OPTICAL RESOLUTION PROCESS FOR DL-CYSTEINE

摘要

A process for the optical resolution of DL-cysteine which comprises (1) converting DL-cysteine into a hydrochloride thereof and forming a saturated or supersaturated aqueous solution thereof, (2) inoculating the solution with crystals of one optically active form of cysteine hydrochloride as seed crystals, and (3) preferentially crystallizing optically the same form of the cysteine hydrochloride used as the seed crystals, in a state of a monohydrate thereof.