Derivatives of alpha- and beta-S-thiophosphates of 2-bromo-2-deoxy-D-hexopyranose

The first examples of S-thiophosphate derivatives of 2-bromo-2-deoxy sugars 7-12 were synthesized by reacting alkyl ammonium salts 1-4 of thiophosphor ic acids with alpha-1,2-cis (5) or alpha-1,2-trans dibromo sugars (6) and a ddition of free thiophosphoric acids la or 2a to 2-bromo-D-glucal (13). It was observed that the solvent determines formation of either the O- or S-gl ycosyl compound beta-Thiophosphates can be transformed to the alpha-configu ration in the presence of acid in quantitative yield. The structures of the synthesized derivatives of 7-12 were confirmed by spectroscopic methods. ( C) 1999 John Wiley & Sons, Inc.