OPTICALLY ACTIVE PIPERAZINE DERIVATIVE, ITS PRODUCTION AND CEREBRAL CIRCULATION IMPROVER CONTAINING THE SAME

摘要

NEW MATERIAL:(-)-1-(3,4-Dimethoxyphenyl)-2-(4-diphenylmethylpiperazinyl) ethanol of the formula (*represents an optically active carbon atom). USE:Cerebral circulation improver. It has excellent action to increase the blood flow rate in vertebrate animals, and is readily absorbed in the living bodies with reduced toxicity. PREPARATION:A mixture of optically active piperazine derivatives shown in the formula is allowed with an acidic optical resolution agent and the two kinds of diastereomers are resolved into the crystal and the solution utllizing their deference in solubility. Then, (-)-piperazine derivative or (+)-piperazine derivative is liberated from the separated diastereomer to collect an optically active piperazine derivative.