Category: 25983-14-6

Wang, Zhaolin published the artcileDiscovery and structure-activity relationships of small molecules that block the human immunoglobulin G-human neonatal Fc receptor (hIgG-hFcRn) protein-protein interaction, HPLC of Formula: 25983-14-6, the main research area is quinoxaline preparation hIgG hFcRn protein interaction antagonist autoimmune disease.

The neonatal Fc receptor, FcRn, prolongs the half-life of IgG in the serum and represents a potential therapeutic target for the treatment of autoimmune disease. Small mols. that block the protein-protein interactions of human IgG-human FcRn may lower pathogenic autoantibodies and provide effective treatment. A novel class of quinoxalines has been discovered as antagonists of the IgG:FcRn protein-protein interaction through optimization of a hit derived from a virtual ligand-based screen. Compound I was found to be the most potent with IC50 = 2 μM.

Bioorganic & Medicinal Chemistry Letters published new progress about Autoimmune disease. 25983-14-6 belongs to class quinoxaline, name is 2,3,6,7-Tetrachloroquinoxaline, and the molecular formula is C8H2Cl4N2, HPLC of Formula: 25983-14-6.

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

Morais, Victor M. F. published the artcileThermochemical study of chloropyrazines and chloroquinoxalines, Formula: C8H2Cl4N2, the main research area is enthalpy formation combustion vaporization sublimation chloropyrazine chloroquinoxaline; mol structure chloropyrazine chloroquinoxaline DFT.

The standard (p° = 0.1 MPa) molar enthalpies of formation for liquid 2-chloropyrazine and crystalline 2,6-dichloropyrazine, 2,3-dichloroquinoxaline and 2,3,6,7-tetrachloroquinoxaline were derived from the standard molar enthalpies of combustion, in oxygen, to yield CO2(g), N2(g), and HCl·600H2O(l), at the temperature T = 298.15 K, measured by rotating-bomb combustion calorimetry. The standard molar enthalpies of vaporization or of sublimation, at T = 298.15 K, were measured by Calvet microcalorimetry. D. functional theory with the B3LYP functional and two different basis sets, 6-31G* and 6-311G*, was used to optimize the geometries of all chloro-substituted pyrazines and some chloro-substituted quinoxalines. The calculation of the energy of isodesmic reactions allowed the estimation of the standard molar enthalpies of formation in the gas phase for all compounds, including some not studied exptl.

Journal of Chemical Thermodynamics published new progress about Combustion enthalpy. 25983-14-6 belongs to class quinoxaline, name is 2,3,6,7-Tetrachloroquinoxaline, and the molecular formula is C8H2Cl4N2, Formula: C8H2Cl4N2.

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

Ivanova, Bojidarka published the artcileQuinoxalines as potent selective CRFRs ligands for monitoring and brain diagnostic, HPLC of Formula: 25983-14-6, the main research area is quinoxaline CRFR ligand brain diagnostic; Brain diagnostic; CRFRs; Quinoxalines.

The paper highlighted quinoxalines as potent ligands to corticotropin-releasing factor receptor types 1 and 2. The content includes design and structure-activity relationship of 50 model substances to CRFR1, CRFR2α and CRF2β, resp. It is important to bear in mind, that our concept has based on challenging research task, designing for selective CRFRs ligands. Because,: (i) These macromols. can bond more than one ligand, thus causing for a distinct physiol. response; (ii) CRFRs also participate readily in protein-protein interactions; (iii) CRFRs have two step activation mechanism and; (iv) CRFR1 has low selectivity. In spite of, numerous research efforts, which have been devoted to the isolation of series peptidic and non-peptidic CRFRs agonists, the poor penetration across blood-brain barrier restricts, their wide application in the clin. practice. Furthermore, the biol. role of CRFR2 is not yet fully understood. For that reason, the studies of the structure-activity relationship have significant impact in the field. The great advantages of quinoxalines as prospective ligands are based on their: (a) One-step synthetic road, using mild exptl. conditions and, allowing to involve various functional groups in the mol. scaffold as well as good-to-excellent yields, employing Fischer and Hinsberg methods; (b) High selectivity to CRFRs sub-types and; (c) Tunable fluorescence emission within the frame of a large scale of the electromagnetic spectrum ∈ 500-700 nm.

