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dcor/scier/Giornata chimica 2012/Book Ferrara
XII Giornata di Chimica
dell’Emilia-Romagna
Chimica e Sostenibilità: nel mondo della scuola e dell’industria
Lunedì 17 Dicembre 2012
Università degli Studi di Ferrara
Polo Chimico Bio Medico (Mammut)
SALA ACQUARIO
Comitato Organizzatore
Prof. M. Chiara Pietrogrande, Prof. Vinicio Zanirato
ŽƩ͘ůĞŶĂ^ĂƌƟ͕ŽƩ͘DĂƌĐŽsŝƐĞŶƟŶ
con il contributo di
La SCI ha celebrato nel 2009 il suo primo centenario, poiché è nata il 1 gennaio del 1909, riunendo in
forma federativa la Società Chimica di Milano e la Società Chimica di Roma. Sebbene siano passati più
di cento anni, la Società è attualmente attiva con circa 4000 soci ed è suddivisa in 17 sezioni regionali, 12
divisioni tematiche e 18 gruppi interdisciplinari.
Lo Statuto della SCI, elaborato in Roma il 28 dicembre 1913 e approvato nel 1914 dalle Sezioni, è il
seguente:
Art. 1 – E’ costituita una SOCIETÀ CHIMICA ITALIANA con sede in Roma. Essa ha lo scopo di
promuovere e seguire lo sviluppo della Chimica, delle Scienze affini e delle relative applicazioni,
occupandosi di problemi di indole e di interesse generale, di ricerche sperimentali, insegnamento, ecc., a
mezzo di letture, conferenze, discussioni e di un fecondo scambio di idee fra i soci. A tale intento la
Società terrà riunioni ordinarie e straordinarie.
Art. 2 – La Società Chimica Italiana comprende per ora tre Sezioni: una a Roma, una a Milano, una a
Napoli. Ogni Sezione ha un proprio Consiglio Direttivo e la sua azione si svolgerà con norme che saranno
stabilite nelle singole sedi, mediante propri regolamenti interni, purché in armonia col presente statuto e
regolamento della Società Chimica Italiana
Art. 3 – La Società Chimica Italiana pubblicherà un Bollettino nel quale si renderà conto delle sedute
delle Sezioni, si riporteranno in sunto le comunicazioni fatte dai soci, conferenze ecc.
Art. 4 - Membro della Società Chimica Italiana può essere chiunque si interessi dei progressi della
Chimica. La domanda di ammissione a socio dovrà essere presentata alla Presidenza della Sezione cui si
desidera essere iscritti.
In conformità con i propri fini statutari e seguendo le linee-guida stabilite dagli organi istituzionali, la
Società Chimica Italiana cura la diffusione della cultura chimica e tutela la dignità della chimica nei vari
settori socio-economici del Paese e la professionalità del chimico. A tal fine la Società Chimica Italiana:
(a) stimola, discute e documenta l'attività scientifica e didattica svolta da studiosi italiani e stranieri,
curando l'edizione, direttamente o attraverso accordi con editori, di riviste, libri e manuali. "La Chimica e
l'Industria" è l'organo ufficiale della Società Chimica Italiana; "La Chimica nella Scuola" è dedicata alla
Didattica Chimica. La "Gazzetta Chimica Italiana", "Il Farmaco" ed "Annali di Chimica" sono entrate nel
corpo delle nuove riviste europee, rispettivamente: "European Journal of Organic Chemistry" e "European
Journal of Inorganic Chemistry"; "ChemMedChem"; "ChemSusChem". Inoltre la Società Chimica
Italiana partecipa in co-proprietà con altre Società Chimiche Europee alla gestione di altre riviste.
(b) organizza periodicamente congressi e convegni nonché scuole e altre manifestazioni utili a diffondere
la cultura chimica, e a qualificare la Società Chimica Italiana presso l'opinione pubblica. Organizza
l'Assemblea Generale dei Soci.
(c) esprime il riconoscimento dei meriti di insigni rappresentanti della cultura chimica, assegnando
medaglie e premi secondo appositi regolamenti, utilizzando fondi specifici a bilancio.
La Sezione dell’Emilia Romagna è la seconda come numero di iscritti (circa 450) ed ha avuto un
incremento di 30 nuovi soci nel 2012. Ogni anno organizza la “Giornata della Chimica”, rivolta ai
Dottorandi che frequentano le sedi Universitarie regionali e i “Giochi della Chimica” aperti a tutti gli
studenti delle scuole superiori della regione, con lo scopo di stimolare tra i giovani l'amore per questa
disciplina e di selezionare la squadra italiana per partecipare alle Olimpiadi internazionali della Chimica.
Il consiglio direttivo della sezione Emilia Romagna della SCI per il triennio 2012-2014 è costituito da:
Prof. Claudia Tomasini – Università di Bologna (Presidente)
Prof. Merinella Roberti – Università di Bologna (Vice-Presidente)
Prof. Sonia Melandri – Università di Bologna (Segretario e Tesoriere)
Dr. Mariafrancesca Fochi – Università di Bologna (Responsabile dei Giochi della Chimica)
Prof. Andrea Cornia – Università di Modena e Reggio Emilia
Dr. Erika Ferrari – Università di Modena e Reggio Emilia
Dr. Giorgio Merlante – Delta Engineering Services
Prof. Giovanni Mori – Università di Parma
Prof. Claudio Mucchino – Università di Parma
Dr. Vincenzo Palermo – CNR, Bologna
Prof. Maria Chiara Pietrogrande – Università di Ferrara
Prof. Vinicio Zanirato – Università di Ferrara
Prof. Rossana Zanoli – ITI Corni, Modena
A tutti loro va il mio più sentito ringraziamento per l’entusiasmo e l’impregno profusi nell’organizzazione
di questi eventi.
Desidero inoltre ringraziare gli sponsor che, con il loro contributo, hanno reso possibile l’organizzazione:
Barilla, Basf, Chiesi Farmaceutici, Delta Engineering Services, FABS, Istituto di Ricerche
Esplosivistiche, Ordine dei Chimici di Ferrara, Ordine dei Chimici di Parma, Randi Group, SigmaAldrich.
Auguro a tutti buon lavoro.
Il Presidente della SCI-Sezione Emilia Romagna
Prof. Claudia Tomasini
Programma
Ore 09:00-09.45
Registrazione, allestimento poster e caffè di benvenuto
Ore 09:45-10:00
Apertura dei lavori:
Saluto del Magnifico Rettore, Prof. Pasquale Nappi
Prof Gian PieroPollini , Direttore Istituto universitario di Studi superiori
Prof. Severo Salvadori, Direttore Dip. Scienze Chimiche e Farmaceutiche
Prof. Claudia Tomasini, Presidente SCI-Sezione Emilia Romagna
I Sessione: Comunicazioni dei Dottorandi
Ore 10:00-11:30
Comunicazioni orali
Chairman: Dott. Erika Ferrari, Università di Modena e Reggio Emilia
10.00-10.20 Dr. Salvatore Pacifico, Università di Ferrara: “Reactivity of dialkyl and diaryl α-diketones
with N-heterocyclic carbenes”
10.20-10.40 Dr. Tommaso Avellini, Università di Bologna: “Photoinduced memory effect in a redox
controllable bistable mechanical molecular switch”
10.40-11.00 Dr. Lucia Bertacchini, Università di Modena e Reggio Emilia: “Geographical traceability
studies for the oenological chain valorisation”
11.00-11.20 Dr. Alessandro Bedini, Università di Parma: “Rapid and simultaneous analysis of xanthines
and polyphenols as bitter taste markers in bakery products by FT-NIR spectroscopy ”
Ore 11:30-13:00
Comunicazioni flash
Dr. Davide Rosestolato, Università di Ferrara: “Investigation on the active chlorine production from
dilute chloride solutions and electrochemical reactivity of the side-products”
Dr. Emanuela Ruggiero, Università di Ferrara: “7-Oxo-[1,4]oxazino[2,3,4-ij]quinoline-6-carboxamides
as Selective CB2 Cannabinoid Receptor Ligands: Structural Investigation around a Novel Class of Full
Agonists ”
Dr. Camilla Delpivo, Università di Bologna: “Nanoparticle Surface Engineering: Challenging Properties
Of Silica Coatings”
Dr. Gian Paolo Di Martino, Università di Bologna: “An Automated Docking Protocol for hERG Channel
Blockers”
Dr. Qian Gou, Università di Bologna: “Fourier Transform Microwave Spectra of Several Isotopologues
of Isoflurane-Water Complex”
Dr. Vittorio Sorella, Università di Bologna: “Dried Blood Spot and mass spectrometry: an analytical tool
to certify Cannabis actual state of intoxication”
Dr. Andrew Anighoro, Università di Modena e Reggio Emilia: “Targeting the Hsp90 interactome using in
silico polypharmacology approaches”
Dr. Davide Presti, Università di Modena e Reggio Emilia: “On the ability of periodic dispersioncorrected DFT calculations to predict molecular crystal polymorphism in para-diiodobenzene”
Dr. Fabio Angiuli, Università di Parma: “Luminescence properties and emission dynamics of YPO4
activated with Tb3+ and Bi3+”
Dr. Giulia Cantoni, Università di Parma: “Inclusion propensity of new wheel-and-axle complexes based
on Ru(II) half-sandwich units”
Ore 13:00-14:30
Buffet lunch - Sessione poster
II Sessione: Chimica e Sostenibilità: nel mondo della scuola e dell’industria
Chairman: Prof Gian PieroPollini, Università di Ferrara
Ore 14:45-15:00
Ore 15:00-15:15
Ore 15:15 15:30
Ore 15:30-15:45
Ore 15:45-16:00
Ore 16:00-16:30
Responsible Care
(Dott Cosimo Franco - Endura S.p.A. Commissione Direttiva Federchimica)
Esperienza di Responsible Care
(Dott. L. Dal Pozzo - BASF Italia Srl).
Esperienza di Responsible Care
(Ing. G. Mei - Basell Poliolefine Italia Srl)
Percorsi formativi professionali e universitari
(Dott. G. Merlante – Ordine dei Chimici Provincia di Ferrara)
Educazione alla sostenibilità: Il progetto Unife-Sostenibile
(Prof. Francesco Dondi - Unife)
Premiazione dottorandi e classi delle Scuole Superiori
Chiusura dei lavori
Prof. Claudia Tomasini, Presidente SCI-Sezione Emilia Romagna
ABSTRACTS DELLE COMUNICAZIONI ORALI
OC 1
Dr. Salvatore Pacifico
pag. 2
OC 2
Dr. Tommaso Avellini
pag. 3
OC 3
Dr. Lucia Bertacchini
pag. 4
OC 4
Dr. Alessandro Bedini
pag. 5
OC 1
Reactivity of dialkyl and diaryl α-diketones with N-heterocyclic carbenes
Salvatore Pacifico, Giancarlo Fantin, Marco Fogagnolo, Pier Paolo Giovannini, Alessandro Massi, and
Olga Bortolini
Dipartiment of Chemistry and Pharmaceutical Sciences University of Ferrara, Ferrara, Italy
[email protected]
In recent years, N-heterocyclic carbenes (NHCs) have attracted considerable interest due to their unique
features, which allow them to be used as ligands for organometallic catalysis, reagents in the synthesis of
heterocycles, and efficient organocatalysts in umpolung transformations. In the latter sub-area of research
many efforts have been devoted to the realization of highly stereoselective versions of the classical
benzoin and Stetter reactions through optimal pre-catalyst design, to the discovery of new
transformations, and to the umpolung of electrophiles alternative to aldehydes and pyruvates, mainly
acylsilanes and Michael acceptors. In this regard, our group has recently demonstrated the capability of
linear and cyclic dialkyl α-diketones to undergo polarity reversal under thiazolium carbene catalysis in
benzoin-type (1) and Stetter reactions (2), and thus act as a novel class of acyl anion precursors.
Contrarily, it has been observed that diaryl α-diketones do not undergo polarity reversal in the presence of
(benzo)thiazolium carbenes but are engaged in a novel multicomponent reaction with water to efficiently
give medicinally relevant 1,4-thiazin-3-one heterocycles (3). The umpolung reactivity of diaryl 1,2diones, however, can be effectively triggered by different NHCs. An overview of this research is herein
presented.
R1
O
O
O
Me
HO
OEt
Me
OEt
benzoin-type
Me
Ph
O
Ph
O
Ph
Ph
R2
Ph
S
R3
multicomponent
reaction (MCR)
O
R
R
O
N
+ BzOH
H 2O
O
Me
O
+ NHCs
O
O
H
R = Me, Ph
benzoin-type
Stetter
O
Ar
Ph
* Ar
OBz
(1) O. Bortolini, G. Fantin, M. Fogagnolo, P. P. Giovannini, V. Venturi, S. Pacifico, A. Massi, Tetrahedron 2011, 76, 81108115.
(2) O. Bortolini, G. Fantin, M. Fogagnolo, P. P. Giovannini, A. Massi, S. Pacifico, Org. Biomol. Chem. 2011, 9, 8437-8444.
(3) V. Bertolasi, O. Bortolini, A. Donvito, G. Fantin, M. Fogagnolo, P. P. Giovannini, A. Massi, S. Pacifico, Org. Biomol.
Chem. 2012, DOI:10.1039/C2OB25928A.
2
OC 2
Photoinduced memory effect in a redox controllable bistable mechanical molecular
switch
1
Tommaso Avellini, 2Hao Li, 2,3Dr. Ali Coskun, 2Gokhan Barin, 4Dr. Ali Trabolsi, 2Ashish N.
Basuray, 2Dr. Sanjeev K. Dey, 1Prof. Alberto Credi, 1Dr. Serena Silvi, 2,3Prof. J. Fraser Stoddart,
1
Prof. Margherita Venturi
1
2
'LSDUWLPHQWRGL&KLPLFD³*&LDPLFLDQ´8QLYHUVLWjGL%RORJQD9LD6HOPL%RORJQD,WDO\
Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208 (USA)
3
NanoCentury KAIST Institute and Graduate School of EEWS (WCU), Korea Advanced Institute of
Science and Technology (KAIST), 373-1 Guseong Dong, Yuseong Gu, Daejeon 305-701 (Korea)
4
Center of Science and Engineering, New York University Abu Dhabi, Al Nasr Street, Abu Dhabi
(United Arab Emirates)
[email protected]
A controllable molecular shuttle is a rotaxane that bears in the thread-like molecule (dumbbell) two or
more units, whose affinity for the macrocycle can be tuned using external stimuli(1,2). As result, the
macrocycle can shuttle along the dumbbell.
In this work we present a study on two bistable molecular shuttles composed of cyclobis(paraquat-pphenylene) (CBPQT, the ring) and a dumbbell-shaped molecule containing three functional unit: 1) a
tetrathiafulvalene (TTF), 2) a dioxynaphtalene moiety (DNP) and 3) an azobenzene unit (AZO) (3). The
rotaxanes have different substituents on AZO unit. TMeABrot has methyl groups while TFABrot has
fluorine groups. TTF and DNP are two electron-donor units, that interact with the electron-acceptor
CBPQT. AZO is a photocromic molecule that can be reversibly photoisomerized from its stable trans
form to the metastable cis form. Initially the CBPQT is positioned on the TTF unit. After oxidation of the
TTF unit, the CBPQT shuttles from TTF to the DNP unit across the trans-AZO. Upon UV irradiation, the
AZO unit isomerizes from trans to cis. Reduction of the TTF+ unit restores the initial situation under the
electronic viewpoint but not for the conformational aspect: the rotaxane is locked in a metastable state
where the CBPQT is forced to interact with DNP. The initial conformation is restored upon the thermal or
photochemical trans to cis conversion of the AZO unit. Here we report the photochemical and
spectroscopic characterization of the two rotaxane and we demonstrate the possibility to lock more than
50% of the TMeABrot molecule in the metastable state. This rotaxane is an example of flash memory
where the written information is not erased after the removal of the writing stimulus(4). TFABrot cannot
be locked in a metastable state, according to the smaller steric hindrance of the fluorine substituent on the
AZO unit.
N
O
O
O
O
O
N
S
S
S
S
N
O
O
O
O
N
NN
O
O
O
O
O
N
NN
O
N
N
O
O
O
O
O
O
O
O
N
NN
O O
O
O
O O
O
O
N
4PF6-
a)
N
N
F
O
O
O
O
O
N
b)
O
O
N
NN
S
S
S
S
F
N
N
F
F
N
4PF6-
Figure 1: a) TMeABrot; b) TFABrot
(1) Balzani, V.; Credi, A.; Venturi M. Molecular Devices and Machines ± Concepts and Perspectives for the Nano World,
Wiley-VCH, Weinheim, 2008.
(2) Balzani, V.; Clemente-León, M.; Credi, A.; Ferrer, B.; Venturi M.; Flood, A. H.; Stoddart, J. F. Proc. Natl. Acad. Sci. USA.
2006, 103, 1178±1183.
(3) Coskun, A.; Friedman, D. C.; Kaushik Patel, H. L.; Khatib H. A.; Stoddart, J. F. J. Am. Chem. Soc. 2009, 131, 2493±2495
(4) Avellini T.; Li H.; Coskun A.; Barin G; Trabolsi A.; Basuray A.N.; Dey S.K.; Credi A.; Silvi S.; Stoddart J.F.; Venturi M.;
Angew. Chem. Int. Ed., 2012, 51, 1611-1615.
3
OC 3
Geographical traceability studies for the oenological chain valorisation
Lucia Bertacchini, Carlo Baschieri, Marina Cocchi, Caterina Durante, Andrea Marchetti, Simona
Sighinolfi, Michele Silvestri.
Department of Chemical and Geological Sciences, University of Modena and Reggio Emilia,
via Campi 183, 41125 Modena (Italy).
[email protected]
Nowadays, food quality, traceability and tracking systems, are frequently mentioned and they should play
a primary role in the society mainly due to the several episodes that threat the authenticity and safety of
foodstuffs. In oenological field, the quality of wine is mainly related with the history of the product, its
geographical origin, the used raw materials, etc. To assess the link between the territory and the food, the
producer wants to convey these information since they represent a peculiar added value, useful for the
enhancement of the product itself. Hence, the geographical traceability of a food might be a powerful tool
to support consumers confidence and could represent a special component for those products that already
have a high reputation (1).
The present work is part of a research project focused on the development of geographical traceability
models of wines, in particular Lambrusco and TrentoDOC wines, which are among the main typical
products of the Modena and Trento districts.
The proposed approach is based on the synergistic use of both advanced analytical instrumentation, to
obtain data characterized by high accuracy and precision, and multivariate data analysis tools for an
optimized, efficient and low time consuming data evaluation. Main topics of this approach are: i)
planning of a systematic and representative sampling (both for soils and food), ii) optimization of the
analytical procedures for the determination of traceability indicators, iii) investigation of the peculiarities
and variability of the indicators and iv) development of robust traceability models.
Among the different analytical indicators used for traceability studies, the 87Sr/86Sr isotopic ratio proved
to give excellent results for different types of food matrices and in particular for oenological products (2,
3). The Sr isotopic ratio varies according to the age of the rocks, the initial 87Rb/87Sr value and the elapsed
time. Besides, the Sr is actively involved in the metabolism of bio-organisms. Therefore, with the aim of
using this isotopic ratio as geographical marker in traceability studies, it is of utmost importance to obtain
an a priori knowledge of the investigated systems.
First of all, a preliminary screening of the soils was performed by means of X-ray diffraction of powdered
samples and chemometrics techniques, in order to evaluate in a simple and relatively fast way the inter
and intra site variability of soil, considering also the influence of sampling depth and period, and thus to
obtain indications about the soil sampling procedure (e.g. the depth of sampling, the number and the
location of samples within the same farm, the period of the sampling).
After that, the 87Sr/86Sr isotopic ratio was determined by means of Multi Collector ICP Mass
Spectrometry in different matrices of the oenological chain (soil – branch – grape juice) to monitor the
variability of the indicator in the soil or during the grapevine uptake. The results highlighted a good
match between the isotopic values monitored in the soil fractions mimicking the bio-available part and
their respective grape juices for almost all the investigated geographical areas. The correlation with food
matrices satisfyingly improves when the isotopic values of vine branches are considered.
(1) Van Rijswjik, W.; Frewer, L.J.; Menozzi, D. & Faioli, G. Food Qual. Prefer. 2008, 19, 452-464.
(2) Horn, P., H˚lzl, S., Todt, W., Matthies, D. Isotopes Environ. Health Stud. 1998, 34,31-42.
(3) Brunner M.; Katona R.; Stefànka Z. & Prohaska T. Eur. Food Res. Technol. 2010. 231, 623- 634.
4
OC 4
Rapid and simultaneous analysis of xanthines and polyphenols as bitter taste
markers in bakery products by FTͲNIR spectroscopy
1
Alessandro Bedini, 2Valentina Zanolli ,3Sandro Zanardi, 3Ugo Bersellini, 1Enrico Dalcanale, 3Michele Suman.
1
Dipartimento di Chimica, Università di Parma, (Parco Area delle Scienze 17A,43124 Parma, Italy e-mail
[email protected] , [email protected])
2
Büchi Italia Srl (Strada 4, 20090 Milano Fiori Milan, Italy).
3
Barilla SpA (Food Research Labs, via Mantova 166, 43122 Parma, Italy, e-mail : [email protected]).
Measured Xanthines
Cereal Cookie
Theoretical Xanthines
Lemon Cookie
Coffee Cookie
Honey Cookie
Cream Cookie
Chocolate and cream Cookie 2
Chocolate and cream Cookie
Nuts Cookie
Chocolate Cookie 3
Chocolate Cookie 2
Chocolate Cookie
0.0
500.0
1000.0
1500.0
mg kg-1
The understanding of the molecular origin and the transduction process of bitter taste on the human tongue represents a great
challenge for scientists because of the contemporaneous involvement of several receptors and many different
targetͲcompounds. The food industry is continuously looking for rapid methods useful to standardize different control
parameters and has a direct interest into bitterͲtasting substances, either for the identification of negative offͲflavors or for the
monitoring of a desired organoleptic quality. The exploitation of dedicated panel tests for sensory purposes is useful but it
suffers of limitations related to subjectivity, reproducibility and number of analysis per day (Profile Attribute Analysis). On the
contrary, sophisticated analytical approaches, such as LCͲMS, need trained personnel and are often too expensive and/or time
consuming. The target of the present research work is therefore the development of a rapid technique based on a Fourier
TransformͲ Near InfraRed Spectroscopy (FTͲNIR) platform potentially able to detect taste molecular markers in bakery
commodities, mainly xanthines (caffeine, theobromine, theophylline), polyphenols (catechins, epicatechins) and sugars
(sucrose) which are considered responsible for the overall bitterͲtaste of coffee\cocoa\chocolate based products. Sugars affect
the bitter taste suppressing it and they are usually present in large quantities inside bakery commodities like biscuits
(percentage point on a weight basis). In particular, eleven types of commercial biscuits made with different amounts of various
ingredients like cocoa beans, chocolate, nuts, cream, etc., were here considered. Relevant concentrations of xanthines and
polyphenols were, firstly, checked using a confirmatory LCͲESI\MSͲMS procedure and then used for the calibration of the
FTͲNIR spectrophotometer by using partial least squares (PLS) regression. Values of the standard errors of prediction (lower
than 10% either for polyphenols, xanthines or sugars) were comparable to the values of the standard errors of crossͲvalidation.
Coefficients of determination indicated a good predictive power in the calibration model (R 2 xanthines = 0.97, R2 polyphenols
= 0.96, R2 sugars= 0.93) and a similar satisfying discriminating power among different contents in the validation models (R 2
xanthines = 0.96, R2 polyphenols = 0.96, R2 sugars= 0.93). A testing phase of the generated model was executed by a
comparison of further LCͲMS and sensory panel data with FTNIR responses recorded on unknown biscuits: concentration
differences between found and predicted levels were generally below 5% and the best predictability was achievable in
chocolateͲbased biscuits. A Design of Experiment approach was realized in order to investigate on a correlation between the
Profile Attribute Analysis and the two developed analytical techniques (LC-MS and FT-NIR). This approach reveals that the
selected bitter taste molecular markers are between the major contributor to the overall bitter sensation and that their detection
with FT-NIR can be effectively used for the taste prediction.
In conclusion, this methodology is able to work directly on solid products (1), and can be conceived as applicable for a routine
control of a standardized bitter taste quality in a real industrial production field.
1 -Bedini A., Zanolli V., Zanardi S., Bersellini U., Dalcanale E., Suman M., Food Analytical Methods, (2012),
DOI : 10.1007/s12161-012-9405-7
5
ABSTRACTS DELLE COMUNICAZIONI FLASH
FC 1
Dr. Davide Rosestolato
pag. 7
FC 2
Dr. Emanuela Ruggiero
pag. 8
FC 3
Dr. Camilla Delpivo
pag. 9
FC 4
Dr. Gian Paolo Di Martino
pag. 10
FC 5
Dr. Qian Gou
pag. 11
FC 6
Dr. Vittorio Sorella
pag. 12
FC 7
Dr. Andrew Anighoro
pag. 13
FC 8
Dr. Davide Presti
pag. 14
FC 9
Dr. Fabio Angiuli
pag. 15
FC 10
Dr. Giulia Cantoni
pag. 16
FC 1
Investigation on the active chlorine production from dilute chloride solutions and
electrochemical reactivity of the side-products
1
1
Stefano Neodo, 2Davide Rosestolato, 2Sergio Ferro, 2Martina Donatoni, 2Achille De Battisti
nCATS, Engineering Sciences, University of Southampton, Highfield, Southampton, Hampshire, SO17
1BJ, UK.
2
Università di Ferrara, Dipartimento di Scienze Chimiche e Farmaceutiche,
via L. Borsari 46, 44121 Ferrara, Italy
[email protected]
The electrolytic process of dilute aqueous chloride solutions (0.07 M) was investigated at Ti/RuO2.2SnO2
and Ti/Pt electrodes, at different values of current density (250, 750 and 1500 A m-2), temperature (10, 25
and 65 °C) and electrolysis time (0 – 180 minutes).
The time evolution of chlorine-related species (i.e. active chlorine, chlorite, chlorine dioxide, chlorate and
perchlorate), as well as their faradic efficiency, was investigated to understand whether their formation
and consumption was either chemical or electrochemical.
Different current efficiency profiles were generally observed for the two explored electrode materials,
when the applied current density and the temperature were varied in the above reported experimental
intervals. At the Ti/RuO2.2SnO2 (especially at the lowest current density), similar current efficiencies for
the synthesis of active chlorine and chlorate were estimated. On the contrary, rather low current
efficiencies for active chlorine and high current efficiencies for chlorate and perchlorate were measured at
the Ti/Pt electrode.
The concentration trends of chlorate and perchlorate indicated that the electrochemical route was
responsible for their presence in the bulk solution, instead of a chemical path. This insight was
corroborated by the measure of anodic potentials: high values for the anode potential were indeed related
to high current efficiencies for chlorate and perchlorate.
The low concentration levels (and thus low current efficiencies) assessed for chlorite and chlorine dioxide
throughout the tests were not useful for discriminating between a chemical and an electrochemical
depletion processes; however, further potentiodynamic tests suggested that chlorites are highly reactive
towards both anodic and cathodic surfaces, thus suggesting that the electrochemical path of depletion
could prevail over the chemical one. Conversely, due to a solution pH quite unfavourable to the stability
of chlorine dioxide, its low concentration level was justified by a chemical depletion route (1).
(1) S. Neodo, D. Rosestolato, S. Ferro, A. De Battisti, Electrochimica Acta 2012, 80, 282-291
7
FC 2
7-Oxo-[1,4]oxazino[2,3,4-ij]quinoline-6-carboxamides as Selective CB2 Cannabinoid
Receptor Ligands: Structural Investigation around a Novel Class of Full Agonists
1
Pier Giovanni Baraldi, 1Giulia Saponaro, 1Delia Preti, 1Stefania Baraldi, 1Emanuela Ruggiero, 2Pier
Andrea Borea, 1Mojgan Aghazadeh Tabrizi
1
Dipartimento di Scienze Farmaceutiche, Università di Ferrara, Via Fossato di Mortara 17-19, 44121
Ferarra
2
Sezione di Farmacologia, Dipartimento di Medicina Clinica e Sperimentale, Università di Ferrara, Via
Fossato di Mortara 17-19, 44121 Ferarra
[email protected]
Cannabinoid receptor agonists have gained attention as potential therapeutic targets of inflammatory and
neuropathic pain(1). Here, we report the identification and optimization of a series of 7-oxo[1,4]oxazino[2,3,4-ij]quinoline-6-carboxamide derivatives as a novel chemotype of selective cannabinoid
CB2 receptor agonists. Structural modifications led to the identification of several compounds as potent
and selective cannabinoid receptor agonists(2). The effect of a chiral center on the biological activity was
also investigated, and it was found that the (R)-enantiomers exhibited greater affinity at the CB2 receptor
than the (S)-enantiomers. In 3,5-cyclic adenosine monophosphate assays, the novel series behaved as
agonist, exhibiting functional activity at the human CB2 receptor.
O
O
O
O
O
N
H
N
H
N
O
N
N
H
N
N
H
O
hKi CB2 = 0.81 nM,
hKi CB1 = 310 nM
O
O
hKi CB2 = 8.12 nM,
hKi CB1 >1000 nM
hKi CB2 = 9.24 nM,
hKi CB1 >1000 nM
(1) Jhavery, M.D.; Richardson, D.; Chapman, V. Br. J. Pharmacol. 2007, 152, 624-632.
(2) Baraldi, P.G.; Saponaro, G.; Moorman A.R.; Romagnoli R.; Preti D.; Baraldi, S.; Ruggiero, E.; Varani, K.; Targa, M.;
Vincenzi, F.; Borea, P.A.; Aghazadeh Tabrizi, M. J. Med. Chem., 2012, 55 (14), pp 6608±6623
8
FC 3
Nanoparticle Surface Engineering: Challenging Properties Of Silica Coatings
1
Anna Luisa Costa, 1Magda Blosi, 1Camilla Delpivo, 1Davide Gardini, 1, 2Stefania Albonetti, 1, 2Angelo
Vaccari, 1Michele Dondi
1
2
CNR-ISTEC, Faenza (RA)
Dip. di Chimica Industriale e dei Materiali, Bologna
[email protected]
In the last years, nanoparticles (NPs) surface modification, through the realization of organic or inorganic
coatings, are receiving growing interest since allows to create new materials (hybrids, composites, coreshell structures) with engineered properties (1). In particular, among inorganic compounds that can be
used for coatings, those based on silica (SiO2) have attracted high attention due to their hydrophilic
properties, biocompatibility, thermal inertness, high chemical stability and great dispersibility even in
aqueous media (2). The goal of the present work is the production and characterization of SiO2-coatings
on titanium dioxide (TiO2) and silver (Ag) NPs dispersed in aqueous solutions (commercial nanosols,
Colorobbia Italia Spa) with the aim to manage the potential risk that arises from such nanoparticles within
an occupational exposure scenario (activities performed on behalf of EU-FP7 - Collaborative Project
SANOWORK).
Two different approaches were followed as schematized
in Figure 1: i) a colloidal approach, based on principles
of heterocoagulation, in which opposite charged NPs of
TiO2 or Ag and SiO2 are forced to coagulate with a
hierarchical structure imposed by their relative size and
weight ratio; ii) a chemical approach, where a silica
shell was formed on TiO2 or Ag NPs, that acts as
nucleation seeds, from silica precursor solutions (TEOS,
Stöber process). Among these approaches, we focused on
the colloidal one because seems to be the most practical
and cost-effective strategy for silica coating of
Figure 1 Silica engineering of nanoparticles
nanoparticles dispersed in water solution at industrial
level. In order to increase the adhesion of silica on TiO2 and Ag surfaces, heterocoagulated sols
underwent to spray-drying and re-dispersion steps in order to improve heterocoagulation and provide a
general tool for powder drying and re-dispersing, preserving as much as possible the characteristics of
starting nanosol. The results of physicochemical characterization such as Z potential, electrical
conductivity, particle size distribution, specific surface area, micro-Raman, UV-Vis, FT-IR and XPS
patterns, SEM/TEM morphology and EDX analysis allowed to optimize the coating process and to assess
the features of silica modified samples. The more promising samples were sent to SANOWORK partners
for toxicological characterization.
References
(1) SPEARLING, R. A.; PARAK, W. J.; Phil. Trans. R. Soc. 2010, 368, 1333-1383,
(2) GUERRERO-MARTINEZ, A.; PEREZ-JUSTE J.; LIZ-MARZAN, LUIS M. Adv. Mat. 2010, 22, 1182±1195,
9
FC 4
An Automated Docking Protocol for hERG Channel Blockers
1
1
G.P. Di Martino, 1M. Masetti, 1L. Ceccarini, 1,2A. Cavalli,1M. Recanatini
Department of Pharmacy and Biotechnology, University of Bologna, Via Belmeloro 6, I-40126 Bologna,
Italy.
2
Department of Drug Discovery and Development, Istituto Italiano di Tecnologia, Via Morego 30, I16163 Genova, Italy.
[email protected]
The voltage-gated hERG K+ channel modulates the rapid delayed rectifier current (IKr) in human heart,
playing a critical role in cardiac action potential repolarization. Several drugs bind to the channel inner
cavity causing the blockade of ion conduction, and thus increasing the risk of potentially lethal
arrhythmias (drug induced LQT syndrome).(1) Despite of the seriousness of this side effect, a detailed
description of the physico-chemical features at the basis of the block is still partially lacking. In this
context, the use of protein-ligand docking techniques, which is in principle a valuable tool to rationalize
structure-activity relationships, has been strongly hampered either by the absence of a crystallographic
structure of the channel, or by difficulties related to the peculiar nature of the drug blockers binding
site.(2) In particular, the role played by the intrinsic symmetry of the channel and by the entropic
contribution to the binding, which is expected to be relevant for an essentially non-polar binding site, are
aspects usually neglected in current docking protocols. To overcome these issues, we designed a strategy
that explicitly takes in account the conformations of the channel, their possible intrinsic symmetry, and
the role played by the configurational entropy of ligands. By applying our protocol to a series of
congeneric Sertindole derivatives,(3) we obtained a small set of putative structure-based models able to
satisfactorily explain structure-activity relationships for the employed set of blockers. For each of these
models, it turned out to be possible to rationalize the blocking activity in terms of specific interactions
between the ligands and the channel. Additionally, we show that the performance of structure-based
models relying on a multiple receptor conformation description statistically increases when a small subset
of protein conformations capturing the relevant structural features for binding is used.
