Peptide and pseudopeptide derivatives of the formula: ##STR1## wherein R.sup.1 and R.sup.2 stand for defined hydrocarbyl or halo-hydrocarbyl substituents, for example alk-2-enyl radicals; .dbd.N--A-- stands for a defined amino acid residue; B, D and E, which may be the same or different, stand for a valency bond or a defined amino acid residue; F stands for a defined amino acid residue; X stands for a carboxy, ester or amide group; and the linkages between the amino acid residues are peptide linkages or at least one of said linkages is a defined pseudo linkage; and pharmaceutically-acceptable salts thereof. Processes for the manufacture of the compounds. Pharmaceutical compositions comprising one of the compounds and a pharmaceutical diluent or carrier. The compounds are antagonists at the opiate receptors, and most of them are selective .delta.-receptor antagonists.
                            肽和伪肽衍
生物的
化学式:##STR1##
其中R1和R2代表已定义的烃基或卤代烃基取代基,例如烯丙基基团;.dbd.N--A--代表已定义的
氨基酸残基;B、D和E可以相同也可以不同,代表一个价键或已定义的
氨基酸残基;F代表已定义的
氨基酸残基;X代表羧基、酯基或酰胺基;
氨基酸残基之间的连接是肽键或至少一个连接是已定义的伪键;以及其药学上可接受的盐。制备该化合物的方法。包括该化合物和药学稀释剂或载体的制药组合物。该化合物是阿片受体拮抗剂,大多数是选择性δ-受体拮抗剂。