A process for producing optically active cysteine derivatives with high optical purity and good quality which is economically advantageous and is high in productivity even on a commercial scale is provided.
A process for producing an optically active cysteine derivative which comprises synthesizing a D-form or L-form optically active cysteine derivative of the general formula (2) shown below (R
1
represents an amino-protecting group of the urethane or acyl type, R
0
represents a hydrogen atom or, taken together with R
1
, an amino-protecting group, R
2
represents an alkyl, aryl or aralkyl group, R
3
represents a univalent organic group and * represents the position of an asymmetric carbon) by reacting the corresponding D-form or L-form optically active amino acid derivative of the general formula (1) shown below with an alcohol of the general formula (3) shown below and a strong acid and/or a thionyl halide and recovering the above cysteine derivative (2) from the reaction mixture, the procedural series from reaction to recovery being carried out under conditions such that the medium contacting the above optically active cysteine derivative (2) is within the range from acidic to weakly basic to thereby recover the above cysteine derivative (2) from the reaction mixture while suppressing the decomposition and racemization thereof.
1
提供了一种生产高光学纯度和良好质量的光学活性半胱
氨酸衍
生物的工艺,该工艺在经济上具有优势,即使在商业规模上也具有高生产率。生产光学活性半胱
氨酸衍
生物的工艺包括通过将下面所示的一般式(1)的相应D型或L型光学活性
氨基酸衍
生物与下面所示的一般式(3)的醇和强酸和/或
硫酰卤反应合成下面所示的一般式(2)的D型或L型光学活性半胱
氨酸衍
生物(其中R1表示
脲或酰型
氨基保护基,R0表示氢原子或与R1一起表示
氨基保护基,R2表示烷基,芳基或芳基烷基,R3表示一价有机基团,*表示不对称碳的位置),并在其接触介质在酸性到微弱碱性范围内的条件下,从反应混合物中回收上述半胱
氨酸衍
生物(2),以抑制其分解和外消旋,从反应到回收的程序系列。