Synthesis, anti-inflammatory and analgesic evaluation of thiazole/oxazole substituted benzothiazole derivatives

Abstract

Non-Steroidal biologically active heterocyclic compounds 4-(2-(4-chlorophenyl) benzo[d]thiazol-3(2H)-yl)-N-((3-substituted-2-hydrobenzo[d]thiazol-2-yl)methylene) thiazol-2-amine (3a-3d), 4-(2-(4-chlorophenyl)benzo[d]thiazol-3(2H)-yl)-N-((3-substituted - 2-hydrobenzo [d]thiazol-2-yl)methylene)oxazol-2-amine (3a'-3d'), (Z)-N'-(4-(2-(4-chlorophenyl)benzo[d]thiazol-3(2H)-yl)thiaol-2-yl)-N-(4-substituted phenylimino)-3-substituted-2-hydrobenzo[d]thiazole-2-carboxamidine (4a-4 h) and (Z)-N'-(4-(2-(4-chlorophenyl)benzo[d]thiazol-3(2H)-yl)oxazol-2-yl)-N-(4-substituted phenylimino) - 3-substituted-2-hydrobenzo[d]thiazole-2-carboxamidine (4a'-4h') were synthesized starting from 2-chloro-1-(2-(4-chlorophenyl)benzo[d]thiazol-3(2H)-yl) ethanone (1). The structure configuration of newly synthesized compounds has been determined by elemental analysis and various spectroscopic (IR, ¹HNMR and GCMS) techniques. These compounds were tested for their anti-inflammation, analgesic, ulcerogenic, acute toxicity and free radical scavenging action and compared with reference drugs in albino rats. Compound 4-(2-(4-chlorophenyl)benzo[d]thiazol-3(2H)-yl)-N-((3-substituted-2-hydrobenzo [d]thiazol-2-yl)methylene)thiazol-2-amine (3c) was the most active compound than reference drug at a dose of 50 mg/kg p.o.

Keywords: Acute toxicity; Analgesic; Anti-inflammation; Benzothiazole; Free radical scavenging; Oxazole; Thiazole; Ulcerogenic.