Abstract :
In this work, 2-phenyl-4(3H)-3,1-benzoxazinone (1) was synthesized from benzoylation with simultaneous cyclization of anthranilic acid and benzoyl chloride. Compound 1 was treated with hydrazine hydrate to yield 3-amino-2-phenyl-4(3H)-quinazolinone (2). Reaction of compound 2 with aromatic aldehydes/ketones resulted Schiff bases 3-6. Furthermore, treated of compound 1 with thiosemicarbazide yield compound 7, which on reaction with chloroacetic acid in the presence of sodium acetate gave 3-[(4-oxo-1,3-thiazolidin-2-yliden)amino]-2-phenylquinazolin-4(3H)-one(8). On the other hand, 2-substitutedquinazolin-4(3H)-one (9-12) were also synthesized from the reaction of anthranilic acid with different substituted amides in acetic acid. All newly synthesized compounds were characterized using different methods of spectroscopy such as IR, 1H-NMR and 13C-NMR. The antibacterial activity of all of the synthesized compounds was also reported. All synthesized compounds have been found to be active against both Grampositive and Gram-negative bacteria but compounds 4 and 8 were the most active one