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Sample records for beta di ketonate

  1. Polyfluorinated. cap alpha. ,. beta. -unsaturated ketons

    SciTech Connect

    Latypov, R.R.; Belogai, V.D.; Pashkevich, K.I.

    1986-07-10

    The ..cap alpha..,..beta..-unsaturated ketones (..cap alpha..,..beta..-UK), particularly those groups containing fluoroalkyl groups, are of interest as highly reactive compounds having two nonequivalent electrophilic centers. In the present investigation, by boiling polyfluorinated aldehydes with methylketones in glacial acetic acid, they have obtained for the first time the polyfluorinated ..beta..-hydroxy-ketones, the dehydration of which has been used to synthesize the corresponding polyfluorinated ..cap alpha..,..beta..-UK, and their structure and reactions with the nucleophiles NH/sub 3/, PhNH/sub 2/, MeOH have been studied. In the PMR spectra of the ..cap alpha..,..beta..-UK (X)-(XVI) two doublets of triplets are observed at 6.9 and 7.9 ppm, caused by the spin-spin coupling of the olefin protons with the CF/sub 2/ group of the substituent. For ..cap alpha..,..beta..-UK, apart from the cis-trans isomerism relative to the C=C bond, a rotational isomerism is possible, caused by rotation around the C-C single bond. The presence in the IR spectra of absorption bands from nonplanar torsion-deformation vibrations of C-H for a double bond (nu = 975-980 cm/sup -1/) and the high value of the spin-spin coupling constant of the olefin protons (J/sub HH/ = 15 Hz) indicate unambiguously the transconfiguration of the olefin protons.

  2. Manganese(II) complexes of substituted di-2-pyridyl ketone thiosemicarbazones: Structural and spectral studies

    NASA Astrophysics Data System (ADS)

    Philip, Varughese; Suni, V.; Kurup, Maliyeckal R. Prathapachandra; Nethaji, Munirathinam

    2006-05-01

    The reaction between manganese(II) acetate and two substituted thiosemicarbazones derived from di-2-pyridyl ketone (HL) in 1:2 molar ratio produces new complexes of general formula [MnL 2]. The thiosemicarbazone moiety in HL deprotonates and gets coordinated to Mn(II) through the azomethine nitrogen, one of the pyridyl nitrogens, and the thiolate sulfur in both the complexes. The crystal structure of [ MnL21] was established by single crystal X-ray diffraction and the compound crystallizes into a monoclinic lattice with P2 1/ c space group. Manganese(II) exists in a distorted octahedral geometry in the complexes.

  3. Fluorimetric determination of trace amounts of scandium with Di-2-pyridyl-ketone 2-furoylhydrazone

    SciTech Connect

    Cano Pavon, J.M.; Bosch Ojeda, C.; Garcia de Torres, A.; Salgado Ordonez, M. )

    1990-01-01

    The reaction of Di-2-pyridyl-ketone 2-furoylhydrazone (DPFH) with scandium in an aqueous ethanolic medium (4% v/v of ethanol) has been studied. A spectrofluorometric method based on the formation of a fluorescent complex is proposed for the determination of scandium. With excitation at 387 nm, the scandium(III) chelate has an emission maximum at 492 nm; the reaction is carried out at pH 6.5-7.5. The accuracy and precision of the method are demonstrated by the analysis of synthetic mixtures containing various amounts of scandium. 10 - 140 ng/ml of scandium can be determined with a relative error of {plus minus}1.3%.

  4. Mutagen production by chlorination of methylated alpha,beta-unsaturated ketones.

    PubMed

    Cheh, A M

    1986-01-01

    Mesityl oxide and isophorone, two beta-methylated-alpha,beta-unsaturated industrial solvent ketones, were found to be converted to mutagens by aqueous chlorination under conditions of pH and reactant concentration that may be relevant to waste water and drinking water chlorination. Chlorination of millimolar concentrations of isophorone generated mutagens at a pH as low as 8.5, while mutagens were formed from submillimolar concentrations of mesityl oxide at pH 8.5, or millimolar concentrations at pH 7.5. It is suggested that mutagen formation can occur via a haloform reaction at such low pH levels because of extended resonance stabilization of an intermediate carbanion. PMID:3945234

  5. Iodotrimethylsilane-promoted 1,4-addition of alkynylcopper reagents to {alpha}, {beta}-unsaturated ketones and aldehydes

    SciTech Connect

    Eriksson, M.; Iliefski, T.; Nilsson, M.; Olsson, T.

    1995-12-31

    In the presence of TMSI copper acetylides react with cyclic {alpha},{beta}-enones, some s-trans enones and also to {alpha},{beta}-unsaturated aldehydes to give {gamma},{delta}-acetylenic ketones via the silyl enol ethers. Conjugate addition of alkyl and alkenyl copper reagents is a very useful method for the formation of carbon-carbon bonds. However, the conjugate addition of alkynyl copper compounds has so far remained a difficult task. Other methods based on organometallic reagents derived from aluminium, boron, and zinc have been reported. This is the first example of conjugate addition with copper acetylides to {alpha},{beta}-unsaturated carbonyl compounds.

  6. Unusual isolation of a hemiaminal product from 4-cyclohexyl-3-thiosemicarbazide and di-2-pyridyl ketone: Structural and spectral investigations

    NASA Astrophysics Data System (ADS)

    Suni, V.; Kurup, M. R. Prathapachandra; Nethaji, Munirathinam

    2005-07-01

    Stable hemiaminal product was isolated as single crystals from the condensation reaction of di-2-pyridyl ketone with 4-cyclohexyl-3-thiosemicarbazide and structurally and spectrochemically characterized. The compound is the first report of a stable hemiaminal product of the condensation reaction of a substituted thiosemicarbazone. Spectral characterization was carried out using IR, UV-vis., 1H NMR, 13C NMR, COSY and HMQC. The compound crystallizes into a triclinic lattice with space group P-1. The molecule reveals a highly strained ZE conformation and a one-dimensional packing is effected by a network of intermolecular hydrogen bonding interactions in the unit cell.

  7. Chemistry of enol ethers. LXXXIV. Condensation of acetals of saturated aldehydes with 2-trimethylsilyloxy-1,3-dienes. Synthesis of /beta/-alkoxy-alkyl vinyl and divinyl ketones

    SciTech Connect

    Makin, S.M.; Nazarova, O.N.; Dymshakova, G.M.; Kundryutskova, L.A.

    1988-11-10

    The addition of the acetals of saturated aldehydes (formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde, and isobutyraldehyde) to 2-trimethylsilyloxy-4-methyl-1,3-pentadiene in the presence of aprotic acids (ZnCl/sub 2/, ZnBr/sub 2/, FeCl/sub 3/, SnCl/sub 4/, BF/sub 3/ /times/ OEt/sub 2/) takes place at positions 1, 2 of the diene system with the formation of /beta/-alkoxyalkyl vinyl ketones. The most effective catalysts of this reaction were stannic chloride and zinc bromide. The alkyl derivatives of divinyl ketones are formed when the obtained /beta/-alkoxyalkyl vinyl ketones are heated with p-toluenesulfonic acid.

  8. Synthesis of alpha,beta-unsaturated ketones as chalcone analogues via a S(RN)1 mechanism.

    PubMed

    Curti, Christophe; Gellis, Armand; Vanelle, Patrice

    2007-01-01

    An electron-transfer chain reaction between 2-nitropropane anion and alpha-bromoketones derived from nitrobenzene and nitrothiophene was demonstrated by mechanistic study and a specific convenient synthetic protocol. Thus, 2-bromo-1-(5-nitrothiophen-2-yl)ethanone or 2-bromo-1-(4-nitrophenyl)ethanone were reacted with several cyclic nitronate anions to form alpha,beta-unsaturated ketones via a S(RN)1 mechanism. This new method can be used to synthesize a wide variety of chalcone analogues. PMID:17851431

  9. Structural and spectral perspectives of a novel thiosemicarbazone synthesized from di-2-pyridyl ketone and 4-phenyl-3-thiosemicarbazide

    NASA Astrophysics Data System (ADS)

    Suni, V.; Prathapachandra Kurup, M. R.; Nethaji, Munirathinam

    2006-01-01

    A new thiosemicarbazone, HL is synthesized from di-2-pyridyl ketone and 4-phenyl-3-thiosemicarbazide and structurally and spectrochemically characterized. 1H NMR, 13C NMR, COSY, HMQC and IR spectra of the compound are studied and the proton magnetic resonance spectrum reveals some unprecedented observations. The thione form is predominant in the solid state, as supported by the crystal structure and IR data, while a thiol-thione equilibrium is proposed in the solution state by NMR studies. The compound crystallizes into a monoclinic lattice with space group C2/c and the ZE conformation is exhibited by the thiosemicarbazone. Intra- and intermolecular hydrogen-bonding interactions give rise to a two-dimensional packing in the crystal lattice.

  10. Highly regio- and stereoselective synthesis of alpha-(N-alkyl-N-p-toluenesulfonyl)-beta-bromo-ketones via Ni(OAc)2-catalyzed aminobromination of chalcones.

    PubMed

    Sun, Hao; Zhi, San-Jun; Han, Jian-Lin; Li, Guigen; Pan, Yi

    2010-03-01

    The combinations of N-methyl-p-toluenesulfonamide/NBS and N-ethyl-p-toluenesulfonamide/NBS were found to be good nitrogen/halogen resources for the aminohalogenation of alpha,beta-unsaturated ketones in the presence of Ni(OAc)(2) as the catalyst for the synthesis of vicinal haloamino ketone derivatives. The introduction of N-alkyl groups to the nitrogen resources resulted in excellent regio- and stereoselectivity for both electron-donating and electron-withdrawing group-attached unsaturated ketone substrates. The structure of the resulting products has been unambiguously confirmed by X-ray crystal structure analysis. PMID:20331646

  11. Artificial photosynthesis of. beta. -ketocarboxylic acids from carbon dioxide and ketones via enolate complexes of aluminum porphyrin

    SciTech Connect

    Hirai, Yasuhiro; Aida, Takuzo; Inoue, Shohei )

    1989-04-12

    Photochemical fixation of carbon dioxide is of much interest in connection with biological photosynthesis by green plants as well as from the viewpoint of carbon resource utilization. One of the important steps in the assimilation of carbon dioxide is the carboxylation of a carbonyl compound into ketocarboxylic acid, where the reaction proceeds via an enolate species as reactive intermediate. For example, in four carbon (C{sub 4}) pathway and Crassulacean acid metabolism (CAM) processes, pyruvate is converted with the aid of ATP into phosphoenolpyruvate, which is subsequently carboxylated to give oxaloacetate by the action of pyruvate carboxylase. In relation to this interesting biological process, some artificial systems have been exploited for the synthesis of {beta}-ketocarboxylic acid derivatives from carbon dioxide and ketones using nucleophiles such as metal carbonates, thiazolates, phenolates, alkoxides, and strong organic as well as inorganic basis, which promote the enolization of ketones in the intermediate step. We wish to report here a novel, visible light-induced fixation of carbon dioxide with the enolate complex of aluminum porphyrin, giving {beta}-ketocarboxylic acid under mild conditions.

  12. Formal [4+2] cycloaddition of di-tert-butyl 2-ethoxycyclobutane-1,1-dicarboxylate with ketones or aldehydes and tandem lactonization.

    PubMed

    Okado, Ryohei; Nowaki, Aya; Matsuo, Jun-Ichi; Ishibashi, Hiroyuki

    2012-01-01

    A catalytic amount of tin(IV) chloride catalyzed formal [4+2] cycloaddition reaction of di-tert-butyl 2-ethoxycyclobutane-1,1-carboxylate with ketones or aldehydes to give diethyl 6-ethoxydihydro-2H-pyran-3,3(4H)-dicarboxylates, whereas two equivalents of trimethylsilyl triflate promoted tandem [4+2] cycloaddition and lactonization to afford 3-oxo-2,6-dioxabicyclo[2.2.2]octane-4-carboxylate esters. PMID:22223370

  13. Conjugate addition of indoles to alpha,beta-unsaturated ketones using a Brønsted acid ionic liquid as an efficient catalyst.

    PubMed

    Yu, Chuan-Ji; Liu, Chen-Jiang

    2009-01-01

    The Brønsted acid ionic liquid [PyN(CH(2))(4)SO(3)H][p-CH(3)PhSO(3)] has been reported as an efficient catalyst for the Michael addition reaction of indoles to alpha,beta-unsaturated ketones. Satisfactory results were obtained, with excellent yields and a simple experimental procedure. The catalyst could be recycled and reused up to three times without any noticeable decrease in the catalytic activity. PMID:19783920

  14. Raspberry Ketone

    MedlinePlus

    Raspberry ketone is a chemical from red raspberries, as well as kiwifruit, peaches, grapes, apples, other berries, vegetables such as rhubarb, and the bark of yew, maple, and pine trees. People take raspberry ketone by mouth for ...

  15. Characterization of raspberry ketone/zingerone synthase, catalyzing the alpha, beta-hydrogenation of phenylbutenones in raspberry fruits.

    PubMed

    Koeduka, Takao; Watanabe, Bunta; Suzuki, Shiro; Hiratake, Jun; Mano, Jun'ichi; Yazaki, Kazufumi

    2011-08-19

    Phenylbutanone raspberry ketone, accumulating in the mature fruits of raspberry (Rubus idaeus), imparts the characteristic aroma to the fruits. Here we describe the isolation and characterization of raspberry ketone/zingerone synthase 1 (RZS1), which catalyzed the NADPH-dependent reduction of 4-hydroxybenzalacetone and 3-methoxy-4-hydroxybenzalacetone to raspberry ketone and zingerone (the latter not found in raspberry), respectively. Its apparent K(m) values for 4-hydroxybenzalacetone and NADPH were 88 μM and 202 μM, respectively. RZS1 preferred 4-hydroxybenzalacetone to 3-methoxy-4-hydroxybenzalacetone as a substrate by a factor of 1.7, and showed a 6-fold preference for 4-hydroxybenzalacetone over p-coumaraldehyde, and no activity for coniferaldehyde. Expression analysis of the RZS1 gene throughout the plant revealed that its transcript level was highest in mature fruits. We conclude that RZS1 is responsible for hydrogenation of the α,β-unsaturated double bond of phenylbutenones, the final step of the raspberry ketone biosynthesis, in the raspberry fruits. PMID:21802408

  16. Ketones urine test

    MedlinePlus

    Ketone bodies - urine; Urine ketones; Ketoacidosis - urine ketones test; Diabetic ketoacidosis - urine ketones test ... Urine ketones are usually measured as a "spot test." This is available in a test kit that ...

  17. Raspberry Ketone

    MedlinePlus

    Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely ... keep in mind that there is no reliable scientific evidence that raspberry ketone improves weight loss when ...

  18. Effect of the Ketone Body Beta-Hydroxybutyrate on the Innate Defense Capability of Primary Bovine Mammary Epithelial Cells

    PubMed Central

    Flinspach, Claudia; Pfaffl, Michael W.; Kliem, Heike

    2016-01-01

    Negative energy balance and ketosis are thought to cause impaired immune function and to increase the risk of clinical mastitis in dairy cows. The present in vitro study aimed to investigate the effect of elevated levels of the predominant ketone body β-hydroxybutyrate on the innate defense capability of primary bovine mammary epithelial cells (pbMEC) challenged with the mastitis pathogen Escherichia coli (E. coli). Therefore, pbMEC of healthy dairy cows in mid- lactation were isolated from milk and challenged in culture with 3 mM BHBA and E. coli. pbMEC stimulated with E. coli for 6 h or 30 h showed an up-regulation of several innate immune genes, whereas co-stimulation of pbMEC with 3 mM BHBA and E. coli resulted in the down-regulation of CCL2, SAA3, LF and C3 gene expression compared to the challenge with solely the bacterial stimulus. These results indicated that increased BHBA concentrations may be partially responsible for the higher mastitis susceptibility of dairy cows in early lactation. Elevated levels of BHBA in blood and milk during negative energy balance and ketosis are likely to impair innate immune function in the bovine mammary gland by attenuating the expression of a broad range of innate immune genes. PMID:27310007

  19. Synthesis and biological evaluation of phenolic 4,5-dihydroisoxazoles and 3-hydroxy ketones as estrogen receptor alpha and beta agonists.

