Synthesis and evaluation of new hydrazide derivatives as neuropeptide Y Y5 receptor antagonists for the treatment of obesity.

NPY is the most potent orexigenic agent known to man, with NPY Y1 and NPY Y5 being the receptor subtypes that are most likely responsible for centrally-mediated NPY-induced feeding responses. Based on the aforementioned, novel hydrazide derivatives were prepared for the purpose of searching new NPY Y5 receptor antagonists. Many of the compounds exhibited nanomolar binding affinity for this receptor, affording trans-N-(4-[N'-(3,4-dichlorophenyl)hydrazinocarbonyl]cyclohexylmethyl)-4-fluorobenzenesulfonamide, which showed the best activity (IC(50)=0.43nM).