Compounds useful as modulators of melanocortin receptors and pharmaceutical compositions comprising same

A compound of formula (I),

• or a pharmaceutically-acceptable salt, hydrate, in which:
• X is N;
• R1 is hydrogen or C1-6alkyl;
• R2 is C1-6alkyl or C2-6alkenyl, each optionally substituted with aryl;
• E is E1 wherein
• G is selected from G is C2-4alkenyl, NHC(═O)R19, SO2R17, or when y is 0, G may also be pyrrolidinyl, piperidinyl, pyrrolidinyl(lower alkyl), or piperidinyl(lower alkyl);
• W is OH, —NH2, NH(lower alkyl), N(lower alkyl)2, azetidinyl, or imidazolyl, wherein the azetidinyl and imidazolyl are optionally substituted with lower alkyl;
• R4 and R7 are independently selected from hydrogen, alkyl, substituted alkyl, halogen, hydroxy, alkoxy, and keto;
• R5a, R5b, R6, R6a, R6b, R8 and R9 are independently hydrogen, halogen, cyano, alkyl, substituted alkyl, alkenyl, alkynyl, cycloakyl, heterocyclo, aryl, heteroaryl, —OR25, —NR25R26, —SR25, —S(O)pR26, —C(═O)R25, —OC(═O)R25, —CO2R25, —C(═O)NR25R26, —NR25C(═O)R26, —OC(═O)NR25R26, —NR25COR26, —NR27C(═O)NR25R26 or —NR25SO2R26;
• or R5a and R5b, R6a and R6b, or R8 and R9 taken together form a keto group (═C) or a monocyclic or bicyclic cycloalkyl or heterocyclo, or alternatively, R5a and/or R5b together with R8 and/or R9, or R6a and/or R6b together with R8 and/or R9, are taken to form a fused carbocyclic, heterocyclic, or heteroaryl ring;
• provided that,
• (1) R8 and R9 are other then hydrogen;
• and
• (2) when W is NH2 or NH (lower alkyl) and G is alkenyl, the R8 and R9 are other than hydrogen and at least one of R8 and R9 is other than alkyl, substituted alkyl, heterocyclo, aryl, heteroaryl, —OR25, —OC(═O)R25, —CO2R25, —C(═O)NR25R26, —NR25COR26, —NR27(C═O)NR25R26 or NR25SO2R26;
• R13, R14, R15 and R16 are selected independently of each other from hydrogen, alkyl, substituted alkyl, amino, alkylamino, hydroxy, alkoxy, aryl, cycloalkyl, heteroaryl, or heterocyclo, or R13 and R14, R15 and R16, when attached to the same carbon atom, may join to form a spirocyoloalkyl ring;
• R17 is alkyl or phenyl;
• R19 is alkyl or phenyl;
• R25, R26 and R27 are independently hydrogen, alkyl, substituted alkyl, cycloalkyl, aryl, heterocyclo, or heteroaryl;
• or R25 and R26 may join together to form a heterocyclic or heteroaryl, except R26 is not hydrogen when joined to a sulfonyl group as in —S(O)pR26 or —NR25SO2R26;
• p is 1, 2, or 3;
• x is 0, 1, or 2
• y is 0, 1, 2, 3 or 4;
• and
• z is 1.