one compound , 2- [ ( 2-amino-4-hydroxypyrimidin-6-yl ) methoxy ] -4- ( 2,3-dichlorophenyl ) -3- ( ethoxycarbonyl ) -5- ( methoxycarbonyl ) -6-methyl- 1,4-dihydropyridine ( 27 , uk-56,593 ) , was identified as a potent ( ic50 = 1.6 x 10 ( -9 ) m ) , tissue-selective calcium antagonist which proved to have a markedly longer duration of action ( greater than 4.5 h ) than nifedipine in the anesthetized dog on intravenous administration .
C0012315
dihydropyridine
C0028066
nifedipine