1998 Volume 46 Issue 5 Pages 777-781
5-Alkylidene-3, 5-dihydro-4H-imidazol-4-one derivatives were synthesized and evaluated for activity as angiotensin II receptor antagonists. Substitutions at C-2 and C-5, respectively, with a propyl group and a 1-methylethylidene group resulted in the optimal compound, 3, 5-dihydro-5-(1-methylethylidene)-2-propyl-3-[[2'-(1H-tetrazol-5-yl)biphenyl-4-yl]methyl]-4H-imidazol-4-one (2b), with a pA2 value of 8.85 in rabbit aorta. When administered orally to rats 2b showed a greater inhibitory effect on angiotesin II-induced pressor response than DuP 753. Compound 2b also showed a good antihypertensive effect when administered orally to conscious sodium-depleted spontaneously hypertensive rats, with a duration of action of 24 h. These data suggest that 2b may be a useful agent for the treatment of angiotensin II-dependent diseases such as hypertension.