Les journées Très Grand Sud-Ouest (TGSO) de la Société Chimique

Les journées Très Grand Sud-Ouest (TGSO) de la Société Chimique de France, organisées à
Toulouse les 27 et 28 Novembre 2014, innovent pour cette 24ème édition en s’ouvrant sur
l’étranger avec l’invitation d’une délégation de trois conférenciers venant du Portugal.
Jeudi 27 Novembre 2014 à 16h45 : Conférence du Professeur Artur M. S. SILVA (Université
de Aveiro, [email protected]) :
« Exploring organocatalysis and carbohydrates as sources of chiral compounds »
Creation of C-C bonds remain one of the greatest challenges in organic synthesis, particularly in
the stereoselective construction of complex molecules. Organocatalysis has recently emerged as a
powerful tool to achieve this goal catalytically. Considerable efforts have been devoted to the
development of organocatalytic asymmetric Michael additions [1]. For example, our group has
achieved
the
1,4-conjugate
addition
(1,4-CA)
of
carbon
nucleophiles
to
cinnamylideneacetophenones [2], in high yields and excellent enantioselectivities using bifunctional
cinchona alkaloid derivatives as chiral organocatalysts. The presence of a second unsaturation,
extending the !-system gives another possible site for the nucleophilic attack, at the "-position,
resulting in a 1,6-addition. However, this topic is still underdeveloped due to the difficult control of
the regioselectivity between the several electrophilic sites [3]. Indeed our group reported the only
example of 1,6-CA of several carbon nucleophiles to (E)-2-styrylchromones (2-SC) [4]. Our group
also developed the first methodology that combines a multicomponent reaction and a phasetransfer catalyst: nitromethane reacts with two cinnamylideneacetophenones molecules to give
cyclohexanes with four new stereocenters in good yields and excellent diastereoselectivity [5].
Following from this work, we have also performed a domino multicomponent 1,6-1,6-1,4 conjugate
addition reactions to 2-styrylchromones under phase-transfer catalysis leading to the synthesis of
pentasubstituted cyclohexanes [6]. Recently in have started a project on the use of carbohydrates
as source of stereodifferentiation agents, which led us to study new synthetic methods to prepare
novel sugar derived aminoalkanols [7], carbohydrate 1,2-diamines [8], 1,2-diaminoinositols and
the synthetic precursor of a wide range of glycosidase inhibitors 6-amino-1,6-dideoxynojirimycin
[9]. In the present communication we present and discuss some of our recent results on the
chemistry and some biological applications of the referred heterocyclic compounds.
[1]
[2]
[3]
[4]
[5]
[6]
[7]
[8]
[9]
A. G. Csákÿ, G. Herrán, M. C. Murcia, Chem. Soc. Rev., 2010, 39, 4080.
C. G. Oliva, A. M. S. Silva, D. I. S. P. Resende, F. A. A. Paz, J. A. S. Cavaleiro, Eur. J. Org. Chem., 2010, 3449.
E. M. P. Silva, A. M. S. Silva, Synthesis, 2012, 44, 3109.
E. M. P. Silva, A. M. S. Silva, J. A. S. Cavaleiro, Synlett, 2011, 2740.
D. I. S. P. Resende, C. G. Oliva, A. M. S. Silva, F. A. A. Paz, J. A. S Cavaleiro, Synlett, 2010, 115.
E. M. P. Silva, K. Grenda, I. N. Cardoso, A. M. S. Silva, Synlett, 2013, 24, 2375.
R. G. Soengas, A. M.S. Silva, Tetrahedron, 2013, 69, 3425.
R. C. Acúrcio, R. G. Soengas, A. M. S. Silva, Filipe A. Almeida Paz, Synlett, 2013, in press.
R. G. Soengas, A. M. S. Silva, Tetrahedron Lett., 2013, 54, 2156.
SOCIETE CHIMIQUE DE FRANCE, Siège social : 250, rue Saint-Jacques, F-75005 Paris
Direction générale : 28, rue Saint-Dominique, F-75007 Paris / Tél. : +33 (0)140 46 71 62 (63 Fax) / [email protected]
www.societechimiquedefrance.fr!
Association Loi 1901 reconnue dʼutilité publique – n° SIRET 329 714 216 000 10 code APE 9499Z
!
