Thiopyrimidine derivatives: synthesis and antibacterial activity

Eleven thiopyrimidine derivatives have been synthesized and their antibacterial activity has been studied against four Gram positive (Bacillus cereus ATCC11778, Staphylococcus aureus ATCC29737, Staphylococcus epidermidids NCIM2493, and Micrococcus luteus ATCC10240) and three Gram negative (Proteus mirabilis NCIM2241, Escherichia coli ATCC25922, and Klebsiella aerogenes NICM2098) bacteria. The antibacterial activity was evaluated using the agar well diffusion method. The thiopyrimidine derivatives showed various activity against different bacterial strains, depending on their structural formula. Gram positive bacteria were more susceptible than Gram negative bacteria; E. coli was the most resistant, and B. cereus was the most susceptible bacteria. A thiopyrimidine derivative with methoxy group at the para position showed the best antibacterial activity, while the substitution of chloro, bromo, and methyl groups decreased the activity.