A facile protocol for direct conversion of unprotected sugars into phenyl 4,6-O-benzylidene-per-O-acetylated-1,2-trans-thioglycosides

摘要

A short and practical methodology for conversion of unprotected Dg-glucose,maltose,cellobiose and lactose into the corresponding phenyl 4,6-O-benzylidine-per-O-acetylated-1,2-trans-thioglycosides is described.The protocolis based on the execution of vie reactionsteps (bromoacetylation,thiophenolysis under phase transfer catlaysis conditions,decaetylation,,benzylidenation and acetylation) in one continuous procedure and provides a fast access to the title compounds as pure crystalline products without chromatographic purification.