| abstract |
A peptide of the formula IX-A-D-Trp-Ywherein X is hydrogen, glycine, alanine, leucine, isoleucine, valine, N-valine, proline, tyrosine, phenylalanine, tryptophan, D-alanine, D-leucine, D-isoleucine, D-valine, D-N-valine, D-proline, D-tyrosine, D-phenylalanine, D-tryptophan, gamma -aminobutyric acid or xi -aminocaproic acid; A is D-gluptamic acid or D-y-glutamic acid; and Y is glycine, alanine, leucine, isoleucine, valine, N-valine, proline, tyrosine, phenylalanine, tryptophan, D-alanine, D-leucine, D-isoleucine, D-valine, D-N-valine, D-proline, D-tyrosine, D-phenylalanine, D-tryptophn, gamma -aminobutyric acid, xi -aminocaproic acid, hydroxyl, or an amide group. |