Tag: M.W=150-200

Minisci, Francesco; Recupero, Francesco; Punta, Carlo; Gambarotti, Cristian; Antonietti, Fabrizio; Fontana, Francesca; Pedulli, Gian Franco published the artcile< A novel, selective free-radical carbamoylation of heteroaromatic bases by Ce(IV) oxidation of formamide, catalyzed by N-hydroxyphthalimide>, Related Products of 5182-90-1, the main research area is carbamoylation heteroaromatic compound cerium oxidation formamide hydroxyphthalimide catalyst.

The Ce(IV)-NHPI system was used to generate a carbamoyl radical by oxidation of formamide; this nucleophilic radical has been successfully used in the carbamoylation of heteroaromatic bases.

Chemical Communications (Cambridge, United Kingdom) published new progress about Carbamoylation. 5182-90-1 belongs to class quinoxaline, and the molecular formula is C9H7N3O, Related Products of 5182-90-1.

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

Xu, Xinyu; Chen, Kezhi published the artcile< Palladium-catalyzed C-H activation of anisole with electron-deficient auxiliary ligands: a mechanistic investigation>, Category: quinoxaline, the main research area is anisole iodobenzene arylation mechanism PES Hammett constant.

Palladium-catalyzed selective C-H activation-functionalization has shown its significance in organic transformations. Recently, Yu et al. reported a palladium-norbornene co-catalyzed meta-selective arylation of electron-rich arenes. Although the exptl. observed site-selectivity has been successfully explained by the computational work of Dongju Zhang and co-workers, some important exptl. factors, such as the ligand choice and narrow substrate scope, remain unrationalized. In contrast to what has been suggested by Dongju Zhang, we proposed the palladium-silver dinuclear species as reactive intermediates in this work. The substituent effect was estimated to unravel the e-CMD nature of the rate-determining C-H activation step. Based on this realization, the exptl. observed substrate scope and ligand choice have also been rationalized.

Organic & Biomolecular Chemistry published new progress about Arylation catalysts. 23088-24-6 belongs to class quinoxaline, and the molecular formula is C9H5N3, Category: quinoxaline.

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

Lee, Hong Geun; Milner, Phillip J.; Placzek, Michael S.; Buchwald, Stephen L.; Hooker, Jacob M. published the artcile< Virtually Instantaneous, Room-Temperature [11C]-Cyanation Using Biaryl Phosphine Pd(0) Complexes>, Electric Literature of 23088-24-6, the main research area is cyanation carbon 11 aryl compound biaryl phosphine palladium catalyst; aryl nitrile carbon 11 labeled preparation.

A new radiosynthetic protocol for the preparation of [11C]aryl nitriles has been developed. This process is based on the direct reaction of in situ prepared L·Pd(Ar)X complexes (L = biaryl phosphine) with [11C]HCN. The strategy is operationally simple, exhibits a remarkably wide substrate scope with short reaction times, and demonstrates superior reactivity compared to previously reported systems. With this procedure, a variety of [11C]nitrile-containing pharmaceuticals, e.g., [11C]citalopram, were prepared with high radiochem. efficiency.

Journal of the American Chemical Society published new progress about Aromatic nitriles Role: SPN (Synthetic Preparation), PREP (Preparation) ([11C]-labeled). 23088-24-6 belongs to class quinoxaline, and the molecular formula is C9H5N3, Electric Literature of 23088-24-6.

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

Sangkanu, Suthinee; Rukachaisirikul, Vatcharin; Suriyachadkun, Chanwit; Phongpaichit, Souwalak published the artcile< Evaluation of antibacterial potential of mangrove sediment-derived actinomycetes>, Related Products of 5182-90-1, the main research area is sequence Streptomyces Staphylococcus Acinetobacter Chromobacterium antibacterial violacein; Anti-biofilm; Anti-violacein production; Antibacterial activity; Bioactive metabolites; Mangrove-derived actinomycetes; Streptomyces.

Actinomycetes are well-known as the source of bioactive metabolites. In this work, 16 out of 118 (13.6%) isolates of mangrove sediment-derived actinomycetes showed potential antibacterial activity against at least one bacterial strain. Five extracts from isolates AMA11, AMA12 and AMA21 exhibited a broad spectrum antibacterial activity against Staphylococcus aureus ATCC25923, Staphylococcus epidermidis ATCC35984, methicillin-resistant S. aureus (MRSA) SK1, Acinetobacter baumannii NPRC004 and Escherichia coli ATCC25922. Et acetate extract from the cells of AMA11 (AMA11CE) showed high activity against S. aureus and MRSA with the lowest min. inhibitory concentration (MIC) of 0.5μg ml-1. At concentration of four times its MIC, AMA11CE destroyed MRSA cells as analyzed by the SEM. In addition, AMA11CE, Et acetate extract from the culture broth of AMA12 (AMA12BE), AMA12CE and AMA21CE reduced violacein production in Chromobacterium violaceum. Furthermore, at concentrations lower than 10μg ml-1, all five extracts inhibited biofilm formation by S. epidermidis ATCC35984. The chem. anal. of the most active fraction from AMA11CE by GC-MS revealed the presence of 3-nitro-1,2-benzenedicarboxylic acid, hexadecanoic acid, quinoxaline-2-carboxamide and pentadecanoic acid. The 16S rDNA sequencing anal. revealed that these three potential isolates belonged to the genus Streptomyces. The results revealed that the actinomycetes from mangrove environment would be a good source of bioactive metabolites against pathogenic bacteria.

