| 摘要 |
<p>There is disclosed biologically active peptides of the formula <IMAGE> (I) where X is a hydrogen atom, an N-terminus protecting group (any of an acyl-type protecting group, an aromatic urethane-type protecting group, an alkyl-type protecting group, or an alkyl urethane type protecting group), or a residue of a natural L-amino acid or a dipeptide formed of two natural L-amino acids, wherein the free amino group may be replaced by any of the foregoing N-terminus protecting groups; Y is a hydrogen atom or a protecting group for the phenolic hydroxyl group of tyrosine; A is a D-amino acid residue with a lower (thio) alkyl side chain; B is a neutral L-amino acid residue, a glycine residue, or an N-methyl amino acid residue; C is a direct bond or an amino acid or di-or tripeptide residue; and W is OH, OR, NH2, NHR, N(R)2, NH-NH2, where R is an alkyl, cycloalkyl or aralkyl group of 1 to 7 carbon atoms or NHNHR' where R' is a hydrogen atom, linear or branched alkyl, cycloalkyl; alkenyl, a linear or branched or cyclic aliphatic urethane-type group, an aromatic urethane-type group normally used in polypeptide chemistry, a residue of an alpha -amino; alpha -imino, or beta -amino acid, or a di-or tripeptide residue, where the -NHR' bond is an amidic linkage and the amino group is free or protected by an N-terminus protecting group. The peptides have central nervous system activity and are useful as analgesics, psychotics, and neuroendocrinologicals.</p> |
