Read by QxMD icon Read

ketones aerobic

Arunachalam Sagadevan, Vaibhav Pramod Charpe, Ayyakkannu Ragupathi, Kuo-Chu Hwang
Direct oxidative coupling of phenols and terminal alkynes were achieved at room temperature by visible light-mediated copper-catalyzed process. This method allows for regioselective synthesis of hydroxyl-functionalized aryl and alkyl ketones from simple phenols and phenylacetylene via CC triple bond cleavage. 47 examples were presented. From synthetic point view, this protocol offers an efficient synthetic route for preparation of pharmaceutical drugs, such as, pitofenone and fenofibrate.
February 8, 2017: Journal of the American Chemical Society
Christian-Alexandre Castellano, Nancy Paquet, Isabelle J Dionne, Hélène Imbeault, Francis Langlois, Etienne Croteau, Sébastien Tremblay, Mélanie Fortier, J Jacques Matte, Guy Lacombe, Tamás Fülöp, Christian Bocti, Stephen C Cunnane
BACKGROUND: Aerobic training has some benefits for delaying the onset or progression of Alzheimer's disease (AD). Little is known about the implication of the brain's two main fuels, glucose and ketones (acetoacetate), associated with thesebenefits. OBJECTIVE: To determine whether aerobic exercise training modifies brain energy metabolism in mild AD. METHODS: In this uncontrolled study, ten patients with mild AD participated in a 3-month, individualized, moderate-intensity aerobic training on a treadmill (Walking)...
February 1, 2017: Journal of Alzheimer's Disease: JAD
Zhongyan Hu, Jinhuan Dong, Yang Men, Yifei Li, Xianxiu Xu
A DBU-catalyzed aerobic oxidative Robinson annulation of 2-isocyanochalcones with active methylene ketones was developed for the expedient synthesis of phenanthridines in high to excellent yields. This unprecedented multistep domino reaction represents a new strategy for the construction of this tricyclic scaffold by the sequential formation of two rings and three C-C bonds in a single operation at room temperature.
January 20, 2017: Chemical Communications: Chem Comm
Matteo Vergati, Eriseld Krasniqi, Girolamo Del Monte, Silvia Riondino, Doriana Vallone, Fiorella Guadagni, Patrizia Ferroni, Mario Roselli
Pre-clinical and clinical studies have investigated the role of a dysregulated metabolism in the sustainability of tumor initiation and progression. One of the most familiar metabolic alterations encountered in several types of cancers is the upregulation of glycolysis, which is also maintained in conditions of normal oxygen tension (aerobic glycolysis, Warburg effect) while oxidative phosphorylation is apparently reduced. As a result, cancer cells convert most incoming glucose to lactate. Although more rapid, adenosine triphosphate (ATP) production by glycolysis is less efficient in terms of ATP generated per unit of glucose consumed than oxidative phosphorylation...
January 16, 2017: Current Medicinal Chemistry
Claire Deville, Vickie McKee, Christine J McKenzie
The methylene group of the ligand 1,2-di(pyridin-2-yl)-ethanone oxime (dpeo) is slowly oxygenated by the O2 in air under ambient conditions when [Cu(dpeo)2](ClO4)2 is dissolved in ethanol or acetonitrile. An initial transient ketone product, 2-(hydroxyimino)-1,2-di(pyridine-2-yl)ethanone, (hidpe) was characterized in the heteroleptic copper(ii) complex [Cu(bpca)(hidpe)](ClO4). The co-ligand in this complex, N-(2'-pyridylcarbonyl)pyridine-2-carboximidate (bpca(-)), is derived from a copper-promoted Beckmann rearrangement of hidpe...
December 19, 2016: Dalton Transactions: An International Journal of Inorganic Chemistry
Yuchao Deng, Xiao-Jing Wei, Hui Wang, Yuhan Sun, Timothy Noël, Xiao Wang
A photocatalytic method for the aerobic oxidative cleavage of C=C bonds has been developed. Electron-rich aromatic disulfides were employed as photocatalyst. Upon visible-light irradiation, typical mono- and multi-substituted aromatic olefins could be converted into ketones and aldehydes at ambient temperature. Experimental and computational studies suggest that a disulfide-olefin charge-transfer complex is possibly responsible for the unconventional dissociation of S-S bond under visible light.
