Journal articles: 'Enantioselective hydrolyses'

1

Glänzer, B. I., K. Faber, and H. Griengl. "Enantioselective hydrolyses by baker's yeast - II." Tetrahedron 43, no. 4 (1987): 771–78. http://dx.doi.org/10.1016/s0040-4020(01)90011-0.

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2

Tafi, Andrea, Andreas van Almsick, Federico Corelli, Maria Crusco, Kurt E. Laumen, Manfred P. Schneider, and Maurizio Botta. "Computer Simulations of Enantioselective Ester Hydrolyses Catalyzed byPseudomonas cepaciaLipase†." Journal of Organic Chemistry 65, no. 12 (June 2000): 3659–65. http://dx.doi.org/10.1021/jo9919198.

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3

Kasai, Masaji, Herman Ziffer, and J. V. Silverton. "Enantioselective ester hydrolyses using Rhizopusnigricans: stereoselective synthesis and absolute stereochemistry of (−)-cis- and (−)-trans-1-hydroxy-4-methyl-1,2,3,4-tetrahydronaphthalene." Canadian Journal of Chemistry 63, no. 6 (June 1, 1985): 1287–91. http://dx.doi.org/10.1139/v85-219.

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Enantioselective hydrolysis of racemic acetates of cis- and trans-1-hydroxy-4-methyl-1,2,3,4-tetrahydronaphthalene using Rhizopusnigricans yields chiral alcohols. The absolutestereochemistry of these compounds, and that of a key intermediate in their stereoselective synthesis, r-1-hydroxy-2,t-bromo-4,c-methyl-1,2,3,4-tetrahydronaphthalene, were determined by chemical transformations to 1-oxo-4-methyl-1,2,3,4-tetrahydronaphthalene of known absolute stereochemistry. The relativestereochemistry of the acetate of the key intermediate was established by X-ray crystallography.

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4

Xie, Zhuo-Feng, Izumi Nakamura, Hiroshi Suemune, and Kiyoshi Sakai. "An insight into the enantioselective hydrolyses of cyclic acetates catalysed by Pseudomonas fluorescens lipase." Journal of the Chemical Society, Chemical Communications, no. 14 (1988): 966. http://dx.doi.org/10.1039/c39880000966.

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5

Utsumi, Ryoichi, Shunsuke Izumi, and Toshifumi Hirata. "Enantioselective hydrolyses of α-methylated cyclohexyl acetates by the cultured cells of Marchantia polymorpha." Journal of Molecular Catalysis B: Enzymatic 11, no. 4-6 (January 2001): 439–43. http://dx.doi.org/10.1016/s1381-1177(00)00158-2.

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6

Deardorff, Donald R., Roberto B. Amador, James W. Morton, Henry Y. Kim, Cullen M. Taniguchi, Arnel A. Balbuena, Sam A. Warren, Vadim Fanous, and S. W. Tina Choe. "Chiral induction in cyclopentyl-derived 1,3-meso-diesters: enantioselective hydrolyses with electric eel acetylcholinesterase." Tetrahedron: Asymmetry 10, no. 11 (June 1999): 2139–52. http://dx.doi.org/10.1016/s0957-4166(99)00236-0.

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7

Csuk, René, and Petra Dörr. "Biocatalytical transformations. IV. Enantioselective enzymatic hydrolyses of building blocks for the synthesis of carbocyclic nucleosides." Tetrahedron: Asymmetry 5, no. 2 (January 1994): 269–76. http://dx.doi.org/10.1016/s0957-4166(00)86183-2.

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8

Fantin, Giancarlo, Marco Fogagnolo, Alessandra Guerrini, Alessandro Medici, Paola Pedrini, and Silvia Fontana. "Enantioselective hydrolyses with Yarrowia lipolytica: a versatile strain for esters, enol esters, epoxides, and lactones." Tetrahedron: Asymmetry 12, no. 19 (October 2001): 2709–13. http://dx.doi.org/10.1016/s0957-4166(01)00463-3.

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9

Gu, Rui-Lin, Ik-Soo Lee, and Charles J. Sih. "Chemo-enzymatic asymmetric synthesis of amino acids. Enantioselective hydrolyses of 2-phenyl-oxazolin-5-ones." Tetrahedron Letters 33, no. 15 (April 1992): 1953–56. http://dx.doi.org/10.1016/0040-4039(92)88111-h.

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10

Martinez-Rodríguez, Sergio, Rafael Contreras-Montoya, Jesús M. Torres, Luis Álvarez de Cienfuegos, and Jose Antonio Gavira. "A New L-Proline Amide Hydrolase with Potential Application within the Amidase Process." Crystals 12, no. 1 (December 23, 2021): 18. http://dx.doi.org/10.3390/cryst12010018.

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L-proline amide hydrolase (PAH, EC 3.5.1.101) is a barely described enzyme belonging to the peptidase S33 family, and is highly similar to prolyl aminopeptidases (PAP, EC. 3.4.11.5). Besides being an S-stereoselective character towards piperidine-based carboxamides, this enzyme also hydrolyses different L-amino acid amides, turning it into a potential biocatalyst within the Amidase Process. In this work, we report the characterization of L-proline amide hydrolase from Pseudomonas syringae (PsyPAH) together with the first X-ray structure for this class of L-amino acid amidases. Recombinant PsyPAH showed optimal conditions at pH 7.0 and 35 °C, with an apparent thermal melting temperature of 46 °C. The enzyme behaved as a monomer at the optimal pH. The L-enantioselective hydrolytic activity towards different canonical and non-canonical amino-acid amides was confirmed. Structural analysis suggests key residues in the enzymatic activity.

