Synthesis, Characterization and Antimicrobial Study of 1, 2-Disubstituted Benzimidazoles

Abstract

A series of novel disubstituted benzimidazole derivatives were synthesized by condensation of o-phenylenediamine with different aromatic aldehydes in presence of ceric ammonium nitrate forming 2-substituted benzimidazoles which on further condensation with secondary amine and formaldehyde forms 1, 2-disubstituted benzimidazoles. The purity of the synthesized compounds was monitored by thin layer chromatography and characterized by FT-IR, 1HNMR, MASS spectral analysis. The compound exhibited moderate antibacterial activity against Bacillus subtilis, good activity against Escherichia coli, compared to standard ciprofloxacin. The two synthesized compounds named 3a [ (2-{[2-(3-chlorophenyl)-1H-benzimidazol-1-yl] methyl}-1H-isoindole-1, 3(2H)-dione)] and 5a [2-{[2-(2-chlorophenyl)-1H-benzimidazol-1-yl] methyl}-1H-isoindole-1, 3(2H)-dione] were tested for the antitubercular activity showed a significant activity against Mycobacterium tuberculosis (H37Rv).