practical applicability of this enzyme was evaluated for the reduction of ethyl 4-chloro-3-oxobutanoate (1a). Using Escherichia colicells coexpressing BYueD and glucose dehydrogenase, 215 gL−1 (1.3 M) of 1a was stoichiometrically converted to ethyl (R)-4-chloro-3-hydroxybutanoate ((R)-1b) in an aqueous-toluene biphasic system by using a substrate fed-batch strategy, resulting in an overall hydroxyl product
芽孢杆菌属的一个羰基还原酶基因(yueD)。ECU0013在大肠杆菌中异源过表达,并且将编码的蛋白质(BYueD)纯化至均质并进行了表征。NADPH依赖性还原酶对不同的芳族酮以及α-和β-酮酸酯显示出较宽的底物谱。尽管对于α-酮酯的还原,对映选择性高到中等,但是所有测试的β-酮酯和芳族酮均以对映体纯的形式还原为相应的手性醇。此外,评估了该酶的实际适用性,以减少4-氯-3-氧代丁酸乙酯(1a)。使用大肠杆菌细胞共表达BYueD和葡萄糖脱氢酶,将215 g L -1(1.3 M)的1a化学计量转化为(R)-4-氯-3-羟基丁酸乙酯((R)-1b)在水-甲苯双相体系中通过使用底物补料分批进料策略,产生的总羟基产物收率为91.7%,对映体纯度为99.6%ee。
Highly enantioselective double reduction of phenylglyoxal to ( R )-1-phenyl-1,2-ethanediol by one NADPH-dependent yeast carbonyl reductase with a broad substrate profile
作者:Zhe Li、Weidong Liu、Xi Chen、Shiru Jia、Qiaqiang Wu、Dunming Zhu、Yanhe Ma
DOI:10.1016/j.tet.2013.02.085
日期:2013.4
Pichia pastoris GS115 were evaluated with a series of carbonyl compounds including aryl aldehydes, ketones, α- and β-ketoesters. This recombinant enzyme possessed a broad substrate profile with the ability of reducing both aldehydes and ketones. Especially, the enzyme catalyzed the double reduction of phenylglyoxal to (R)-1-phenyl-1,2-ethanediol with 99% yield and 99% ee by coupling with d-glucose dehydrogenase
Efficient Reduction of Ethyl 2-Oxo-4-phenylbutyrate at 620 g⋅L−1 by a Bacterial Reductase with Broad Substrate Spectrum
作者:Yan Ni、Chun-Xiu Li、Jie Zhang、Nai-Dong Shen、Uwe T. Bornscheuer、Jian-He Xu
DOI:10.1002/adsc.201100132
日期:2011.5
A β‐ketoacyl‐ACP reductase (FabG) gene from Bacillus sp. ECU0013 was heterologously overexpressed in Escherichia coli and the encoded protein was purified to homogeneity. The recombinant reductase could reduce a broadspectrum of prochiral ketones including aromatic ketones and keto esters and showed the highest activity in the asymmetric reduction of ethyl 2‐oxo‐4‐phenylbutyrate (OPBE). Using E. coli
Compounds of formula Ia and Ib
wherein A, B, C and R
1
are described herein.
式Ia和Ib的化合物
其中A、B、C和R1
如本文所述。
Novel diphosphines, their complexes with transisition metals and their use in asymmetric synthesis
申请人:——
公开号:US20040260101A1
公开(公告)日:2004-12-23
The invention relates to novel diphosphines, in optically pure or racemic form, of formula (I):
1
in which:
R
1
and R
2
are a (C
5
-C
7
)cycloalkyl group, an optionally substituted phenyl group or a 5-membered heteroaryl group; and
A is (CH
2
—CH
2
) or CF
2
.
The invention further relates to the use of a compound of formula (I) as a ligand for the preparation of a metal complex useful as a chiral catalyst in asymmetric catalysis, and to the chiral metal catalysts comprising at least one ligand of formula (I).