Microbial Pathogenesis published new progress about Acinetobacter baumannii. 5182-90-1 belongs to class quinoxaline, and the molecular formula is C9H7N3O, Related Products of 5182-90-1.

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

Rustenburg, Arien S.; Dancer, Justin; Lin, Baiwei; Feng, Jianwen A.; Ortwine, Daniel F.; Mobley, David L.; Chodera, John D. published the artcile< Measuring experimental cyclohexane-water distribution coefficients for the SAMPL5 challenge>, Electric Literature of 5182-90-1, the main research area is cyclohexane water SAMPL5 analysis; Blind challenge; Distribution coefficients; Partition coefficients; Predictive modeling; SAMPL.

Small mol. distribution coefficients between immiscible nonaqueuous and aqueous phases-such as cyclohexane and water-measure the degree to which small mols. prefer one phase over another at a given pH. As distribution coefficients capture both thermodn. effects (the free energy of transfer between phases) and chem. effects (protonation state and tautomer effects in aqueous solution), they provide an exacting test of the thermodn. and chem. accuracy of phys. models without the long correlation times inherent to the prediction of more complex properties of relevance to drug discovery, such as protein-ligand binding affinities. For the SAMPL5 challenge, we carried out a blind prediction exercise in which participants were tasked with the prediction of distribution coefficients to assess its potential as a new route for the evaluation and systematic improvement of predictive phys. models. These measurements are typically performed for octanol-water, but we opted to utilize cyclohexane for the nonpolar phase. Cyclohexane was suggested to avoid issues with the high water content and persistent heterogeneous structure of water-saturated octanol phases, since it has greatly reduced water content and a homogeneous liquid structure. Using a modified shake-flask LC-MS/MS protocol, we collected cyclohexane/water distribution coefficients for a set of 53 druglike compounds at pH 7.4. These measurements were used as the basis for the SAMPL5 Distribution Coefficient Challenge, where 18 research groups predicted these measurements before the exptl. values reported here were released. In this work, we describe the exptl. protocol we utilized for measurement of cyclohexane-water distribution coefficients, report the measured data, propose a new bootstrap-based data anal. procedure to incorporate multiple sources of exptl. error, and provide insights to help guide future iterations of this valuable exercise in predictive modeling.

Journal of Computer-Aided Molecular Design published new progress about pH. 5182-90-1 belongs to class quinoxaline, and the molecular formula is C9H7N3O, Electric Literature of 5182-90-1.

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

Citterio, Attilio; Gentile, Anna; Minisci, Francesco; Serravalle, Marco; Ventura, Susanna published the artcile< Polar effects in free-radical reactions. Carbamoylation and α-N-amidoalkylation of heteroaromatic bases by amides and hydroxylamine-O-sulfonic acid>, Electric Literature of 5182-90-1, the main research area is heterocycle carbamoylation amidoalkylation mechanism.

NH3+·, formed in the decomposition of H3N+OSO3- by Fe2+, generates carbamoyl and α-N-amidoalkyl radicals by H abstraction from formamide, alkylformamides, and N-alkylacetamides. Both carbamoyl and α-N-amidoalkyl radicals have a clear-cut nucleophilic character and selectively attack protonated heteroaromatic bases, e.g., 4-methylquinoline or quinoxaline, in the α-position or are oxidized by Fe(III) salts. Redox chain mechanisms are involved. The importance of the polar effects in the H abstraction, aromatic substitution, and oxidation by Fe(III) salt is discussed.

Journal of Organic Chemistry published new progress about Amidoalkylation. 5182-90-1 belongs to class quinoxaline, and the molecular formula is C9H7N3O, Electric Literature of 5182-90-1.

