carbohydrates


Mlynarski, J.; Gut, B.
Organocatalytic Synthesis of Carbohydrates (Tutorial Review)
Chem. Soc. Rev. 2012 41 587-596 (link to page)


The key role of carbohydrates in biological processes and their visible existence in our everyday life have stimulated the interest of leading research groups on the smart and simple synthesis of common and rare sugar molecules. Now, more than 120 years after Fischer's first synthesis of(D)-glucose (1890), we are witnessing important development in this field of total synthesis. Using modern methods of direct activation of carbonyl compounds chemists can prepare sugars in an elegant and efficient way similar to that of Nature. This tutorial review presents recent impressive progress in the area of de novo synthesis of carbohydrates by using organocatalytic direct aldol reaction as a key step.


Buda, S.; Nawój, M.; Gołębiowska, P.; Dyduch, K.; Michalak, A.; Mlynarski, J.
Application of 2-Substituted Benzyl Groups in Stereoselective Glycosylation
J. Org. Chem. 2015 80 770-780 (link to page)


The use of 2-O-(2-nitrobenzyl) and 2-O-(2-cyanobenzyl) groups control stereoselective formation of 1,2-trans-glycosidic linkage via arming participation effect. Observed stereoselectivity arise likely from the intramolecular formation of cyclic intermediate between electron rich substituent and donor oxacarbenium ion providing expected facial selectivity for the attack of the glycoside acceptor. The stereodirecting effect of the 2-nitro- and 2-cyanobenzyl groups attached at remote position (C-3, C-4, and C-6) of donor molecule have also been investigated. To prove postulated mechanism based on participation effect of 2-substituted benzyl groups in the glycosylation stereoselectivity we used DFT theoretical calculation methodology.