December 9, 2016: Angewandte Chemie
Katsumi Iizuka
Carbohydrate-response element-binding protein (ChREBP) has been identified as a transcription factor that binds to carbohydrate response element in the promoter of pyruvate kinase, liver and red blood cells. ChREBP is activated by metabolites derived from glucose and suppressed by adenosine monophosphate (AMP), ketone bodies and cyclic cAMP. ChREBP regulates gene transcription related to glucose and lipid metabolism. Findings from knockout mice and human subjects suggest that ChREBP helps to induce hepatic steatosis, dyslipidemia, and glucose intolerance...
February 2017: Biochimica et Biophysica Acta
Sophia M Raefsky, Mark P Mattson
An important concept in neurobiology is "neurons that fire together, wire together" which means that the formation and maintenance of synapses is promoted by activation of those synapses. Very similar to the effects of the stress of exercise on muscle cells, emerging findings suggest that neurons respond to activity by activating signaling pathways (e.g., Ca(2+), CREB, PGC-1α, NF-κB) that stimulate mitochondrial biogenesis and cellular stress resistance. These pathways are also activated by aerobic exercise and food deprivation, two bioenergetic challenges of fundamental importance in the evolution of the brains of all mammals, including humans...
January 2017: Free Radical Biology & Medicine
Daichi Yoshii, Xiongjie Jin, Takafumi Yatabe, Jun-Ya Hasegawa, Kazuya Yamaguchi, Noritaka Mizuno
In the presence of Au nanoparticles supported on manganese oxide OMS-2 (Au/OMS-2), various kinds of β-heteroatom-substituted α,β-unsaturated ketones (heteroatom = N, O, S) can be synthesized through α,β-dehydrogenation of the corresponding saturated ketones using O2 (in air) as the oxidant. The catalysis of Au/OMS-2 is truly heterogeneous, and the catalyst can be reused.
December 6, 2016: Chemical Communications: Chem Comm
Mark A Iron, Alex M Szpilman
Identifying the mechanism of a catalytic reaction is paramount for designing new and improved catalysts. Several alternative catalytic cycles for the copper/2,2,6,6-tetramethylpiperidine-N-oxyl (TEMPO)-catalyzed aerobic oxidation of alcohols to the corresponding aldehydes or ketones were examined using DFT at the SMD(CH3 CN)-RIJCOSX-DSD-PBEB95/def2-TZVP//DF-PBED3BJ /def2-SVP level of theory. A catalytic cycle in which TEMPO remains coordinated to copper throughout was identified as the most likely mechanism...
January 26, 2017: Chemistry: a European Journal
Florian Pünner, Yoshihiro Sohtome, Mikiko Sodeoka
We present a copper-catalyzed oxidative cyclization of β,γ-unsaturated hydrazones, utilizing molecular oxygen as a stoichiometric oxidant. The methodology provides distinct classes of pyrazoles simply by changing the reaction solvent. Tris-substituted pyrazoles, having a ketone functionality at the C-5 position, were obtained as the major product in ethanol, while di-substituted pyrazoles were predominantly formed in 1,1,1,3,3,3-hexafluoro-2-propanol.
December 1, 2016: Chemical Communications: Chem Comm
N Fahrenfeld, A Pruden, M Widdowson
Methyl ethyl ketone (MEK) is a common groundwater contaminant often present with more toxic compounds of primary interest. Because of this, few studies have been performed to determine the effect of microbial community structure on MEK biodegradation rates in aquifer sediments. Here, microcosms were prepared with aquifer sediments containing MEK following a massive spill event and compared to laboratory-spiked sediments, with MEK biodegradation rates quantified under mixed aerobic/anaerobic conditions. Biodegradation was achieved in MEK-contaminated site sediment microcosms at about half of the solubility (356 mg/L) with largely Firmicutes population under iron-reducing conditions...
October 20, 2016: Biodegradation
Chieh-Kai Chan, Yu-Lin Tsai, Yi-Ling Chan, Meng-Yang Chang
A new, four-step synthetic route for substituted 2,3-benzodiazepines 1, starting from aldehyde 4, was developed with excellent overall yields. This route included the 1,2-addition of various aromatic Grignard reagents to 4, PCC oxidation, and aerobic Wacker-type oxidation of the olefinic group of 6, followed by condensation of the resulting 1,5-dicarbonyl 7 with N2H4. Isoquinolones 9 were obtained when an aldehyde group was used instead of a ketone. The key structures were confirmed by X-ray single-crystal diffraction analysis...
