Synthesis, characterization and antimicrobial activity of some novel benzimidazole derivatives

Abstract

A series of novel N-((1H-benzoimidazol-1-yl) methyl)-4-(1-phenyl-5-substituted-4, 5-dihydro-1-benzoimidazol-1-yl) methyl)-4-(1-phenyl-5-substituted-4, 5-dihydro-1H-pyrazol-3-yl) benzenamine were synthesized by treating various 1-(4-((1H-benzoimidazol-1-yl) methylamino) phenyl)-3-substitutedprop-2-en-1-one with phenyl hydrazine in the presence of sodium acetate through a simple ring closure reaction. The starting material, 1-(4-((1H-benzoimidazol-1-yl) methylamino) phenyl)-3-substitutedprop-2-en-1-one,-benzoimidazol-1-yl) methylamino) phenyl)-3-substitutedprop-2-en-1-one, was synthesized from o-phenylenediamine by a multistep synthesis. All the synthesized compounds were characterized by spectroscopic means and elemental analyses. The title compounds were investigated for in vitro antibacterial and antifungal properties against some human pathogenic microorganisms by employing the agar streak dilution method using Ciprofloxacin and Ketoconazole as standard drugs. All title compounds showed activity against the entire strains of microorganism. Structural activity relationship studies reveal that compounds possessing an electron-withdrawing group display better activity than the compounds containing electron-donating groups, whereas the unsubstituted derivatives display moderate activity. Based on the results obtained, N-((1H-benzoimidazol-1-yl) methyl)-4-(1-phenyl-5-(4-(trifluoromethyl) phenyl)-4,5-dihydro-1H-pyrazol-3-yl) benzenamine 5i was found to be very active compared with the rest of the compounds and standard drugs that were subjected to antimicrobial assay.

Synthesis, Antioxidant, and Antibacterial Activities of Some New 2‐(3‐fluorobenzyl)‐1H‐benzimidazole Derivatives

“…Krishnanjaneyulu et al . revealed that MIC values ranges between of some newly synthesized benzimidazole derivatives against S. aureus and B. cereus ranges between 15.62–125 μg/mL and 7.81–125 μg/mL, respectively . In our studies, we determined MIC value of our synthesized benzimidazole derivatives against B. cereus ranges between 0.078 and 2.5 mg/mL.…”

Synthesis and Antimicrobial Activity of p-tetranitrocalix[4]arene Derivative

“…Phenyl ring, substituted with electron withdrawing substituent on the C-4 (para-position) had a good antimicrobial effect (31,32). Structural activity relationship studies reveal that compounds possessing an electron-withdrawing group display better activity than the compounds containing electron-donating groups, whereas the unsubstituted derivatives display moderate activity (33). The introduction of electron withdrawing groups appears to contribute positively to the activity.…”

Isatin – a potent anti-microbial agent

“…Gradually antibiotic resistance is increasing for many infections caused by various micro-organisms which shows significant threat and may lead to complications and treatment failures. Hence several scientists are trying to find out new anti-microbial agents by placing significant efforts (Krishnanjaneyulu et al, 2014).…”