Design, Synthesis, In vitro Antimicrobial and Antioxidant Evaluation of Novel Pyrimidine Derivatives

In this study, a new series of 2-amino-6-(substituted)pyrimidin-4-yl-2Hchromen- 2-one analogues (S1-S15) was prepared by using the Knovengeal condensation method and evaluated for antimicrobial as well as antioxidant activity. To ensure the progress and confirmation of the reactions, TLC was employed. The melting points (MP) were ascertained utilising a Sunbim-made sonar melting point device produced in India. To confirm the chemical structures of these compounds, we employed a range of techniques, including FT-IR, MS, 1H-NMR, and Elemental analysis. The antimicrobial and antifungal activity was evaluated using the tube dilution method, and a DPPH assay was used to assess antioxidant activity. Within the series, S1 demonstrated strong antibacterial efficacy against S. Aureus, with a minimum inhibitory concentration value of 16.26μg/ml, while compound S7 displayed significant potential against B. subtilis and E. coli, with a MIC value of 17.34μg/ml. For antifungal activity, compounds S7 and S11 are the most potent against A. niger, showing a minimum inhibitory concentration of 17.34μg/ml. In the evaluation of antioxidant activity, it was observed that compounds S2 and S4 displayed outstanding antioxidant properties, with IC50 values of 13.33μg/ml and 43.13μg/ml. The newly created derivatives exhibited robust antimicrobial and antioxidant characteristics upon assessment through designated methodologies, surpassing the efficacy of conventional drugs in the comparative analysis. Notably, compounds S1, S2, S7, S4, and S11 exhibited even greater activity than the reference drugs. Their structure-activity relationship was also discussed.