Optically pure clopidogrel can be prepared in a high yield by optically resolving a racemic form of the compound of formula (II) using an optically active amine to form the optically active form of the compound of formula (III) or its acid-addition salt; and methylating the compound of formula (III) or its acid-addition salt.
通过使用手性活性胺来光学分离化合物II的外消旋体,形成化合物III或其酸加成盐的手性活性形式;并且甲基化化合物III或其酸加成盐,可以高产率地制备光学纯的
氯吡格雷。