(1) Sanguinetti, M.C.; Jiang, C.G.; Curran, M.E.; Keating, M.T. Cell 1995, 81, 299-307.
(2) Recanatini, M.; Cavalli, A.; Masetti, M. ChemMedChem 2008, 4, 523-535.
(3) Pearlstein, R.A.; Vaz, R.J.; Kang J.; Chen, X.L.; Preobrazhenskaya, M.; Shchekotikhin, A.E.; Korolev, A.M.; Lysenkova,
L.N.; Miroshnikova, O.V.; Henrix, J.; Rampe, D. Bioorg. Chem. Med. Lett., 2003, 13, 1829-1835.
10
FC 5
Fourier Transform Microwave Spectra of Several Isotopologues of
Isoflurane-Water Complex
1
Qian Gou, 1Gang Feng, 1Luca Evangelisti, 2Montserrat Vallejo, 2Alberto Lesarri, 1Walther Caminati
1
'LSDUWLPHQWRGL&KLPLFD³*&LDPLFLDQ´GHOO¶8QLYHUVLWj9LD6HOPi 2, I-40126 Bologna, Italy
Departamento de Química Física y Química Inorganica, Facultad de Ciencias, Universidad de
Valladolid, E-47011 Valladolid, Spain
[email protected]
2
The rotational spectra of the 1:1 complex between the inhalational anesthetic isoflurane (1-chloro-2,2,2trifluoroethyl difluoromethyl ether, C3H2ClF5O) and water have been recorded and assigned using Fourier
transform microwave technique, associated with ab initio calculations. Only one conformer of this
complex was identified which adopts the global minimum of isolated isoflurane (1) bonding with water
through C-H«O and O-H«F-C weak hydrogen bonds as shown in Figure 1. Each transition displays as
hyperfine structure (see Figure 1) because of the nuclear quadrupole moment of the 35Cl (or 37Cl) nucleus.
Besides that of the normal species C3H235ClF5O-H2O, the rotational spectrum of C3H237ClF5O-H2O
isotopologue was searched and assigned, in natural abundance. The rotational spectra of three more
isotopologues C3H2ClF5O-H218O, C3H2ClF5O-DOH, C3H2ClF5O-D2O were also measured. Within the
pseoudo-diatomic model approximation, the dissociation energy has been estimated.
Figure 1. Recorded 707ĸ606 transition of the observed conformer of C3H2ClF5O±H2O showing the
35
Cl hyperfine
structure. Each component line exhibits the Doppler doubling.
Reference:
(1) Lesarri, A.; Vega-Toribio, A.; Suenram, R.D.; Brugh, D.J.; Nori-SHargh, D.; Boggs, J.E.; Grabow, J.-U.; Phys. Chem.
Chem. Phys. 2011, 13, 6610-6618.
11
FC 6
Dried Blood Spot and mass spectrometry: an analytical tool
to certify Cannabis actual state of intoxication
1
Vittorio Sorella, 1Laura Mercolini, 1Roberto Mandrioli, 2Giovanni Serpelloni, 1Maria Augusta Raggi
1
Laboratory of Pharmaco-Toxicological Analysis, Department of Pharmacy and BioTechnology,
Alma Mater Studiorum - University of Bologna, Via Belmeloro 6, 40126 Bologna, Italy
2
Department for Antidrug Policies ± Ministry for International Cooperation and Integration,
Via Po 16/A, 00198 Rome, Italy
[email protected]
Driving under the influence of Cannabis (DUI) has become a growing concern. Studies investigating the
impact of DUI on traffic safety have shown evidence that, during the acute period of Cannabis
intoxication, Cannabis diminishes driving faculties greatly increasing the risk of car accidents (1).
However, the actual state of Cannabis intoxication is not easily assessed, particularly in specific contexts
such as roadside testing. Until now, the most reliable biological matrix for this purpose in represented by
blood but its sampling is invasive and requires a sanitary environment and subsequent treatments or
storage precautions, such as centrifugation, refrigeration or freezing. The time lapse between the
individuation of a possible intoxication and the blood sampling is very important, since a long delay can
mean that, in the meantime, the drug blood levels physiologically decrease under the cut-off value. To
overcome this disadvantage, Dried Blood Spots (DBSs) can be a valid alternative to the normal blood
sampling by venipuncture. In fact this innovative biological matrix can be obtained after a fast and easy
sampling, does not need any particular storage nor transportation precaution and is stable over time.
To strictly monitor Cannabis consumption, an original LC-MS/MS method has been developed for the
analysis of Cannabinoids in DBSs (2). Attention has been paid to the determination of ǻ9tetrahydrocannabinol (or THC, Figure 1a), the main psychoactive compound whose presence in blood can
be taken as a marker of recent exposure, and its two main metabolites 11-hydroxy-ǻ9tetrahydrocannabinol (THC-OH, Figure 1b) and 11-nor-9-carboxy-ǻ9-tetrahydrocannabinol (THCCOOH, Figure 1c).
CH3
CH 2OH
OH
COOH
OH
H
OH
H
H
H
O
H3C (CH 2)4
CH3
CH3
H
O
H3C (CH 2)4
b
a
THC
CH3
CH3
THC-OH
H
H3C (CH 2)4
O
CH3
CH3
c
THC-COOH
Figure 1
In particular the intermediate hydroxylated metabolite (THC-OH) is pharmacologically active and, at the
same time, it is a marker of recent Cannabis intake, since it appears in blood about 13 minutes after
consumption and has a relatively short half-life. The carboxylated metabolite (THC-COOH) is not
psychoactive and has a very long half-life up to one month for chronic users. For this reason the presence
of this latter compound alone in blood cannot be taken as a marker of recent exposure. Is evident,
therefore, that the simultaneous monitoring of all the three analytes is necessary to outline
pharmacokinetic and toxicokinetic state of abusers and contribute to the assessment of psychophysical
state, distinguishing between acute or former consumption. The analytical method developed has been
fully validated and applied to real DBS samples from Cannabis abusers with satisfactory results, thus
confirming the methodology suitability for roadside testings.
(1) Richer, I.; Bergeron J. Accid. Anal. Prev. 2009, 41, 299±307
(2) Mercolini, L.; Mandrioli, R.; Sorella, V.; Somaini, L.; Giocondi, D.; Serpelloni, G.; Raggi M.A. J. Chromatogr. A. 2012,
in press
12
FC 7
Targeting the Hsp90 interactome using in silico polypharmacology approaches
1
Andrew Anighoro, 2Dagmar Stumpfe, 2Jürgen Bajorath, 1Giulio Rastelli.
1
Dipartimento di Scienze della Vita, Università di Modena e Reggio Emilia, Via Campi 183, 41125
Modena, Italy.
2
Department of Life Science Informatics, B-IT, LIMES Program Unit Chemical Biology and Medicinal
Chemistry, Rheinische Friedrich-Wilhelms-Universität, Dahlmannstr. 2, 53113, Bonn, Germany.
[email protected]
Heat shock response is often activated in cancer cells, contributing to both initiation and maintenance of
the transformed phenotype. Hsp90 is an important component of this process, acting as a molecular
chaperone affecting stability and activation of more than 200 client proteins through ATP hydrolysis
cycles. Proteins interacting with Hsp90 (Hsp90 interactome) are often involved in signaling processes,
such as transcription factors and kinases.
The pivotal role played by Hsp90 in cancer has driven huge efforts in drug discovery aimed at the design
of inhibitors able to interact with this protein (1,2). The most important chemical classes of Hsp90
inhibitors include ansamycins, resorcinol derivatives, purines, imidazopyridines, oxazoles as well as
novel chemotypes. Fourteen drug candidates targeting Hsp90 are now undergoing clinical trials.
Recently, the paradigm of trying to design drugs acting on a single target has evolved in the concept of
polypharmacology, which aims at developing therapeutic agents that interact simultaneously with
multiple targets. One of the key questions concerning this concept is related to which combinations of
targets should be more suited for a polypharmacology approach given a particular disease.
Hsp90 is a key node in many biological networks and interacts with a huge number of client proteins and
co-chaperones (3). Therefore, this target appears highly relevant for polypharmacology approaches,
because a huge number of proteins depend on Hsp90 to elicit their biological activity. Notwithstanding,
the possibility to exploit polypharmacology approaches in Hsp90 is still largely unexplored.
We present a computational polypharmacology approach consisting of molecular database information
analysis and a combined ligand-based/structure-based virtual screening aimed at identifying suitable
target combinations and potentially active compounds for multi-target inhibitor design within the Hsp90
interactome.
(1) Trepel, J.; Mollapour, M.; Giaccone, G.; and Neckers, L. Nature Reviews Cancer 2010, 10, 537-549.
(2) Sgobba, M.; Rastelli, G. ChemMedChem 2009, 4: 1399–1409.
(3) Echeverría P. C., Bernthaler A., Dupuis P., Mayer B., and Picard D. PLoS ONE 2011, 6(10):e26044.
13
FC 8
On the ability of periodic dispersion-corrected DFT calculations to predict
molecular crystal polymorphism in para-diiodobenzene
Alfonso Pedone, Davide Presti and Maria Cristina Menziani
Dipartimento di Scienze Chimiche e Geologiche, Università di Modena e Reggio Emilia, Via G. Campi
183, 41125 Modena, Italy
[email protected]
Periodic Density Functional Theory (DFT) calculations employing the PBE, PBE0 and B3LYP
functionals coupled with different dispersion correction schemes (-D and -TS) have been applied to paradiiodobenzene (p-DIB) molecular crystal in order to determine how they perform in reproducing the
energetic (Fig. 1) and crystal geometry (Fig. 2) of its two well known polymorphs.
Our results (1) demonstrate that, when properly corrected, DFT calculations successfully predict the
relative stability of the α and β phases at zero temperature, in good agreement with Diffusion MonteCarlo (DMC) calculations (2).
Among the two dispersion corrections employed, the recently proposed Tkatchenko and Scheffler (TS)
scheme (3) performs much better than the original scheme (D) proposed by Grimme (4).
This is imputable to the accurate nonempirical method used to obtain the dispersion coefficients in the
former approach. These coefficients, in fact, can vary considerably depending on the chemical
environment in which an atom is embedded, and the original parameterization proposed by Grimme is not
able to capture such differences.
Our work has demonstrated that the PBE-TS functional can be safely used to predict the relative
stabilities and structural packing of organic molecular crystals with a relatively low computational cost
with respect to more sophisticated quantum-mechanical methods.
Fig. 1 : Energy differences between the α and β phases of p-DIB computed
with PBE, PBE0 and B3LYP with and without the -D and -TS correction.
The DMC result by Hongo et al. (2) is also reported, with error bars,
for comparative purpose.
Fig. 2 : View of the bc plane of the optimized (a) PBE-D (light green sticks)
(b) PBE-TS (blue sticks) α-form of p-DIB molecular crystal superimposed
to the experimental structure (purple sticks). The H-π interaction between an
H atom of the p-DIB molecule and the electron density on the benzene ring
is shown by the black dashed line .
(1) A. Pedone, D. Presti, M. C. Menziani, Chem. Phys. Lett., 2012, 541, 12-15
(2) K. Hongo, M. A. Watson, R. S. Sànchez-Carrera, T. Iitaka, A. Aspuru-Guzik, J. Phys. Chem. Lett., 2010, 1, 1789
(3) A. Tkatchenko, M. Scheffler, Phys. Rev. Lett., 2009,102, 073005
(4) S. Grimme, J. Comput. Chem., 2006, 27, 1787
14
FC 9
Luminescence properties and emission dynamics of YPO4
activated with Tb3+ and Bi3+.
Fabio Angiuli, Enrico Cavalli
Dipartimento di Chimica Generale ed Inorganica, Università di Parma, Parma (ITALY)
*e-mail: [email protected]
Summary
The synthesis of YPO4 both singly doped with Tb3+and co-doped with Bi3+ has been carried out by the Pechini sol-gel method
and solid state reaction. Good quality materials have been obtained in terms of particle size, morphology and of emission
performance. The co-doping with Bi3+ results in a significant increase of the luminescence intensity even upon direct rare earth
excitation. The excited states dynamics of these phosphors have been discussed by taking into consideration the effect of the
presence of Bi3+ on the optical properties of the host lattice.
Introduction
YPO4 is an attractive host lattice for trivalent rare earth ions thanks to its favorable physico-chemical properties like high and
extended transparency, thermal and chemical stability, structural characteristics, and it is extensively investigated in order to
develop phosphors for solid state lighting, PDP technology, etc. [1]. In this work we deal with the spectroscopic properties of
YPO4 activated with Tb3+ and the effect of the Bi3+ co-doping on the emission performances of these systems. The yttrium
phosphate lattice is very suitable for this kind of study since its large bandgap and the absence of host-rare earth energy
transfer facilitate the study of the role of the co-doping ion in the sensitization of the rare earth luminescence.
Materials
The phosphors used in this study have been synthesized by the Pechini sol-gel method and solid state reaction. They have been
characterized by X-ray diffraction and scanning electron microscopy (SEM). The obtained compounds are single phase and
constituted by particles with well defined elongated shape and size distribution in the 200-800 nm range (Fig. 1).
Results and Conclusions
The luminescence spectra of the YPO4:Tb3+(5%), Bi3+(x%) phosphors measured upon direct Tb3+ excitation at 370 nm are
shown in Fig. 2. They are constituted of transitions originating in the 5D4(Tb3+) emitting level, whose intensity progressively
increases with the Bi3+ concentration. In addition it has been observed that: i. The excitation band at 234 nm corresponding to
the Bi3+ absorption is weak, indicating that the Bi3+ĺ7E3+ energy transfer process is not very efficient. ii. The decay profiles of
the 5D4 emission are single exponentials with time constants decreasing as the Bi 3+ concentration increases. This behavior can
be associated to the increase of the radiative emission probabilities.
Fig. 1. SEM image of YPO4:Tb.
Fig. 2. YPO4:Tb emission spectra
References
1. H. Lai, A. Bao, Y. Yang, Y. Tao, H. Yang, Y. Zhang, L. Han, J. Chem. Phys. C 112 (2008) 282.
2. A.S. Korotkov, V. V. Atuchin, Opt. Comm. 281 (2008) 2132.
15
FC 10
Inclusion propensity of new wheel-and-axle complexes based on Ru(II) half-sandwich
units
1
Alessia Bacchi, 2Susan Bourne, 1Giulia Cantoni, 2Gift Mehlana, 1Paolo Pelagatti, 3Silvia Rizzato
1
Dipartimento di Chimica, Università degli Studi di Parma, Parco Area delle Scienze 17/A, Campus, I43124 Parma, Italy.
2
Department of Chemistry, University of Cape Town, Rondebosch 7707, Cape Town, South Africa.
3
Dipartimento di Chimica Strutturale e Stereochimica Inorganica, University of Milan, Via Venezian, 21
Milano, Italy.
[email protected]
In this contribution we present the rationalization of the solid state packing of new metallo-organic
materials with flexible dynamic frameworks, able to create pores on demand to accommodate small guest
molecules. The size and shape of the organic ligands are crucial in determining the inclusion propensity
of these materials, and we focused on wheel-and-axle (waa) systems that are constituted by two bulky
groups (wheels) and a rigid linear spacer (axle) (1).
Here we report the study on systems based on two ruthenium half-sandwich units (HSRu) connected by a
covalent organic ligand; these compounds combine the inclusion properties of the wheel-and-axle
molecular motif with the chemical properties of HSRu complexes, known as catalysts of a variety of
important organic transformations, such as the enantioselective reduction of polar bonds under hydrogen
transfer conditions.
We performed solid/vapour and solid/liquid exchange experiments with different guests to test the
flexibility of the crystalline networks and the robustness of the supramolecular synthons involved;
furthermore, the kinetics of these processes are being studied.
Figure. Example of waa host-guest system (guest in spacefill mode)
(1) Bacchi A.; Carcelli, M.; Chiodo, T.; Mezzadri, F. CrystEngComm. 2008, 10, 1916-1927.
16
ABSTRACTS DELLE COMUNICAZIONI POSTER
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Anand Resmi
Barbalinardo Marianna
Baschieri Andrea
Bertucci Alessandro
Buonfiglio Rosa
Caciolli Lorenzo
Calabrese Camilla
Camborata Cecilia
Caruana Lorenzo
Castellucci Nicola
Cazzato Addolorata Stefania
Cerisoli Lucia
Colliva Carolina
Corrado Sandra
Costantini Cristiana
Cvetkovski Aleksandar
De Lucia Daniela
De Vita Alessandro
Del Cadia Marta
Del Zoppo Luisa
Durso Margherita
Farina Davide
Fasoli Anna
Feng Gang
Foschi Giulia
Freguglia Giada
Giacomini Elisa
Graziosi Riccardo
Greco Arianna
Gualandi Isacco
Gullo Maria Pia
Heidari Mojgan
Hemmatian Zhara
Ianni Cristina
Leonardi Chiara
Leonardi Francesca
Locritani Mirko
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Maestri Valentina
Malisardi Gemma
Marchetti Chiara
Massarenti Chiara
Mazzeo Paolo Pio
Miozzi Michele
Montroni Elisa
Morganti Emanuele
Nanna Saverio
Natali Mirco
Nepovimova Eugenie
Ortelli Simona
Petruzziello Diego
Popovic Mina
Pori Matteo
Prati Federica
Prencipe Francesco Pio
Protti Michele
Qin Wenling
Reggi Michela
Salvatore Elisa
Sammak Susan
Sarti Elena
Scotti Alessandra
Soldà Alice
Soldati Roberto
Speri Enrico
Spinozzi Silvia
Staderini Samuele
Taddia Laura
Veratti Patrizia
Viola Angelo
Zamberlan Francesco
Zangheri Martina
Zanna Nicola
Tassinari Francesco
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Spectroscopic investigation of host-guest interaction of iron trimesate nanoMOF and
azidothymidine derivatives
Resmi Anand1, Francesco Manoli1, Valentina Agostoni2, Francesco Borghi3, 4, Pierluigi Reschiglian3, 4,
Ruxandra Gref2, Sandra Monti1
1
Istituto per la Sintesi Organica e la Fotoreattivita, ISOF-CNR, Bologna, Italy.
2
Universite Paris-Sud, UMR CNRS 8612, Chatenay Malabry, France.
3
Chemistry Department G. Ciamician, University of Bologna, Italy
4
byFlow s.r.l, Bologna, Italy
[email protected]
Metal-organic frameworks (MOFs) are hybrid porous materials where metal ions or small nano
clusters are linked into one-, two- or three-dimensional structures by multifunctional organic linkers.
They are characterized by strong metal-ligand bonds and organized in solution as nanoparticles with
regular cavities. The Fe(III)-carboxylate nanoMOFs also called MIL-100 (Fe(III)3(OH)(H20)2{(CO2)3
C6H3}2) have been synthesized by microwave irradiation by taking advantage of the spontaneous
coordination between Fe3+ WULPHUVDQGWKHRUJDQLFOLQNHUWULPHVLFDFLG7KLV³JUHHQ´WHFKQRORJ\OHDGVWR
the formation of biodegradable, non cytotoxic nanoparticles with mesoporous cages of free apertures of
ca. 25 and 29 Å, accessible through microporous windows of ca. 5.5 and 8.6 Å. Due to their porous
VWUXFWXUH WKH\ DFW DV HIILFLHQW ³PROHFXODU VSRQJHV´ UDSLGO\ entrapping drugs with different polarities,
sizes and functional groups by immercing in corresponding solutions.1, 2
Herein we report the nature of interaction between MIL-100 and 3'-azido-3'-deoxythymidine
(AZT), an important nucleoside analog reverse-transcriptase inhibitor, and its monophosphate (AZT-MP)
and triphosphate (AZT-TP) derivatives, respectively using optical spectroscopic techniques. Among the
investigated drugs the phosphate derivatives show a stronger interaction with MIL-100, most likely due to
the coordination between the drug phosphate groups and the available metal sites. These studies enabled
us to determine the affinity constant around 1000 M-1 between AZT-TP and the Fe(III) trimeric structural
unit. 7KLVKLJKO\YHUVDWLOHDQG³JUHHQ´V\VWHPcan be further applied to deliver other anti-cancer and antiviral phosphorylated nucleosides analogues.
Fe(III)trimesate MOF architecture
AZT-TP
Acknowledgement
7KLVZRUNKDVEHHQFDUULHGRXWLQWKHIUDPHRIWKH(XURSHDQ0DULH&XULH,71³&<&/21´Qo 237962)
(1) Horcajada, P.; Chalati, T.; Serre, C.; et al. Nature Mat. 2010, 9, 172-178.
(2) Horcajada, P.; Surblé, S.; Serre, C.; et al. Chem. Commun. 2007, 43, 2820-2822.
18
P2
Fabrication, characterization and porosity analysis of a scaffold based on a standing
fibrin
1,2
1
M. Barbalinardo, 1 F. Valle, 1,3B. Chelli, 1 E. Bystrenova, 1G. Foschi, 2E. Zanotto and 1 F. Biscarini1
Consiglio Nazionale delle Ricerche (Istituto per lo Studio dei Materiali Nanostrutturati) (CNR-ISMN),
via Gobetti 101, 40129 Bologna, Italy
2
Università di Bologna “Alma Mater Studiorum”, via Zamboni 33, 40126, Bologna, Italy
2
Nano4bio S.R.L., viale G. Fanin 48, 40127, Bologna, Italy
[email protected]
Nanomedicine and tissue engineering attempt to repair or improve the biological functions of tissues that have been damaged
or have ceased to perform their role through three main components: a biocompatible scaffold, cellular component and
bioactive molecules. Brian Wowk says: “Since the human body is basically an extremely complex system of interacting
molecules (i.e., a molecular machine), the technology required to truly understand and repair the body is molecular machine
technology - nanotechnology”. In fact, nanotechnology, using advanced manufacturing techniques such as conventional and
unconventional lithography, allows fabricating supports with various geometries, sizes and displaying physical chemical
properties tuneable over different lengthscales (1).
In this work we report the fabrication of two type of scaffold made of fibrin gel, standing fibrin film and standing fibrin clot,
for the regeneration of tissues that can be applied to various diseases and disorders. We made fibrin gel Film, because we want
to observe behaviour of the growth of cells on random fibrin network. Films of fibrin gel of different thickness have been
fabricated with special attention to the realization of a micro-frame that allows a simple manipulation of the structure. Such a
standing fibrin scaffold prevents the artefacts arising from the interaction of the gel films with other surfaces. We made fibrin
gel CLOT (2) and we stretch the clot because we want to observe if the cells growth and migration is influenced by the
orientation of the fibers of fibrin network (fig.1). The ultrastructure characterization of fibrin network is fundamental for
evaluating its morphology, porosity and biological efficacy, thus we characterized the fibrin films by scanning electron
microscopy (fig.2) and atomic force microscopy. Power spectrum analyses of the images have been performed to provide the
characteristic lengths of the fibrin network. The fibrin scaffold can also be designed bi-functionalized to allow the co-culture of
different cell types on the two sides thus promoting the reconstruction of complex tissues. Then, they may be processed to
fabricate a tubular scaffold.
Fig 1. A) Fibrin gel clot before stretching, B) Fibrin gel clot after stretching.
Fig 2. SEM images of fibrin network A) Random fibrin network (standing fibrin film), B) Orientated fibrin network (standing
fibrin clot), C) Stem cell on fibrin network.
Reference
(1) Valle, F. et al., Advanced Biomaterials 2010, 12, 185-191.
(2) Brown, A.E.X. et al., Science 2010, 325, 741-744.
19
P3
Triple click to tripodal triazole-based ligands. Synthesis and characterization of blueemitting Ce3+ complexes.
Andrea Baschieri, Andrea Mazzanti,Stefano Stagni and Letizia Sambri
Dipartimento di &KLPLFD,QGXVWULDOH³7RVR0RQWDQDUL´University of Bologna
v.le Risorgimento 4, 40136 Bologna, Italy.
[email protected]
7KH UHFHQW DGYDQFH RI ³FOLFN FKHPLVWU\´ KDV ERRVWHG WKH QXPEHU RI PROHFXOHV DYDLODEOH IRU VHYHUDO
leading-edge fields, including medicinal chemistry, biology and material sciences. $PRQJ ³FOLFN´
reactions, the Cu(I)-catalyzed azide alkyne cycloaddition (CuAAC) has received extraordinary attention
since it is the most effective method to afford 1,4-substituted-1,2,3-triazoles from a wide range of usable
substrates, with essentially perfect regioselectivity under mild conditions.
In addition, the development of the CuAAC reaction resulted in an renewed interest toward the
employment of 1,4-functionalized-1,2,3-triazoles in coordination chemistry because of their potential to
act as N-donor ligands. In particular, polydentate ligands can be exploited to coordinate high coordination
number ions such as lanthanides, which possess fascinating and versatile photophysical properties.
Among lanthanides, Cerium is the most abundant of the rare earth elements, one of the least expensive, it
displays low to moderate toxicity and it played an important role in organic synthesis. Furthermore, Ce3+
ion exhibits a 5d±4f emission with a large absorption in the UV region and a short luminescence lifetime
due to allowed electric dipole transitions.[11] Generally, the emission of Ce3+ ion occurs in the UV spectral
region but it can be red-shifted depending on the environment.
Tris(aryl-triazolyl-methyl) amines have been synthesized by a one-pot triple click reaction of azides from
anilines with tris-propargyl amine. The resulting tripodal ligands have been employed to obtain six new
Ce3+ complexes.1 The formation of the new complexes, which were obtained both as heteroleptic or
homoleptic-type, is influenced by the nature of the counterion (nitrate, perchlorate or triflate) of the
starting Ce3+ salts, (Scheme 1).
X
N
N N
X
X
1a X=H
1b X=F
ACN, 0°C
rt, overnight
2)
N
N
N
N
2 3
Na-ascorbate, aq. CuSO4,
rt, 2 days
X
N N
N
NH2 1) t-BuONO, TMSN3
N N
Ce3+
N
N
X
N
N N
X
N
X
L1 X=H, 61% yields
L2 X=F, 67% yields
X
(A- ) 3
N
N
N
N
Ce3+
N
N
N N
N
X X
N
N
N
X
N N
N
4a X=H, A= ClO4
5a X=H, A= CF3SO 3
N
N
N
X
N
4b X=F, A= ClO4
5b X=F, A= CF3SO3
N
O
N
Ce
N
N
O
ON O O OO NO
N
3a X=H
O
3b X=F
Scheme 1. Synthesis of ligands L1 and L2 and complexes 3a-b, 4a-b, 5a-b.
All the new Ce3+-based complexes were found as highly stable both in solution and in the solid state.
Their structural features have been at first studied by NMR spectroscopy. In addition, by combining
experimental and DFT theoretical approaches, the X-ray structure of one heteroleptic complex has been
used for simulating the structures of all the remaining complexes. Finally, both the heteroleptic and the
homoleptic complexes are luminescent, and the analysis of their photophysical properties indicate that the
Ce3+ center rules the occurrence of radiative processes.
(1) Baschieri, A.; Mazzanti, A.; Stagni, S.; Sambri, L. Eur. J. Inorg. Chem. 2012, Submitted.
20
X
P4
Development of new tools for highly specific nucleic acid detection: PNA-modified
photonic crystal fibers and PNA-based switching probes
1
Alessandro Bertucci, 1Alex Manicardi, 1Emanuela Cavatorta, 2Alessandro Candiani, 2Michele Sozzi,
2
Annamaria Cucinotta, 2Sara Giannetti, 2Stefano Selleri, 1Roberto Corradini
1
2
Dipartimento di Chimica, Università di Parma, Parco Area delle Scienze 17/A, 43124, Parma, Italy;
'LSDUWLPHQWRGL,QJHJQHULDGHOO¶,QIRUPD]LRQH8QLYHUVLWjGL3DUPD3DUFRArea delle Scienze 181/A, 43124,
Parma, Italy
[email protected]
Biophotoncs represents a very attractive area of interest integrating ICTs with biological systems and
bioprobes. Peptide nucleic acids (PNAs) are oligonucleotide (ON) mimics that, due to their exceptional
properties in DNA and RNA hybridization and their high chemical and biological stability, are very well
suited for the detection of specific nucleic acid target sequences (1). In this work, novel sensing tools
based on the use of PNA for biophotonic applications and for nucleic acid detection involving switching
probes will be presented. Photonic crystal fibers (PCFs) have the unique feature of presenting a crosssection defined by air-hole arrays running throughout the fiber, allowing to perform internal
functionalization (2). The feasibility of novel specific DNA sensing systems, based on the use of different
kinds of photonic crystal fibers combined with very specific PNA probes is described. The hybrid sensing
element was tested for optical DNA biosensing: changes in the refractive index were monitored by shift
of the reflection band of the Bragg grating inscribed in the fiber itself (2,3). ON-functionalized gold
nanoparticles (ON-AuNPs) were used for signal amplification, exploiting a sandwich-like system once
DNA target was captured by PNA probes. A systematic study on the behaviour of these sensing systems
using targets of relevance in biomedical and food-analysis will be presented.
For diagnostics and biophotonics applications, self-reporting PNA probes can be very useful. In a
disctinct part of the work, the PNA scaffold was used for the design of new switching probes for nucleic
acid recognition on surfaces and in solution (4,5). In particular the interest was put on doubly modified
PNAs bearing two reporter groups; a pyrene-based monomer-excimer probe and a fluorophore-quencher
system based on the presence of the couple fluorescein-dabcyl were obtained. Fluorescent studies
performed on the functionalized PNA monomers showed the formation of the excimer band in case of the
pyrene-modified PNA and suppression of the fluorescein fluorescence in the other, thus demonstrating
the interaction between the group placed on the base and that on the backbone. Doubly modified PNA
sequences were obtained by using solid phase synthesis both for the PNA structure and for the subsequent
modifications. Further studies about hybridization and sensing properties of these novel probes are in
progress.
a)
c)
b)
Fig.1: a) scheme of the linkage of the PNA probe to the fiber internal surface; b) scheme of the sandwich-like system used for
DNA detection; c) scheme of a doubly functionalized monomer inserted in the PNA sequence
(1) Bertucci, A.; Manicardi, A.; Corradini, R. Advanced Molecular Probes for Sequence-Specific DNA Recognition, in: Detection of
non-amplified Genomic DNA, Spoto, G.; Corradini, R. Eds. Springer, Dordrecht, The Netherlands 2012
(2) Corradini, R.; Selleri, S. Photonic Crystal Fiber for Physical, Chemical and Biological Sensing 2010, 80-LQ³3KRWRQLF&\VWDO
)LEHUVIRU3K\VLFDO&KHPLFDODQG%LRORJLFDO6HQVLQJ´3ULVFR0&XWROR$&XVDQR$(GVBentham Publisher, in press
(3) Candiani, A.; Sozzi, M.; Cucinotta, A.; Selleri, S.; Veneziano, R.; Corradini, R.; Marchelli, R.; Childs, P.; Pissadakis, S. IEEE
J.Sel.Top.Quant. 2012, 18, 1176-1183
(4) Corradini, R.; Sforza, S.; Tedeschi, T.; Totsingan, F.; Manicardi, A.; Marchelli, R. Curr. Top. Med. Chem. 2011, 11, 1535-155
(5) Manicardi A.;Accetta A.; Tedeschi T.; Sforza S.; Marchelli R.;Corradini R Artif. DNA PNA XNA 2012, 3, 53-62
21
P5
Towards an ensemble-based Virtual Screening for discovering new LDHA inhibitors
1
Rosa Buonfiglio, 1Maria Ferraro, 1,2Andrea Cavalli, 1Matteo Masetti and 1Maurizio Recanatini.
1
Department of Pharmacy and Biotechnology, University of Bologna,
Via Belmeloro 6, I-40126, Bologna.
2
Department of Drug Discovery and Development, Istituto Italiano di Tecnologia, Via Morego 30,
I-16163 Genova.
[email protected]
Human lactate dehydrogenase (LDH; EC 1.1.27) is responsible for the reduction of pyruvate by NADH to
lactate and NAD+, and assembles in hetero-tetramers based on different subunit (H and M) stoichiometry.
The M4 isoenzyme (also known as LDHA) is mainly found in tissues with anaerobic metabolism such as
skeletal muscle.(1) Since the discovery of its over-expression in many human cancers, LDHA has
emerged as a drug target, but only recently the use of inhibitors was proven to be effective in tumor
regression.(2) A study aimed at identifying different conformations of protein was performed; in
SDUWLFXODUZHZHUHLQWHUHVWHGLQWKHODUJHVFDOHPRYHPHQWRIDDDORRS³DFWLYHVLWH´ORRSZKLFKLV
known to be involved in substrate recognition. Among the different available techniques, hybrid Replica
Exchange (hREMD) method was chosen.(3),(4) 7KHFRPSOHWHWUDQVLWLRQRIWKH³DFWLYHVLWH´ORRSIURPWKH
open to the closed state was also studied with two sets of hREMD simulations, starting from two different
³DFWLYHVLWH´ORRSFRQIRUPDWLRQVDQRSHQDQGFORVHGVWDWHVHOHFWHGIURPWKHFU\VWDOVWUXFture). Network
representations and clustering were used to analyze the conformational ensemble of the mobile loop. In
this scenario, an ensemble-based Virtual Screening could be performed, taking into account protein
flexibility in the search for novel LDHA inhibitors.
(1). Granchi, C.; Bertini, M.; Macchia, M.; Minutolo, F. Curr Med Chem. 2010, 17, 672-697.
(2) Le, A. et al. Proc Natl Acad Sci USA. 2010, 107, 2037-2042.
(3) Sugita, M. Y.; Okamoto, Y. Biopolymers. 2001, 60, 96-123.
(4) Okur, A.; Wickstrom, L.; Layten, M.; Geney, R.; Song, K.; Hornak, V.; Simmerling, C. J Chem Theory Comput. 2006, 2,
420-433.
