PROCESS FOR PRODUCING NATEGLINIDE CRYSTAL

摘要

A process for producing nateglinide crystals which comprises reacting trans-4-isopropylcyclohexylcarbonyl chloride with D-phenylalanine in a mixed solvent consisting of a ketone solvent and water in the presence of an alkali to obtain a reaction mixture containing nateglinide, adding an acid to the reaction mixture to make it acidic, and regulating the temperature and the ketone solvent concentration to 58 to 72 DEG C and 8 to 22 wt.%, excluding 8 and 22 wt.%, respectively, to thereby conduct crystallization. The process is an industrially advantageous method for crystallizing nateglinide.