- Smaller is smarter in a new cobalt(II) imide: Intermolecular interactions involving pyrazine versus the larger aromatic quinoxaline
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The synthesis of one symmetric and one non-symmetric ligand based on imide, quinoxaline and pyrazine moieties are reported. The symmetric ligand, N-(2-quinoxalylcarbonyl)-2-quinoxalinecarboxamide (Hquinoxquinox), is structurally characterised as Hquinoxquinox·d6DMSO. The non-symmetric ligand, N-(2-pyrazylcarbonyl)-2-quinoxalinecarboxamide (HLquinoxpz), was used to prepare the cobalt(II) complex [CoII(quinoxpz)2]·CH3OH, which was observed to remain high spin at 90 K. The structures of HLquinoxquinox·d6DMSO and [CoII(quinoxpz)2]·CH3OH are evaluated with regard to their potential to produce spin crossover (SCO) behaviour and for the construction of three-dimensional coordination polymers.
- Cowan, Matthew G.,Miller, Reece G.,Brooker, Sally
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- Azole-N-acetonitriles as carbonyl synthons: A one-pot preparation of heteroaryl amides from halides
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Azole-N-acetonitrile derivatives were utilized as synthons for an ambident carbonyl moiety via a strategy relying upon sequential base-mediated S NAr substitution of a 2-halo heterocycle, in situ oxidation, and amine displacement. This strategy allows prompt and efficient synthesis of N-containing heteroaryl amides directly from the corresponding halides via a one-pot process.
- Zhang, Zhongxing,Yin, Zhiwei,Kadow, John F.,Meanwell, Nicholas A.,Wang, Tao
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- Sodium cyanoborohydride-mediated direct conversion of some heterocyclic aldehydes to esters
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An exceptional oxidizing behavior of sodium cyanoborohydride is observed where electron-withdrawing heterocyclic aldehydes are directly converted to their corresponding esters on treatment of sodium cyanoborohydride in methanol. The spectral analysis and
- Goswami, Shyamaprosad,Hazra, Anita,Goh, Jia Hao,Fun, Hoong-Kun
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- Synthesis and antimycobacterial activity of pyrazine and quinoxaline derivatives
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A series of pyrazine and quinoxaline derivatives have been synthesized, and their activity against M. tuberculosis (Mtb) and Mycobacterium avium (MAC) are reported. The 4-acetoxy-benzyl ester of pyrazinoic acid and 4′-acetoxybenzyl 2-quinoxalinecarboxylate showed excellent activity against Mtb (MIC ranges of less than 1-6.25 μg/mL) but only modest activity against MAC (MICs of 4-32 μg/mL).
- Seitz, Lainne E.,Suling, William J.,Reynolds, Robert C.
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- First catalytic asymmetric hydrogenation of quinoxaline-2-carboxylates
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For the first time, the asymmetric hydrogenation of quinoxaline-2-carboxylates was performed successfully. The best catalysts are based on iridium complexes modified by chiral phosphorous ligands. Accelerated examination of ligands and catalysts has been undertaken by using a Chemspeed workstation, which enables carrying out, in parallel, eight independent catalytic reactions at the laboratory scale. Tetrahydroquinoxaline-2-carboxylates could be obtained with high yields and up to 74% ee.
- Maj, Anna M.,Heyte, Svetlana,Araque, Marcia,Dumeignil, Franck,Paul, Sébastien,Suisse, Isabelle,Agbossou-Niedercorn, Francine
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- One-step direct conversion of heterocyelie aldehydes to esters
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One-step direct conversion of a series of heteroeyelie aldehydes to heterocyclie esters is reported here by the use of thiamine hydrochloride as a catalyst in the absence of nitrogen atmosphere in a reasonably high yield. This method exclusively produces
- Goswami, Shyamaprosad,Hazra, Anita
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- Highly chemoselective deoxygenation of N-heterocyclic: N -oxides under transition metal-free conditions
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Because their site-selective C-H functionalizations are now considered one of the most useful tools for synthesizing various N-heterocyclic compounds, the highly chemoselective deoxygenation of densely functionalized N-heterocyclic N-oxides has received much attention from the synthetic chemistry community. Here, we provide a protocol for the highly chemoselective deoxygenation of various functionalized N-oxides under visible light-mediated photoredox conditions with Na2-eosin Y as an organophotocatalyst. Mechanistic studies imply that the excited state of the organophotocatalyst is reductively quenched by Hantzsch esters. This operationally simple technique tolerates a wide range of functional groups and allows high-yield, multigram-scale deoxygenation. This journal is
- Kim, Se Hyun,An, Ju Hyeon,Lee, Jun Hee
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supporting information
p. 3735 - 3742
(2021/05/04)
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- HETEROCYCLIC COMPOUNDS
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The present invention relates to compounds of the general formula (1) wherein the variables are defined as given in the description and claims. The invention further relates to uses of and to, processes and intermediates related to compounds of the general formula (I), wherein Q is wherein the substituents of I, Ia and Ib are as defined in description and claims.
