MatPhos,是完成艰苦任务的理想伴侣:迄今为止,由于中等ee值和低活性,阻碍了1-烷基乙烯基酯的不对称氢化,现在可以使用ee值为96–99%的MatPhos / Rh催化剂来实现在低催化剂负载量(0.1-1 mol%)和温和条件(5-20 bar H 2,室温)下制备底物。水解后,可以高对映体纯度获得相应的手性仲烷基醇,为获得这一重要产品类别提供了一条通用而实用的途径。
Highly Focused Library‐Based Engineering of
<i>Candida antarctica</i>
Lipase B with (
<i>S</i>
)‐Selectivity Towards
<i>sec</i>
‐Alcohols
作者:Yixin Cen、Danyang Li、Jian Xu、Qiongsi Wu、Qi Wu、Xianfu Lin
DOI:10.1002/adsc.201800711
日期:2019.1.11
reversed (S)‐selectivity towards a series of sec‐alcohol with E values up to 115 (conv. 50%, ee 94%). Compared with the previously reported (S)‐selective CALB variant, W104A, a single mutation provided less selectivity, while the synergistic effects of three mutations in the best variant endow better (S)‐selectivity and a broader substrate scope than the W104A variant. Structuralanalysis and molecular
Lipases SP525, AK, LIP, and PS were immobilized on three kinds of mesoporous silicates (FMS, PESO, and SBA) with diameters of 27 to 92 Å. The amount of lipase activity adsorbed on these supports was related to the pore size of the silicate. Enantioselectivities of immobilized lipases were similar to those of free lipases, and recycling could be done in both aqueous and organic solvents.
Discovery and Design of Family VIII Carboxylesterases as Highly Efficient Acyltransferases
作者:Henrik Müller、Simon P. Godehard、Gottfried J. Palm、Leona Berndt、Christoffel P. S. Badenhorst、Ann‐Kristin Becker、Michael Lammers、Uwe T. Bornscheuer
DOI:10.1002/anie.202014169
日期:2021.1.25
water, which enabled the synthesis of the drug moclobemide from methyl 4‐chlorobenzoate and 4‐(2‐aminoethyl)morpholine (ca. 20 % conversion). We solved the crystal structure of EstCE1 and detailed structure–function analysis revealed a three‐amino acid motif important for promiscuous acyltransferase activity. Introducing this motif into an esterase without acetyltransferase activity transformed a “hydrolase”
Ester Synthesis in Water: <i>Mycobacterium smegmatis</i>
Acyl Transferase for Kinetic Resolutions
作者:Nicolas de Leeuw、Guzman Torrelo、Carolin Bisterfeld、Verena Resch、Luuk Mestrom、Emanuele Straulino、Laura van der Weel、Ulf Hanefeld
DOI:10.1002/adsc.201701282
日期:2018.1.17
The acyl transferase from Mycobacterium smegmatis (MsAcT) catalyses transesterification reactions in aqueous media because of itshydrophobic active site. Aliphatic cyanohydrin and alkyne esters can be synthesised in water with excellent and strikingly opposite enantioselectivity [(R);E>37 and (S);E>100, respectively]. When using this enzyme, the undesired hydrolysis of the acyl donor is an important
Preparation of Passion Fruit-Typical 2-Alkyl Ester Enantiomers via Lipase-Catalyzed Kinetic Resolution
作者:Hedwig Strohalm、Susanne Dold、Kathrin Pendzialek、Monika Weiher、Karl-Heinz Engel
DOI:10.1021/jf100432s
日期:2010.5.26
fruit-typical 2-alkyl esters by capillary gas chromatography using heptakis(2,3-di-O-methyl-6-O-tert-butyldimethylsilyl)-β-cyclodextrin as chiral stationary phase. An efficient method was developed to prepare the ester enantiomers via lipase-catalyzed esterifications: optically pure (R)-2-alkyl esters (ee > 99.9%) were obtained by esterification of the racemic alcohols with enantioselective Candida antarctica
研究了通过脂肪酶催化动力学拆分制备仲醇2-戊醇,2-庚醇和2-壬醇的酯对映体(乙酸,丁酸酯,己酸酯和辛酸酯)。通过庚烷(2,3-di- O -methyl-6)的毛细管气相色谱法,对这些百香果类典型的2-烷基酯的同源系列进行了追踪,考察了市售酶制剂催化的酯化和水解反应的转化率和立体化学过程。- ø -叔丁基二)-β环糊精作为手性固定相。开发了一种通过脂肪酶催化的酯化反应制备酯对映体的有效方法:光学纯(R通过用对映选择性南极假丝酵母脂肪酶B(固定化)作为催化剂将外消旋醇酯化,可得到)-2-烷基酯(ee> 99.9%)。随后使用来自假丝酵母的脂肪酶将未反应的醇酯化,得到光学富集的(S)-酯(ee> 81.4%)。通过使用硅胶和氧化铝(碱性)的混合物的液体固体色谱法分离产物,得到高化学纯度和产率(> 40mol%)。