Synthesis and Antimicrobial Activity of 5-chloro-1-ethyl-2-methylimidazole-4-sulfonyl-8-Quinolinoxide

Document Type: Original Article


1 Department of Chemistry, Faculty of Physical Sciences, University of Benin, Benin City, PMB 1154, Nigeria

2 Department of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Benin, Benin City, PMB 1154, Nigeria



A new 5-chloro-1-ethyl-2-methylimidazole-4-sulfonyl-8-quinolinoxide was synthesized starting from diethyloxalate via a four-reaction step. The new compound obtained in a simple and efficient procedure in the solvent and solvent-free with good yield and methanol served as a precipitating agent to isolate compound 2. The purity of 5-chloro-1-ethyl-2-methylimidazole-4-sulfonyl-8-quinolinoxide was tested by thin-layer chromatography (TLC) and characterized by Fourier transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance (NMR), Carbon-13 (C13) nuclear magnetic resonance (13C-NMR), and DEPT 135 to confirm the presence and nature of CH2. The solvent-free reaction of compound 1 was better in relation to green chemistry and better yield. The presence of solvent responsible for a color change that differentiates between compound 1 and 2 as they have the same physical data, functional group, and the chemical shift studied. The newly synthesized compound was evaluated and screened in vitro against Gram-positive (methicillin-susceptible Staphylococcus aureus, methicillin-resistant Staphylococcus aureus, and Bacillus subtilis), Gram-negative (Pseudomonas aeruginosa, Escherichia coli, and Klebsiella pneumoniae) bacterial strains, and Candida albicans using the standard microbiological method. 5-Chloro-1-ethyl-2-methylimidazole-4-sulfonyl-8-quinolinoxide exhibited weak activities when compared with the standard drug ciprofloxacin and itraconazole used for many bacterial and fungal infections respectively.


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