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11

Charton, Marvin, and Herman Ziffer. "Contributions of steric, electrical, and polarizability effects in enantioselective hydrolyses with Rhizopus nigricans: a quantitative analysis." Journal of Organic Chemistry 52, no. 12 (June 1987): 2400–2403. http://dx.doi.org/10.1021/jo00388a012.

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12

GU, R. L., I. S. LEE, and C. J. SIH. "ChemInform Abstract: Chemo-Enzymatic Asymmetric Synthesis of Amino Acids. Enantioselective Hydrolyses of 2-Phenyloxazolin-5-ones." ChemInform 23, no. 41 (August 21, 2010): no. http://dx.doi.org/10.1002/chin.199241230.

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13

Deardorff, Donald R., Roberto B. Amador, James W. Morton, Henry Y. Kim, Cullen M. Taniguchi, Arnel A. Balbuena, Sam A. Warren, Vadim Fanous, and S. W. Tina Choe. "ChemInform Abstract: Chiral Induction in Cyclopentyl-Derived 1,3-meso-Diesters: Enantioselective Hydrolyses with Electric Eel Acetylcholinesterase." ChemInform 30, no. 48 (June 12, 2010): no. http://dx.doi.org/10.1002/chin.199948046.

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14

Fantin, Giancarlo, Marco Fogagnolo, Alessandra Guerrini, Alessandro Medici, Paola Pedrini, and Silvia Fontana. "ChemInform Abstract: Enantioselective Hydrolyses with Yarrowia lipolytica: A Versatile Strain for Esters, Enol Esters, Epoxides, and Lactones." ChemInform 33, no. 22 (May 21, 2010): no. http://dx.doi.org/10.1002/chin.200222036.

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15

CSUK, R., and P. DOERR. "ChemInform Abstract: Biocatalytical Transformations. Part 4. Enantioselective Enzymatic Hydrolyses of Building Blocks for the Synthesis of Carbocyclic Nucleosides." ChemInform 25, no. 28 (August 19, 2010): no. http://dx.doi.org/10.1002/chin.199428066.

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16

Banerjee, Anirban, Praveen Kaul, Rohit Sharma, and U. C. Banerjee. "A High-Throughput Amenable Colorimetric Assay for Enantioselective Screening of Nitrilase-Producing Microorganisms Using pH Sensitive Indicators." Journal of Biomolecular Screening 8, no. 5 (October 2003): 559–65. http://dx.doi.org/10.1177/1087057103256910.

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Based on the color change of an indicator due to the release of hydrogen ion from a nitrilase-catalyzed reaction, a rapid colorimetric method was established for the enantioselective screening of nitrilase-producing microorganisms. The formation of acids due to the nitrilase-mediated hydrolysis of nitriles causes a drop in the pH, which in turn results in a change of color of the solution (containing indicator) that can be observed visually. The buffer (0.01 M phosphate, pH 7.2) and indicator (Bromothymol blue, 0.01%) were selected in such a way that both have the same affinity for the released protons. The enantioselectivity of nitrilases was estimated by comparing the hydrolysis of ( R)-mandelonitrile with that of racemate under the same conditions. The method was used to screen a library of nitrilase-producing microorganisms, isolated in the authors' laboratory for their ability to enantioselectively hydrolyze mandelonitrile to mandelic acid, an important chiral building block. ( Journal of Biomolecular Screening 2003:559-565).

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17

Naemura, Koichiro, Nobuo Takahashi, Shunsuke Tanaka, Michi Ueno, and Hiroaki Chikamatsu. "Enzyme-Catalyzed Enantioselective and Regioselective Hydrolyses of (2RS,7SR)-2,7-Diacetoxybicyclo[2.2.1]heptane and (2RS,7RS)-2,7-Diacetoxybicydo[2.2.1]heptane." Bulletin of the Chemical Society of Japan 63, no. 4 (April 1990): 1010–14. http://dx.doi.org/10.1246/bcsj.63.1010.

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18

Glänzer, B. I., K. Faber, and H. Griengl. "Enantioselective hydrolyses by baker's yeast - III11For part II Bee; B.I. Glänzer, K. Faber and H. Griengl, Tetrahedron 43, 771 (1987)." Tetrahedron 43, no. 24 (1987): 5791–96. http://dx.doi.org/10.1016/s0040-4020(01)87785-1.

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19

Zhang, Yan, Jiang Pan, Zheng-Jiao Luan, Guo-Chao Xu, Sunghoon Park, and Jian-He Xu. "Cloning and Characterization of a Novel Esterase from Rhodococcus sp. for Highly Enantioselective Synthesis of a Chiral Cilastatin Precursor." Applied and Environmental Microbiology 80, no. 23 (September 19, 2014): 7348–55. http://dx.doi.org/10.1128/aem.01597-14.