22
P6
Fluorous affinity chromatography for enrichment and determination of
perfluoroalkyl substances
N. Marchetti1, L. Caciolli1, A. Laganà2, F. Gasparrini2, L. Pasti3, F. Dondi3, A. Cavazzini3, A. Massi3
1
Lab “Terra&Acqua Tech”-Water Quality, Technopole of Ferrara and Department of Chemistry and
Pharmaceutical Science, University of Ferrara, Ferrara, Italy
2
Department of Chemistry, University “La Sapienza”, Rome, Italy
3
Department of Chemistry and Pharmaceutical Science, University of Ferrara, Ferrara, Italy
[email protected]
Perfluorinated alkylated substances (PFAS) are emerging contaminants that include, as major classes,
perfluoroalkyl acids (usually with fluorinated carbon chains of four to sixteen atoms) and their salts
(perfluoroalkyl carboxylates and perfluoroalkyl sulfonates). Intensively used in consumer and industrial
products in the last decades, PFAS are regarded as extremely persistent and highly toxic compounds that
pervasively contaminate the biota (1). Because of the significantly low levels at which PFAS are found in
real samples (typical concentration values are sub- to low-nanograms per liter), analyte enrichment
through solid phase extraction (SPE) is required before analysis(2-4).
The scope of this work is to investigate if fluorocarbon-bonded phases, such as fluorous silica gel, can be
used as a means of preconcentration and analysis of PFAS. The idea is to exploit the unique characteristic
of heavily fluorinated materials, namely the property known as fluorofilicity.
Two different modified stationary phases (pentafluorophenyl-SP and perfluorooctyl-SP) were prepared
and the chromatographic behavior of four perfluoroalkyl acids was studied.
(1) Prevedouros, K; Cousin, I. T.; Buck, R.; Korzeniowski, S.; Envir. Sci. Tech. 2006, 40, 32-34.
(2) Van Leeuwen, S.; de Boer, J.; J. Chrom.A 2007, 1153, 172-185.
(3) Benskin, J.; Bataineh, M.; Martin, J.; Anal. Chem. 2007, 79, 6455-6464.
(4) Washington, J.; Yoo, H.; Ellington, J.; Envir. Sci. Tech. 2010, 44, 8390-8396.
23
P7
The rotational study of a flexible molecule: 2(N)-methylaminoethanol
A challenge for rotational spectrosopy
1
1
Camilla Calabrese, 1Sonia Melandri, 1Assimo Maris
'HSDUWPHQWRI&KHPLVWU\*&LDPLFLDQ´8QLYHUVLW\RI%RORJQD9LD6HOPL,-40126 Bologna, Italy.
[email protected]
Flexible molecules show a complex conformational space, generally shaped by non bonding interactions
occurring within the molecule or with the surroundings and represent therefore a challenge for
computational methods and rotational spectroscopy because of the presence of high number of stable
conformations and large amplitude motions.
We report the rotational study of 2(N)-methylaminoethanol (MAE) performed by Free Jet Absorption
Microwave Spectrocopy (FJAMW). This choice of study the conformational properties of MAE is mainly
due to the fact that aminoethanol and thus also MAE can be considered a precursors of aminoacids in the
interstellar medium (1) and secondly, the methyl-aminoethanol side chain is present in important
biological molecules such as DGUHQDOLQHVRZHFDQFRQVLGHULWOLNHDPRGHOIRUWKHFKDLQ¶VLQWHUDFWLRQV
The high vacuum conditions that we obtained with this technique reproduce those of the interstellar
medium and this makes these kind of experiments very useful to guide astrophysical studies that aim at
finding life precursors. Infact, because of the unique spectral signatures provided by rotational
spectroscopy, much of the chemical inventory of the interstellar medium has been detected using radio
telescopes operating in the centimeter and millimeter wavelenghts regions (2). Moreover the unusual
chemical environments in this spatial region can produce novel chemical reaction processes, that involve
less stable conformational species.
H
W
O
H
H
W
C
C
W
H
H
C
N
H
H
H
H
The conformational preferences of MAE are dominated by the intramolecular hydrogen bond between the
OH and NH2 groups. The high flexibility of this molecule involves a complex energy potencial surface
with a large numer of possible stable conformations. Infact for MAE 24 stable conformations have been
predicted and two conformers were observed by FJAMW spectroscopy with our 60-72 GHz spectrometer.
With respect to a previous study (3) we have extended the frequency range to 72 GHz and partly
reassigned the rotational spectrum of one of the conformers.
(1) S. Charnley , in Proceedings of the workshop: The bridge between the Big Bang and Biology, CNR, Italy 1999.
(2) J. L. Neill et all., J. Phys. Chem. A, 2011, 115 (24), pp 6472±6480.
(3) R. E. Penn and L.W. Buxton, J. Mol. Spectrosc. 56, 229, 1975.
24
P8
RELATIONSHIP BETWEEN STRUCTURE, PHYSICAL-CHEMICAL
PROPERTIES AND BIOLOGICAL ACTIVITY OF NATURAL BILE ACIDS AND
THEIR SYNTHETIC ANALOGUES
C. Camborataa C. Collivaa, S. Spinozzia, R. Aldinib, M. Montagnanib, R. Pellicciaric, A. Rodaa
a
Department of Chemistry ³*. &LDPLFLDQ´, University of Bologna, Via Selmi 4, 40126, Bologna, Italy
b
Department of Clinical Medicine, University of Bologna, Via Massarenti 9, 40138, Bologna, Italy
c
Department of Chemistry and Drug Technologies, University of Perugia, Via del Liceo 1, 06123,
Perugia, Italy
[email protected]
Bile acids (BAs) are the final products of cholesterol catabolism representing its main excretory pathway.
BAs are signaling molecules interacting with Farnesoid X receptors (FXR) initiating events that reduce
the transcription and activity of the rate-limiting enzyme in BAs synthesis, cholesterol 7Į-hydroxylase
(CYP7A1). Among natural BA the most potent is chenodeoxycholic acid (CDCA); a new synthetic
analogues Į-ethyl chenodeoxycholic acid (6ECDCA) exhibits much more activity (1). More recently it
has been found that BAs increase energy expenditure acting also as ligands (agonist) of G proteincoupled receptor TGR5, with activation in enteroendocrine cells stimulates secretion of the incretin
glucagon-like peptide-1 (GLP-1), a validated target in the treatment of type 2 diabetes, suggesting
beneficial effects in the control of glucose metabolism. The most active natural BA is cholic acid (CA)
and a new synthetic analogue 6Į-ethyl-23 (S) methyl cholic acid (6EMCA) shows a much more agonist
activity (2). These new synthetic analogues represent a source as promising novel drugs for the treatment
of hepatic and metabolic diseases. As a detergent-like molecules BAs pharmacological activity is highly
structure-related because small changes in their structure can modify significantly their physical chemical
properties in aqueous solution and therefore their biodistribution and metabolism. Accurate
methodologies to study their detergency, solubility, lipophilicity and binding affinity with serum albumin
have been developed and optimized. On the mean time a suitable animal model has been used to define
the relationship between structure and intestinal absorption, metabolism and hepatic uptake XVLQJ³bile
fistula rats´ (3) where BA are acutely administered (1μmol/Kg/min for 1 hour) through duodenal and
femoral infusion. An accurate and sensitive HPLC-ES-MS/MS has been developed and validated. HPLC
separation was achieved by RP on a Phenyl-hexyl column and the MS detection was performed by
Multiple Reaction Monitoring (MRM) operating in the negative ionization mode. Analysis was done with
adequate sensitivity (LLOQ = 0.01μM) also in biological matrices (like blood) for which a pretreatment
has been optimized. The physical-chemical properties of the studied BAs are reported in the table:
Ws: water solubility about AB as protonated species;
CMC: Critic micellar concentration determinated in 0,15 M NaCl;
STCMC: Superficial Tension at CMC in 0,15 M NaCl;
LogPA-: partition coefficient octanol/water of BAs as ionized species;
Small variation in BA structure as the introduction of an Ethyl group in 6 position are able to increase the
lipophilicy of the molecule and this account for a different intestinal absorption and hepatic metabolism.
These data are necessary to properly design new analogues and usefull to predict their in vivo
pharmacokinetic and activity.
[1] Bile Acid Derivatives as Ligands of the Farnesoid X Receptor. Synthesis, Evaluation, and Structure-Activity Relationship
of a Series of Body and Side Chain Modified Analogues of Chenodeoxycholic Acid. R. Pellicciari,, G. Costantino, E.
Camaioni, B.M. Sadeghpour, A. Entrena, T. M. Willson, S. Fiorucci, C. Clerici, and A. Gioiello. J. Med. Chem. 2004, 47,
4559-4569
[[email protected] 'LVFRYHU\ RI Į-Ethyl-23(S)-methylcholic Acid (S-EMCA, INT-777) as a Potent and Selective Agonist for the TGR5
Receptor, a Novel Target for Diabesity. R Pellicciari, A Gioiello, A Macchiarulo, C Thomas, E Rosatelli, B Natalini, R
Sardella, M Pruzanski , A Roda , E Pastorini , K Schoonjans and J Auwerx, Journal of Medicinal Chemistry, 2009, 52, 7958±
7961
[3] 23-Methyl-3Į,7ȕdihydroxy-5/3-cholan-24-oic id dose-response study of biliary secretion in rat. A Roda , R Aldini, B
Grigolo, P Simoni, E Roda, R Pellicciari, PL Lenzi, and B Natalini, Hepatology, 1988, 8 1571-1576.
25
P9
Chiral phosphoric acid catalyzed highly enantioselective vinylogous Povarov reaction
Luca Bernardi, Mariafranscesca Fochi, Lorenzo Caruana.
'HSDUWPHQWRI,QGXVWULDO&KHPLVWU\³Toso Montanari´6FKRRORI6FLHQFH$OPD0DWHU6WXGLRUXP±
University of Bologna, V. Risorgimento 4, 40136, Bologna, Italy
[email protected]
The Povarov reaction is an inverse-electron-demand [4 + 2] cycloaddition between an electron rich olefin
(dienophile) and an N-arylimine (diene) (1). This transformation represents one of the most versatile
routes to 1,2,3,4-tetrahydroquinolines, heterocyclic compounds which exhibit interesting biological
activity (2). For this reason, this reaction has been recently thoroughly investigated, even in its catalytic
asymmetric version, by using vinylethers, vinylindoles, and enecarbamates as dienophile partners (1a).
We recently found that 1,3-butadiene-1-carbamates can be productively engaged in a catalytic
asymmetric Povarov reaction with their terminal olefin (see Figure). Thus, the nucleophilic reactivity of
the enecarbamate moiety propagates through the S-system, rendering possible the development of the first
catalytic asymmetric vinylogous Povarov reaction. A phosphoric acid derived from (R)-octahydroBINOL, catalyzes this reaction affording target products in good yields, complete diasteroselectivities and
excellent enantioselectivities (>98% ee in most cases). This allows the preparation of novel
1,2,3,4tetrahydroquinolines bearing an enecarbamate moiety at C-4, which might serve as versatile handle
for further synthetic transformation.
Bibliography.
(1) (a) Vellaisamy, S.; Padmakar, A.; Suryavanshi; Menéndez, J. C., Chem. Rev., 2011, 111, 7157; (b) Kouznetsov, V. V.,
Tetrahedron, 2009, 65, 2721.
(2) Katritzky, A. R.; Rachwal, S.; Rachwal, D., Tetrahedron, 1996, 52, 15031.
26
P 10
Conformational Studies of Phe-rich foldamers by VCD spectroscopy and
ab-initio calculations
Nicola Castellucci, Claudia Tomasini*
'LSDUWLPHQWRGL&KLPLFD³*&LDPLFLDQ´- Alma Mater Studiorum Università di Bologna Via Selmi 2, I±40126 Bologna (Italy)
[email protected]
Foldamers are oligomers that adopt specific and stable conformations similar to those typical
of proteins and nucleic acids. Our group has extensively studied the conformational behaviour
of oxazolidin-2-one (Oxd) containing foldamers. [1]
+HUHLW¶VVKRZQ the synthesis and the conformational analysis in solution of a series of hybrid
oligomers that have general formula Boc-(L-Phe-L-Oxd)n-OBn (with n = 1, 2, 3, 4, 6). These
compounds are possible models for the study of amyloid fibers, that are constituted by
peptides and are responsible of several neurodegenerative diseases, like Alzheimer and
Parkinson disease. These peptides are often rich in Phe residues, are poorly soluble and tend
to lie in a very stable ȕ-sheet structure.
H
N
O
O
Ph
O
O
N
O
OBn
O
n
Boc-(-L-Phe-L-Oxd)n-OBn
The conformational analysis has been carried out by 1H NMR, IR, ECD (electronic circular
dichroism) and VCD (vibrational circular dichroism) spectroscopy, accompanied by detailed
ab-initio DFT computational analysis calculations for Boc-L-Phe-L-Oxd-OBn. The latter two
techniques can be very useful in the determination of the preferred secondary structure of this
class of foldamers.
VCD technique has been applied here for the first time to study these foldamer systems and
suggests the formation of a PPII structure. [2]
References
[1] C. Tomasini, G. Angelici and N. Castellucci, Eur. J. Org. Chem., 2011, 3648-3669.
[2] G. Longhi, S. Abbate, F. Lebon, N. Castellucci, P. Sabatino and C. Tomasini, J. Org. Chem., 2012, 60336042
27
P 11
Development of a new sensitive LC-MS/MS method for the determination of
pharmacokinetics and pharmacodynamics of 7-chloro-5-(3-furanyl)-3-methyl-4H1,2,4-benzothiadiazine 1,1-dioxide
A. S. Cazzatoa, G. Cannazzaa, Umberto M. Battistia, C. Parentia, D. Braghirolia , S. Guiduccib , M. Zolib
a-Dipartimento di Scienze della Vita, Università di Modena e Reggio Emilia, Via Campi 183, 41125
Modena, Italy
b- Dipartimento di Scienze Biomediche, Metaboliche e Neuroscienze, Università di Modena e Reggio
Emilia, Via Campi 287, 41125 Modena,Italy
[email protected]
A liquid chromatography tandem mass spectrometry (LC/MS/MS) method has been developed for the
quantitative analysis of acetylcholine (ACh), dopamine (DA) and serotonin (5-HT) in mice brain
microdialysates. The separation of analytes from endogenous compounds and Ringer’s salts was achieved
with a fluorinated stationary phase HSF5 Supelco (15cm x 4,6mm, 5μm particles).
Optimization of chromatographic and mass spectrometry parameters were performed in order to improve
sensitivity of the method. The lower limit of quantification (LLOQ) was 25 pM within a linear range of
0.050–100 nM. The inter-day and intra-day accuracy and precision were within ±10%. The method was
fully validated for its sensitivity, selectivity, matrix effect and stability studies. It was successfully applied
to measure quantitatively acetylcholine, dopamine and serotonin in nucleus accumbens of freely moving
mice after different stimuli such as cocaine and amphetamine injections, indicating that our LC/MS/MS
assay is an effective method for the determination of these neurotransmitters (1). This method has been
applied to evaluate also the effect of intraperitoneal administration of 7-chloro-5-(3-furanyl)-3-methyl4H-1,2,4-benzothiadiazine 1,1-dioxide, an AMPA receptor positive modulator on the release of ACh, DA
and 5-HT in mice brain by microdialysis technique. Moreover, the concentrations of the administered
drug and its possible metabolites were evaluated in the same microdialysates samples by a previous
developed LC-MS/MS method. The identity of the compounds was confirmed by comparing their
retention times and their MS/MS profiles after injection of the corresponding synthetic authentic
compounds in the HPLC system. The time course of free drug in the targeted brain region provided a
biophase
pharmacokinetic
(PK)
information
(2)
which
was
used
to
evaluate
pharmacokinetic/pharmacodynamic (PK/PD) relationship by comparing the time course of free drug
versus biomarkers.
(1) Giuseppe Cannazza, Marina M. Carrozzo, Addolorata S. Cazzato, Irina M. Bretis, Luigino Troisi, Carlo Parenti,
Daniela
Braghiroli,
Stefania
Guiducci,
Michele
Zoli
J.
Pharm.
Biomed.
Anal.
2012,
http://dx.doi.org/10.1016/j.jpba.2012.08.004.
(2) Umberto M. Battisti, Krzysztof Jozwiak, Giuseppe Cannazza, Giulia Puia, Gabriella Stocca, Daniela Braghiroli, Carlo
Parenti, Livio Brasili , Marina M. Carrozzo, Cinzia Citti, Luigino Troisi Medicinal Chemistry Letters 2012, Vol. 3, 25-29.
28
P 12
Hydrogenation of Calix[4]pyrrole
Lucia Cerisoli,a Diego Savoia,a Guillaume Journot,b Reinhard Neierb
a
'LSDUWLPHQWRGL&KLPLFD³*&LDPLFLDQ´8QLYHUVLWjGL%RORJQD,WDO\(-mail: [email protected]
b
Institut de Chimie, Université de Neuchâtel, Switzerland, E-mail: [email protected]
The readily available Calix[4]pyrrole emerged as the most popular nitrogen containing macrocycle over
the last decades mainly because of its application as anion sensors which has been thoroughly studied.1
Our group was involved on the reduction of Calix[4]pyrrole which could affords the corresponding
Calix[4]pyrrolidine (3) and/or Calix[2]pyrrole[2]pyrrolidine (1, 2). A recent investigation on Pd-catalyzed
hydrogenation of Calix[4]pyrrole led to surprising results where the nature of the matrix and the amount
of catalyst strongly affect the ratio of final products (1, 2, 3).2,3
1
Guo Z., Sadler P.J., Angew. Chem. 1999, 111, 1610; Angew. Chem. Int. Ed. 1999, 38, 1512
2
Blangy V., Heiss C., Khlebnikov V., Letondor C., Stoeckli-Evans H., Neier R., Angewandte, 2009, 48, 1688-1691.
3
Journot G., Letondor C., Neier R., Stoeckli-Evans H., Savoia D., Gualandi A., Chemistry, 2010, 16, 4224-4230.
29
P 13
Rapid detection of pathogen bacteria and differentiation of viable and dead cells by a
MOS-array olfactory sensor combined with field flow fractionation technology
Carolina Colliva1, Barbara Roda1, Mara Mirasoli1, Massimo Di Fusco2, Pierluigi Reschiglian1, Aldo
Roda1
1
2
'HSDUWPHQWRI&KHPLVWU\³*&LDPLFLDQ´8QLYHUVLW\RI%RORJQD9LD6HOPL%RORJQD,WDO\
Advanced Applications in Mechanical Engineering and Materials Technology Interdepartmental Center
for Industrial Research, University of Bologna, Bologna, Italy
[email protected]
Selective detection of viable and non viable pathogen bacteria is one of the more actual bioanalytical
challenges in life, food and environmental sciences, necessary for a more accurate bacteria infection
detection and monitoring. Despite their sensitivity and selectivity, analytical technologies based on
specific antibodies against bacteria protein epitopes or nucleic acid methods cannot distinguish between
live and dead cells and false-positive results could be obtained in those samples characterized by a high
number of dead cells (e.g., pasteurized milk) [1]. The metabolome approach can be pursued employing
electronic olfactory system composed by an array of six MOS (metal oxide semiconductor) sensors
(EOS-835, SACMI, Imola, Italia), which can detect and classify volatile components specifically
produced by each bacterium. Moreover this system cannot be directly applied in a complex mixture and
bacteria should be partially separated. To improve selectivity i.e. to detect only cells with metabolic and
respiratory activity, we propose the use of EOS-835 combined with field-flow fractionation (FFF) a
separative technique suitable for the non invasive fractionation of live/dead cells based on their
morphological features (shape, size, density, surface properties) [2]. The EOS-835 is able to produce a
GLVWLQFWUHVSRQVHVLJQDWXUHIRUHDFKEDFWHULDOVDPSOHUHVXOWLQJLQD³VPHOOILQJHUSULQW´ZKLFKFDQEHXVHG
for sample identification after multivariate chemometric data analysis. The on-line combination of FFFEOS was exploited to achieve selective detection of a given bacteria in the presence of other strains and
to distinguish, within a given bacteria strain, between viable and non-viable cells. Escherichia coli
O157:H7 and Yersinia enterocolitica in Luria Bertani (LB) were used as model samples then the method
has been applied to pasteurized milk sample containing viable and non viable bacteria strain. Bacteria
exhibit different retention on FFF and fractions corresponding to the retention time for the given bacteria
species were collected, and analyzed with the EOS-835 (analysis time 2h at 37°C). Once validated the
system by a training set using suitable mixtures of viable bacteria, non-viable and mixing the two, the
system was applied to bacteria detection in pasteurized milk. The sensors response data were analyzed
using a chemometric approach with PARVUS software (www.parvus.unige.it). Hybrid chemometric
analysis of Linear Discriminant Analysis (LDA) with Principal Component Analysis (PCA), acronym
(PCA-DA), has allowed us to obtain the following results:
PCA
PCA-DA
SAMPLE
% CUMULATIVE OF FIRST TWO
ABILITY OF CORRECT
ABILITY OF CORRECT
PRINCIPAL COMPONENTS
CLASSIFICATION %
PREDICTION %
E. coli viable/non-viable
92
100
97
Y.enterocolitica viable/non-viable
96
100
100
E. coli/Y. enterocolitica viable
78
100
90
E. coli/Y. enterocolitica non-viable
92
100
100
The data in the table show that the developed model presents excellent ability of classification and
prediction even in real matrix, as they are respectively DQG• 90%.
In conclusion, the combined FFF-EOS system proved able to distinguish between different pathogen
bacteria species and to separate and differentiate, within the same strain, viable and non viable bacteria.
The method can be used in complex food matrices such as milk, with a analysis time of 3 hours, and
without the need of sample enrichment.
References
[1] T. Soejima, F. Schlitt-Dittrich, S. Yoshida, Anal. Biochem., 2011, 418, pp 286±294.
[2] P. Reschiglian, A. Zattoni, B. Roda, E. Michelini, A.Roda, TRENDS Biotechnol., 2005, 23(9), pp 475-483.
30
P 14
SPIROXATRINE ANALOGUES AS POTENTIAL NOCICEPTIN/ORPHANIN FQ
RECEPTOR LIGANDS: SYNTESIS AND PHARMACOLOGICAL STUDIES
S. Corrado1, U. Battisti1, C. Sorbi1, D. Malfacini2, G. Calò2, L. Brasili1, A. Tait1
1
Faculty of Pharmacy, Department of Life Sciences, University of Modena and Reggio Emilia, via G. Campi
183, 41125, Modena, Italy;
2
Department of Experimental and Clinical Medicine, Section of Pharmacology, University of Ferrara, Via
Fossato di Mortara 17-19, 44121, Ferrara, Italy.
[email protected]
The neuropeptide nociceptin/orphanin FQ (N/OFQ) was identified in 1995 as the endogenous ligand for
N/OFQ peptide (NOP) receptor, a deorphanized member of the G protein-coupled receptor superfamily with
a high degree of structural homology (~ 60%) to the classical opioid receptors μ, δ and κ (1).
N/OFQ-NOP system plays a key role in pain transmission, among other biological functions both at central
and peripheral levels. Therefore, the discovery of N/OFQ and NOP offers a new option for the development
of new efficacious and safer analgesic agents than opiates for the treatment of acute and chronic pain (2).
The confirmed affinity towards NOP receptor of the α2 adrenergic and 5-HT1A partial agonist Spiroxatrine
(Ki= 127 nM) (3) has led us to the synthesis of a series of novel and optimized analogues based upon the
spiropiperidine core (scheme 1). At first, we replaced the 1,4-benzodioxane moiety of spiroxatrine with the
chroman-4-one moiety, to give compound 1. This lead has been modified in order to perform preliminary
SAR studies, in particular positions 2, 3 and 4 of chroman core were explored as possible sites to connect
spiropiperidine portion (scheme 1). All synthesized compounds were evaluated at the recombinant human
NOP using a calcium mobilization assay (4).
O
O
O
N
4
O
NH
N
O
N
3
2
O
X
NH
O
N
N
N
O
1
NH
X: C=O, OH
Spiroxatrine
R
X
OH
O
N
O
NH
N
O
R1
O
N
X: F, H
R, R1: CH3, H
O
N
NH
N
R1 R R
R
(n)
R
X
R
NH
N
X: C, O
n: 0,1,2
R: OCH3, H
Scheme 1: Spiroxatrine and example of some synthesized derivatives.
References:
(1) ZAVERI, N. Life Science. 2003, 73, 663-678;
(2) LARGENT- MILNES, T.M.; VANDERAH. T. W. Expert Opin. Ther. Patents. 2010, 20(3), 291-305;
(3) CALO’, G.; BIGONI, R.; RIZZI, A.; GUERRINI, R.; SALVADORI, S.; REGOLI, D. Peptides. 2000, 21(7), 935-947.
(4) CAMARDA, V.; FISCHETTI, C.; ANZELLOTTI, N.; MOLINARI, P.; AMBROSIO, C.; KOSTENIS, E.; REGOLI, D.;
TRAPELLA, C.; GUERRINI, R.; SEVERO, S.; CALO’, G., Naunyn Schmiedebergs Arch Pharmacol. 2009, 379, 599-607.
31
P 15
DESIGN AND SYNTHESIS OF POTENTIAL MITOCHONDRIAL TARGETED
DRUGS ACTIVE ON HSP 90
C. Costantini, R. Rondanin, R. Barucchello, D. Simoni, P. Marchetti
Dipartimento di Scienze Farmaceutiche, Università di Ferrara, 44100 Ferrara, Italy
[email protected]
Among the various targets nowadays studied in human cancer therapy, particular attention has been paid on
molecular chaperons such as heat shock protein 90 (Hsp90) that play a key role in the conformational maturation,
stability and function of other “client” protein substrates within the cell. (1,2)
Many of the client proteins of Hsp90 are involved in signal transduction, cell cycle regulation and apoptosis,
including kinases, transcription factors and hormone receptors. The dysregulation of pathways involving these
proteins are commonly associated with cancer pathology and Hsp90 thus plays a key role in assisting survival,
proliferation, invasion, metastasis and angiogenesis, which represent the hallmark traits of malignancy.
On these basis, previous synthetic efforts allowed our research group to obtain a class of highly active compounds
as inhibitors of Hsp-90. (3)
Other literature data show that molecular chaperons are also abundantly expressed in the mitochondria, that have
recently emerged as intriguing targets for anticancer drugs. (4)
They are important because involved in numerous metabolic reactions and regulate a variety of cellular functions
including proliferation, differentiation and apoptosis.
Our present idea is to elaborate products from structures already known active as inhibitor of Hsp-90 and Trap-1
(5), to make them enter into the mithocondrion.
This possibility comes from the particular features of mithocondria cell wall, with many negative charges, so
interacting well with a type of molecules presenting opposite charges, and favoring their delivery into the
mithocondrion.
For this purpose, we have chosen to bind a scaffold known to interact with Hsp-90 with a polyamine appendage
which, in physiological condition, has already been reported to direct molecules to the cell wall of mithocondria.
(6) Some structures representative of this series are the subject of preliminary tests to assess its biological activity.
A further introduction of a fluorescent moiety is under evaluation to detect the real distribution into the cell of the
most active derivatives.
O
HO
HN
OH
O N
N
H
N
H
H
N
NH2
CONHEt
References
(1) Young, J. C.; Agashe, V. R.; Siegers, K.; Hartl, F. U. Pathways of chaperone-mediated protein folding in the cytosol. Nat.
ReV. Mol. Cell Biol. 2004, 5, 781–789.
(2) Mosser, D. D.; Morimoto, R. I. Molecular chaperones and the stress of oncogenesis. Oncogene 2004, 23, 2907–2918.
(3) Baruchello, R.; Simoni, D.; Grisolia, G.; Barbato, G.; Marchetti, P.; Rondanin, R.; Mangiola, S.; Giannini, G.; Brunetti, T.;
Alloatti, D.; Gallo, G.; Ciacci, A.; Vesci, L.; Castorina, M.; Milazzo, F. M.; Cervoni, M. L.; Guglielmi, M. B.; Barbarino, M.;
Fodera, R,.; Pisano, C.; Cabri, W. Novel 3,4-Isoxazolediamides as Potent Inhibitors of Chaperone Heat Shock Protein 90. J.
Med. Chem. 2011, 54, 8592-8604
(4) Kang, B. H.; Tavecchio, M.; Goel, H. L.; Hsieh, C. C.; Garlick, D. S.; Raskett, C. M.; Lian, J. B.; Stein, G. S.; Languino, L.
R.; Altieri, D. C. Targeted inhibition of mithocondrial Hsp90 suppresses localised and metastatic prostate cancer growth in a
genetic mouse model of disease. Br. J. Cancer, 2011, 104, 629-634
(5) Landriscina, M.; Amoroso, M. R.; Piscazzi, A.; Esposito, F. Heat shock proteins, cell survival and drug resistance: The
mitochondrial chaperone Trap-1, a potential novel target for ovarian cancer therapy. Gynecologic Oncology, 2010, 117, 177182
(6) Melchiorre, C.; Bolognesi, M.L.; Minarini, A.; Rosini, M.; Tumiatti, V.; Polyamines in Drug Discovery: From the
Universal Template Approach to the Multitarget-Directed Ligand Design Strategy. J. Med. Chem. 2010, 53, 5906-5914
32
P 16
Preliminary Screening for Cocrystallization of Methylxanthine Class of Drugs:
Caffeine and Pentoxifylline
Aleksandar Cvetkovski, Valerio Bertolasi, Paola Gilli
Dipartimento di Scienze Chimiche e Farmaceutiche e Centro di Strutturistica Diffrattometrica,
Università di Ferrara,
Via L. Borsari 46, 44121 Ferrara.
[email protected]
Methylxanthines are a group of drugs encompassing the compounds which are purine bases
widely used as drugs that improve peripheral circulation of blood vessels toward the diverse mechanisms
of action (1). The very common use of caffeine and pentoxifylline in therapies, each of them combined
with many other drugs and drug supplements for improving peripheral blood circulation raises the
attention for screening cocrystals of these drugs (2).
During the last years, an increased interest for research in pharmaceutical cocrystals has been
registered, using different strategies. A promising approach is to make use of the molecular recognition
properties of the functional groups and their allocations in entire structures of the molecules which,
depending on the polarity and atom’s electronegativity, are linked one to another by H-bonds (3). Hence,
cocrystals represent multicomponent complexes where the Charge Transfer (CT) or Electron DonorAcceptor (EDA) Interactions between two different molecules may determine the crystal packing that
influences the solid-state properties of the cocrystal itself, and consequently the biopharmaceutical profile
of the API included in the pharmaceutical cocrystals (4).
For the purpose of this initial screening of cocrystallization of the methylxanthine derivatives
caffeine and pentoxifylline, three different types of Cocrystal Formers (or coformers, CF) [acetylsalicylic
acid (ASA), alpha-Lipoic acid (ALA) and p-Coumaric acid (PCA)] have been selected on the base of
their very common use in therapy in association with caffeine and pentoxifylline, respectively, as well as
of the matching of proton acceptor/donor groups for each methylxanthine derivative with each of the
three selected CFs.
Observation of the cocrystallized samples done by using Microscopy, and gained Raman and FTIR Spectra indicate the formation of a new solid crystalline phase that is different from the solid phases of
the starting substances prior the cocrystallization procedure. In addition, assignation of Raman and FT-IR
spectra of the pure starting substances and their cocrystalized samples imply formation of cocrystals.
Further characterization of solid crystalline phases by using Single Crystal Diffractiometry is expected to
solve their crystal structures and to confirm the cocrystal formation.
(1)
(2)
(3)
(4)
Dhaliwal, G.; Mukherjee, D. Int. J. Angiol. 2007, 16(2), 36–44.
Gresele, P.; Momi, S.; Falcinelli, E. Br. J. Clin. Pharmacol. 2011,72 (4) , 634–646.
Dunitz, J. D. CrystEngComm 2003, 5, 506
Bertolasi, V.; Gilli, P.; Gilli, G., Cryst. Growth Des. 2012, 12, 4758−4770
33
P 17
Extraction and Characterization of complex oligosaccharides from Adansonia
digitata (Baobab) fruit pulp by HPTLC-AMD and HPLC
1
De Lucia Daniela;2Bernardi Tatiana; 1,3 Vertuani Silvia; 1,3 Manfredini Stefano
1. Department of Pharmaceutical Sciences, University of Ferrara, via Fossato di Mortara 17-19, 44100
Ferrara, Italy
2. Department of Chemistry, University of Ferrara, via Luigi Borsari 46, 44100Ferrara, Italy
3. Ambrosialab S.r.l, via Mortara 171, 44121 Ferrara, Italy
[email protected]
Key words: Olygosaccharides, Adansonia digitata, HPTLC-AMD, HPLC
Abstract:
The African baobab is a plant from Bombacaceae family, gender Adansonia, specie Digitata. It spontaneusly grows
in Africa (1 specie), in Australia (1 specie) and in Madagascar (6 species), the various species differs for the
morphological characteristics of the flower. The Adansonia Digitata fruit pulp is mainly used as food due to his
high nutritional properties, (energetic value 200Kcal/100g, 836 KJ/100g). Baobab fruit pulp is 10-45 cm long and
8-15 cm large , it is covered by an hard shell, the shell has an ovoid or cylindrical irregular shape.
It is composed by a ligneous , hard and capsule-shape epicarp , it is also covered by green-yellow hair , the
endocarp of the fruit constitutes its pulp.
The endocarp of ripe Baobab fruit appears whitish dehydrate and powdered, and it has a characteristic acidic taste
due to the presence of organic acids such as : citric acid, tartaric acid, malic acid and succinic acid.
In this study: the Adansonia digitata spray dried fruit pulp was characterized in term of oligosaccharides content by
high performance thin layer chromatography (HPTLC) and high performance liquid chromatography (HPLC). The
samples analyzed were prepared following new extracting procedures and widely accepted ones [1,2]. The samples
were analyzed before and after hydrolytic treatment trough hydrocloric acid and sulfuric acid to identify the
monosaccharides building the oligosaccharides structure. During exploration of dietary fibers content of Adansonia
Digitata we have seen an unexpected result. In this study we present our work about identification and
quantification of oligosaccharides in baobab fruit pulp. First extractions with ethanol or methanol solvent by proved
method had provided only sucrose, glucose and fructose. For this reason the next approach to see oligosaccharides
in matrix could be an enzymatic via and subsequent acid hydrolysis.
High performance thin-layer chromatography combined with HPLC showed every oligosaccharides and saccharides
results.
(1) Rank Davis, Leon A. Terry, Gemma A. Chope, and Charl F.J. Faul, Effect of Extraction Procedure on Measured Sugar,
Concentrations in Onion (Allium cepaL.) Bulbs.
