SYNTHESIS OF NOVEL SERIES OF SUBSTITUTED 1,3,4-THIADIAZOLE/IMIDAZO (2,1-b)-1,3,4-THIADIAZOLES; A NOVEL CLASS OF POTENT ANTIINFLAMMATORY AND ANALGESIC AGENTS

摘要

A novel series of substituted 1,3,4-thiadiazoles (3a-b) and imidazo (2,1-b)-1,3,4-thiadiazoles (4a-j) were synthesized by the reaction between Schiff bases of 1,3,4-thiadiazoles (2a-b) with thioglycollic acid in the presence of ethanol and 2-amino-5-(substituted phenyl)-1,3,4-thiadiazoles (1a-c) with different substituted aryl/heteroaryl α-bromoketones in dry ethanol respectively. The purity of these compounds was confirmed by melting point and TLC. Structures of these compounds were confirmed on the basis of IR, ~1H NMR and Mass spectral data. The title compounds were screened for antiinflammatory and analgesic activities using carrageenan induced rat paw edema method and acetic acid induced writhing method respectively. The results showed that compounds 4b, 4c, 4d, 4i and 4j exhibited good anti-inflammatory activity as compared with standard drug Diclofenac and compounds 4b, 4c and 4i showed good analgesic activity as compared with standard drug Aspirin.