Subnanomolar Affinity and Selective Antagonism at α7 Nicotinic Receptor by Combined Modifications of 2-Triethylammonium Ethyl Ether of 4-Stilbenol (MG624)

J Med Chem. 2023 Jan 12;66(1):306-332. doi: 10.1021/acs.jmedchem.2c01256. Epub 2022 Dec 16.

Abstract

Modifications of the cationic head and the ethylene linker of 2-(triethylammonium)ethyl ether of 4-stilbenol (MG624) have been proved to produce selective α9*-nAChR antagonism devoid of any effect on the α7-subtype. Here, single structural changes at the styryl portion of MG624 lead to prevailing α7-nAChR antagonism without abolishing α9*-nAChR antagonism. Nevertheless, rigidification of the styryl into an aromatic bicycle, better if including a H-bond donor NH, such as 5-indolyl (31), resulted in higher and more selective α7-nAChR affinity. Hybridization of this modification with the constraint of the 2-triethylammoniumethyloxy portion into (R)-N,N-dimethyl-3-pyrrolidiniumoxy substructure, previously reported as the best modification for the α7-nAChR affinity of MG624 (2), was a winning strategy. The resulting hybrid 33 had a subnanomolar α7-nAChR affinity and was a potent and selective α7-nAChR antagonist, producing at the α7-, but not at the α9*-nAChR, a profound loss of subsequent ACh function.

Publication types

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

MeSH terms

  • Ether
  • Ethers
  • Ethyl Ethers
  • Receptors, Nicotinic*
  • alpha7 Nicotinic Acetylcholine Receptor

Substances

  • triethyl-(beta-4-stilbenoxyethyl)ammonium
  • Receptors, Nicotinic
  • 4-hydroxystilbene
  • Ether
  • alpha7 Nicotinic Acetylcholine Receptor
  • Ethyl Ethers
  • Ethers