J. Agric. Food Chem. 2007, 55, 4299-4306 4299.
(2) Laura Jaime, FranciscoMartı´nez, Maria A Martı´n-Cabrejas, Esperanza Molla´, Francisco JLo´pez-Andre´u, Keith W
Waldron and Rosa M Esteban
“Study of total fructan and fructo oligosaccharide content in different onion tissues”
Sci Food Agric 81:177±182(online: 2000).
34
P 18
Targeted Polymeric Nanoparticles loaded Nutlin-3a vs cancer; optimization of
formulative parameters
A. De Vita, B. Ruozi, G. Tosi, F. Forni, M.A. Vandelli
University of Modena and Reggio Emilia, Department of Life Sciences, via Campi 183, 41124 Modena,
Italy.
[email protected]
Recently, an increasing attention has been given to the anti-cancer drug Nutlin-3a, a low MW molecule
antagonist of murine double minute 2 (MDM2) that actively inhibits p53–MDM2 interaction.
Reactivating p53 function by Nutlin-3a thus provides a promising therapeutic strategy for the treatment of
cancer (1). Unfortunately, Nutlin-3a is poorly soluble in aqueous buffers and shows low bioavailability,
nonspecific delivery, and, most importantly, it is a substrate of multidrug resistance protein. To face with
these limits and to improve the in vivo delivery and efficacy of the antitumoral treatment aiming to
develope an innovative therapy, we evaluate the possibility to use poly(lactide-co-glycolide) (PLGA)
nanoparticles conjugated with anti-CD20 (Rituximab) monoclonal antibodies as vehicle of the drug.
PLGA polymer are FDA-approved; its biodegradability, biocompatibility, biodegradation kinetics,
mechanical properties are well-known and therefore it is one of the most utilized polymers for the
preparation of drug delivery systems.
The encapsulation efficiency of unstable amphiphilic drugs into nanoparticles is frequently unsatisfying
due to the operative conditions required during formulation by using conventional and well documented
methods such as nanoprecipitation or emulsion technique (2,3). We chose to optimize the encapsulation
of Nutlin-3a into PLGA nanoparticles by using single emulsion methods (O/W); in the first step, the
operative conditions such as volume of aqueous phase, the ratio between organic phase and aqueous
phase, the output and time of sonication were tested. Moreover, the purification procedure, designed to
remove the residual surfactant (PVA), and the lyophilization conditions, needed to have a stable and well
re-suspendible product (type and concentration of cryoprotector), were investigated. Stable
nanoemulsions and subsequently homogeneous nanoparticles were formed maintaining a volume ratio 1:4
(organic/aqueous phases) and applying a low sonication output potency (55 Watt) for 1 min. The size (Z
average) of this sample was 188±6 nm with the polydispersity index (PDI) value of 0.08 ± 0.03. The
surface charge (Z-potential) ranged from -3 to -7 mV. The microscopical evaluation confirmed the
homogeneity of this sample. The centrifugation at 15000 rpm for 10 min lead to both a good purification
and easily re-suspension of pelleted nanoparticles. The residual amount of PVA was calculated in the
range of 8-10% w/w for all the preparations. Only trehalose, added at the ratio between 1:0.5 and 1:1
polymer/cryprotector, was able to preserve the formulation integrity, stabilizing nanoparticles during the
process and thus ensuring an acceptable re-suspension in water (Z average close to 300 nm, PDI of 0.4) .
By using the standardized conditions, we formulated PLGA nanoparticles and Rituximab (antihumanCD20 antibody) engineered nanoparticles with and without Nutlin-3a. Rituximab engineered NPs
were prepared starting from PLGA NPs and adapting a well known methodologies for Ab-surface
engineering of NPs (4,5) exploting carboxylic groups reactivity of NPs and free primary amine groups of
the antibody. By using several appropriate techniques and combining the morphological and the
scattering analysis we defined the conjugation of Rituximab on nanoparticles surface. By using ESCA
analysis, we defined the percentage of derivatization up to a value of about 7 %, supporting and
suggesting the possibility to obtain targeted carriers able to deliver the antineoplastic drug to selected
cells. The nanoparticles loaded with Nutlin-3a were feature by a good drug content (at about 5 mg/10 mg
of formulation) and encapsulation efficiency (close to 50%) even if to a lesser extent than previously
described (Das and Sahoo, 2011). The repeated centrifugations required to purify the samples especially
from both PVA and the reagents used during the Ab-coupling reaction justify the loss of drug from NPs.
(1) Das M., Sahoo S.K., Acta Biomaterialia 7 (2011) 355–369
(2) Fessi H., Puisieux F., Devissaguet J.P., Ammoury N., Benita S., Int. J. Pharm. 55 (1989) R1-R4
(3) Rosca I.D., Watari F., Uo M., J. Control. Release 99 (2004) 271–280.
(4) Grabrucker A. M., Garner C. C., Boeckers T. M., Bondioli L., Ruozi B., Forni F., Vandelli M. A., Tosi G., PLoS ONE 6
(2011) e17851
(5)Liu Y., Li K., Liu B., Feng S. S., Biomaterials 31 (2010) 9145-9155
35
P 19
THE 5-HT3 RECEPTOR HETEROGENEITY: A COMPUTATIONAL STUDY
Marta Del Cadiaa, Francesca De Rienzoa, Maria Cristina Menziania*
a
Dipartimento di Scienze Chimiche e Geologiche, Università degli Studi di Modena e Reggio Emilia, Via
Campi 183, 41100 Modena, Italy.
[email protected]
5-hydroxytryptamine type-3 receptor (5-HT3), an important target of many neuroactive drugs,1 is a cation
selective transmembrane pentamer whose functional stoichiometries and subunit arrangements are still
debated,2,3 due to the extreme complexity of the system. Five different 5-HT3 receptor subunits, 5-HT3A
to E, have been identified. Only subunit 5-HT3A is capable of forming functional homopentameric
receptors, while all the other subunits are apparently functional only if coexpressed with 5-HT3A.4 The
3D structure of any of the 5-HT3R subunits has been solved so
far, and most of the available structural and functional data are
related to the extracellular ligand-binding domain,5-8 whereas the
transmembrane and the intracellular receptor domains are far less
characterised, although they are known to be crucial for receptor
function. Here, for the first time to our knowledge, 3D homology
models for the transmembrane and the intracellular receptor
domains of all the known human 5-HT3 subunits are built and
into
Figure 1- Homology models of the five 5- assembled
HT3R subunit: A, B, C, D and E.
homopentameric (5HT3AR, 5-HT3BR, 5HT3CR, 5-HT3DR and 5-HT3ER) and heteropentameric (5HT3AB, 5-HT3AC, 5-HT3AD and 5-HT3AE) receptors, on the
basis of the known three-dimensional structures of the
nicotinic-acetylcholine receptor9 and of the ligand gated
Figure 2- Electrostatic properties of the
channel from Erwinia chrysanthemi.10 The comparative homomeric 5-HT3AR (side, top and bottom
analyses of sequences, modelled structures and computed view). MEPs isocontour levels are shown at +1
electrostatic properties of the single subunits and of the kT/e (blue) and −1 kT/e (red).
assembled pentamers shed new light both on the
stoichiometric composition and on the physico-chemical requirements of the functional receptors, and
suggest, in particular, that a maximum of two B subunits must be present in the 5-HT3 pentamer for the
channel to be entered and crossed by cations.
References
(1) Peters, J.A., Hales, T.G., & Lambert, J.J. Trends Pharmacol. Sci. 2005, 26, 587-594.
(2) Barrera, N.P., Herbert, P., Henderson, R.M., Martin, I.L., & Edwardson, J.M. PNAS. 2005, 102, 12595-12600.
(3) Lochner, M., & Lummis, S.C.R. Biophys. J. 2010, 98(8), 1494-502.
(4) Holbrook, J.D., Gill, C.H., Zebda, N., Spencer J.P., Leyland, R., Rance, K.H., Trin, H., Balmer, G., Kelly, F.M., Yusaf,
S.P., Courtenay, N., Luck, J., Rhodes, A., Modha, S., Moore, S.E., Sanger, G.J., & Gunthorpe, M.J. J. Neurochem. 2009, 108,
384-396.
(5) Barnes, N.M., Hales, T.G., Lummis, S.C.R., & Peters, J.A. Neuropharm. 2009, 56, 273-284; and references therein.
(6) Moura Barbosa, A.J., De Rienzo, F., Ramos, M.J., & Menziani, M.C. Eur. J. Med. Chem. 2010, 45(11), 4746-60.
(7) Cappelli, A., Manini, M., Paolino, M., Gallelli, A., Anzini, M., Mennuni, L., Del Cadia, M., De Rienzo, F., Menziani, M.
C., & Vomero, S. ACS Med. Chem. Lett. 2011, 2(8), 571–576.
(8) De Rienzo, F., Moura Barbosa, A.J., Perez, M.A.S., Fernandes, P.A., Ramos, M.J., & Menziani, M.C. J. Biomol. Struct.
Dyn. 2012, 30 (3), 280–298.
(9) Unwin, N. J. Mol.Biol. 2005, 346, 967-989.
(10) Hilf, R.J.C., & Dutzler, R. Nature 2008, 452, 375-380.
36
P 20
ENANTIOSELECTIVE SYNTHESIS OF THE NON PROTEINOGENIC
AMINOACID 2,4-DIAMINO-3,3-DIMETHYL BUTYRIC ACID (Ddb)
Luisa Del Zoppo, Erika Marzola, Remo Guerrini, Alberto Cavazzini, Claudio Trapella and Severo
Salvadori
Department of Chemistry and Pharmaceutical Science, University of Ferrara, Italy, via Fossato di Mortara
17/19, 44121
[email protected]
Non natural amino acids are useful molecules to investigate the structure activity relationship of
biologically active peptides and their targets. Our research group contributed to the medicinal chemistry
of neuropeptide S (NPS), a 20-mer peptide able to stimulate arousal and evoke anxiolytic like effects.
Such studies identified position 5 of NPS as crucial for the activation of the NPS receptor (NPSR) and
indicated the D chirality associated to a bulky aliphatic side chain essential requirements for obtaining
high potency antagonism1. In addition, recent findings indicated a basic amino acid tolerated in position 5.
Thus, we decided to synthesise the non natural amino acid Ddb and replace it in position 5 of NPS. In
scheme 1 is depicted the retrosynthetic analysis of Ddb ortogonally protected using the organocatalytical
approach.
NHBoc
NHBoc
FmocHN
COOH
Cbz
H
N
N
Cbz
1
COOH
2
Cbz
H
N
N
Cbz
3
NO2
NO2
COOH
CHO
COOEt
4
5
The ortogonally protected aminoacid 1 could be obtained from compound 2 by hydrogenation and Fmoc
protection. Compound 2 could be obtained from compound 3 by reduction of nitro group and Boc
protection of the corresponding amine. Compound 3 could be obtained from the aldehyde 4 by proline
catalysed alpha amination 2 ; the nitro aldehyde 4 could be simply obtained by Michael addiction of
nitromethane with commercially available ester 5.
The synthesis of compound 3 was achieved in good yield and in both enantiomeric forms using D-Pro
and L-Pro as a catalyst in the alpha amination reaction. Chiral HPLC using Lux 1 column and NMR
spectra confirmed the purity of the final amino acid (figure1).
D-Ddb was then used for the solid phase synthesis of [D-Ddb] 5NPS. Analytical HPLC and mass spectra
analyses confirmed the purity of the desired peptide.
L-Pro catalyst
D-Pro catalyst
Figure 1
1) Guerrini R., Salvadori S., Rizzi A., Regoli D., Calò G.; Med Res Rev; 2010; 5, 751-777.
2) Bogevig A., Juhl K., Kumaragurubaran N.,. Zhuang W, Jorgensen K.A.; Angewandte Chemie, 2002, 41, 10, 1790-1793.
37
P 21
Design and synthesis of new thieno(bis)imide-based n-type and ambipolar
semiconductors
1
1
Margherita Durso, 1Laura Favaretto, 1Massimo Zambianchi, 2Cristian Bettini, 2Pasquale Olivelli,
1
Manuela Melucci
Istituto per la Sintesi Organica e la Fotoreattività (ISOF-CNR), via P. Gobetti, 101, 40129 Bologna
2
MIST.ER Laboratory, via P. Gobetti 101, 40129 Bologna
[email protected]
Organic field effect transistors (OFETs) based on ʌ-conjugated molecular materials attract great attention
because of many advantages in contrast to conventional silicon-based transistors, for instance, low
fabrication cost, large-area manufacturing, and flexibility.
Among molecular materials, oligothiophenes are widely investigated for their chemical versatility and
functionality as p-type semiconductors. (1) On the contrary, thiophene- based materials featuring electrons
(2-3)
and ambipolar charge transport have been more rarely documented.
In this communication, we describe the synthesis of a class of molecular semiconductors bearing the
newly developed thiophene(bis)imide (TBI) as oligomer end moiety, (4) through a direct arylation based
synthetic methodology (5) and demonstrate that the TBI moiety promotes ambipolar or n-type charge
transport depending on the type of the inner ʌ-conjugated core.
Tin/Boron free
synthesis
O
N Bu
S
O
Figure 1. From the synthesis of the organic semiconductor to the OFET device.
(1) Wang, C.; Dong, H.; Hu, W.; Liu, Y.; Zhu, D. Chem. Rev. 2012, 112, 2208;
(2) a) Usta, H.; Facchetti, A.; Marks, T. J. Acc. Chem. Res. 2011, 44, 501; b) Arias, A. C.; MacKenzie, J. D.; McCulloch, I.;
Rivnay, J.; Salleo, A. Chem. Rev. 2010, 110, 3; c) Mishra, A.; Ma, C.-Q.; Baüerle, P. Chem. Rev., 2009, 109, 1141.
(3) Usta, H.; Newman, C.; Chen, Z.; Facchetti, A. Adv. Mater. 2012, 24, 3678.
(4) Durso, M.; Gentili, D.; Bettini, C.; Zanelli, A.; Cavallini, M.; De Angelis, F.; Lobello, M. G.; Biondo, V.; Muccini, M.;
Capelli, R.; Melucci, M. Chem. Commun., 2012, DOI:10.1039/c2cc37053k.
(5) Schipper, D. J.; Fagnou, K. Chem. Mater. 2011, 23, 1594.
38
P 22
1
New Benzo[b]thiophene derivatives as inhibitors of AmpC-β-lactamases
Davide S. F. Farina, 1Alberto Venturelli, 1Puneet Saxena, 2Brian K. Shoichet, 1Maria Paola Costi.
1
Department of Pharmaceutical Sciences, University of Studies of Modena and Reggio,
Via Campi 183, 41124, Modena, Italy
2
Department of Pharmaceutical Chemistry, University of California,
1700 4th Street, MC 2550, San Francisco, CA 94158
[email protected]
The onset of Gram-negative bacterial resistance to β-lactam antibiotics is a major threat to public health
(1). The ability of β-Lactamases enzymes to hydrolyze and deactivate the β-lactam antibiotics (for e.g
penicillins and cephalosporins), impart them a counteracting mechanism against the antibiotics. Of
particular clinical relevance are the chromosomally encoded class C β-lactamases that are expressed by
some enterobacteria and pseudomonas. The broad activity of these enzymes against the regulatory
response to classic β-lactams and the absence of any response from the treatment with classical inhibitors
of beta-lactamases (as clavulanic acid), has motivated this research of novel inhibitors structurally
unrelated to β-lactams. Among those, benzo[b]thiophene-2-ylboronic acid (Fig. 2, 1) (2) is a 27 nM
inhibitor of AmpC-β-lactamase and potentiates the activity of β-lactam antibiotics in bacteria that express
this and related enzymes.
Our aim is to combine chemical structural features that are responsible for enhancing the permeability as
well as the enzyme binding affinity.
Figure 1: AmpC-β-lactamases active site with 7-aminobenzo[b]thiophene-2-ylboronic acid
A new series of derivatives of compound 1 were designed and the synthesis of them is currently ongoing.
Among those, the activity of 7-aminobenzo[b]thiophene-2-ylboronic acid (Fig 2, 2), which bears an amino
group was investigated.(Fig. 1). Moreover, a new series of derivatives which combine the substitution on
position 5 and 3 on benzo[b]thiophene (Fig 2, 3) ring was designed and synthesized with an intention to
evaluate the effect of the double substitution on the factors such as bioavailability and inhibition potency
of the compounds. The results from the preliminary biologic activity evaluation of the synthesized
compounds confirmed our proposed idea regarding the changes on benzo[b]thiophene scaffolds. The final
evaluation is ongoing.
OH
OH
B
OH
B
S
OH
S
R2
R1
OH
B
S
OH
NH2
1
2
3
Figure 2:benzo[b]thiophen-2-yl-boronic acid (1), 7-amino benzo[B]thiophene-2-ylboronic acid (2), Scaffold new library (3)
References:
1. Perez-Llarena, F. J.; Bou, G.. Curr. Med. Chem., 2009, 16, 3740.3765
2. Weston, G. S., Blazquez, J., Baquero, F., Shoichet, B. K.; J. Med. Chem., 1998, 41, 4577-4586
Acknowledgments:
I thank the NIH Grant GM63815 (to Brian Shoichet, subcontract to University of Modena and Reggio Emilia).
39
P 23
Divalent cations modulate membrane binding and pore formation of a potent
antibiotic peptide analog of Alamethicin
Fasoli A., Benedusi M., Aquila M, and Rispoli G.
Dipartimento di Scienze della Vita e Biotecnologie, Università degli Studi di Ferrara.
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8
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40
P 24
Chemical information on carboxylic acid bi-molecules from Fourier transform
microwave spectroscopy
Gang Feng,1 Qian Gou,1 Luca Evangelisti,1 Laura B. Favero,2 Assimo Maris1, Annalisa Vigorito,1 Walther
Caminati1, Rolf Meyer3 and Zhining Xia4
1
2
Department of Chemistry, University of Bologna, Via Selmi 2, I-40126 Bologna, Italy. [email protected]
Istituto per lo Studio dei Materiali Nanostrutturati (ISMN, Sezione di Bologna), CNR, Via Gobetti 101, I-40129
3
Sonnenbergstrasse 18, CH-5621 Zufikon, Switzerland
4
Chemistry and Chemistry Engineering College, Chongqing University, Chongqing, 400030, P. R. China
Carboxylic acid trends to exist as dimers, forming an eight-membered ring which contains two
strong OH«O hydrogen bond (HB). This kind of bi-molecule represents prototype model system for
studying the HB and the double proton transfer. We studied several carboxylic acid bi-molecules in gas
phase by using FTMW spectroscopy combined with theoretical calculations.
In these carboxylic acid bi-molecules, the double proton transfer can easily take place, connecting
either two equivalent, or two non-equivalent molecular configurations. In the first case, we studied the
dimer of acrylic acid (AA),(1) which can exist in two forms, as shown in Figure 1. The
cis«trans/trans«cis form has a permanent value of the ȝb dipole moment component, which allowed
measuring its pulsed jet Fourier transform microwave (MW) spectrum. From the tunneling splitting, we
could determine the barrier to the proton transfer to be 2485(150) cm-1. In the second case, we studied the
confromational equilibrium in acrylic acid (AA)«formic acid (FA) bi-molecule.(2) Two configurations, cis
and trans, of AA«FA have been assigned (Figure 2). The measurements have been extended to four
deuterated and to four 13C (natural abundance) species, and their combinations, for each conformer. These
data allowed to determine the carbon skeleton structures and to size quantitatively the structural effect
caused by the OHĺ2D isotopic substitutions (Ubbelohde effect).
cis···cis
cis···trans
mo
mo
trans···trans
trans···cis
Figure 1. Homo-conformational dimers of AA (s-cis˜˜˜s-cis, s-trans˜˜˜s-trans) are non-polar. While the hetero-conformational
dimers (s-cis˜˜˜s-trans, s-trans˜˜˜s-cis) are polar molecules, which are two equivalent conformations connected with the double
transfer.
cis
mo
trans
«
Figure 2. Two different configurations, cis and trans, of AA FA were connected with doulbe proton transfer.
(1) Feng, G.; Favero, L. B.; Maris, A.; Vigorito, A.; Caminati W.; Meyer, R. J. Am. Chem. Soc., 2012, 134, 19281í19286.
(2) Feng, G.; Gou, Q.; Evangelisti, L.; Xia, Z.; Caminati W. Manuscript submitted.
41
P 25
Nanotechnology Control of Self Organized Biomolecules and Biomaterials for
Medical Research
1
1
G. Foschi, 1E. Bystrenova, 1F. Valle, 1B. Chelli, 1S. Casalini, 1T. Cramer, 1M. Barbalinardo, 1F.
Leonardi, 1A.Campana, 2P. Greco and 1F. Biscarini
Consiglio Nazionale delle Ricerche - Istituto per lo Studio dei Materiali Nanostrutturati (CNR-ISMN),
Via Gobetti 101, 40129 Bologna, Italy
2
Scriba Nanotecnologie srl, Via P. Gobetti 53/2, 40129 Bologna, Italy
[email protected]
In the last decade, nanotechnology has experienced an ever-growing improvement in the design of novel
materials and their control. In the life science domain, nanotechnology is a versatile approach in order to
develop new tools for nanomedicine, including scaffolds for tissue engineering, stem cell-based therapies,
biosensors and implantable devices. Soft lithography(1) and microfluidic systems offer an useful toolbox
both to study biomolecules/biomaterials under confined environments and to fabricate new topographic
features onto the substrates of interest. As a result, these techniques allow us to study the interplay
between mechanics and chemistry.
Here, we present new patterns of biomolecules, such as ȕ-amyloid (Aȕ) and amphiphilic cyclodextrin
(ACyD) functionalized with fouling and antifouling cues by means of soft-lithographic technique termed
MicroMolding in Capillaries (MIMICs)(2). In the former case, we have studied the early stages of Aȕ1-40
peptide aggregation at the solid-liquid interface induced by the confinement. Furthermore it has been
pointed out the role of the surface tension, which affects the size and the morphology of the final
aggregates. In the latter case, we fabricate patterns of ACyD gradients onto a glass substrate, aiming at
the study of motility, adhesion, functionality and differentiation of cells exposed to external stimuli.
Our approach takes advantage of a
single-step
fabrication
yielding
substrates with micro- and nanometer
features. This approach allows us to
study the main properties of the
biomolecules confined at a scale
level comparable to the physiological
environment.
In addition, we have fabricated and Figure 1 Atomic force microscopy images (5XȝP show Figure 2 Atomic force
the evolution of the morphology of the aggregates changing microscopy image of AcyD
characterized
a
poly(lactic-co- the surface tension of the confinement.
patterned on a glass sustrate.
glycolic acid) (PLGA) scaffold,
which is biocompatible and biodegradable, by means of a solvent casting technique. These PLGA-based
scaffolds have been used to assess the biocompatibility of the stem cells, namely adhesion and
differentiation. As a consequence, this PLGA scaffold will be integrated in a implantable organic device
targeted to Spinal Cord Injury. The PLGA scaffold treated with stem cells can satisfy the stringent
requirements of such device.
In conclusion, this work highlights how to exploit nanotech techniques, such as MIMIC and μfabrication, for WKH FRQWURO RI ELRPROHFXOHV $ȕ $&\' DQGRU ELRPDWHULDOV 3/*$ DLPLQJ DW
biomedical applications.
Figure 3 (a) Optical micrograph showing the
morphology of a thin PLGA film prepared at
37°C (Inset: PLGA transparent film
photograph); (b) AFM image of the PLGA
film (the inset is the corresponding water
contact angle measurement); (c) SEM image
of neural progenitor stem cells on PLGA film.
(1) Xia, Y.; Whitesides, G.M. Angew. Chem. Int. Ed. 1998, 37, 550-575.
(2) Cavallini, M.; Albonetti, C.; Biscarini, F. Adv. Mater. 2009, 21, 1043-1053.
42
P 26
Study of cosmetic and pharmaceutical compounds: preparation and usage
of analytical instrumental techniques
1
1
Giada Freguglia
University of Modena and Reggio Emilia, 183 Campi street, 41125 Modena
[email protected]
The study concerning pharmaceutical and cosmetic compounds has been focused on two contexts: an
analytical pharmaceutical study and a spectroscopy study of ancient cosmetic remains collected from
national museums and application of SERS technique, this is an innovative technique in Raman analysis,
that reduce the fluorescence effects due to organic compounds and it is applied in different
pharmaceutical, biochemistry and forensics fields (1).
The pharmaceutical context regarded the study of polymorphic compounds, in particular the study and
characterization of active pharmaceutical compounds (API) such as ampicillin. From literature ampicillin,
α-aminobenzylpenicillin or 6-[D (-)-α aminophenylacetamido] penicillanic acid, exist such as trihydrate,
monohydrate and two anhydrous forms (2-4), in laboratory, the polymorphic forms of ampicillin were
prepared following several crystallization methods. For characterizing pharmaceutical compounds
different techniques have been used: FT-IR technique, differential scanning calorimetry (DSC), TGA and
X-Ray powder diffraction (5). For the first time the polymorphic forms of ampicillin were studied by
Raman and hot-stage Raman (HSM) microscopy, (6) and with the SERS (Surface Enhancement Raman
Spectroscopy) technique, using a silver colloidal solution prepared following the Lee and Meisel method
(7). The experimental picks assignments were assisting with quantum mechanical calculations.
Regarding the cosmetic field, the study is concerned ancient eye-drops collected from Atestino Museum
(Este). Nowadays this compounds class is not so studied (8). The analysis showed samples of being
mostly composed by “calamine”, a mixture of silicates and carbonates, copper compounds as tenorite and
cuprite, and in addition sulphides, in particular pyrite, with antibacterial properties. From literature these
compounds were mixed together with organic matrices, wine, milk, vinegar or eggs white and then put on
the affected eye.
(1) Bonner J., Surface Enhanced Raman Spectroscopy (SERS), November 26, 2007
(2) Shefter E. et al., J. Pharm. Sci., 62/5, 791, 1973.
(3) James M.N.J. et al. Nature, 220 168, 1968.
(4) Ivashkiv E., In: Analytical Profiles of Drug Substances, vol. 2., Academic Press, New York, K. Florey, (Ed.), 1973.
(5) Gamberini M.C., Baraldi C., Tinti A., Palazzoli F., Ferioli V., J. of Molecular Structure, 840, 29–37, 2007.
(6) Gamberini M.C, Baraldi C., Tinti A., Rustichelli C., Ferioli V., Gamberini G., J. of Molecular Structure; Vol 785/1-3, 216224, 2006.
(7) Lee P.C., Meisel D., J. Phys. Chem., 86, 3391, 1982.
(8) Boyer R. et al., Instrument et collyres d’un oculiste, Gallia, Tome 47, 235-243, 1990.
43
P 27
Diversity-Oriented Synthesis of Macrocyclic Peptidomimetics
1
1
Elisa Giacomini, 2Kathy Hadje Georgiou, 2Albert Isidro-Llobet, 2David Spring.
Department of Pharmacy and Biotechnologies, University of Bologna, via Belmeloro 6, 40126 Bologna,
Italy.
2
Department of Chemistry, University of Cambridge, Lensfield Road, CB2 1EW, UK.
[email protected]
Diversity-oriented synthesis (DOS) is a tool used for the efficient generation of chemical libraries
containing structurally diverse and complex small organic molecules, which represent an important
source of biologically active agents. In a DOS approach, simple and similar starting materials are
converted into a collection of complex and diverse small molecules through few synthetic steps (1): a
forward-synthetic analysis reveals that the key to creating structural diversity is inventing branching
synthetic pathways, while the structural complexity can be achieved using intramolecular reactions,
cycloadditions, and multicomponent reactions.
We report here the synthesis of a DOS library of diverse small molecules based around a common
macrocyclic peptidomimetic framework, containing structural motifs present in many naturally occurring
bioactive compounds (2). This library has two main general structures: both of them have a triazole ring
as bioisoster of the amide bond, and one of them incorporates a diketopiperazine (Figure 1).
The synthetic strategy was based around the elegant three-phase approach described by Nielsen and
Schreiber (3), called Build/Couple/Pair:
1)
Build phase: asymmetric syntheses of chiral building blocks (BB) with functional groups essential
in the further steps.
In this step we synthesized two kind of simple amino acids as BB: azido-amines and alkyne-acids.
2)
Couple phase: intermolecular reactions to join BB; this process provided the basis for
stereochemical diversity.
Couplings via amide bond between the azido-amines and alkyne-acids were performed to obtain linear
peptidomimetics.
3)
Pair phase: intramolecular reactions in order to provide scaffold diversity.
This phase comprised two cyclization steps to generate first the desired macrocycles with triazole ring,
then the diketopiperazine motif was introduced into the framework.
All the compounds are currently tested against a number of targets including different bacteria types and
cancer cells.
Figure 1: general structures of the library compounds.
(1) Galloway, W.; Isidro-Llobet, A.; Spring, D.; Nat. Commun., 2010, doi: 10.1038/ncomms1081.
(2) Isidro-Llobet, A.; et al; Proc Natl Acad Sci U S A., 2011, 17, 6793-8.
(3) Nielsen, T.; Schreiber, S.; Angew. Chem., Int. Edit, 2008, 47, 48±56.
44
P 28
HONEY ADULTERATION DETECTION METHOD BASED ON
PROTEINS EXTRACTION AND IDENTIFICATION
Graziosi Riccardo(1), Papotti Giulia(1) and Bertelli Davide(1)
(1)
Department of Pharmaceutical Sciences, University of Modena and Reggio Emilia, via Campi 183 Modena, Italy
[email protected]
Honey is a nutritious and healthy natural food produced by honey bees from plant nectars: it
consists mostly of the sugars glucose and fructose, as well as maltose, sucrose, water, pollen and
other minor components (1). Food authentication is an international issue in quality control and
food safety. Regulatory authorities, food processors, retailers, and consumers are interested in
knowing the origin and quality of foods; for these reasons the deliberate mislabeling and
adulteration of foods, particularly honeys, are matters of increasing global concern. Many studies
have reported on the chemical constituents of honey such as sugars and flavonoids (2), and the
analysis of many of those components is applicable to adulteration detection. Another approach is
based on analysis of the composition or origin of proteins in honey: this natural product contains
many different proteins in minute quantities and several enzymes, such as amylase, α-glucosidase,
β-glucosidase and glucose oxidase. Since they originate from Apis mellifera, the identification of a
protein or an enzyme of a different origin could be interpreted as a proof of adulteration. We have
focused on the detection of an α-amylase from Aspergillus niger, an enzyme that can be employed
to produce glucose syrup, used for honey adulteration. This enzyme was added to honey samples in
different concentration, ranging from 0,1 to 1 nmol/ml, and different isolation and analysis
techniques were tested. Honey samples were dialyzed against ultrapure water for 3 days using a
cellulose membrane with a 12KDa cutoff, then lyophilized to concentrate the residue protein.
Passivation of the membrane to avoid loss of protein during the dialysis was also tested, but no
significative difference was found after determination with Bradford assay. A separation using
disposable C18 SPE column was also tested. Samples obtained after isolation were analyzed using
both MALDI-TOF MS and HPLC CHIP Q-TOF MS. The sensitivity of MALDI-TOF resulted
much lower than the one achieved with HPLC-MS, which was able to detect concentration as low
as 0.1 nmol/ml for dialyzed samples. The separation obtained with the SPE columns was not
satisfactory, probably because amylase was strongly bound to the C18 column and elution was not
efficient.
[1] Tewari, J.; Irudayaraj, J. 2004. Quantification of saccharides in multiplefloral honeys using Fourier transform
infrared microattenuated total reflectance spectroscopy. J. Agric. Food Chem., 52, 3237–3243.
[2] Merker, H. M., & Beecher, G. R. 2000. Measurement of food flavonoids by high performance liquid
chromatography: A review. Journal of Agricultural and Food Chemistry, 48, 577–599.
45
P 29
$QHZFODVVRIȕ-turn mimics for studying protein-protein interactions
1
1
A. Greco, 1R. De Marco, 1A. Tolomelli, 1S. Tani, 1F. Ferrero, 1L. Gentilucci
'HSDUWPHQWRI&KHPLVWU\³*&LDPLFLDQ´8QLYHUVLW\RI%RORJQD9LD6HOPL%RORJQD,WDO\
[email protected]
Protein-protein interactions (PPI) are central to biology and constitute one mechanism by which genomic
information is translated into a regulated biological response. Proteins exercise a variety of functions in
living organisms. They act as neurotransmitters, neuromodulators, hormones, paracrine factors, cytokines
and antigens, and influence essentially all vital physiological processes.(1) Peptides are generally poor
drug candidates due to their limitations, characterized by fast hydrolytic cleavage, poor penetration of
membranes, rapid photolytic degradation, conformational instability and unfavorable pharmacokinetics.
Numerous methods have been examined to overcome these problems and to improve the bioavailability
of native and synthetic proteins, but these have met with only limited success.(2) For these reasons, much
effort has been expended to find ways to replace portions of biologically active peptides with non-peptide
structures, with the aim of obtaining orally bioavailable entities. Such compounds containing non-peptidic
structural elements that are capable of mimicking or antagonizing the biological action of a natural parent
peptide are defined as peptidomimetics. The scope of research in this field has expanded rapidly and
represents today an important approach in peptide chemistry and drug discovery.(3)
Peptides normally exist in solution as an equilibrium mixture of conformers. One approach to obtaining
peptidomimetics is to incorporate conformationally restricted amino acid units or impose other
conformational constraints. Therefore, by affixing or incorporating templates that fix secondary or tertiary
structures of small peptides, a medicinal chemist can create synthetic molecules that mimic localized
elements of proteins.(4)
The ȕ-turn is thus an attractive motif for intervention by low
molecular weight, conformationally constrained peptidomimetic
scaffolds. The ȕ-turn occurs where the polypeptide backbone
reverses direction, and consists of four amino acid residues i to i+3 in
which the distance between CDi and CDi+3 is about 7 Å; depending
on the dihedral angles I and M of the residues i+1 and i+2, the turns
are classified in different types. Thus, as part of a program directed
towards the modulation of selected PPI, we set out to develop a
straightforward procedure for constraining the conformation of a
peptide lacking of a pre-formed scaffold and for obtaining a new
FODVVRIȕ-turn mimetics.
