7-(Trifluoromethyl)-4-aminoquinoline hypotensives: novel peripheral sympatholytics.

A family of 7-(trifluoromethyl)-4-aminoquinolines that are hypotensive agents and that act by a novel sympatholytic mechanism is described. Structure-activity relationships in this series have been elucidated. Some of the more potent hypotensives were evaluated for safety in the mouse. A candidate, 1-[(4-fluorophenyl)sulfonyl]-4-[4-[[7-(trifluoromethyl)-4- quinolinyl]amino]benzoyl]piperazine hydrochloride (losulazine hydrochloride) has been selected for clinical development. Losulazine hydrochloride is a hypotensive agent in the rat, cat, and dog. At acute effective hypotensive doses, it does not block the response of the sympathetic nervous system to stimuli. Both animal pharmacology and clinical experience suggest that losulazine hydrochloride may be free of the clinically limiting side effects that often plague compounds that decrease blood pressure by interfering with autonomic neurogenic function.