PROCESS FOR PREPARING 2-METHYL-1,2,3,4,10,14B-HEXAHYDRO-DIBENZO (C,F)-PYRAZINO

摘要

This compound is known by the name of mianserine hydrochloride and finds application as an antidepressive and antihistamine agent in the medical practice. It is obtained at high yield rates and purity. The method comprises reacting 2-methyl-1,2,3,4,10,14b-hexahydro-dibenzo (c,f)-pyrazino (1,2-a)-azepine sulphate (mianserine sulphate) with calcium chloride at elevated temperatures in an aqueous medium, followed by hot isolation of the resulting calcium sulphate. This is followed by cooling the filtrate down to room temperature and isolating the crystallized mianserine hydrochloride.