Among the potential applications in medicinal chemistry, we utilized
these peptidomimetics for the design of constrained analogues of the opioid peptides endomorphins and
for the study of active conformation of endomorfine-1. Moreover, we exploited the new scaffold obtained
for the preparation of anti-inflammatory integrin inhibitors, or of analogues of the antibiotic Linezolid.
(1)Bonner, G.G.; Davis, P.; Stropova, C. Peptides, 1997, 18, 93.
(2) Szymkowski D.E. Drug Discov. Today, 2004, 9, 381.
(3) Gante, J. Angew. Chem. Int. Ed. Engl., 1994, 33, 1699.
(4) Fairlie, D.P.; West, M.L.; Wong, A.K. Curr. Med. Chem., 1998, 5, 29.
46
P 30
A new modified electrode for OH radical detection
1
1
Domenica Tonelli, 1Isacco Gualandi
Università di Bologna, Dipartimento di Chimica Industriale ³7RVR0RQWDQDUL´, Viale del risorgimento 4,
Bologna, Italy.
[email protected]
Hydroxyl radical, that belongs to the known most reactive chemical species, has an important role in
medicine, depurative processes and in environmental chemistry. The direct OH radical determination in a
lot of matrices is quite difficult, because the presence of scavengers leads to an extremely low steady-state
concentration. The only possibility to detect this species is using a probe which reacts very quickly with
OH radical producing characteristic products that can be easily detected with a lot of analytical techniques
like EPR, HPLC and capillary electrophoresis.
A new electroanalytical approach, based on the attack of OH radicals on modifying electrode films, was
proposed in some papers (1, 2). Herein, a new modified electrode for OH radical indirect detection is
described. A polyphenol modified glassy carbon (GC) electrode was prepared by oxidative potentiostatic
electropolymerization of 0.05 M phenol in 1 M H2SO4. The film having a thickness of ~10 nm perfectly
covered the GC surface and inhibited the charge transfer of many redox species. The degradation of the
polyphenol film, that was induced by OH radical generated by Fenton reaction and by H2O2 photolysis,
was evaluated by cyclic voltammetry (CV) and chronoamperometry using the redox probe Ru(NH3)63+. In
Fig. 1 the effect of electrode modification and OH attack can be seen. On the bare GC the charge transfer
is very fast and the peaks system of the couple Ru(NH3)63+/ Ru(NH3)62+ is well evident. After the
modification of the electrode surface, the charge transfer is very slow and an insulating behavior can be
observed, as indicated by the disappearance of peaks couple. If the modified GC is kept into a solution
where OH radicals are generated by the Fenton reaction, the Ru(NH3)63+/Ru(NH3)62+ peaks are partly
restored. When the OH production increases, i.e. at higher H2O2 concentrations, the uncovered area
proportionally increases, suggesting that this phenomenon can be used to determine the OH radical
concentration. Some kinetic calculations were carried out to fully understand the process that leads to the
analytical signal. The modified electrode works in a concentration range between 10-11 and 10-12 M. The
effect of some interferents was studied. Among the investigated oxidants only the strong ones, like
KMnO4, are able to attack the film. The modified electrode was used to evaluate the performances of
different TiO2-based photocatalysts and to develop a new method to determine the antioxidant capacity.
Figure 1. CVs (scan rate: 50 mV s-1) recorded in 0.5 M buffer acetate (pH = 4.6) containing 5× 10-3 M Ru(NH3)63+ at bare
GC, polyphenol-GC as prepared and after attack by OH radicals (Fenton reaction conditions: t = 5 min, [Fe++] = 5× 10-2 M,
[H2O2] = 0,5 M)
(1) Mello, L.D., Hernadez, S., Marrazza, G., Mascini, M., Kubota, L.T., Biosens. Bioelectron. 2006, 21, 1374-1382.
(2) Scholtz, F., Lopez de Lara Gonzàlez, G., Machado de Carvalho, L., Hingelmann, M., Brainina, K.Z., Kahrlet, H., Smail
Jack, R., Troug Minh, D., Angew. Chem. Int. Ed. 2007, 46, 8079-8081.
47
P 31
Unprecedented Bisphosphine-1,2,3-Triazolylidene based Pt(II) complexes:
photophysical characterization
a
a
Maria Pia Gullo, bMark Gandelman and aAndrea Barbieri.
Istituto per la Sintesi Organica e la Fotoreattività (ISOF), Consiglio Nazionale delle Ricerche (CNR), Via
Gobetti 101, 40129 Bologna, Italy
b
Schulich Faculty of Chemistry, Technion-Israel Institute of Technology, Haifa, 32000
[email protected]
Recently, it was reported the preparation of a new class of pincer ligands utilizing a highly modifiable
triazole unit as central core motif (Fig. 1a). (1) These systems are interesting because of their possible
applications in several fields: coordination, mechanistic, synthetic and supramolecular chemistry, in
nanoscience and in the development of sensors and molecular switches. (2) Most significantly, they offer
opportunities to tune the steric and electronic properties of metal atoms, generating extensive research into
the use of the derived complexes as catalysts, in particular, if they are bonded to late-transition metals.
1a
N
3a
2a
N
N
N
N
N
PPh2
PPh2
Ph2P
PPh2
N
Na+
N
N
Ph2P
PPh2
(a)
1
N
N
N
N
Ph2P
Pt
Cl
3
2
N
N
Ph2P
Cl
N
N
Ph2P
PPh2
N
PPh2
Pt
Pt2+
Ph2P
PPh2
PPh2
Cl
N
(b)
N
N
Fig. 1. Structures of (a) triazolyl-based pincer ligands 1a, 2a, 3a and (b) Pt-triazolylidene complexes, 1, 2, 3.
The present communication is focused just on these triazole-based ligands and their complexes with
Pt(II) (Fig. 1b, 1, 2, 3), prepared for the first time by Gandelman et al. (1) and investigated by us in order to
achieve information about their photoluminescence properties.
Complex 1 is obtained with a tridentate (involving carbon 5 atom of triazole) coordination mode, using
a 1,4-substituted triazole, prepared by click chemistry, widely used for molecular assembly; complexes 2 and
3 contain the complementary isomers, the 4,5-substituted triazoles, practically unemployed before now for
building functional compounds. In both the cases, the substituents on the triazole core are phosphine groups
that work as coordinating atoms to the metal centre. Furthermore, in these ligands, the triazole scaffold is
neutral (1a, 2a) or negatively charged (3a).
48
Fig. 2. Emission spectra of both ligands, 1a, 2a, 3a, and complexes, 1, 2, 3 in CH2Cl2:MeOH 1:1 v/v solution
at 77K.
Emission from this class of compounds in solution has, typically, quantum efficiencies significantly
lower than octahedral d6 metal complexes such as Ru(II) polypyridine complexes. This effect is attributed to
enhancement of the rates of non-radiative decay pathways involving solvent interaction with the open
coordination sites of the square planar geometry. Usually, only Pt(II) complexes containing ligands with
strong field effect, destabilizing the MC centred excited states responsible for the non-radiative deactivation
of the MLCT emitting state, display OXPLQHVFHQFH 7KDW¶V ZKy just few Pt(II)-phosphine (a weak field
ligand) complexes have been reported to be emissive and in most cases the phosphine ligands work only as
spectator, not being directly involved in emission process. (6) In other cases the luminescence is associated
with metal-metal interactions in binuclear Pt(II) complexes. (7)
Just one example of emission directly related to the phosphine ligand is reported in literature (4) and is
observed in solid state at room temperature for systems in which phosphine group is inserted into an aromatic
system. The Pt(II) complexes presented in this communication show a similar behaviour, thanks to the
aromatic or highly conjugate triazole scaffold, working as luminophore. This type of structure allows the
observation of an emission in glassy matrix from an excited state of 3MLCT nature, formed by intersystem
crossing (3). In addiction to this effect, in complex 1, the introduction of the strong electron-donating
carbine-type ligand, produces the enhancement of luminescence properties, not only by destabilization of the
non-emissive d±d LF state, as a result of the enlargement of d±d orbital splitting by such strong field ligand,
but also by stabilization of the emissive excited state of 3MLCT/3LLCT character. (5)
In conclusion, this study opens the door to the design of new class of triazole derivative Pt(II)
complexes, with improved luminescent properties, in order to extend their application in electroluminescence
devices.
(1) [a] Schuster, E.M.; Botoshansky, M. and Gandelman, M. Dalton Trans. 2011, 40, 8764±8767; [b] Slutsky Smith, E.; Molev, G.;
Botoshansky, M. and Gandelman, M. Chem. Commun. 2011, 47, 319±321.
(2) [a] van Koten, G.; Albrecht, M. Angew. Chem. 2001, 113, 3866; [b] van der Boom, M. E.; Milstein, D. Chem. Rev. 2003, 103,
1759.
(3) [a] Cheung, T.C.; Cheung, K.K.; Peng, S.M.; Che, J. Chem. Soc. Dalton Trans. 1996, 1645;䯠
Cheung, T.C. ; Peng, S.M.; Che, C.M. Inorg. Chem. 1999, 38, 4046.
[b] Lai, S.W.; Chan, M.C.W.;
(4) Pawlowski, V.; Kunkely, H.; Lennartz, C.; Böhn, K. and Vogler, A. Eur. J. Inorg. Chem. 2004, 4242-4246.
(5) Wing-Wah Yam, V. and Man-Chung Wong, K. Chem. Commun. 2011, 47, 11579±11592.
49
(6) [a] Wing-Wah Yam, V. and Man-Chung Wong, K. Chem. Commun. 2011, 47, 11579±11592; [b] Yam, W.W.; Yeung, P.K.Y.;
Cheung, K.K. J. Chem. Soc., Dalton Trans. 1994, 2587; [c] Bevilacqua, J. M.; Zuleta, J.A.; Eisenberg, R. Inorg. Chem. 1994, 33,
258; [c] DePriest, J.; Zheng, J.Y.; Goswami, N.; Eichhorn, D.M.; Woods, C.; Rillema, D.P. Inorg. Chem. 2000, 39, 1955.
(7) [a] Che, C.M.; Yam, V.W.W.; Wong, W.T.; Lai, T.F. Inorg. Chem. 1989, 28, 2908; [b] Xia, B.H.; Che, C.M.; Phillips, D.L.;
Leung, K.H.; Cheung, K.K. Inorg. Chem. 2002, 41, 3866.
50
P 32
Determination of Neurosteroid levels in rat brain
1
1
Mojgan Heidari, 2Cecilia Rustichelli,
Università degli Studi di Modena e Reggio Emilia (Scuola di Dottorato di Scienze e Tecnologie dei
Prodotti per la Salute)
[email protected]
2
Università degli Studi di Modena e Reggio Emilia
The steroids synthesized by the brain and nervous system are called neurosteroids; they are synthesized in the central and
peripheral nervous system, especially in myelinating glial cells, from cholesterol or steroidal precursors imported from
peripheral sources.
Neurosteroids accumulate in the brain after local synthesis or after metabolism of adrenal steroids or gonadal steroids,
especially testosterone. They include 3β-hydroxy-Δ5 derivatives, such as pregnenolone (PREG) and dehydroepiandrosterone
(DHEA), their sulfates, and reduced metabolites such as the tetrahydro derivative of progesterone 3α-hydroxy-5α-pregnane-20one (Allopregnanolone).
These compounds act as allosteric modulators of neurotransmitter receptors, such as GABAA, NMDA and sigma receptors and
they regulate the function of neuronal circuits by acting as modulators of excitatory and inhibitory synaptic transmission.
These actions of neuroactive steroids are relevant for the normal function of the nervous system and it is well known that their
levels can be altered in neurodegenerative disorders.
Allopregnanolone (AP) is a potent positive endogenous modulator of GABAA receptors exhibiting anxiolytic and
anticonvulsant activity. AP shows pronounced neuroprotective actions in the setting of excitotoxicity, traumatic brain injury
and neurodegeneration; it also increases myelination, enhances neurogenesis, decreases inflammation and reduces apoptosis.
Allopregnanolone aids neurogenesis and has been found to reverse neuron proliferative deficit and cognitive deficits in mouse
model of Alzheimer’s disease.
In addition to allopregnanolone, other neurosteroids such as dehydroepiandrosterone (DHEA) and pregnenolone sulphate (PS),
have been implicated in a broad range of biological effects in humans and other mammals.
Dehydroepiandrosterone, (DHEA), also known as (3β)-3-hydroxyandrost-5-en-17-one is an important endogenous steroid
hormone exhibiting different effects: anti-diabetic (increases the sensitivity of cells to insulin), anti-dementia, anti-obesity,
anti-carcinogenic, anti-stress (assists in returning the body to a balanced state after a stress reaction), immune-enhancing
(boosts immunity by stimulating killer cell activity), anti-viral and anti-bacterial, anti-aging and anti-heart disease effects,
antioxidant and hormone regulator (it helps regulate the thyroid & pituitary glands, and enhances thymus gland function),
decreases cholesterol, stimulates the production of human growth hormone; improves cognitive function and bone formation
and libido, enhances mood by increasing the brain's serotonin levels.
Pregnenolone, also known as 3α,5β-tetrahydroprogesterone (3α,5β-THP), is an endogenous steroid hormone involved in the
steroidogenesis of progestogens, mineralocorticoids, glucocorticoids, androgens, and estrogens, as well as the neuroactive
steroids. As such it is a prohormone, though it also has biological effects of its own with potent anxiolytic effects.
Pregnenolone and its sulfate ester are under investigation for their potential to improve cognitive and memory functioning.
Pregnenolone is also being considered as a potential treatment for schizophrenia.
Pregnenolone sulfate (PS) is a negative allosteric modulator of the GABAA receptor as well as a positive allosteric modulator
of the NMDA receptor. PS can exhibit a variety of neuropharmacological actions, such as memory and learning enhancement,
convulsant effects and other functions associated with response to stress and mood regulation. The presence of PS in the brain
of mammals is still a matter of controversy; although several studies provided indirect evidence for the presence and biological
activity of 3β-hydroxysteroid sulphates in rodent brain, no PS amount above the detection limit was reported by the papers
present in the literature up till now.
The goal of my project is the development of an analytical protocol for neurosteroid dosage in biological tissues of rats
(cerebral cortex and hippocampus). A SPE extraction procedure was optimized to isolate the compounds of interest from brain
homogenates in order to remove the phospholipid contamination and therefore the problems of ion-suppression and ghost
peaks during the following LC-ESI-MS/MS analyses. The analysis of the extracts was performed by HPLC/MS-QQQ with the
multiple reaction monitoring (MRM) technique, monitoring one parent ion and two transition for each neurosteroids of
interest, in order to ensure a reliable identification.
The sample processing is simple, but enables the efficient extraction of free and sulphate steroids from brain samples. No
derivatization or solvolysis procedure is required prior to LC-MS/MS analysis, which may lead to errors in quantitation of
steroid sulphates.
The developed method was evaluated in terms of linearity, accuracy, precision and extraction efficiency; the use of deuterated
steroids as internal standards, which display stable properties through all the process of analysis, considerably enhances
measurements accuracy. The protocol showed adequate specificity and sensitivity for the analysis of PS and ALLO, despite the
low concentration in brain tissue under physiological conditions. The choice of the SPE phase used in the extract purification
and the optimization of the chromatographic conditions enabled a marked reduction of the matrix effect.
Finally, the developed procedure has been successfully applied to quantify PS, DHEA and AP levels in different brain rat areas
and therefore could be of great interest to study the change in PS, DHEA and AP levels during various neurodegenerative
diseases or after pharmacological/dietetic treatment.
(1) J. Med. Chem. 2002, 12, 6500-6521.
51
P 33
Patterning of silicon surfaces by using electrochemical reaction confined in the nanochannels
1,2
1
Zahra Hemmatian, 1Massimiliano Cavallini
CNR-Institute of Nanostructured Materials (ISMN)-Bologna, Via P. Gobetti 101- 40129 Bologna, Italy,
2
Alma Mater Studiorum, University of Bologna, Via Zamboni, 33 - 40126 Bologna, Italy
[email protected]
Local oxidation or nano-oxidation of metallic, organic and semiconducting films by a conductive probe of
an atomic force microscope (AFM) is emerging as a reliable and versatile method to fabricate nanometerscale structures and devices [1]. Nano-oxidation has been applied to yield patterns made of dots and lines
of controlled size and positions that have been used to demonstrate bit writing with areal densities of
about 1 terabit per squared inch to generate sets of interdigitated lines with a periodicity of 13 nm, to
fabricate sub-micrometer gratings or optical waveguides with subwavelength cross-sections. Local
oxidation nanolithography (LOxL) has also been applied to fabricate several electronic devices with
critical features in the nanometer range such as single electron transistors, superconducting interference
devices or antidot lattices.
In this study, electrochemical LOxL has been upgraded from single electrochemical LOxL to parallel
methods, performing the process using a metalized stamp rather than an AFM tip to fabricate the nano
devices and patterned surfaces [2]. In the optimized conditions by applying a voltage of +30V for 60s in
an high humid chamber, between a metalized PDMS stamp and silicon surfaces, the electrochemical
reaction has confined in the nano-channels only under the protrusions of the stamp, and parallel stripes of
< 200 nm wide and ~10 nm height formed perfectly adapted to the stamp features. By applying more than
once LOxL, the complex structures of electrochemical SiO2 (e-SiO2) in a grid form has been fabricated.
These patterned e-SiO2 substrates as stripes and grid can be used to study the orientation of some organic
materials [3].
Furthermore, the effect of negative bias on parallel electrochemical reaction, which should result in the
electrochemical local reduction of the surface (LR) have been investigated. This operation was performed
by rotating the metalized PDMS stamp for 90° and applying negative bias after LOxL. The obtained
results showed that in this condition patterned e-SiO2 stripes were removed partially as a cross points.
(1) Pliskin W A 1977 J. Vac. Sci. Technol. 14 1064±81.
(2) Cavallini M, Hemmatian Z, Riminucci A, Prezioso M, Morandi V, and Murgia M 2012 Adv. Mater., 24, 1197±
1201.
(3) C. Albonetti et al. 2011 Int. J. Mol. Sci., 12, 5719.
52
P 34
NATURAL PRODUCT-LIKE SMALL MOLECULES AS
CHEMICAL PROBES INTERFERING WITH THE CELL CYCLE
PROGRESSION IN TUMOR CELLS
1
C. Ianni, 1M. Recanatini, 2M. Tolomeo, 1M. Roberti
1
Dipartimento di Scienze Farmaceutiche, Università di Bologna, via Belmeloro 6,
40126 Bologna, Italy .2Centro Interdipartimentale di Ricerca in Oncologia Clinica,
Università di Palermo, Via del Vespro 129, 90127 Palermo, Italy.
[email protected]
In the search for innovative antitumor lead candidates, we implemented a chemical
biological experimental platform to discover new compounds able to interfere with the
cell cycle control mechanisms. In this context, with the aim of enhancing the structural
complexity and diversity of an existing collection of bi- and ter- phenyl compounds, we
synthesized a series of new molecules that are hybrids of spirocyclic ketones as
complexity-bearing cores with bi- and ter-phenyls as privileged fragments 11. These
compounds showed a well-defined activity on apoptosis or differentiation, thus
representing SRWHQWLDO OHDGV IRU QHZ DQWLFDQFHU DJHQWV¶ GHYHORSPHQW DQG DV FKHPLFDO
probes to study signaling networks in neoplastic cells2.
To further explore this class of compounds we designed and synthesized new
derivatives improving the skeletal diversity. The synthetic platform relies on coupling
the well-known domino Knoevenagel/hetero Diels-Alder (K-H-DA) sequence to Suzuki
reaction. The selected domino process carried out in parallel, starting from simple and
readily available substrates, allowed us to generate in one step structurally and
stereochemically complex molecules in highly diastereospecific fashion under
organocatalysis. Further synthetic manipulations of the properly functionalized
molecular skeletons via Pd-catalyzed Suzuki coupling, delivered a collection of new
natural-like biphenyl and terphenyl compounds 2. We are currently combining the
advantage of this synthetic platform with that of microwave assisted technique, in order
to speed up the synthesis and improve the yields of the new derivatives. The evaluation
of the effects of the compounds on cell cycle in human leukemia cell lines is under way.
Acknowledgment. This work is supported by a PRIN 2009 Project Grant from MIUR, Italy.
References
(1) Pizzirani, D.; et al. Tetrahedron Lett., 2007, 48, 7120-7124
(2) Pizzirani, D.; et al. J. Med. Chem., 2009, 52, 6936-6940
53
P 35
Pyrolysis of tyres: an innovative pilot plant
Loris Giorgini1, Chiara Leonardi1, Giuseppe Bortolani2, Cristian Tosi2
1
Dipartimento di Chimica Industriale ³7RVR0RQWDQDUL´e CIRI-MAM ³0HFFDQLFD$YDQ]DWDH0DWHULDOL´,
Alma Mater Studiorum ± Università di Bologna
2
CURTI S.p.A., Divisione Energia, Via Emilia Est, n.181 - 41100 - MODENA
[email protected]
Recent estimates of the end-life-tyres (ELT) generated in European Union in 2010 is over than 2.5 million
tonnes. This material flow is subdivided in equal part into a variety of recycling applications in order to
obtain materials or energy recovery (1). Among the technological processes available, pyrolysis has the
advantage to be considered both material and energy recovery.
It is a thermal treatment at low temperature in a oxygen free atmosphere. The pyrolysis of ELTs involves
the cracking of the rubber materials generating products in different physical state (Fig.1): a solid fraction
constituted by a steel part, successively recoverable by means of appropriate magnets; a char with high
calorific value usable as such as fuel or as a carbon black or as activated carbon after activation process;
and a gas fraction, partially condensable in an oil (complex mixture of aliphatic and aromatic
compounds). Finally the incondensable fraction (syngas) is a mixture of hydrogen, hydrogen sulphide and
light hydrocarbons (C1-C4).
Each product can be used either as a source of raw materials or as a fuel, moreover, the relative
percentage of each fraction is function of several process variables.
Fig. 1 Subdivision of the pyrolysis products of ELTs
Recent regulatory changes in Italy, that have conducted at the legal framework of WKH ³SURGXFHU
UHVSRQVLELOLW\´, have renewed interests in the development of technological alternatives for the disposal of
these particular waste. The pyrolysis of ELTs, as a single flow of reject, appears an interesting solution,
not only economically competitive, but also advantageous in view of the reduction of pollutants.
In this contest, the Curti S.p.A. has realized an innovative discontinuous static pilot reactor (2), the
system is easily controllable and safe owing to a hydraulic seal that prevents air from entering the
treatment chamber, which was used to pyrolyse tyres (20-60 Kg) at different temperatures between 400
and 600°C. The optimal range of temperature for a fully pyrolysis of the tyre in the pilot plant was
determinate and the influence of the temperature, state and type of tyres and presence of steam on product
yields was also studied in order to identify key features to modulate the process according to the requests
of the market. The pyrolisis products was characterized using different techniques: char was analyzed by
means of SEM, XRF and elemental analysis, oil by XRF; GC-MS and elemental analysis; the
composition of the sygas was monitored on-line during the entire duration of the tests with a μ-GC. In
order to define the fuel properties of the pyrolysis products, the gross calorific value of each fraction, and
the content of sulfur in char and oil was also determined.
(1) ETRMA. End of life tyres ± A valuable resource with growing potential ± 2011 edition.
(2) Bortolani G., Costarini I., Bonicelli I.D., EP1013992, 2000.
54
P 36
Label-Free Approach For Dopamine Sensing Based on Electrolyte-Gated Organic
Field-Effect Transistor (EGOFET)
1,2
Francesca Leonardi, 2Stefano Casalini, 2Tobias Cramer, 2Fabio Biscarini.
1
2
Alma Mater Studiorum, Università degli Studi di Bologna, via Zamboni 33, 40126, Bologna Italy.
Consiglio Nazionale delle Ricerche, Istituto per lo Studio dei Materiali Nanostrutturati (CNR-ISMN), via
P. Gobetti 101, 40129, Bologna, Italy.
[email protected]
Log [ΔVth/V]
Dopamine (DA) is a neurotransmitter that plays a central role in human brain acting on behaviour,
cognition, voluntary movement, motivation, working memory, learning, etc. DA unbalance gives rise to
different neurological disorders, such as Parkinson Disease.
Many techniques have been succesfully exploited for dopamine detection, such as capillary
electrophoresis, mass spectroscopy and high-performance liquid chromatography reaching high level of
sensitivity, but none of them are suitable for real-time monitoring. Organic Field-Effect Transistors
(OFETs) rapresent a promising platform for creating chemical and biochemical sensors. OFET sensors
are compatible with flexible and bio-inspired materials. Recently they have been successfully used in
aqueous environment thanks to different configurations, such as the organic electrochemical transistors
(OECTs), OFETs and EGOFET. In the last year, Tang and coworkers(1) have shown an OECT capable to
detect dopamine up to nM scale due to the DA oxidation, which modulates the dedoping of the
conductive polymer. EGOFETs are another viable route to fabricate stable OFETs in liquid environment,
and they take advantage of the capacitive coupling between the organic semiconductor (OS) and the gate
electrode by means of an electrolyte(2). The gate/electrolyte and OS/electrolyte interfaces are crucial for
the EGOFET performance.
Here, we use a poly(3-hexylthiophene)-based
EGOFET (Fig.1 (a), (c)) whose sensing element is the
Au gate properly functionalized by a multi-layer selfassembled monolayer composed by cysteamine and
4-formylphenyl boronic acid. The analyte recognition
is guaranteed by the chemical affinity between the
boronic moiety and dopamine (namely a diol) as
depicted in Fig. 1 (b). The electrical performance of
our device has been proved to be dependent on the
DA amount adsorbed onto the gate down to the picomolar scale (Fig. 2). In particular the drain-source
current decreases increasing the DA concentation, and
Fig. 1 (a) Schematic pictures and (c) photograph of our devices
our study explains this behavior in terms of implemented by a poly(dimethylsiloxane) pool for confining a
capacitance and threshold voltage changes related to droplet of phosphate buffer solution (PBS). (b) Gate
functionalization steps: (1) cysteamine, (2) 4-formylphenyl
gate/electrolyte interface (see Fig.3).
boronic acid and (3) dopamine dopamine.
In conclusion, we present an ultra-sensitive, labelE G
free, non-oxidative and low-cost
-0.4
approach to detect dopamine.
-0.6
Furthermore, our sensing strategy
-0.8
de-couples the sensing system
-1.0
sensitivity equal to 0.1
from the electronic transducers
-1.2
opening the way towards novel
-1.4
technological solutions (3).
-1.6
-12
-10
-8
-6
-4
-2
-1
Log[conc/mol⋅l ]
Fig. 2 Sensitivity of our sensor
respect to ΔVth
Fig. 3 Transfer Characteristics are acquired in
linear regime (VDS -0.1V) for each DA
concentration
(1) Tang, H.; Lin, P.; Chan, H. L. W.; Yan, F.; Biosensors and Bioelectronics, 2011, 26, 4559-4563.
(2) Kergoat, L.; Herlogsson, L.; Braga, D.; et al.; Adv. Mater., 2010, 22, 2565-2569.
(3) Casalini, S.; Leonardi, F.; Cramer, T.; Biscarini, F.; Org. Electron. 2012, http://dx.doi.org/10.1016/j.orgel.2012.10.027.
55
P 37
Blue and highly emitting Ir(IV) complexes by an efficient photoreaction of
green luminescent Ir(III) complexes
Mirko Locritani, Enrico Marchi, Marco Bandini, Paola Ceroni and Vincenzo Balzani
[email protected]
8QLYHUVLWjGL%RORJQD'LSDUWLPHQWRGLFKLPLFD³*&LDPLFLDQ´
Cyclometalated [Ir(III)] complexes have received a great deal of interest in a variety of photonic
application such as biological labeling reagents (1), photosensitizers for light-driven catalytic water
reduction, sensors of temperature (2), oxygen (3) and metal ions.
In particular, the most important application of the [Ir(III)] complexes is as emitters in
electroluminescent devices (4), including organic light-emitting devices (OLED) and white lightemitting diodes (WOLED). This is due to their luminescent excited states that are triplet in nature,
relatively short excited-state lifetimes, high photoluminescence quantum yields (5) and easy color
tuning through ligand-structure control. The triplet nature of the emission is of great importance. In
fact, in electroluminescent device the luminescence from a triplet state allows the harvesting of both
the singlet and triplet excitons, produced when electrons and holes recombines.
Most of the [Ir(III)] complexes used in OLEDs are based on tris-cyclometalated Ir(III), [Ir(C^N)3],
or neutral heteroleptic bis-cyclometalated [Ir(C^N)2(L^X)] complexes (C^N) = C-,N-donor
cyclometalating ligand, L^X = ancillary ligand.
Focusing on the development in the area of functionalized [Ir(III)] complexes, much efforts have
been made to obtain sky-blue and stable [Ir(III)] phosphorescent complexes (6). In particular we
report the synthesis of cyclometalated [Ir(III)] diastereoisomers and easy separation by
conventional flash chromatography.
These complexes are generally synthesized through a two-step process:
- WKH ILUVW VWHS EHLQJ D UHDFWLRQ EHWZHHQ WKH +&A1 OLJDQG DQG ,U&O ‡Q+2 WR IRUP D GLFKORUREULGJHGGLQXFOHDU,U,,,GLPHU>,U&A1ȝ-Cl)]2;
- the second step consist in the condensation of chloro bridged iridium(III) complexes with chiral
bis- oxazoline, which turns into the formation of diastereomeric mixture
(1) Q. Zhao, S. J. Liu, F. Y. Li, Dalton Trans. 2008, 3836-3840.
(2) L. H. Fisher, M. I. J. Stich, Chem. Eur. J. 2009, 15, 10857-10863.
(3) Q. Zhao. F. Li, C. Huanga, Chem. Soc. Rev. 2010, 39, 3007-3030.
(4) (a) Highly Efficient OLEDs with Phosphorescent Materials, ed: H. Yersin 2007; Wiley-VCH Berlin. b) G. M.
Farinola, R. Ragni, Chem. Soc. Rev. 2011, 40, 3467±3482.
(5) C. Ulbricht, B. Beyer, C. Friebe, A. Winter, Adv. Mater. 2009, 21, 4418-4441.
(6) A. B. Tamayo, B. D. Alleyne, P. I. Djurovich, S. Lamasky, I. Tsyba, N. N. Ho, R. Bau, M. E. Thompson, J. Am.
Chem. Soc. 2003, 125, 7377.
56
P 38
SYNTHESIS AND REACTIVITY OF N-METALLO-KETENEIMINES
LONG SHA,1 QIN WENLING,1 BONGINI ALESSANDRO1 and PANUNZIO MAURO2
1
Dipartimento dL&KLPLFD³*&LDPLFLDQ´8QLYHUVLWD¶'L%RORJQD
Via Selmi, 2 40126 Bologna
2
ISOF-CNR Dipartimento dL&KLPLFD³*&LDPLFLDQ´
Via Selmi, 2 40126 Bologna.
[email protected]
Ketene imines belong to a more general class of compounds known as cumulene, molecules
presenting at least two or more cumulative double bonds.[1] Ketene imines can be represented by the
resonance structures (1) and (2) which emphasize the nucleophilic properties of the heteroatom and the Ecarbon, and by structure (3), which accounts for the electrophilic nature of the D-carbon (Chart 1).
R1
R
2
R1
R3
C C N
R2
1
R2
XM(L)n
C C N R3
R2
N C C
R1
( P)
pka=22-32
2
E
Nu
R1 LDA (L)nM
C
R2
3
E
N
R1
C C N R3
(L)nM N C C
R1
(L) nM
R1
N C C
2
(M) R
R2
Chart 1
N-metallo keteneimines (MKIs), bearing as substituent at nitrogen a metal as Si,[2] Sn,[3] Cu[4] and
Al,[3] are a special class of ketene imines. They can be considered a stable neutral form of the
corresponding metallated (Li, Na, K) nitrile. In the course of the presentation, the results obtained on the
reactivity of MKIs versus different electrophiles (aldehydes,[5] isocyanates,[6] epoxides) will be discussed.
Particular emphasis will be dedicated to the aldol type reaction with the formation of enantiomerically
pure compounds (epc) using as electrophilic partner an optically pure electrophile [e.g. (D-hydroxyprotected)-aldehyde].[5] The factors influencing the stereoselectivity and the best tuning of these factors,
to achieve high chemical yields and diastereo-control, if it is the case, will be discussed as well.
C C N
R1
OPg
For E =
H
*
O
R
N
M(L)n
R2
E
OM(L)n
R
N
R1
R1
*
E
R2
* *2 *
R
For E =
R
OPg
R1
*
*
R2
R
OM(L)n
O
N
For E =
N
O
O C N R
R1
*
N
R
R2 H
Chart 2
[1]
[2]
[3]
[4]
[5]
[6]
a) G. R. Krow, Angew. Chem. Int. Ed. 1971, 10, 435-449;b) M. Alajarin, M. Marin-Luna, A.
Vidal, Eur. J. Org. Chem. 2012, 2012, 5637-5653 and references therein cited.
S. E. Denmark, T. W. Wilson, Angew. Chem. Int. Ed. 2012, 51, 9980-9992.
S. Long, W. Qin, M. Panunzio, Unpublished Results.
L. Yin, M. Kanai, M. Shibasaki, J. Am. Chem. Soc. 2009, 131, 9610-9611.
S. Long, M. Panunzio, W. L. Qin, A. Bongini, Manuscript in preparation.
W. L. Qin, S. Long, M. Panunzio, A. Bongini, Synthesis 2012, 44, 3191-3196.
57
P 39
Synthesis and biological evaluation of memoquin analogs as potential muscarinic M1
UHFHSWRUDOORVWHULFPRGXODWRUVDFKDOOHQJHLQWKHWUHDWPHQWRI$O]KHLPHU¶VGLVHDVH
1
V. Maestri, 2M. Baiula, 2G. Carbonari, 1A. Minarini, 1M. L. Bolognesi, 2S. Spampinato, 1C. Melchiorre.
1
Department of Pharmacy and Biotechnology-FaBiT, University of Bologna, Via Belmeloro 6, 40126
Bologna, Italy.
2
Department of Pharmacy and Biotechnology-FaBiT, University of Bologna, Via Irnerio 48, 40126
Bologna, Italy.