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ABSTRACTA novel nonheme chloroperoxidase (RhEst1), with promiscuous esterase activity for enantioselective hydrolysis of ethyl (S)-2,2-dimethylcyclopropanecarboxylate, was identified from a shotgun library ofRhodococcussp. strain ECU1013.RhEst1 was overexpressed inEscherichia coliBL21(DE3), purified to homogeneity, and functionally characterized. Fingerprinting analysis revealed thatRhEst1 preferspara-nitrophenyl (pNP) esters of short-chain acyl groups.pNP esters with a cyclic acyl moiety, especially that with a cyclobutanyl group, were also substrates forRhEst1. TheKmvalues for methyl 2,2-dimethylcyclopropanecarboxylate (DmCpCm) and ethyl 2,2-dimethylcyclopropane carboxylate (DmCpCe) were 0.25 and 0.43 mM, respectively.RhEst1 could serve as an efficient hydrolase for the bioproduction of optically pure (S)-2,2-dimethyl cyclopropane carboxylic acid (DmCpCa), which is an important chiral building block for cilastatin. As much as 0.5 M DmCpCe was enantioselectively hydrolyzed into (S)-DmCpCa, with a molar yield of 47.8% and an enantiomeric excess (ee) of 97.5%, indicating an extremely high enantioselectivity (E= 240) of this novel and unique biocatalyst for green manufacturing of highly valuable chiral chemicals.

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20

Chen, X. J., A. Archelas, and R. Furstoss. "Microbiological transformations. 27. The first examples for preparative-scale enantioselective or diastereoselective epoxide hydrolyses using microorganisms. An unequivocal access to all four bisabolol stereoisomers." Journal of Organic Chemistry 58, no. 20 (September 1993): 5528–32. http://dx.doi.org/10.1021/jo00072a043.

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21

ARAND, Michael, Frank MÜLLER, Astrid MECKY, Willy HINZ, Phillipe URBAN, Denis POMPON, Roland KELLNER, and Franz OESCH. "Catalytic triad of microsomal epoxide hydrolase: replacement of Glu404 with Asp leads to a strongly increased turnover rate." Biochemical Journal 337, no. 1 (December 17, 1998): 37–43. http://dx.doi.org/10.1042/bj3370037.

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Microsomal epoxide hydrolase (mEH) belongs to the superfamily of α/β-hydrolase fold enzymes. A catalytic triad in the active centre of the enzyme hydrolyses the substrate molecules in a two-step reaction via the intermediate formation of an enzyme-substrate ester. Here we show that the mEH catalytic triad is composed of Asp226, Glu404 and His431. Replacing either of these residues with non-functional amino acids results in a complete loss of activity of the enzyme recombinantly expressed in Saccharomyces cerevisiae. For Glu404 and His431 mutants, their structural integrity was demonstrated by their retained ability to form the substrate ester intermediate, indicating that the lack of enzymic activity is due to an indispensable function of either residue in the hydrolytic step of the enzymic reaction. The role of Asp226 as the catalytic nucleophile driving the formation of the ester intermediate was substantiated by the isolation of a peptide fraction carrying the 14C-labelled substrate after cleavage of the ester intermediate with cyanogen bromide. Sequence analysis revealed that one of the two peptides within this sample harboured Asp226. Surprisingly, the replacement of Glu404 with Asp greatly increased the Vmax of the enzyme with styrene 7,8-oxide (23-fold) and 9,10-epoxystearic acid (39-fold). The increase in Vmax was paralleled by an increase in Km with both substrates, in line with a selective enhancement of the second, rate-limiting step of the enzymic reaction. Owing to its enhanced catalytic properties, the Glu404 → Asp mutant might represent a versatile tool for the enantioselective bio-organic synthesis of chiral fine chemicals. The question of why all native mEHs analysed so far have a Glu in place of the acidic charge relay residue is discussed.

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22

CHEN, X. J., A. ARCHELAS, and R. FURSTOSS. "ChemInform Abstract: Microbiological Transformations. Part 27. The First Examples for Preparative-Scale Enantioselective or Diastereoselective Epoxide Hydrolyses Using Microorganisms. An Unequivocal Access to All Four Bisabolol Stereoisomers." ChemInform 25, no. 7 (August 19, 2010): no. http://dx.doi.org/10.1002/chin.199407058.

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23

Tang, Feng Xiang, Yun Bo Li, Chun Meng, and Xue Qing Zhao. "A Two-Step Resolution for Preparing Enantiopure (S)-Ethyl Nipecotate." Advanced Materials Research 393-395 (November 2011): 559–66. http://dx.doi.org/10.4028/www.scientific.net/amr.393-395.559.

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Enantiopure nipecotic acid or ethyl nipecotate are key precursors for synthesizing a variety of pharmaceutically important compounds. In this work a two-step resolution of racemic ethyl nipecotate was developed to prepare enantiopure (S)-ethyl nipecotate. In the enzymatic resolution step, six lipases were screened for their ability to enantioselectively hydrolyze rac-ethyl nipecotate in t-butanol at 30°C and Novozym 435 was found to be the most effective. Solvent effects on the hydrolysis conversion and enantioselectivity showed that water was the optimum medium. When rac-ethyl nipecotate concentration was kept at 0.5M, the hydrolysis under optimum conditions (lipase loading 5mg/mL, phosphate buffer pH 7.0, reaction temperature 30°C, reaction time 6h) afforded 68.9% ees and 69.5% eep at 49.8% conversion. Novozym 435 preferentially hydrolyzed (R)-ethyl nipecotate over (S)-enantiomer. A parallel reaction model was suggested and found to fit the experimental initial rate data very well. (S)-enriched ethyl nipecotate was further resolved using (D)-tartaric acid and enantiopure (S)-ethyl nipecotate (98.5% ee) was acquired in 84.3% yield. The overall yield of enantiopure (S)-ethyl nipecotate by this two-step resolution was up to 36.0%.

