Synthesis and biological evaluation of a novel sigma-1 receptor antagonist based on 3,4-dihydro-2(1H)-quinolinone scaffold as a potential analgesic

Eur J Med Chem. 2014 May 22:79:216-30. doi: 10.1016/j.ejmech.2014.04.019. Epub 2014 Apr 8.

Abstract

The synthesis and sigma-1 receptor (σ1R) antagonist activity of a new series of 3,4-dihydro-2(1H)-quinolinone derivatives are reported. The new compounds were evaluated in vitro in sigma-1 and sigma-2 receptor-binding assays in guinea pig brain membranes. The structure-activity relationship led us to the promising derivative 7-(3-(piperidin-1-yl)propoxy)-1-(4-fluorobenzyl)-3,4-dihydro-2(1H)-quinolinone (35). The compounds with highest affinity and greatest selectivity were further profiled, and compound 35 had a high binding constant for sigma-1 receptor (Kiσ1 = 1.22 nM) and high sigma-1/2 selectivity (1066-fold). Thus, compound 35, which proved to be an antagonist of sigma-1 receptor, emerged as the most interesting candidate. In addition, compound 35 exerted dose-dependent anti-nociceptive effects in the formalin test. These characteristics suggested that the potent and selective compound 35 could be a potent candidate for pain treatment.

Keywords: 3,4-Dihydro-2(1H)-quinolinone; Analgesic; Antagonist; Sigma-1 receptor.

MeSH terms

  • Analgesics / chemical synthesis
  • Analgesics / chemistry
  • Analgesics / pharmacology*
  • Animals
  • Brain / drug effects
  • Dose-Response Relationship, Drug
  • Formaldehyde / administration & dosage
  • Guinea Pigs
  • Hydroquinones / chemical synthesis
  • Hydroquinones / chemistry
  • Hydroquinones / pharmacology*
  • Mice
  • Mice, Inbred Strains
  • Molecular Structure
  • Nociceptive Pain / chemically induced
  • Nociceptive Pain / prevention & control*
  • Pain Measurement
  • Receptors, sigma / antagonists & inhibitors*
  • Sigma-1 Receptor
  • Structure-Activity Relationship

Substances

  • Analgesics
  • Hydroquinones
  • Receptors, sigma
  • Formaldehyde
  • 3,4-dihydro-2(1H)-quinolinone