October 21, 2016: Journal of Organic Chemistry
Qing-Bao Zhang, Yong-Liang Ban, Da-Gang Zhou, Pan-Pan Zhou, Li-Zhu Wu, Qiang Liu
We developed a visible-light driven oxo-acyloxylation of aryl alkenes with carboxylic acids and molecular oxygen. A metal-free photoredox system, consisting of an acridinium photocatalyst, an organic base, and molecular sieve (MS) 4 Å, promotes chemoselective aerobic photooxidation of aryl alkenes. This approach may provide a green, practical, and metal-free protocol for a wide range of α-acyloxy ketones.
October 21, 2016: Organic Letters
Jian Luo, Jian Zhang
A metal-free protocol to generate phthalimide-N-oxyl (PINO) radicals from N-hydroxyphthalimide (NHPI) via a photoinduced proton-coupled electron transfer process is reported. Using donor-substituted aromatic ketones, such as 4,4'-bis(diphenylamino)benzophenone (DPA-BP), PINO radicals are efficiently produced and subsequently utilized to functionalize olefins to afford a new class of alkyl hydroperoxides. The DPA-BP/NHPI/O2 photocatalytic system exhibits high efficiency toward the aerobic oxidation of β-O-4 lignin models...
October 7, 2016: Journal of Organic Chemistry
Q H Zhang, P K Jin, H H Ngo, X Shi, W S Guo, S J Yang, X C Wang, X Wang, M Dzakpasu, W N Yang, L Yang
This study examined the distribution of carbon sources in two anaerobic anoxic oxic (AAO) sewage treatment plants in Xi'an and investigated the transformation characteristics and utilization potential of slowly biodegradable organic matters (SBOM). Results indicated under anaerobic and aerobic conditions, SBOM could be transformed at a rate of 65% in 8h into more readily biologically utilizable substrates such as volatile fatty acids (VFAs), polysaccharides and proteins. Additionally, non-biodegradable humus-type substances which are difficult to biodegrade and readily accumulate, were also generated...
October 2016: Bioresource Technology
Gianluca Catucci, Ivan Zgrablic, Francesco Lanciani, Francesca Valetti, Daniela Minerdi, David P Ballou, Gianfranco Gilardi, Sheila J Sadeghi
BACKGROUND: Ar-BVMO is a recently discovered Baeyer-Villiger monooxygenase from the genome of Acinetobacter radioresistens S13 closely related to medically relevant ethionamide monooxygenase EtaA (prodrug activator) and capable of inactivating the imipenem antibiotic. METHODS: The co-substrate preference as well as steady-state and rapid kinetics studies of the recombinant purified protein were carried out using stopped-flow spectroscopy under anaerobic and aerobic conditions...
September 2016: Biochimica et Biophysica Acta
Lijun Gu, Cheng Jin, Hongtao Zhang, Jiyan Liu, Ganpeng Li, Zhi Yang
A Cu-mediated cyanation of aryl methyl ketones using cyanide anions as the nitrogen source was achieved to provide aromatic nitriles in moderate to good yields. The reaction tolerates a variety of synthetically important functional groups.
July 12, 2016: Organic & Biomolecular Chemistry
Paloma Navarro, Maria J Bueno, Ivana Zagorac, Tamara Mondejar, Jesus Sanchez, Silvana Mourón, Javier Muñoz, Gonzalo Gómez-López, Veronica Jimenez-Renard, Francisca Mulero, Navdeep S Chandel, Miguel Quintela-Fandino
Epithelial malignancies are effectively treated by antiangiogenics; however, acquired resistance is a major problem in cancer therapeutics. Epithelial tumors commonly have mutations in the MAPK/Pi3K-AKT pathways, which leads to high-rate aerobic glycolysis. Here, we show how multikinase inhibitor antiangiogenics (TKIs) induce hypoxia correction in spontaneous breast and lung tumor models. When this happens, the tumors downregulate glycolysis and switch to long-term reliance on mitochondrial respiration. A transcriptomic, metabolomic, and phosphoproteomic study revealed that this metabolic switch is mediated by downregulation of HIF1α and AKT and upregulation of AMPK, allowing uptake and degradation of fatty acids and ketone bodies...
June 21, 2016: Cell Reports
Theresa Sperger, Italo A Sanhueza, Franziska Schoenebeck
Computational chemistry has become an established tool for the study of the origins of chemical phenomena and examination of molecular properties. Because of major advances in theory, hardware and software, calculations of molecular processes can nowadays be done with reasonable accuracy on a time-scale that is competitive or even faster than experiments. This overview will highlight broad applications of computational chemistry in the study of organic and organometallic reactivities, including catalytic (NHC-, Cu-, Pd-, Ni-catalyzed) and noncatalytic examples of relevance to organic synthesis...
June 21, 2016: Accounts of Chemical Research
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"