Triaryl Benzimidazoles as a New Class of Antibacterial Agents against Resistant Pathogenic Microorganisms

J Med Chem. 2017 Jul 27;60(14):6045-6059. doi: 10.1021/acs.jmedchem.7b00108. Epub 2017 Jul 11.

Abstract

A new class of nontoxic triaryl benzimidazole compounds, derived from existing classes of DNA minor groove binders, were designed, synthesized, and evaluated for their antibacterial activity against multidrug resistant (MDR) Gram-positive and Gram-negative species. Molecular modeling experiments suggest that the newly synthesized class cannot be accommodated within the minor groove of DNA due to a change in the shape of the molecules. Compounds 8, 13, and 14 were found to be the most active of the series, with MICs in the range of 0.5-4 μg/mL against the MDR Staphylococci and Enterococci species. Compound 13 showed moderate activity against the MDR Gram-negative strains, with MICs in the range of 16-32 μg/mL. Active compounds showed a bactericidal mode of action, and a mechanistic study suggested the inhibition of bacterial gyrase as the mechanism of action (MOA) of this chemical class. The MOA was further supported by the molecular modeling study.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Bacterial Agents / chemical synthesis
  • Anti-Bacterial Agents / chemistry*
  • Anti-Bacterial Agents / pharmacology
  • Benzimidazoles / chemical synthesis
  • Benzimidazoles / chemistry*
  • Benzimidazoles / pharmacology
  • DNA Gyrase / metabolism
  • Drug Resistance, Multiple, Bacterial
  • Gram-Negative Bacteria / drug effects*
  • Gram-Positive Bacteria / drug effects*
  • HeLa Cells
  • Humans
  • Microbial Sensitivity Tests
  • Models, Molecular
  • Structure-Activity Relationship
  • Topoisomerase II Inhibitors / chemical synthesis
  • Topoisomerase II Inhibitors / chemistry
  • Topoisomerase II Inhibitors / pharmacology

Substances

  • 2-methyl-1-(5-(3-((2-methyl-3H-benzoimidazole-5-carbonyl)amino)phenyl)pyridin-2-yl)-1H-benzoimidazole-5-carboxylic acid (2-dimethylaminoethyl)amide
  • 2-methyl-1-(5-(3-((2-methyl-3H-benzoimidazole-5-carbonyl)amino)phenyl)pyridin-2-yl)-1H-benzoimidazole-5-carboxylic acid (3-dimethylaminopropyl)amide
  • Anti-Bacterial Agents
  • Benzimidazoles
  • N-(4-(dimethylamino)butyl)-2-methyl-1-(5-(3-(2-methyl-1H-benzo(d)imidazole-6-carboxamido)phenyl)pyridin-2-yl)-1H-benzo(d)imidazole-5-carboxamide
  • Topoisomerase II Inhibitors
  • DNA Gyrase