    PubMed

    Poutiainen, Pekka K; Venäläinen, Tuomas A; Peräkylä, Mikael; Matilainen, Juha M; Väisänen, Sami; Honkakoski, Paavo; Laatikainen, Reino; Pulkkinen, Juha T

    2010-05-15

    In this work, 52 diphenyl-4,5-dihydroisoxazoles and -3-hydroxy ketones were prepared and their estrogen receptor alpha (ERalpha) and estrogen receptor beta (ERbeta) activities were explored in order to systematize and maximize their biological activity. The biological activity was firstly screened by using ERE reporter assay to find out how aromatic hydroxylation and methylation of the chiral centers of the compounds affect the ability of ER to mediate biological responses. For selected 19 compounds, the relative binding affinities (RBA, relative to 3,17beta-estradiol) and ability to induce transcription of primary E2 target gene pS2 in human MCF-7 breast cancer cells were determined. In the reporter assay, many compounds showed even stronger activity than E2 and some of them showed RBA larger than 1%. The highest RBAs were determined for the enantiomers of 1-hydroxy-6-(4-hydroxy-phenyl)-1-phenyl-hexan-3-one (50a and 50b). Isomer 50a showed high binding affinity both to ERalpha (with RBA approximately 200%) and ERbeta (with RBA approximately 60%), while the RBAs of 50b were ca. 40% of those. Some of the other compounds (with RBA approximately 1-16%) showed also notable ERalpha binding selectivity. When four most promising ligands (50a, 50b, 45a, and 45b) were studied with respect to their ability to induce the transcription of primary E2 target gene pS2, the compounds acted as agonists or partial agonists. Computer modeling was used to predict receptor binding conformations and to rationalize the RBA differences of the compounds. PMID:20430632

  20. Ketones blood test

    MedlinePlus

    ... Ketones - serum; Nitroprusside test; Ketone bodies - serum; Ketones - blood ... A blood sample is needed. ... When the needle is inserted to draw blood, some people feel slight ... there may be some throbbing or a slight bruise. This soon ...

  1. Kinetic glutathione chemoassay to quantify thiol reactivity of organic electrophiles--application to alpha,beta-unsaturated ketones, acrylates, and propiolates.

    PubMed

    Böhme, Alexander; Thaens, Diana; Paschke, Albrecht; Schüürmann, Gerrit

    2009-04-01

    Glutathione (GSH) is a soft nucleophile and, as such, can be used to sense the reactivity of electrophilic agents toward the thiol group and other electron-rich sites of molecular structures. A new kinetic GSH chemoassay is introduced that employs a photometric method to quantify GSH loss and enables an efficient determination of second-order rate constants, k(GSH), of the reaction between electrophilic substances and GSH. Comparison with an existing 2 h static assay shows that the new kinetic variant is superior with respect to the detectable range of electrophilic reactivity and to confounding factors such as additional GSH loss due to oxidation. Analysis of the chemoassay degradation kinetics provides insight into the characteristic reaction times and the contributions of GSH-electrophile Michael addition and GSH oxidation to the overall GSH loss. For 15 alpha,beta-unsaturated ketones, nine acrylates, and two propiolates acting as Michael acceptors, the measured k(GSH) values span ca. 5 orders of magnitude. Moreover, log k(GSH) correlates with the compounds' toxicity toward the ciliates Tetrahymena pyriformis in terms of 48 h log EC(50) (50% growth inhibition) values, yielding a squared correlation coefficient (r(2)) of 0.91 and a root-mean-square error of 0.30 log units. It shows that for these and related compounds, aquatic toxicity is driven by electrophilic reactivity. The findings demonstrate that the kinetic GSH chemoassay can be used as an efficient tool to analyze, interpret, and predict correspondingly reactive toxicity in the context of qualitative and quantitative structure-activity relationship studies and as a nonanimal tool of integrated testing strategies for REACH to screen compounds for excess toxicity. PMID:19317512

  2. Some properties and the inclusion behavior of three positional isomers of 6(1),6n-di-O-alpha-D-glucosyl-cyclomaltoheptaoses (beta-cyclodextrins).

    PubMed

    Okada, Y; Koizumi, K

    1998-02-01

    Three positional isomers of 6(1),6n-di-O-alpha-D-glucosyl-cyclomaltoheptaose [1,n-(G)2-beta CDs; n = 2-4] which existed in the digests with glucoamylase of the products from cyclomaltoheptaose (beta-cyclodextrin, beta CD) and maltose with Klebsiella pneumoniae pullulanase, were purified by HPLC. The solubilities of two isomers of those doubly branched beta CDs, 1,2- and 1,3-(G)2-beta CDs, in water were much higher than those of parent non-branched beta CD and mono-branched beta CD, 6-O-alpha-D-glucosyl-beta CD (G-beta CD), while the solubility of another isomer, 1,4-(G)2-beta CD, was significantly lower than these two isomers, though it was higher than that of beta CD. On the other hand, the solubilities of 1,2- and 1,3-isomers in 10, 30, and 50% (v/v) aqueous methanol at 25 degrees C were independent of methanol concentrations and their solubilities were the same as those in water at 25 degrees C. However, that of 1,4-isomer increased with increasing methanol concentrations. The hemolytic activities of 1,n-(G)2-beta CDs on human erythrocytes in isotonic solution were lower than those of G-beta CD and beta CD, and became weaker in the order of 1,4- > 1,2- > 1,3-isomers. The complex-forming abilities of 1,n-(G)2-beta CDs for digitoxin, digoxin, fluorometholone, flurbiprofen, hydrocortisone acetate, and norfloxacin were about the same as those of beta CD and G-beta CD, whereas reserpine was more difficult to include within 1,n-(G)2-beta CDs than beta CD and G-beta CD. Nevertheless, the solubilities of those guest compounds were much more enhanced by 1,n-(G)2-beta CDs and G-beta CD than by beta CD. PMID:9501468

  3. Enantioselective analysis of ketone bodies in patients with beta-ketothiolase deficiency, medium-chain acyl coenzyme A dehydrogenase deficiency and ketonemic vomiting.

    PubMed

    Heil, M; Podebrad, F; Prado, E; Beck, T; Mosand, A; Sewell, A C; Böhles, H; Lehnert, W

    2000-03-10

    Enantioselective multidimensional gas chromatography-mass spectrometry (enantio-MDGC-MS) is a valuable tool for the differentiation of enantiomers from complex matrices when present in trace amounts. The separation of chiral compounds provides further information on the diagnosis of diseases, and on normal and abnormal biochemical pathways. The formation of the normal urinary metabolite 3-hydroxy-2-methylbutanoic acid (HMBA), excreted in abnormally high amounts in beta-ketothiolase deficiency, is not absolutely clarified. Metabolic pathways involving this metabolite are isoleucine catabolism, as well as presumably beta-oxidation of fatty acids and ketogenesis. The latter two pathways are distinguishable in their enantioselectivity. Enantioselective analysis gives further information on interfering metabolic pathways and the selectivity of the enzyme(s) forming HMBA. Different ratios of the stereoisomers of HMBA in control urine samples and patients with beta-ketothiolase deficiency were detected. Analogous to HMBA urinary 3-hydroxybutanoic acid (HBA) was investigated in several diseases. The formation of HBA and HMBA is expected to result from the same or similar metabolic pathways. Differences in the enantiomeric ratio of HMBA may originate from the enantioselectivity of different enzyme systems. PMID:10755375

  4. Methyl isobutyl ketone (MIBK)

    Integrated Risk Information System (IRIS)

    Methyl Isobutyl Ketone ( MIBK ) ; CASRN 108 - 10 - 1 ; Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for

  5. Methyl ethyl ketone (MEK)

    Integrated Risk Information System (IRIS)

    Methyl ethyl ketone ( MEK ) ( CASRN 78 - 93 - 3 ) Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Nonc

  6. Transformation of 1-O-(indole-3-acetyl)-beta-D-glucose into di-O-(indole-3-acetyl)-D-glucose catalysed by enzyme preparations from corn seedlings.

    PubMed

    Szmidt-Jaworska, A; Kesy, J; Kopcewicz, J

    1997-01-01

    A new enzymatic activity, which catalyses formation in vitro of di-O-(indole-3-acetyl)-D-glucose from 1-O-(indole-3-acetyl)-beta-D-glucose has been found in extracts of Zea mays seedlings. The structure of di-O-(indole-3-acetyl)-D-glucose, not as yet described, has been assigned by GC-MS, 1H NMR and ammonolysis. PMID:9360710

  7. Listeria monocytogenes Strain-Specific Impairment of the TetR Regulator Underlies the Drastic Increase in Cyclic di-AMP Secretion and Beta Interferon-Inducing Ability

    PubMed Central

    Yamamoto, Takeshi; Hara, Hideki; Tsuchiya, Kohsuke; Sakai, Shunsuke; Fang, Rendong; Matsuura, Motohiro; Nomura, Takamasa; Sato, Fumihiko; Mitsuyama, Masao

    2012-01-01

    Among a number of laboratory strains of Listeria monocytogenes used in experimental infection, strain LO28 is highly capable of inducing robust beta interferon (IFN-β) production in infected macrophages. In this study, we investigated the molecular mechanism of the IFN-β-inducing ability of LO28 by comparing it with that of strain EGD, a low-IFN-β-inducing strain. It was found that LO28 secretes a large amount of IFN-β-inducing factor, which turned out to be cyclic di-AMP. The secretion of cyclic di-AMP was dependent on MdrT, a multidrug resistance transporter, and LO28 exhibited a very high level of mdrT expression. The introduction of a null mutation into mdrT abolished the ability of LO28 to induce IFN-β production. Examination of genes responsible for the regulation of mdrT expression revealed a spontaneous 188-bp deletion in tetR of LO28. By constructing recombinant strains of LO28 and EGD in which tetR from each strain was replaced, it was confirmed that the distinct ability of LO28 is attributable mostly to tetR mutation. We concluded that the strong IFN-β-inducing ability of LO28 is due to a genetic defect in tetR resulting in the overexpression of mdrT and a concomitant increase in the secretion of cyclic di-AMP through MdrT. PMID:22508860

  8. Ketone bodies as signaling metabolites

    PubMed Central

    Newman, John C.; Verdin, Eric

    2014-01-01

    Traditionally, the ketone body β-hydroxybutyrate (βOHB) has been looked upon as a carrier of energy from liver to peripheral tissues during fasting or exercise. However, βOHB also signals via extracellular receptors and acts as an endogenous inhibitor of histone deacetylases (HDACs). These recent findings support a model in which βOHB functions to link the environment, in this case the diet, and gene expression via chromatin modifications. Here, we review the regulation and functions of ketone bodies, the relationship between ketone bodies and calorie restriction, and the implications of HDAC inhibition by the ketone body βOHB in the modulation of metabolism, and diseases of aging. PMID:24140022

  9. Green organocatalytic α-hydroxylation of ketones.

    PubMed

    Voutyritsa, Errika; Theodorou, Alexis; Kokotos, Christoforos G

    2016-06-28

    An efficient and green method for the α-hydroxylation of substituted ketones has been developed. This method includes the in situ conversion of various ketones into the corresponding silyl enol ethers and their oxidation to the corresponding α-hydroxy ketones. Two protocols have been established leading either to protected α-hydroxy carbonyls or free α-hydroxy ketones. Both procedures are easy to follow and lead to good to high yields for a variety of ketones. PMID:26867154

  10. Inborn errors of ketone body utilization.

    PubMed

    Hori, Tomohiro; Yamaguchi, Seiji; Shinkaku, Haruo; Horikawa, Reiko; Shigematsu, Yosuke; Takayanagi, Masaki; Fukao, Toshiyuki

    2015-01-01

    Succinyl-CoA:3-ketoacid CoA transferase (SCOT) deficiency and mitochondrial acetoacetyl-CoA thiolase (beta-ketothiolase or T2) deficiency are classified as autosomal recessive disorders of ketone body utilization characterized by intermittent ketoacidosis. Patients with mutations retaining no residual activity on analysis of expression of mutant cDNA are designated as severe genotype, and patients with at least one mutation retaining significant residual activity, as mild genotype. Permanent ketosis is a pathognomonic characteristic of SCOT-deficient patients with severe genotype. Patients with mild genotype, however, may not have permanent ketosis, although they may develop severe ketoacidotic episodes similar to patients with severe genotype. Permanent ketosis has not been reported in T2 deficiency. In T2-deficient patients with severe genotype, biochemical diagnosis is done on urinary organic acid analysis and blood acylcarnitine analysis to observe characteristic findings during both ketoacidosis and non-episodic conditions. In Japan, however, it was found that T2-deficient patients with mild genotype are common, and typical profiles were not identified on these analyses. Based on a clinical study of ketone body utilization disorders both in Japan and worldwide, we have developed guidelines for disease diagnosis and treatment. These diseases are treatable by avoiding fasting and by providing early infusion of glucose, which enable the patients to grow without sequelae. PMID:25559898

  11. Thermotropic phase properties of 1,2-di-O-tetradecyl-3-O-(3-O-methyl- beta-D-glucopyranosyl)-sn-glycerol.

    PubMed Central

    Trouard, T P; Mannock, D A; Lindblom, G; Rilfors, L; Akiyama, M; McElhaney, R N

    1994-01-01

    The hydration properties and the phase structure of 1,2-di-O-tetradecyl-3-O(3-O-methyl-beta-D-glucopyranosyl)-sn-glycerol (3-O-Me-beta-D-GlcDAIG) in water have been studied via differential scanning calorimetry, 1H-NMR and 2H-NMR spectroscopy, and x-ray diffraction. Results indicate that this lipid forms a crystalline (Lc) phase up to temperatures of 60-70 degrees C, where a transition through a metastable reversed hexagonal (Hll) phase to a reversed micellar solution (L2) phase occurs. Experiments were carried out at water concentrations in a range from 0 to 35 wt%, which indicate that all phases are poorly hydrated, taking up < 5 mol water/mol lipid. The absence of a lamellar liquid crystalline (L alpha) phase and the low levels of hydration measured in the discernible phases suggest that the methylation of the saccharide moiety alters the hydrogen bonding properties of the headgroup in such a way that the 3-O-Me-beta-D-GlcDAIG headgroup cannot achieve the same level of hydration as the unmethylated form. Thus, in spite of the small increase in steric bulk resulting from methylation, there is an increase in the tendency of 3-O-Me-beta-D-GlcDAIG to form nonlamellar structures. A similar phase behavior has previously been observed for the Acholeplasma laidlawii A membrane lipid 1,2-diacyl-3-O-(6-O-acyl-alpha-D-glucopyranosyl)-sn-glycerol in water (Lindblom et al. 1993. J. Biol. Chem. 268:16198-16207). The phase behavior of the two lipids suggests that hydrophobic substitution of a hydroxyl group in the sugar ring of the glucopyranosylglycerols has a very strong effect on their physicochemical properties, i.e., headgroup hydration and the formation of different lipid aggregate structures. PMID:7811919

  12. Stereoselective titanium-mediated aldol reactions of a chiral lactate-derived ethyl ketone with ketones.

    PubMed

    Alcoberro, Sandra; Gómez-Palomino, Alejandro; Solà, Ricard; Romea, Pedro; Urpí, Fèlix; Font-Bardia, Mercè

    2014-01-17

    Aldol reactions of titanium enolates of lactate-derived ethyl ketone 1 with other ketones proceed in a very efficient and stereocontrolled manner provided that a further equivalent of TiCl4 is added to the reacting mixture. The scope of these reactions encompasses simple ketones such as acetone or cyclohexanone as well as other ketones that contain potential chelating groups such as pyruvate esters or α- and β-hydroxy ketones. PMID:24372372

  13. Studies on the Chemistry and Reactivity of α-Substituted Ketones in Isonitrile-Based Multicomponent Reactions

    PubMed Central

    Fan, Lijun; Adams, Ashley M.; Polisar, Jason G.; Ganem, Bruce

    2009-01-01

    Using the Passerini and Ugi reactions as representative tests, the utility of several α-substituted ketones R-CO-CH2-X (X= sulfonyloxy, acyloxy, azido, halo, hydroxy and sulfonyl) in isonitrile-based multicomponent reactions was explored. In a relative rate study (R= PhCH2CH2), each of the α-substituted ketones underwent Passerini condensation more rapidly than the parent ketone. Short, highly convergent routes to oxazoline, β-lactam, di-O-acylglyceramides, and other molecular frameworks were developed. PMID:18939871

  14. Trifluoromethyl ketones as inhibitors of the processionary moth sex pheromone.

    PubMed

    Parrilla, A; Guerrero, A

    1994-02-01

    Aliphatic and aromatic trifluoromethyl ketones have been evaluated in the laboratory and in the field as inhibitors of the pheromone response of the processionary moth Thaumetopoea pityocampa males. Among them, two compounds, (Z)-1,1,1-trifluoro-15-octadecen-13-yn-2-one and (Z)-1,1,1-trifluoro-16-nonadecen-14-yn-2-one, are closely related analogs of the natural pheromone (Z)-13-hexadecen-11-ynyl acetate. In the laboratory experiments, carried out by pre-exposure of males to vapors of the chemicals, alpha-naphthyl trifluoromethyl ketone, beta-naphthyl trifluoromethyl ketone, 1,1,1-trifluorotetradecan-2-one and (Z)-16-nonadecen-14-yn-2-one displayed notable blockage of the pheromone detection on EAG. The activity of 1,1,1-trifluorotetradecan-2-one is postulated to be due to the inhibition of the pheromone-degrading esterase. In general, the compounds have shown low specificity for the substrate and exhibited only a modest or null EAG intrinsic activity. In the field, benzyl trifluoromethyl ketone, trifluoroacetophenone, (Z)-1,1,1-trifluoro-15-octadecen-13-yn-2-one, (Z)-1,1,1-trifluoro-16-nonadecen-14-yn-2-one and beta-naphthyl trifluoroacetate showed a remarkable disruptant effect when mixed with the pheromone in 1:0.1, 1:1 and 1:10 ratio. (Z)-16-Nonadecen-14-yn-2-one has been found to be a modest agonist of the natural pheromone, exhibiting an attractant activity threefold lower than the parent molecule. PMID:8055254

  15. [The different notions about beta-oxidation of fatty acids in peroxisomes, peroxisomes and ketonic bodies. The diabetic, acidotic coma as an acute deficiency of acetyl-CoA and ATP].