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24

Majewska, Paulina. "Lipase-Catalyzed Kinetic Resolution of Dimethyl and Dibutyl 1-Butyryloxy-1-carboxymethylphosphonates." Catalysts 11, no. 8 (August 10, 2021): 956. http://dx.doi.org/10.3390/catal11080956.

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The main objective of this study is the enantioselective synthesis of carboxyhydroxyphosphonates by lipase-catalyzed reactions. For this purpose, racemic dimethyl and dibutyl 1-butyryloxy-1-carboxymethylphosphonates were synthesized and hydrolyzed, using a wide spectrum of commercially available lipases from different sources (e.g., fungi and bacteria). The best hydrolysis results of dimethyl 1-butyryloxy-1-carboxymethylphosphonate were obtained with the use of lipases from Candida rugosa, Candida antarctica, and Aspergillus niger, leading to optically active dimethyl 1-carboxy-1-hydroxymethylphosphonate (58%–98% enantiomeric excess) with high enantiomeric ratio (reaching up to 126). However, in the case of hydrolysis of dibutyl 1-butyryloxy-1-carboxymethylphosphonate, the best results were obtained by lipases from Burkholderia cepacia and Termomyces lanuginosus, leading to optically active dibutyl 1-carboxy-1-hydroxymethylphosphonate (66%–68% enantiomeric excess) with moderate enantiomeric ratio (reaching up to 8.6). The absolute configuration of the products after biotransformation was also determined. In most cases, lipases hydrolyzed (R) enantiomers of both compounds.

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25

Loandos, María del H., Ana C. Muro, Margarita B. Villecco, Marcelo F. Masman, Paul G. M. Luiten, Sebastian A. Andujar, Fernando D. Suvire, and Ricardo D. Enriz. "Catalytic and Molecular Properties of Rabbit Liver Carboxylesterase Acting on 1,8-Cineole Derivatives." Natural Product Communications 7, no. 9 (September 2012): 1934578X1200700. http://dx.doi.org/10.1177/1934578x1200700901.

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Rabbit liver carboxylesterase (rCE) was evaluated as the catalyst for the enantioselective hydrolysis of (±)-3-endo-acetyloxy-1,8-cineole [(±)-4], which yields (1S,3S,4R)-(+)-3-acetyloxy-1,8-cineole [(+)-4] and (1R,3R,4S)-(-)-3-hydroxy-1,8-cineole [(-)-3]. Enantioselective asymmetrization of meso-3,5-diacetoxy-1,8-cineol (5) gives (1S,3S,4R,5R)-(-)-3-acetyloxy-5-hydroxy-1,8-cineole (6), with high enantioselectivity. rCE has been chosen to perform both experiments and molecular modeling simulations. Docking simulations combined with molecular dynamics calculations were used to study rCE-catalyzed enantioselective hydrolysis of cineol derivatives. Both compounds were found to bind with their acetyl groups stabilized by hydrogen bond interactions between their oxygen atoms and Ser221.

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26

Chênevert, Robert, and Martin Létourneau. "Enantioselectivity of carbonic anhydrase catalyzed hydrolysis of mandelic methyl esters." Canadian Journal of Chemistry 68, no. 2 (February 1, 1990): 314–16. http://dx.doi.org/10.1139/v90-044.

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We report the first enantioselective hydrolysis of esters catalyzed by carbonic anhydrase. We found that mandelic methyl esters are good substrates for carbonic anhydrase. The R enantiomers are better substrates and enantiomeric excess values are moderate (40–51%). Keywords: carbonic anhydrase, mandelic esters, enantioselectivity, hydrolysis.

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27

Leśniarek, Aleksandra, Anna Chojnacka, and Witold Gładkowski. "Application of Lecitase® Ultra-Catalyzed Hydrolysis to the Kinetic Resolution of (E)-4-phenylbut-3-en-2-yl Esters." Catalysts 8, no. 10 (September 28, 2018): 423. http://dx.doi.org/10.3390/catal8100423.

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The possibility of using Lecitase® Ultra as a novel alternative biocatalyst for the kinetic resolution of model racemic allyl esters of (E)-4-phenylbut-3-en-3-ol: Acetate (4a) and propionate (4b) through their enantioselective hydrolysis was investigated. Reaction afforded (+)-(R)-alcohol (3) and unreacted (−)-(S)-ester (4a or 4b). Hydrolysis of propionate 4b proceeded with higher enantioselectivity than acetate 4a. (R)-Alcohol (3) with highest enantiomeric excess (93–99%) was obtained at 20–30 °C by hydrolysis of propionate 4b, while the highest optical purity of unreacted substrate was observed for (S)-acetate 4a (ee = 34–56%). The highest enantioselectivity was found for the hydrolysis of propionate 4b catalyzed at 30 °C (E = 38). Reaction carried out at 40 °C significantly lowered enantiomeric excess of produced alcohol 3 and enantioselectivity in resolution. Lecitase® Ultra catalyzed the enantioselective hydrolysis of allyl esters 4a,b according to Kazlauskas’ rule to produce (R)-alcohol 3 and can find application as a novel biocatalyst in the processes of kinetic resolution of racemic allyl esters.

