MCH antagonists and their use in the treatment of obesity

A compound represented by the structural formula

• or a pharmaceutically acceptable salt, ester or solvate thereof, wherein
• W is R1—CR3R12NR4C(O)—;
• the dotted line is an optional double bond;
• X is —CHR8—, —C(O)—, —C(═NOR9)—, or, when the double bond is present, —CR8═;
• Y is
• or, when the double bond is present,
• R1 is R5—(C3-C8)cycloalkyl, R5—(C3-C8)cycloalkyl(C1-C8)alkyl, R5-aryl, R5-aryl-(C1-C6)alkyl, R5-heteroaryl, R5-heteroaryl(C1-C6)alkyl, R5-heterocycloalkyl or R5-heterocycloalkyl(C1-C6)alkyl;
• R2 is R6-aryl or R6-heteroaryl;
• n is 1, 2 or 3;
• R3 is C1-C6 alkyl, aryl or heteroaryl;
• R4 is H or C1-C6 alkyl;
• R5 is 1-4 substituents independently selected from the group consisting of H, C1-C6 alkyl, halogen, —OH, C1-C6 alkoxy, —CF3, (C1-C6)-alkoxycarbonyl, —SO2NHR4, —C(O)NHR4, —NR4C(O)NHR4, —NR4C(O)R4, —NR4SO2R4, R13-phenyl and naphthyl;
• R6 is 1-4 substituents independently selected from the group consisting of H, C1-C6 alkyl, halogen, —OH, —SH, —S(C1-C6 alkyl), —CN, C1-C6 alkoxy, C1-C6 alkylcarboxy, CF3, —NO2, —NH2, (C1-C6)alkylamino, phenyl, (C1-C6)-alkoxycarbonyl and R7-phenoxy, or adjacent ring carbon atoms form a ring with the group —O(CH2)1-2O—, —O(CH2)2-3— or —O(CF2)O—;
• R7 is 1-3 substituents independently selected from the group consisting of H, C1-C6 alkyl, halogen, —OH, C1-C6 alkoxy and CF3;
• R8 is H, C1-C6 alkyl or (C1-C4)alkoxy-(C1-C4)alkyl;
• R9 is H, C1-C6 alkyl or aryl-(C1-C4)alkyl;
• R10 is independently selected from the group consisting of H, C1-C6 alkyl and aryl;
• R12 is H or C1-C6 alkyl;
• and
• R13 is 1 to 3 substituents independently selected from the group consisting of H, C1-C6 alkyl, halogen, —OH, C1-C6 alkoxy, —CF3, —OCF3, —NO2 and —C(O)CH3.