Synthesis and Biological Activity Studies of New 1, 2-diazin-dione, 1, 3, 4-oxadiazole, ∆4-oxazoline, 4-thiazolidinone and 1, 3-oxazepin-dione derivatives

          The scheme of this work involves synthesis of new five, six and seven membered heterocyclic rings derived from p-Toluic acid [1].This work is divided into four parts: -Part one: - Include synthesizing phthalazin, pyridazin-dione and oxadiazole derivatives [4], [5], [6] and [7] derived from 4-methyl benzoic hydrazide [3] which was prepared from the reaction of ethyl-4-methyl benzoate [2] with hydrazine hydrate as show in scheme 1.intermolecular cyclization of semicarbazide derivatives [8], [9]  with 4-bromophenancyl bromide respectively, as shown in Scheme 2.