A series of new quinazoline-4(3H)-one derivatives (2-15) have been synthesized using methyl α-[(4-oxoquinazolin-2yl)thio]acetate (1) as precursor.The acid hydrazide (2) was synthesized via the reaction of the ester (1) with hydrazine hydrate, whereas the thiosemicarbazide (4) was synthesized either from the reaction of the acid hydrazide (2) with ammonium thiocyanate or from the reaction of the es...