2-(chromon-3-yl)imidazole derivatives as potential antimicrobial agents: synthesis, biological evaluation and molecular docking studies

Abstract

A series of novel 2-(chromon-3-yl)-4,5-diphenyl-1H-imidazoles (4a-h) were synthesized by one pot condensation of substituted 3-formylchromones (1a-h), benzil (2) and ammonium acetate (3) in refluxing acetic acid at 110°C under N2 atmosphere. Allylation of compounds 4a-h with allyl bromide in the presence of fused K 2 CO 3 furnishedThe synthesized compounds were characterized spectroscopically and evaluated for in vitro antimicrobial activity against various pathogenic bacterial and fungal strains by disc diffusion method. Compounds bearing electron withdrawing substituents such as bromo (4f) showed significant inhibitory activity against S. cerevisiae (MIC 1.4 μg/ml) and 4g containing chloro substituent, displayed more inhibitory potential against C. albicans (MIC 1.5), as compared to the standard drugs. Compounds 6a and 4c exhibit remarkable inhibitory potential against B. subtilis with MIC 0.98 and 1.23, respectively. The time kill assay for active compound 6a was performed by viable cell count (VCC) method to elucidate the microbicidal nature of 2-(chromon-3-yl)imidazoles. A molecular docking study of most active compounds with target 'lanosterol 14α-demethylase' (CYP51) was performed to unravel the mode of antifungal action.

An Updated Review on the Synthesis and Antibacterial Activity of Molecular Hybrids and Conjugates Bearing Imidazole Moiety

“…It was thus found that compound 431a (R 1 = R 2 = R 3 = H) and compound 428c (R 1 = R 2 = H, R 3 = Cl) exhibited excellent inhibitory activity against B. subtilis with MIC values of 2.4 and 3.2 µM, respectively. Compound 431a also displayed significant inhibitory activity against E. coli with an MIC value of 2.8 µM [249].…”

“…In 2017, Ishar and coworkers synthesised and characterised novel 3-(4,5-diphenyl-1H-imidazol-2-yl)-4H-chromen-4-ones 428 by one pot condensation of substituted 4-oxo-4H-chromene-3-carbaldehydes 429, benzil (161), and AcONH 4 in refluxing AcOH under N 2 atmosphere (Scheme 89) [249]. The subsequent reaction of compounds 428, which were obtained in yields ranging from 78 to 84%, with allyl bromide (430) in DMF at room temperature for 24 h in the presence of fused K 2 CO 3 furnished 3-(1-allyl-4,5-diphenyl-1H-imidazol-2-yl)-4H-chromen-4-ones 431 in yields ranging from 50 to 62%.…”

Design, Synthesis and Antibacterial Activity Evaluation of 4,5-Diphenyl-1<i>H</i>-Imidazoles Derivatives

“…Because the heterocyclic ring includes the core of the active moiety or pharmacophores, we have been interested in working on structural modification of imidazole and benzimidazole. Besides this, these two heterocyclics containing nitrogens can be substituted in different positions to give several compounds with antibacterial activity [10] [11].…”

Synthesis and Anticandidal and Antibacterial Activities of 5-Chloro-1-Ethyl-2-Methyl-N-Phenyl-1h-Imidazole-4-Sulphonamide and 5-Chloro-N-(3-Chlorophenyl)-1-Ethyl-2-Methyl-1h-Imidazole-4-Sulphonamide

“…Imidazole is a versatile heterocyclic compound with high therapeutic properties and a broadened scope that encouraged Medicinal Chemists to synthesise numerous novel chemotherapeutic agents as anti-cancer [20][21], anti-oxidant [22][23], anti-inflammatory [24][25], anti-microbial [26][27], anti-tubercular [28], anti-diabetic [29][30], antimalarial [31], HMG-CoA reductase inhibitory activity [32], anti-protozoa [33], anti-HIV [34], anticonvulsant [35][36]. It is a ubiquitous moiety in agricultural, medicinal, and industrial chemistry.…”