Study on Syntheses and Antimicrobial Activities of Derivatives of 3-Amino-2-methyl-quinazolin-4-(3H)-one

3-amino-2-methyl-quinazolin-4-(3H)-one (1) was synthesised in this study by reacting N-acetyl anthranilic acid with acetic anhydride and then treating the mixture with hydrazine hydrate in pyridine. Compound 1 yields 3-chloroethanoylamino-2-methyl-quinazolin-4-(3H)-one(2) when treated with chloro acetyl chloride. By reacting the substituted derivative 2 with aliphatic and aromatic secondary amines, the final compounds 4a-g were obtained. The elemental analysis, IR, and 1H NMR data were used to determine the structural assignment of this compound 4a-g. The compounds were tested for growth inhibitory action in vitro by determining the minimal inhibitory concentration. inhibitory concentration against various bacterial and fungal strains Compounds 4a, 4b, 4e, and 4g have the highest antibacterial activity, while compounds 4a, 4b, 4d, and 4e have the strongest antifungal activity.