2-(1-Naphthyloxy)ethylamines with Enhanced Affinity for Human 5-HT1Dβ (h5-HT1B) Serotonin Receptors
摘要:
Although the beta-adrenergic antagonist propranolol (1) binds at rodent 5-HT1B serotonin receptors, it displays low affinity (K-i > 10 000 nM) for its species homologue 5-HT1D beta (i.e., h5-HT1B) receptors. The structure of propranolol was systematically modified in an attempt to enhance its affinity for the latter population of receptors. Removal of the alkyl hydroxyl group, shortening of the O-alkyl chain from three to two methylene groups, and variation of the terminal amine substituent resulted in compounds, such as N-monomethyl-2-(1-naphthyloxy)ethylamine (11; K-i = 26 nM), that display significantly higher h5-HT1B affinity than propranolol. Compound 11 was shown to bind equally well at human 5-HT1D alpha (h5-HT1D) receptors (K-i = 34 nM) and was further demonstrated to possess h5-HT1B agonist character in an adenylate cyclase assay. It would appear that such (aryloxy)alkylamines may represent a novel class of 5-HT1D receptor agonists.