Factors Affecting Stereocontrol during Glycosidation of 2,3-Oxazolidinone-Protected 1-Tolylthio-AT-acetyl-D-glucosamine

摘要

It is demonstrated that a ring-fused 2,3-oxazolidinone-protected derivative of 1-tolylthio-N-acetyl-D-glucosamine undergoes high-yield glycosidation under mild donor activation conditions. Stereoselective formation of α-linked or β-linked glycosides is dependent on reactivity of acceptor alcohols, where rate of glycosidation correlates to stereo-chemical outcome. Evidence for the role of glycosyl triflate intermediates and the N-acetyl substituent of the 2N,3O-oxazolidinone ring in stereochemical control is presented.