- Regioselective preparation of (R)-2-(4-hydroxyphenoxy)propionic acid with a fungal peroxygenase
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The extracellular heme-thiolate peroxygenase of Agrocybe aegerita catalyzed the H2O2-dependent hydroxylation of 2-phenoxypropionic acid (POPA) to give the herbicide precursor 2-(4-hydroxyphenoxy)propionic acid (HPOPA). The reaction proceeded regioselectively with an isomeric purity near 98%, and yielded the desired R-isomer of HPOPA with an enantiomeric excess of 60%. 18O-labeling experiments showed that the phenolic hydroxyl in HPOPA originated from H2O2, which establishes that the reaction is mechanistically a peroxygenation. Our results raise the possibility that fungal peroxygenases may be useful for a variety of organic oxidations.
- Kinne, Matthias,Ullrich, René,Hammel, Kenneth E.,Scheibner, Katrin,Hofrichter, Martin
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Read Online
- Method for synthesizing herbicide clodinafop-propargyl key intermediate
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The invention discloses a method for synthesizing a herbicide clodinafop-propargyl key intermediate. According to the method, methyl 2-chloropropionate and hydroquinone are used as starting raw materials, under the catalytic action of inorganic alkali, nucleophilic substitution reaction is conducted, and methyl (R,S)-2-(4-hydroxyphenoxy)propionate is obtained; the generated methyl (R,S)-2-(4-hydroxyphenoxy)propionate is subjected to resolution hydrolysis reaction under the action of aspergillus oryzae WZ007, and a methyl (R)-(+)-2-(4-hydroxyphenoxy)propionate product is obtained; the generatedproduct is subjected to hydrolysis reaction continuously to obtain a target product R(+)-2-(4-hydroxyphenoxy)propionic acid. The synthesis method is simple; in the synthesis process, thalli of the aspergillus oryzae WZ007 are used for catalyzing selective hydrolysis of a methyl (R,S)-2-(4-hydroxyphenoxy)propionate substrate, thus the R-configuration ester and the S-configuration acid are obtained, the purpose of resolution is achieved, moreover, the raw materials of the method are cheap, the production cost is low, and the economic performance is good, so that the method has good applicationprospects.
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Paragraph 0047
(2018/11/27)
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- Preparation method of (R)-(+)-2-p-hydroxyl phenoxyl propionic acid
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The invention relates to a preparation method of (R)-(+)-2-p-hydroxyl phenoxyl propionic acid. The method comprises the following steps of taking (S)-(-)-lactic acid as a raw material, and performingthree-step reaction, i.e., esterification, nucleophilic substitution and hydrolysis to obtain a target compound. A synthetic process for the (R)-(+)-2-p-hydroxyl phenoxyl propionic acid is further optimized, and the optimum reaction condition and reagent are screened. According to the preparation method designed in the invention, the reaction steps are shortened, and the yield and optical purity of the (R)-(+)-2-p-hydroxyl phenoxyl propionic acid are improved.
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Paragraph 0045; 0048
(2018/11/22)
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- Preparation method of D-HPPA
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The invention provides a novel preparation method of D-HPPA by using a novel catalyst. The method is simple and applicable to industrialization.
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Paragraph 0035; 0036; 0037; 0038; 0039; 0040; 0041
(2017/05/13)
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- Resolution of (R, S)-ethyl-2-(4-hydroxyphenoxy) propanoate using lyophilized mycelium of Aspergillus oryzae WZ007
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The mycelium of Aspergillus oryzae WZ007 was successfully developed to kinetic resolution of (R, S)-ethyl-2-(4-hydroxyphenoxy) propanoate ((R, S)-EHPP) for production of (R)-ethyl-2-(4-hydroxyphenoxy) propanoate ((R)-EHPP). The key biocatalytic process parameters (pH, temperature, rotation speed and substrate concentration) were optimized. Under the optimum conditions, the optical purity of (R)-EHPP was improved up to >99% when the conversion was above 49%. A. oryzae WZ007 whole-cell lipase exhibited high reaction capacity, enantioselectivity and good reusability. The tolerable substrate concentration was 0.5 mol/L, and dry mycelium of A. oryzae WZ007 maintains over 80% of its initial activity after eight repeating cycles. Therefore the enzymatic preparation of (R)-EHPP route was suitable for industrial application.
