n-(4-tert-butylphenyl)-4-(3-chloropyridin-2-yl)tetrahydropyrazine-1(2h)-carboxamide and Fever

N-(4-Tert-butylphenyl)-4-(3-chloropyridin-2-yl) piperazine-1-carboxamide (BCTC) is a potent and extensively studied urea-based TRPV1 antagonist. Although BCTC was effective in alleviating chronic pain in rats, it showed obvious hyperthermia side-effect and unsatisfactory pharmacokinetic profile, therefore, it was not developed further. In order to enrich the structural types of urea-based TRPV1 antagonists, two series of novel analogs, in which the pyridine ring of BCTC was replaced with a mildly basic pyrimidine ring or 1,2,3,4-tetrahydro-β-carboline scaffold, were designed and synthesized. Advancing the structure-activity relationship of these two series led to the discovery of N-(4-methoxyphenyl)-1,3,4,9-tetrahydro-2H-pyrido[3,4-b]indole-2-carboxamide (7o), with an improved pharmacological and tolerability profile compared with the lead compound BCTC.

Topics: Analgesics; Animals; Dose-Response Relationship, Drug; Fever; Humans; Models, Molecular; Molecular Structure; Pyrazines; Pyridines; Rats; Structure-Activity Relationship; TRPV Cation Channels