Seventeen ammonium salts of fluorine-substituted benzhydryl aminoethyl ethers were synthesized and pharmacological properties of fifteen compounds were examined. Several compounds were found to suppress the tremor caused by harmine in mice. A dose of 30 mg/kg of 2-morpholinoethyl p-fluorobenzhydryl ether methylbromide (V) or 2-(1-pyrrolidinyl) ethyl p-chlorobenzhydryl ether methyliodide (IX) injected intraperitoneally had a more potent anti-harmine activity than the same dose of diphenhydramine, suggesting expectations of the drugs being active for Parkinsonism. Antihistaminic and anti-acetylcholine activities of the tested compounds in vitro were weaker than those of diphenhydramine and atropine respectively. As to the muscle relaxant activity, these compounds (1×10-5 g/ml) decreased acetylcholine (1×10-5)-induced contraction of frog rectus by 60 to 90%, and 1×10-5 to 3×10-5 decreased the twitches of the isolated frog sartorius elicited by nerve-stimulation. In the case of the whole animal however, intraperitoneal injection of 50 mg/kg of these compounds to mice did not show any remarkable sign.
