1072-84-0Relevant articles and documents
Heteroaryl hydroxycarbonylation: An efficient, robust, practically scalable approach using formyl acetate as the co source
Gadakh, Amol V.,Chikanna, Dinesh,Rindhe, Sahebrao S.,Karale, Bhausaheb K.
, p. 658 - 666 (2012)
A simple, efficient, regioselective, and scalable palladium-catalyzed hydroxycarbonylation of heteroaryl halides to corresponding carboxylic acids using acetic-formic anhydride in presence of Pd(OAc)2, dppf, and diisopropylethyl amine in dimethyl formamide at 80-90 °C in excellent yields. Taylor & Francis Group, LLC.
Oxidation of imidazole- and pyrazole-derived aldehydes by plant aldehyde dehydrogenases from the family 2 and 10
Fr?mmel, Jan,Kon?itíková, Radka,Kope?ny, David,Soural, Miroslav,?ebela, Marek
, p. 194 - 201 (2019)
Plant cytosolic aldehyde dehydrogenases from family 2 (ALDH2s, EC 1.2.1.3) are non-specific enzymes and participate for example in the metabolism of acetaldehyde or biosynthesis of phenylpropanoids. Plant aminoaldehyde dehydrogenases (AMADHs, ALDH10 family, EC 1.2.1.19) are broadly specific and play an important role in polyamine degradation or production of osmoprotectants. We have tested imidazole and pyrazole carbaldehydes and their alkyl-, allyl-, benzyl-, phenyl-, pyrimidinyl- or thienyl-derivatives as possible substrates of plant ALDH2 and ALDH10 enzymes. Imidazole represents a building block of histidine, histamine as well as certain alkaloids. It also appears in synthetic pharmaceuticals such as imidazole antifungals. Biological compounds containing pyrazole are rare (e.g. pyrazole-1-alanine and pyrazofurin antibiotics) but the ring is often found as a constituent of many synthetic drugs and pesticides. The aim was to evaluate whether aldehyde compounds based on azole heterocycles are oxidized by the enzymes, which would further support their expected role as detoxifying aldehyde scavengers. The analyzed imidazole and pyrazole carbaldehydes were only slowly converted by ALDH10s but well oxidized by cytosolic maize ALDH2 isoforms (particularly by ALDH2C1). In the latter case, the respective Km values were in the range of 10–2000 μmol l?1; the kcat values appeared mostly between 0.1 and 1.0 s?1. The carbaldehyde group at the position 4 of imidazole was oxidized faster than that at the position 2. Such a difference was not observed for pyrazole carbaldehydes. Aldehydes with an aromatic substituent on their heterocyclic ring were oxidized faster than those with an aliphatic substituent. The most efficient of the tested substrates were comparable to benzaldehyde and p-anisaldehyde known as the best aromatic aldehyde substrates of plant cytosolic ALDH2s in vitro.
Synthesis method of 1H-imidazole-4-carboxylic acid
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Paragraph 0022; 0029; 0036; 0043; 0050, (2018/05/16)
The invention discloses a synthesis method of 1H-imidazole-4-carboxylic acid. The method comprises steps as follows: (1) a hydrochloric acid solution is added to a reaction kettle, chromium trioxide is added under the stirring condition, the mixture is stirred uniformly and heated to 40-50 DEG C, pyridine is dropwise added, the mixture is stirred to react for 2-3 h after pyridine is dropwise added, PCC (pyridinium chlorochromate) is prepared, TiO2 is added, a dichloromethane solution of 4-methylimidazole is dropwise added under the stirring condition, the mixture is subjected to a reaction at40-50 DEG C for 3-4 h, then, filtration and centrifugation are performed, an organic layer is collected, reduced pressure distillation is performed, and 1H-imidazole-4-formaldehyde is prepared; (2) prepared 1H-imidazole-4-formaldehyde and dichloromethane are mixed, the obtained mixture is heated to 40-50 DEG C, KMnO4 is added, the mixture is mixed uniformly and stirred for a reaction for 3-4 h, filtration, reduced pressure distillation and recrystallization are performed, and 1H-imidazole-4-carboxylic acid is prepared. The synthesis method is simple to operate and mild in condition, fewer by-products are produced, the product purity is high and the product yield is higher.
Preparation method of 1H-imidazole-4-carboxylic acid
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Paragraph 0018-0029, (2017/06/02)
The invention discloses a preparation method of 1H-imidazole-4-carboxylic acid. The preparation method includes dissolving 4-methylimidazole into an organic solvent, adding an oxidizing agent and a catalyst with stirring evenly, heating to 70-90 DEG C at a normal pressure, feeding oxygen, conducting refluxing reaction for 90-120 minutes and purifying to obtain the 1H-imidazole-4-carboxylic acid. The preparation method has the advantages that the preparation method is capable of preparing the 1H-imidazole-4-carboxylic acid through a one-step method, and is mild in reaction condition, high in conversion rate and simple in aftertreatment operation by the aid of a novel catalyst system, thereby having a promising industrial prospect.
