Abstract
Treatment of cytidine with liquid hydrogen sulfide-pyridine afforded 4-thiouridine in an excellent yield. Similar treatment of sodium cytidine 5'-phosphate, cytidine 5'-diphosphate (CDP), cytidine 5'-triphosphate (CTP), and CDP-choline afforded the respective 4-thiouridine phosphates. In the case of CDP and CTP the hydrolytic cleavage of pyrophosphate linkage was noticed. Several cytidine derivatives such as arabinofuranosylcytosine, 3-methylcytidine, and 2-thiocytidine also underwent sulfhydrolysis affording respective 4-thio derivatives. The present method seemed to be the most versatile procedure for the synthesis of-4 thiouracil nucleosides and nucleotides.
