Use of an oxazolidinone derivative of a sialyl thioglycoside as a useful glycosyl donor for α-favorable glycosidation with simple alcohols

An efficient synthesis of lauryl thioglycoside of oxazolidinones derived from N-acetyl neuraminic acid was accomplished from a known thioglycoside of Neu5Ac. The O-glycosidation reactivities of the oxazolidinones were evaluated by means of trimethylsilyl trifluoromethanesulfonate (TMSOTf) and N-iodosuccinimide (NIS) as a combined-mediator system. The glycosidation reaction of the lauryl thioglycoside with simple alcohols proceeded smoothly to yield the corresponding α-glycosides in good yields after isolation. The results suggested that the glycosylation reaction using the oxazolidinone derivative of sialic acid has excellent α-stereoselectivity and enables easy isolation of the desired product from the reaction mixture.