52468-60-7

Flunarizine is the difluorinated derivative of cinnarizine. Thus, its preparation and therapeutic use are identical to those of cinnarizine.

Sibelium,Janssen,W. Germany,1977

Vasodilator.

ChEBI: Flunarizine is a diarylmethane.

A mixture of 14.3 parts of di-(p-fluorophenyl)-chloromethane, 10.1 parts of 1- cinnamylpiperazine, 12.7 parts of sodium carbonate, a few crystals of potassium iodide in 200 parts of 4-methyl-2-pentanone is stirred and refluxed for 21 hours. The reaction mixture is cooled and 50 parts of water are added. The organic layer is separated, dried, filtered and evaporated.
The oily residue is dissolved in 480 parts of anhydrous diisopropyl ether. This solution is boiled with activated charcoal, filtered and to the clear filtrate is added an excess of 2-propanol, previously saturated with gaseous hydrogen chloride. The precipitated salt is filtered off and recrystallized from a mixture of 2-propanol and ethanol, yielding 1-cinnamyl-4-(di-p-fluorobenzhydryl) piperazine dihydrochloride, MP 251.5°C.

Vasodilator

Flunarizine, an antihistaminic and vasodilator agent, was introduced into medicine in 1970. It is indicated for the treatment of central and peripheral vascular disorders. However, its effectiveness in these conditions has not been convincingly demonstrated, and its use has been associated with adverse reactions involving the central nervous system, including extrapyramidal disturbances and depression. This has led several regulatory authorities to restrict the approved indications for products containing flunarizine.