Design and Synthesis of Non-Peptide, Selective Orexin Receptor 2 Agonists

Orexins are a family of neuropeptides that regulate sleep/wakefulness, acting on two G-protein-coupled receptors, orexin receptors 1 (OX1R) and 2 (OX2R). Genetic and pharmacologic evidence suggests that orexin receptor agonists, especially OX2R agonist, will be useful for mechanistic therapy of the sleep disorder narcolepsy/cataplexy. We herein report the discovery of a potent (EC50 on OX2R is 0.023 μM) and OX2R-selective (OX1R/OX2R EC50 ratio is 70) agonist, 4′-methoxy-N,N-dimethyl-3′-[N-(3-{[2-(3-methylbenzamido)­ethyl]­amino}­phenyl)­sulfamoyl]-(1,1′-biphenyl)-3-carboxamide 26.