Bioorganic Chemistry published new progress about Biological permeation. 25983-14-6 belongs to class quinoxaline, name is 2,3,6,7-Tetrachloroquinoxaline, and the molecular formula is C8H2Cl4N2, HPLC of Formula: 25983-14-6.

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

Alhayek, Alaa published the artcileDiscovery and Characterization of Synthesized and FDA-Approved Inhibitors of Clostridial and Bacillary Collagenases, SDS of cas: 25983-14-6, the main research area is FDA approved inhibitor clostridia bacillus collagenase antibacterial.

In view of the worldwide antimicrobial resistance (AMR) threat, new bacterial targets and anti-infective agents are needed. Since important roles in bacterial pathogenesis have been demonstrated for the collagenase H and G (ColH and ColG) from Clostridium histolyticum, collagenase Q1 and A (ColQ1 and ColA) from Bacillus cereus represent attractive antivirulence targets. Furthermore, repurposing FDA-approved drugs may assist to tackle the AMR crisis and was addressed in this work. Here, we report on the discovery of two potent and chem. stable bacterial collagenase inhibitors: synthesized and FDA-approved diphosphonates and hydroxamates. Both classes showed high in vitro activity against the clostridial and bacillary collagenases. The potent diphosphonates reduced B. cereus-mediated detachment and death of cells and Galleria mellonella larvae. The hydroxamates were also tested in a similar manner; they did not have an effect in infection models. This might be due to their fast binding kinetics to bacterial collagenases.

Journal of Medicinal Chemistry published new progress about Antibacterial agents. 25983-14-6 belongs to class quinoxaline, name is 2,3,6,7-Tetrachloroquinoxaline, and the molecular formula is C8H2Cl4N2, SDS of cas: 25983-14-6.

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

Smits, Rogier A. published the artcileFragment based design of new H4 receptor-ligands with anti-inflammatory properties in vivo, COA of Formula: C8H2Cl4N2, the main research area is methylpiperazin quinoxaline derivative preparation structure H4 receptor ligand antiinflammatory.

Using a previously reported flexible alignment model the authors have designed, synthesized, and evaluated a series of compounds at the human histamine H4 receptor (H4R) from which 2-(4-methyl-piperazin-1-yl)-quinoxaline (I) was identified as a new lead structure for H4R ligands. Exploration of the structure-activity relationship (SAR) of this scaffold led to the identification of 6,7-dichloro 3-(4-methylpiperazin-1-yl)quinoxalin-2(1H)-one (VUF 10214, II) and 2-benzyl-3-(4-methyl-piperazin-1-yl)quinoxaline (VUF 10148, III) as potent H4R ligands with nanomolar affinities. In vivo studies in the rat reveal that compound II has significant anti-inflammatory properties in the carrageenan-induced paw-edema model.

Journal of Medicinal Chemistry published new progress about Anti-inflammatory agents. 25983-14-6 belongs to class quinoxaline, name is 2,3,6,7-Tetrachloroquinoxaline, and the molecular formula is C8H2Cl4N2, COA of Formula: C8H2Cl4N2.

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

Ceccarelli, Stefano published the artcileImidazo[1,2-a]quinoxalin-4-amines: a novel class of nonxanthine A1-adenosine receptor antagonists, Synthetic Route of 25983-14-6, the main research area is imidazoquinoxalinamine preparation A1 adenosine receptor binding.