    PubMed

    Kotkina, T I; Titov, V N; Parkhimovich, R M

    2014-03-01

    The mechanisms of beta-oxidation of fatty acids developed more than a century before have no compliance with actual physical chemical data. The oxidation of long-chain C 16:0 palmitic saturated fatty acid occurs not by sequential formation of eight molecules of acetyl-KoA but by force of formation of double bond and its hydrolysis on two short-chain C 8:0 fatty acids. Only short-chain fatty acids can become shorter under "chipping" of C 2-acetate with formation of C 4-butyric acid (butyrate) and its metabolites (beta-hidroxibutirate, acetoacetate, acetone). The critical moment of oxidation is a hydrolysis of acetoacetyl-KoA on two molecules of acetyl-KoA. The molecule of ATP is to be expended on hydrolysis. The foundation of nonspecific biological reaction of stress--ketoacidosis,--is a decrease in mitochondrions of acetyl-KoA pool formed both from glycogen and glucose and fatty acids. The oxalate acetate inputs into Krebs cycle inadequate amount of acetyl-KoA which limits synthesis of ATP. The insulin has no direct involvement into development of ketoacidosis but prepares conditions to facilitate nonspecific etiological factor to initiate diabetic ketoacidosis. These are the pooling of small amount of glycogen in cytozol and the predominance in cytozol of cells and adipocytes of palmitic triglycerides which are slowly hydrolyzed by hormone-dependent lipase to release non-esterified fatty acids into intercellular medium. The increase of their concentration in blood plasma precedes ketoacidosis which is developing in patients without diabetes mellitus too. When cells begin to oxidize unsaturated linoleic and linolenic acids with large number of double binds instead of medium-chain fatty acids, oleinic and palmitic fatty acids to support beta-oxidation in mitochondrions and synthesis of ATP the amount of butyric acid, beta-hidroxibutiryl-KoA and acetoacetyl-KoA increases and of acetyl-KoA decreases. The cause of fatal outcome is the development of metabolic acidosis

  16. Ketone body metabolism and cardiovascular disease

    PubMed Central

    Cotter, David G.; Schugar, Rebecca C.

    2013-01-01

    Ketone bodies are metabolized through evolutionarily conserved pathways that support bioenergetic homeostasis, particularly in brain, heart, and skeletal muscle when carbohydrates are in short supply. The metabolism of ketone bodies interfaces with the tricarboxylic acid cycle, β-oxidation of fatty acids, de novo lipogenesis, sterol biosynthesis, glucose metabolism, the mitochondrial electron transport chain, hormonal signaling, intracellular signal transduction pathways, and the microbiome. Here we review the mechanisms through which ketone bodies are metabolized and how their signals are transmitted. We focus on the roles this metabolic pathway may play in cardiovascular disease states, the bioenergetic benefits of myocardial ketone body oxidation, and prospective interactions among ketone body metabolism, obesity, metabolic syndrome, and atherosclerosis. Ketone body metabolism is noninvasively quantifiable in humans and is responsive to nutritional interventions. Therefore, further investigation of this pathway in disease models and in humans may ultimately yield tailored diagnostic strategies and therapies for specific pathological states. PMID:23396451

  17. EXTRACTION OF TETRAVALENT PLUTONIUM VALUES WITH METHYL ETHYL KETONE, METHYL ISOBUTYL KETONE ACETOPHENONE OR MENTHONE

    DOEpatents

    Seaborg, G.T.

    1961-08-01

    A process is described for extracting tetravalent plutonium from an aqueous acid solution with methyl ethyl ketone, methyl isobutyl ketone, or acetophenone and with the extraction of either tetravalent or hexavalent plutonium into menthone. (AEC)

  18. Ketones block amyloid entry and improve cognition in an Alzheimer's model.

    PubMed

    Yin, Jun Xiang; Maalouf, Marwan; Han, Pengcheng; Zhao, Minglei; Gao, Ming; Dharshaun, Turner; Ryan, Christopher; Whitelegge, Julian; Wu, Jie; Eisenberg, David; Reiman, Eric M; Schweizer, Felix E; Shi, Jiong

    2016-03-01

    Sporadic Alzheimer's disease (AD) is responsible for 60%-80% of dementia cases, and the most opportune time for preventive intervention is in the earliest stage of its preclinical phase. As traditional mitochondrial energy substrates, ketone bodies (ketones, for short), beta-hydroxybutyrate, and acetoacetate, have been reported to provide symptomatic improvement and disease-modifying activity in epilepsy and neurodegenerative disorders. Recently, ketones are thought as more than just metabolites and also as endogenous factors protecting against AD. In this study, we discovered a novel neuroprotective mechanism of ketones in which they blocked amyloid-β 42, a pathologic hallmark protein of AD, entry into neurons. The suppression of intracellular amyloid-β 42 accumulation rescued mitochondrial complex I activity, reduced oxidative stress, and improved synaptic plasticity. Most importantly, we show that peripheral administration of ketones significantly reduced amyloid burden and greatly improved learning and memory ability in a symptomatic mouse model of AD. These observations provide us insights to understand and to establish a novel therapeutic use of ketones in AD prevention. PMID:26923399

  19. Highly Diastereoselective Chelation-controlled Additions to α-Silyloxy Ketones

    PubMed Central

    Stanton, Gretchen R.; Koz, Gamze

    2011-01-01

    The polar Felkin-Anh, Cornforth, and Cram-chelation models predict that the addition of organometallic reagents to silyl–protected α–hydroxy ketones proceeds via a non-chelation pathway to give anti-diol addition products. This prediction has held true for the vast majority of additions reported in the literature and few methods for chelation-controlled additions of organometallic reagents to silyl–protected α–hydroxy ketones have been introduced. Herein, we present a general and highly diastereoselective method for the addition of dialkylzincs and (E)-di-, (E)-tri- and (Z)-disubstituted vinylzinc reagents to α-silyloxy ketones using alkyl zinc halide Lewis acids, RZnX, to give chelation-controlled products (dr ≥18:1). The compatibility of organozinc reagents with other functional groups makes this method potentially very useful in complex molecule synthesis. PMID:21534530

  20. Mild electrophilic trifluoromethylthiolation of ketones with trifluoromethanesulfanamide.

    PubMed

    Wu, Wei; Zhang, Xuxue; Liang, Fang; Cao, Song

    2015-07-01

    A straightforward and convenient approach for trifluoromethylthiolation of various acyclic and cyclic ketones with PhNHSCF3 is described. The reaction proceeds smoothly in the presence of acetyl chloride at room temperature and affords α-trifluoromethylthiolated ketones in fair to good yields. PMID:26030292

  1. Fueling Performance: Ketones Enter the Mix.

    PubMed

    Egan, Brendan; D'Agostino, Dominic P

    2016-09-13

    Ketone body metabolites serve as alternative energy substrates during prolonged fasting, calorie restriction, or reduced carbohydrate (CHO) availability. Using a ketone ester supplement, Cox et al. (2016) demonstrate that acute nutritional ketosis alters substrate utilization patterns during exercise, reduces lactate production, and improves time-trial performance in elite cyclists. PMID:27626197

  2. Exposure to di(n-butyl)phthalate and benzo(a)pyrene alters IL-1{beta} secretion and subset expression of testicular macrophages, resulting in decreased testosterone production in rats

    SciTech Connect

    Zheng Shanjun; Tian Huaijun; Cao Jia; Gao Yuqi

    2010-10-01

    Di(n-butyl)phthalate (DBP) and benzo(a)pyrene (BaP) are environmental endocrine disruptors that are potentially hazardous to humans. These chemicals affect testicular macrophage immuno-endocrine function and testosterone production. However, the underlying mechanisms for these effects are not fully understood. It is well known that interleukin-1 beta (IL-1{beta}), which is secreted by testicular macrophages, plays a trigger role in regulating Leydig cell steroidogenesis. The purpose of this study was to reveal the effects of co-exposure to DBP and BaP on testicular macrophage subset expression, IL-1{beta} secretion and testosterone production. Adult male Sprague-Dawley rats were randomly divided into seven groups; two groups received DBP plus BaP (DBP + BaP: 50 + 1 or 250 + 5 mg/kg/day) four groups received DBP or BaP alone (DBP: 50 or 250 mg/kg/day; BaP: 1 or 5 mg/kg/day), and one group received vehicle alone (control). After co-exposure for 90 days, the relative expression of macrophage subsets and their functions changed. ED2{sup +} testicular macrophages (reactive with a differentiation-related antigen present on the resident macrophages) were activated and IL-1{beta} secretion was enhanced. DBP and BaP acted additively, as demonstrated by greater IL-1{beta} secretion relative to each compound alone. These observations suggest that exposure to DBP plus BaP exerted greater suppression on testosterone production compared with each compound alone. The altered balance in the subsets of testicular macrophages and the enhanced ability of resident testicular macrophages to secrete IL-1{beta}, resulted in enhanced production of IL-1{beta} as a potent steroidogenesis repressor. This may represent an important mechanism by which DBP and BaP repress steroidogenesis.

  3. Fenofibrate Induces Ketone Body Production in Melanoma and Glioblastoma Cells

    PubMed Central

    Grabacka, Maja M.; Wilk, Anna; Antonczyk, Anna; Banks, Paula; Walczyk-Tytko, Emilia; Dean, Matthew; Pierzchalska, Malgorzata; Reiss, Krzysztof

    2016-01-01

    Ketone bodies [beta-hydroxybutyrate (bHB) and acetoacetate] are mainly produced in the liver during prolonged fasting or starvation. bHB is a very efficient energy substrate for sustaining ATP production in peripheral tissues; importantly, its consumption is preferred over glucose. However, the majority of malignant cells, particularly cancer cells of neuroectodermal origin such as glioblastoma, are not able to use ketone bodies as a source of energy. Here, we report a novel observation that fenofibrate, a synthetic peroxisome proliferator-activated receptor alpha (PPARa) agonist, induces bHB production in melanoma and glioblastoma cells, as well as in neurospheres composed of non-transformed cells. Unexpectedly, this effect is not dependent on PPARa activity or its expression level. The fenofibrate-induced ketogenesis is accompanied by growth arrest and downregulation of transketolase, but the NADP/NADPH and GSH/GSSG ratios remain unaffected. Our results reveal a new, intriguing aspect of cancer cell biology and highlight the benefits of fenofibrate as a supplement to both canonical and dietary (ketogenic) therapeutic approaches against glioblastoma. PMID:26869992

  4. Microbial production of natural raspberry ketone.

    PubMed

    Beekwilder, Jules; van der Meer, Ingrid M; Sibbesen, Ole; Broekgaarden, Mans; Qvist, Ingmar; Mikkelsen, Joern D; Hall, Robert D

    2007-10-01

    Raspberry ketone is an important compound for the flavour industry. It is frequently used in products such as soft drinks, sweets, puddings and ice creams. The compound can be produced by organic synthesis. Demand for "natural" raspberry ketone is growing considerably. However, this product is extremely expensive. Consequently, there is a remaining desire to better understand how raspberry ketone is synthesized in vivo, and which genes and enzymes are involved. With this information we will then be in a better position to design alternative production strategies such as microbial fermentation. This article focuses on the identification and application of genes potentially linked to raspberry ketone synthesis. We have isolated candidate genes from both raspberry and other plants, and these have been introduced into bacterial and yeast expression systems. Conditions have been determined that result in significant levels of raspberry ketone, up to 5 mg/L. These results therefore lay a strong foundation for a potentially renewable source of "natural" flavour compounds making use of plant genes. PMID:17722151

  5. A Novel Di-Leucine Motif at the N-Terminus of Human Organic Solute Transporter Beta Is Essential for Protein Association and Membrane Localization

    PubMed Central

    Xu, Shuhua; Soroka, Carol J.; Sun, An-Qiang; Backos, Donald S.; Mennone, Albert; Suchy, Frederick J.; Boyer, James L.

    2016-01-01

    The heteromeric membrane protein Organic Solute Transporter alpha/beta is the major bile acid efflux transporter in the intestine. Physical association of its alpha and beta subunits is essential for their polarized basolateral membrane localization and function in the transport of bile acids and other organic solutes. We identified a highly conserved acidic dileucine motif (-EL20L21EE) at the extracellular amino-tail of organic solute transporter beta from multiple species. To characterize the role of this protein interacting domain in the association of the human beta and alpha subunits and in membrane localization of the transporter, Leu20 and Leu21 on the amino-tail of human organic solute transporter beta were replaced with alanines by site-directed mutagenesis. Co-immunoprecipitation study in HEK293 cells demonstrated that substitution of the leucine residues with alanines prevented the interaction of the human beta mutant with the alpha subunit. Membrane biotinylation demonstrated that the LL/AA mutant eliminated membrane expression of both subunits. Computational-based modelling of human organic solute transporter beta suggested that the LL/AA mutation substantially alters both the structure and lipophilicity of the surface, thereby not only affecting the interaction with the alpha subunit but also possibly impacting the capacity of the beta subunit to traffick through the cell and interact with the membrane. In summary, our findings indicate that the dileucine motif in the extracellular N-terminal region of human organic solute transporter beta subunit plays a critical role in the association with the alpha subunit and in its polarized plasma membrane localization. PMID:27351185

  6. A Novel Di-Leucine Motif at the N-Terminus of Human Organic Solute Transporter Beta Is Essential for Protein Association and Membrane Localization.

    PubMed

    Xu, Shuhua; Soroka, Carol J; Sun, An-Qiang; Backos, Donald S; Mennone, Albert; Suchy, Frederick J; Boyer, James L

    2016-01-01

    The heteromeric membrane protein Organic Solute Transporter alpha/beta is the major bile acid efflux transporter in the intestine. Physical association of its alpha and beta subunits is essential for their polarized basolateral membrane localization and function in the transport of bile acids and other organic solutes. We identified a highly conserved acidic dileucine motif (-EL20L21EE) at the extracellular amino-tail of organic solute transporter beta from multiple species. To characterize the role of this protein interacting domain in the association of the human beta and alpha subunits and in membrane localization of the transporter, Leu20 and Leu21 on the amino-tail of human organic solute transporter beta were replaced with alanines by site-directed mutagenesis. Co-immunoprecipitation study in HEK293 cells demonstrated that substitution of the leucine residues with alanines prevented the interaction of the human beta mutant with the alpha subunit. Membrane biotinylation demonstrated that the LL/AA mutant eliminated membrane expression of both subunits. Computational-based modelling of human organic solute transporter beta suggested that the LL/AA mutation substantially alters both the structure and lipophilicity of the surface, thereby not only affecting the interaction with the alpha subunit but also possibly impacting the capacity of the beta subunit to traffick through the cell and interact with the membrane. In summary, our findings indicate that the dileucine motif in the extracellular N-terminal region of human organic solute transporter beta subunit plays a critical role in the association with the alpha subunit and in its polarized plasma membrane localization. PMID:27351185

  7. Ketone ester effects on metabolism and transcription

    PubMed Central

    Veech, Richard L.

    2014-01-01

    Ketosis induced by starvation or feeding a ketogenic diet has widespread and often contradictory effects due to the simultaneous elevation of both ketone bodies and free fatty acids. The elevation of ketone bodies increases the energy of ATP hydrolysis by reducing the mitochondrial NAD couple and oxidizing the coenzyme Q couple, thus increasing the redox span between site I and site II. In contrast, metabolism of fatty acids leads to a reduction of both mitochondrial NAD and mitochondrial coenzyme Q causing a decrease in the ΔG of ATP hydrolysis. In contrast, feeding ketone body esters leads to pure ketosis, unaccompanied by elevation of free fatty acids, producing a physiological state not previously seen in nature. The effects of pure ketosis on transcription and upon certain neurodegenerative diseases make approach not only interesting, but of potential therapeutic value. PMID:24714648

  8. Stereoselective Formation of Fully Substituted Ketone Enolates.

    PubMed

    Haimov, Elvira; Nairoukh, Zackaria; Shterenberg, Alexander; Berkovitz, Tiran; Jamison, Timothy F; Marek, Ilan

    2016-04-25

    The application of stereochemically defined acyclic fully substituted enolates of ketones to the enantioselective synthesis of quaternary carbon stereocenters would be highly valuable. Herein, we describe an approach leading to the formation of several new stereogenic centers through a combined metalation-addition of a carbonyl-carbamoyl transfer to reveal in situ stereodefined α,α-disubstituted enolates of ketone as a single stereoisomer. This approach could produce a series of aldol and Mannich products from enol carbamate with excellent diastereomeric ratios. PMID:27027778

  9. Reaction of phenol with methyl 1-adamantyl ketone in the presence of aluminum phenolate

    SciTech Connect

    Kozlikovskii, Ya.B.; Chernyaev, B.V.; Yurchenko, A.G.