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

Minisci, Francesco; Gardini, G. P.; Galli, Remo; Bertini, F. published the artcile< New selective type of aromatic substitution: homolytic amidation>, SDS of cas: 5182-90-1, the main research area is heterocycle nitrogen homolytic amidation; homolytic amidation nitrogen heterocycle; amidation homolytic nitrogen heterocycle; nitrogen heterocycle homolytic amidation; heterocycle nitrogen homolytic amidation; carbamoylation homolytic nitrogen heterocycle; carbamoyl pyridines pyrazines; pyridines carbamoyl pyrazines; pyrazines carbamoyl pyridines; thiazoles imidazoles benzimidazoles amidation; imidazoles benzimidazoles thiazoles amidation; benzimidazoles imidazoles thiazoles amidation; carbamoyl radical nucleophilic character.

I, II (at least one of R1 and R2 is CONH2), and III are prepared by carbamoylation. Thus, 34% H2O2 soin. is added to quinoxaline and concentrated H2SO4 in HCONH2 at 10-15°. FeSO4.7H2O is added simultaneously, to give 97% 2-quinoxalinecarboxamide. Similarly prepared are I (R = H) and the following II (R, R1, and R2 given): H, CONH2, CONH2; H, CONH2, Et; (RR =)CH:CHCH:CH, CONH2, CONH2; (RR =) CH:CHCH:CH, CONH2, Me; (RR =) CH:CHCH:CH, Me, CONH2. Also prepared were 1-carbamoyl-isoquinoline, III (R = S), and III (R = NH).

Tetrahedron Letters published new progress about 5182-90-1. 5182-90-1 belongs to class quinoxaline, and the molecular formula is C9H7N3O, SDS of cas: 5182-90-1.

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

Liu, Luo-Yan; Qiao, Jennifer X.; Yeung, Kap-Sun; Ewing, William R.; Yu, Jin-Quan published the artcile< meta C-H Arylation of Electron-Rich Arenes: Reversing the Conventional Site Selectivity>, Computed Properties of 23088-24-6, the main research area is meta arylation electron rich arene mutually repulsive pyridine ligand; reverse site selectivity alkoxy aromatic compound arylation.

Controlling site selectivity of C-H activation without using a directing group remains a significant challenge. While Pd(II) catalysts modulated by a mutually repulsive pyridine-type ligand have been shown to favor the relatively electron-rich carbon centers of arenes, reversing the selectivity to favor palladation at the relatively electron-deficient positions has not been possible. Herein we report the first catalytic system that effectively performs meta C-H arylation of a variety of alkoxy aromatics including 2,3-dihydrobenzofuran and chroman with exclusive meta site selectivity, thus reversing the conventional site selectivity governed by native electronic effects. The identification of an effective ligand and modified norbornene (NBE-CO2Me), as well as taking advantage of the statistics, are essential for achieving the exclusive meta selectivity.

Journal of the American Chemical Society published new progress about Aromatic ethers Role: RCT (Reactant), SPN (Synthetic Preparation), RACT (Reactant or Reagent), PREP (Preparation). 23088-24-6 belongs to class quinoxaline, and the molecular formula is C9H5N3, Computed Properties of 23088-24-6.

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

Teng, Qing-Hu; Yao, Yan; Wei, Wen-Xiu; Tang, Hai-Tao; Li, Jia-Rong; Pan, Ying-Ming published the artcile< Direct C-H sulfenylation of quinoxalinones with thiols under visible-light-induced photocatalyst-free conditions>, Name: 7-Nitro-2(1H)-quinoxalinone, the main research area is arylthioquinoxalinone alkylthioquinoxalinone preparation; aerobic photochem oxidative sulfenylation quinoxalinone thiol.

Quinoxalinones underwent aerobic photochem. sulfenylation/cross-dehydrogenative coupling with thiols under blue LED irradiation without added photocatalyst in NMP to give aryl- and alkylthioquinoxalinones.

Green Chemistry published new progress about Aromatic thiols Role: RCT (Reactant), RACT (Reactant or Reagent). 89898-96-4 belongs to class quinoxaline, and the molecular formula is C8H5N3O3, Name: 7-Nitro-2(1H)-quinoxalinone.

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

Sasaki, Yoshio; Hatanaka, Minoru; Suzuki, Miyoko published the artcile< Proton magnetic resonance spectra in aromatic systems. XIII. Heteroaromatic series. 5. 6-Substituted quinoxalines>, Computed Properties of 23088-24-6, the main research area is quinoxalines hetervaroms PMR; hetervaroms quinoxalines PMR; PMR quinoxalines hetervaroms.

The chem. shifts of the ring 1H of 6-quinoxalines have been corrected for N anisotropy, N elec. field, and ring current effects. The corrected shifts have also been correlated with the substituent constants σπ, and those corresponding to the π-electron charge density-ρ-distributions were estimated, and converted to ρ values.

Yakugaku Zasshi published new progress about NMR (nuclear magnetic resonance). 23088-24-6 belongs to class quinoxaline, and the molecular formula is C9H5N3, Computed Properties of 23088-24-6.

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider