New pseudodimeric aurones as palm pocket inhibitors of Hepatitis C virus RNA-dependent RNA polymerase

Eur J Med Chem. 2016 Jun 10:115:217-29. doi: 10.1016/j.ejmech.2016.03.005. Epub 2016 Mar 10.

Abstract

The NS5B RNA-dependent RNA polymerase (RdRp) is a key enzyme for Hepatitis C Virus (HCV) replication. In addition to the catalytic site, this enzyme is characterized by the presence of at least four allosteric pockets making it an interesting target for development of inhibitors as potential anti-HCV drugs. Based on a previous study showing the potential of the naturally occurring aurones as inhibitors of NS5B, we pursued our efforts to focus on pseudodimeric aurones that have never been investigated so far. Hence, 14 original compounds characterized by the presence of a spacer between the benzofuranone moieties were synthesized and investigated as HCV RdRp inhibitors by means of an in vitro assay. The most active inhibitor, pseudodimeric aurone 4, induced high inhibition activity (IC50 = 1.3 μM). Mutagenic and molecular modeling studies reveal that the binding site for the most active derivatives probably is the palm pocket I instead of the thumb pocket I as for the monomeric derivatives.

Keywords: Aurones; Hepatitis C virus; RNA-dependent RNA polymerase.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antiviral Agents / chemical synthesis
  • Antiviral Agents / chemistry
  • Antiviral Agents / pharmacology*
  • Benzofurans / chemical synthesis
  • Benzofurans / chemistry
  • Benzofurans / pharmacology*
  • Dose-Response Relationship, Drug
  • Enzyme Inhibitors / chemical synthesis
  • Enzyme Inhibitors / chemistry
  • Enzyme Inhibitors / pharmacology*
  • Hepacivirus / enzymology*
  • Microbial Sensitivity Tests
  • Molecular Structure
  • RNA-Dependent RNA Polymerase / antagonists & inhibitors*
  • RNA-Dependent RNA Polymerase / metabolism
  • Structure-Activity Relationship
  • Viral Nonstructural Proteins / antagonists & inhibitors*
  • Viral Nonstructural Proteins / metabolism

Substances

  • Antiviral Agents
  • Benzofurans
  • Enzyme Inhibitors
  • Viral Nonstructural Proteins
  • aurone
  • RNA-Dependent RNA Polymerase