153545-57-4

Upstream product

• 197158-51-3 (S)-Butyl 2-(4-ethylphenoxy)propionate 
• 308087-12-9 Butyl 2-(4-ethylphenoxy)propionate 
• 99761-31-6 (+/-)-2-(4-ethylphenoxy)propanoic acid 
• 71-36-3 butan-1-ol 

Downstream Products

• 197158-51-3 (S)-Butyl 2-(4-ethylphenoxy)propionate 

Relevant academic research and scientific papers

A great improvement of the enantioselectivity of lipase-catalyzed hydrolysis and esterification using co-solvents as an additive

Addition of co-solvents such as tetrahydrofuran resulted in a great improvement of the enantioselectivity of lipase-catalyzed hydrolysis of butyl 2-(4-substituted phenoxy)propanoates in an aqueous buffer solution. On the other hand, lipase lyophilized from an aqueous solution containing the co-solvents catalyzed highly enantioselective esterification of 2-(4-substituted phenoxy)propionic acids, 2-(4-isobutylphenyl)propionic acid (ibuprofen), and 2-(6-methoxy-2-naph-thyl)propionic acid (naproxen) in an organic solvent. An increase in the E value up to two orders of magnitude was observed for some substrates. The origin of the enantioselectivity enhancement caused by the co-solvent addition was mainly attributed to a significant deceleration in the initial reaction rate for the incorrectly binding enantiomer, as compared with that for the correctly binding enantiomer. From the results of FT-1R, CD, and ESR spectra, the co-solvent addition was also found to bring about a partial destruction of the tertiary structure of lipase.

Metal ions dramatically enhance the enantioselectivity for lipase-catalysed reactions in organic solvents

We propose a simple and a powerful method to enhance the enantioselectivity for lipase-catalysed transformations in organic solvents by an addition of metal ion-containing water to the reaction mixture. In this paper, various metal ions such as LiCl or MgCl2 are tested to improve the enantioselectivity for the model reactions. The enantioselectivities obtained are dramatically enhanced, the E values of which are about 100-fold as compared with the ordinary conditions without a metal ion, for example, E = 200 by addition of LiCl. Furthermore, lowering the reaction temperature led to an almost perfect enantioselectivity of lipase in the presence of a metal ion, for example, E = 1300 by addition of LiCl. Also, a mechanism for the drastic enhancement by metal ions is discussed briefly on the basis of the EPR spectroscopic study and the initial rate for each enantiomer of the substrate. The Royal Society of Chemistry 2006.

Flexibility of lipase brought about by solvent effects controls its enantioselectivity in organic media

The behavior of the enantioselectivity of Candida rugosa lipase was studied in the esterification of 2-(4-substituted phenoxy)propionic acids with 1-butanol in aliphatic, aromatic, and ethereal solvents, (cyclohexane, heptane, toluene, benzene, isooctane, dibutylether, etc.). Changing the solvent from cyclohexane to tert-butyl methyl ether, the isotropic signal increased quickly and the spectral line narrowed in width. The enzyme enantioselectivity in organic solvents was mainly controlled by its flexibility. The enantioselectivity of lipase in organic solvents was closely correlated with the lipase flexibility brought about by the cooperative solvent effects rather than with a sole solvent property, e.g., dielectric constant and hydrophobicity.

Dimethyl sulfoxide as a co-solvent dramatically enhances the enantioselectivity in lipase-catalysed resolutions of 2-phenoxypropionic acyl derivatives

We recently reported that the enantioselectivity for subtilisin-catalysed hydrolysis of ethyl 2-(4-substituted phenoxy)-propionates in aqueous buffer is found to be dramatically enhanced by addition of dimethyl sulfoxide (DMSO). In our present work, as one of the useful methods for improving the enzyme's enantioselectivity, this approach using DMSO is tested for both hydrolysis and transesterification catalysed by various lipases. For instance, for Candida rugosa lipase-catalysed hydrolysis in aqueous buffer containing DMSO, the optimum additive conditions (50-65 vol% DMSO) markedly enhance the enantioselectivity toward the substrates used, as compared with that for no-additive conditions, in spite of a decrease in the enzymatic activity. On the other hand, for Pseudomonas cepacia lipase-catalysed hydrolysis, the addition of DMSO to the reaction medium enhances the enantioselectivity with an increase in the enzymatic activity. Also, the DMSO effect on the enantioselectivity can apply to the lipase-catalysed transesterification in organic solvent. A mechanism for the DMSO-induced enhancement of the lipase's enantioselectivity is briefly discussed on the basis of the values of the initial rates obtained for each enantiomer of the substrate used.