The present invention discloses a method for preparing R-(+)-LA as well as its metal salts including sodium salt, potassium salt, calcium salt, magnesium salt, zinc salt, ferric salt, cooper salt , lithium salt and its organic salt, wherein a racemic Ethyl 6, 8-Dichlorooctanoic acid is employed as starting agents, followed by a hydrolysis and resolution processes to obtain (+)DCA, and then through sulfuration and cyclization process to obtain R-(+)-LA as well as its varied salts. A method for converting the (−)DCA to (+)DCA is also introduced.
本发明公开了一种制备R-(+)-
LA以及其
金属盐,包括钠盐、
钾盐、
钙盐、
镁盐、
锌盐、
铁盐、
铜盐、
锂盐和其有机盐的方法。该方法使用外消旋乙基6,8-二
氯辛酸作为起始剂,经过
水解和分离过程得到(+)DCA,然后通过
硫化和环化过程得到R-(+)-
LA及其各种盐。还介绍了一种将(-)DCA转化为(+)DCA的方法。