SYNTHESIS OF S-BENZYL DERIVATIVE OF 4,6-DIAMINOPYRIMIDINE-2-THIOL

Thiopyrimidines constitute an important class of heterocyclic compounds with diverse biological activities, including antiviral, antimicrobial, antitumor, and anti-inflammatory effects. In this study, we report the synthesis of 2-(benzylthio)pyrimidine-4,6-diamine, an S-benzyl derivative of 4,6-diamino-2-mercaptopyrimidine, through nucleophilic substitution of the thiol group with benzyl chloride under basic conditions in methanol. The reaction proceeded selectively at the sulfur atom, affording the desired product in 71% yield. The structure of the compound was confirmed by infrared (IR) spectroscopy, which revealed characteristic absorption bands corresponding to amino, aromatic, and thioether functionalities. Complementary analyses included thin-layer chromatography (TLC) and melting point determination. The selective reactivity of the sulfur atom over the amino groups highlights the synthetic potential of thiopyrimidines for targeted functionalization. These findings provide a simple and efficient synthetic route to S-benzyl thiopyrimidine derivatives and establish a basis for future evaluation of their antimicrobial and pharmacological properties.