Desulfation of Sulfated Carbohydrates Mediated by Silylating Reagents

Abstract

Efficient methods of desulfation are often required in carbohydrate chemistry and biochemistry. In addition to conventional desulfation methods,^1,2 we recently reported a novel desulfation method employing a silylating reagent, N,O-bis(trimethylsilyl)-acetamide.^3,4 With this reagent, the 6-O-sulfoxyl groups of the sugar moiety are regioselectively removed and newly formed hydroxyl groups are further converted by silylation into trimethylsilyloxyl groups. The desulfated carbohydrates are easily recovered after desilylation with water or aqueous methanol. Although the mechanism for this reaction remains unclear, silylating reagents can be considered as potential reagents for desulfation reaction. In the present paper, we examined various silylating reagents to find effective and new desulfation reagents for carbohydrate sulfates.