| abstract |
The invention provides trans-3,4 1-substituted-n3-substituted-4-methyl-4-(3-substituted phenyl)piperidines nas opioid antagonists capable of blocking the mu or kappa nreceptors in the brain, of the formula n nwherein: nR¹ is hydrogen or C₁-C₄ alkanoyl; nR² is hydrogen, C₁-C₄ alkyl or C₂-C₆ alkenyl; nR³ is C₄-C₈ cycloalkyl, C₄-C₈ cycloalkenyl, nC₁-C₆ alkyl, C₂-C₆ alkenyl, C₁-C₄ alkyl substituted nC₄-C₈ cycloalkyl, C₁-C₄ alkyl substituted C₄-C₈ ncycloalkenyl or thiophene; nZ is n n n- n- or a bond; nR⁴ is hydrogen, C₁-C₆ alkyl, n n nor - n-R⁵; nR⁵ is C₁-C₄ alkyl or n nn is 1, 2 or 3; or n a pharmaceutically acceptable salt thereof. |