Compounds which function as melanocortin receptor ligands and having utility in the treatment of melanocortin receptor-based disorders. The compounds have the following structure (I): 1 including stereoisomers, prodrugs, and pharmaceutically acceptable salts thereof, wherein m, n, q, s, R.sub.1, R.sub.1a, R.sub.1b, R.sub.2, R.sub.3, R.sub.4, X.sub.1, X.sub.2 and X.sub.3 are as defined herein. Pharmaceutical compositions containing a compound of structure (I), as well as methods relating to the use thereof, are also disclosed.