The syntheses and A1 adenosine receptor affinities of a number of imidazo[1,2-a]quinoxalin-4-amines, e.g., I, are reported. Structure-activity relationships within the series and in comparison with other similar tricyclic nonxanthine adenosine antagonists are discussed, leading to a putative common binding mode of these nitrogen-containing heterocycles to A1 adenosine receptors. Secondary amino compounds displayed the best affinities toward A1 receptors, while the tertiary amines were almost devoid of activity, thus suggesting a crucial role for the hydrogen bond-forming 4-NH group. Remarkably higher potencies for 1-Me and N-cyclopentyl derivatives were also found. I (IRFI 165) is the most potent compound in this series, having Ki(A1) = 7.9 nM. It is also provided with a good A1 selectivity both vs. A2a and A3 subtypes and was selected for further pharmacol. studies.

European Journal of Medicinal Chemistry published new progress about Adenosine A1 receptor antagonists. 25983-14-6 belongs to class quinoxaline, name is 2,3,6,7-Tetrachloroquinoxaline, and the molecular formula is C8H2Cl4N2, Synthetic Route of 25983-14-6.

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

Monte, Manuel J. S. published the artcileThermodynamic Study on the Sublimation of Six Substituted Quinoxalines, Computed Properties of 25983-14-6, the main research area is quinoxaline derivative sublimation thermodn mass spectrometry Knudsen effusion.

The Knudsen mass-loss effusion technique was used to measure the vapor pressures at different temperatures of the following substituted quinoxalines: 2-hydroxyquinoxaline, between 383.17 K and 399.15 K; 2-hydroxy-3-methylquinoxaline, between 375.16 K and 391.15K; 2,3-dichloroquinoxaline, between 313.15 K and 329.15 K; 2,3,6,7-tetrachloroquinoxaline, between 347.16 K and 361.17 K; 2,3-dimethylquinoxaline between 294.14 K and 308.14 K; 2,3-bis(bromomethyl)quinoxaline, between 351.14 K and 365.14 K. From the temperature dependence of the vapor pressure, the standard molar enthalpies of sublimation at the mean temperature of the exptl. range were derived by the Clausius-Clapeyron equation. From these results the standard molar enthalpies, entropies, and Gibbs functions of sublimation at T = 298.15 K were calculated An empirical equation for estimating vapor pressure-temperature data from enthalpies of sublimation values is presented.

Journal of Chemical and Engineering Data published new progress about Clapeyron equation (standard mol.). 25983-14-6 belongs to class quinoxaline, name is 2,3,6,7-Tetrachloroquinoxaline, and the molecular formula is C8H2Cl4N2, Computed Properties of 25983-14-6.

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

Podsiadly, Radoslaw published the artcileSynthesis and photochemical reaction of novel, visible-wavelength oxidizable polymerization sensitizer based on the 12H-quinoxalino[2,3-b][1,4]benzothiazine skeleton, Recommanded Product: 2,3,6,7-Tetrachloroquinoxaline, the main research area is quinoxalinobenzothiazine dye sensitized alkoxypyridinium photodecomposition initiator visible light photopolym; photolysis quinoxalinobenzothiazine visible light sensitizer alkoxypyridinium polymerization photoinitiator.

Novel dyes based on the 12H-quinoxalino[2,3-b] [1,4]benzothiazine skeleton were synthesized and subsequently characterized using 1H NMR. Their electrochem. and spectral properties, such as absorption and emission spectra, quantum yield of fluorescence, and quantum yield of singlet oxygen formation, were measured. These compounds were evaluated as sensitizers for alkoxypyridinium salt photodecomposition, and the results are discussed on the basis of the free energy change for electron transfer from benzothiazine dyes to alkoxypyridinium compounds Benzothiazine dyes are useful oxidizable sensitizers for N-alkoxypyridinium photoinitiators. The mechanism of the dye photobleaching is supported by time-dependent d. functional theory (TD-DFT) calculations and the quantum yields of sensitized proton formation. Photoredox pairs consisting of benzothiazine dyes and alkoxypyridinium salt were found to be effective initiation systems for free radical polymerization of Me acrylate and trimethylolpropane triacrylate (TMPTA) using visible light.

