Evaluation of Analgesic and Anti-Inflammatory Activities of N-Mannich Bases of Substituted 2-Mercapto-1H-Benzimidazoles.

ABSTRACT

A series of new [1-(N,N-disubstituted)aminomethyl-2-(2,4-dinitrophenyl)sulphanyl]-6-substituted- 1H-benzimidazoles (16a-19f) were synthesized by the Mannich reaction on 2-[(2,4-dinitrophenyl)sulphanyl]-5(6)- substituted-1H-benzimidazoles with appropriate secondary amine and paraformaldehyde in presence of concentrated hydrochloric acid in ethanol. The synthesized compounds have been evaluated for analgesic and antiinflammatory activities. Considerable numbers of them were found to exhibit good activity. 2-(2,4- Dinitrophenylsulphanyl)-6-methoxy-1-pyrrolidin-4-ylmethyl-1H-benzimidazole (18e) was found to be more potent analgesic than standard pentazocine and almost equivalent in its anti-inflammatory activity in comparison with the working standard diclofenac.