title: Cardiotonic agents. 2. (Imidazolyl)aroylimidazolones, highly potent and selective positive inotropic agents.
abstract: A series of 4-alkyl-1,3-dihydro-5-[(1H-imidazolyl)benzoyl]-2H-imidazol-2-ones 9 was synthesized and evaluated in vitro for positive inotropic and cyclic AMP phosphodiesterase inhibitory activity. A wide range of inotropic and enzyme-inhibitory potencies was observed, substitution on the imidazolyl moiety being the major determinant of activity. The 4-ethyl-5-[4-(1H-imidazol-1-yl)benzoyl] congener 9g exhibited the highest potency in vitro. Incorporation of a methyl group at the imidazolyl 2-position gave 9h, which was less potent but remarkably selective in vivo for positive inotropic effects over heart rate and hypotensive effects.
mesh_terms: D015105:3',5'-Cyclic-AMP Phosphodiesterases / Q000037:antagonists & inhibitors*; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D055598:Chemical Phenomena; D002621:Chemistry; D005289:Ferrets; D006339:Heart Rate / Q000187:drug effects; D007093:Imidazoles / Q000138:chemical synthesis / Q000494:pharmacology*; D009200:Myocardial Contraction / Q000187:drug effects*; D010210:Papillary Muscles / Q000502:physiology; D013268:Stimulation, Chemical; D013329:Structure-Activity Relationship
chemical_list: D007093:Imidazoles; D015105:3',5'-Cyclic-AMP Phosphodiesterases