Positive allosteric modulators of the α7 nicotinic acetylcholine receptor: SAR investigation around PNU-120596

Bioorg Med Chem Lett. 2023 Sep 1:93:129433. doi: 10.1016/j.bmcl.2023.129433. Epub 2023 Aug 7.

Abstract

The α7 nicotinic acetylcholine receptor is a calcium permeable, ligand-gated ion channel that modulates synaptic transmission in the hippocampus, thalamus, and cerebral cortex. Previously disclosed work described PNU-120596 that acts as a powerful positive allosteric modulator of the α7 nicotinic acetylcholine receptor. The initial structure-activity relationships around PNU-120596 were gleaned from screening a large thiazole library. Independent systematic examination of the aryl and heteroaryl groups resulted in compounds with enhanced potency and improved physico-chemical properties culminating in the identification of 16 (PHA-758454). In the presence of acetylcholine, 16 enhanced evoked currents in rat hippocampal neurons. In a rat model of impaired sensory gating, treatment with 16 led to a reversal of the gating deficit in a dose-dependent manner. These results demonstrate that aryl heteroaryl ureas, like compound 16, may be useful tools for continued exploration of the unique biology of the α7 nicotinic acetylcholine receptor.

Keywords: Allosteric; PAM; nAChR.

MeSH terms

  • Allosteric Regulation
  • Animals
  • Hippocampus
  • Isoxazoles / chemistry
  • Isoxazoles / pharmacology
  • Phenylurea Compounds / chemistry
  • Rats
  • Receptors, Nicotinic*
  • alpha7 Nicotinic Acetylcholine Receptor*

Substances

  • alpha7 Nicotinic Acetylcholine Receptor
  • 1-(5-chloro-2,4-dimethoxyphenyl)-3-(5-methylisoxazol-3-yl)urea
  • Phenylurea Compounds
  • Isoxazoles
  • Receptors, Nicotinic