There's No Industrial Biocatalyst Like Hydrolase:  Development of Scalable Enantioselective Processes Using Hydrolytic Enzymes¹

Abstract

Chiral, racemic esters, ethyl (()-tetrahydrofuran-2-carboxylate 4c, methyl (()-r-phenylpropionate 9b, methyl (()-5,5-dimethyl-1,3-thiazolidine-4-carboxylate 12a, 2-methoxyethyl (()-1-(4tert-butylphenyl)-2-oxopyrrolidine-4-carboxylate 15a, (()-1benzyloxy-3-chloropropan-2-yl hydrogen succinate 18c, and (()-3-butyryloxyquinuclidinium butyrate [(()-20b‚n-PrCO 2 H], are resolved kinetically by enantioselective hydrolysis catalyzed by an Aspergillus melleus protease [E ) 60; 93.9% ee and 35% yield for (R)-tetrahydrofuran-2-carboxylic acid 4a], a Klebsiella oxytoca hydrolase [E > 200; 99.5% ee and 36% yield for (S)r-phenylpropionic acid 9a], a K. oxytoca hydrolase [E ) 145; 97.7% ee and 34% yield for (R)-5,5-dimethyl-1,3-thiazolidine-4-carboxylic acid 12b], a Bacillus breWis protease [E ) 77; 99% ee and 45% yield for (S)-15a], a Serratia marcescence esterase [E ) 49; 99% ee and 43% yield for (S)-18c], and an A. melleus protease [E ) 96; 96% ee and 42% yield for (R)-20b], respectively. Each enzymatic process is discussed with focus on the following tactical issues: (1) identification of a hydrolase with high enantioselectivity, (2) substrate concentrations not less than 1 M that allow for industrially viable volume efficiency (spacetime yield), (3) product separation by partition between organic and aqueous phases, and (4) alleviation of a hydrolysate inhibiting the enzymatic activity.

Immobilisation and application of lipases in organic media

“…A key issue in the practical use of enantiomer resolution is the utilisation of not only the desired enantiomer, which is the product, but also the other enantiomer, which constitutes 50% of the starting material. 235 This can be achieved by batch-wise racemisation, but even better with continuous racemisation of Scheme 4 Lipase-catalysed reactions used for the resolution of the two enantiomers of a racemic alcohol. The two main products in each case are given in red (the reaction product and the remaining substrate).…”

Ex Situ Enantioconvergent Approaches for the Effective Use of Undesired­ Isomers: Stereochemical Convergence of a Substrate with Multiple Chiral Centers and Recycling of a Decarboxylated Byproduct

“…The two lipases are solid-supported enzymes that are highly stable in aqueous and organic solvents and can be easily removed from reaction mixtures by simple filtration. A. melleus protease has been developed for the modification of food properties by Nagase ChemteX Corporation (Japan) and applied in the kinetic resolution of ethyl tetrahydrofurancarboxylate and dihydropyridine derivatives, 30 which are structurally similar to 9a. In contrast to the sluggish hydro-…”

Degradation of Jatropha curcas phorbol esters derived from Jatropha oil cake and their tumor-promoting activity

“…SNSM87 is a heat-resistant esterase (Chikusa et al, 2003). KM109 can degrade bulky side chain unlike ordinary esterase which only degrades acetic ester or phosphate ester (Mitsuhashi et al, 1999).…”