Mild and practical synthesis of 5-thio-D-glucopyranose and its pentaacetate derivatives

Two synthetic approaches for 5-thio-D-glucopyranose (5-TDGP) and its pentaacetates were described, focusing on different protective groups such as tert-butyldimethylsilyl and benzoyl employed to protect 3-OH. These protective groups were easily introduced from the beginning and can be removed during transformation from the corresponding mesylate of alpha-D-glucofuranose to 5,6-episulfide under mild conditions. In addition, a few purification manipulations were required for each approach. More importantly, 5-TDGP can be prepared using the two approaches starting from 200 g of starting material in 66.08 % and 64.4 % overall yields, respectively.