Synthesis of fully and partially benzylated glycosyl azides via thioalkyl glycosides as precursors for the preparation of N-glycopeptides

Abstract

Fully O-benzylated mono-, di- and trisaccharide glycosyl azides representing the reducing terminal of the core structure of N-glycans were synthesized. Totally and partially benzylated thioalkyl glucosamine glycosides were converted into the corresponding glycosyl azides with trimethylsilyl azide in the presence of methyl triflate. The beta-mannosidic linkage was created by C-2 epimerization of the initially introduced beta-D-gluco-unit via oxidation followed by stereoselective reduction with tetrabutylammonium borohydride.