| 摘要 |
<p>Pentapeptides of the formula: (FORMULA) wherein R1 is hydrogen, methyl, ethyl, propyl, 2-methyl-2-pentenyl, 2-methyl-1-pentenyl, cyclopropylmethyl, or cyclobutylmethyl; R2, R3, and R4 are, independently, hydrogen or methyl; and X is -OH, -NH2, -NHCnH2n+1 where n is 1,2,3, and 4, -0R5, or CH2OR5, where R5 is hydrogen or lower alkyl of from 1 to 4 carbon atoms; or a pharmaceutically acceptable salt thereof; have analgesic activity upon administration to warm-blooded animals. </p> |