    1988-07-20

    The condensation of phenol with methyl 1-adamantyl ketone in the presence of aluminum phenolate leads to the formation of 1-(1-adamantyl)-1-(2-hydroxyphenyl)-ethene, 1-(1-adanamtyl)-1-(4-hydroxyphenyl)ethene, 3-methyl-2,3-(3,4-homoadamantano)-2,3-dihydrobenzofuran, and also the dimer and trimer of the initial ketone, i.e., 1,3-di(1-adamantyl)-2-buten-1-one and 1,3,5-tri(1-adamantyl)benzene. In an acidic medium 3-methyl-2,3-(3,4-homoadamantano)-2,3-dihydrobenzofuran is in equilibrium with 1-(1-adamantyl)-1-(2-hydroxyphenyl)ethene.

  10. The Conversion of Carboxylic Acids to Ketones: A Repeated Discovery

    ERIC Educational Resources Information Center

    Nicholson, John W.; Wilson, Alan D.

    2004-01-01

    The conversion of carboxylic acids to ketones is a useful chemical transformation with a long history. Several chemists have claimed that they discovered the conversion of carboxylic acids to ketones yet in fact the reaction is actually known for centuries.

  11. Asymmetric reduction of prochiral ketones to chiral alcohols catalyzed by plants tissue.

    PubMed

    Yang, Zhong-Hua; Zeng, Rong; Yang, Gai; Wang, Yu; Li, Li-Zhen; Lv, Zao-Sheng; Yao, Man; Lai, Bin

    2008-09-01

    As an important organic compound, chiral alcohols are the key chiral building blocks to many single enantiomer pharmaceuticals. Asymmetric reduction of the corresponding prochiral ketones to produce the chiral alcohols by biocatalysis is one of the most promising routes. Asymmetric reduction of different kinds of non-natural prochiral ketones catalyzed by various plants tissue was studied in this work. Acetophenone, 4'-chloroacetophenone and ethyl 4-chloroacetoacetate were chosen as the model substrates for simple ketone, halogen-containing aromatic ketone and beta-ketoesters, respectively. Apple (Malus pumila), carrot (Daucus carota), cucumber (Cucumis sativus), onion (Allium cepa), potato (Soanum tuberosum), radish (Raphanus sativus) and sweet potato (Ipomoea batatas) were chosen as the biocatalysts. It was found that these kinds of prochiral ketoness could be reduced by these plants tissue with high enantioselectivity. Both R- and S-form configuration chiral alcohols could be obtained. The e.e. and chemical yield could reach about 98 and 80% respectively for acetophenone and 4'-chloroacetophenone reduction reaction with favorable plant tissue. And the e.e. and yield for ethyl 4-chloroacetoacetate reduction reaction was about 91 and 45% respectively. PMID:18548304

  12. 40 CFR 721.4925 - Methyl n-butyl ketone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Methyl n-butyl ketone. 721.4925... Substances § 721.4925 Methyl n-butyl ketone. (a) Chemical substance and significant new use subject to reporting. (1) The chemical substance methyl n-butyl ketone, CAS Number 591-78-6, is subject to...

  13. 40 CFR 721.4925 - Methyl n-butyl ketone.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Methyl n-butyl ketone. 721.4925... Substances § 721.4925 Methyl n-butyl ketone. (a) Chemical substance and significant new use subject to reporting. (1) The chemical substance methyl n-butyl ketone, CAS Number 591-78-6, is subject to...

  14. 40 CFR 721.4925 - Methyl n-butyl ketone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Methyl n-butyl ketone. 721.4925... Substances § 721.4925 Methyl n-butyl ketone. (a) Chemical substance and significant new use subject to reporting. (1) The chemical substance methyl n-butyl ketone, CAS Number 591-78-6, is subject to...

  15. 40 CFR 721.4925 - Methyl n-butyl ketone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Methyl n-butyl ketone. 721.4925... Substances § 721.4925 Methyl n-butyl ketone. (a) Chemical substance and significant new use subject to reporting. (1) The chemical substance methyl n-butyl ketone, CAS Number 591-78-6, is subject to...

  16. Nickel catalyzed α-arylation of ketones with aryltrimethylammonium triflates.

    PubMed

    Li, Jing; Wang, Zhong-Xia

    2016-08-21

    Nickel-catalyzed α-arylation of ketones involving aromatic C-N cleavage has been accomplished. Intermolecular coupling of aromatic ketones with a variety of aryltrimethylammonium triflates was achieved in the presence of Ni(COD)2, IPr·HCl, and LiOBu(t), giving α-arylated ketones in reasonable to excellent yields. PMID:27443786

  17. Vapor pressures and gas-film coefficients for ketones

    USGS Publications Warehouse

    Rathbun, R.E.; Tai, D.Y.

    1987-01-01

    Comparison of handbook vapor pressures for seven ketones with more recent literature data showed large differences for four of the ketones. Gas-film coefficients for the volatilization of these ketones from water determined by two different methods were in reasonable agreement. ?? 1987.

  18. Relaxation behavior in model compounds of poly(aryl-ether-ketone-ketone) as revealed by dielectric spectroscopy

    NASA Astrophysics Data System (ADS)

    Ezquerra, T. A.; Zolotukhin, M.; Privalko, V. P.; Baltá-Calleja, F. J.; Nequlqueo, G.; García, C.; de la Campa, J. G.; de Abajo, J.

    1999-05-01

    The relaxation behavior of a series of ether-ketone oligomers, considered as model compounds of poly(ether-ketone-ketone), was studied by means of dielectric spectroscopy. The dynamics of the α relaxation of ether-ketone model compounds as compared with that of poly(arylether-ketone-ketone) (PEKK) (50/50), shows up differences which can be attributed to the variation of inter- and intramolecular correlations with the chain length. Model compounds exhibit a nearly similar degree of cooperativity regardless the differences in Tg values. The PEKK (50/50) polymer exhibits stronger cooperativity than the oligomers suggesting that in poly(ether-ketone-ketone)s molecular motions above Tg extend to more than one monomeric unit.

  19. Ketone-body utilization by homogenates of adult rat brain

    SciTech Connect

    Lopes-Cardozo, M.; Klein, W.

    1982-06-01

    The regulation of ketone-body metabolism and the quantitative importance of ketone bodies as lipid precursors in adult rat brain has been studied in vitro. Utilization of ketone bodies and of pyruvate by homogenates of adult rat brain was measured and the distribution of /sup 14/C from (3-/sup 14/C)ketone bodies among the metabolic products was analysed. The rate of ketone-body utilization was maximal in the presence of added Krebs-cycle intermediates and uncouplers of oxidative phosphorylation. The consumption of acetoacetate was faster than that of D-3-hydroxybutyrate, whereas, pyruvate produced twice as much acetyl-CoA as acetoacetate under optimal conditions. Millimolar concentrations of ATP in the presence of uncoupler lowered the consumption of ketone bodies but not of pyruvate. Indirect evidence is presented suggesting that ATP interferes specifically with the mitochondrial uptake of ketone bodies. Interconversion of ketone bodies and the accumulation of acid-soluble intermediates (mainly citrate and glutamate) accounted for the major part of ketone-body utilization, whereas only a small part was oxidized to CO/sub 2/. Ketone bodies were not incorporated into lipids or protein. We conclude that adult rat-brain homogenates use ketone bodies exclusively for oxidative purposes.

  20. Synthesis and characterization of poly(ether ketone)s containing phosphorus and fluorine

    SciTech Connect

    Youngman, P.W.; Fitch, J.W.; Cassidy, P.E. |

    1996-10-01

    Because of the excellent properties exhibited by fluorinated poly(ether ketone)s, modifications were sought to further improve this polymer toward atomic oxygen resistance. For this purpose a phosphorous-containing monomer [bis(4-fluorophenyl)phenyl phosphine oxide] was synthesized and incorporated into a poly(ether ketone) backbone by reaction with 2,2-bis[4-(4-fluorobenzoyl)phenyl]hexafluoropropane in varying proportions with bisphenol AF to produce polymers with different amounts of the phosphine oxide repeating unit in the backbone. Colorless, film-forming materials were produced with a slight increase in Tg due to the phosphine oxide function. The incorporation of this moiety also resulted in a very small increase in the dielectric constant and an improved resistance to atomic oxygen ablation.

  1. Suggested involvement of ketone bodies in the pathogenesis of the metabolic syndrome.

    PubMed

    Alexandre, Adolfo

    2013-05-01

    Untreated brain mitochondria are strong producers of H2O2. High peroxide production (in the presence of glutamate and pyruvate) is strictly succinate-dependent. Importantly, it is inhibited by the ketone body acetoacetate (AcAc) starting at 10 μM (maximal effect at 0.5mM). Butyrate derives from the fermentation of prebiotics, is present physiologically in the colon and is a strong producer of AcAc: indeed butyrate induces in the colon the transcription of mitochondrial 3-hydroxy-3-methyl glutarylCoA (HMGCoA) synthase, a key enzyme in ketone body synthesis. Obesity and insulin resistance were shown to be dependent on increased permeability of the colon epithelium to bacterial lipopolysaccharide (LPS); the process is evident particularly upon ingestion of lipids (a peroxidative event, inhibited by vitamin E) and is likely sensitive to AcAc. The oxidation of butyrate and the production of AcAc in the colon appear to be inhibited by high luminal sulphides and high NH3, a situation that presumably facilitates LPS permeation (on the contrary beta-hydroxy-butyrate oxidation is not inhibited). It is proposed that these damaging events may be opposed by the delivery of ketone bodies directly to the colon. PMID:23466063

  2. Synthesis of trifluoromethyl ketones as inhibitors of antennal esterases of insects.

    PubMed

    Parrilla, A; Villuendas, I; Guerrero, A

    1994-04-01

    A variety of long chain aliphatic and aromatic trifluoromethyl ketones I-XIV has been conveniently prepared, many of them for the first time, from the corresponding Grignard or organolithium derivatives. Two of them, (Z)-1,1,1-trifluoro-15-octadecen-13-yn-2-one (XV) and (Z)-1,1,1-trifluoro-16-nonadecen-14-yn-2-one (XVI), structurally-closed analogues of (Z)-13-hexadecen-11-ynyl acetate, the sex pheromone of the processionary moth Thaumetopoea pityocampa, have been stereospecifically synthesized in excellent yield by a convenient new method. The procedure involves lithiation of the corresponding iododerivative XXIX and XXX with one equivalent of tert-BuLi to obviate addition of the reagent to the enyne system. Some of the compounds have already been tested and found to be good inhibitors of antennal esterases in the Egyptian armyworm Spodoptera littoralis and the pheromone action in the processionary moth Thaumetopoea pityocampa. beta-Thiotrifluoromethyl ketones XVII-XX, which are expected to enhance the inhibition activity of the parent ketones due to their higher hydration constants, have also been prepared in good yields. PMID:7922135

  3. Studies of the condensation of sulfones with ketones and aldehydes.

    PubMed

    Garst, Michael E; Dolby, Lloyd J; Esfandiari, Shervin; Okrent, Rachel A; Avey, Alfred A

    2006-01-20

    [reaction: see text] The condensation of ketones or aldehydes with sulfones was shown to give a variety of products. Condensation of 2-methylcyclohexanone with dimethyl sulfone using potassium t-butoxide as base gave useful yields of 1,2-dimethylenecyclohexane. Under the same conditions, cycloheptanone, 3-methyl-2-butanone, and 2-butanone were converted to dienes. Remarkably, these reaction conditions converted acetophenone into p-terphenyl (10%) and (E)-1,4-diphenyl-3-penten-1-one (44%). Propiophenone was converted to 2'-methyl-p-terphenyl (61%). Using alpha-tetralone produced 1-methynaphthalene and naphthalene. No reaction took place with beta-tetralone. Using diethyl sulfone with alpha-tetralone lead to pure naphthalene. Condensation of isobutyraldehyde and dimethyl sulfone using potassium t-butoxide gave isoprene in low yield. Using benzaldehyde and benzyl phenyl sulfone in N,N-dimethylacetamide gave 1,2-diphenyl-1-phenylsulfonylethylene, N,N-dimethylcinnamide, and a complex condensation product. Only 1,2-diphenyl-1-phenylsulfonylethylene was obtained when the solvent was THF. PMID:16408963

  4. Effect of the chirality of the glycerol backbone on the bilayer and nonbilayer phase transitions in the diastereomers of di-dodecyl-beta-D-glucopyranosyl glycerol.

    PubMed Central

    Mannock, D A; Lewis, R N; McElhaney, R N; Akiyama, M; Yamada, H; Turner, D C; Gruner, S M

    1992-01-01

    We have studied the physical properties of aqueous dispersions of 1,2-sn- and 2,3-sn-didodecyl-beta-D-glucopyranosyl glycerols, as well as their diastereomeric mixture, using differential scanning calorimetry and low angle x-ray diffraction. Upon heating, both the chiral lipids and the diastereomeric mixture exhibit characteristically energetic L beta/L alpha phase transitions at 31.7-32.8 degrees C and two or three weakly energetic thermal events between 49 degrees C and 89 degrees C. In the diastereomeric mixture and the 1,2-sn glycerol derivative, these higher temperature endotherms correspond to the formation of, and interconversions between, several nonlamellar structures and have been assigned to L alpha/QIIa, QIIa/QIIb, and QIIb/HII phase transitions, respectively. The cubic phases QIIa and QIIb, whose cell lattice parameters are strongly temperature dependent, can be identified as belonging to space groups Ia3d and Pn3m/Pn3, respectively. In the equivalent 2,3-sn glucolipid, the QIIa phase is not observed and only two transitions are seen at 49 degrees C and 77 degrees C, which are identified as L alpha/QIIb and QIIb/HII phase transitions, respectively. These phase transitions temperatures are some 10 degrees C lower than those of the corresponding phase transitions observed in the diastereomeric mixture and the 1,2-sn glycerol derivative. On cooling, all three lipids exhibit a minor higher temperature exothermic event, which can be assigned to a HII/QIIb phase transition. An exothermic L alpha/L beta phase transition is observed at 30-31 degrees C. A shoulder is sometimes discernible on the high temperature side of the L alpha/L beta event, which may originate from a QIIb/L alpha phase transition prior to the freezing of the hydrocarbon chains. None of the lipids show evidence of a QIIa phase on cooling. No additional exothermic transitions are observed on further cooling to -3 degrees C. However, after nucleation at 0 degrees C followed by a short period

  5. Enzyme activities support the use of liver lipid-derived ketone bodies as aerobic fuels in muscle tissues of active sharks.

    PubMed

    Watson, R R; Dickson, K A

    2001-01-01

    Few data exist to test the hypothesis that elasmobranchs utilize ketone bodies rather than fatty acids for aerobic metabolism in muscle, especially in continuously swimming, pelagic sharks, which are expected to be more reliant on lipid fuel stores during periods between feeding bouts and due to their high aerobic metabolic rates. Therefore, to provide support for this hypothesis, biochemical indices of lipid metabolism were measured in the slow-twitch, oxidative (red) myotomal muscle, heart, and liver of several active shark species, including the endothermic shortfin mako, Isurus oxyrinchus. Tissues were assayed spectrophotometrically for indicator enzymes of fatty acid oxidation (3-hydroxy-o-acyl-CoA dehydrogenase), ketone-body catabolism (3-oxoacid-CoA transferase), and ketogenesis (hydroxy-methylglutaryl-CoA synthase). Red muscle and heart had high capacities for ketone utilization, low capacities for fatty acid oxidation, and undetectable levels of ketogenic enzymes. Liver demonstrated undetectable activities of ketone catabolic enzymes but high capacities for fatty acid oxidation and ketogenesis. Serum concentrations of the ketone beta-hydroxybutyrate varied interspecifically (means of 0.128-0.978 micromol mL(-1)) but were higher than levels previously reported for teleosts. These results are consistent with the hypothesis that aerobic metabolism in muscle tissue of active sharks utilizes ketone bodies, and not fatty acids, derived from liver lipid stores. PMID:11247746

  6. Intercalation of cyclic ketones into vanadyl phosphate

    SciTech Connect

    Zima, Vitezslav . E-mail: vitezslav.zima@upce.cz; Melanova, Klara; Benes, Ludvik; Trchova, Miroslava; Dybal, Jiri

    2005-01-15

    Intercalation compounds of vanadyl phosphate with cyclic ketones (cyclopentanone, cyclohexanone, 4-methylcyclohexanone, and 1,4-cyclohexanedione) were prepared from corresponding propanol or ethanol intercalates by a molecular exchange. The intercalates prepared were characterized using powder X-ray diffraction and thermogravimetric analysis. The intercalates are stable in dry environment and decompose slowly in humid air. Infrared and Raman spectra indicate that carbonyl oxygens of the guest molecules are coordinated to the vanadium atoms of the host layers. The local structure and interactions in the cyclopentanone intercalate have been suggested on the basis of quantum chemical calculations.

