The present invention relates to novel substituted diamine derivatives for the formula wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4, X.sup.1, X.sup.2, X.sup.3, X.sup.4, A, Y and n are as described in the specification, pharmaceutical compositions containing them and intermediates used in their manufacture. More particularly, the compounds of the invention are motilin receptor antagonists useful for the treatment of associated conditions and disorders such as gastrointestinal reflux disorders, eating disorders leading to obesity and irritable bowel syndrome.