Utilization of benzoxazinone for synthesis quinazolinone derivatives with 3-heterocycle side chain. treatment of benzoxazinon 1 with cyano acetohydrazide or thionocarbohydrazide gave the quinazolinone derivatives 2 or 12. quinazolinone 2 has been utilized as synthon for new pyridinone, oxazet, thiazole, thiazolidinone and quinazolinone derivatives. Thiosemicarbazide and thiosemicarbazone deriv...