PEPTIDE DERIVATIVES

摘要

Compounds represented by the following general formula and salts thereof: Y-L-Tyr-Q-NR1-CH(R2)-CO-X, wherein R1 represents hydrogen or C1-6 alkyl; R2 represents optionally substituted benzyl; Q represents D- or L-Arg; Y represents two hydrogen atoms in the N-terminal amino group of L-Tyr or substituent(s) of the same, for example, C1-6 alkyl optionally having amino or carboxy; and X represents N-methyl-.beta.-alanine, etc. Because of having an analgetic effect, the compounds are usable in the treatment of cancer pain, etc.