[email protected]
$O]KHLPHU¶V GLVHDVH $' WKH PRVW FRPPRQ IRUP RI GHPHQWLD LQ WKH HOGHUO\ LV DQ LUUHYHUVLEOH PXOWLfactorial neurodegenerative disorder characterized by memory loss and cognitive impairment. The most
important hallmarks in AD are: amyloid ($ȕ SODTXHV QHXURILEULOODU\ WDQJOHV DQG GHJHQHUDWLRQ RI
cholinergic neurons (1). Muscarinic receptors (mAChRs), a family of five G-protein coupled receptors,
have also been implicated in the pathophysiology of AD. In particular, post-synaptic M1 mAChRs have a
major role in memory, learning and cognition which is impaired in AD (2). Thus, targeting M1 mAChRs
might be of therapeutic value for the treatment of this neurodegenerative disease.
The aim of this project was to synthesize multi-target-directed-ligands (MTDLs) which would target an
allosteric site on the M1 receptor rather than the highly conserved orthosteric acetylcholine binding site.
The rationale that led to the design of these new compounds was based on the structural similarity
between TBPB (3), a selective M1 mAChRs allosteric agonist, and memoquin (4) bearing a benzoquinone
moiety. The first class of compounds was obtained through Michael addition between a benzoquinone
moiety bearing different substituents, and a 2-methoxy-benzylamine chain which might mimic the amine
chain of TBPB. The substituents on the benzoquinone group exploit different electronic and lipophilic
effects DFFRUGLQJWRWKH&UDLJ¶VGLDJUDP
The second class of compounds were obtained replacing the benzoquinone moiety with carbamic or
amide groups to study whether the benzoquinone plays a role in the interaction with the allosteric site of
the M1 mAChR subtype. The molecules containing an amide group were synthesized through
multicomponent reactions between a secondary amine, an aldehyde and an isocyanide.
The new compounds were investigated using M1 receptor binding assay with [3H]-N-methyl-scopolamine
and in functional studies (cAMP assay). Regarding the molecules bearing a benzoquinone moiety, VM6
and VM2 seem to be the most promising compounds.
OCH 3
H
N
O
N
N
OCH 3
6
N
H
N
6N
N
O
HN
TBPB
O
Memoquin
O
O
N
N
H3CO
O
H3CO
O
VM6
N
VM2
N
(1) BLENNOW, K.; DELEON, M. J.; ZETTERBERG, H. Lancet 2006, 368, 387-403.
(2) WESS, J.; EGLEN, R. M.; GAUTAM, D. Nat. Rev. Drug Discov. 2007, 6, 721-733.
(3) LEBOIS, E. P.; BRIDGES, T. M.; LEWIS, L. M.; DAWSON, E. S.; KANE, A. S.; XIANG, Z.; JADHAV, S. B.; YIN, H.;
KENNEDY, J. P.; MEILER, J.; NISWENDER, C. M.; JONES, C. K.; CONN, P. J.; WEAVER C. D.; LINDSLEY, C. W. ACS
Chem. Neurosci. 2010, 2, 104-121.
(4) BOLOGNESI, M. L.; CAVALLI, A.; MELCHIORRE, C. Neurotherapeutics 2009, 6, 152-162.
58
P 40
Oxidative stress and oral tocotrienol supplementation a novel approache to the
complementary therapy of friedreich ataxia
Manfredini Stefano, Vertuani Silvia, Malisardi Gemma (Department of Pharmaceutical Sciences
and Ambrosialab, University of Ferrara, Italy)
Marini Marina, Abruzzo Provvidenza Maria, Marchionni Cosetta (Department of Histology,
Embryology, and Applied Biology, University of Bologna, Italy.
Raggi Maria Augusta, Bugamelli Francesca., Morganti Emanuele (Department of Pharmaceutical
Sciences, University of Bologna,)
Modesti Alessandra, Gamberi Tania (Department of Biochemical Sciences, University of Florence,
Italy)
Ferreri Carla (ISOF, Consiglio Nazionale delle Ricerche, Bologna, Italy.)
Pini Antonella, Ghezzo Alessandro (Child neurology Unit, Ospedale Maggiore – Bologna, Italy)
Fortuna Filippo (Ospedale S. Orsola – Bologna)
In this work, we investigated white blood cell gene expression of SOD-1, SOD-2, catalase,
GPX-1, GSR and GSTM-1; plasma content of GSH and GSSG; plasma Oxygen Radical
Absorbance Capacity; amount of plasma carbonylated proteins; urinary levels of Hexanoyl-Lysine
adduct; lipid composition of erythrocyte membranes.
Oxidative stress is always associated with Friedreich’s Ataxia (FRDA)1 also accompained by
impaired mitochondrial functions2. Patients are currently treated with idebenone, a CoQ10 analogue,
believed effective in view of its ability to counteract free radical damages.
Vit. E is known to be effective on oxidative stress related pathologies3, taking into account our
esperience in the field of the class of natural vitamin E “tocotrienol” we have started the present
investigation in order to develop a model useful to investigate the efficacy of a tocotrienol based
approaches on oxidative stress damage protection. A mixture (OXI-3 internal reference name) of
enantiomerically pure tocotrienols (alpha, beta, gamma and delta) has been selected and tested in
patients monitoring the above reported different biochemical parameters. The pilot investigation
was conducted on five young FRDA patients who assumed OXI-3 (equivalent to 5 mg/kg/day), for
two months. The wide array of different markers consistently pointed to the presence of oxidative
stress in FRDA patients, despite the fact that the idebenone therapy had not been discontinued.
However, even a two month low-dose tocotrienol supplementation led to the decrease of oxidative
stress indexes and to parameter values that approached those of healthy controls. Moreover, there
are evidences that a longer tocotrienol treatment may be more effective in reducing oxidative stress.
1. Santos R, Lefevre S, Sliwa D, Seguin A, Camadro JM, Lesuisse E. Comprehensive invited review friedreich’s
ataxia: molecular mechanisms, redox considerations and therapeutic opportunities. Antioxid Redox Signal. 2010 Feb
16.
2. Lodi R, Cooper JM, Bradley JL, Manners D, Styles P, Taylor DJ, Schapira AHV. Deficit of in vivo mitochondrial
ATP production in patients with Friedreich ataxia. Proc.Natl.Acad.Sci.USA 1999;96:11492-11495
3. Khanna S, Roy S, Parinandi NL, Maurer M, Sen CK. Characterization of the potent neuroprotective properties of
the natural vitamin E alpha-tocotrienol. J Neurochem. 2006;98(5):1474-1486
59
P 41
Novel asymmetric naphthalenediimide-polyamines conjugates as anticancer agents
Chiara Marchetti1, Andrea Milelli2, Vincenzo Tumiatti2, Claudia Sissi3, Maria Laura Greco3,
Huanzhou Li4, Heather M. Wallace4 and Anna Minarini1
1
Department of Pharmacy and Biotechnology, Alma Mater Studiorum-University of Bologna,
Bologna, Italy
2
Department of life quality studies, Alma Mater Studiorum-University of Bologna, Rimini, Italy
3
4
Department of Pharmaceutical Sciences, University of Padova, Padova, Italy
Kosterlitz Centre for Therapeutics, Institute of Medical Sciences, University of Aberdeen, UK
[email protected]
The development of novel chemotherapeutic agents and new strategies for cancer treatment
represent an active research fields stimulated by the discovery of both new biological targets and
drugs without serious side effects. Several anticancer agents recently published in literature are
characterized by Naphtalene diimide (NDI) scaffold, especially those interacting with DNA as
intercalators 1. Additionally, some derivatives characterized by this core are able to stabilize Gquadruplex DNA structure2. Recently, we reported a new series of NDI derivatives as
antiproliferative agents3, characterized by NDI scaffold properly functionalized with two basic side
chains and among these, the most interesting compound was 1, characterized by one methoxy group
on the two aromatic rings. Polyamines are a class of naturally-occurring compounds responsible for
a plenty of fundamental biochemical actions, particularly they play an important role in cell
proliferation. Polyamine (PA) analogues have been extensively investigated for their potential
pharmacological applications in different diseases4,5. Furthermore, several multiple transport
systems (PTS) have been identified allowing polyamines to be distributed throughout body and
several anthracene-polyamines conjugates demonstrated the ability to hit cancer cells
overexpressing PTS6.
In order to search new anticancer agents characterized by a MTDLs biological profile, we explored
the possibility to insert on the NDI scaffold, a polyamine mojety (NDI-PAs). These new conjugates
could improve the anticancer activity and/or selectivity of 1 by reaching several key targets
including DNA, through PTS interaction and transport inside the cells (Figure 1). The PA moiety
was modified and both triamines and tetrammines were condensed onto NDI scaffold.
60
References
(1) Brana, M. F., Ramos, A. Naphthalimides as anti-cancer agents: synthesis and biological activity. Curr. Med. Chem.
Anticancer Agents 2001, 1, 237-255.
(2) Balasubramanian, S., Neidle, S. G-quadruplex nucleic acids as therapeutic targets. Curr. Opin. Chem. Biol. 2009,
13, 345-353.
(3) Tumiatti, V., Milelli, A., Minarini, A. et al. Design, synthesis, and biological evaluation of substituted naphthalene
imides and diimides as anticancer agent. J. Med. Chem. 2009, 52, 7873-7877.
(4) Casero, R. A., Jr., Woster, P. M. Recent advances in the development of polyamine analogues as antitumor agents.
J. Med. Chem. 2009, 52, 4551-4573.
(5) Wallace, H. M. The polyamines: past, present and future. Essays Biochem. 2009, 46, 1-9.
(6) Palmer, A. J., Wallace, H. M. The polyamine transport system as a target for anticancer drug development. Amino
Acids 2009, 38, 415-422.
61
P 42
Synthesis and anticancer activity evaluation of new highly modified nucleolipids
Daniela Perrone1, Elena Marchesi1, Massimo Capobianco2, Lara Mari1, Chiara Massarenti1, Maria Luisa
Navacchia2, Fabio Sforza3, Olga Bortolini1
1
Department of Chemical and Pharmaceutical Sciences, University of Ferrara, Ferrara
2
3
ISOF CNR, Bologna
Department of Medicinal Sciences, University of Ferrara, Ferrara
The therapeutic efficacies of bile acids have been widely demonstrated in various liver diseases suggesting that they might
protect hepatocytes against common mechanism of liver damage (1). Although it has been shown to prevent apoptotic cell
death in certain cell lines, bile acids significantly inhibited cell growth and induced apoptosis in cancer cells. Nucleoside
analogues have proven useful in the treatment of viral infections and several nucleoside drugs have been developed as cancer
treatment agents (2). Indeed, nucleoside analogs were among the first oncology drugs ever developed. Following up these
considerations, we envisaged the synthesis of new highly modified nucleolipids by using a "click chemistry" approach.
R
R
COOMe
COOMe
Y
HO
Y
N3
X
X
1 a,b,c
2 a,b,c
1a UDCA Y= OH, X= H, R= H
1b CDCA Y=H, X= OH, R= H
1c CA Y= H, X= OH, R= OH
C-3 azides derivates 2 a,b,c were synthesized starting from methyl esters of UDCA, CDCA and CA through a double
nucleophilic substitution reaction: hydroxyl group at C-3 was first converted into iodo-derivate then into azide with overall
retention of configuration. Finally, modified bile acids 2 a,b,c were linked with a series of new deoxyadenosine derivates
functionalized at C-8 with different alkyne residues through a 1,2,3-triazole ring by means of copper-catalyzed Huisgen
cycloaddition.
COOMe
R
linker
H
+
N3
X
2 a,b,c
Y
C
N
N
C
N
HO
H
H
NH2
NH2
O
OH
X
Y
N
N N
N
N
HO
H
H
H
linker N
H
H
3
different types of linker
MeOOC
R
O
OH
N
N
H
H
H
4
These new molecules were investigated for anti-proliferative activity in human leukemic T cell lines such as Jurkat and K562
cells.
Every detail concerning synthesis and anticancer activity will be discussed.
(1) Yung Hyun Choi, International Journal of Oncology, 2001, 18, 979-984.
(2) Yoon-Suk Lee, Bioorganic & Medicinal Chemistry Letters, 2009, 19, 4688-4691.
62
P 43
Switch on - switch off signal in a MOF-guest crystalline device
P. P. Mazzeo1, L. Maini1, D. Braga1, G. Valenti1, F. Paolucci1, M. Marcaccio1, A. Barbieri2, B. Ventura2
1 Dipartimento di Chimica “G.Ciamician”, Università di Bologna, Via Selmi 2, 40126 Bologna, Italy
2 Istituto per la Sintesi Organica e la Fotoreattività (ISOF) – CNR,Via Gobetti 101, 40129 Bologna, Italy.
[email protected]
In the last decades, crystal engineering has developed a new concept of supramolecular chemistry in the
solid state. Crystal engineers are devoted to the design and synthesis of new crystalline solids with
desired physical and chemical properties starting from an adequate choice of molecular building blocks
and framework structures.
The crystal engineering paradigm has led us to the idea of using this approach to construct crystalline
devices. As a device is “a thing made for a particular purpose” which is made of different pieces with
different functionalities assembled together, in the same way, a crystalline device is a crystal made of
different molecules with different chemical functionalities assembled together to obtain a final material
whose properties can be activated by appropriate external stimuli. Metal-organic frameworks (MOFs),
which are nowadays extensively studied for biology1, drug delivery2, gas storage/uptake3, separation4,
sensing5 and catalysis,6 are good candidates for the construction of such crystalline devices, since they are
characterized by a robust framework and cavities to allocate guest molecules.
In our approach the crystalline device is based on the idea of having a guest molecule trapped into a
luminescent MOF which can be subjected to external physical “stimuli” to modify host-guest interactions
within the MOF and consequently the host luminescence.7,8 From this viewpoint a crystalline device can
be considered as a higher level step of crystal engineering since the final properties of the device are
derived from the tunable combination of the specific properties of the host and of the guest.
A metal organic framework (MOF) based on the cluster of [Cu4I4DABCO2] (1) (DABCO=1,4diazabicyclo[2.2.2]octane) MOF 1 shows a bright emission with maximum at 556 nm and emission
quantum yield of 0.53 in the solid state. When, during the synthesis, the large cavities of the MOF are
loaded with different amounts of ferrocene (FeCp2, [(η5-C5H5)2Fe(II)]), MOF 1 luminescence decreases
with the increase of ferrocene content, reaching an almost complete quenching for 3.5% w/w of cage
loading. When an electric potential is applied to the [email protected] 1 deposited onto an ITO glass, the
Fe(II)Cp2 is oxidized to Fe(III)Cp2+, and the MOF 1 emission is switched on again, indicating that a
photoinduced electron transfer reaction is contributing to the quenching process.
(1) McKinlay, A. C.; Morris, R. E.; Horcajada, P.; Férey, G.; Gref, R.; Couvreur, P.; Serre, C. Angew. Chem. Int. Ed. 2010, 49,
6260.
(2) Horcajada, P.; Serre, C.; Maurin, G.; Ramsahye, N. A.; Balas, F.; Vallet-Regì, M.; Sebban, M.; Taulelle, F.; Férey, G. J. Am.
Chem. Soc. 2008, 130, 6774.
(3) Ferey, G. Chem. Soc. Rev. 2008, 37, 191.
(4) Li, J.-R.; Kuppler, R. J.; Zhou, H.-C. Chem. Soc. Rev. 2009, 38, 1477.
(5) Achmann, S.; Hagen, G.; Kita, J.; Malkowsky, I.; Kiener, C.; Moos, R. Sensors 2009, 9, 1574.
(6) Proch, S.; Herrmannsdörfer, J.; Kempe, R.; Kern, C.; Jess, A.; Seyfarth, L.; Senker, J. Chemistry - A European Journal
2008, 14, 8204.
(11) Cui, Y. J.; Yue, Y. F.; Qian, G. D.; Chen, B. L. Chem. Rev., 112, 1126.
(12) Allendorf, M. D.; Bauer, C. A.; Bhakta, R. K.; Houk, R. J. T. Chem. Soc. Rev. 2009, 38, 133.
63
P 44
1
Influence of capsule piercing on aerodynamic performance in DPIs
M. V. Carra, 1F. Martinelli, 1M. Miozzi, 1A. G. Balducci, 2M. Citterio, 1P. Colombo, 1F. Buttini
1
University of Parma, Department of Pharmacy, Viale G.P. Usberti 27/A, Parma
2
Palstiape S.p.a, via 1° Maggio, Osnago (Lecco)
[email protected]
Purpose: To evaluate the influence of capsule piercing position on aerodynamic behaviour in different
Dry Powder Inhaler monodose devices.
Method: A lactose blend containing Formoterol Fumarate (FORADIL®, Novartis) was used as a model
formulation. Three different devices were selected to aerosolize the powder: RS01® (Plastiape Spa),
Turbospin® (PH&T Pharma) and HandiHaler® (Boehringer Ingelheim). All three hold size 3 capsules,
piercing them at different positions. Control data was collected from each device. Following this, a fresh
capsule was pierced in one of the devices, then removed and aerosolised within a second device. This
procedure was repeated for all possible combinations.
Aerodynamic performance of the formoterol fumarate blend was investigated using Next Generation
Impactor (Copley UK) following USP 34.
Results: The RS01® device showed the highest emitted dose and fine particle dose (FPD) around 10.71
μg and 4.15 μm, respectively. The other devices gave lower values: the HandiHaler® emitted dose and
FDP were 9.92 μg and 3.13 μm while the Turbospin® gave 9.00 μg and 3.35 μm, respectively.
Furthermore, when inhalers were combined with capsules pierced with other devices RS01® again
showed the best performance with a FPF value higher than 37%. Turbospin® and HandiHaler® loaded
with capsules pierced in other devices showed lower FPF values between 22% and 35%. Fine particle
dose (FDP) was significantly higher in the case of RS01® compared to other devices (p-value 0.0073).
Conclusions: This study showed that the position of capsule piercing and choice of device influence the
emitted dose and the performance of the formulation. The RS01® device showed the optimum capsule
piercing position and aerosolisation of the powder, giving the highest fine particle fraction.
64
P 45
A New Class of Conformationally Constrained Bicyclic Silylated Diarylprolinol
Organocatalysts
Marco Lombardo, Elisa Montroni, Arianna Quintavalla, Claudio Trombini
8QLYHUVLWjGHJOL6WXGLGL%RORJQD'LSDUWLPHQWRGL&KLPLFD³*&LDPLFLDQ´
via Selmi 2, 40126, Bologna - Italy.
[email protected]
$PRQJ WKH FODVV RI ³SULYLOHJHG´ RUJDQRFDWDO\VWV -¡UJHQVHQ-Hayashi silylated diarylprolinols (1) have
been successfully used in a variety of useful synthetic transformations, almost invariably with very high
stereoselectivity values.1
One of the major drawback of this class of compounds is their lability towards desilylation reactions,
confirmed by the fact that also commercially available catalysts contain at least 10±15% of their
deprotected analogues.2 The corresponding desilylated diarylprolinols are much less active catalysts, due
to the almost irreversible reaction with carbonyl compounds to afford oxazolidines.
Finally, the free rotation of diarylmethanol group around C-C bond can bring to the formation of different
preferred conformations of the active intermediates.
Here we wish to present a new family of conformationally constrained bicyclic silylated diarylprolinol
analogues (2), deriving from natural trans-L-4-hydroxy-proline, characterized by a superior hydrolitic
stability towards desilylation and by a very good catalytic efficiency.
Their preparation and their activity in different organocatalytic transformations based on the iminium
ion/enamine reactivity-type will be thoroughly presented.
(1) a) M. Marigo, D. Fielenbach, A. Braunton, A. Kjaersgaard and K. A. Jørgensen, Angew. Chem., Int. Ed., 2005, 44, 3703±
3706. b) M. Marigo, T. C. Wabnitz, D. Fielenbach and K. A. Jørgensen, Angew. Chem., Int. Ed., 2005, 44, 794±797. c) Y.
Hayashi, H. Gotoh, T. Hayashi and M. Shoji, Angew. Chem., Int. Ed., 2005, 44, 4212±4215. d) M. Marigo, J. Franzén, T. B.
Poulsen, W. Zhuang and K. A. Jørgensen, J. Am. Chem. Soc., 2005, 127, 6964±6965. e) A. Mielgo and C. Palomo, Chem.±
Asian J., 2008, 3, 922±948. f) K. /-HQVHQ*'LFNPHLVV+-LDQJà$OEUHFKWDQG.$-¡UJHQVHQAcc. Chem. Res., 2012,
45, 248-264.
(2) M. H. Haindl, M. B. Schmid, K. Zeitler and R. M. Gschwind, RSC Advances, 2012, 2, 5941±5943.
65
P 46
Determination of GHB by Means of Capillary Electrophoresis
with Indirect UV Detection
1*
Emanuele Morganti, 1Roberto Mandrioli, 1Maria Addolorata Saracino, 2Maria Chiara Pieri,
3
Ernst Kenndler, 1Maria Augusta Raggi
1
Laboratory of Pharmaco-Toxicological Analysis, Department of Pharmacy and BioTechnology - FABiT,
University of Bologna, Via Belmeloro 6, 40126 Bologna, Italy.
2
³&DUSDFFLR´6HU7$GGLFWLRQ6HUYLFH%RORJQD/RFDO+HDOWK8QLW$XWKRULW\ Via Carpaccio 2, 40139
Bologna, Italy.
3
Max F. Perutz Laboratories, Inst. Med. Biochem., Medical University of Vienna, Vienna Biocenter
(VBC), Dr. Bohr Gasse 9/3, 1030 Vienna.
[email protected]
GHB (J-hydroxybutyric acid, Figure 1a) is an endogenous neurotransmitter that binds to specific
receptor, whose precise function remains unclear. It can also be considered a GABA (J-aminobutyric
acid, Figure 1b) derivative that readily cross the blood-brain barrier and is thus able to produce central
nervous system (CNS) depression. Today GHB is used in clinical context to treat narcolepsy and
alcoholism. In fact, its sedative and GABA-like activity can effectively suppress alcohol withdrawal
syndrome symptoms; moreover, GHB also partially mimics alcohol effects on CNS, thus reducing
craving and inhibiting the voluntary ethanol consumption (1).
Figure 1
O
O
(b) H N
2
(a)
HO
OH
OH
Aim of this study is the development of a reliable analytical method for the analysis of GHB in DBS
(Dried Blood Spots) of alcohol-dependent patients undergoing treatment with the drug (Alcover®).
DBS is a blood sampling technique where small volumes of blood are spotted and dried on a suitable
filter paper. The dried samples can easily be shipped to an analytical laboratory and analysed. A capillary
electrophoretic method with indirect UV detection was used, since GHB does not possess any
chromophore chemical group. The migration times and the sensitivity were optimised by varying the
dimensions of the capillary, the voltage and the composition of the Background Electrolyte (BGE).
The DBS sample pre-treatment, based on protein precipitation, produces clean samples, devoid of any
interfering endogenous compound.
The preliminary assays on real DBS from alcohol-dependent patients gave satisfactory results. The
method is currently undergoing validation for the purpose of demonstrating its applicability to
Therapeutic Drug Monitoring (TDM).
(1) 0$5(00$1,$*,3$1,33529$,/3$&,1,0'(//¶2662/0$5(00$1,, I. Int. J. Environ. Res.
Public Health 2011, 8,2816-2827
This research was supported by a grant from Laboratorio Farmaceutico C.T., Sanremo (IM).
*
Emanuele Morganti is a research grant holder, founded by the Department for Antidrug Policies ±
Ministry for International Cooperation and Integration (Italy), within the VulCan Project.
66
P 47
Solid state investigation of water soluble vitamins: riboflavin and
folic acid
Saverio Nanna1, Dario Braga1, Fabrizia Grepioni1 and Laura Chelazzi1
1
Departament of Chemistry G. Ciamician, University of Bologna, Italy.
Folic acid and riboflavin are water soluble vitamins, that cannot be synthesized
by humans and their levels in human body depend on diet. Folic acid (vitamine
B9) and its derivatives act as coenzymes for synthesis and metabolism of many
amino acids and nucleotides by single carbon transfer reactions. Riboflavin
(vitamine B2) plays a key role in the metabolism of carbohydrates, amino acids
and lipids. Folic acid and riboflavin deficiency can lead to nervous system
diseases and others illnesses [1]. The aim of this project is to determine the crystal
structures of riboflavin, folic acid, their salts and co-crystals and to investigate
the relationship between crystal structure and physico-chemical parameters such
as melting point, thermal stability and intrinsic dissolution rate (IDR). It is
important to rationalize these properties and their differences in order to improve
bio-availability compared to native vitamins. The crystal structures, determined
from X-ray powder data, of riboflavin and folic acid (dihydrate form) at room
temperature are presented together with a new crystalline form at high
temperature, i.e. anhydrous folic acid. Folic acid salts and ionic co-crystals have
also been synthesized and characterized via X-ray powder diffraction, DSC,
TGA and IDR.
(a)
(b)
Figure 1. riboflavin (a) and folic acid (b) schemes
References
(1) H.M. Said Biochem J. (2011), 437, 357-372
67
P 48
Fluorescence Photoswitching by Intramolecular Electron Transfer in a
Perylenebisimide-Diarylethene System
1
Mirco Natali, 2 Martin Berberich, 1 Franco Scandola, 2 Frank Würthner
1
2
Università di Ferrara, Dipartimento di Chimica, 44121 Ferrara, Italy
Universität Würzburg, Institut für Organische Chemie, Am Hubland, D-97074 Würzburg, Germany
E-mail: [email protected]
Photochromic compounds are important for several technological applications, including the design of
molecular-based optical memories. (1) In particular the possibility of switching fluorescence properties
with such molecules is of great interest in this research field. In the last few years diarylethenes have
evolved as highly promising photochromic molecules for optical data storage because of their durable
persistency and the thermal irreversibility of their closed and open forms. Only recently a new switching
concept has been introduced to allow non-destructive read-out, on the basis of an intramolecular electron
transfer from the fluorophore unit to the diarylethene one. (2,3) To this goal perylenebisimide
fluorophores are very interesting because of their high emission quantum yield and the tunability of their
spectroscopical and electrochemical properties through appropriate substitutions in the bay positions.
In this work we have studied a perylenebisimide-diarylethene system (Figure 1) specifically designed for
on/off fluorescence switching by electron transfer. (4) Particular attention has been devoted to the
investigation of the quenching mechanism by ultrafast spectroscopy techniques.
hν1 (UV)
hν3
hν3
hν2 (vis)
PET
fluorescence
Fig. 1. Representation of the target dyad and its photochemical behavior.
(1) a) Irie, M. Chem. Rev. 2000, 100, 1685-1716; b) Tian, H.; Yang, S.J. Chem. Soc. Rev. 2004, 33, 85-97; c) Tian, H.; Wang,
S. Chem. Commun. 2007, 781-792.
(2) Berberich, M.; Krause, A-M.; Orlandi, M.; Scandola, F.; Würthner, F. Angew. Chem. Int. Ed. 2008, 47, 6616 –6619.
(3) a) Odo, Y.; Fukaminato, T.; Irie, M. Chem. Lett. 2007, 36, 240-241; b) Fukaminato, T.; Doi, T.; Tamaoki, N.; Okuno, K.;
Ishibashi, Y.; Miyasaka, H.; Irie, M. J. Am. Chem. Soc. 2011, 133, 4984–4990.
(4) Berberich, M.; Natali, M.; Spenst, P.; Chiorboli, C.; Scandola, F.; Würthner, F. Chem. Eur. J., 2012, 18, 13651-13654.
68
P 49
Tacrine ± 1,4-Naphtoquinone Heterodimers as Potential Drugs in Alzheimer¶V
Disease Therapy
1, 2
1
Eugenie Nepovimova, 2Marinella Roberti, 3Jan Korabecny, 1Veronika Opletalova, 2Maria Laura
Bolognesi
Department of Pharmaceutical Chemistry and Drug Control, Faculty of Pharmacy in Hradec Kralove,
Charles University in Prague, Heyrovskeho 1203, 500 05 Hradec Kralove, Czech Republic
2
Department of Pharmacy and Biotechnologies, Alma Mater Studiorum, University of Bologna, Via
Belmeloro 6, 40126 Bologna, Italy
3
University Hospital of Hradec Kralove, Sokolska 581, 500 05 Hradec Kralove, Czech Republic
[email protected]
$O]KHLPHU¶V GLVHDVH $' LV D SURJUHVVLYH QHXURGHJHQHUDWLYH GLVRUGHU DVVRFLDWHG ZLWK PHPRU\ ORVV
spatial disorientation, and gradual deterioration of intellectual capacity. The ³cholinergic hypothesis´ of
AD correlates the reduced acetylcholine-mediated neurotransmission with the cognitive decline.(1) Hence,
cholinesterase inhibitors became first-line medication in the treatment of AD. Tacrine was one of the first
cholinesterase inhibitors to be clinically tested, nevertheless it was soon withdrawn because of its
significant adverse effects. Unfortunately, clinical experience showed that therapeutic agents, which act to
correct acetylcholine deficiency, while effective in providing symptomatic relief, have minimal efficacy
in the cure of AD. A new hypothesisWKHVRFDOOHG³DP\ORLGK\SRWKHVLV´RI$' was proposed in early
(2)
¶V ,W FODLPV WKDW WKH FHQWUDO HYHQW LQ $O]KHLPHU¶V GLVHDVH SDWKRORJ\ LV SURGXFWLRQ RI DP\ORLG ȕ
SHSWLGH$ȕDQGLWVVXEVHTXHQWDJJUHJDWLRQ$ȕFRPSULVHVWKHPDMRUFRQVWLWXHQWRIVHQLOHSODTXHVRQHRI
the histopathological hallmarks of AD. Quinones are known as inhibitors of cellular metabolic pathways,
to have anti-cancer, anti-viral and anti-bacterial properties and were shown to inhibit aggregation of
several amyloidogenic proteins in vitro.(3) Some 1,4-naphtoquinone derivatives showed BACE inhibitory
activity, were active on amyloid aggregation and disaggregation of perforPHG $ȕ ILEULOV(4) The aim of
our work was to synthesize differently substituted heterodimers containing tacrine (a symptoms
alleviative agent) and 1,4-naphtoquinone (antiamyloidogenic agent) (Fig. 1). Properly addressed
biological studies will reveal whether these compounds are attractive starting point for the development
of more effective medicines against AD.
Fig. 1. Substituted tacrine ± 1,4-naphtoquinone heterodimers
(1) BARTUS, R. T.; DEAN III, R. L.; BEER, B.; LIPPA, A. S. Science 1982, 217, 408-417
(2) HARDY, J. A; HIGGINS, G. A. Science 1992, 256, 184-185
(3) SCHERZER-ATTALI, R.; SHALTIEL-KARYO, R.; ADALIST, Y. H.; SEGAL, D.; GAZIT, E. Proteins 2012, 80, 19621973
(4) BERMEJO-BESCÓS, P.; MARTÍN-ARAGÓN, S.; JIMÉNEZ-ALIAGA, K. L.; ORTEGA, A.; MOLINA, M. T.;
%8;$'(5$6(25(//$1$*&6È.º$*Biochem Bioph Res Co 2010, 400, 169-174
69
P 50
Self cleaning textile: a basic approach for the photocatalytic characterization
1
1
S. Ortelli, 2M. Blosi, 1,3S. Albonetti, 1,3A. Vaccari, 2A. L. Costa
Centro Interdipartimentale di Ricerca Industriale Meccanica Avanzata e Materiali, Viale Risorgimento 2,
40136 Bologna, Italy
2
CNR-ISTEC,Via Granarolo 64, 48018 Faenza (RA), Italy
3
Dipartimento di Chimica Industriale e dei Materiali, Alma Mater Studiorum ± Università di Bologna,
Viale Risorgimento 4, 40136, Bologna, Italy
[email protected]
In the recent years, the textile industry focused high interest towards nanotechnology, since the use of
nanometric particles increases the degree of adhesion of the treatment and its functionality. Furthermore,
the sizes render them transparent to visible light and, therefore, their presence does not alter the colors,
the hand and the breathability of the fabric. Nanoparticles of metal oxides have a particular affinity for the
natural hydrophilic fibers and may be used in the finishing processes of fabrics to modify the surface
properties and impart new functions to the product (1). In particular, coatings based on TiO2 attracted
particularly attention due to their photocatalytic properties (2) exploitable in processes of stain removal as
well as for antibacterial (3) and DeNOx activity (4). In this scenario TiO2 played the largest role
compared to other semiconductor photocatalysts due to its cost, effectiveness, inert nature and
photostability (5).
In this work the photocatalytic reactivity of nano-TiO2 exploited in self-cleaning properties of textile was
assessed. Different factors affect the photocatalytic efficiency of functionalized fabrics. The
photocatalytic reaction carried out by nano-TiO2 is conditioned by the factors characterizing the titania
nanoparticles interface, i.e. physicochemical surrounding at different interfaces: particle/solution,
particle/substrate and particle/substrate/organic stain.
The photocatalytic reactivity and physicochemical properties such as particle size distribution, specific
surface area, XRD patterns of different nano-TiO2 sols were tested.
The photocatalytic reactivity of nano-TiO2 exploited in self-cleaning properties of textile was assessed
using as a model reaction the degradation of the dye Rhodamine B.
The photocatalytic tests were performed in different conditions as shown in figure 1. From a) to c) set-up,
the freedom degree of the system decreases and the TiO2 reactivity depends in case a) only on the surface
chemistry, while in case b) and c) it is influenced by TiO2-substrate interaction and TiO2/substrate/stain
interaction, respectively. Thus, it was confirmed that the catalytic performances of TiO2 nanosols in case
a) and b) are predictable only on the basis of the photocatalyitic properties assesssed in the case a).
Figure 1. Schematic representation of: a) catalyst in a solution containing organic dye; b) catalyst supported on textile and
immersed in a solution containing organic dye; c) self-cleaning application: catalyst supported on textile stained by organic
dye
(1) M.J. Uddin, F. Cesano, F. Bonino, S. Bordiga, G. Spoto, D. Scarano, A. Zecchina, J. Photochem. Photobiol. A:
Chemistry 2007,189, 286-294.
(2) W. S. Tung, W. A. Daoud, J. Mater. Chem. 2011, 21, 7858-7869.
(3) K. Qi, W. A. Daoud, J. H. Xin, C. L. Mak, W. Tang, W. P. Cheung, J. Mater. Chem. 2006, 16, 4567-4574.
(4) M. Chena, Y. Liu, J. Hazard. Mat. 2010, 174, 375-379.
