Melanin-concentrating hormone receptor antagonists and compositions and methods related thereto

A compound having the following structure:

• or a stereoisomer, prodrug or pharmaceutically acceptable salt thereof,
• wherein:
• n is 0 or 1;
• R1 is hydrogen, alkyl, substituted alkyl, arylalkyl, substituted arylalkyl, heterocyclealkyl, substituted heterocyclealkyl, heterocycle, or substituted heterocycle;
• R2 is hydrogen, alkyl, substituted alkyl, —C(O)R7, or —S(O)2R8;
• or
• R1 and R2 together with the nitrogen to which they are attached form a heterocycle, optionally substituted with one or more R9;
• R3 is hydrogen, alkyl, or substituted alkyl;
• R4 is alkyl, substituted alkyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, heterocycle, or substituted heterocycle;
• R5 is hydrogen, alkyl, or substituted alkyl;
• R6 is hydrogen, alkyl, or substituted alkyl;
• R7 is hydrogen, alkyl, substituted alkyl, hydroxy, alkoxy, aryl, substituted aryl, heterocycle, or substituted heterocycle;
• R8 is hydrogen, alkyl, substituted alkyl;
• and
• R9 is alkyl, substituted alkyl, aryl, substituted aryl, hydroxy, or alkoxy.