New methods for the synthesis of N-benzoylated uridine and thymidine derivatives; a convenient method for N-debenzoylation

An improved procedure for the synthesis of N-benzoyl-2′,3′-O-isopropylidene uridine via one-step selective N-benzoylation of 2′,3′-O-isopropylidene uridine has been developed. An efficient synthetic route to N-benzoyl thymidine via initial tribenzoylation, followed by selective hydrolysis of the benzoates is also described. De-N-benzoylation of N-benzoylated thymidine and uridine derivatives can be conveniently effected under neutral conditions, by heating with benzyl alcohol.