Peptide compounds having substance P antagonism, processes for preparation thereof and pharmaceutical composition comprising the same

A compound of the formula:

• ##STR432## wherein R.sup.1 is lower alkyl, aryl, arylamino, pyridyl, pyrrolyl, pyrazolopyridyl, quinolyl, or a group of the formula:
• ##STR433## wherein the symbol of a line and dotted line is a single bond or a double bond,
• X is CH or N, and
• Z is O, S or NH
• each of which may have suitable substituent(s);
• R.sup.2 is hydrogen or lower alkyl;
• R.sup.3 is hydrogen or hydroxy;
• R.sup.4 is lower alkyl which may have suitable substituent(s), and
• R.sup.5 is ar(lower)alkyl which may have suitable substituent(s) or pyridyl(lower)alkyl, or
• R.sup.4 and R.sup.5 are linked together to form benzene-condensed lower alkylene;
• A is a bivalent residue derived from an amino acid selected from the group consisting of proline, hydroxyproline, glycine, serine, asparagine, aminoisobutyric acid, azetidinecarboxylic acid, thioproline, aspartic acid, lysine, methionine, threoine, alanine ornithine, hydroxypiperidinecarboxylic acid, 4-acyloxyproline, 4-lower alkoxyproline, 4-carboxy(lower)alkoxyproline, 4-esterified carboxy(lower)alkoxyproline, 4-lower alkylthioproline, 4-aminoproline, 4-acylaminoroline, O.sup.3 -lower alkylserine, O.sup.3 -ar(lower)alkylserine, thioproline sulfoxide, thioproline sulfone, O.sup.4 -ar(lower)alkyl hydrogen aspartate, (carbamoyl and hydroxy substituted lower alkylamino)-.beta.-aspartate, carbamoyl(lower)alkylamino-.beta.-aspartate, morpholine-.beta.-aspartate, (carbamoyl and lower alkylcarbamoyl substituted lower alkylamino)-.beta.-aspartate, N.sup.6 -acyllysine, and N.sup.5 -acylornithine, and
• Y is bond, lower alkylene or lower alkenylene, or a pharmaceutically acceptable salt thereof.