Synthesis of 4-thiouridine derivatives

The thionation of a protected uridine with the aid of P₂S₅ has given the corresponding 4-thiouridine derivatives, which have been phosphorylated at the 5 or the 2(3)hydroxyl. On being heated in aqueous pyridine solution with liquid hydrogen sulfide, cytidine phosphates also form 4-thiouridine phosphates. 4-Thiouridine 2,3-cyclophosphate has been obtained.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 996–1000, July, 1973.The authors thank M. Ya. Karpeiskii for his constant interest in the work and for valuable critical observations.