The invention relates to a process for the production of (R)- or (S)-8-chloro-6-hydroxyoctanoic acid alkyl esters of the general formula (R)-II or (S)-II,
1
in which R means C
1-4
alkyl, from 8-chloro-6-oxo-octanoic acid alkyl esters of the general formula I,
2
in which R has the above meaning.
The desired enantiomers are produced biocatalytically in an enantioselective reduction, wherein as desired the strains Mucor racemosus are used for (S)-II compounds and Geotrichum candidum for (R)-II compounds.
The resultant esters may, in known manner, be converted stereospecifically into (R)-&agr;-lipoic acid.
本发明涉及通式为(R)-II或(S)-II的(R)-或(S)-8-
氯-
6-羟基辛酸烷基酯的生产工艺、
1
其中 R 指 C
1-4
烷基,来自通式 I 的 8-
氯-6-氧代
辛酸烷基酯、
2
其中 R 具有上述含义。
所需的对映体是在对映体选择性还原中通过
生物催化产生的,其中(S)-II 化合物使用 Mucor racemosus 菌株,(R)-II 化合物使用 Geotrichum candidum 菌株。
所得
酯类可按已知方式立体定向转化为 (R)-&agr;-lipoic acid。