89-01-0Relevant articles and documents
Method for preparing nitrogen-containing six-membered ring dicarboxylic acid
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Paragraph 0038-0040; 0042, (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 Green One-Pot Synthesis of vic -Amidino (Hetero)aromatic Acids from 1,2-Dinitriles
Tkachuk, Volodymyr A.,Omelchenko, Iryna V.,Hordiyenko, Olga V.
, p. 851 - 857 (2017/04/06)
Phthalonitrile undergoes partial hydration in MeOH-H2O media in the presence of an equimolar amount of NaOH to afford 2-carbamimidoylbenzoic acid in good yield in one step. This and similar vic-amidino (hetero)aromatic acids also could be synthesized from corresponding 1,2-dinitriles by hydrolysis in aqueous MeOH catalyzed by an equimolar amount of NaOH of in situ generated 1,1-dimethoxy-1H-isoindol-3-amine or its counterparts. Protonation of the synthesized amidino acids, esterification, and reamination of the parent amidino benzoic acid with N-nucleophiles were performed.
Nucleophically transformed N-heterocyclic nitriles trapped by cyanooxomolybdates(IV): Crystallographic and spectroscopic study
Ryniewicz, Anna,Tomecka, Monika,Szklarzewicz, Janusz,Matoga, Dariusz,Nitek, Wojciech
, p. 229 - 237,9 (2020/07/31)
The reaction of K3Na[Mo(CN)4O2] ·6H2O with 2,3-dicyanopyrazine or 2-pyridinecarbonitrile in aqueous media results in isolation of two new compounds of formulae (PPh 4)2[Mo(CN)3O(pzac)]·2H2O (Hpzac = 3-carbamoyl-2-pyrazinecarboxylic acid) and (PPh4) 2[Mo(CN)3O(pynccn)]·3H2O·EtOH (Hpynccn = 2-pyridineiminocarbonitrile) respectively. X-ray single crystal structure measurements as well as physicochemical measurements confirm transformations of 2,3-dicyanopyrazine to 3-carbamoyl-2-pyrazinecarboxylic acid and 2-pyridinecarbonitrile to 2-pyridineiminocarbonitrile. All complexes are characterized by elemental analysis, IR and UV-Vis spectroscopy. Metal-assisted ligand transformations are studied spectrophotometrically in the pH range 8.5-11.5. Two different pathways of nitrile reactivity are shown and discussed.
A [2 × 2] nickel(II) grid and a copper(II) square result from differing binding modes of a pyrazine-based diamide ligand
Klingele, Julia,Boas, John F.,Pilbrow, John R.,Moubaraki, Boujemaa,Murray, Keith S.,Berry, Kevin J.,Hunter, Keith A.,Jameson, Geoffrey B.,Boyd, Peter D. W.,Brooker, Sally
, p. 633 - 645 (2008/02/08)
The potentially bis-terdentate diamide ligand N,N′-bis[2-(2-pyridyl) ethyl]pyrazine-2,3-dicarboxamide (H2LEt) was structurally characterised. Potentiometric titrations revealed rather low pKa values for the deprotonation of the first amide group of H2L Et (14.2) and N,N′-bis(2-pyridylmethyl)pyrazine-2,3- dicarboxamide (H2LMe, 13.1). Two tetranuclear copper(ii) square complexes of H2LEt with a paddle-wheel appearance, in which each ligand strand acts as a linear N3-NO hybrid terdentate-bidentate chelate, have been isolated and structurally characterised. Complex [CuII4(H2LEt) 2(HLEt)2](BF4)6· 3MeCN·0.5H2O (3·3MeCN·0.5H2O), with two nondeprotonated zwitterionic ligand strands and two monodeprotonated ligand strands, is formed in the 1: 1 reaction of H2LEt and Cu(BF4)2·4H2O. It has a polymeric chain structure of tetranuclear subunits connected by N-H...N hydrogen bonds. The same reaction carried out with one equivalent of base gives the related compound [CuII4(HLEt)4](BF 4)4 (4), with all four ligand strands monodeprotonated. It consists of isolated tetranuclear units. In both 3·3MeCN·0.5 H2O and 4 the copper(ii) ions are in five-coordinate N4O environments but the