Vendredi 28 Novembre 2014 à 11H15 : Conférence du Professeur Carlos A. M. AFONSO
(Faculté de Pharmacie, Lisbonne, [email protected]) :
« From carbohydrates to furan based building blocks »
The reduction of fossil resources for energy consumption and platform chemicals for different
purposes will shift gradually to biorenewable resources such as intensive biotransformation
processes or functional transformations of existing resources that do not compete with other
important needs such as cellulose, lignin waste products and other polysaccharides.[1]
Several building blocks derived from renewable resources such as ethanol, glycerol, lactic acid,
furfural, succinic acid, levulinic acid, are already in use or considered with potential importance in
the near future.[2] Among them, 5-hydroxymethyl-furfural (HMF) has been considered a very
promising intermediate building block due to its potential rich chemistry that allows different
transformations such as to biofuels (dimethylfuran), polymer monomers (2,5-diformylfuran and
2,5-furandicarboxyllic acid), levulinic acid, adipic acid, caprolactam and caprolactone and many
other more specific molecules,[2b, 3] including active pharmaceutical ingredients.[4]
In line with our interest in the valorization of natural resources will be described recent
achievements from this laboratory on the production of carbohydrates to 5-hydroxymethylfurfural
(HMF), transformation of HMF to several building blocks, biological activity and selection guidelines
for human exposure of furfural-related compounds.[5]
[1] G. W. Huber, S. Iborra, A. Corma, Chemical Reviews 2006, 106, 4044-4098.
[2] P. Gallezot, Chem. Soc. Rev., 2012, 41, 1538-1558; b) A. Corma, S. Iborra, A. Velty, Chemical Reviews 2007, 107,
2411-2502.
[3] a) T. Stahlberg, W. J. Fu, J. M. Woodley, A. Riisager, Chemsuschem 2011, 4, 451-458; b) A. A. Rosatella, S. P.
Simeonov, R. F. M. Frade, C. A. M. Afonso, Green Chemistry 2011, 13, 754-793; c) R. J van Putten, J. C. van der Waal, Ed
de Jong, C. B. Rasrendra, H. J. Heeres,and J.G. de Vries, Chem. Rev. 2013, 113, 1499.
[4] M. Mascal, S. Dutta, Green Chemistry 2011, 13, 3101-3102.
[5] S. P. Simeonov, J. A. S. Coelho, C. A. M. Afonso, ChemSusChem, 2013, 6, 997-1000; Sowmiah Subbiah, Svilen P.
Simeonov, José M. S. S. Esperança, Luís Paulo N. Rebelo, Carlos A. M. Afonso, Green Chem., 2013, 15, 2849–2853; R. F.
M. Frade, J. A. S. Coelho, S. P. Simeonov, C. A. M. Afonso Toxicol. Res., 2014, 3, 311-314.
SOCIETE CHIMIQUE DE FRANCE, Siège social : 250, rue Saint-Jacques, F-75005 Paris
Direction générale : 28, rue Saint-Dominique, F-75007 Paris / Tél. : +33 (0)140 46 71 62 (63 Fax) / [email protected]
www.societechimiquedefrance.fr!
Association Loi 1901 reconnue dʼutilité publique – n° SIRET 329 714 216 000 10 code APE 9499Z
!
Vendredi 28 Novembre 2014 à 15H15 : Conférence du Professeur Victor de FREITAS (Faculté
des Sciences de Porto, [email protected]) :
« The chemistry of red wine colour »
Anthocyanins are water-soluble pigments presents in many plants and foods. These red pigments
are relatively unstable and can undergo several chemical transformations yielding new compounds
with different physico-chemical properties. In red wines, these transformations result in the colour
change and could also affect their taste.
Over the last century, the structures of several groups of anthocyanin-derived pigments have been
described in wines. One of the first reactions described in wines was the polymerization reaction
between anthocyanins and flavanols mediated by acetaldehyde arising from ethanol oxidation.
With the increasing knowledge of wine chemistry, acetaldehyde was found to be more and more
important as an intermediary in chemical transformations that occur in wine during ageing. Its
participation was suggested in the formation of vinylflavanol adducts (described to result from the
decomposition of the flavanol acedaldehyde-mediated adducts) that will further react with
anthocyanins by a cicloaddiction reaction yielding the red-orange pyranoanthocyanin-flavanol
pigments.
During the last years, wine yeast metabolites have been shown to contribute importantly to the
formation of some anthocyanin-derived pigments. Effectively, among the vast number of
compounds released by yeast during wine fermentation, pyruvate (as pyruvic acid), ketones,
glyoxilic acid, acetaldehyde and other higher aldehydes (propionaldehyde, isovaleraldehyde, etc.)
and acetoacetate acid react with some flavonoids. Many of these compounds were shown to react
with anthocyanins yielding pyranoanthocyanins having orange, blue or turquoise colours at acid
pH.
During wine ageing, all these chemical transformations occur concomitantly with others, such as
the direct condensation between catechins and anthocyanins, being responsible for some of the
colour changes observed
SOCIETE CHIMIQUE DE FRANCE, Siège social : 250, rue Saint-Jacques, F-75005 Paris
Direction générale : 28, rue Saint-Dominique, F-75007 Paris / Tél. : +33 (0)140 46 71 62 (63 Fax) / [email protected]
www.societechimiquedefrance.fr!
Association Loi 1901 reconnue dʼutilité publique – n° SIRET 329 714 216 000 10 code APE 9499Z
!