The benzimidazole based drugs show good activity against T. gondii but poor activity against its proposed enoyl reductase enzyme target

Bioorg Med Chem Lett. 2014 Feb 1;24(3):911-6. doi: 10.1016/j.bmcl.2013.12.066. Epub 2013 Dec 22.

Abstract

The enoyl acyl-carrier protein reductase (ENR) enzyme of the apicomplexan parasite family has been intensely studied for antiparasitic drug design for over a decade, with the most potent inhibitors targeting the NAD(+) bound form of the enzyme. However, the higher affinity for the NADH co-factor over NAD(+) and its availability in the natural environment makes the NADH complex form of ENR an attractive target. Herein, we have examined a benzimidazole family of inhibitors which target the NADH form of Francisella ENR, but despite good efficacy against Toxoplasma gondii, the IC50 for T. gondii ENR is poor, with no inhibitory activity at 1 μM. Moreover similar benzimidazole scaffolds are potent against fungi which lack the ENR enzyme and as such we believe that there may be significant off target effects for this family of inhibitors.

Keywords: Benzimidazole; Enoyl reductase; Toxoplasma; Triclosan.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antiparasitic Agents / chemistry
  • Antiparasitic Agents / pharmacology
  • Benzimidazoles / chemistry*
  • Benzimidazoles / pharmacology*
  • Crystallography, X-Ray
  • Drug Delivery Systems*
  • Enoyl-(Acyl-Carrier-Protein) Reductase (NADH) / antagonists & inhibitors*
  • Enzyme Activation / drug effects
  • Inhibitory Concentration 50
  • Microbial Sensitivity Tests
  • Molecular Structure
  • Toxoplasma / drug effects*

Substances

  • Antiparasitic Agents
  • Benzimidazoles
  • benzimidazole
  • Enoyl-(Acyl-Carrier-Protein) Reductase (NADH)