89-00-9Relevant academic research and scientific papers
The pyridine ring of NAD is formed by a nonenzymatic pericyclic reaction
Colabroy, Keri L.,Begley, Tadhg P.
, p. 840 - 841 (2005)
The biosynthesis of quinolinate 3, the precursor to the pyridine ring of NAD, is still poorly understood. Two pathways have been identified, one involving the direct formation of quinolinic acid from aspartate and dihydroxyacetone phosphate, the other requiring a five-step degradation of tryptophan. The final step in this degradation is catalyzed by the non-heme Fe(II)-dependent enzyme 3-hydroxyanthranilate-3,4-dioxygenase (HAD). This enzyme catalyzes the oxidative ring opening of 3-hydroxyanthranilate (1) to 2-amino-3-carboxymuconic semialdehyde (ACMS, 2) which then cyclizes to quinolinate (3). In this communication, we demonstrate the following: (1) cyclization of ACMS to 3 is not HAD catalyzed, (2) the most stable form of ACMS in solution is an all trans isomer which undergoes facile cis to trans isomerization about the C2-C3 and C4-C5 double bonds via transient formation of its enol tautomer (6), (3) a model study on the ring opening of N,N-dimethylcarbamoylpyridinium with hydroxide and methoxide suggests that the cyclization of ACMS occurs by an electrocyclization reaction of its enol tautomer 6. Thus, the biosynthesis of quinolinic acid, by the tryptophan pathway, is likely to be a member of a growing family of natural products whose biosynthesis involves a pericyclic reaction. Copyright
Preparation method of nitrogen-containing aromatic dicarboxylic acid
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Paragraph 0022-0084; 0113-0124, (2020/03/02)
The invention discloses a preparation method of nitrogen-containing aromatic dicarboxylic acid. The method includes: taking quinoline, isoquinoline, benzimidazole or benzotriazole and a derivative thereof as the raw materials, adopting oxone as the oxidant, employing a metal salt as the catalyst and using inorganic acid as the medium, adding a phase transfer reagent, and carrying out reaction to obtain nitrogen-containing aromatic dicarboxylic acid. The reagents used by the method are high in stability, convenient for transportation and storage, the operation is simple, the conditions are easily controllable, and the price is low, at the same time, the catalytic effect is good, the yield is high, and waste liquid treatment is easy, therefore the method is convenient for industrial large-scale production.
Observing 3-hydroxyanthranilate-3,4-dioxygenase in action through a crystalline lens
Wang, Yifan,Liu, Kathy Fange,Yang, Yu,Davis, Ian,Liu, Aimin
, p. 19720 - 19730 (2020/09/18)
The synthesis of quinolinic acid from tryptophan is a critical step in the de novo biosynthesis of nicotinamide adenine dinucleotide (NAD+) in mammals. Herein, the nonheme iron-based 3-hydroxyanthranilate-3,4-dioxygenase responsible for quinolinic acid production was studied by performing time-resolved in crystallo reactions monitored by UV-vis microspectroscopy, electron paramagnetic resonance (EPR) spectroscopy, and X-ray crystallography. Seven catalytic intermediates were kinetically and structurally resolved in the crystalline state, and each accompanies protein conformational changes at the active site. Among them, a monooxygenated, seven-membered lactone intermediate as a monodentate ligand of the iron center at 1.59-? resolution was captured, which presumably corresponds to a substrate-based radical species observed by EPR using a slurry of small-sized single crystals. Other structural snapshots determined at around 2.0-? resolution include monodentate and subsequently bidentate coordinated substrate, superoxo, alkylperoxo, and two metal-bound enol tautomers of the unstable dioxygenase product. These results reveal a detailed stepwise O-atom transfer dioxygenase mechanism along with potential isomerization activity that fine-tunes product profiling and affects the production of quinolinic acid at a junction of the metabolic pathway.
Method for preparing nitrogen-containing six-membered ring dicarboxylic acid
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Paragraph 0033-0035; 0037, (2020/04/22)
The invention relates to compound preparation, particularly to a method for preparing nitrogen-containing six-membered ring dicarboxylic acid from a benzo nitrogen-containing six-membered ring compound. According to the method, a raw material compound and a sodium chlorate aqueous solution are catalyzed under an acidic condition to obtain nitrogen-containing six-membered ring dicarboxylic acid, wherein the raw material is a nitrogen-containing six-membered heterocyclic benzocyclic compound. According to the invention, the catalyst of the reaction system is low in toxicity and low in cost, no new impurity is generated in the post-treatment step, and large-scale production is facilitated.
A 2, 3 - pyridine dicarboxylic acid synthesis method
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Paragraph 0009; 0010; 0011; 0012; 0013-0030, (2019/01/08)
The invention discloses a 2, 3 - pyridine dicarboxylic acid synthesis method, CuSO4 · 5 H2 O, sulfuric acid, benzo pyridine sodium chlorate, to aldehyde benzoic acid methyl ester, pyrrole, H2 TCPP - OMe, MnCl2 · 6 H2 O as the main raw material, the synthesis process of the present invention benzo pyridine first NaClO in oxidation system3 - H2 SO4 - CuSO4 The catalyst under Mn - TCPP oxidation under the action of the open loop, after alkali hydrolysis, acidifying the resulting 2, 3 - pyridine dicarboxylic acid. For Mn - TCPP catalyst benzene ring and the double bond is connected to the electron-donative group, double bond can be increased on the electron cloud density, more easily reactant intermediate attack activation, therefore open-loop oxidation effect can be improved, so that the yield is obviously higher than the traditional potassium permanganate oxidation product yield.