  7. Rhodium-catalyzed Asymmetric Hydrogenation of α-Dehydroamino Ketones: A General Approach to Chiral α-amino Ketones.

    PubMed

    Gao, Wenchao; Wang, Qingli; Xie, Yun; Lv, Hui; Zhang, Xumu

    2016-01-01

    Rhodium/DuanPhos-catalyzed asymmetric hydrogenation of aliphatic α-dehydroamino ketones has been achieved and afforded chiral α-amino ketones in high yields and excellent enantioselectives (up to 99 % ee), which could be reduced further to chiral β-amino alcohols by LiAlH(tBuO)3 with good yields. This protocol provides a readily accessible route for the synthesis of chiral α-amino ketones and chiral β-amino alcohols. PMID:26425824

  8. Production of methyl-vinyl ketone from levulinic acid

    DOEpatents

    Dumesic, James A.; West; Ryan M.

    2011-06-14

    A method for converting levulinic acid to methyl vinyl ketone is described. The method includes the steps of reacting an aqueous solution of levulinic acid, over an acid catalyst, at a temperature of from room temperature to about 1100 K. Methyl vinyl ketone is thereby formed.

  9. 40 CFR 721.4925 - Methyl n-butyl ketone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Methyl n-butyl ketone. 721.4925 Section 721.4925 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.4925 Methyl n-butyl ketone....

  10. 27 CFR 21.117 - Methyl isobutyl ketone.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Methyl isobutyl ketone. 21.117 Section 21.117 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS FORMULAS FOR DENATURED ALCOHOL AND RUM Specifications for Denaturants § 21.117 Methyl isobutyl ketone. (a)...

  11. 27 CFR 21.117 - Methyl isobutyl ketone.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Methyl isobutyl ketone. 21.117 Section 21.117 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL FORMULAS FOR DENATURED ALCOHOL AND RUM Specifications for Denaturants § 21.117 Methyl isobutyl ketone. (a)...

  12. 21 CFR 862.1435 - Ketones (nonquantitative) test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...) test system is a device intended to identify ketones in urine and other body fluids. Identification of... Section 862.1435 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... acidity of body fluids) or ketosis (a condition characterized by increased production of ketone...

  13. 21 CFR 862.1435 - Ketones (nonquantitative) test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...) test system is a device intended to identify ketones in urine and other body fluids. Identification of... Section 862.1435 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... acidity of body fluids) or ketosis (a condition characterized by increased production of ketone...

  14. 21 CFR 862.1435 - Ketones (nonquantitative) test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...) test system is a device intended to identify ketones in urine and other body fluids. Identification of... Section 862.1435 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... acidity of body fluids) or ketosis (a condition characterized by increased production of ketone...

  15. 21 CFR 862.1435 - Ketones (nonquantitative) test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...) test system is a device intended to identify ketones in urine and other body fluids. Identification of... Section 862.1435 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... acidity of body fluids) or ketosis (a condition characterized by increased production of ketone...

  16. 27 CFR 21.117 - Methyl isobutyl ketone.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Methyl isobutyl ketone. 21.117 Section 21.117 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS FORMULAS FOR DENATURED ALCOHOL AND RUM Specifications for Denaturants § 21.117 Methyl isobutyl ketone. (a)...

  17. 27 CFR 21.117 - Methyl isobutyl ketone.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Methyl isobutyl ketone. 21.117 Section 21.117 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL FORMULAS FOR DENATURED ALCOHOL AND RUM Specifications for Denaturants § 21.117 Methyl isobutyl ketone. (a)...

  18. IRIS TOXICOLOGICAL REVIEW OF METHYL ETHYL KETONE (2003 Final)

    EPA Science Inventory

    EPA is announcing the release of the final report, "Toxicological Review of Methyl Ethyl Ketone: in support of the Integrated Risk Information System (IRIS)". The updated Summary for Methyl Ethyl Ketone and accompanying Quickview have also been added to the IRIS Database.

  19. Decarboxylative dearomatization and mono-α-arylation of ketones.

    PubMed

    Mendis, Shehani N; Tunge, Jon A

    2016-06-01

    We report the first example of a palladium-catalyzed decarboxylative dearomatization reaction that occurs via Pd-π-benzyl intermediates. In fact, the Pd-catalyzed decarboxylative cross-coupling reaction of benzyl enol carbonates can lead to either the dearomatized alicyclic ketones or α-monoarylated ketone products depending on the catalyst and ligand employed. PMID:27229656

  20. A sulfonated poly (aryl ether ether ketone ketone) isomer: synthesis and DMFC performance

    SciTech Connect

    Kim, Yu Seung; Liu, Baijun; Hu, Wei; Jiang, Zhenhua; Robertson, Gilles; Guiver, Michael

    2009-01-01

    A sulfonated poly(aryl ether ether ketone ketone) (PEEKK) having a well-defined rigid homopolymer-like chemical structure was synthesized from a readily-prepared PEEKK post-sulfonation with concentrated sulfuric acid at room temperature within several hours. The polymer electrolyte membrane (PEM) cast from the resulting polymer exhibited an excellent combination of thermal resistance, oxidative and dimensional stability, low methanol fuel permeability and high proton conductivity. Furthermore, membrane electrode assemblies (MEAs) were successfully fabricated and good direct methanol fuel cell (DMFC) performance was observed. At 2 M MeOH feed, the current density at 0.5 V reached 165 mA/cm, which outperformed our reported analogues and eveluated Nafion membranes.

  1. Metal-Catalysed Transfer Hydrogenation of Ketones.

    PubMed

    Štefane, Bogdan; Požgan, Franc

    2016-04-01

    We highlight recent developments of catalytic transfer hydrogenation of ketones promoted by transition metals, while placing it within its historical context. Since optically active secondary alcohols are important building blocks in fine chemicals synthesis, the focus of this review is devoted to chiral catalyst types which are capable of inducing high stereoselectivities. Ruthenium complexes still represent the largest part of the catalysts, but other metals (e.g. Fe) are rapidly penetrating this field. While homogeneous transfer hydrogenation catalysts in some cases approach enzymatic performance, the interest in heterogeneous catalysts is constantly growing because of their reusability. Despite excellent activity, selectivity and compatibility of metal complexes with a variety of functional groups, no universal catalysts exist. Development of future catalyst systems is directed towards reaching as high as possible activity with low catalyst loadings, using "greener" conditions, and being able to operate under mild conditions and in a highly selective manner for a broad range of substrates. PMID:27573143

  2. Engineering of Bacterial Methyl Ketone Synthesis for Biofuels

    PubMed Central

    Goh, Ee-Been; Baidoo, Edward E. K.; Keasling, Jay D.

    2012-01-01

    We have engineered Escherichia coli to overproduce saturated and monounsaturated aliphatic methyl ketones in the C11 to C15 (diesel) range; this group of methyl ketones includes 2-undecanone and 2-tridecanone, which are of importance to the flavor and fragrance industry and also have favorable cetane numbers (as we report here). We describe specific improvements that resulted in a 700-fold enhancement in methyl ketone titer relative to that of a fatty acid-overproducing E. coli strain, including the following: (i) overproduction of β-ketoacyl coenzyme A (CoA) thioesters achieved by modification of the β-oxidation pathway (specifically, overexpression of a heterologous acyl-CoA oxidase and native FadB and chromosomal deletion of fadA) and (ii) overexpression of a native thioesterase (FadM). FadM was previously associated with oleic acid degradation, not methyl ketone synthesis, but outperformed a recently identified methyl ketone synthase (Solanum habrochaites MKS2 [ShMKS2], a thioesterase from wild tomato) in β-ketoacyl-CoA-overproducing strains tested. Whole-genome transcriptional (microarray) studies led to the discovery that FadM is a valuable catalyst for enhancing methyl ketone production. The use of a two-phase system with decane enhanced methyl ketone production by 4- to 7-fold in addition to increases from genetic modifications. PMID:22038610

  3. Point-of-Care Glucose and Ketone Monitoring.

    PubMed

    Chong, Siew Kim; Reineke, Erica L

    2016-03-01

    Early and rapid identification of hypo- and hyperglycemia as well as ketosis is essential for the practicing veterinarian as these conditions can be life threatening and require emergent treatment. Point-of-care testing for both glucose and ketone is available for clinical use and it is important for the veterinarian to understand the limitations and potential sources of error with these tests. This article discusses the devices used to monitor blood glucose including portable blood glucose meters, point-of-care blood gas analyzers and continuous glucose monitoring systems. Ketone monitoring options discussed include the nitroprusside reagent test strips and the 3-β-hydroxybutyrate ketone meter. PMID:27451045

  4. Substrate-controlled Michael additions of chiral ketones to enones.

    PubMed

    Fàbregas, Mireia; Gómez-Palomino, Alejandro; Pellicena, Miquel; Reina, Daniel F; Romea, Pedro; Urpí, Fèlix; Font-Bardia, Mercè

    2014-12-01

    Substrate-controlled Michael additions of the titanium(IV) enolate of lactate-derived ketone 1 to acyclic α,β-unsaturated ketones in the presence of a Lewis acid (TiCl4 or SnCl4) provide the corresponding 2,4-anti-4,5-anti dicarbonyl compounds in good yields and excellent diastereomeric ratios. Likely, the nucleophilic species involved in such additions are bimetallic enolates that may add to enones through cyclic transition states. Finally, further studies indicate that a structurally related β-benzyloxy chiral ketone can also participate in such stereocontrolled conjugate additions. PMID:25423031

  5. A novel alpha-arylation of ketones, aldehydes, and esters via a photoinduced SN1 reaction through 4-aminophenyl cations.

    PubMed

    Fraboni, Andrea; Fagnoni, Maurizio; Albini, Angelo

    2003-06-13

    4-Aminophenyl cations (expediently generated by photolysis of 4-chloroaniline and its N,N-dimethyl derivative by photolysis in MeCN) added to enamines and gave the corresponding alpha-(4-aminophenyl) ketones in satisfactory yields. The yields of the same ketones were increased when silyl enol ethers were used in the place of enamines. The alpha-arylation of silyl enol ethers of aldehydes occurred with lower yields and only with the N,N-dimethyl derivative. The procedure was successful with ketene silyl acetals giving in a single step a good yield of alpha-(4-aminophenyl)propionic(acetic) esters, known intermediates for the preparation of analgesic compounds. The reaction of the aryl cation with Danishefsky's diene gave the arylated beta-methoxy enone. The method is complementary to the recently developed palladium-catalyzed alpha-arylation and occurs under neutral conditions. PMID:12790595

  6. Coulometric generation of hydrogen ions by oxidation of mercury in methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone.

    PubMed

    Mihajlović, R P; Joksimović, V M; Mihajlović, Lj V

    2003-11-01

    Mercury(II)-chloride reacts with anhydrous methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone in a precise stoichiometry ratio (1:2), and weakly ionized compounds of mercury with ketones are formed and equivalent quantity of HCl is released. The application of a mercury anode for the quantitative generation of H(+) ions in 0.25 M sodium perchlorate in anhydrous methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone has been investigated. Current/potentials curves for the solvents, titrated bases, indicator and mercury showed that in these solvents mercury is oxidized at potentials much more negative than those for the titrated bases and other components present in the solution. The protons generated in this way have been used for the titration of some organic bases, with either visual or potentiometric end-point detection. The oxidation of mercury in methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone and the reaction of mercury ions with these solvents have been found to proceed with 100% current efficiency. PMID:18969192

  7. Oxidative acetoxylation of the silyl ethers of ketone enols

    SciTech Connect

    Brunovlenskaya, I.I.; Kusainova, K.M.; Kashin, A.K.

    1988-07-20

    The authors studied the reaction of (dicarboxyiodo)benzenes with the trimethylsilyl ethers of ketone enols having various structures. They also undertook a comparative investigation of the oxidation of these compounds with lead tetraacetate. The reaction of (diacetoxyiodo)benzene with the trimethylsilyl ethers of ketone enols takes place with retention of the (CH/sub 3/)/sub 3/Si group in two directions, i.e., substitution of the vinylic hydrogen or diacetoxylation of the double bond. The reaction can be used for the regioselective synthesis of /alpha/-acetoxy ketones, since the trimethylsilyl group is readily eliminated from the obtained products by the action of fluoride ion or boron trifluoride etherate with the formation of the corresponding substituted ketones.

  8. Copper/Manganese Cocatalyzed Oxidative Coupling of Vinylarenes with Ketones.

    PubMed

    Lan, Xing-Wang; Wang, Nai-Xing; Zhang, Wei; Wen, Jia-Long; Bai, Cui-Bing; Xing, Yalan; Li, Yi-He

    2015-09-18

    A novel copper/manganese cocatalyzed direct oxidative coupling of terminal vinylarenes with ketones via C(sp(3))-H bond functionalization following C-C bond formation has been developed using tert-butyl hydroperoxide as the radical initiator. Various ketones underwent a free-radical addition of terminal vinylarenes to give the corresponding 1,4-dicarbonyl products with excellent regioselectivity and efficiency through one step. A possible reaction mechanism has been proposed. PMID:26348870

  9. Rotational Spectroscopy of Methyl Vinyl Ketone

    NASA Astrophysics Data System (ADS)

    Zakharenko, Olena; Motiyenko, R. A.; Aviles Moreno, Juan-Ramon; Huet, T. R.

    2015-06-01

    Methyl vinyl ketone, MVK, along with previously studied by our team methacrolein, is a major oxidation product of isoprene, which is one of the primary contributors to annual global VOC emissions. In this talk we present the analysis of the rotational spectrum of MVK recorded at room temperature in the 50 -- 650 GHz region using the Lille spectrometer. The spectroscopic characterization of MVK ground state will be useful in the detailed analysis of high resolution infrared spectra. Our study is supported by high level quantum chemical calculations to model the structure of the two stable s-trans and s-cis conformers and to obtain the harmonic force field parameters, internal rotation barrier heights, and vibrational frequencies. In the Doppler-limited spectra the splittings due to the internal rotation of methyl group are resolved, therefore for analysis of this molecule we used the Rho-Axis-Method Hamiltonian and RAM36 code to fit the rotational transitions. At the present time the ground state of two conformers is analyzed. Also we intend to study some low lying excited states. The analysis is in progress and the latest results will be presented. Support from the French Laboratoire d'Excellence CaPPA (Chemical and Physical Properties of the Atmosphere) through contract ANR-10-LABX-0005 of the Programme d'Investissements d'Avenir is acknowledged.

  10. Studies on Crystalline Structure of Poly(aryl ether ketone ketone) Copolymer

    NASA Astrophysics Data System (ADS)

    Honigfort, P. S.; Ho, R. M.; Cheng, S. Z. D.

    1998-03-01

    Recent studies on the Poly(aryl ether ketone ketone) [PEKK(T/I)] copolymer containing alternating terphthalic acid (T) and isopthalic acid (I) linked phenylene units have left unanswered polymorphic questions. To help answer these questions a PEKK(T/I) oligomer was prepared and its crystal structure was investigated and compared to results from the copolymer. Evidence was found for 3 different crystal forms. When the copolymer is crystallized near 300 C, only one orthorhombic unit cell (form I) forms, and these crystals are also evident in the oligomer. At crystallization temperatures below 210 C, another crystal unit cell (form II) occurs which can also be isolated in the oligomer. Also, evidence for a new form (form III), which coexists with both form I and II was identified in both the copolymer and the oligomer between 200 and 280 C. Evidence of a larger supercell symmetry consisting of 3 unit cells staggered in the a-axis dimension was seen in electron diffraction studies of form III. This research was supported by WSFDMR(96-17030).

  11. The partitioning of ketones between the gas and aqueous phases

    NASA Astrophysics Data System (ADS)

    Betterton, Eric A.

