SYNTHESIS AND ANTIMICROBIAL EVALUATION OF 2-(4-FLUORO BENZYLTHIO)-N-(SUBSTITUTED PHENYL)PYRIMIDINE-4-AMINES

Reaction of 4-fluorobenzylchloride with 2-thiouracil (1) gave 2-(4-fluorobenzylthio)pyrimidin-4(3H)-one (2), which on chlorination with POCl₃ furnished 4-chloro-2-(4-fluorobenzylthio)-4-chloropyrimidine (3). This intermediate when treated with various substituted anilines gave desired targeted compounds 4(a-k) in 50-90% yield. Structural assignments of the synthesized compounds were based on their IR, ¹H NMR, Mass and analytical data. The antimicrobial evaluation of newly synthesized compounds was carried out by cup-plate method. The investigation of antimicrobial screening reveals that the compounds 4b, 4g, 4c and 4f showed good activity against bacterial strain B. subtilis. Compounds4a, 4e, 4b, 4c, 4f, 4g and 4h wereactive against bacterial strain P. aeruginosa. Compounds 4a and 4c were active against fungul strain A. niger. Compounds 4e, 4b and 4j showed good activity against fungal strain A. flavus. All the synthesized compounds showed excellent antifungal activity against T.viridae. Remaining compounds exhibited moderate to poor activity against bacterial and fungal strains when compared to standard drugs Gentamycin and Fluconazole respectively. So, further we have carried out the antifungal screening of all the synthesized compounds at different concentrations against T. viridae to determine their IC₅₀ values. Compounds 4e, 4b, 4g, 4i, 4d, 4f and 4j have shown better IC₅₀ values.