Synthesis and Screening of Aryl-4,5-Diphenylimidazole-2-Sulphones as Antimicrobial Agents

G. Nagalakshmi1* and L. Baskar2

¹Department of Pharmaceutical Chemistry, The Erode College of Pharmacy, Erode - 638 112, Tamilnadu (India) ²Department of Pharmaceutical Sciences, Birla Institute of Technology, Mesra, Ranchi - 835 215 (India)

In the present study, 2-mercapto-4,5-diphenylimidazole 3 has been synthesized by the fusion of benzoin 1 with thiourea 2 in an oil bath. The compound 3 on reaction with various aryl halides 4a-4j in presence of alcoholic potassium hydroxide yields 2-arylthio-4,5-diphenylimidazole 5a-5j. Compound 5a-5j has been oxidized with hydrogen peroxide in presence of glacial acetic acid affords title compounds 6a-6j. The structural assignment of this compounds 6a-6j has been made on the basis of elemental analysis, UV, IR and 1H NMR spectral data. The synthesized compounds were screened for their invitro growth inhibiting activity against different strains of bacteria and fungi viz., Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, Candida albicans and Aspergillus niger were compared with the standard antibiotics such as ciprofloxacin (5μg/ml), norfloxacin (10μg/ml) and fluconazole (100μg/ml) using well agar diffusion technique. Compounds 5a, 5c, 5e and 5h showed comparable antibacterial activity.

Aryl-4;5-diphenylimidazole-2-sulphones; 2-Mercapto-4;5-diphenylimidazole; 2-arylthio-4,5-diphenylimidazole; norfloxacin; antimicrobial evaluation