A new series of the title compounds incorporated into diverse N and O heterocyclic moieties of pharmacoavailability as anti-inflammatory or analgesic agents, were synthesized starting with 6-bromo-2-phenyl-4H-3,1-benzoxazin-4-one (I) by its fusion with p-aminoacetophenone to give the intermediate compound, 6-bromo-2-phenyl-3-(4-acetylphenyl)-4(3H)quinazolinone (II). The one pot reaction of II with the appropriate aromatic aldehydes and anhyd. ammonium acetate in the presence of either ethyl cyanoacetate or malononitrile afforded the corresponding 2(1H)-pyridone derivatives III or 2(1H)- iminopyridine derivatives IV, respectively, while its reaction with malononitrile and aromatic aldehydes in piperdine gave the 2-aminopyrans V. Also reaction of the acetyl derivative II with different aromatic aldehydes afforded the corresponding 1,3-propen-1-one derivatives VI which underwent cyclization with hydrazines to give the corresponding pyrazoline derivatives VII and with urea or thiourea to give the pyrimidones or pyrimidinethiones VIII. Some representative examples of the new compounds showed promising anti-inflammatory and analgesic activities in experimental animals.