Synthesis and antimicrobial evaluation of spiro compound containing 1,2,4-triazole and isatin

The synthesis of 6'-Phenyl-4'-thioxo-3'-(4H-1,2,4-triazole-4-yl)-3',4'-dihydrospiro [Indoline-3,2'-[1,3,5]oxadiazine]-2-one (5a-h) is carried out by two a step reaction, beginning with acid catalyzed condensation of 4H-1,2,4-triazole-4-amine (1) with Indoline -2,3-dione (2), also called isatin, to obtain 3-(4H-1,2,4-triazole-4-ylimino)indoline-2-one (3) that on reaction with 4-(substituted)-cyclohexa-1,5-diene carbonyl isothiocyanate (4a-h) in the presence of anhydrous Zn[Cl.sub.2] gives targeted compounds. The compounds thus obtained, are characterized by IR, [sup.1]H NMR, [sup.13]C NMR, and elemental analysis data. The Compounds have been screened for their antimicrobial activity. Keywords: isatin; 4H-1,2,4-triazole-4-amine; 4-R-benzoyl isothiocyanate; antimicrobial screening