| 摘要 |
Compounds of the formula <IMAGE> and pharmaceutically acceptable non-toxic acid addition salts thereof, in which R is hydrogen, methyl, ethyl, cyclopropylmethyl, or allyl; A is a residue of a D-amino acid selected from the goup consisting of Ala, Abu, Nva, Val, Nle, Leu, Ile, Gly(Al), Gly(Cp) Met, Cys(Me), Met(O), Cys(Me) (O), Ser, Ser(Me), Thr, and Hse; R1 is hydrogen, C1-C3 primary alkyl, cyclopropylmethyl, allyl, ethylthiomethyl, 2-fluoroethyl, or propargyl; and X is hydrogen, fluoro, bromo, iodo, chloro, hydroxy, C1-C3 alkyl, trifluoromethyl, or C1-C2 alkoxy; are useful analgesic agents. |
