Synthesis Of Talipexole Hydrochloride

Talipexole hydrochloride is a new kind of drug for Parkinson's disease. It's chemical name is 6 -allyl- 2-amino- 5,6,7,8 -tetrahydro- 4H- thiazolo [4,5-d] azepine dihydrochloride. It's a non-ergot dopamine D2 receptor agonist. The anti-tremor effect of talipexole hydrochloride occurs at much lower doses than that of an ergot dopamine receptor agonist named bromocriptine. It improves symptoms of Parkinson's disease such as shaking of hands, muscle stiffness, slow movement and inability to maintain posture, and it also acts synergistically in combination with levodopa. In this paper it is designed a synthesis route with the knowledge based on document. Talipexole hydrochloride was synthesis from benzylamine by condensation with ethyl acrylate, followed by alkylation with ethyl 4-iodo butyrate, Dieckmann condensation, debenzylation, bromination, then cyclization with thiocarbamide, last alkylation with 3-bromopropene. This route is feasible with cheap material and high yield.