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28

Loandos, María del H., Margarita B. Villecco, Eleuterio Burgueño-Tapia, Pedro Joseph-Nathan, and César A. N. Catalán. "Preparation and Absolute Configuration of (1R,4R)-(+)-3-Oxo-, (1S,4S)-(-)-3-Oxo- and (1R,3S,4R)-(+)-3-Acetyloxy-5-oxo-1,8-cineole." Natural Product Communications 4, no. 11 (November 2009): 1934578X0900401. http://dx.doi.org/10.1177/1934578x0900401116.

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Enantiomerically pure (1S,4S)-(-)-3-oxo-1,8-cineole (-)-2 and (1R,4R)-(+)-3-oxo-1,8-cineole (+)-2 were prepared for the first time and their absolute configurations assigned by vibrational circular dichroism (VCD) measurements. Thus, treatment of cineole 1 with chromyl acetate gave rac-2 which after sodium borohydride reduction and acetylation provided racemic 3-endo-acetyloxy-1,8-cineole, rac-4. Enantioselective hydrolysis using porcine liver esterase (PLE) gave a mixture of 3-endo-hydroxy-1,8-cineole (-)-3 and 3-endo-acetyloxy-1,8-cineole (+)-4. After chromatographic separation, (-)-3 was oxidized to (+)-2, while (+)-4 was hydrolysed to (+)-3 and then oxidized to (-)-2. The absolute configuration of either ketone 2 was established by VCD spectroscopy in combination with density functional theory (DFT) calculations at the B3LYP/DGDZVP level of theory, from where it followed that the (+)-2 enantiomer corresponds to (1R,4R)-1,3,3-trimethyl-5-oxo-2-oxabicyclo[2.2.2]octane and the (-)-2 enantiomer to the (1S,4S) molecule which is also in agreement with the absolute configuration deduced by the Mosher method for the starting chiral alcohols. Some literature inconsistencies are clarified. In addition, the enantiomerically pure monoester (1S,3S,4R,5R)-(-)-3-acetyloxy-5-hydroxy-1,8-cineole 6 and the ketoester (1R,3S,4R)-(+)-3-acetyloxy-5-oxo-1,8-cineole 7 were prepared from meso-diacetate 5 by enantioselective asymmetrization also using PLE.

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29

Trott, Sandra, Sibylle Bürger, Carsten Calaminus, and Andreas Stolz. "Cloning and Heterologous Expression of an Enantioselective Amidase from Rhodococcus erythropolis Strain MP50." Applied and Environmental Microbiology 68, no. 7 (July 2002): 3279–86. http://dx.doi.org/10.1128/aem.68.7.3279-3286.2002.

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ABSTRACT The gene for an enantioselective amidase was cloned from Rhodococcus erythropolis MP50, which utilizes various aromatic nitriles via a nitrile hydratase/amidase system as nitrogen sources. The gene encoded a protein of 525 amino acids which corresponded to a protein with a molecular mass of 55.5 kDa. The deduced complete amino acid sequence showed homology to other enantioselective amidases from different bacterial genera. The nucleotide sequence approximately 2.5 kb upstream and downstream of the amidase gene was determined, but no indications for a structural coupling of the amidase gene with the genes for a nitrile hydratase were found. The amidase gene was carried by an approximately 40-kb circular plasmid in R. erythropolis MP50. The amidase was heterologously expressed in Escherichia coli and shown to hydrolyze 2-phenylpropionamide, α-chlorophenylacetamide, and α-methoxyphenylacetamide with high enantioselectivity; mandeloamide and 2-methyl-3-phenylpropionamide were also converted, but only with reduced enantioselectivity. The recombinant E. coli strain which synthesized the amidase gene was shown to grow with organic amides as nitrogen sources. A comparison of the amidase activities observed with whole cells or cell extracts of the recombinant E. coli strain suggested that the transport of the amides into the cells becomes the rate-limiting step for amide hydrolysis in recombinant E. coli strains.

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30

Jammer, S., D. Rizkov, F. Gelman, and O. Lev. "Quantitative structure–activity relationship correlation between molecular structure and the Rayleigh enantiomeric enrichment factor." Environmental Science: Processes & Impacts 17, no. 8 (2015): 1370–76. http://dx.doi.org/10.1039/c5em00084j.

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The enantiomeric enrichment caused by enzymatic enantioselective hydrolysis is studied for a homologous series, revealing a correlation between substrate molecular features and the Rayleigh enantiomeric enrichment factor,ε_ER.

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31

T. Mohd Ali, M., and . "Synthesis of -Hydroxy -Proline: Potential for Organocataly-sis Reactions." International Journal of Engineering & Technology 7, no. 4.14 (December 24, 2019): 237. http://dx.doi.org/10.14419/ijet.v7i4.14.27571.

