THIO-SUGARS .1. RADICAL-PROMOTED THIONE-THIOL REARRANGEMENT OF CYCLICTHIONOCARBONATES - SYNTHESIS OF 5-THIOGLUCOSE

The 5,6-O-thiocarbonyl-alpha-D-glucofuranose derivatives 2, when subje cted to one of the following reactions, undergo a radical-promoted thi one-thiol rearrangement to yield the 5-S-thiolcarbonates of gluco-conf iguration 8 as the major product, The reactions are, (A) thermolysis w ith a catalytic amount of tributyltin hydride and AIBN, (B) photolysis with hexabutyldistannane, and (C) thermolysis with dimethyl phosphona te and benzoyl peroxide. On the other hand, thermolysis of 2 with tria lkylsilane (condition D) yielded olefins 13 as the major product, The 5-S-gluco product 8 was converted, in three steps, to 5-thioglucose (2 1) in 55% yield.