| abstract |
The invention provides trans-3,4 1-substituted-3-substituted-4-methyl-4-(3-substituted phenyl)piperidines as opioid antagonists capable of blocking the mu or kappa receptors in the brain, of the formula <CHEM> wherein: R<1> is hydrogen or C1-C4 alkanoyl; R<2> is hydrogen, C1-C4 alkyl or C2-C6 alkenyl; R<3> is C4-C8 cycloalkyl, C4-C8 cycloalkenyl, C1-C6 alkyl, C2-C6 alkenyl, C1-C4 alkyl substituted C4-C8 cycloalkyl, C1-C4 alkyl substituted C4-C8 cycloalkenyl or thiophene; Z is <CHEM> - @- or a bond; R<4> is hydrogen, C1-C6 alkyl, <CHEM> or - @-R<5>; R<5> is C1-C4 alkyl or <CHEM> n is 1, 2 or 3; or a pharmaceutically acceptable salt thereof. |