Journal of Photochemistry and Photobiology, A: Chemistry published new progress about Absorption spectra (photobleaching). 25983-14-6 belongs to class quinoxaline, name is 2,3,6,7-Tetrachloroquinoxaline, and the molecular formula is C8H2Cl4N2, Recommanded Product: 2,3,6,7-Tetrachloroquinoxaline.

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

Lippa, K. A. published the artcileNucleophilic Aromatic Substitution Reactions of Chloroazines with Bisulfide (HS-) and Polysulfides (Sn2-), Quality Control of 25983-14-6, the main research area is chloroazine nucleophilic aromatic substitution reaction bisulfide polysulfide; seawater pollution chloroazine natural remediation nucleophilic reaction bisulfide polysulfide.

Reactions of bisulfide and polysulfides with chloroazines (important constituents of agrochems. and textile dyes) were examined in aqueous solution at 25°. For atrazine, rates are first-order in polysulfide concentration, and polysulfide dianions are the principal reactive nucleophiles; no measurable reaction occurs with HS-. Second-order rate constants for reactions of an array of chloroazines with polysulfides are several orders of magnitude greater than for reactions with HS-. Transformation products indicate the substitution of halogen(s) by sulfur. Ring aza nitrogens substantially enhance reactivity through a combination of inductive and mesomeric effects, and electron-withdrawing or electron-donating substituents markedly enhance or diminish reactivity, resp. The overall second-order nature of the reaction, the products observed, and reactivity trends are all consistent with a nucleophilic aromatic substitution (SNAr) mechanism. Rate constants for reactions with HS- and Sn2- (n = 2-5) correlate only weakly with LUMO (LUMO) energies, suggesting that the electrophilicity of a chloroazine is not the sole determinant of its reactivity. When second-order rate constants are extrapolated to HS- and Sn2- concentrations reported in salt marsh pore waters, half-lives of minutes to years are obtained. Polysulfides in particular could play an important role in effecting abiotic transformations of chloroazines in hypoxic marine waters.

Environmental Science and Technology published new progress about Aquatic sediment pore water (salt marsh). 25983-14-6 belongs to class quinoxaline, name is 2,3,6,7-Tetrachloroquinoxaline, and the molecular formula is C8H2Cl4N2, Quality Control of 25983-14-6.

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

Mohan Saini, Kapil published the artcileTrifluoroacetic Acid Mediated One-Pot Synthesis of Furo-Fused Quinoxalines/Pyrazines, Synthetic Route of 25983-14-6, the main research area is furoquinoxaline preparation; dichloroquinoxaline alkyne cyclization copper palladium catalyst; furopyrazine preparation; pyrazine alkyne cyclization copper palladium catalyst.

A trifluoroacetic acid promoted step-economical one-pot approach to the synthesis of furo-fused quinoxalines/ I (R = C6H5, 4-CF3C6H4, thiophen-3-yl, etc.; R1, R2 = H, Me, Cl)/pyrazines II (R3 = 2-Me, 4-Et, 4-nBu, etc.) by the reaction of 2,3-dichloroquinoxalines such as 2,3-dichloroquinoxaline, 2,3-dichloro-6-methylquinoxaline, 2,3-dichloro-6,7-dimethylquinoxaline, 2,3,6,7-tetrachloroquinoxaline /2,3-dichloropyrazine with alkynes RCCH is described. The reaction involves a selective in-situ Sonogashira coupling step and a hydroxylation followed by a metal-free 5-endo-dig cyclization. Preliminary experiments show that trifluoroacetic acid acts as a source of oxygen for the oxyarylation step, and isotopic labeling studies support the proposal that the mechanistic pathway involves activation of the alkyne by the acidic medium. Various kinds of substituents are tolerated, which should prove valuable for structural and biol. investigations.

European Journal of Organic Chemistry published new progress about Alkynes, aryl Role: RCT (Reactant), RACT (Reactant or Reagent). 25983-14-6 belongs to class quinoxaline, name is 2,3,6,7-Tetrachloroquinoxaline, and the molecular formula is C8H2Cl4N2, Synthetic Route of 25983-14-6.

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider