N-aryl-2-aminobenzimidazoles: novel, efficacious, antimalarial lead compounds

J Med Chem. 2014 Aug 14;57(15):6642-52. doi: 10.1021/jm500715u. Epub 2014 Jul 21.

Abstract

From the phenotypic screening of the AstraZeneca corporate compound collection, N-aryl-2-aminobenzimidazoles have emerged as novel hits against the asexual blood stage of Plasmodium falciparum (Pf). Medicinal chemistry optimization of the potency against Pf and ADME properties resulted in the identification of 12 as a lead molecule. Compound 12 was efficacious in the P. berghei (Pb) model of malaria. This compound displayed an excellent pharmacokinetic profile with a long half-life (19 h) in rat blood. This profile led to an extended survival of animals for over 30 days following a dose of 50 mg/kg in the Pb malaria model. Compound 12 retains its potency against a panel of Pf isolates with known mechanisms of resistance. The fast killing observed in the in vitro parasite reduction ratio (PRR) assay coupled with the extended survival highlights the promise of this novel chemical class for the treatment of malaria.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aminopyridines / chemistry*
  • Aminopyridines / pharmacokinetics
  • Aminopyridines / pharmacology
  • Animals
  • Antimalarials / chemistry*
  • Antimalarials / pharmacokinetics
  • Antimalarials / pharmacology
  • Benzimidazoles / chemistry*
  • Benzimidazoles / pharmacokinetics
  • Benzimidazoles / pharmacology
  • Hepatocytes / metabolism
  • Humans
  • Malaria / drug therapy
  • Malaria / mortality
  • Mice, SCID
  • Microsomes, Liver / metabolism
  • Plasmodium berghei / drug effects
  • Plasmodium falciparum / drug effects
  • Rats
  • Structure-Activity Relationship

Substances

  • 6-(1-methylpiperidin-4-yl)-N-(5-(trifluoromethyl)pyridin-2-yl)-1H-benzo(d)imidazol-2-amine
  • Aminopyridines
  • Antimalarials
  • Benzimidazoles