Dual Activity of Quinolinate Synthase: Triose Phosphate Isomerase and Dehydration Activities Play Together to Form Quinolinate
Reichmann, Debora,Couté, Yohann,Ollagnier De Choudens, Sandrine
, p. 6443 - 6446 (2015/11/09)
Quinolinate synthase (NadA) is an Fe4S4 cluster-containing dehydrating enzyme involved in the synthesis of quinolinic acid (QA), the universal precursor of the essential coenzyme nicotinamide adenine dinucleotide. The reaction catalyzed by NadA is not well understood, and two mechanisms have been proposed in the literature that differ in the nature of the molecule (DHAP or G-3P) that condenses with iminoaspartate (IA) to form QA. In this article, using biochemical approaches, we demonstrate that DHAP is the triose that condenses with IA to form QA. The capacity of NadA to use G-3P is due to its previously unknown triose phosphate isomerase activity.
OZONOLYSIS OF AROMATICS AND/OR OLEFINS
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Page/Page column 13-14, (2010/04/03)
The invention pertains to a process for oxidizing unsaturated starting materials, comprising: (i) providing a liquid composition containing an olefin and/or aromatic starting compound, (ii) compressing an ozone-containing gas to a pressure of at least 5 bar absolute, (iii) introducing the compressed ozone-containing gas in one or more microreactors, bringing said gas into contact with said liquid composition (i), to obtain an ozonide, (iv) and optionally subjecting said ozonide to oxidative or reductive degradation. The use of compressed ozone makes it possible to mix large gas volumes with small liquid volumes, and achieve satisfactory contact between the gas and liquid reactants. This dramatically improves yields over conventional micro-reactor-driven ozonolysis.
PROCESS FOR THE SAFE OZONOLYSIS OF ORGANIC COMPOUNDS IN FLAMMABLE SOLVENTS
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Page/Page column 22-23, (2008/12/06)
An improved process for the safe ozonolysis of unsaturated, organic carbon compounds having one or more olefinic or aromatic double bonds in the molecule in flammable solvents for the preparation of mono- or biscarbonyl or hydroxy compounds, in which ozonolysis is carried out with the use of an ozone-carrying inert gas/O2 stream, in which the oxygen concentration in the inert gas/O2 stream is above the known limiting oxygen concentration of the homogeneous fuel/gas mixtures and below the safety-critical limiting oxygen concentration of the heterogeneous mixture of the liquid fuel and oxygen-containing gas which is dependent on the reaction conditions and at which ignition and flame propagation no longer take place.
Process for producing high-purity 2,3-pyridinedicarboxylic acid
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Page/Page column 4; 5, (2008/06/13)
A process for producing 2,3-pyridinedicarboxylic acid having a significantly decreased heavy metal content and capable of satisfying the purity level required for medicinal and agricultural chemicals comprising the steps of: adding at least one sulfur-containing substance selected from a hydrosulfide, a sulfide, a polysulfide, and sulfur to an aqueous solution of 2,3-pyridinedicarboxylic acid or its salt; removing the resulting precipitates from the solution; acidifying the solution with a mineral acid to precipitate 2,3-pyridinedicarboxylic acid; and recovering the precipitates. The aqueous solution to be treated may be an aqueous solution of an alkali metal salt of 2,3-pyridinedicarboxylic acid obtained by alkali decomposition of 2,3-pyridinedicarboxylic acid copper (II) salt, which has been formed or precipitated in a process for producing 2,3-pyridinedicarboxylic acid.
Process for producing 2,3-pyridinedicarboxylic acid
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Page/Page column 8-9, (2008/06/13)
Highly pure 2,3-pyridinedicarboxylic acid is produced by a process suitable for application in commercial production with a high yield and with recirculation of waste liquor. The process comprises the steps of: (a) oxidizing quinoline or 8-hydroxyquinoline in a solvent in the presence of copper (II) ions to precipitate copper (II) salt of 2,3-pyridinedicarboxylic acid and then separate the precipitates, (b) reacting the separated copper (II) salt with an alkali in a solvent to obtain a solution of an alkali metal salt of 2,3-pyridinedicarboxylic acid, and (c) reacting the solution of the alkali metal salt with a mineral acid to precipitate 2,3-pyridinedicarboxylic acid and then separate the precipitates, and is characterized in that (A) part or all of the solution obtained after the precipitated 2,3-pyridinedicarboxylic acid is separated in step (c) is used as at least part of the solvent in step (a) or (b), or (B) copper or a copper compound is added to the solution obtained after the precipitated 2,3-pyridine-dicarboxylic acid is separated in step (c) to recover the 2,3-pyridinedicarboxylic acid remaining in the solution as its copper (II) salt.
