Disclosed are compounds of formula (I): ##STR00001## or stereoisomers or pharmaceutically acceptable salts thereof, wherein the groups Ar.sup.1, Ar.sup.2, A, R.sup.1, R.sup.2, R.sup.3, E.sup.1, E.sup.2, X and n are as defined in the description and claims, which are effective modulators of chemokine activity.