Synthesis, characterization, and antileishmanial activity of neutral N-heterocyclic carbenes gold(I) complexes

Eur J Med Chem. 2018 Jan 1:143:1635-1643. doi: 10.1016/j.ejmech.2017.10.060. Epub 2017 Oct 24.

Abstract

A series of five new mononuclear neutral gold(I) complexes containing N-heterocyclic carbenes (NHCs) was synthesized and fully characterized by spectroscopic methods. The X-ray structures of four complexes are presented. These gold(I) complexes together with four other neutral gold(I)-NHC complexes previously described were evaluated in vitro against Leishmania infantum promastigotes and axenic amastigotes. Moreover, their cytotoxicity was assessed on the murine macrophages J774A.1. Except one complex (10), eight gold(I)-NHC-Cl complexes show potent activity against the pathological relevant form of L. infantum amastigote with IC50 in the low micromolar and submicromolar range and five of them exhibit a SI close to 10. The lead-complex 11 displays a very high and selective activity (IC50 = 190 nM, SI = 40.29) and constitutes the best promising gold(I)-based drug of this series.

Keywords: Antileishmanial activity; Gold; J774.1A; Leishmania infantum; N-heterocyclic carbene; Selectivity.

MeSH terms

  • Animals
  • Antiprotozoal Agents / chemical synthesis
  • Antiprotozoal Agents / chemistry
  • Antiprotozoal Agents / pharmacology*
  • Cell Line
  • Dose-Response Relationship, Drug
  • Heterocyclic Compounds / chemistry
  • Heterocyclic Compounds / pharmacology*
  • Leishmania infantum / drug effects*
  • Macrophages / drug effects
  • Methane / analogs & derivatives*
  • Methane / chemistry
  • Methane / pharmacology
  • Mice
  • Molecular Structure
  • Organogold Compounds / chemical synthesis
  • Organogold Compounds / chemistry
  • Organogold Compounds / pharmacology*
  • Parasitic Sensitivity Tests
  • Structure-Activity Relationship

Substances

  • Antiprotozoal Agents
  • Heterocyclic Compounds
  • Organogold Compounds
  • carbene
  • Methane