The scheme of this work involves synthesis of different five and six membered heterocyclic rings starting from isonicotinic acid hydrazide and p-hydroxy methylbenzoate .This work is divided into seven different parts and the reaction steps for part are summarized in the comprehensive scheme.
First part:
This part involved the synthesis of fused thiadiazine ring derived from the cyclization of (-NH2 and –SH) of the 3-mercapto-4-amino-5-aryl-1,2,4-triazole by treatment with p-bromophenacyl bromide. The triazole derivatives were synthesized by treating the previous acid hydrazides with carbon disulfide. Scheme.
Second part:
This part involves the synthesis of pyrazole and pyrazolone derivatives from the reaction of (-NH-NH2) group of the starting materials with acetylaceton, ethylacetoactate. Scheme.
Third part:
This part involves the synthesis of ∆4-oxazoline and triazole derivatives via the reaction of the acid hydrazides with phenyl isocyanates and cyclization of the resulted products with p-bromophenacyl bromide and with 2N NaOH. Scheme.
Fourth part:
This part involves the synthesis of oxadiazole derivatives from the reaction of (-NH-NH2) group of the starting materials with carbon disulfide. Scheme.
Five part:
This part involved the synthesis of Schiff base derivatives from the reaction of (-NH-NH2) group of the starting materials with different aldehydes. Scheme.
Six part:
This part involved the synthesis of oxazole and thiazole derivatives via the reaction of p-hydroxy methylbenzoate with urea and thiourea and cyclization of the resulted products with p-bromophenacyl bromide. Scheme.
Seven part:
This part deals with the study of antibacterial activities of some of the synthesized compounds and comparing these activities with that of the starting materials. These activities were determined in vitro using disc diffusion method against three pathogenic strains of bacteria (Escherichia Coli and staphylococcus aureus), the results revealed that some of these compounds showed measurable activity.