    Most ketones are not significantly hydrated; they therefore retain their chromophore and they could be photolytically degraded in solution yielding a variety of products including carboxylic acids, aldehydes and radicals. It is difficult to accurately model the partitioning of ketones between the gas phase and aqueous phase because of the lack suitable estimates of the Henry's Law constants; consequently the fate and environmental effects of ketones cannot be confidently predicted. Here we report the experimental determination of the Henry's Law constants of a series of ketones that has yielded a simple straight line equation to predict the Henry's Law constants of simple aliphatic ketones: log H ∗ =0.23Σσ ∗ + 1.51; where H ∗ is the effective Henry's Law constant (M atm -1, and Σσ ∗ is the Taft polar substituents constants. The results for 25°C are (M atm -1) CH 3COCH 3, 32; C 6H 5COCH 3, 110; CH 2ClCOCH 3, 59; CH 3COCOCH 3, 74; CF 3COCH 3, 138. Acetophenone appears to have an abnormally high H ∗. Most low molecular weight aliphatic ketones are predicted to characterized by H ∗⩾30 M atm -1 and therefore they are expected to be found in the aqueous phase at concentrations of ⩾5 - 0.5 μM (given a typical gas-phase concentration range of 1-10 ppbv). The expected rate of decomposition of ketones due to photolysis in hydrometers is briefly discussed.

  12. Water chemical ionization mass spectrometry of aldehydes, ketones esters, and carboxylic acids

    SciTech Connect

    Hawthorne, S.B.; Miller, D.J.

    1986-11-01

    Chemical ionization mass spectrometry (CI) of aliphatic and aromatic carbonyl compounds using water as the reagent gas provides intense pseudomolecular ions and class-specific fragmentation patterns that can be used to identify aliphatic aldehydes, ketones, carboxylic acids, and esters. The length of ester acyl and alkyl groups can easily be determined on the basis of loss of alcohols from the protonated parent. Water CI provides for an approximately 200:1 selectivity of carbonyl species over alkanes. No reagent ions are detected above 55 amu, allowing species as small as acetone, propanal, acetic acid, and methyl formate to be identified. When deuterate water was used as the reagent, only the carboxylic acids and ..beta..-diketones showed significant H/D exchange. The use of water CI to identify carbonyl compounds in a wastewater from the supercritical water extraction of lignite coal, in lemon oil, and in whiskey volatiles is discussed.

  13. Luminescent single-ion magnets from Lanthanoid(III) complexes with monodentate ketone ligands

    NASA Astrophysics Data System (ADS)

    Kanetomo, Takuya; Ishida, Takayuki

    2016-02-01

    We synthesized [LnIII(hfac)3(H2O)(L)] (abbreviated as Ln-L; Ln = Gd, Tb, Eu; L = DTBK (di-t-butyl ketone), BP (benzophenone)), in which the carbonyl oxygen atom was coordinated to the Ln ion center, despite of such bulky substituents. Their crystal structures were determined by means of X-ray diffraction study. Gd-DTBK is completely isomorphous to the di-t-butyl nitroxide derivative and accordingly can be regarded as a model with the ligand spin masked. The ac magnetic susceptibility measurements on Tb-DTBK and -BP showed frequency dependence, characteristic of single-ion magnets. They also displayed photoluminescence in the solid state at room temperature. The quantum yields of the luminescence of Tb-DTBK and -BP (λex = 360 nm) were improved to 57 and 35%, respectively, from that of the starting material [TbIIII(hfac)3(H2O)2] (28% at λex = 370 nm). Similarly, the quantum yields for Eu-DTBK and -BP were 8 and 15%, respectively, with λex = 400 nm, while that of the starting material [EuIIII(hfac)3(H2O)2] was 4% at λex=400 nm.

  14. Cerebral metabolic adaptation and ketone metabolism after brain injury

    PubMed Central

    Prins, Mayumi L

    2010-01-01

    The developing central nervous system has the capacity to metabolize ketone bodies. It was once accepted that on weaning, the ‘post-weaned/adult’ brain was limited solely to glucose metabolism. However, increasing evidence from conditions of inadequate glucose availability or increased energy demands has shown that the adult brain is not static in its fuel options. The objective of this review is to summarize the body of literature specifically regarding cerebral ketone metabolism at different ages, under conditions of starvation and after various pathologic conditions. The evidence presented supports the following findings: (1) there is an inverse relationship between age and the brain’s capacity for ketone metabolism that continues well after weaning; (2) neuroprotective potentials of ketone administration have been shown for neurodegenerative conditions, epilepsy, hypoxia/ischemia, and traumatic brain injury; and (3) there is an age-related therapeutic potential for ketone as an alternative substrate. The concept of cerebral metabolic adaptation under various physiologic and pathologic conditions is not new, but it has taken the contribution of numerous studies over many years to break the previously accepted dogma of cerebral metabolism. Our emerging understanding of cerebral metabolism is far more complex than could have been imagined. It is clear that in addition to glucose, other substrates must be considered along with fuel interactions, metabolic challenges, and cerebral maturation. PMID:17684514

  15. Stereoselective Reduction of Prochiral Ketones by Plant and Microbial Biocatalysts.

    PubMed

    Javidnia, K; Faghih-Mirzaei, E; Miri, R; Attarroshan, M; Zomorodian, K

    2016-01-01

    Chiral alcohols are the key chiral building blocks to many enantiomerically pure pharmaceuticals. The biocatalytic approach in asymmetric reduction of corresponding prochiral ketones to the preparation of these optically pure substances is one of the most promising routes. The stereoselective reduction of different kinds of prochiral ketones catalyzed by various plants and microorganisms was studied in this work. Benzyl acetoacetate, methyl 3-oxopentanoate, ethyl 3-oxopentanoate, and ethyl butyryl acetate were chosen as the model substrates for β-ketoesters. Benzoyl acetonitrile, 3-chloro propiophenone, and 1-acetyl naphthalene were chosen as aromatic aliphatic ketones. Finally, 2-methyl benzophenone and 4-chloro benzophenone were selected as diaryl ketones. Plant catalysis was conducted by Daucus carota, Brassica rapa, Brassica oleracea, Pastinaca sativa, and Raphnus sativus. For microbial catalysis, Aspergillus foetidus, Penicillum citrinum, Saccharomyces carlbergensis, Pichia fermentans, and Rhodotrula glutinis were chosen. Chiral alcohols were obtained in high yields and with optical purity. A superiority in the microorganisms' performance in the bioreduction of prochiral ketones was detected. Among microorganisms, Rhodotrula glutinis showed remarkable results with nearly all substrates and is proposed for future studies. PMID:27168684

  16. Stereoselective Reduction of Prochiral Ketones by Plant and Microbial Biocatalysts

    PubMed Central

    Javidnia, K.; Faghih-Mirzaei, E.; Miri, R.; Attarroshan, M.; Zomorodian, K.

    2016-01-01

    Chiral alcohols are the key chiral building blocks to many enantiomerically pure pharmaceuticals. The biocatalytic approach in asymmetric reduction of corresponding prochiral ketones to the preparation of these optically pure substances is one of the most promising routes. The stereoselective reduction of different kinds of prochiral ketones catalyzed by various plants and microorganisms was studied in this work. Benzyl acetoacetate, methyl 3-oxopentanoate, ethyl 3-oxopentanoate, and ethyl butyryl acetate were chosen as the model substrates for β-ketoesters. Benzoyl acetonitrile, 3-chloro propiophenone, and 1-acetyl naphthalene were chosen as aromatic aliphatic ketones. Finally, 2-methyl benzophenone and 4-chloro benzophenone were selected as diaryl ketones. Plant catalysis was conducted by Daucus carota, Brassica rapa, Brassica oleracea, Pastinaca sativa, and Raphnus sativus. For microbial catalysis, Aspergillus foetidus, Penicillum citrinum, Saccharomyces carlbergensis, Pichia fermentans, and Rhodotrula glutinis were chosen. Chiral alcohols were obtained in high yields and with optical purity. A superiority in the microorganisms' performance in the bioreduction of prochiral ketones was detected. Among microorganisms, Rhodotrula glutinis showed remarkable results with nearly all substrates and is proposed for future studies. PMID:27168684

  17. Enhancement of L-3-hydroxybutyryl-CoA dehydrogenase activity and circulating ketone body levels by pantethine. Relevance to dopaminergic injury

    PubMed Central

    2010-01-01

    Background The administration of the ketone bodies hydroxybutyrate and acetoacetate is known to exert a protective effect against metabolic disorders associated with cerebral pathologies. This suggests that the enhancement of their endogenous production might be a rational therapeutic approach. Ketone bodies are generated by fatty acid beta-oxidation, a process involving a mitochondrial oxido-reductase superfamily, with fatty acid-CoA thioesters as substrates. In this report, emphasis is on the penultimate step of the process, i.e. L-3-hydroxybutyryl-CoA dehydrogenase activity. We determined changes in enzyme activity and in circulating ketone body levels in the MPTP mouse model of Parkinson's disease. Since the active moiety of CoA is pantetheine, mice were treated with pantethine, its naturally-occurring form. Pantethine has the advantage of being known as an anti-inflammatory and hypolipidemic agent with very few side effects. Results We found that dehydrogenase activity and circulating ketone body levels were drastically reduced by the neurotoxin MPTP, whereas treatment with pantethine overcame these adverse effects. Pantethine prevented dopaminergic neuron loss and motility disorders. In vivo and in vitro experiments showed that the protection was associated with enhancement of glutathione (GSH) production as well as restoration of respiratory chain complex I activity and mitochondrial ATP levels. Remarkably, pantethine treatment boosted the circulating ketone body levels in MPTP-intoxicated mice, but not in normal animals. Conclusions These finding demonstrate the feasibility of the enhancement of endogenous ketone body production and provide a promising therapeutic approach to Parkinson's disease as well as, conceivably, to other neurodegenerative disorders. PMID:20416081

  18. Obligate Role for Ketone Body Oxidation in Neonatal Metabolic Homeostasis*

    PubMed Central

    Cotter, David G.; d'Avignon, D. André; Wentz, Anna E.; Weber, Mary L.; Crawford, Peter A.

    2011-01-01

    To compensate for the energetic deficit elicited by reduced carbohydrate intake, mammals convert energy stored in ketone bodies to high energy phosphates. Ketone bodies provide fuel particularly to brain, heart, and skeletal muscle in states that include starvation, adherence to low carbohydrate diets, and the neonatal period. Here, we use novel Oxct1−/− mice, which lack the ketolytic enzyme succinyl-CoA:3-oxo-acid CoA-transferase (SCOT), to demonstrate that ketone body oxidation is required for postnatal survival in mice. Although Oxct1−/− mice exhibit normal prenatal development, all develop ketoacidosis, hypoglycemia, and reduced plasma lactate concentrations within the first 48 h of birth. In vivo oxidation of 13C-labeled β-hydroxybutyrate in neonatal Oxct1−/− mice, measured using NMR, reveals intact oxidation to acetoacetate but no contribution of ketone bodies to the tricarboxylic acid cycle. Accumulation of acetoacetate yields a markedly reduced β-hydroxybutyrate:acetoacetate ratio of 1:3, compared with 3:1 in Oxct1+ littermates. Frequent exogenous glucose administration to actively suckling Oxct1−/− mice delayed, but could not prevent, lethality. Brains of newborn SCOT-deficient mice demonstrate evidence of adaptive energy acquisition, with increased phosphorylation of AMP-activated protein kinase α, increased autophagy, and 2.4-fold increased in vivo oxidative metabolism of [13C]glucose. Furthermore, [13C]lactate oxidation is increased 1.7-fold in skeletal muscle of Oxct1−/− mice but not in brain. These results indicate the critical metabolic roles of ketone bodies in neonatal metabolism and suggest that distinct tissues exhibit specific metabolic responses to loss of ketone body oxidation. PMID:21209089

  19. METHYL KETONE METABOLISM IN HYDROCARBON-UTILIZING MYCOBACTERIA

    PubMed Central

    Lukins, H. B.; Foster, J. W.

    1963-01-01

    Lukins, H. B. (University of Texas, Austin) and J. W. Foster. Methyl ketone metabolism in hydrocarbon-utilizing mycobacteria. J. Bacteriol. 85: 1074–1087. 1963.—Species of Mycobacterium especially M. smegmatis 422, produced the homologous methyl ketones during the oxidation of propane, n-butane, n-pentane, or n-hexane. A carrier-trapping experiment demonstrated the formation of 2-undecanone, as well as 1,11-undecanedioic acid, during the oxidation of undecane-1-C14. Aliphatic alkane-utilizing mycobacteria were able to grow at the expense of several aliphatic methyl ketones as sole sources of carbon. Other ketones which did not support growth were oxidized by resting bacterial suspensions. M. smegmatis 422 cells grown on propane or acetone were simultaneously adapted to oxidize both substrates, as well as n-propanol. n-Propanol cells were unadapted to propane or acetone. Acetone produced from propane in a medium enriched in D2O contained a negligible quantity of D, presumably eliminating propylene as an intermediate in the oxidation. Cells grown at the expense of alkanes or methyl ketones in the presence of O218 had a higher content of O18 than did cells grown on terminally oxidized compounds, e.g., primary alcohols or fatty acids. An oxygenase reaction is postulated for the attack on methyl ketones. Acetol was isolated and characterized as an oxidation product of acetone by M. smegmatis 422. Acetol-grown cells had a higher O18 content than did n-propanol cells, and its utilization appears to involve at least one oxygenase reaction. Acetol produced from acetone in the presence of O218 was not enriched in the isotope, indicating the occurrence of exchange reactions or of oxygenation reactions at a later stage in the assimilation of acetone and acetol. PMID:14043998

  20. Catalytic Intramolecular Ketone Alkylation with Olefins by Dual Activation.

    PubMed

    Lim, Hee Nam; Dong, Guangbin

    2015-12-01

    Two complementary methods for catalytic intramolecular ketone alkylation reactions with unactivated olefins, resulting in Conia-ene-type reactions, are reported. The transformations are enabled by dual activation of both the ketone and the olefin and are atom-economical as stoichiometric oxidants or reductants are not required. Assisted by Kool's aniline catalyst, the reaction conditions can be both pH- and redox-neutral. A broad range of functional groups are thus tolerated. Whereas the rhodium catalysts are effective for the formation of five-membered rings, a ruthenium-based system that affords the six-membered ring products was also developed. PMID:26486569

  1. Asymmetric reduction of ketones with recombinant E. coli whole cells in neat substrates.

    PubMed

    Jakoblinnert, Andre; Mladenov, Radoslav; Paul, Albert; Sibilla, Fabrizio; Schwaneberg, Ulrich; Ansorge-Schumacher, Marion B; de María, Pablo Domínguez

    2011-11-28

    The asymmetric reduction of ketones is performed by using lyophilized whole cells in neat substrates with defined water activity (a(w)). Ketones and alcohols prone to be unstable in aqueous media can now be converted via biocatalysis. PMID:22005469

  2. Utility of ketone measurement in the prevention, diagnosis and management of diabetic ketoacidosis.

    PubMed

    Misra, S; Oliver, N S

    2015-01-01

    Ketone measurement is advocated for the diagnosis of diabetic ketoacidosis and assessment of its severity. Assessing the evidence base for ketone measurement in clinical practice is challenging because multiple methods are available but there is a lack of consensus about which is preferable. Evaluating the utility of ketone measurement is additionally problematic because of variability in the biochemical definition of ketoacidosis internationally and in the proposed thresholds for ketone measures. This has led to conflicting guidance from expert bodies on how ketone measurement should be used in the management of ketoacidosis. The development of point-of-care devices that can reliably measure the capillary blood ketone β-hydroxybutyrate (BOHB) has widened the spectrum of applications of ketone measurement, but whether the evidence base supporting these applications is robust enough to warrant their incorporation into routine clinical practice remains unclear. The imprecision of capillary blood ketone measures at higher values, the lack of availability of routine laboratory-based assays for BOHB and the continued cost-effectiveness of urine ketone assessment prompt further discussion on the role of capillary blood ketone assessment in ketoacidosis. In the present article, we review the various existing methods of ketone measurement, the precision of capillary blood ketone as compared with other measures, its diagnostic accuracy in predicting ketoacidosis and other clinical applications including prevention, assessment of severity and resolution of ketoacidosis. PMID:25307274

  3. Crystal morphology and phase identifications in poly(aryl ether ketones)s and their copolymers

    SciTech Connect

    Ho, R.M.; Cheng, S.Z.D.; Hsiao, B.S.

    1995-12-01

    A series of poly(aryl ether ketone ketone)s prepared from diphenyl ether (DPE) and terephthalic acid M or isophthalic acid (T) have been investigated. PEKK(T) has been reported to exhibit two polymorphism (form I and form II) based on wide angle X-ray diffraction (WAXD) and electron diffraction (ED) experiments.

  4. 21 CFR 862.1435 - Ketones (nonquantitative) test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ketones (nonquantitative) test system. 862.1435 Section 862.1435 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry...

  5. ANALYSIS OF ALDEHYDES AND KETONES IN THE GAS PHASE

    EPA Science Inventory

    The development and testing of a 2,4-dinitrophenylhydrazine-acetonitrile (DNPH-ACN) method for the analysis of aldehydes and ketones in ambient air are described. A discussion of interferences, preparation of calibration standards, analytical testing, fluorescence methods and car...