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A chiral organic molecule, L-proline catalyzed an enantioselective transformation reaction has becoming interesting synthetic protocol especially in the area of organocatalysis. Herein, a synthetic approach towards -hydroxy--proline starting from bicyclic lactone lactam is hereby described. The syntheses utilized dicarboxylation reaction of bicyclic lacton lactam, followed by ether hydrolysis of the bicyclic ether and oxidation reaction of the primary alcohol. The synthetic strategy disclosed here allows further the enantioselective synthesis of a variety of unnatural amino acids based on -proline structure.

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32

Sinha, Subhash C., Ehud Keinan, and Jean Louis Reymond. "Antibody-catalyzed enantioselective epoxide hydrolysis." Journal of the American Chemical Society 115, no. 11 (June 1993): 4893–94. http://dx.doi.org/10.1021/ja00064a061.

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33

Glänzer, B. I., K. Faber, and H. Griengl. "Enantioselective hydrolysis by baker's yeast." Tetrahedron Letters 27, no. 36 (1986): 4293–94. http://dx.doi.org/10.1016/s0040-4039(00)94256-4.

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34

Liu, Xue Ying, Hong Yan Zeng, Deng Hong Peng, Bi Foua Claude Alain Gohi, Qing Jun Huang, Chao Yu, and Yu Qin Li. "Molecular Docking Studies on the Interaction of 2-Arylpropionate Esters with Candida rugosa Lipase." Applied Mechanics and Materials 496-500 (January 2014): 520–23. http://dx.doi.org/10.4028/www.scientific.net/amm.496-500.520.

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The interaction between ethyl 2-arylpropiolates and Candida rugosa lipase was studied by enantioselective hydrolysis and molecular docking. The ethyl 2-arylpropiolates with the lowest binding energy was selected to investigate the molecular mechanism of enzyme mediated asymmetric catalysis mechanism.

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35

Jin, Jian Zhong, and Jie Zhang. "Highly Enantioselective Hydrolysis of Racemic Isopropyl Tert-Leucinate by Newly Discovered Baclicus Lincheniformis Jx010 for Synthesis of L-Tert-Butyl Leucine." Advanced Materials Research 343-344 (September 2011): 453–56. http://dx.doi.org/10.4028/www.scientific.net/amr.343-344.453.

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Newly discovered strain Baclicus lincheniformis JX010 was identified to enantioselective hydrolysis of racemic ethyl tert-leucinate for the synthesis of chiral L-tert-butyl leucine. In the hydrolysis of isopropyl tert-butyl leucinate, the L-tert-butyl leucine was synthesized in 99% ee and 48% conversion. The cells was immobilized on synthetic resin 0501 without pretreatment to increase the enzyme stability. A series of organic cosolvents were investigated the hydrolysis rate and 2% glycerol was considered as the optimized cosolvent. In the hydrolysis of 50 mM isopropyl tert-butyl leucinate, the immobilized cells remained 85%activity with L-tert-butyl leucine in 99% ee after 8 reaction cycles.

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36

Toone, Eric J., and J. Bryan Jones. "Enzymes in organic synthesis. 40. Evaluation of the enantioselectivity of the pig liver esterase catalyzed hydrolyses of racemic piperidine carboxylic acid esters." Canadian Journal of Chemistry 65, no. 12 (December 1, 1987): 2722–26. http://dx.doi.org/10.1139/v87-452.

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37

Matsumoto, Takashi, Mio Ochiai, Yuki Akisawa, and Daichi Kajiyama. "Desymmetrization of σ-Symmetric Biphenyl-2,6-diyl Diacetate Derivatives by Lipase-Catalyzed Hydrolysis: Unexpected Effect of C(3′)-Substituent on the Enantiotopic Group Selectivity." Synlett 30, no. 05 (January 4, 2019): 557–62. http://dx.doi.org/10.1055/s-0037-1611701.

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Highly enantioselective desymmetrization of σ-symmetric 3′-substituted 2′,6′-dimethoxybiphenyl-2,6-diyl diacetate derivatives to the corresponding monoacetates was effected by using Rhizopus oryzae lipase (ROL) and porcine pancreatic lipase (PPL), despite the remoteness of the C(3′) substituent from the acetate groups. ROL promoted hydrolysis of the pro-S acetates, irrespective of the type of C(3′) substituent, whereas PPL promoted hydrolysis of the pro-R acetates, and selectivity was only attainable when the C(3′) substituent was a polar group.

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38

Mączka, Wanda K., and Agnieszka Mironowicz. "Enantioselective Hydrolysis of Bromo- and Methoxy-Substituted 1-Phenylethanol Acetates Using Carrot and Celeriac Enzymatic Systems." Zeitschrift für Naturforschung C 62, no. 5-6 (June 1, 2007): 397–402. http://dx.doi.org/10.1515/znc-2007-5-613.

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Enantioselective hydrolysis of bromo- and methoxy-substituted 1-phenylethanol acetates was conducted using comminuted carrot (Daucus carota L.) and celeriac (Apium graveolens L. var. rapaceum) roots. Hydrolysis of the acetates led to alcohols, preferentially to R-(+)- enantiomers. Efficiencies of both reactions - hydrolysis of the acetates with an electrondonating methoxy group and oxidation of the resulting alcohols - increased in the following order: ortho < meta < para. The presence of an electron-withdrawing bromine atom in the aromatic ring had the opposite effect. Oxidation of alcohols with both types of substituents in the aromatic ring showed that location of a substituent had stronger impact on the oxidation rate than its electronic properties.

