Synthesis of S-Glycosyl Primary Sulfonamides

The synthesis of S-glycosyl sulfonamides wherein the primary sulfonamide functional group (-SO2NH2) is directly attached to the anomeric position of a carbohydrate moiety is reported. Our general approach consists of first introducing a thioacetate group at die anomeric center of a per-O-acetylated sugar derivative. From this follows formation of a glycosyl sulfenamide (sugar-SNR2), oxidation of the sulfenamide to give a glycosyl N-protected sulfonamide (sugar-SO2NR2), and removal of the sulfonamide protecting (R) group to yield a primary sulfonamide at the anomeric center (sugar-SO2NH2). A variety of mono- and disaccharide derivatives were synthesized using this new methodology.