  6. Ketonization of Cuphea oil for the production of 2-undecanone

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this work was to demonstrate the viability of the cross ketonization reaction with the triacylglycerol from Cuphea sp. and acetic acid in a fixed-bed plug-flow reactor. The seed oil from Cuphea sp. contains up to 71% decanoic acid and the reaction of this fatty acid residue with ac...

  7. Ketone body therapy: from the ketogenic diet to the oral administration of ketone ester

    PubMed Central

    Hashim, Sami A.; VanItallie, Theodore B.

    2014-01-01

    Ketone bodies (KBs), acetoacetate and β-hydroxybutyrate (βHB), were considered harmful metabolic by-products when discovered in the mid-19th century in the urine of patients with diabetic ketoacidosis. It took physicians many years to realize that KBs are normal metabolites synthesized by the liver and exported into the systemic circulation to serve as an energy source for most extrahepatic tissues. Studies have shown that the brain (which normally uses glucose for energy) can readily utilize KBs as an alternative fuel. Even when there is diminished glucose utilization in cognition-critical brain areas, as may occur early in Alzheimer’s disease (AD), there is preliminary evidence that these same areas remain capable of metabolizing KBs. Because the ketogenic diet (KD) is difficult to prepare and follow, and effectiveness of KB treatment in certain patients may be enhanced by raising plasma KB levels to ≥2 mM, KB esters, such as 1,3-butanediol monoester of βHB and glyceryl-tris-3-hydroxybutyrate, have been devised. When administered orally in controlled dosages, these esters can produce plasma KB levels comparable to those achieved by the most rigorous KD, thus providing a safe, convenient, and versatile new approach to the study and potential treatment of a variety of diseases, including epilepsy, AD, and Parkinson’s disease. PMID:24598140

  8. Ketone body therapy: from the ketogenic diet to the oral administration of ketone ester.

    PubMed

    Hashim, Sami A; VanItallie, Theodore B

    2014-09-01

    Ketone bodies (KBs), acetoacetate and β-hydroxybutyrate (βHB), were considered harmful metabolic by-products when discovered in the mid-19th century in the urine of patients with diabetic ketoacidosis. It took physicians many years to realize that KBs are normal metabolites synthesized by the liver and exported into the systemic circulation to serve as an energy source for most extrahepatic tissues. Studies have shown that the brain (which normally uses glucose for energy) can readily utilize KBs as an alternative fuel. Even when there is diminished glucose utilization in cognition-critical brain areas, as may occur early in Alzheimer's disease (AD), there is preliminary evidence that these same areas remain capable of metabolizing KBs. Because the ketogenic diet (KD) is difficult to prepare and follow, and effectiveness of KB treatment in certain patients may be enhanced by raising plasma KB levels to ≥2 mM, KB esters, such as 1,3-butanediol monoester of βHB and glyceryl-tris-3-hydroxybutyrate, have been devised. When administered orally in controlled dosages, these esters can produce plasma KB levels comparable to those achieved by the most rigorous KD, thus providing a safe, convenient, and versatile new approach to the study and potential treatment of a variety of diseases, including epilepsy, AD, and Parkinson's disease. PMID:24598140

  9. Sulphur and oxygen sequestration of n-C37 and n-C38 unsaturated ketones in an immature kerogen and the release of their carbon skeletons during early stages of thermal maturation

    USGS Publications Warehouse

    Koopmans, M.P.; Schaeffer-Reiss, C.; De Leeuw, J. W.; Lewan, M.D.; Maxwell, J.R.; Schaeffer, P.; Sinninghe, Damste J.S.

    1997-01-01

    Sedimentary rock from the Gessoso-solfifera Formation (Messinian) in the Vena del Gesso Basin (northern Italy) containing immature (Ro = 0.25%) S-rich organic matter was artificially matured by hydrous pyrolysis at temperatures from 160 to 330??C for 72 h to study the diagenetic fate of n-C37 and n-C38 di-and tri-unsaturated methyl and ethyl ketones (alkenones) biosynthesised by several prymnesiophyte algae. During early diagenesis, the alkenones are incorporated into the kerogen by both sulphur and oxygen cross-linking as indicated by chemical degradation experiments with the kerogen of the unheated sample. Heating at temperatures between 160 and 260??C, which still represents early stages of thermal maturation, produces large amounts (up to 1 mg/g TOC) of S-bound, O-bound, and both S-and O-bound n-C37 and n-C38 skeletons, saturated n-C37 and n-C38 methyl, ethyl, and mid-chain ketones, C37 and C38 mid-chain 2,5-di-n-alkylthiophenes, C37 and C38 1,2-di-n-alkylbenzenes, and C37 and C38 n-alkanes. With increasing thermal maturation, three forms of the n-C37 and n-C38 skeletons are relatively stable (saturated hydrocarbons, 1,2-di-n-alkylbenzenes and saturated ketones), whereas the S-and O-bound skeletons are relatively labile. These results suggest that in natural situations saturated ketones with an n-C37 and n-C38 skeleton can be expected as well as the corresponding hydrocarbons. Copyright ?? 1997 Elsevier Science Ltd.

  10. Measuring beta-cell function relative to insulin sensitivity in youth: Does the hyperglycemic clamp suffice?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To compare beta-cell function relative to insulin sensitivity, disposition index (DI), calculated from two clamps (2cDI, insulin sensitivity from the hyperinsulinemic-euglycemic clamp and first-phase insulin from the hyperglycemic clamp) with the DI calculated from the hyperglycemic clamp alone (hcD...

  11. Investigation of crystalline morphology in poly (ether ether ketone) using dielectric relaxation spectroscopy

    SciTech Connect

    Kalika, D.S.; Krishnaswamy, R.K.

    1993-12-31

    The relaxation behavior of poly (ether ether ketone) [PEEK] has been investigated using dielectric relaxation spectroscopy; the glass-rubber ({alpha}) relaxation and a sub-glass ({beta}) relaxation were examined for the amorphous material and both cold-crystallized and melt-crystallized specimens. Analysis of the data using the Cole-Cole modification of the Debye equation allowed determination of the dielectric relaxation strength and relaxation broadening parameter for both transitions as a function of material crystallization history. The crystallized specimens displayed a positive offset in isochronal loss temperature for both the {alpha} and {beta} relaxations, with the {alpha} relaxation broadened significantly. The measured dipolar response was interpreted using a three-phase morphological model encompassing a crystalline phase, a mobile amorphous phase, and a rigid amorphous phase. Determination of phase fractions based on dipolar mobilization across the glass-rubber relaxation revealed a finite rigid amorphous phase fraction for both the cold-crystallized specimens which was relatively insensitive to thermal history and degree of crystallinity (W{sub RAP}40.20).

  12. Beta experiment

    NASA Technical Reports Server (NTRS)

    1982-01-01

    A focused laser doppler velocimeter (LDV) system was developed for the measurement of atmospheric backscatter (beta) from aerosols at infrared wavelengths. A Doppler signal generator was used in mapping the coherent sensitive focal volume of a focused LDV system. System calibration data was analyzed during the flight test activity scheduled for the Beta system. These analyses were performed to determine the acceptability of the Beta measurement system's performance.

  13. Adsorption of di-2-pyridyl ketone salicyloylhydrazone on silica gel: characteristics and isotherms.

    PubMed

    Antonio, P; Iha, K; Suárez-Iha, M E V

    2004-10-01

    The adsorption of DPKSH onto silica gel was investigated, at 25+/-1 degrees C and pH 1, 4.7 and 12. For the same DPKSH concentration interval, the minimum required time of contact for adsorption maximum at pH 4.7 was smaller than at pH 1 and the maximum amount of DPKSH adsorbed per gram of silica at pH 1 is smaller than at pH 4.7. At pH 12 the DPKSH adsorption onto silica gel was not significant. The adsorption data followed Langmuir, Freundlich and Dubinin-Radushkevich (D-R) isotherms. The maximum amount of solute adsorbed (m(ads)(max)) and the adsorption constant, K(L), were derived from Langmuir isotherm. The Freundlich constants 1/n and K(F) related, respectively, to the energetic heterogeneity of adsorption sites and an empirical constant were evaluated. The mean sorption free energy (E) of DPKSH adsorption onto silica gel was calculated from D-R isotherm indicating a physical adsorption mode. Finally, conductimetric titrations showed the silica particle basicity and acidity as 0.002 and 0.3mmolg(-1), respectively. PMID:18969629

  14. Spectroscopic and electrochemical properties of di-2-pyridyl ketone thiosemicarbazone [dpktsc] in non-aqueous media

    NASA Astrophysics Data System (ADS)

    Bakir, Mohammed; Brown, Ordel

    2011-12-01

    Spectroscopic measurements on non-aqueous solutions of [dpktsc] divulged high sensitivity of [dpktsc] to its surroundings. 1H NMR studies performed on d 6-dmso and d 6-acetone solutions of [dpktsc] disclosed inter-molecular hydrogen bond between the amine proton and the solvent oxygen atom. In non-protophilic solvent (CDCl 3), intra-molecular hydrogen bond between the amide proton and a nitrogen atom of a pyridine ring was elucidated. Electronic absorption measurements done on non-aqueous solutions of [dpktsc] revealed two intra-ligand charge transfer transitions (ILCT) due to n → π * and π → π * of the thione followed by thione to pyridine charge transfer. In protophilic solvents, a shoulder appeared at ˜400 nm along with the ILCT transitions. Spectrophotometric titrations of [dpktsc] with NaBX 4 (X = H or F) and thermo-optical measurements in dmf disclosed that deprotonation of [dpktsc] is not favorable. When stoichiometric amounts of [MCl 2] (M = Zn, Cd or Hg) were added to dmf solutions of [dpktsc], facile conversion of [dpktsc] to its conjugate base [dpktsc-H] - and in situ formation of [MCl 2(κ 3-N,N,S-dpktsc-H] - was observed. Dmf solutions of [dpktsc] are able to detect and determine [MCl 2] in concentrations as low as 1.00 × 10 -12 M. Protophilic solutions (dmf) of [dpktsc] show high affinity to [ZnCl 2], compared to [MCl 2] (M = Cd or Hg). Electrochemical measurements done on dmf solutions of [dpktsc] in the presence and absence of [MCl 2] show reductive decomposition of [dpktsc] in the absence of [MCl 2] and in the presence of [MCl 2] electrochemical signatures consistent with the in situ formation of [MCl 2(κ 3-N,N,S-dpktsc-H)] - were observed.

  15. Novel sulfonated poly(ether ether ketone ketone)s for direct methanol fuel cells usage: Synthesis, water uptake, methanol diffusion coefficient and proton conductivity

    NASA Astrophysics Data System (ADS)

    Zhang, Gang; Fu, Tiezhu; Shao, Ke; Li, Xianfeng; Zhao, Chengji; Na, Hui; Zhang, Hong

    A novel series of sulfonated poly(ether ether ketone ketone)s (SPEEKKs) with different degrees of sulfonation (Ds) were synthesized from 1,3-bis(3-sodium sulfonate-4-fluorobenzoyl)benzene (1,3-SFBB-Na), 1,3-bis(4-fluorobenzoyl)benzene (1,3-FBB) and 3,3‧,5,5‧-tetramethyl-4,4‧-biphenol (TMBP) by aromatic nucleophilic polycondensation. The chemical structures of SPEEKKs were confirmed by FT-IR spectroscopy and the Ds values of the polymers were calculated by 1H NMR and titration methods, respectively. The thermal stabilities of the SPEEKKs in acid and sodium forms were characterized by thermogravimetric analysis (TGA), which showed that SPEEKKs had excellent thermal properties at high temperatures. All the SPEEKK polymers were easily solution cast into tough membranes. Water uptakes, proton conductivities and methanol diffusion coefficients of the SPEEKK membranes were measured. Water uptake increased with Ds and temperature. Compared to Nafion, the SPEEKK-60, -70 and -80 membranes showed higher proton conductivities at 80 °C, while the other SPEEKK membranes showed relatively lower proton conductivities. This may be due to the different distribution of ion-conducting domains in membrane. However, these membranes showed lower methanol diffusions in the range of 8.32 × 10 -9 to 1.14 × 10 -7 cm 2 s -1 compared with that of Nafion (2 × 10 -6 cm 2 s -1) at the same temperature. The membranes also showed excellent mechanical properties (with a Young's modulus > 1 GPa and a tensile strength > 40 MPa). These results indicate that the SPEEKK membranes are promising materials for use in direct methanol fuel cell (DMFC) applications.

  16. Functionalization of poly(aryl ether ether ketone)

    SciTech Connect

    Wang, Fei; Roovers, J.

    1993-12-31

    Bromomethyl and dibromomethyl substituted poly(aryl ether ether ketone) have been prepared from methyl poly(aryl ether ether ketone) by bromination with bromine. These brominated polymers are intermediates that can be further functionalized by: hydrolysis, oxidation, substitution etc. A series of new functionalized PEEK polymers has been prepared. The functional group includes -CH{sub 2}OH, -CH{sub 2}OCH{sub 3}, -CHO, -COOH, -COOCH{sub 3}, -CH{sub 2}CN, -CH{sub 2}COOH, -CH{sub 2}OCOCH{sub 3}, -CH{sub 2}N{sup +}H(CH{sub 2}CH{sub 3}){sub 2}Br{sup {minus}}, -CH{sub 2}N(CH{sub 2}CH{sub 3}){sub 2}, -CH{sub 2}N{sup +}H(CH{sub 2}CH{sub 3}){sub 3}Br{sup {minus}}.

  17. Metabolic reprogramming induced by ketone bodies diminishes pancreatic cancer cachexia

    PubMed Central

    2014-01-01

    Background Aberrant energy metabolism is a hallmark of cancer. To fulfill the increased energy requirements, tumor cells secrete cytokines/factors inducing muscle and fat degradation in cancer patients, a condition known as cancer cachexia. It accounts for nearly 20% of all cancer-related deaths. However, the mechanistic basis of cancer cachexia and therapies targeting cancer cachexia thus far remain elusive. A ketogenic diet, a high-fat and low-carbohydrate diet that elevates circulating levels of ketone bodies (i.e., acetoacetate, β-hydroxybutyrate, and acetone), serves as an alternative energy source. It has also been proposed that a ketogenic diet leads to systemic metabolic changes. Keeping in view the significant role of metabolic alterations in cancer, we hypothesized that a ketogenic diet may diminish glycolytic flux in tumor cells to alleviate cachexia syndrome and, hence, may provide an efficient therapeutic strategy. Results We observed reduced glycolytic flux in tumor cells upon treatment with ketone bodies. Ketone bodies also diminished glutamine uptake, overall ATP content, and survival in multiple pancreatic cancer cell lines, while inducing apoptosis. A decrease in levels of c-Myc, a metabolic master regulator, and its recruitment on glycolytic gene promoters, was in part responsible for the metabolic phenotype in tumor cells. Ketone body-induced intracellular metabolomic reprogramming in pancreatic cancer cells also leads to a significantly diminished cachexia in cell line models. Our mouse orthotopic xenograft models further confirmed the effect of a ketogenic diet in diminishing tumor growth and cachexia. Conclusions Thus, our studies demonstrate that the cachectic phenotype is in part due to metabolic alterations in tumor cells, which can be reverted by a ketogenic diet, causing reduced tumor growth and inhibition of muscle and body weight loss. PMID:25228990

  18. A constitutive model of polyether-ether-ketone (PEEK).

    PubMed

    Chen, Fei; Ou, Hengan; Lu, Bin; Long, Hui

    2016-01-01

    A modified Johnson-Cook (JC) model was proposed to describe the flow behaviour of polyether-ether-ketone (PEEK) with the consideration of coupled effects of strain, strain rate and temperature. As compared to traditional JC model, the modified one has better ability to predict the flow behaviour at elevated temperature conditions. In particular, the yield stress was found to be inversely proportional to temperature from the predictions of the proposed model. PMID:26409233

  19. Catalytic Leuckart-Wallach-type reductive amination of ketones.

    PubMed

    Kitamura, Masato; Lee, Donghyun; Hayashi, Shinnosuke; Tanaka, Shinji; Yoshimura, Masahiro

    2002-11-29

    A CpRh(III) complex catalyzes reductive amination of ketones using HCOONH(4) at 50-70 degrees C to give the corresponding primary amines in high yields. The reaction is clean and operationally simple and proceeds at a lower temperature and with higher chemoselectivity than the original Leuckart-Wallach reaction. The new method has been applied to the synthesis of alpha-amino acids directly from alpha-keto acids. PMID:12444661

  20. Solvation of Esters and Ketones in Supercritical CO2.

    PubMed

    Kajiya, Daisuke; Imanishi, Masayoshi; Saitow, Ken-ichi

    2016-02-01

    Vibrational Raman spectra for the C═O stretching modes of three esters with different functional groups (methyl, a single phenyl, and two phenyl groups) were measured in supercritical carbon dioxide (scCO2). The results were compared with Raman spectra for three ketones involving the same functional groups, measured at the same thermodynamic states in scCO2. The peak frequencies of the Raman spectra of these six solute molecules were analyzed by decomposition into the attractive and repulsive energy components, based on the perturbed hard-sphere theory. For all solute molecules, the attractive energy is greater than the repulsive energy. In particular, a significant difference in the attractive energies of the ester-CO2 and ketone-CO2 systems was observed when the methyl group is attached to the ester or ketone. This difference was significantly reduced in the solute systems with a single phenyl group and was completely absent in those with two phenyl groups. The optimized structures among the solutes and CO2 molecules based on quantum chemical calculations indicate that greater attractive energy is obtained for a system where the oxygen atom of the ester is solvated by CO2 molecules. PMID:26741296

  1. Me2(CH2Cl)SiCN: Bifunctional Cyanating Reagent for the Synthesis of Tertiary Alcohols with a Chloromethyl Ketone Moiety via Ketone Cyanosilylation.

