Synthesis and antibacterial evaluation of 2-substituted-4,5-diphenyl-N-alkyl imidazole derivatives

Objective: To synthesis 2-substituted-4,5-diphenyl-N-alkyl imidazole derivatives, and evaluate their antibacterial activity. Methods: A mixture of benzil (10 mmol) and ammonium acetate (0.1 mol) (immediately fused) in glacial acetic acid (25 mL) was stirred at 80-100 degrees C for 1 h under nitrogen atmosphere (to prevent incorporation of any atmospheric impurities and moisture). Substituted aldehydes (10 mmol) in glacial acetic acid (5 mL) was added drop-wise over a period of 15-20 min at the same temperature and stirred for another 4 h, the progress of the reaction was monitored by TLC test using ethyl acetate as eluent. The newly synthesized compounds were characterized by Ill, (HNMR)-H-1, (CNMR)-C-13 and by mass spectroscopy. Results: All the synthesized compounds were confirmed by spectroscopical techniques and evaluated for antimicrobial activity against Staphylococcus aureus( S. aurius), Bacilus subtilus (B. subtilus), and Escheria coli (E. call). These compounds showed antibacterial activity (zone of inhibition) against S. aurius ranged from 3 mm to 9 mmin diameter, B. subtilus, 4 -8 mm, and E. coli. 5 -12 mm. Out of 2a-2e, only 2a and 2b showed some sort of activity but none of them had considerable activity compared with that of the standard. Conclusions: All the synthesized compounds show moderate activity against the tested bacteria S. aurius, B. subtilus, and E. coli. So, further structural modification is necessary to improve the antibacterial action of 2-substituted-4,5-diphenyl-N-alkyl imidazole derivatives.