- Integration of chemical and biological catalysis: Production of furylglycolic acid from glucose via cortalcerone
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Furylglycolic acid (FA), a pseudoaromatic hydroxy-acid suitable for copolymerization with lactic acid, can be produced from glucose via enzymatically derived cortalcerone using a combination of Bronsted and Lewis acid catalysts. Cortalcerone is first converted to furylglyoxal hydrate (FH) over a Bronsted acid site (HCl or Al-containing beta-zeolite), and FH is subsequently converted to FA over a Lewis acid site (Sn-beta zeolite). Selectivity for conversion of FH to FA is as high as 80% at 12% conversion using tetrahydrofuran (THF) as a solvent at 358 K. Higher conversion of FH leads to FA-catalyzed degradation of FH and subsequent deactivation of the catalyst by the deposition of carbonaceous residues. The deactivated catalyst can be regenerated by calcination. Cortalcerone can be produced from 10% glucose solution using recombinant Escherichia coli strains expressing pyranose 2-oxidase and aldos-2-ulose dehydratase from the wood-decay fungus Phanerochaete chrysosporium BKM-F-1767. This enzymatically derived cortalcerone is converted in one pot to FA in a methanol/water solvent over an Al-containing Sn-beta zeolite possessing both Bronsted and Lewis acid sites, achieving 42% selectivity to FA at 53% cortalcerone conversion.
- Schwartz, Thomas J.,Goodman, Samuel M.,Osmundsen, Christian M.,Taarning, Esben,Mozuch, Michael D.,Gaskell, Jill,Cullen, Daniel,Kersten, Philip J.,Dumesic, James A.
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- Synthesis of α-hydroxycarboxylic acids from various aldehydes and ketones by direct electrocarboxylation: A facile, efficient and atom economy protocol
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In present work, the formation of α-hydroxycarboxylic acids have been described from various aromatic aldehydes and ketones via direct electrocarboxylation method with 80-92% of yield without any side product and can be purified by simple recrystallization using sacrificial Mg anode and Pt cathode in an undivided cell, CO2at (1 atm) was continuously bubbled in the cell throughout the reaction using tetrapropylammonium chloride as a supporting electrolyte in acetonitrile. The synthesized compounds obtained in fair to excellent yield with a high level of purity. The characterization of electrocarboxylated compounds was done with spectroscopic techniques like IR, NMR (1H & 13C), mass and elemental analysis.
- Singh, Kishanpal,Sohal, Harvinder Singh,Singh, Baljit
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p. 839 - 845
(2021/04/09)
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- The Synthesis of Chiral α-Aryl α-Hydroxy Carboxylic Acids via RuPHOX-Ru Catalyzed Asymmetric Hydrogenation
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A ruthenocenyl phosphino-oxazoline-ruthenium complex (RuPHOX?Ru) catalyzed asymmetric hydrogenation of α-aryl keto acids has been successfully developed, affording the corresponding chiral α-aryl α-hydroxy carboxylic acids in high yields and with up to 97% ee. The reaction could be performed on a gram scale with a relatively low catalyst loading (up to 5000 S/C) and the resulting products can be transformed to several chiral building blocks, biologically active compounds and chiral drugs. (Figure presented.).
- Guo, Huan,Li, Jing,Liu, Delong,Zhang, Wanbin
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p. 3665 - 3673
(2017/09/11)
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- Preparation method of 2-carbonylfuran compounds
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The invention relates to the field of synthesis of carbonylfuran compounds and discloses a preparation method of the 2-carbonylfuran compounds adopting a structure shown in a formula (I). The method comprises the following steps: (1) a furan compound adopting a structure shown in a formula (II) and an aldehyde compound with the general formula of R1CHO have a condensation reaction in presence of an acid catalyst; (2) a condensation product in the step (1) and an oxidizing agent have an oxidation reaction under conditions of the oxidation reaction. Compared with the traditional method taking furan as the raw material and adopting acetylation and sodium nitrite oxidation technologies, the preparation method of the 2-carbonylfuran compounds has the advantages that few salts are contained in wastewater, the treatment is easy, the reaction technologies are clean and environment-friendly, and the yield is higher.
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Paragraph 0051; 0052
(2016/10/17)
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- Carboxylation with CO2 via brook rearrangement: Preparation of α-hydroxy acid derivatives
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In the presence of CsF, a wide range of α-substituted α-siloxy silanes were carboxylated under a CO2 atmosphere (1 atm) via Brook rearrangement. A variety of α-substituents including aryl, alkenyl, and alkyl groups were tolerated to afford α-hydroxy acids in moderate-to-high yields. One-pot synthesis from aldehydes using PhMe2SiLi and CO 2 was also possible, providing α-hydroxy acids without the isolation of an α-hydroxy silane.
- Mita, Tsuyoshi,Higuchi, Yuki,Sato, Yoshihiro
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- Methods for treating leukemia and myelodysplastic syndrome, and methods for identifying agents for treating same
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The present disclosure relates to methods for treating leukemia, pre-leukemic conditions, as well as myelodysplastic syndrome and acute myelogenous leukemia. The present disclosure further relates to compounds that can be used for treating leukemia, pre-leukemic conditions, as well as myelodysplastic syndrome and acute myelogenous leukemia. The present disclosure also relates to methods for identifying compounds that can be used for treating leukemia, pre-leukemic conditions, as well as myelodysplastic syndrome.
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- α-Ketocarboxylic acid-based inhibitors of protein tyrosine phosphatases
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A series of aryl α-ketocarboxylic acids was synthesized and investigated as inhibitors for the protein tyrosine phosphatase from Yersinia enterocolitica. IC50 values for these compounds range from 79 to 2700 μM. Larger aromatic groups, and aromatic groups with high electron density, lead to more potent inhibitors. In general, the related aryl α-hydroxycarboxylic acids show lower activity.
- Chen, Yen Ting,Onaran,Doss, Christopher J.,Seto, Christopher T.
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p. 1935 - 1938
(2007/10/03)
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