Synthesis of novel 5-phenylthio-2,4-disubstituted pyrimidine analogs

Abstract

5-Phenylthio-2,4-disubstituted pyrimidines were prepared in three steps starting from 5-chlorouracil. Reaction of 5-chlorouracil with thiophenol under basic condition furnished the desired 5-phenylthiouracil, which on chlorination using excess POCI 3 yielded the synthon 5-phenylthio-2,4- dichloropyrimidine. Aromatic nucleophilic substitution reaction of 5-phenylthio-2,4-dichloropyrimidine with various oxygen nucleophiles like sodium phenoxides and nitrogen nucleophiles like aliphatic primary amines, substituted aromatic primary amines and substituted heterocyclic primary amines furnished the target compounds, 5-phenylthio-2,4-disubstituted pyrimidines in 55-97% yield.