A class of N-arylheteroarylalkyl imidazol-2-one compounds is described for use in treatment of circulatory disorders such as hypertension and congestive heart failure. Compounds of particular interest are angiotensin II antagonists of the formula ##STR1## wherein A is selected from ##STR2## wherein m is one; wherein R.sup.1 is selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, 4-methylbutyl, n-pentyl, neopentyl, phenyl, benzyl, phenethyl, cyclohexyl, cyclohexylmethyl, cyclohexylethyl, cyclohexanoyl, 1-oxo-2-cyclohexylethyl, benzoyl, 1-oxo-2-phenethyl, 1-oxopropyl, 1-oxobutyl, 1-oxopentyl and 2-hydroxybutyl; wherein R.sup.0 is selected from hydrido, methyl, fluoro, chloro, monofluoromethyl, difluoromethyl, trifluoromethyl, formyl, carboxyl and dimethoxymethyl; wherein R.sup.2 is selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, neopentyl, phenyl, benzyl, phenethyl, cyclohexyl, cyclohexylmethyl, propylthio, butylthio, and hydroxyalkyl; wherein each of R.sup.3, R.sup.4, R.sup.6, R.sup.7, R.sup.8, R.sup.9, R.sup.10 and R.sup.11 is hydrido and R.sup.5 must be selected from COOH, SH, PO.sub.3 H.sub.2, SO.sub.3 H, CONHNH.sub.2, CONHNHSO.sub.2 CF.sub.3, OH, ##STR3## wherein each of R.sup.42 and R.sup.43 is independently selected from chloro, cyano, nitro, trifluoromethyl, methoxycarbonyl and trifluoromethylsulfonyl; or a tautomer thereof or a pharmaceutically-acceptable salt thereof.