(5) U. I. Gaya, A.H. Abdullah, J. Photochem. Photobiol. C: Photochem. Rev. 2008, 9 , 1-12.
70
P 51
Easy Formylation of Organoboron Compound
1D.
1Dipartimento
Petruzziello, 1A. Gualandi, 1H. M. Giaffar, 1P. G. Cozzi
di Chimica “G. Ciamician”, Alma Mater Studiorum Università di
Bologna - Via Selmi 2, I-40126 Bologna, Italy
e-mail: [email protected]
Organoboron compounds are key intermediates in organic synthesis, since are most
valuable reagents for Pd-catalysed cross-couplings (Suzuki–Miyaura reactions)(1) and
tolerate a great variety of functional groups. Some of them can also undergo noncatalysed C–C bond forming reactions with various electrophiles.(2) Metal-Free
reactions of organoboron compounds, in particular halogenations and nitrosations, have
been recently reported with good yields under mild conditions.(3)
Recently the use of carbocations in selective reactions has become increasingly
important. The benzothiazolium salt is quite electrophylic and is generally used as
readily available synthon for organic synthesis for a large series of transformations. It
gives the possibility to introduce functionalisations groups after lithiation and
successive alkylation with other electrophiles, or by reductive or oxidative cleavage.(4)
In this contest, we disclose the easy formylation with benzodithiolylium salt of a broad
range of organoboron compounds containing both electron-donating and electronwithdrawing groups.
References:
(1) Miyaura, N.; Suzuki, A. Chem. Rev. 1995, 95, 2457.
(2) Berionni, G.; Maji, B.; Knochel, P.; Mayr, H. Chem. Sci. 2012, 3, 878-882.
(3) a) Molander, G. A.; Cavalcanti, L. N. J. Org. Chem. 2011, 76, 71957203; b) Molander, G. A.;
Cavalcanti, L. N. J. Org. Chem. 2012, 77, 44024413.
(4) Gualandi, A.; Emer, E.; Guiteras Capdevila, M.; Cozzi, P. G. Angew. Chem. Int. Ed. 2011, 50,
7842-7846.
71
P 52
Peculiar properties of the lactic acid bacteria used as microbial starter in fermented
meat manufacturing: anti-Listeria activity and probiotic potential
Mina Popovic, Alberto Amaretti, Stefano Raimondi, Maddalena Rossi
Dep. of Life Science, University of Modena and Reggio Emilia
(Via Campi 183 ± 41125 Modena - Italy).
[email protected]
Evaluation of anti-Listeria activity.
The presence of Listeria monocytogens in fermented sausages is an increasing problem in the
sausages industry, because is usually present in raw material. Despite of the regular production processes
of sausages reduce the concentration of L. monocytogens, due to the formation of lactic acid by lactic acid
bacteria (LAB), the pH-drop and the drying out, a considerable number of this pathogenic microorganism
could survive (1). This may cause recurrent safety problems in the sausages with relatively high water
activity at the end of the ripening period and when the pH has only been slightly lowered by fermentation.
The strain Lactobacillus delbrueckii MB386, previously selected for the anti-listeria activity on
agar-plate and two other commercial LAB-based starters, B-LC-20 and B-SF-43, were evaluated in a
challenge test. The tested strains were singly applied (5x106 CFU/g) to a southern European sausage
recipe, together with the normal starter cultures containing Lactobacillus sakei (5x106 CFU/g) and
Staphylococcus xylosus (5x106 CFU/g) cells. A cocktail of 5 different strains of L. monocytogenes was
added to the batter (approx. 5x103 CFU/g). The challenge test was performed simulating only the
fermentation phase of a standard ripening: the batter meat stocks were collected in sealed jars and
incubated at 20°C for 72h, monitoring continuously the pH. At the initial time and every 24h the content
of L. monocytogenes, total LAB, and micrococcaceae were analysed by plate counting on ALOA, MRS,
and MSA media, respectively. LAB and micrococcaceae profile were similar in all batches. During the 3
days fermentation, Listeria decreased by 0.2 log units in control preparations without any anti-listeria
starter. In the batches containing anti-Listeria starter Listeria decreased on average by 0.8 log units. Both
of the commercial strains BLC-20 and BSF-43 caused L. monocytogenes to decrease by 1.0 log units; L.
delbrueckii MB386 showed a reduction of only 0.6 log units and was the less efficient strain.
Probiotic exploitation of meat starter lactic acid bacteria strains.
A probiotic is a living microorganism, mainly lactic acid bacteria (LAB) or Bifidobacteria, which
beneficially affects the health of the host when ingested in sufficient quantities. In this work, LAB starter
strains, selected on the base of their ability to ferment meat products, were evaluated in order to be
classified and exploited also as probiotics. The survival of bacteria in gastric juice depends on their
ability to tolerate pH low value. Due to excreted HCL, gastric pH is approx. 0.9, the presence of food may
raise the pH above 3. After the ingestion of food it takes approximately 3 h for the stomach to empty. Bile
salts are synthesized from cholesterol in the liver, stored in the gall bladder, and released into the small
intestine after ingestion of fatty meal. This detergent is critical to microorganisms since their cell
membranes are composed of polar lipids.
The survival of 25 Lactobacillus sakei under conditions similar to those in the gastro-intestinal
tract was determined (2). The acid resistance was evaluated measuring the survival in phosphate-buffered
saline at pH 3.5 and 37 °C after 1 h of incubation. The most resistant strains were L. sakei WC0237, L.
sakei WC0218, and L. sakei WC0234. In order to investigate bile salt tolerance the strains were incubated
for 6 h at 37 °C in MRSO medium, consisting of MRS medium supplemented with bile salts (Oxgall) at
the concentration of 0.15% and 0.30 % (w/v). The strains characterized by the higher tolerance were L.
sakei WC0246, L. sakei WC0247, and L. sakei WC0263.
(1) Työppönen, S.; Petäjä, E.; Mattila-Sandholm, T. Int. J. Food Microbiol. 2003, 83(3), 233-244.
(2) Ruiz-Moyano, S.; Martin A.; Benito M.J.; Nevado F.P.; Cordoba M.G. Meat science 2008, 80, 715-721.
72
P 53
Biotransformations in synthesis of Profens and development of a
new immobilized His Tag Horse Liver Alcohol Dehydrogenase
Matteo Poria, Paola Gallettia , Daniela Quagliab, Francesca Paradisib and Daria Giacomini.a
a
b
'HSDUWPHQWRI&KHPLVWU\³*&LDPLFLDQ´ University of Bologna, Italy
UCD School of Chemistry and Chemical Biology, University College Dublin, Belfield, Dublin 4, Ireland
[email protected]
Alcohol dehydrogenases are enzymes involved in natural oxidoreductive interconversions between
alcohols and aldehydes. In particular Horse Liver Alcohol Dehydrogenase (HLADH) is an interesting
enzyme and it has been used in several chemical processes.
In a research project on the development of a chemoenzymatic synthesis of Profens we used HLADH for
the asymmetric reduction of several racemic 2-arylpropanals to (2S)-arylpropanols.1,2,3,4 Optimized
reaction conditions in buffer±organic medium allowed the occurrence of a dynamic kinetic resolution
(DKR) process (Fig. 1).2 A DKR process combines a resolution of a racemic mixture with an in situ
racemization of the unreacted enantiomer and it is an effective method to overcome the limitation of a
50% maximum yield of a kinetic resolution. The DKR process with HLADH worked very well on
aldehydes precursors of important pharmaceutical leads.
H
HLADH
buffer / organic solvent
(S)
OH
(R,S)
R
TEMPO
NaClO, NaClO2
O
NADH
O
NAD+
OH
R
OH
(S)
R
O
yields up to 99%
yields up to 99%
(S)/(R) up to 99:1
(S)/(R) up to 99:1
In a collaboration with the University College of Dublin, we are developing a project on the
immobilization of HLADH. Enzyme immobilization is an important goal that allows for an easy recovery
of the enzyme from the reaction mixture and its reutilization with the final aim of allowing for the scale
up of chemoenzymatic processes to industrial scale.
To pursue this goal HLADH has been engineered with recombinant methodologies to insert a
polyhistidine tail (His-Tag) on the N-terminus. His-tagged HLADH resulted easier to purify and the Histails offered a valid support for selective immobilization onto a special solid support. Our preliminary
results on activity and selectivity of the immobilized His-Tagged HLADH (compared with the
commercial HLADH) on the bioreduction of racemic 2-aryl propanals showed an enhanced
enantioselectivity for (S)-aldehydes and no significant loss of activity. Moreover the enzyme can been
recycled six times before showing loss of activity.
To fulfil the synthesis of Profens starting from (2S)-arylpropanols an oxidation is required and we then
applied an efficient protocol with TEMPO, NaClO, and NaClO23, obtaining (S)-Profens without
racemization. We are now studying a biocatalityc approach for the oxidation step by laccases.
(1) Giacomini, D.; Galletti, P.; Quintavalla, A.; Gucciardo, G.; Paradisi, F. Chem. Commun. 2007, 4038- 4040.
(2) Galletti, P.; Emer, E.; Gucciardo, G.; Quintavalla, A.; Pori, M.; Giacomini, D.; Org. Biomol. Chem., 2010, 8, 4117-4123;
(3) Galletti, P.; Pori, M., Giacomini, D. SynLett 2010, 17, 2644-2648;
(4) Giacomini, D.; Cainelli, G.; Galletti, P.; Gucciardo, G.; Quintavalla, A.. Enzymatic process for the preparation of chiral 2-arylproprionic alcohols. PCT Int
Appl. (2008), PIXXD2 WO 2008074717 A2 20080626
73
P 54
Quinones bearing non-steroidal anti-inflammatory fragments as multitarget ligands
for Alzheimer¶V disease treatment
1,2
F. Prati, 1M. Bartolini, 1V. Andrisano, 1M.L. Bolognesi
1
Department of Pharmacy and Biotechonologies, University of Bologna,
Via Belmeloro 6, 40126 Bologna, Italy
2
Department of Drug Discovery and Development, Italian Institute of Tecnology,
via Morego 30, 16163 Genova, Italy
[email protected]
Memoquin is a drug candidate with a multitarget profile DJDLQVW$O]KHLPHU¶VGLVHDVH$' (1). It is a freeradical scavenger and an inhibitor of acetylcholine esterase enzyme (AChE) and amyloid-ȕ (Aȕ)
aggregation. The 2,5-diamino-benzoquinone scaffold of memoquin has been deemed to have a crucial
role in conferring the multiple activities (2). On these bases, a new series of memoquin derivatives was
designed and synthesized by linking the 2,5-diamino-benzoquinone core with several non-steroidal antiinflammatory drugs (NSAIDs), such as ibuprofen, sulindac, indomethacin, diclofenac and flurbiprofen. In
fact, epidemiological evidences indicate that NSAIDs may lower the risk of developing AD (3).
Furthermore, these drugs have been shown to reduce inflammation in the AD brain tissue and directly
affect the production of Aȕ (4).
The current series of compounds was initially tested against a number of isolated AD-related targets,
namely, human AChE and butyrylcholinesterase (BuChE), and Aȕ aggregation. The most active
inhibitors were further tested in primary chicken telencephalon neurons to assess their effect of on
secretion of Aȕ38, Aȕ40 and Aȕ42. Interestingly, some tested compounds turned out to be strong
inhibitors of Aȕ aggregation and displayed an attractive multipotent profile.
PPIs privileged structure
Memoquin
Ibuprofen
Indomethacin
Sulindac
Diclofenac
Flurbiprofen
(1) CAVALLI, A.; BOLOGNESI, M.L.; CAPSONI, S.; ANDRISANO, V.; BARTOLINI,M.; MARGOTTI, E.; CATTANEO,
A.; RECANATINI, M.; MELCHIORRE, C. Angew. Chem., Int. Ed. 2007, 46, 3689-3692.
(2) BOLOGNESI, M.L.; CHIRIANO, G.; BARTOLINI, M.; MANCINI, F.; BOTTEGONI, G.; MAESTRI ,V.;
CZVITKOVICH, S.; WINDISCH, M.; CAVALLI, A.; MINARINI, A.; ROSINI, M.; TUMIATTI, V.; ANDRISANO ,V.;
MELCHIORRE, C. J Med Chem. 2011, 54(24),8299-8304.
(3) VELD, B.A.; RUITENBERG, A.; HOFMAN, A.; LAUNER, L.J.; VAN DUIJN, C.M.; STIJNEN, T.; BRETELER,
M.M.B.; STRICKER, B.H.C. N. Engl. J. Med. 2001, 345(21), 1515-1521.
(4) WEGGEN, S.; ERIKSEN, J.L.; DAS, P. Nat. 2001, 414(6860), 212-216.
74
P 55
Development of advanced chromatographic methods for a complete phytochemical
characterization of raw propolis polyphenols and volatile compounds
F.P. Prencipe, F. Pellati, S. Benvenuti
Department of Life Sciences, University of Modena and Reggio Emilia, Via G. Campi 183, 41125
Modena
[email protected]
Propolis, or bee glue, is a dark-colored resinous substance collected by honeybees (Apis mellifera L.)
from several tree species. Because of its biological and pharmacological properties, such as antibacterial,
antiviral, antifungal, anticancer, anti-inflammatory, and immunomodulatory activities (1,2), propolis has
attracted researchers’ interest in the last decades. Since propolis is used extensively, a rapid and efficient
method for the extraction and analysis of propolis is certainly very useful.
With the aim to determine polyphenols in propolis we have applied RP-HPLC coupled with DAD and
MS detection, using the new fused-core column technology, which allowed a sensitive reduction in the
total analysis time in comparison with conventional particulate stationary phases (3). The HPLC analyses
were carried out on an Ascentis Express C18 column (150 mm × 3.0 mm I.D., 2.7 μm), with a mobile
phase composed by 0.1% aqueous formic acid and acetonitrile, under gradient elution. Different
extraction methods were compared, including sonication and microwave extraction, in order to obtain a
high recovery of polyphenols from raw propolis.
The other active component of propolis includes volatile compounds and its analysis was performed by
GC coupled with MS detection. A suitable HS-SPME extraction procedure, whose experimental
parameters were properly optimized, was developed using a 1 cm PDMS fiber. The GC analyses were
carried out on an HP-5 MS cross-linked 5% diphenyl-95% dimethyl polysiloxane capillary column (30 m
× 0.25 mm I.D., 1.00 μm film thickness), under programmed-temperature elution. The volatile
compounds extracted from raw propolis were identified by comparing the MS fragmentation patterns with
those of pure compounds and by mass spectrum database search using NIST.
The chromatographic methods developed in this study were applied to samples of raw propolis collected
in different Italian regions and allowed us to determine their metabolite fingerprinting, thus providing
new and reliable tools for the complete phytochemical characterization of this material.
(1) J. M. Sforcin, V. Bankova; Propolis: Is there a potential for the development of new drugs? J. Ethnopharmacol. 2011, 133,
253-260;
(2) M. A. R. Araujo, S. A. Libério, R. N. M. Guerra, M. N. S. Ribeiro, F. R. F. Nascimento; Mechanisms of action underlying
the anti-inflammatory and immunomodulatory effects of propolis: a brief review. Braz. J. Pharmacogn. 2012, 22, 208-219;
(3) F. Pellati, G. Orlandini, D. Pinetti, S. Benvenuti; HPLC-DAD and HPLC-ESI-MS/MS methods for metabolite profiling of
propolis extracts. J. Pharm. Biomed. Anal. 2011, 55, 934-948.
75
P 56
Comparative determination of carotenoids
in fresh vegetables, processed products and dietary supplements
1,2
Michele Protti, 2,3Roberto Mandrioli, 2Elisa Ghetti 1,2Laura Mercolini, 1Maria Augusta Raggi
1
Laboratory of Pharmaco-Toxicological Analysis, Department of Pharmacy and BioTechnology,
Alma Mater Studiorum - University of Bologna, Via Belmeloro 6, 40126 Bologna, Italy.
2
Inter-Department Centre for Industrial Research ± Advanced Mechanics and Materials (CIRI-MAM),
Operating Unit 6 ± Advanced Fashion Materials, Piazza Malatesta 29-30, 47923 Rimini, Italy
3
Department of Life Quality Sciences, Alma Mater Studiorum - University of Bologna,
Via Dei Mille 39, 4791 Rimini, Italy.
[email protected]
Fruits and vegetables constitute the major sources of carotenoid in human diet. They are present as microcomponents in fruits and vegetables and are responsible for their yellow, orange and red colors.
Carotenoids are thought to be responsible for the beneficial nutraceutical properties some foods in
preventing human diseases including cardiovascular diseases, cancer and other chronic diseases (1) and in
recent years their antioxidant properties have been the major focus of the scientific research in this field
(2). Tomato and derived foods are rich in carotenoids such as ȕ-carotene, lutein, astaxanthin, zeaxanthin
and lycopene (Fig.1 a-e).
a
ȕ-carotene
b
lutein
c
astaxanthin
d
zeaxanthin
e
lycopene
Figure 1
Tomato, within the Mediterranean diet is often consumed after cooking, in the form of sauces and
included in complex foods, therefore it is important to evaluate the content of such carotenoids as a result
of different types of heat treatments, in order to assess any loss due to degradation. Sometimes, the above
mentioned treatments may result in an enhancement in the levels of the substances, as these may be
released from vegetal phytocomplexes which can limit the bioavailability. Therefore, in addition to
defining the varieties of vegetables with the highest levels of carotenoids, it is important to establish the
cooking methods and treatments which may allow to maintain food beneficial properties.
Aim of this study is the development of an HPLC-DAD method for the analysis of different carotenoids
in fresh tomato, in tomato sauces and in sauces subjected to further cooking under different conditions.
Carotenoid extraction is achieved by means of a liquid-liquid extraction, followed by a chromatographic
separation with a C18 stationary phase, using a methanol-based mobile phase.
Furthermore, this method has been applied for the quality control of some tomato-based dietary
supplements, in order to compare their properties with those of the fresh tomatoes.
The method is currently undergoing validation, but seems to be suitable for application to complex
vegetal matrices, such as raw and cooked tomato-based foodstuffs as well as dietary supplements
formulations, to test their nutraceutical power.
(1) Engelhard, Y.N.; Gazer, B.; Paran, E. Am. Heart J. 2006, 151, 100e1-100e6.
(2) 2]\UHN0%HNWDúR÷OX%*oO, K.; Güngör, N.; Apak, R. Anal. Chim. Acta. 2008, 630, 28-39.
76
P 57
DD-ARYLALKYL NITRILES AS PRECURSORS OF 2,2-DISUBSTITUTED EHYDROXY NITRILES viaTIN-KETENEIMINES
QIN WENLING,1LONG SHA 1, and PANUNZIO MAURO2
1
Dipartimento di ChimLFD³*&LDPLFLDQ´8QLYHUVLWD¶Gi Bologna
Via Selmi, 2 40126 Bologna
2
ISOF-&15'LSDUWLPHQWR'L&KLPLFD³*&LDPLFLDQ´
Via Selmi, 2 40126 Bologna.
[email protected]
Due to their broad range of applications, E-hydroxy nitriles play an important role in organic
chemistry.1Their synthesis is usually achieved by reaction of a metallated nitriles and an aldehyde or a
ketones.2 As base sodium amide in liquid ammonia, butyl lithium, LDA have been used. The main
drawback of this aldol type reaction liesinto the possibility of a retro reaction, generally catalysed by a
base,giving rise to the starting materials.3 As a matter of fact, although the main driving force in such
carbonyl addition reaction of carbanions is considered to be the formation of a weaker base or nuclephile,
an additional driving force can arise from the counter cation of the forming alkoxy derivatives. In a
general program on the synthesis and use of metallo-ketene imines4,5 in organic synthesis, we would
report our studies on bypassthis drawback by using neutral tin-ketene imines as nucleophiles. The starting
materials have been chosen in such a way to afford, as final product, highly functionalized E-hydroxy
nitriles, potential parents of DD-disubstitutedcarbosugars (Scheme1).
CHO
O
N
C
Ar
Ar
Ar
O
Ar
Ar LDA
Ar
Ar
CHO
OH
CH2OH
C
+
N
OSn(R)3
C C N
R3SnCl Ar
OH
Ar
Ar
Sn(R)3
CHO
Ar
Ar
OH
OH
CH2OH
Ar
Ar
+
N
C
OSn(R)3
O
O
O
O
Buffer
N
Ar
Ar
C
OH
+
N
C
OH
O
O
O
O
Scheme 1
(1)
Nowill, R. W.; Patel, T. J.; Beasley, D. L.; Alvarez, J. A.; Jackson, E.; Hizer, T. J.;
Ghiviriga, I.; Mateer, S. C.; Feske, B. D. Tetrahedron Lett.2011, 52, 2440 and Refs therein cited.
(2)
Carlier, P. R.; Lo, K. M.; Lo, M. M. C.; Williams, I. D. The J. Org. Chem.1995, 60, 7511.
(3)
Kaiser, E. M.; Hauser, C. R. J. Am. Chem. Soc.1967, 89, 4566.
(4)
Denmark, S. E.; Wilson, T. W. Angew. Chem. Int. Ed.2012, 51, 9980.
(5)
Qin, W. L.; Long, S.; Panunzio, M.; Bongini, A. Synthesis. 2012, 44, 3191.
77
P 58
Effects of ocean acidification on calcifying marine organisms
1
Michela Reggi, 1Luca Sabbioni, 2Stefano Goffredo, 1Giuseppe Falini
1
'LSDUWLPHQWRGL&KLPLFD³*LDFRPR&LDPLFLDQ´, Alma Mater Studiorum - Università di
Bologna
2
Dipartimento di Scienze Biologiche, Geologiche e Ambientali, Alma Mater Studiorum Università di Bologna
[email protected]
The role of environmental parameters, such as temperature and pH, on the mineralogy of calcifying
marine organisms is a theme of increasing interest [1]. This because in the next century, due to the effect
of the increasing concentration of carbon dioxide in the atmosphere, a decrease of the pH and an increase
of the temperature of sea water is expected. The island of Panarea consists of a volcanic structure that has
evolved in recent geological times characterized by continuous and localized cold CO2 emissions creating
a natural pH gradient stable through time [2]. The pH gradient changed between 8.2, in normal sea water
far from the crater center, and 6.6, in the middle of crater where there is the biggest CO2 emission. Along
these gradient different calcifying organisms live: Balanophyllia europaea is a solitary zooxanthellate
scleractinian coral, endemic of the Mediterranean Sea; vermetids are sea snails, marine gastropod
molluscs; Padina pavonica and Acetabularia acetabulum are two macroalgae. All these species produce
calcium carbonate.
The aim of this work is to understand if the increase of acidification influences the different mineral
structure of this organism. The organisms were collected in four different site. These site were chosen
along the gradient with different pH values (7.6, 7.8, 8.0, 8.2). These pH values correspond to those
provided by Intergovernmental Panel on Climate Change (IPCC) for the next 100 years [3]. The shape
and the composition of the mineral structure were studied using X-ray diffraction, infrared spectroscopy,
electron microscopy, and thermogravimetric techniques.
Figure 1. SEM image of site 4 Acetabularia acetabulum surface.
(1) Ries JB, J. Exp. Mar. Biol. Ecol. 2011, 403, 54 -64.
(2) Aliani S, Bortoluzzi G, Caramanna G, Raffa F , Continental Shelf Research 2010, 30, 1338-1348
(3) Caldeira K, Oceanography 2007, 20, 288-295
78
P 59
Mathematical chromatography approach and multivariate analysis for food
traceability problems.
1
1
Marina Cocchi, 3Anna de Juan, 1Andrea Marchetti, 2Federico Marini, 12Elisa Salvatore.
University of Modena and Reggio Emilia, Department of Chemical and Geological Science.
2
University of Rome ‘Sapienza’, Department of Chemistry.
3
University of Barcelona, Department of Analytical Chemistry.
[email protected]
The need for accurate and reliable methods for the geographical traceability of foodstuff is becoming a
more and more important issue in the alimentary field, where the provenience of P.D.O. certified
products, guaranteed and declared by the producers, must be checked by the control authorities.
Nowadays, these authentication procedures are very rarely supported by reliable methods able to assure
that what is declared corresponds to truth. Recently chemometrics gave an incentive in the development
of methods able to single out chemical profiles related to the origin, so that some widespread and
economic analytical techniques have been revaluated thanks to the fine information obtained by
multivariate analysis of the collected data. In this work, attention is focused on Lambrusco, a wine typical
of the Modena district and, in particular, the possibility of characterizing its different varieties based on
the HPLC-DAD determination of the phenolic compounds is studied; to this purpose, samples coming
from the Modena area and extraterritorial were analyzed. In developing the instrumental procedure, the
reduction of the analysis time was prioritized at the expense of resolution, since co-eluted peaks, which
occur, were deconvolved ‘a posteriori’. As a consequence, the rapid chromatographic run allowed to
collect a higher number of samples, and hence to building a larger and more representative dataset, in a
shorter time.
Multivariate curve resolution was performed separately on the different multisets, one for each identified
peak cluster, to resolve and quantify the species of interest. In particular, the entire chromatographic run
was divided in several elution windows according to the position of the phenolic compounds. MCR-ALS
allowed the complete resolution of all coeluting peaks in the chromatographic landscapes, providing the
concentration profiles (C) and the spectral profile (ST) - carrying, respectively, quantitative and
qualitative information - for both analytes and interferents (1,2). Where it was possible to identify species
and standard were available, univariate calibration was performed and the absolute concentrations of the
analytes in all the samples were determined.
Anyway MCR resolution gives relative quantitative information (peak areas) for all the components in the
different multisets; these variables representing the fingerprinting information of each sample have been
afterwards subjected to multivariate analysis, using PCA for data exploration and PLS-DA to built
classification models for authenticity. A good discrimination of the wine varieties was obtained and the
model also revealed the most relevant polyphenols to solve this classification problem.
(1) Tauler R.; Chem. Intell. Lab. Sys., 1995, 30, 133.
(2) de Juan A., Tauler R.; Anal. Chim. Acta., 2003, 500, 195.
79
P 60
Small molecules modulating protein-protein interaction at the human thymidylate
synthase homodimer interface.
1
Susan Sammak, 1Glauco Ponterini, 1Rosaria Luciani, 1Matteo Santucci, 2Gabriele Cruciani, 2Emanuele
Carosati, 1Luca Costantino, 1Maria Paola Costi.
1
Dipartimento di Scienze della vita, Università di Modena e Reggio Emilia, Via Campi 183, 41100
Modena (Italy).
2
Dipartimento di Chimica, Via Erice di Sotto 8, 06123 Perugia (Italy).
[email protected]
Thymidylate synthase (TS), a homodymeric enzyme with two active sites, each formed by aminoacid side
chains belonging to both the monomers, catalyzes the methylation of 2’-deoxyuridine-5’-monophosphate
(dUMP) to 2’-deoxythymidine-5’-monophosphate (dTMP) using 5,10-methylenetetrahydrofolate as the
one-carbon methyl donor. dTMP is then phosphorylated by two successive steps to 2’-deoxythymidine5’-triphosphate (dTTP), an essential precursor for DNA synthesis. This pathway is the sole intracellular
de novo source of dTTP; therefore, human TS (hTS) represents a critical target in cancer chemotherapy,
and compounds able to inhibit the enzyme are clinically available [1]. This protein is also able, in its
monomeric form, to exert a non-catalytic role, being able to act as a regulatory protein by the interaction
with its own mRNA, thus regulating its expression through a feedback mechanism and with other RNA
sequences regulating the expression of proteins involved in apoptosis such as bcl2, cmyc and p53 [2].
All the TS inhibitors presently used in chemotherapy are either substrate or cofactor analogues and bind
to and stabilize the hTS active conformation that, in turn, could not be able to bind mRNA [2]. It is
known that the protein domain for binding to regulatory sequences on TS mRNA is located at the
interface of the two monomers; the monomeric form does not show any catalytic activity but maintains
the regulatory functionality. Thus, it is important to identify compounds that bind at the hTS homodimer
interface, in order to destabilize the dimeric form of the enzyme, while maintaining its regulatory
efficiency [3].
A fragment-based discovery method, called “tethering”, has been
utilized in the literature to identify small molecules that can serve as
starting points for the design of protein-protein interaction inhibitors
[4]. Tethering was applied to identify fragment-like compounds able to
modify hTS monomer-monomer interactions. First, the hTS dimer
interface in the available enzyme crystal structures was examined to detect those residues suitable to be
mutated to cysteines, i.e. those residues in the proximity of interfacial crevices able to accommodate
small molecules or molecular fragments. At the same time, a library of disulphides was optimized in
silico and tested for tethering by means of MS. Two leads were thus discovered, able to destabilize hTS
homodymer, and their binding mode to the protein has been suggested by molecular modeling studies.
In the present research I was engaged into the synthesis of a series of compounds in order to explore
structure-activity relationships to obtain more active compounds and experimentally validate their
supposed binding mode (compound 1 and its derivatives of general formula A).
[1] Brandt D.S., Chu E. Oncol. Res. 1997, 9, 403-410.
[2] Chu E., Allegra C.J. BioEssay. 1996, 18, 191-198.
[3] Cardinale D., Guaitoli G., Tondi D., Luciani R., Henrich S., Salo-Ahen O.M.H., Ferrari S., Marverti G., Guerrieri D.,
Ligabue A., Frassineti C., Pozzi C., Mangani S., Fessas D., Guerrini R., Ponterini G., Wade R.C., Costi M.P. Proc. Natl. Acad.
Sci. USA. 2011, 108, E542-E549.
[4] Erlanson D.A., Ballinger M.D., Wells J.A., Tethering, in Fragment-based approaches in Drug Discovery (Jahnke W. and
Erlanson D.A. Eds.). Wiley-VCH, Weinheim. 2006, 285-310.
80
P 61
Probing gold nanoparticles/highly modified nucleosides interaction by capillary
electrophoresis
Elena Sarti, Valentina Bosi, Luisa Pasti
Department of Chemistry, University of Ferrara, v. L. Borsari 46, 44121 Ferrara
[email protected]
Nanoparticles (NPs) are being employed in many different fields such as drug carriers, imaging agents
and analytical probes, due to their unique physico-chemical properties. With the growing of
nanotechnology applications in research and industry, the release of nanomaterials into the environment
could increase; therefore, ecotoxicological effects of NPs are rising concerns. Investigations on
molecule/nanoparticle interactions play a key role in both the determination of NP’s biocompatibility for
various biomedical applications and for nanosafety evaluation (1). Moreover, these studies can also find
application in sample pre-treatment and pre-concentration, in such cases NPs are employed as adsorbent
material (2). The aim of the present work was to evaluate the interaction between modified nucleosides
and gold nanoparticles (AuNPs), and to investigate the applicability of these NPs in Solid-Phase NanoExtraction (SPNE) systems.
The application of AuNPs as adsorbent media is a rapidly expanding application because their inherent
properties make them a very promising tool. In fact, controlled fabrication in a wide dimensional range
(1–150 nm) with limited size dispersity has been established. Moreover, AuNP surface can adsorb
multiple targeting agents and/or therapeutics. Finally, the core in essence is non-toxic, biocompatible and
inert (3). The nucleoside/AuNP system was studied by using Capillary Electrophoresis (CE), since it has
been demonstrated that this technique is a powerful tool to investigate bio-physical and kinetic parameters
of interactions between nanoparticles and compounds with biological activity (proteins, nucleotides,
DNA, drugs, etc. ...). In particular, we examined the effectiveness of CE in measuring the affinity
between AuNPs and three highly modified nucleosides (Figure 1): this class of compounds includes a
large number of molecules obtained from parent nucleosides. The increased interest in the synthesis of
new modified nucleosides is linked to their pharmacological activity as antibiotic, antiviral and/or
antitumoral drugs.
A)
B)
C)
Figure 1: three nucleosides studied
From the experimental data, the adsorption isotherm was calculated: AuNPs showed an high saturation
capacity for nucleoside C).
Release experiments were carried out by varying both the buffer composition and the surfactant
concentration of the medium. A recovery in the range 100-110% for different concentration levels of
nucleoside C) was obtained. Therefore, by employing AuNPs as adsorbent mean in Solid Phase Nano
Extraction (SPNE), an enrichment factor of 7 was attained. Finally, by combining SPNE with sample
injection in Reversed Electrode Polarity Stacking Mode (REPSM) which leads to a sample preconcentration inside the capillary (4), an enrichment factor of about 50 was achieved. Furthermore,
AuNPs could be used in multiple adsorption/release experiments because, after total release of the
analyte, their adsorption capacity is fully maintained.
(1) Liwen Li, Qingxin Mu, Bin Zhang, Bing Yan, Analyst, 2010, 135, 1519–1530
(2) Huiyong Wang, Shenjiang Yu, Andres D. Campiglia, Analytical Biochemistry, 2009, 385, 249–256
(3) Bradley Duncan, Chaekyu Kim, Vincent M. Rotello, Journal of Controlled Release, 2010, 148, 122–127
(4) Kuei-Hua Lin, Tieh-Chi Chu, Fu-Ken Liu, Journal of Chromatography A, 2007, 1161, 314–321
81
P 62
Synthesis and activity of novel chalcone-based derivatives as potential inhibitors of
deubiquitinating enzymes
1
1
Alessandra Scotti, 1Claudio Trapella, 1Mauro Marastoni
Department of Chemistry and Pharmaceutical Sciences, Via Fossato di Mortara 17/19, University of
Ferrara, I-44100 Ferrara, Italy
[email protected]
Ubiquitin-tagged substrates are degraded by the 26S proteasome, which is a multisubunit complex
comprising a proteolytic 20S core particle capped by 19S regulatory particles (1,2). The approval of
bortezomib for the treatment of multiple myeloma validated the 20S core particle as an anticancer drug
target (3). Here we describe the synthesis and preliminary biological evaluation of a new series of small
molecules derived from b-AP15 as a previously unidentified class of proteasome inhibitor that abrogates
the deubiquitinating activity of the 19S regulatory particle (4). b-AP15 inhibited the activity of two 19S
regulatory-particle–associated deubiquitinases, ubiquitin C-terminal hydrolase 5 (UCHL5) and ubiquitinspecific peptidase 14 (USP14), resulting in accumulation of polyubiquitin. Treatment with b-AP15
inhibited tumor progression in four different in vivo solid tumor models and inhibited organ infiltration in
an acute myeloid leukemia model. These results show that the deubiquitinating activity of the 19S
regulatory particle is a new anticancer drug target.
