New substituted phenoxyisobutyric acids and esters that can be used as medicaments and correspond to the formula: ##STR1## wherein X, A, R, R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6, R.sub.7 and Z are as defined in the description. Those compounds and their physiologically tolerable salts can be used therapeutically.