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Page/Page column 74
(2018/07/29)
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- CALPAIN MODULATORS AND THERAPEUTIC USES THEREOF
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Disclosed herein are small molecule calpain modulator compositions, pharmaceutical compositions, the use and preparation thereof.
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Paragraph 1499
(2018/04/17)
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- Imidazole-containing condensed tricyclic compound and application thereof
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The invention discloses an imidazole-containing condensed tricyclic compound adopting the structure as shown in the formula (I) or pharmaceutically acceptable salts, stereisomers or prodrug molecules thereof. The imidazole-containing condensed tricyclic compound has the IDO1 activity regulation function, can enhance T-cell activation through blocking immune checkpoints IDO1, is used for treating IDO1-mediated immunosuppression, and therefore, can become an effective medicine for treating malignant tumors. When used together with checkpoint protein anti-body drugs or other anti-cancer drugs, the imidazole-containing condensed tricyclic compound can enhance the anti-cancer effect. Meanwhile, the imidazole-containing condensed tricyclic compound has the potential of effectively treating IDO1 abnormity related immunosuppressive diseases and has a high application value.
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Paragraph 0395
(2018/03/01)
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- Asymmetric hydrogenation of quinoxalines catalyzed by iridium/PipPhos
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A catalyst made in situ from the (cyclooctadiene)iridium chloride dimer, [Ir(COD)Cl]2, and the monodentate phosphoramidite ligand (S)-PipPhos was used in the enantioselective hydrogenation of 2- and 2,6-substituted quinoxalines. In the presence
- Mrsic, Natasa,Jerphagnon, Thomas,Minnaard, Adriaan J.,Feringa, Ben L.,De Vries, Johannes G.
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supporting information; experimental part
p. 2549 - 2552
(2009/12/27)
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- Simultaneous extraction and methylation of acidic analytes adsorbed onto ion exchange resins using supercritical carbon dioxide containing methyl iodide
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Methylation of a wide range of organic acids with methyl iodide was simply and efficiently performed on anion exchange resins with either supercritical carbon dioxide or acetonitrile as solvents. Analytes including chlorophenoxyacetic acids, pentachlorophenol, and quinoxaline-2-carboxylic acid were displaced from the resin in a single step as their methyl esters or ethers in high yield using the supercritical fluid extraction (SFE) system. The conversion of 2,4-D and 2,4,5-T (solutions of 100 and 35 ppb, respectively) to their methyl esters was complete in 30 min and gave yields of 92% and 99% with coefficients of variation of 10%. Analytes in up to 200 mL of aqueous solution could be trapped on 0.1 g of AG MP-1 anion exchange resin and derivatized and eluted using methyl iodide in supercritical carbon dioxide at 200 bar and 80°C. Less acidic compounds including albendazole, fenbendazole, triclabendazole, and sulfadimidine could also be derivatized on the resin under SFE conditions or in a quick and inexpensive procedure using acetonitrile; however, these compounds gave lower yields and multiple methylated products.
- Chatfield,Croft,Dang,Murby,Yu,Wells
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p. 945 - 951
(2007/10/02)
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- REACTIONS OF FUROXANS WITH PHOSPHORUS YLIDES
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Benzofuroxan (1) reacts with phosphorus ylide 2 to give benzimidazole derivatives 8 and 10, whereas reaction of 1 with ylide 12 furnishes quinoxaline 17 via an initial Wittig-type reaction.Similarly the reaction between the furoxanoquinoxalines 19a or 19b and the ylide 2 yielded compounds 22a and 22b, respectively.In these reactions as well as in the reactions of the above furoxans with other phosphorus ylides, a significant deoxygenation of the furoxans to furazans with subsequent oxidation of the ylides is generally observed.
- Argyropoulos, N. G.,Gallos, J. K.,Nicolaides, D. N.
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p. 3631 - 3636
(2007/10/02)
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