degree of trigonality (τ) differs [3· 3MeCN·0.5H2O 0.14 ≤ τ ≤ 0.26; 4 τ = 0.45]. Under the same reaction conditions as for 4 but using Ni(BF4) 2·6H2O a tetranuclear [2 × 2] grid-type complex, [NiII4(HLEt)4](BF 4)·10H2O (5·10H2O), is formed. The structure determination showed that the nickel(ii) ions have N6 distorted octahedral coordination spheres and all four ligand strands are monodeprotonated and act as N3-N3 bis-terdentate chelates. Magnetic susceptibility data show that the complexes 3·4H2O, 4 and 5·10H2O exhibit very weak antiferromagnetic spin coupling. The energies and multiplicities of the spin states of 3·4H 2O and 4 were determined from the temperature dependence of the magnetic susceptibility and indicate that a singlet state is lowest and the quintet state highest. This is consistent with the X-band EPR spectra of polycrystalline powders of 3·4H2O and 4, measured down to 2.3 K, where the resonances observed at the lowest temperature are due to a triplet state. The g-values of the individual ions of 4 are consistent with the expected dx 2 -y 2 ground state for five-coordinate copper(ii) in an approximately square pyramidal configuration. The Royal Society of Chemistry 2007.
Permanganate Oxidation of Quinoxaline and Its Derivatives
Obafemi, Craig A.,Pfleiderer, Wolfgang
, p. 1549 - 1556 (2007/10/02)
The oxidation reaction of a series of quinoxaline derivatives, using KMnO4 in the presence or absence of NaOH, are described.Neutral oxidation of 2-chloro- and 2,3-dichlorodioxalines 2-4 afforded the corresponding chloro- and dichloropyrazinedicarboxilic acids 13 and 14 in good yield.On the other hand, oxidation of quinoxalin-2(1H)-one and 1,4-dihydroquinoxaline-2,3-dione derivatives in alkaline medium gave different products, with the quinoxalin-2(1H)-one (5) forming 1,4-dihydroquinoxaline-2,3-dione (9), while various substituted quinoxalin-2,3-dione derivatives (see 9-11) gave a new type of dimeric products.The structural assignments for the new compounds were based on spectroscopic data.
Aza- and Diazaannulenones. Influence of Nitrogen Position on Their Reactivity and Stability
Gavina, Francisco,Costero, Ana M.,Andreu, M. Rosario,Ayet, M. Dolores
, p. 5417 - 5421 (2007/10/02)
Three new elusive intermediates, 3-aza-2,4-cyclopentadienone, 2,5-diaza-2,4-cyclopentadienone, and 3,4-diaza-2,4-cyclopentadienone, are reported.The three species can act either as dienes or as dienophiles in Diels-Alder reactions.The influence of the number and position of nitrogen atoms on their stability is studied.
1,1-Alkanediol dicarboxylate linked antibacterial agents
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, (2008/06/13)
Useful antibacterial agents in which a penicillin and/or a beta-lactamase inhibitor are linked via 1,1-alkanediol dicarboxylates are of the formula STR1 where A is the residue of certain dicarboxyic acids, R3 is H or (C1 -C3), n is zero or 1 such that when n is zero R is P or B and R1 is the residue of certain esters, H or a salt thereof; and when n is 1, one of R and R1 is P and the other is B, and P is STR2 where R2 is H or certain acyl groups, and B is the residue of a beta-lactamase inhibiting carboxylic acid; a method for their use, pharmaceutical compositions thereof and intermediates useful in their production.
Synthesis of Pyrazinamide
Rao, A. V. Rama,Yadav, J. S.,Ravichandran, K.,Sahasrabudhe, A. B.,Chaurassia, S. S.
, p. 850 (2007/10/02)
The key intermediate, pyrazinoic acid (III) in the synthesis of pyrazinamide has been prepared starting from 2,3-dibromsuccinic acid.
