Rearrangement of 1-O-(thio-p-nitrobenzoyl)thiocarbonyl galactoside: a novel access to α-thioglycoside derivatives

The synthesis of galactosides thiolate and thioester is described by direct S-glycosylation process from 1-O-(thio-p-nitrobenzoyl)thiocarbonyl galactoside. Three novel anomeric groups are presented as potent glycoside activators: O-(thio-p-nitrobenzoyl)thiocarbonyl, O-(imidazolyl)thiocarbonyl and S-thio-p-nitrobenzoyl.