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Enzymatic processes for the production of D-pantoyl lactone and related optically active hydroxylated compounds

用于生产 D-泛酰内酯和相关光学活性羟基化化合物的酶法

基本信息

批准号：
62560102
负责人：
SHIMIZU Sakayu
金额：
$ 1.28万
依托单位：
Kyoto University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1987
资助国家：
日本
起止时间：
1987 至 1988
项目状态：
已结题

项目摘要

The efficient enzymatic conversion of ketopantoyl lactone to D-(-)-pantoyl lactone was found to take place on incubation with washed cells of Candida parapsilosis IFO 0708 or Rhodotorula minuta IFO 0920. They showed high conversion activity when grown with 5% corn steep liquor and 5% glucose, sucrose,maltose or glycerol.Under suitable reaction conditions the amounts of D-(-)-pantoyl lactone reached 49.5g/l(94.4%e.e; molar yield,99%) and 89.9g/l(80.4%e.e; molar yield,99%)with cells of R.minuta and C.parapsilosis,respectively.A novel enzymatic process for the synthesis of D(-)-pantoyl lactone from a racemic mixture of pantoyllactone was also developed.The process involves the stereospecific oxidation of the L(+)-isomer of pantoyl lactoneto ketopantoyl lactone followed by its asymmetric reduction to the D(-)-isomer. The oxidation is carried out with cells of Nocardia asteroides AKU 2103 as the catalyst, which convert only the L(+)-isomer of pantoyl lactone to keto-pantoyl lactone without any modification of the remaining D(-)-isomer.With 80gl^<-1> DL-pantoyl lactone as the substrate,>90%of the added L(+)-isomer was converted to ketopantoyl lactone under the optimum reaction conditions. The ketopantoyl lactone that accumulated in the reaction mixture was almost specifically converted to the D(-)-isomer of pantoyl lactone on incubation with cells of Candida parapsilosis IFO 0784. Scince this process is simple and requires no reracemization step, which is necessary for conventional chemical resolution, it is highly advantageous for the practical synthesis of D(-)-pantoyl lactone.

发现酮基泛酰内酯向D-（-）-泛酰内酯的有效酶促转化在与近平滑假丝酵母IFO 0708或微小红酵母IFO 0920的洗涤细胞孵育时发生。在5%玉米浆和5%葡萄糖、蔗糖、麦芽糖或甘油的培养基中，D-（-）-泛解酸内酯的转化率最高，达49.5g/l（94.4%e. e;摩尔收率99%）和89.9g/l（80.4%e. e;摩尔产率为99%）与微小红球藻和近平滑红球藻的细胞，本论文还开发了一种从泛酰内酯的外消旋混合物合成D（-）-泛酰内酯的新的酶促方法，该方法包括立体特异性氧化L（+）-泛酰内酯异构体转化为酮基泛酰内酯，然后将其不对称还原为D（-）-异构体。以Nocardia asteroides AKU 2103细胞为催化剂，仅将泛酰内酯的L（+）-异构体转化为酮-泛酰内酯，其余D（-）-异构体不发生任何修饰，以80 μ l <-1>DL-泛酰内酯为底物，在最佳反应条件下，L（+）-异构体转化率> 90%。在与近平滑念珠菌IFO 0784细胞孵育时，在反应混合物中积累的酮基泛酰内酯几乎特异性转化为泛酰内酯的D（-）-异构体。由于该方法简单，不需要常规化学拆分所需的再外消旋步骤，因此非常有利于D（-）-泛解酰内酯的实际合成。