Synthesis and antibacterial activities of new bis-benzimidazoles

Twenty bis-benzimidazole derivatives were synthesised by the reaction of benzimidazole with appropriate alkyl halides. The compounds synthesised were identified by H-1, C-13-NMR, FT-IR and micro analysis. All compounds studied in this work were screened for their in vitro antibacterial activity against standard strains; Enterococcus faecalis (ATCC 29212), Staphylococcus aureus (ATCC 29213), Escherichia coli (ATCC 25922) and Pseudomonas aeruginosa (ATCC 27853). Ten of the compounds were found effective to inhibit the growth of gram-positive bacteria (E. faecalis and S. aureus) at MIC (minimal inhibitory concentration) values between 50-400 mug/ml. Two of the compounds showed MIC values of 200 mug/ml against gram-negative bacteria (E. coli and P aeruginosa).