SYNTHESIS, ANTIMICROBIAL AND ANTI-INFLAMMATORY ACTIVITIES OF SOME 2-(2-CHLOROPHENYL)-6-(SUBSTITUTED PHENYL)-THIAZOLO[3,2-b][1,2,4]TRIAZOLE

Nilesh A. Karande* and Lalit G. Rathi

ABSTRACT

The reaction of 2-chlorobenzohydrazide 3 with potassium thiocyanate yield {(2-chlorobenzoyl) aminothiourea 4 followed by cyclization in the presence of base afforded 5-(2-chlorophenyl)-4H-1,2,4-triazole-3-thiol 5. Condensation of 5 with various 2-bromo-1-(substituted phenyl) ethanone 6 in the presence of base afforded 2-{[5-(2-chlorophenyl)-4H-1,2,4-triazole-3-yl]sulfanyl}-1-(substituted phenyl)ethanone 7 which on further cyclization in the presence of polyphosphoric acid afforded series of fused heterocycles namely 2-(2-chlorophenyl)-6-(substituted phenyl)-thiazolo[3,2-b][1,2,4]triazole (8a-l). The structure of all the synthesized compounds were characterized by FT-IR, 1H and 13C NMR, TOF MS ES+ data and elemental (C, H, N, S) analysis. Furthermore, compounds (8a-l) were screened for their antibacterial activity against gram negative (E. coli and P. aeruginosa) and gram positive (S. aureus and B. subtilis) bacteria, antifungal activity against pathogenic fungal strains (C. albicans and A. niger) and anti-inflammatory activities. Some of the compounds exhibited promising antibacterial, antifungal and anti-inflammatory activities.

Keywords: Thiazole; Triazole; Thiazolotriazole; Antibacterial activity; Antifungal activity; Anti-inflammatory activity.