Synthesis and structure–activity relationships of biarylcarboxamide bis-aminopyrrolidine urea derived small-molecule antagonists of the melanin-concentrating hormone receptor-1 (MCH-R1)

A novel series of bis-aminopyrrolidine ureas containing either a 4-biphenylcarboxmide or 5-phenyl-2-thiophenecarboxamide group have been identified as potent and functional antagonists of the melanin-concentrating hormone receptor-1. Syntheses and SAR are described, which led to the discovery of compounds with high binding affinity (Ki = 1 nM) for the receptor. Preliminary in vitro metabolic stability data are also reported for key compounds.