Synthesis and Biological Evaluation of Some Novel Polysubstituted Pyrimidine Derivatives as Potential Antimicrobial and Anticancer Agents

Synthesis and evaluation of the antimicrobial and cytotoxic activity of two series of polysubstituted pyrimidines comprising the thioether functionality and other pharmacophores, reported to contribute to various chemotherapeutic activities are described. All newly synthesized compounds were subjected to in‐vitro antibacterial and antifungal screening. Out of the compounds tested, 18 derivatives displayed an obvious inhibitory effect on the growth of the tested Gram‐positive and Gram‐negative bacterial strains, with special effectiveness against the Gram‐positive strains. Compounds 1 , 2 , 6 , 7 , 9 , 10 , 11 , 21 , and 24 revealed remarkable broad antibacterial spectrum profiles. Among those, compounds 1 , 2 , 6 , 7 , 9 , and 24 exhibited an appreciable antifungal activity against C. albicans. Compound 2 proved to be the most active antimicrobial member identified here as it showed twice the activity of ampicillin against B. subtilis and the same activity of ampicillin against M. Luteus and P. aeruginosa together with a moderate antifungal activity. Further, eleven analogs were evaluated for their in‐vitro cytotoxic potential utilizing the standard MTT assay against a panel of three human cell lines: breast adenocarcinoma MCF7, hepatocellular carcinoma HePG2, and colon carcinoma HT29. The obtained data revealed that six of the tested compounds 1 , 3 , 7 , 12 , 13 , and 15 showed a variable degree of cytotoxic activity against the tested cell lines at both the LC₅₀ and LC₉₀ levels. Compound 7 proved to be the most active cytotoxic member in this study with special effectiveness against the colon carcinoma HT29 and breast cancer MCF7 human cell lines for LC₅₀ and LC₉₀. Thus, compounds 1 and 7 could be considered as possible dual antimicrobial‐anticancer agents.