A process for preparing L-carnitine which comprises exposing .gamma.-substituted acetoacetic acid esters or amides to the fermentative enzymatic action of a microorganism which elaborates L-.beta.-hydroxyacyl CoA dehydrogenase [EC 1.1.1.35] , recovering the resulting, optically active corresponding .gamma.-substituted-.beta.-hydroxybutyric acid derivative and converting said derivative to L-carnitine. An improvement in the process is also disclosed which comprises reacting a 4-chloro-3(R)-hydroxybutyrate with sodium iodide or bromide to produce the corresponding 4-iodo- or 4-bromo-3(R)-hydroxybutyrate, converting the 4-iodo- or 4-bromo-3(R)-hydroxybutyrate to the trimethylamino-3(R)-hydroxybutyrate salt, then converting the trimethylamino-3(R)-hydroxybutyrate salt into L-carnitine. Novel chemical intermediates prepared in the processes are also disclosed.
一种制备
L-肉碱的方法,包括将.gamma.-取代
乙酰乙酸酯或酰胺暴露于微
生物的发酵酶作用下,该微
生物制造L-.beta.-羟基酰基
辅酶A脱氢酶[
EC 1.1.1.35],回收所得的光学活性对应的.gamma.-取代-.beta.-羟基
丁酸衍
生物,并将该衍
生物转化为
L-肉碱。还公开了一种改进方法,包括将4-
氯-3(R)-羟基
丁酸与
碘化钠或
溴化钠反应,以产生相应的4-
碘或4-
溴-3(R)-羟基
丁酸盐,将4-
碘或4-
溴-3(R)-羟基
丁酸盐转化为三甲基
氨基-3(R)-羟基
丁酸盐,然后将三甲基
氨基-3(R)-羟基
丁酸盐转化为
L-肉碱。还公开了在该过程中制备的新型
化学中间体。