SYNTHESIS OF OLIGOSACCHARIDES, GLYCOPEPTIDES, AND GLYCOLIPIDS

Some novel concepts and recent developments in oligosaccharide and glycoconjugate synthesis are presented and discussed. The selective activation of one of a mixture of two or more glycosyl donors provides access to oligosaccharides while minimizing the number of manipulations required at the anomeric centers. A new method for sialylation using glycosyl phosphites is also presented. Developments in enzymatic glycosylation include in situ cofactor regeneration and the synthesis of unnatural glycosides. Recent applications of the above methods are the synthesis of sialyl Lewis X, ciclamycin 0, and calicheamicin and the development of a strategy for polymer-supported oligosaccharide synthesis. Some recently reported methods for synthesizing glycosylamino acids as structural subunits of glycopeptides are also discussed.