Imidazole derivatives of the formula ##STR1## wherein Ar.sub.1 and Ar.sub.2 are each phenyl; phenyl substituted by halogen, C.sub.1-4 alkyl, C.sub.1-4 alkoxy or C.sub.2-6 dialkylamino; pyridyl; furyl; or thienyl; with the proviso that Ar.sub.1 and Ar.sub.2 are not both unsubstituted phenyl;R.sub.1 is hydrogen, C.sub.1-4 alkyl or C.sub.1-4 alkyl substituted by hydroxy, C.sub.1-4 alkoxy or C.sub.1-6 alkanoyloxy;n is 0, 1 or 2; andZ is a C.sub.2-6 -alkyl or -alkenyl residue substituted by one or two of hydroxy, C.sub.1-4 alkoxy, C.sub.2-8 alkylenedioxy, C.sub.1-6 alkanoyloxy or benzoyloxy, or by one alkoxycarbonyl group;and the salts thereof with physiologically acceptable acids, possess valuable pharmacological properties.