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Ching-Shih Chen

Other affiliations: University of Rhode Island
Bio: Ching-Shih Chen is an academic researcher from University of Wisconsin-Madison. The author has contributed to research in topics: Enantioselective synthesis & Enantiomeric excess. The author has an hindex of 15, co-authored 24 publications receiving 4178 citations. Previous affiliations of Ching-Shih Chen include University of Rhode Island.

Papers
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TL;DR: The general catalytic properties of enzymes in nonaqueous environments are discussed, and the basic principles that govern lipase-catalyzed enantioselective esterification and transesterification reactions in organic media for the preparation of optically active acids and alcohols are explained.
Abstract: Enantioselective biocatalysis in nonaqueous media is becoming increasingly important in preparative synthetic chemistry. This article discusses (1) the general catalytic properties of enzymes in nonaqueous environments, (2) the basic principles that govern lipase-catalyzed enantioselective esterification and transesterification reactions in organic media for the preparation of optically active acids and alcohols, (3) the determination of kinetic and thermodynamic parameters, and (4) the quantitative analysis of published data.

589 citations

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TL;DR: The present progress report deals with the basic concepts that govern enantioselectivity of enzymes and intact cells and strategies to control the stereochemical course of microbial reductions of carbonyl compounds and the relationship of substrate structure to enantiOSElectivity.
Abstract: Microbial asymmetric reduction of ketones is a method widely used for the preparation of chiral alcohols. The present progress report deals with the basic concepts that govern enantioselectivity of enzymes and intact cells. Strategies to control the stereochemical course of microbial reductions of carbonyl compounds and the relationship of substrate structure to enantioselectivity are considered.

217 citations


Cited by
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Journal ArticleDOI
11 Jan 2001-Nature
TL;DR: The technological utility of enzymes can be enhanced greatly by using them in organic solvents rather than their natural aqueous reaction media, and they have found numerous potential applications, some of which are already commercialized.
Abstract: The technological utility of enzymes can be enhanced greatly by using them in organic solvents rather than their natural aqueous reaction media. Studies over the past 15 years have revealed not only that this change in solvent is feasible, but also that in such seemingly hostile environments enzymes can catalyse reactions impossible in water, become more stable, and exhibit new behaviour such as 'molecular memory'. Of particular importance has been the discovery that enzymatic selectivity, including substrate, stereo-, regio- and chemoselectivity, can be markedly affected, and sometimes even inverted, by the solvent. Enzyme-catalysed reactions in organic solvents, and even in supercritical fluids and the gas phase, have found numerous potential applications, some of which are already commercialized.

1,926 citations

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TL;DR: Roger Sheldon developed the concepts of E factors and atom utilization for assessing the environmental impact of chemical processes, particularly in relation to fine chemicals production.
Abstract: Roger Sheldon (1942) received a PhD in organic chemistry from the University of Leicester (UK) in 1967. This was followed by post-doctoral studies with Prof. Jay Kochi in the U.S. From 1969 to 1980 he was with Shell Research in Amsterdam and from 1980 to 1990 he was R&D Director of DSM Andeno. In 1991 he moved to his present position as Professor of organic chemistry and catalysis at the Delft University of Technology (The Netherlands). His primary research interests are in the application of catalytic methodologies—homogeneous, heterogeneous and enzymatic—in organic synthesis, particularly in relation to fine chemicals production. He developed the concepts of E factors and atom utilization for assessing the environmental impact of chemical processes.

1,567 citations

Journal ArticleDOI
TL;DR: Attention is focused on the factors that influence enzymatic catalysis in monophasic solvents including the role of enzyme-associated water, the nature of the biocatalyst preparation, and the properties of the organic solvent.

856 citations

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TL;DR: Esterases represent a diverse group of hydrolases catalyzing the cleavage and formation of ester bonds and are widely distributed in animals, plants and microorganisms and special emphasis is given on their application in organic synthesis for the resolution of racemates and prostereogenic compounds.
Abstract: Esterases (EC 3.1.1.x) represent a diverse group of hydrolases catalyzing the cleavage and formation of ester bonds and are widely distributed in animals, plants and microorganisms. Beside lipases, a considerable number of microbial carboxyl esterases have also been discovered and overexpressed. This review summarizes their properties and classification. Special emphasis is given on their application in organic synthesis for the resolution of racemates and prostereogenic compounds. In addition, recent results for altering their properties by directed evolution are presented.

834 citations