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39

Shen, Duan, Jian-He Xu, Peng-Fei Gong, Hui-Yuan Wu, and You-Yan Liu. "Isolation of an esterase-producing Trichosporon brassicae and its catalytic performance in kinetic resolution of ketoprofen." Canadian Journal of Microbiology 47, no. 12 (December 1, 2001): 1101–6. http://dx.doi.org/10.1139/w01-121.

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A yeast strain CGMCC 0574, identified as Trichosporon brassicae, was selected from 92 strains for its high (S) selectivity in the hydrolysis of ketoprofen ethyl ester. The effective strains of the microorganisms were isolated from soil samples with the ester as the sole carbon source. The ethyl ester proved to be the best substrate for resolution of ketoprofen among several ketoprofen esters examined. The resting cells of CGMCC 0574 could catalyze the hydrolysis of ketoprofen ethyl ester with an enantiomeric ratio of 44.9, giving (S)-ketoprofen an enantiomeric excess of 91.5% at 42% conversion.Key words: ketoprofen, biocatalytic resolution, enantioselective hydrolysis, microbial esterase, Trichosporon brassicae.

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40

Roura Padrosa, David, Valerio De Vitis, Martina Contente, Francesco Molinari, and Francesca Paradisi. "Overcoming Water Insolubility in Flow: Enantioselective Hydrolysis of Naproxen Ester." Catalysts 9, no. 3 (March 3, 2019): 232. http://dx.doi.org/10.3390/catal9030232.

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Hydrolytic enantioselective cleavage of different racemic non-steroidal anti-inflammatory drugs (NSAIDs) ester derivatives has been studied. An engineered esterase form Bacillus subtilis (BS2m) significantly outperformed homologous enzymes from Halomonas elongata (HeE) and Bacillus coagulants (BCE) in the enantioselective hydrolysis of naproxen esters. Structural analysis of the three active sites highlighted key differences which explained the substrate preference. Immobilization of a chimeric BS2m-T4 lysozyme fusion (BS2mT4L1) was improved by resin screening achieving twice the recovered activity (22.1 ± 5 U/g) with respect to what had been previously reported, and was utilized in a packed bed reactor. Continuous hydrolysis of α-methyl benzene acetic acid butyl ester as a model substrate was easily achieved, albeit at low concentration (1 mM). However, the high degree of insolubility of the naproxen butyl ester resulted in a slurry which could not be efficiently bioconverted, despite the addition of co-solvents and lower substrate concentration (1 mM). Addition of Triton® X-100 to the substrate mix yielded 24% molar conversion and 80% e.e. at a 5 mM scale with 5 min residence time and sufficient retention of catalytic efficiency after 6 h of use.

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41

Gadler, P., S. M. Glueck, W. Kroutil, B. M. Nestl, B. Larissegger-Schnell, B. T. Ueberbacher, S. R. Wallner, and K. Faber. "Biocatalytic approaches for the quantitative production of single stereoisomers from racemates." Biochemical Society Transactions 34, no. 2 (March 20, 2006): 296–300. http://dx.doi.org/10.1042/bst0340296.

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Strategies for the chemoenzymatic transformation of a racemate into a single stereoisomeric product in quantitative yield have been developed. A range of industrially relevant α-hydroxycarboxylic acids was deracemized in a stepwise fashion via lipase-catalysed enantioselective O-acylation, followed by mandelate racemase-catalysed racemization of the remaining non-reacted substrate enantiomer. Alternatively, aliphatic α-hydroxycarboxylic acids were enzymatically isomerized using whole resting cells of Lactobacillus spp. Enantioselective hydrolysis of rac-sec-alkyl sulphate esters was accomplished using novel alkyl sulphatases of microbial origin. The stereochemical path of catalysis could be controlled by choice of the biocatalyst. Whereas Rhodococcus ruber DSM 44541 and Sulfolobus acidocaldarius DSM 639 act through inversion of configuration, stereo-complementary retaining sulphatase activity was detected in the marine planctomycete Rhodopirellula baltica DSM 10527.

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42

Pogorevc, Mateja, and Kurt Faber. "Purification and Characterization of an Inverting Stereo- and Enantioselective sec-Alkylsulfatase from the Gram-Positive Bacterium Rhodococcus ruber DSM 44541." Applied and Environmental Microbiology 69, no. 5 (May 2003): 2810–15. http://dx.doi.org/10.1128/aem.69.5.2810-2815.2003.

