- Development of a scalable process for a key intermediate of (R)-metalaxyl by enzymatic kinetic resolution
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A scale-up study was carried out for the enzyme-catalyzed kinetic resolution of 2-methoxyethyl N-(2,6)-dimethylphenyl)-alaninate rac-3 for the preparation of (R)-metalaxyl at 20-L scale. Immobilization of lipase PS on a polymeric support enabled the reuse of the enzyme. The unreacted enantiomer was racemized by means of acid/aldehyde catalyzed Schiff base intermediate formation. The combination of lipase PS-catalyzed hydrolytic kinetic resolution and racemization of the remaining ester gave a satisfactory reaction yield (> 80%) and high enantiomeric excess (96% ee) for one recycle.
- Park, Oh-Jin,Lee, Sang-Hyun,Park, Tae-Yoon,Chung, Won-Gyo,Lee, Sang-Who
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Read Online
- New biocatalytic route for the production of enantioenriched β-alanine derivatives starting from 5- and 6-monosubstituted dihydrouracils
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Taking advantage of the catalytic promiscuity of pyrimidine-catabolism enzymes (dihydropyrimidinase (E.C. 3.5.2.2), N-carbamoyl-β-alanine amidohydrolase (E.C. 3.5.1.6)), the production of different β-alanine derivatives starting from 5- and 6-monosubstituted dihydrouracils has been evaluated using a mimesis approach. In this work, the S-enantioselective character of dihydropyrimidinase from Sinorizhobium meliloti toward 6-monosubstituted dihydrouracil derivatives has been shown. An inverted R-/S-enantioselectivity of N-carbamoyl-β-alanine amidohydrolase from Agrobacterium tumefaciens toward two different N-carbamoyl-β-amino acids has been proved. Our results have shown for the first time that this mimetic tandem constitutes an interesting biotechnological tool for the preparation of different β-alanine derivatives in an environmentally friendly way, allowing the production of enantioenriched (R)-α-phenyl-β-alanine (e.e. > 95%) and (R)-α-methyl-β-alanine (e.e. > 90%).
- Martínez-Gómez, Ana Isabel,Clemente-Jiménez, Josefa María,Rodríguez-Vico, Felipe,Kanerva, Liisa T.,Li, Xiang-Guo,Heras-Vázquez, Francisco Javier Las,Martínez-Rodríguez, Sergio
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p. 2090 - 2096
(2013/02/25)
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- HETEROARYL BTK INHIBITORS
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The present invention provides compounds useful as inhibitors of Btk, compositions thereof, and methods of using the same.
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Page/Page column 104
(2011/04/14)
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- Palladium-catalyzed coupling reaction of amino acids (esters) with aryl bromides and chlorides
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The bulky and electron-rich MOP type ligands and Pd(dba)2 combinations showed high efficiency for the coupling reactions of amino acids and inactive aryl halides to give N-aryl amino acids. Under the catalytic conditions, not only α-amino acids, but also β-, γ-, and δ-amino acids have been coupled with aryl chlorides in moderate to high yields; in the case of optically pure β-amino acids as substrates, the optical purities of the coupling products retained.
- Ma, Fangfang,Xie, Xiaomin,Ding, Lina,Gao, Jinsheng,Zhang, Zhaoguo
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experimental part
p. 9405 - 9410
(2011/12/14)
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- NOVEL COMPOUNDS
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This invention relates to novel amide derivatives and salts thereof. More particularly, it relates to novel amide derivatives and salts thereof which act as a ROCK inhibitor, to a pharmaceutical composition comprising the same and to a method of using the same therapeutically in the treatment and/or prevention of ROCK-related disease.
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Page/Page column 28
(2008/06/13)
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- Microbial deracemization of α-substituted carboxylic acids: Control of the reaction path
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A novel approach to preparing optically active α-substituted carboxylic acids using the whole cells of Nocardia diaphanozonaria JCM 3208 is described. When 2-phenylthiopropanoic acid and 2-methyl-3-phenylpropanoic acid were subjected to the reaction under aerobic conditions, the oxidation reaction proceeded preferentially rather than deracemization of these substrates. Herein, we report the design of reaction conditions to increase the deracemization activity in preference to oxidation reactions. In addition, we have successfully detected a metabolic intermediate in the reaction mixture of 2-methyl-3-phenylpropanoic acid, which indicates that the deracemization is a competitive reaction against the α-oxidation pathway of fatty acid metabolism.
- Kato, Dai-Ichiro,Miyamoto, Kenji,Ohta, Hiromichi
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p. 2965 - 2973
(2007/10/03)
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