A substituted piperazine compound having the structure I: or the structure IX: or an enantomeric, stereoisomeric or diastereomeric form of the foregoing, and pharmaceutically acceptable salts thereof, where J, L, Q, W, A, R6, R7, z and y are as defined in the specification, and the carbon atoms marked with an asterisk can have any stereochemical configuration, which compounds bind to one or more melanocortin receptors and may be employed in pharmaceutical preparations for treatment of one or more melanocortin receptor-associated conditions or disorders, and methods for the use of the compounds of the invention.