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ABSTRACT Whole cells of Rhodococcus ruber DSM 44541 were found to hydrolyze (±)-2-octyl sulfate in a stereo- and enantiospecific fashion. When growing on a complex medium, the cells produced two sec-alkylsulfatases and (at least) one prim-alkylsulfatase in the absence of an inducer, such as a sec-alkyl sulfate or a sec-alcohol. From the crude cell-free lysate, two proteins responsible for sulfate ester hydrolysis (designated RS1 and RS2) were separated from each other based on their different hydrophobicities and were subjected to further chromatographic purification. In contrast to sulfatase RS1, enzyme RS2 proved to be reasonably stable and thus could be purified to homogeneity. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed a single band at a molecular mass of 43 kDa. Maximal enzyme activity was observed at 30°C and at pH 7.5. Sulfatase RS2 showed a clear preference for the hydrolysis of linear secondary alkyl sulfates, such as 2-, 3-, or 4-octyl sulfate, with remarkable enantioselectivity (an enantiomeric ratio of up to 21 [23]). Enzymatic hydrolysis of (R)-2-octyl sulfate furnished (S)-2-octanol without racemization, which revealed that the enzymatic hydrolysis proceeded through inversion of the configuration at the stereogenic carbon atom. Screening of a broad palette of potential substrates showed that the enzyme exhibited limited substrate tolerance; while simple linear sec-alkyl sulfates (C7 to C10) were freely accepted, no activity was found with branched and mixed aryl-alkyl sec-sulfates. Due to the fact that prim-sulfates were not accepted, the enzyme was classified as sec-alkylsulfatase (EC 3.1.6.X).

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43

Serreqi, Alessio N., and Romas J. Kazlauskas. "Kinetic resolution of sulfoxides with pendant acetoxy groups using cholesterol esterase: substrate mapping and an empirical rule for chiral phenols." Canadian Journal of Chemistry 73, no. 8 (August 1, 1995): 1357–67. http://dx.doi.org/10.1139/v95-167.

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Sulfoxides are valuable chiral auxiliaries because they direct the formation of carbon–carbon bonds. As a route to enantiomerically pure sulfoxides, we examined hydrolase-catalyzed kinetic resolution by hydrolysis of a pendant acetoxy group. Screening hydrolases for the enantioselective hydrolysis of the acetate in 2-(methylsulfinyl)phenyl acetate, 1b, identified cholesterol esterase (CE) as the most enantioselective enzyme. The enantiomeric ratio, E, ranged from 10 to 25, favoring the (R) configuration at sulfur. Competing chemical hydrolysis of 1b caused the large range in the measured values of E. A small-scale (250 mg) resolution of (±)-1b yielded (S)-1b with >99% ee (11% yield) after recrystallization. Changing the methyl substituent to phenyl or n-butyl did not significantly change the enantioselectivity (E = 10 and 15, respectively), but changing it to a chloromethyl substituent lowered the enantioselectivity slightly (E = 5). Changing the phenyl acetate to a naphthyl acetate (2-(phenylsulfinyl)phenyl acetate vs. 1-(phenylsulfinyl)-2-naphthyl acetate) increased the enantioselectivity from 10 to 19. In all cases CE favored the (R)-sulfoxide. To aid the design of new resolutions with CE, we propose an empirical rule that accounts for the observed enantiopreference of CE toward these 5 sulfoxides and 15 other chiral aryl acetates. This empirical rule uses both the size of the substituents and their conformational preferences to predict which enantiomer reacts faster. Keywords: kinetic resolution, lipase, cholesterol esterase, sulfoxides, empirical rule.

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44

Matsumoto, Kazutsugu, Masaki Nogawa, Megumi Shimojo, Hiromichi Ohta, and Minoru Hatanaka. "Enantioselective Microbial Hydrolysis of Disubstituted Cyclic Carbonates." HETEROCYCLES 68, no. 7 (2006): 1329. http://dx.doi.org/10.3987/com-06-10765.

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45

Chĕnevert, Robert, Roxane Pouliot, and Patrick Bureau. "Enantioselective hydrolysis of (±)-chloramphenicol palmitate by hydrolases." Bioorganic & Medicinal Chemistry Letters 4, no. 24 (December 1994): 2941–44. http://dx.doi.org/10.1016/s0960-894x(01)80844-1.

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46

Olejniczak, Teresa, and Zbigniew Ciunik. "Enantioselective hydrolysis of δ-acetoxy-γ-lactones." Tetrahedron: Asymmetry 15, no. 23 (November 2004): 3743–49. http://dx.doi.org/10.1016/j.tetasy.2004.10.023.

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47

Bredikhina, Z. A., V. G. Novikova, and A. A. Bredikhin. "Jacobsen Enantioselective Hydrolysis of Glycidyl Diethyl Phosphate." Russian Journal of General Chemistry 75, no. 10 (October 2005): 1514–16. http://dx.doi.org/10.1007/s11176-005-0460-2.

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48

Sellergren, Börje, and Kenneth J. Shea. "Enantioselective ester hydrolysis catalyzed by imprinted polymers." Tetrahedron: Asymmetry 5, no. 8 (August 1994): 1403–6. http://dx.doi.org/10.1016/0957-4166(94)80096-0.

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49

Matsumoto, K., M. Okudomi, K. Ageishi, T. Yamada, N. Chihara, T. Nakagawa, and K. Mizuochi. "Enantioselective Hydrolysis of Soluble Polymer-Supported Carboxylates." Synfacts 2010, no. 12 (November 22, 2010): 1443. http://dx.doi.org/10.1055/s-0030-1258913.

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50

Smeets, J. W. H., and A. P. G. Kieboom. "Enzymatic enantioselective ester hydrolysis by carboxylesterase NP." Recueil des Travaux Chimiques des Pays-Bas 111, no. 11 (September 2, 2010): 490–95. http://dx.doi.org/10.1002/recl.19921111104.

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Journal articles on the topic 'Enantioselective hydrolyses'

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