| abstract |
The invention provides methods for producing analgesia in an animal comprising administering to the animal a compound of the formula Ia′, Ib′, Ic′, and Id′: n n n n n n n n n n and pharmaceutically acceptable salts thereof, wherein the variables A, R 6 , R 7 , R 8 , R 9 , R x , L, X, Y, and Z have the meaning as described herein. |