Azetidinyl diamines useful as ligands of the nociceptin receptor ORL-1

A compound represented by the formula

• 171
• or a pharmaceutically acceptable salt or solvate thereof, or a diastereomer or enantiomer thereof, wherein:
• (a) R1 is —(CH2)nCHR4R5, fluorenyl, pyrimidinyl or
• 172
• n is 0, 1, 2 or 3;
• R2 is H;
• and R3 is —C(H)(R)—NR7R8;
• R is H, aryl, R6-aryl, aryl(CH2)1-2, R6-aryl(CH2)1-2 or heteroaryl;
• R4 is H, aryl, R6-aryl, heteroaryl, C1-6alkyl, C3-6 cycloalkyl or C2-6 alkenyl;
• R5 is aryl, R6-aryl, heteroaryl, C1-6 alkyl, C3-6 cycloalkyl, C2-6 alkenyl or fluorenyl, provided that when R4 and R5 are each phenyl, R is not phenyl or R6-phenyl;
• or R4 is H and R5 is tetrahydronaphthyl or tetrahydronaphthyl substituted with 1 or 2 substituents selected from the group consisting of halogen, C1-6 alkoxy, hydroxy, C1-6 alkyl and trihalo(C1-6)alkyl;
• R6 is 1 or 2 substituents independently selected from the group consisting of halogen, C1-6 alkoxy, hydroxy, phenyl, phenoxy, C1-6 alkyl, trihalo(C1-6)alkyl, amino, amido, —NO2, naphthyl, benzoyl and benzyloxy, or 2 adjacent ring carbon atoms can be substituted by methylenedioxy;
• R7 is —(CH2)xR9, tetrahydronaphthyl, tetrahydronaphthyl substituted with 1 or 2 R10 groups, or C5-C7 cycloalkyl;
• and R8 is H;
• or R7 and R8 together form a ring of the formula
• 173
• x is 0to 10;
• R9 is H, C1-C6 alkoxy, phenyl, phenyl substituted with 1 or 2 R10 groups, naphthyl, pyridyl, imidazolyl, furanyl, pyrrolidinyl, pyrrolidonyl, piperidinyl, N—(C1-C6 alkyl)-piperidinyl, N-aryl(C1-C6 alkyl)piperidinyl or diphenylmethyl;
• R10 is independently selected from the group consisting of halogen, C1-C6 alkoxy, C1-C6 alkyl, —OCF3 and methylenedioxy;
• R11 is aryl(C1-C6)alkyl, di-aryl(C1-C6)alkyl or piperidinyl;
• and
• R17 is H, C1-C6 alkyl or benzyl;
• or
• (b) R2is —NHR7 or
• 174
• and R3 is H;
• and
• R1 and R7 are as defined in (a).