Factors affecting the lipase catalyzed transesterification reactions of 3-hydroxy esters in organic solvents.

verfasst von: Uwe Bornscheuer, Andrea Herar, Lars Kreye, Volker Wendel, Andreas Capewell, Hartmut H. Meyer, Thomas Scheper, Fragiskos N. Kolisis
Abstract: Chiral resolutions of racemic 3-hydroxy esters were performed in organic phases with lipases from Pseudomonas cepacia, Chromobacterium viscosum and Porcine pancreas. The reaction conditions have been optimized with 3-hydroxy octanoic acid methyl ester. Different organic solvents have been tested showing a tendentious correlation with the hydrophobicity of the solvents expressed as log P. The reaction time was shortened six fold by using irreversible acylating agents. We have found solvent type, lipase type and acylating agent acting as tools for changing the enantioselectivity. Lipase from Pseudomonas cepacia was lyophilized at different pH and the influence of the amount of water added was investigated, resulting in the highest activity at the pH optimum and a denaturation of the lipase above 1 % water (w/w_lipase). The water activity was measured on-line with a humidity sensor. Water activities greater than 0.4 led to a decrease in enantioselectivity and reaction rate. In the optimized system the resolutions of other 3-hydroxy esters were tested. Aliphatic compounds reacted with lower enantioselectivity, only the substrates could be isolated in high enantiomeric purity. In contrast, aromatic 3-hydroxy esters were acylated by lipases with high stereoselectivity. A model of the active site of lipase from Pseudomonas sp. explained these experimental observations.
Externe Organisation(en): Universität Nagoya
Westfälische Wilhelms-Universität Münster (WWU)
Nationale Technische Universität Athen (NTUA)
Typ: Artikel
Journal: Tetrahedron: Asymmetry
Band: 4
Seiten: 1007-1016
Anzahl der Seiten: 10
ISSN: 0957-4166
Publikationsdatum: 05.05.1993
Publikationsstatus: Veröffentlicht
Peer-reviewed: Ja
ASJC Scopus Sachgebiete: Katalyse, Physikalische und Theoretische Chemie, Organische Chemie, Anorganische Chemie
Elektronische Version(en): https://doi.org/10.1016/S0957-4166(00)80145-7 (Zugang: Unbekannt)

BibTeX

@article{dd358089315a42e591a8d060039b6bb8,
title = "Factors affecting the lipase catalyzed transesterification reactions of 3-hydroxy esters in organic solvents.",
abstract = "Chiral resolutions of racemic 3-hydroxy esters were performed in organic phases with lipases from Pseudomonas cepacia, Chromobacterium viscosum and Porcine pancreas. The reaction conditions have been optimized with 3-hydroxy octanoic acid methyl ester. Different organic solvents have been tested showing a tendentious correlation with the hydrophobicity of the solvents expressed as log P. The reaction time was shortened six fold by using irreversible acylating agents. We have found solvent type, lipase type and acylating agent acting as tools for changing the enantioselectivity. Lipase from Pseudomonas cepacia was lyophilized at different pH and the influence of the amount of water added was investigated, resulting in the highest activity at the pH optimum and a denaturation of the lipase above 1 % water (w/wlipase). The water activity was measured on-line with a humidity sensor. Water activities greater than 0.4 led to a decrease in enantioselectivity and reaction rate. In the optimized system the resolutions of other 3-hydroxy esters were tested. Aliphatic compounds reacted with lower enantioselectivity, only the substrates could be isolated in high enantiomeric purity. In contrast, aromatic 3-hydroxy esters were acylated by lipases with high stereoselectivity. A model of the active site of lipase from Pseudomonas sp. explained these experimental observations.",
author = "Uwe Bornscheuer and Andrea Herar and Lars Kreye and Volker Wendel and Andreas Capewell and Meyer, {Hartmut H.} and Thomas Scheper and Kolisis, {Fragiskos N.}",
year = "1993",
month = may,
day = "5",
doi = "10.1016/S0957-4166(00)80145-7",
language = "English",
volume = "4",
pages = "1007--1016",
journal = "Tetrahedron: Asymmetry",
issn = "0957-4166",
publisher = "Elsevier Ltd.",
number = "5",
}