Copper-Catalyzed Anomeric O-Arylation of Carbohydrate Derivatives at Room Temperature.

Direct and practical anomeric O-arylation of sugar lactols with substituted arylboronic acids has been established. Using copper catalysis at room temperature under an air atmosphere, the protocol proved to be general, and a variety of aryl O-glycosides have been prepared in good to excellent yields. Furthermore, this approach was extended successfully to unprotected carbohydrates, including α-mannose, and it was demonstrated here how the interaction between carbohydrates and boronic acids can be combined with copper catalysis to achieve selective anomeric O-arylation.

Stereoretentive Copper-Catalyzed Directed Thioglycosylation of C(sp2 )-H Bonds of Benzamides.

An efficient thioglycosylation of C(sp2 )-H bonds with thiosugars has been established for the first time. Using only Cu(OAc)2 ⋅H2 O as a catalyst and Ag2 CO3 as an additive in DMSO, the protocol proved to have broad scope, and a variety of complex thioglycosides have been prepared in good yields with exclusive ß-selectivity.

Pd-Catalyzed Coupling of Bromo-N- (ß-glucopyranosyl)quinolin-2-ones with Amides: Synthesis of N-glucosyl-6BrCaQ Conjugates with Potent Anticancer Activity.

A series of N-glycosyl- 6BrCaQ conjugates was synthesized through a Pd-catalyzed cross-coupling reaction between brominated N-glycosyl quinolin-2-one derivatives and various nitrogen nucleophiles. Antiproliferative assays revealed that this new series of analogues represents a promising class of antitumor compounds as illustrated by the high biological activity observed for several derivatives towards different cancer cell lines compared to the non-glycosylated congeners.

One-Pot Assembly of Unsymmetrical Biaryl Thioglycosides through Chemoselective Palladium-Catalyzed Three-Component Tandem Reaction.

A range of unsymmetrical biaryls bearing thiosugars could be synthesized in a one-pot multicomponent approach using one catalytic palladium system that permitted the C-S and C-C bonds to be formed sequentially. The reaction showed a high selectivity and was applied to a broad variety of substrates giving access to novel glycosylated biaryl structures in good yields.