Glycosylation Employing Unprotected Carbohydrate Acceptor Components

This review discusses concepts towards facile non-enzymatic glycosylation of unprotected or lightly protected glycostructures. These comprise approaches in which reactivity distinction of hydroxyl groups is achieved via stannylene or boronic and borinic acid intermediates as well as via oxyanion formation along with syntheses based on selectivity implemented by the substrates themselves. Further, syntheses of complex glycostructures and oligosaccharides are shown, as well as the concept of random glycosylation towards glycoside libraries with desired equal product distribution.