Synthesis and Biological Evaluation of Some Heterocyclic Compounds from 4- Chlorobenzohydrazonamide

Abstract

This work consists of the preparation of different heterocyclic compoundsincluding  five, six and seven member ring starting from 4-  Chlorobenzohydrazonamide (3)that prepared from 4-chloro benzonitrile(2).Cyclization of hydrazone  amide (3) with phthalic anhydride afforded 4-(3-(4-chlorophenyl)-1H-1,2,4-triazol-5-yl)benzoic acid(4) . Heating of hydrazone amide (3) with ammonium thiocyanate in putanol gave 3-(4-chlorophenyl)-1H-1,2,4-triazol-5-amine (5).On the other hand, direct cyclization of 4-Chlorobenzohydrazonamide (3)with alpha-diketonegave a new derivative of 3-(4-chlorophenyl)-6-ethyl-5-methyl-1,2,4-triazine(6).When starting material (3)allowed to reacted with different  1,3-bifunctional reagents such as ethylcyanoacetate, ethyl acetoacetate,(4-chlorobenzylidene) malononitrileand 4-(dimethylamino)but-3-en-2-onefor further heterocyclization affording the condensation compounds 7-amino-3-(4-chlorophenyl)-1H-1,2,4-triazepin-5-ol,  3-(4-chlorophenyl)-7-methyl-6H-1,2,4-triazepin-5-ol,7-amino-3,5-bis(4-chlorophenyl)-4H-1,2,4-triazepine-6-carbonitrile and3-(4-chlorophenyl)-7-methyl-4H-1,2,4-triazepinerespectively.