- Zheng, Jian-Yong,Wu, Jia-Yu,Zhang, Yin-Jun,Wang, Zhao
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- Synthesis of dendrimer-type chiral stationary phases based on the selector of (1S,2R)-(+)-2-amino-1,2-diphenylethanol derivate and their enantioseparation evaluation by HPLC
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In our recent work, a series of dendritic chiral stationary phases (CSPs) were synthesized, in which the chiral selector was L-2-(p-toluenesulfonamido)-3- phenylpropionyl chloride (selector I), and the CSP derived from three-generation dendrimer showed the best separation ability. To further investigate the influence of the structures of dendrimer and chiral selector on enantioseparation ability, in this work, another series CSPs (CSPs 1-4) were prepared by immobilizing (1S,2R)-1,2-diphenyl-2-(3-phenylureido)ethyl 4-isocyanatophenylcarbamate (selector II) on one- to four-generation dendrimers that were prepared in previous work. CSPs 1 and 4 demonstrated the equivalent enantioseparation ability. CSPs 2 and 3 showed the best and poorest enantioseparation ability respectively. Basically, these two series of CSPs exhibited the equivalent enantioseparation ability although the chiral selectors were different. Considering the enantioseparation ability of the CSP derived from aminated silica gel and selector II is much better than that of the one derived from aminated silica gel and selector I, it is believed that the dendrimer conformation essentially impacts enantioseparation.
- He, Bao-Jiang,Yin, Chuan-Qi,Li, Shi-Rong,Bai, Zheng-Wu
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experimental part
p. 69 - 76
(2010/09/09)
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- Process for the preparation of substituted tetralin and substituted indane derivatives
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The present invention relates to novel processes for the preparation of substituted tetralin. and substituted indane derivatives. The present invention is further directed to novel processes for the preparation of intermediates in the preparation of the substituted tetralin and substituted indane derivatives.
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Page/Page column 30
(2008/06/13)
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- Microbial deracemization of α-substituted carboxylic acids: Substrate specificity and mechanistic investigation
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A new enzymatic method for the preparation of optically active α-substituted carboxylic acids is reported. This technique is called deracemization reaction, which provides us with a route to obtain the enantiomerically pure compounds, theoretically in 100% yield starting from the racemic mixture. This means that the synthesis of a racemate is almost equal to the synthesis of the optically active compound, and this concept is entirely different from the commonly accepted one in the asymmetric synthesis. Using the growing cell system of Nocardia diaphanozonaria JCM3208, racemates of 2-aryl- and 2-aryloxypropanoic acid are deracemized smoothly and (R)-form-enriched products are recovered in high chemical yield (>50%). In addition, using optically active starting compounds and deuterated derivatives as well as inhibitors, we have disclosed the fact that a new type of enzyme takes part in this biotransformation, and that the reaction proceeds probably via the same mechanism as that in rat liver.
- Kato, Dai-Ichiro,Mitsuda, Satoshi,Ohta, Hiromichi
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p. 7234 - 7242
(2007/10/03)
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- Design, synthesis, and evaluation of postulated transient intermediate and substrate analogues as inhibitors of 4-hydroxyphenylpyruvate dioxygenase
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An epoxybenzoquinone, 4-hydroxyphenoxypropionic acid, and 2-hydroxy-3-phenyl-3-butenoic acid derivatives have been designed, synthesized, and evaluated for in vitro inhibition activity against 4-hydroxyphenylpyruvate dioxygenase (4-HPPD) from pig liver by the spectrophotometric enol-borate method. The biological data demonstrated that neither epoxybenzoquinone ester nor 2-hydroxy-3-phenyl-3-butenoic acid is an inhibitor of 4-HPPD. The most potent 4-HPPD inhibitor tested was 3-hydroxy-4-phenyl-2(5H)-furanone with an IC50 value of 0.5 μM, which may serve as a lead compound for further design of more potent 4-HPPD inhibitors.
