Synthesis of some benzimidazole derivatives and their antibacterial and antifungal activities

A number of new benzimidazole derivatives were synthesized by the reaction of benzimidazole with appropriate alkyl halides. The compounds synthesized were intentified by H-1-NMR, Fourier Transformation Infrared (FT-IR) and mi cro analysis. All new and related compounds studied in this work were scree ned for their in vitro antimicrobial activities against the standard strain s: Enterococcus faecalis (ATCC 29212), Staphylococcus aureus (ATCC 29213), Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27853) and the yeasts Candida albicans and Candida tropicalis. Eleven of the compounds wer e found effective to inhibit the growth of Gram-positive bacteria (E. faeca lis and S. aureus) at MIC values between 12.5-400 mug/ml. None of the compo unds exhibited antimicrobial activity against Gram-negative bacteria (E. co li and P. aeruginosa) at the concentrations studied (6.25-800 mug/ml). All compounds (except compound 3) were significantly effective against C. tropi calis with MIC values of 6.25-400 mug/ml. Eight of the tested compounds sho wed an antifungal activity against C. albicans with a range of the MICs bet ween 50 and 400 mug/ml.