Cardioselective beta-adrenoceptor blocking actions of some 2-methoxyphenylethanolamines in guinea pig tissues.
A series of new phenylethanolamines with 2-methoxy and/or 4-methyl, 4-chloro, or 4-bromo ring substituents and either N-isopropyl or N-tert butyl substituents have been synthesized and tested for beta 1- and beta 2-adrenoceptor blocking activity using isolated guinea pig atrial and tracheal preparations. Each of the disubstituted N-isopropyl derivatives was a potent antagonist, and the 2-methoxy-4-methyl derivative had a 40-fold beta 1/beta 2-receptor selectivity. Atenolol was shown to have a 32-fold selectivity in the same tests.
D000319:Adrenergic beta-Antagonists; D000818:Animals; D001262:Atenolol / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D006168:Guinea Pigs; D006325:Heart Atria / Q000187:drug effects; D007545:Isoproterenol / Q000494:pharmacology; D010627:Phenethylamines / Q000494:pharmacology*; D011433:Propranolol / Q000494:pharmacology; D014132:Trachea / Q000187:drug effects
D000319:Adrenergic beta-Antagonists; D010627:Phenethylamines; D001262:Atenolol; D011433:Propranolol; D007545:Isoproterenol