- Lin, Yun-Loung,Huang, Jian-Lin,Wu, Chung-Shieh,Liu, Hung-Ge,Yang, Ding-Yah
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p. 1709 - 1713
(2007/10/03)
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- (2-quinoxalinyloxy) phenoxypropanoic acids and related derivatives as anticancer agents
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This invention relates to (2-quinoxalinyloxy)phenoxypropanoic acids, related derivatives thereof, enantiomeric and diastereomeric forms thereof, mixtures of enantiomeric diastereomeric forms thereof, and pharmaceutically acceptable salt forms thereof, pharmaceutical compositions containing them, processes for their preparation, and methods of using them to treat cancer, particularly solid tumors, in mammals.
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- Preparation of optically active α-(hydroxyphenoxy)alkanecarboxylic acids and derivatives thereof
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Optically active α-(hydroxyphenoxy)-alkanecarboxylic acids or derivatives thereof, for example D-2-(4-hydroxyphenoxy)propionic acid or lower alkyl ester thereof, are prepared by (a) saponifying an alkyl ester of an optically active α-halogeno-alkanecarboxylic acid, in an alcoholic solvent medium, by reacting same with an aqueous solution of an alkali metal hydroxide, thereby providing a solution of an alkali metal salt of an optically active α-halogeno-alkanecarboxylic acid, (b) next reacting the step (a) solution thus provided with a dihydroxybenzene or salt thereof, in the presence of an alkali metal hydroxide and in an alcoholic solvent medium, and thence (c) recovering the optically active α-(hydroxyphenoxy)-alkanecarboxylic acid or derivative thereof from the medium of reaction.
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- Synthesis of 2-(4-hydroxyphenoxy)alkanoic acids
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A method for synthesizing 2-(4-hydroxyphenoxy)alkanoic acids by reacting a hydroxyaromatic ketone derivative with a 2-substituted alkanoic acid under basic conditions and thereafter oxidizing the intermediate with subsequent hydrolysis.
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- Process for the preparation of optically active 2-(4-methoxyphenoxy) propionic acid
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A process for the preparation of optically active 2-(4-methoxyphenoxy)propionic acid of at least 75 percent enantiomeric excess of the desired optical isomer comprised of contacting 2-chloropropionic acid or a lower alkyl ester or an alkali metal salt thereof, having an optical purity greater than 85 percent of the opposite configuration, with from 3 to 10 molar equivalents of 4-methoxyphenol in an aqueous base.
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- Process for racemizing optically active alpha-phenoxypropionic acid and derivatives thereof
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Optically active enantiomers of alkyl α-phenoxypropionates, and of derivatives thereof, can be racemized in good yields and without formation of decomposition products with the aid of an alkali metal (C1 -C5) alcoholate, an alkali metal hydroquinone, an alkali metal phenolate or an alkali metal hydroxyphenoxypropionate, or derivatives thereof.
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- Derivatives of (pyrimidyloxy)phenoxy-alkanecarboxylic acid and herbicidal compositions thereof
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A compound of general formula I: STR1 wherein A, B, D, E, and V are independently chosen from hydrogen, halogen, nitro, cyano, thiocyano, amino, alkyl, alkoxy, alkylthio, alkenyl, cycloalkyl, carbalkoxy, phenyl, phenoxy or phenylthio; R1 and R2 are independently hydrogen, alkyl, alkenyl, alkanoyl, or R1 and R2 together are alkylidene; W is carboxy or a functional derivative thereof or CH2 Z wherein Z is halogen, hydroxy, alkoxy, alkylthio, formyl or amino; and X and Y are oxygen or sulfur.
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