| abstract |
PCT No. PCT/EP90/02011 Sec. 371 Date May 22, 1992 Sec. 102(e) Date May 22, 1992 PCT Filed Nov. 20, 1990 PCT Pub. No. WO91/08206 PCT Pub. Date Jun. 13, 1991.A compound, or solvate or salt thereof, of formula <IMAGE> wherein <IMAGE> <IMAGE> R2 and R3 are hydrogen or C1-6 alkyl; R5 together with R4 forms a -(CH)2)2- group optionally substituted by one or two C1-6 alkyl; W is halogen or when A is gem-dimethyl substituted piperidine, is OH; a is 1 or 2, useful in the treatment of pain. |