Syntheses of 5-Thio-D-Mannose from Petrochemicals and a Disaccharide Analog Containing It

Per-O-acetyl-5-thio-DL-mannose was synthesized from petrochemicals in six steps and 9% overall yield. It was then derivatized into glycosyl trichloroacetimidate and subjected to glycosidation reaction with a mannosyl acceptor to give a separatable mixture of disaccharides with 5-thio-D- and L-mannosides. This is the first synthesis of an enantiomerically pure 5-thiosugar derivative from racemic chemicals. The D-glycoside was derivatized into methyl (5-thio-α-D-mannopyranosyl)-2-O-α-D-mannopyranoside 6-phosphate as a potential inhibitor of a golgi α-1,2-mannosidase