Herein we describe the synthesis and biological activities of new series of α,β-unsatured carbonyl system
compounds retain C2 simmetry, bearing various amino acid (R) on the cyclopentenone or 4-piperidone.
The amino group of the 4-piperidone will be functionalized by substitute with different physico-chemical
properties (RI).
O
R
O
R
R
R
N
R'
Preliminary biological evaluation of the new derivatives was carried out to assess their capacity to inhibit
the trypsin-like, chymotrypsin-like and post-acidic activities of the proteasome and successively for the
activity against deubiquitinases (DUBs) in cell extracts.
(1) Rechsteiner, M., Hoffman, L. & Dubiel, W, J. Biol. Chem. 1993, 268, 6065-069.
(2) Chu- Ping et al, J. Biol. Chem. 1994, 269, 3539-3547.
(3) Adams, J. & Kauffman, M. Cancer Invest, 2004, 22, 304-311.
(4) Pedraig D’Arcy et al; Nature Medicine. 2011, 17, 1636-1640.
82
P 63
Study of cancer cells metabolism alterations by mapping
both glucose uptake and lactate release
1,2
Alice Soldà, 1,2Stefania Rapino, 1Pier Giuseppe Pelicci, 2Francesco Paolucci, 1Marco Giorgio
1
2
European Institute of Oncology (Campus IEO), Via Adamello 16, 20139 Milan, Italy
8QLYHUVLW\RI%RORJQD&KHPLVWU\'HSDUWPHQW³*&LDPLFLDQ´9LD6HOPL%RORJQD,WDO\
[email protected]
Most cells use glucose as a fuel source. Glucose is metabolized by glycolysis in a multi-step set of
reactions resulting in the creation of pyruvate. In typical normal cells, much of this pyruvate enters the
mitochondria where it is oxidized by the Krebs C\FOHWRJHQHUDWH$73WRPHHWWKHFHOO¶VHQHUJ\GHPDQGV
However, in cancer cells, much of the pyruvate from glycolysis is directed away from the mitochondria to
create lactate. Lactate production is typically restricted to anaerobic conditions nevertheless cancer cells
preferentially channel glucose towards lactate production even when oxygen is plentiful, a process termed
³DHURELFJ\FRO\VLV´RU Warburg Effect. (1)
The past decade has seen a growth in the application of biosensors to micro and nano-meter level
investigations in a wide variety of disciplines. Rapid development, both in miniaturization techniques and
in understanding of biological processes, has accelerated the expansion of biosensors in clinical
applications. Enzyme-based sensors are very interesting because they offer high selectivity toward a
single analyte, based on their structural complementarities, and the opportunity to improve sensitivity,
time scale and information content. Furthermore, they are irreplaceable tools for non- invasive study of
glycolytic switching (or metabolism alterations) at cellular level. (2,3)
Enzyme-based ultramicroelectrode (UME) in conjunction with scanning electrochemical microscopy
(SECM) can be developed as a useful technique for studying cell metabolic fluxes, since it can map
electrochemical activity across the entire surface of a single cell and can record dynamic changes,
examining the metabolic differences between nonmetastatic and metastatic human cells. (2) Indeed it was
demonstrated that under aerobic conditions, cancer cells metabolize approximately tenfold, more glucose
to lactate in a given time than normal cells. (1)
Information about the way a cell performs glycolysis could be acquired by using modified UME
biosensor with glucose oxidase (GOx) and lactate oxidase (LOx) in combination with SECM.
The glucose and lactate amperometric sensors for SECM that we employ are homemade electrodes based
on a Pt 10 Pm substrate that is in contact with a polymer containing the specific enzyme (GOx or LOx)
(Scheme 1); glucose or lactate are measured indirectly at the electrode surface by amperometric oxidation
of hydrogen peroxide, that is formed in aqueous systems during the reaction catalyzed by the enzyme
entrapped in the matrix, involving the analyte of interest in aerobic conditions.
Scheme 1. Enzyme-based biosensor mechanism
This apparatus increases the spatial and time resolution of metabolic study, that will be used as powerful
tools for studying the altered processes that affect cancerous cells by mapping both glucose uptake and
lactate release.
(1) Koppenol, W. H.; Bounds, P. L.; Dang, C. V. Nature Reviews Cancer. 2011, 11, 325-337.
(2) Wilburn, J. P.; Cliffel D. E. Anal. Chem. 2008, 80, 2717-2727.
(3) Kurzawa C.; Hengstenberg, A.; Schuhmann, W. Anal. Chem. 2002, 74, 355-361.
83
P 64
Synthesis of new enzimatic inhibitors based on Dȕ-lactam structure
Roberto Soldati, Paola Galletti, Matteo Pori, Daria Giacomini
'HSDUWPHQWRI&KHPLVWU\³*&LDPLFLDQ´8QLYHUVLW\RI%RORJQD,WDO\
[email protected]
E-LDFWDP FRPSRXQGV DUH UHDOO\ ³HYHUJUHHQ´ PROHFXOHV Beside bicyclic E-lactam substrates such as
penicillins, cephalosporins, and carbapenems, monocyclic compounds (azetidinones) emerged for their
interesting and variegated biological activities.1 For instance, 4-alkyliden-azetidinones proved to be
interesting scaffolds for antibiotics against resistant bacteria2 and effective enzymatic inhibitors against
Human Leukocyte Elastase (HLE) and matrix metallo-proteases (MMPs), and as antiaggregating agents.3
Moreover, our interest in the design of new ȕ-lactam compounds with specific biological activities
recently allowed us to extend our strategies to the synthesis of new monocyclic derivatives with specific
inhibitory potency against integrins and histone deacetylase enzymes (HDAC).4
Furthermore, we recently developed the synthesis of new E-lactam peptides specifically designed as
integrin inhibitors, which should work as mimetic of the RGD (Arg-Gly-Asp) peptide. The study of
integrin inhibitors is generally devoted to the design and development of structures able to mimic the
RGD sequence, key portion in the recognition process of proper integrin ligands.5 Our optimized strategy
involved the use of the commercially available 4-acetoxy-azetidin-2-one as starting material, and
efficiently allowed specific modifications at both C-4 and nitrogen atom of the E-lactam ring (Figure 1).
Figure 1
(1) Galletti, P.; Giacomini, P.; Curr. Med. Chem., 2011, 18, 4265-4283.
(2) Broccolo, F.; Cainelli, G.; Caltabiano, G.; Cocuzza, C. E A.; Fortuna, C. G.; Galletti, P.; Giacomini, D.; Musumarra, G.;
Musumeci, R.; Quintavalla, A.; J. Med. Chem., 2006, 49, 2804-2811.
(3) Cainelli,G.; Galletti, P.; Garbisa, S.; Giacomini, D.; Sartor, L.; Quintavalla, A.; Bioorg. Med. Chem., 2005, 13, 6120-6132.
'HOO¶$LFD,6DUWRUL.; Galletti, P.; Giacomini, D.; Quintavalla, A.; Calabrese, F.; Giacometti, C.; Brunetta, E.; Piazza, F.;
Agostini, C.; Garbisa, S.; J. Pharmacol. Exp. Ther., 2006, 316, 539-546.
Cainelli, G.; Angeloni, C.; Cervellati, R.; Galletti, P.; Giacomini, D.; Hrelia, S.; Sinisi R.; Chem. Biodivers., 2008, 5, 811829.
(4) Galletti, P.; Quintavalla, A.; Ventrici, C.; Giannini, G.; Cabri, W.; Penco, S.; Gallo, G.; Vincenti, S.; Giacomini, D.;
ChemMedChem, 2009, 4, 1991-2001.
Galletti, P.; Quintavalla, A.; Ventrici, C.; Giannini, G.; Cabri, W.; Giacomini, D.; New J. Chem., 2010, 34, 2861-2866.
(5) Plow, E. F.; Haas, T. A.; Zhang, L.; Luftus, J.; Smith, J. W.; J. Biol. Chem., 2000, 275, 21785-21788.
84
P 65
First Synthesis of phosphonamidoboronic acid as β-lactamase inhibitors
E. Speri, a C. Romagnoli, a O. Eidam, b E. Prevedelli, a B. K. Shoichet b and F. Prati a
a
Dipartimento di Scienze della Vita, Università di Modena e Reggio Emilia, Via Campi 183, 41125 (MO)
b
Department of Pharmaceutical Chemistry, University of California, San Francisco (USA)
[email protected]
β-lactamases are well known enzymes produced by bacteria to inactivate β-lactam antibiotics. Boronic
acids are able to counteract these enzymes and to restore antibiotic activity, acting as transition-state
analog inhibitors. Moving from our previous findings on carboxamide and sulfonamide boronic acids as
efficient β-lactamase inhibitors, (1,2) we here describe the effect of the replacement of these groups with a
phosphonamide. The synthesis of phosphonamidomethaneboronate A, B and C was achieved in an
efficient one-pot procedure starting from the appropriate phosphonic dichloride, subsequently allowed to
react with the selected alcohol and the aminomethaneboronate moiety.
Kinetic data on AmpC β-lactamase inhibition displayed in case of phosphonamide A and B a 5-fold
improved activity with respect to the corresponding carboxamide; conversely, in case of phosphonamide
C a 400-fold lower activity was observed, suggesting for this new class of derivatives a change in
structure activity relationship (SAR).
O CH3
P O
HN
O
A
B
O
O
P Cl
Cl
O
P O
HN
O
B
CH3
O
B
O
H3C P Cl
Cl
O
O P CH3
HN
O
B
O
C
Crystallographic structures of the inhibitors in complex with AmpC to rationalize the SAR and to provide
useful information for further design will be performed.
(1)
Morandi, F.; Caselli, E.; Morandi, S.; Focia, P. J.; Blazquez, J.; Shoichet, B. K.; Prati, F. Nanomolar inhibitors of
AmpC beta-lactamase. J. Am. Chem. Soc,. 2003, 125, 685-95.
(2)
Eidam, O.; Romagnoli, C.; Caselli, E.; Karpiak, J.; Babaoglu, K.; Teotico Pohlhaus, D.; Bonnet, R.; Shoichet, B. K.;
Prati, F. Design, synthesis, crystal structures and antimicrobial activity of sulfonamide boronic acids as beta-lactamase
inhibitors. J. Med. Chem., 2010, 53, 7852-7863.
85
P 66
STUDY ON PRIMARY METABOLISM OF BERBERINE IN HUMAN BY
CORRELATION BETWEEN PHYSICOCHEMICAL PROPERTIES AND
PLASMA
Silvia Spinozzi1, Carolina Colliva1, Cecilia Camborata1, Marinella Roberti2, Cristina Ianni2, Aldo
Roda1
1
2
Department of &KHPLVWU\³* CiamiciDQ´, Via Selmi 4, 40126, University of Bologna, Italy
Department of Pharmaceutical Sciences, University of Bologna, Via Belmeloro 6, 40126, Bologna, Italy
[email protected]
Berberine (BBR) is an isoquinoline alkaloid of the protoberberine type, usually found in the roots,
stems, rhizomes and bark of plants such as Berberis, Hydrastis, Coptis, etc, which is used in Chinese
traditional medicine as plant extracts and decoctions. Recent clinical trials showed the beneficial effects
of berberine in hypercholesterolemic patients. Indeed, administration of berberine decreased the levels of
total cholesterol, LDL-cholesterol and triglycerides by a dual mechanism of action: inhibition of the
synthesis of triglycerides and up-regulation of the activity on the low-density-lipoprotein receptor
(LDLR). Even though nutraceuticals do not require a conventional drug approval trial in term of
pharmacokinetics, metabolism and safety, their blood levels should be monitored to avoid undesired side
effects (i.e., ipertension in the case of berberine).
To better understand the overall pharmacokinetics and the structure-activity relationship the main
physico-chemical properties in aqueous solution have been evaluated including the lipophilicity
(LogPo/w), pKa, and the binding affinity with albumin of BBR and its main primary metabolites
(Berberrubine M1, Thalifendine M2, Demethyleneberberine M3, Jatrorrhizine M4, showed in Figure1) in
plasma.
A new method HPLC-ES-MS/MS, sufficiently sensible (LOQ=1.5nM) and selective, for the
identification and the quantification of berberine and its major metabolites in human plasma, has been
developed and validated according to current guidelines. This method was then applied both a
pharmacokinetic study in 10 healthy subjects after acute administration of 500 mg of berberine and a
biodistribution study after chronic administration of 15 mg/kg daily of berberine to 12
hypercholesterolemic subjects for three months.
The correlation between the lipophilicity, evaluated as 1-octanol/water partition coefficient (LogPo/w
pH=7.0 ), and pharmacokinetic studies (Cmax: BBR 0:11 ± 0.04 nM, M1 1:38 ± 0:32 nM, M3 0:14 ± 0.02
nM, M4 0.13 ± 0.02 nM) showed that berberine has an unusual metabolism where is produced a
metabolite, M1, even more lipophilic than active ingredient (BBR -1.19, M1 1.67, M3 -1.27, M4 -1.29).
The highest lipophilicity of M1 might be involved in a ketoenol tautomerism in physiologic environment
(pH range 8.5-4.5). Furthermore, the positive correlation between plasma levels and lipophilicity suggest
that M1, with the higher LogPo/w is present in higher concentration as a results of an efficient intestinal
absorption by passive diffusion and that M1 are potentially active like or even more than BBR.
86
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Thiyl Glycosylation of Propargylated Octasilsesquioxane: Synthesis and Lectin
Binding Properties of Densely Glycosylated Clusters on a Cubic Platform
Alberto Marra,[1][‡] Samuele Staderini,[1] Nathalie Berthet,[2] Pascal Dumy,[2][‡] Olivier Renaudet,[2] and
Alessandro Dondoni[1]
1
Dipartimento di Chimica, Laboratorio di Chimica Organica, Università di Ferrara,
Via L. Borsari 46, 44100 Ferrara, Italy
2
Département de Chimie Moléculaire, UMR CNRS 5250, Université Joseph Fourier,
570 Rue de la Chimie, BP 53, 38041 Grenoble cedex 9, France
[‡]
Current address: Ecole Nationale Supérieure de Chimie de Montpellier,
Equipe “Glycochimie et reconnaissance moléculaire”,
8 Rue de l’Ecole Normale, 34000 Montpellier, France
[email protected]
A new polyhedral oligomeric silsesquioxane (POSS) derivative possessing a periphery of eight
PEGylated chains functionalized with terminal propargyl groups was synthesized starting from the
commercially available octavinyl POSS (1). The photoinduced free-radical coupling of this octapropargyl
POSS derivative with various sugar thiols enabled the preparation of globular hexadecavalent
glycoclusters. The affinities of some selected densely glycosylated clusters toward specific lectins were
measured by the Enzyme-Linked Lectin Assay (ELLA). Thus, the binding selectivity toward
Concanavalin A displayed by the hexadecavalent mannosylated and glucosylated clusters was much
higher than the selectivity observed for the corresponding octavalent glycoclusters (2). Moreover, the
affinity of the N-acetylglucosamine-based cluster toward wheat germ agglutinin (WGA) revealed a
remarkable glycoside cluster effect with up to a 9.0 × 105-fold increase in binding as compared with the
monovalent GlcNAc. As a multivalent effect of the same order of magnitude was reported in the case of
the octavalent GlcNAc cluster toward the same lectin, it is concluded that increasing the number of sugar
units around the cubic platform does not lead systematically to an affinity enhancement. (3)
(1) M. Lo Conte, S. Staderini, A. Chambery, N. Berthet, P. Dumy, O. Renaudet, A. Marra, A. Dondoni, Org. Biomol. Chem
2012, 10, 3269-3277.
(2) M. Gomez-Garcia, J. M. Benito, R. Gutierrez-Gallego, A. Maestre, C. Ortiz Mellet, J. M. Garcia Fernandez, J. L Jiménez
Blanco, Org. Biomol. Chem. 2010, 8, 1849-1860.
(3) D. Deniaud, K. Julienne, S. G. Gouin,Org. Biomol. Chem. 2011, 9, 966-979.
87
P 68
Capture Compound Mass Spectrometry Technology: a novel tool for the study of
folatome and its perturbation by peptides that inhibit the thymidylate cycle in
ovarian cancer cells
1
1
Laura Taddia, 2Filippo Genovese, 1Glauco Ponterini, 3Alessandra Gualandi,
1
Monica Caselli and 1Maria Paola Costi
IG grant AIRC 2010, Drug Resistance in Ovarian Cancer
Dip. di Scienze della Vita, Università di Modena e Reggio Emilia, 41126 – Modena
2
CIGS, Università di Modena e Reggio Emilia, 41126 – Modena
3
CRBA, Policlinico S. Orsola-Malpighi, Università di Bologna – 40138 - Bologna
[email protected]
Ovarian cancer (OC) is the fifth most common cause of cancer death in women. The first-line treatment is
based on platinum-derivative drugs (DDP) but the therapy is often ineffective due to the emergence of
resistance (1). For over 50 years, folate-pathway-directed drugs have influenced treatments against
cancer, and the discovery of novel antifolate agents with improved properties and higher activities
represents an interesting strategy for the treatment of OC. Antifolate and antimetabolite drugs inhibit
proteins involved in folate pathways interfering with the metabolism of nucleotides (2). Recently our
group designed octapeptides able to inhibit the human thymidylate synthase (hTS) with an innovative
antitumor activity against sensitive and resistant OC cells (3). To better understand the mechanism of
action of these peptides, we adopted a proteomic approach (‘Capture Compound Mass Spectrometry
Technology’™, CCMS, Caprotec Bioanalytics), in order to understand how the treatment perturbs the
expression of proteins involved in the folate pathway.
CCMS is an enrichment system, able to capture folate-related proteins through a fishing-out molecular
device (Capture Compound) composed of three main functional units: i) methotrexate, a multitargeted
antifolate with affinity for many folate-related proteins, acts as a ‘bait’ for these proteins; ii) a
photoreactive unit enables covalent binding of the captured proteins to the active molecular device; iii) a
biotin unit fixes the device/captured proteins to streptavidin-coated magnetic beads for physical
separation from the unreacted cell lysate. This novel experimental tool allows for a reduction in the
complexity of biological samples and an enrichment of low expression proteins. The ability of selected
small peptides to modulate the expression of proteins involved in the folate pathway in model OC cell
lines will be assessed through CCMS followed by a semi-quantitative LC-MS/MS-based approach.
Acknowledgments: This work is supported by AIRC-DROC IG10474.
(1) Ozasa H, Oguri T, Hagner N, Joerger M. Cancer Manag Res. 2010, 19, 2.
(2) Wright DL, Anderson AC. Expert Opin Ther Pat. 2011, 21, 9.
(3) Cardinale D. et al. PNAS 2011, 108(34), E542-9.
88
P 69
Development and validation of new hybrid nanosystems PLGA/DOPE for an
intracellular delivery of therapeutics
1
P. Veratti, 1D. Belletti, 1G. Tosi, 1F. Forni, 1M.A. Vandelli, 2A. Grabrucker, 1B. Ruozi
1
2
Dip. Scienze della Vita, Università di Modena e Reggio Emilia, Italia
Institute for Anatomy and Cell Biology, Ulm University, Ulm, Germany
[email protected];[email protected]
In terms of delivery, drugs must be transported to their target sites (cellular but also subcellular target) to
exert their biological effects. Thus, a drug delivery system must overcome a series of extracellular and
intracellular barriers. Our research group focused on biocompatible and biodegradable poly(d,l-lactideco-glycolide) (PLGA) nanocarriers, engineered with different specific ligands able to promote the brain
targeting (1-2). Preliminary experiments highlighted that the plain PLGA nanoparticles (NPs) exploit
endocytosis-based mechanisms to enter into neuronal cells in vitro. These studies also demonstrated the
difficulty of these vectors to escape from the endo-lysosomal compartment, preventing the release of
active drugs in the cytoplasm or in the nucleus. As evident, to create nanovectors able to deliver
therapeutics in the site of action allowing them to be successfully active, beside the aim of targeting
specific cell populations, the nanocarriers must be able to escape from endo-lysosomal vesicles.
To this aim, we formulated new hybrid NPs through the W/O/W emulsion technique, mixing PLGA with
DOPE (1,2-dioleoyl-sn-glycero-3-phosphatidylethanolamine), a phospholipid widely used in liposome
formulation for gene therapy, thanks to its fusogenic activity (3-4). In order to identify the composition
with the best technological properties and the optimal escape ability, we tested different amounts of
DOPE added to the starting formulation (0.5, 2.5, 5, and 20% w/w). These new hybrid NPs were
characterized in their chemico-physical and technological properties, as .particle size, surface charge and
morphology, in comparison with PLGA NPs, showing no significant differences in terms of size but an
increased morphological complexity.
After purification, we dosed the rate of DOPE steady incorporated in the polymeric matrix of hybrid NPs,
evidencing that the maximum amount of DOPE which could be stably formulated in hybrid structures is
in the order of about 3 mg/100 mg of NPs.
Another critical parameter for nanoparticulate carriers is represented by their stability over storage and in
simulated physiological conditions. Thus, the stability of hybrid NPs was confirmed over time (at 4° for
30 days) and after incubation at 37 °C in biological fluids (stability in serum).
To evaluate their ability to escape from the endo-lysosomal compartment, the best formulation of the
hybrid NPs (namely 5% of DOPE) was tested in vitro on hippocampal neuronal cultures showing an
increased endosomal escape after transfection in comparison to PLGA NPs. These promising results
confirm the potential application of this strategy in the subcellular targeting of drugs.
(1) Grabrucker, A.M.; Garner, C.C.; Boeckers, T.M.; Bondioli, L.; Ruozi, B.; Forni, F.; Vandelli, M.A.; Tosi, G. PLoS
ONE. 2011, 6(3), e17851.
(2) Tosi, G.; Badiali, L.; Ruozi, B.; Vergoni, A.V.; Bondioli, L.; Ferrari, A.; Rivasi, F.; Forni, F.; Vandelli, M.A..
Nanomedicine, 2011, 7(3), 365-382.
(3) Kearns, M.D.; Patel, Y.N.; Savva, M. Chemistry and Physics of Lipids, 2010, 163(8), 755-764.
(4) Wasungu, L.; Hoekstra, D. Journal of Controlled Release, 2006, 116, 255–264.
89
P 70
An improved protocol for Yonemitsu-type trimolecular condensation
A. Tolomelli, L. Gentilucci, A.Viola1
1
'HSDUWPHQWRI&KHPLVWU\³*&LDPLFLDQ´8QLYHUVLW\RI%RORJQDVia Selmi 2, 40126 Bologna (Italy)
[email protected]
Multicomponent Reactions (MCRs) represent nowadays a novel and challenging frontier in
synthetic organic chemistry. In this kind of processes three or more components react in the same
vessel leading to the final product without the need of isolating any intermediates. Since the very
beginning of their validation and application, MCRs proved to be a very useful tool for the synthesis of
structurally complex molecules, in particular natural products, and in the field of drug discovery.1
CO2R2
R3
R3CHO
R4
+
N
CO2R2
R1
Yb(OTf)3
Base
MW/rt
MeCN
R5
R1
R4
N
R5
Fig.1 Yb(OTf)3 promoted Yonemitsu-type reaction
In the lecterature there are many exaples of Yonemitsu reactions employing as substrate malonic
derivatives but few whit acetoacetics. The known methods utilizing TiCl4 in molar ratio2, or Lewis acids
such as Yb(OTf)3 ultrasound assistend1 with long reaction time. We are able, through a microwave
assistance, to use catalytic amounts of Lewis acid and to reduce considerably the reaction times.
1)
F. Epifano, S. Genovese, O. Rosati, S. Tagliapietra, C. Pelucchini, M. Curini; Tetrehedron Lett., 52, 2011, 568-571.
2)
S. Gérard, A. Renzetti, B. Lefevre, A. Fontana, P. de Maria, J. Sapi;Tetrahedron, 66, 2010, 3065-3069.
90
P 71
Arginine analogues as potential active cardiovascular contrast agents in MRI
F. Zamberlan#, L. Lloyd§, S.B. Duckett§*, D.K. Dawson+, M.P. Frenneaux+*, M. Zanda+*
#
Department of Chemistry, University of Ferrara (Italy), §Department of Chemistry, University of York
(UK), +Institute of Medical Sciences, University of Aberdeen (UK).
Arginine is a substrate for NOS enzymes; the eNOS type is involved in the regulation of smooth muscle
relaxation and blood pressure. (1)
The sensitivity of both nuclear magnetic resonance spectroscopy and magnetic resonance imaging is very
low because the detected signal strength depends on the small population difference between spin states
even in high magnetic fields. Hyperpolarization methods can be used to increase this difference and
thereby enhance signal strength. (2)
Hyperpolarized arginine and its analogues could be a source of NMR signal, and therefore be used as
MRI active contrast agents for the early detection of cardiovascular diseases.
To achieve such polarization, a Non Hydrogenative ParaHydrogen Induced Polarization – NH-PHIP, the
SABRE approach (3) – has been tested on four samples with up to 17-fold NMR signal enhancements
and higher Signal to Noise Ratio compared to normal NMR scan.
The samples have been obtained by coupling arginine with four different pycolinic bases, and are
currently being tested as eNOS substrates/inhibitors.
Another PHIP technique, involving hydrogenation of a double C-C bond of different arginine analogues
with parahydrogen, (2) is also under investigation and the progress with the synthesis of the PHIP
arginine tracers will be discussed.
1. R.B. Silverman et al., Bioorganic and Medicinal Chemistry 1999, 7, 1097-1104
2. S.B. Duckett, C.J. Sleigh, Journal of Progress in Nuclear Magnetic Spectroscopy 1999, 34, 71-92
3. S.B. Duckett et al., Science 2009, 323, 1708-1711
91
P 72
Development of a device for ultrasensitive electrochemiluminescence microscopy
imaging based on carbon nanotubes electrodes
1
Martina Zangheri, 1Giovanni Valenti, 1Mara Mirasoli, 1Massimo Marcaccio, 2Sandra E. Sansaloni,
2
Alain Penicaud, 1Francesco Paolucci, 1Aldo Roda
1
Dipartimento di Chimica, Università di Bologna, via Selmi 2, 40126, Bologna, Italy
2
CNRS, Centre de Recherche Paul Pascal (CRPP), Pessac, France
[email protected]
Electrochemiluminescence (ECL) is widely used in biosensors and immunoassays thanks to the high
sensitivity and specificity of the electrochemically-triggered luminescence signal [1-4]. The peculiar
analytical performances in terms of high detectability of conventional chemiluminescence (CL) are
retained and, in addition, the electrochemical trigger of the reaction allows controlling the time and
position of light emission from ECL probes. These properties make ECL systems particularly attractive
also for microscopy imaging techniques in biological tissue sections or single cells, such as in situ
hybridization (ISH) and immunohystochemistry (IHC). Nevertheless, while CL detection has been
proposed for microscopy imaging providing good analytical performance [5-8], ECL has never been
exploited in such applications.
We have developed a transparent electrochemical cell on microscope
glass slide (Fig.1) for ECL imaging suitable for single cell analysis,
which allows acquiring both the transimetted light image (thanks to its
transparency) and the ECL-generated image. The cell, based on a
transparent conducting carbon nanotube (CNT) film, has a threeelectrode configuration. A dedicated instrument composed of a
microscope in a dark box equipped with an ultrasensitive nitrogencooled
charge
coupled
device
(CCD)
camera
and
a
potentiostat/galvanostat has been employed. The electrochemical cell
was optimized using 8-Pm diameter beads coated with a Ru(bpy)32+
Figura 1
complex in order to simulate fixed and labelled cells. ECL is generated
in an oxidative/reduction mechanism by the electrochemical oxidation
of Ru(bpy)32+ in the presence of a coreactant, tri-n-propylamine (TPA), to an active redox state via a
series of cyclic oxidation/reduction steps at the electrode surface by applying an electrical potential at the
working electrode. In a previous work a similar electrochemical cell using fluorine-doped tin oxide (FTO)
coated glass has been reported [9], which however suffered from poor reproducibility.
The CNT-based electrode material employed in this work is particularly interesting compared with FTO
because it yields very intense ECL signals at lower potential, owing its ability to catalyze TPA oxidation.
In addition, CNTs provide excellent conductivity and a nanostructured electrode surface, thus increasing
its active area.
Microscope imaging showed ECL signals that were detected only in correspondence to functionalized
beads present on the electrode surface, and the probe could be accurately localized. In perspective, the
ECL imaging device can be used in conjunction with other CL-based imaging methods for ultrasensitive
multiplex imaging on cells and tissue sections.
Lin J.;Ju H.; Biosens. Bioelectron. 2005, 20,1461-1470
Pittmann T. I., Thomson B.; Miao W.; Anal. Chim. Acta 2009, 632, 197-202.
Lu, Y.; Young, J.; Meng, Y. G. Curr. Opin. Pharmacol. 2007, 7 (5), 541±546
Bard, A. J.; Li, X.; Zhan, W. Biosens. Bioelectron. 2006, 22 (4), 461±472.
Roda, A.; Pasini, P.; Musiani, M.; Girotti, S.; Baraldini, M.; Carrea, G.; Suozzi A. Anal. Chem. 1996, 68, 1073±1080.
Roda, A.; Guardigli, M.; Pasini, P.; Musiani, M.; Baraldini, M. In Luminescence Biotechnology: Instruments and
Applications; Van Dyke, K., Van Dyke, C.,Woodfork, K. Eds.; CRC Press: Boca Raton, FL, 2002; 481-501.
(7) Bonvicini, F.; Mirasoli, M.; Gallinella, G.; Zerbini, M.; Musiani, M.; Roda, A. Analyst 2007, 132, 519±523.
(8) Guardigli, M.; Marangi, M.; Casanova, S.; Grigioni, W. F.; Roda, E.; Roda, A. J. Histochem. Cytochem. 2005, 53,
1451±1457.
(9) Dolci L. S.; Zanarini S., Della Ciana L.; Paolucci F.; Roda A.; Anal. Chem., 2009, 81, 6234-6241
(1)
(2)
(3)
(4)
(5)
(6)
92
P73
A NEW VERSATILE CLASS OF AZO-DERIVATIVES WITH MULTIPLE
APPLICATIONS IN MATERIALS CHEMISTRY
Nicola Zanna,a Carla Boga,a Luciano Forlani,a
a
Dipartimento di Chimica ,QGXVWULDOH ³7RVR 0RQWDQDUL´ $/0$ 0$7(5 678',2580 Università di Bologna, Facoltà di Chimica Industriale, Viale Risorgimento 4, 40136 Bologna,
Italia.
[email protected] unibo.it
)RUPDQ\\HDUVRXUUHVHDUFKJURXS¶VLQWHUHVWOLHVLQWKHVWXG\RIQXFOHRSKLOLFHOHFWURSKLOLFDURPDWLF
substitution reactions. We found that when strongly activated substrates are used for mechanistic
studies, the classical rules related to the steps involved in this kind of reactions are not always
followed, allowing us to identify, and in some cases to isolate, the related Wheland, Meisenheimer
or V-complexes that are contemporaneously Wheland and Meisenheimer intermediates.1a-c We also
found interesting behaviour of the reaction products derived from the coupling of these strongly
activated substrates. In the course of our mechanistic studies on the reaction between diazonium
salts and 2-aminothiazole derivatives (Scheme 1) we discovered, in some case in a serendipitous
way, some interesting properties of such coupling products.
Scheme 1. Formation of new azo-derivatives by reaction between diazonium salts and 2-aminothiazole
derivatives
Despite this was not the first target of our research, we start to investigate their peculiar behaviours.
For example we found that almost all products 3 have the ability to colour fibers such as cotton and
wool just by dispersing it in water at room temperature and let the fibers adsorb the dyes.
Another interesting properties is the ability of compounds 3 to act as a pH indicators, changing
colour in both acid and basic environment. At last, we found that all compounds 3 can form
nanoparticles (by using the reprecipitation method) which showed an intense fluorescence emission,
a property that make these compounds promising as probes for bioimaging.
1 a
Boga, C.; Del Vecchio, E.; Forlani, L. Eur. J. Org. Chem. 2004, 1567±1671; bBoga, C.; Del Vecchio, E.; Forlani, L.;
Mazzanti, A.; Todesco, P. E. Angew. Chem. Int. Ed. 2005, 44, 3285±3289; cForlani L.; Boga C.; Mazzanti A.; Zanna N.
Eur. J. Org. Chem., 2012, 1123±1129
93
P 74
Last minute abstract
Chiral Polythiophenes: a promising material
for the study of the Chiral Induced Spin Selectivity
1
Francesco Tassinari, 2Shinto Matthew , 1Francesca Parenti, 1Luisa Schenetti, 2Ron Naaman
1
University of Modena and Reggio Emilia, via Campi 221, 41125, Modena.
2
Weizmann Institute of Science, 234 Hertzl Street, 76100, Rehovot, Israel.
[email protected]
The synthesis of both the enantiomers of a cysteine substituted thiophene monomer is reported (1). Once polymerized these
molecules gave access to self assembling polythiophenes able to organize itself in chiral superstructures, controlled by the sign
of the cysteine chiral center. These polymers show an interesting behavior due to the inter-chains hydrogen bonding
interactions, that causes the formation of helical architectures in the solid state. The two polymers have been characterized both
in solution and in the solid state.
These chiral polymers have been used as spin filters to investigate the existence of the Chiral Induced Spin Selectivity effect
(2) in the microscale dimension. Micro- and nano-scale multilayered devices based on these chiral polythiophenes were
prepared using different techniques, and characterized with electrical measurements under applied magnetic field.
The alignment of the polymer chains in relation to the substrate surface has been deepened (3), since the orientation of the
helical aggregates in the film influences the magnitude of the spin filtering effect. Studies of the effect of a strong applied
electric field on the alignment of the polymer both in static and dynamic experiments were carried out, and the obtained films
were characterized with various surface analysis techniques.
(1) Mucci, A.; Parenti, F.; Schenetti, L. Macromolecular Rapid Communications. 2003, 24, 9, 547–550.
(2) Göhler, B.; V. Hamelbeck; T. Z. Markus; M. Kettner; G. F. Hanne; Z. Vager; R. Naaman; H. Zacharias. Science. 2011, 331,
6019, 894–897.
(3) Sugita, A.; Tasaka, S. Journal of Polymer Science Part B: Polymer Physics. 2004, 42, 24, 4433–4439
94