Preparation, hydrolysis and intramolecular transesterification of 3'-deoxy-3'-thioinosine 3'-S-dimethylphosphorothiolate.

Abstract The hydrolytic reactions of the dimethyl ester of 3′-deoxy-3′-thioinosine 3′-S-phosphorothiolate have been followed over a wide aciditty range by HPLC. At pH > 3, only hydroxide ion catalyzed isomerization to the 2′-dimethylphosphate takes place, whereas under more acidic conditions hydrolysis to the 2′-monomethylphosphate and 3′-S-monomethylphosphorothiolate competes. The latter is the only product accumulating in very acidic solutions (1 M hydrochloric acid). Mechanisms of the reactions are discussed.