Melanin-concentrating hormone (MCH) receptor antagonists are disclosed having utility for the treatment of MCH receptor-based disorders such as obesity. The compounds of this invention have the following structure: 1 including stereoisomers, prodrugs, and pharmaceutically acceptable salts thereof, wherein R.sub.1, R.sub.2, R.sub.5, Het, X and Cyc are as defined herein. Also disclosed are compositions containing a compound of this invention, as well as methods relating to the use thereof.