    PubMed

    Zeng, Xing-Ping; Zhou, Jian

    2016-07-20

    We report a novel bifunctional cyanating reagent, Me2(CH2Cl)SiCN, which paves the way to a one-pot sequential synthesis of tertiary alcohols featuring a chloromethyl ketone moiety via enantioselective ketone cyanosilylation. This method contributes to gram-scale enantioselective total synthesis of the aggregation pheromone of the Colorado potato beetle, (S)-CPB. PMID:27399262

  2. New compatible solutes related to Di-myo-inositol-phosphate in members of the order Thermotogales.

    PubMed Central

    Martins, L O; Carreto, L S; Da Costa, M S; Santos, H

    1996-01-01

    The accumulation of intracellular organic solutes was examined in six species of the order Thermotogales by nuclear magnetic resonance spectroscopy. The newly discovered compounds di-2-O-beta-mannosyl-di-myo-inositol-1,1'(3,3')-phosphate and di-myo-inositol-1,3'-phosphate were identified in Thermotoga maritima and Thermotoga neapolitana. In the latter species, at the optimum temperature and salinity the organic solute pool was composed of di-myo-inositol-1,1'(3,3')-phosphate, beta-glutamate, and alpha-glutamate in addition to di-myo-inositol-1,3'-phosphate and di-2-O-beta-mannosyl-di-myo-inositol-1,1'(3,3')-phosphate. The concentrations of the last two solutes increased dramatically at supraoptimal growth temperatures, whereas beta-glutamate increased mainly in response to a salinity stress. Nevertheless, di-myo-inositol-1,1'(3,3')-phosphate was the major compatible solute at salinities above the optimum for growth. The amino acids alpha-glutamate and proline were identified under optimum growth conditions in Thermosipho africanus, and beta-mannosylglycerate, trehalose, and glycine betaine were detected in Petrotoga miotherma. Organic solutes were not detected, under optimum growth conditions, in Thermotoga thermarum and Fervidobacterium islandicum, which have a low salt requirement or none. PMID:8824608

  3. Advanced selective non-invasive ketone body detection sensors based on new ionophores

    NASA Astrophysics Data System (ADS)

    Sathyapalan, A.; Sarswat, P. K.; Zhu, Y.; Free, M. L.

    2014-12-01

    New molecules and methods were examined that can be used to detect trace level ketone bodies. Diseases such as type 1 diabetes, childhood hypo-glycaemia-growth hormone deficiency, toxic inhalation, and body metabolism changes are linked with ketone bodies concentration. Here we introduce, selective ketone body detection sensors based on small, environmentally friendly organic molecules with Lewis acid additives. Density functional theory (DFT) simulation of the sensor molecules (Bromo-acetonaphthone tungstate (BANT) and acetonaphthophenyl ether propiono hydroxyl tungstate (APPHT)), indicated a fully relaxed geometry without symmetry attributes and specific coordination which enhances ketone bodies sensitivity. A portable sensing unit was made in which detection media containing ketone bodies at low concentration and new molecules show color change in visible light as well as unique irradiance during UV illumination. RGB analysis, electrochemical tests, SEM characterization, FTIR, absorbance and emission spectroscopy were also performed in order to validate the ketone sensitivity of these new molecules.

  4. Rhodium-Catalyzed Ketone Methylation Using Methanol Under Mild Conditions: Formation of α-Branched Products**

    PubMed Central

    Chan, Louis K M; Poole, Darren L; Shen, Di; Healy, Mark P; Donohoe, Timothy J

    2014-01-01

    The rhodium-catalyzed methylation of ketones has been accomplished using methanol as the methylating agent and the hydrogen-borrowing method. The sequence is notable for the relatively low temperatures that are required and for the ability of the reaction system to form α-branched products with ease. Doubly alkylated ketones can be prepared from methyl ketones and two different alcohols by using a sequential one-pot iridium- and rhodium-catalyzed process. PMID:24288297

  5. On the nature of the olefination reaction involving ditungsten hexaalkoxides and aldehydes or ketones

    SciTech Connect

    Chisholm, M.H.; Huffman, J.C.; Lucas, E.A.; Sousa, A.; Streib, W.E.

    1992-03-25

    Reductive coupling of aldehydes and ketones to olefins under the action of ditungsten hexaalkoxides was investigated. In these reactions, reductive cleavage of the aldehyde or ketone carbonyl is followed by formation of the olefinic C-C bond and breaking of the carbonyl C-O bond of the second aldehyde or ketone. Observations concerning the initial C-O bond cleavage and subsequent C-C bond formation are presented. 10 refs., 4 figs.

  6. [Pollution Characteristics of Aldehydes and Ketones Compounds in the Exhaust of Beijing Typical Restaurants].

    PubMed

    Cheng, Jing-chen; Cui, Tong; He, Wan-qing; Nie, Lei; Wang, Jun-ling; Pan, Tao

    2015-08-01

    Aldehydes and ketones compounds, as one of the components in the exhaust of restaurants, are a class of volatile organic compounds (VOCs) with strong chemical reactivity. However, there is no systematic study on aldehydes and ketones compounds in the exhaust of restaurants. To further clarify the food source emission levels of aldehydes and ketones compounds and controlling measures, to access city group catering VOCs emissions control decision-making basis, this study selected 8 Beijing restaurants with different types. The aldehydes and ketones compounds were sampled using DNPH-silica tube, and then ultra performance liquid chromatography was used for quantitative measurement. The aldehydes and ketones concentrations of reference volume condition from 8 restaurants in descending order were Roasted Duck restaurant, Chinese Style Barbecue, Home Dishes, Western Fast-food, School Canteen, Chinese Style Fast-food, Sichuan Cuisine, Huaiyang Cuisine. The results showed that the range of aldehydes and ketones compounds (C1-C9) concentrations of reference volume condition in the exhaust of restaurants was 115.47-1035.99 microg x m(-3). The composition of aldehydes and ketones compounds in the exhaust of sampled restaurants was obviously different. The percentages of C1-C3 were above 40% in the exhaust from Chinese style restaurants. Fast food might emit more C4-C9 aldehydes and ketones compounds. From the current situation of existing aldehydes and ketones compounds control, the removal efficiency of high voltage electrostatic purifiers widely used in Beijing is limited. PMID:26591999

  7. Evaluation of α,β-Unsaturated Ketones as Antileishmanial Agents

    PubMed Central

    Vasquez, Miguel A.; Iniguez, Eva; Das, Umashankar; Beverley, Stephen M.; Herrera, Linda J.; Dimmock, Jonathan R.

    2015-01-01

    In this study, we assessed the antileishmanial activity of 126 α,β-unsaturated ketones. The compounds NC901, NC884, and NC2459 showed high leishmanicidal activity for both the extracellular (50% effective concentration [EC50], 456 nM, 1,122 nM, and 20 nM, respectively) and intracellular (EC50, 1,870 nM, 937 nM, and 625 nM, respectively) forms of Leishmania major propagated in macrophages, with little or no toxicity to mammalian cells. Bioluminescent imaging of parasite replication showed that all three compounds reduced the parasite burden in the murine model, with no apparent toxicity. PMID:25801571

  8. An Iron Catalyst for Ketone Hydrogenations Under Mild Conditions

    SciTech Connect

    Bullock, R. Morris

    2007-10-01

    Casey and Guan reported a homogeneous catalyst for ketone hydrogenation that does not require a precious metal, but instead is based on iron. Excellent yields and chemoselectivity for hydrogenation are found under mild conditions (25 °C, 3 atm H2). An ionic hydrogenation mechanism allows the delivery of a proton from the OH and a hydride from the metal. RMB gratefully acknowledges funding from the Division of Chemical Sciences, Office of Basic Energy Sciences, US Department of Energy, and from a grant from the Laboratory Directed Research and Development Program. Pacific Northwest National Laboratory is operated by Battelle for the U.S. Department of Energy.

  9. Asymmetric Propargylation of Ketones using Allenylboronates Catalyzed by Chiral Biphenols

    PubMed Central

    Barnett, David S.; Schaus, Scott E.

    2011-01-01

    Chiral biphenols catalyze the enantioselective asymmetric propargylation of ketones using allenylboronates. The reaction uses 10 mol % of 3,3′-Br2-BINOL as the catalyst and allenyldioxoborolane as the nucleophile, in the absence of solvent, and under microwave irradiation to afford the homopropargylic alcohol. The reaction products are obtained in good yields (60 – 98%) and high enantiomeric ratios (3:1 – 99:1). Diastereoselective propargylations using chiral racemic allenylboronates result in good diastereoselectivities (dr > 86:14) and enantioselectivities (er > 92:8) under the catalytic conditions. PMID:21732609

  10. Asymmetric propargylation of ketones using allenylboronates catalyzed by chiral biphenols.

    PubMed

    Barnett, David S; Schaus, Scott E

    2011-08-01

    Chiral biphenols catalyze the enantioselective asymmetric propargylation of ketones using allenylboronates. The reaction uses 10 mol % of 3,3'-Br(2)-BINOL as the catalyst and allenyldioxoborolane as the nucleophile, in the absence of solvent, and under microwave irradiation to afford the homopropargylic alcohol. The reaction products are obtained in good yields (60-98%) and high enantiomeric ratios (3:1-99:1). Diastereoselective propargylations using chiral racemic allenylboronates result in good diastereoselectivities (dr >86:14) and enantioselectivities (er >92:8) under the catalytic conditions. PMID:21732609

  11. Effects of trifluoromethyl ketones on the motility of Proteus vulgaris.

    PubMed

    Wolfart, Krisztina; Molnar, Annamaria; Kawase, Masami; Motohashi, Noboru; Molnar, Joseph

    2004-09-01

    In the present study, we showed the inhibition of motility by trifluoromethyl ketone (TF) derivatives (1-8) in Proteus vulgaris (P. vulgaris) cultures. Among them, 1-(2-benzoxazoyl)-3,3,3-trifluoro-2-propanone (1) showed a much stronger inhibitory effect on the motility of P. vulgaris than other TF compounds at 10% MIC. Our results suggest the possibility of an inhibitory action of TF compounds on the proton motive forces by affecting the action of biological motor and proton efflux in the membranes, resulting in a reduction of the ratio of running and the increased number of tumbling and non-motile cells. PMID:15340240

  12. Copper-catalyzed asymmetric hydrogenation of aryl and heteroaryl ketones.

    PubMed

    Krabbe, Scott W; Hatcher, Mark A; Bowman, Roy K; Mitchell, Mark B; McClure, Michael S; Johnson, Jeffrey S

    2013-09-01

    High throughput screening enabled the development of a Cu-based catalyst system for the asymmetric hydrogenation of prochiral aryl and heteroaryl ketones that operates at H2 pressures as low as 5 bar. A ligand combination of (R,S)-N-Me-3,5-xylyl-BoPhoz and tris(3,5-xylyl)phosphine provided benzylic alcohols in good yields and enantioselectivities. The electronic and steric characteristics of the ancillary triarylphosphine were important in determining both reactivity and selectivity. PMID:23980941

  13. The effect of ketone bodies on renal ammoniogenesis

    PubMed Central

    Lemieux, Guy; Vinay, Patrick; Robitaille, Pierre; Plante, Gérard E.; Lussier, Yolande; Martin, Pierre

    1971-01-01

    Infusion of ketone bodies to ammonium chloride-loaded acidotic dogs was found to induce significant reduction in urinary excretion of ammonia. This effect could not be attributed to urinary pH variations. Total ammonia production by the left kidney was measured in 25 animals infused during 90 min with the sodium salt of D,L-β-hydroxybutyric acid adjusted to pH 6.0 or 4.2. Ketonemia averaged 4.5 mM/liter. In all experiments the ammonia content of both urine and renal venous blood fell markedly so that ammoniogenesis was depressed by 60% or more within 60 min after the onset of infusion. Administration of equimolar quantities of sodium acetoacetate adjusted to pH 6.0 resulted in a 50% decrease in renal ammonia production. Infusion of ketone bodies adjusted to pH 6.0 is usually accompanied by a small increase in extracellular bicarbonate (3.7 mM/liter). However infusion of D,L-sodium lactate or sodium bicarbonate in amounts sufficient to induce a similar rise in plasma bicarbonate resulted in only a slight decrement in ammonia production (15%). The continuous infusion of 5% mannitol alone during 90-150 min failed to influence renal ammoniogenesis. Infusion of pure sodium-free β-hydroxybutyric acid prepared by ion exchange (pH 2.2) resulted in a 50% decrease in renal ammoniogenesis in spite of the fact that both urinary pH and plasma bicarbonate fell significantly. During all experiments where ketones were infused, the renal extraction of glutamine became negligible as the renal glutamine arteriovenous difference was abolished. Renal hemodynamics did not vary significantly. Infusion of β-hydroxybutyrate into the left renal artery resulted in a rapid decrease in ammoniogenesis by the perfused kidney. The present study indicates that ketone bodies exert their inhibitory influence within the renal tubular cell. Since their effect is independent of urinary or systemic acid-base changes, it is suggested that they depress renal ammoniogenesis by preventing the

  14. Can Ketones Help Rescue Brain Fuel Supply in Later Life? Implications for Cognitive Health during Aging and the Treatment of Alzheimer’s Disease

    PubMed Central

    Cunnane, Stephen C.; Courchesne-Loyer, Alexandre; Vandenberghe, Camille; St-Pierre, Valérie; Fortier, Mélanie; Hennebelle, Marie; Croteau, Etienne; Bocti, Christian; Fulop, Tamas; Castellano, Christian-Alexandre

    2016-01-01

    We propose that brain energy deficit is an important pre-symptomatic feature of Alzheimer’s disease (AD) that requires closer attention in the development of AD therapeutics. Our rationale is fourfold: (i) Glucose uptake is lower in the frontal cortex of people >65 years-old despite cognitive scores that are normal for age. (ii) The regional deficit in brain glucose uptake is present in adults <40 years-old who have genetic or lifestyle risk factors for AD but in whom cognitive decline has not yet started. Examples include young adult carriers of presenilin-1 or apolipoprotein E4, and young adults with mild insulin resistance or with a maternal family history of AD. (iii) Regional brain glucose uptake is impaired in AD and mild cognitive impairment (MCI), but brain uptake of ketones (beta-hydroxybutyrate and acetoacetate), remains the same in AD and MCI as in cognitively healthy age-matched controls. These observations point to a brain fuel deficit which appears to be specific to glucose, precedes cognitive decline associated with AD, and becomes more severe as MCI progresses toward AD. Since glucose is the brain’s main fuel, we suggest that gradual brain glucose exhaustion is contributing significantly to the onset or progression of AD. (iv) Interventions that raise ketone availability to the brain improve cognitive outcomes in both MCI and AD as well as in acute experimental hypoglycemia. Ketones are the brain’s main alternative fuel to glucose and brain ketone uptake is still normal in MCI and in early AD, which would help explain why ketogenic interventions improve some cognitive outcomes in MCI and AD. We suggest that the brain energy deficit needs to be overcome in order to successfully develop more effective therapeutics for AD. At present, oral ketogenic supplements are the most promising means of achieving this goal. PMID:27458340

  15. Can Ketones Help Rescue Brain Fuel Supply in Later Life? Implications for Cognitive Health during Aging and the Treatment of Alzheimer's Disease.

    PubMed

    Cunnane, Stephen C; Courchesne-Loyer, Alexandre; Vandenberghe, Camille; St-Pierre, Valérie; Fortier, Mélanie; Hennebelle, Marie; Croteau, Etienne; Bocti, Christian; Fulop, Tamas; Castellano, Christian-Alexandre

    2016-01-01

    We propose that brain energy deficit is an important pre-symptomatic feature of Alzheimer's disease (AD) that requires closer attention in the development of AD therapeutics. Our rationale is fourfold: (i) Glucose uptake is lower in the frontal cortex of people >65 years-old despite cognitive scores that are normal for age. (ii) The regional deficit in brain glucose uptake is present in adults <40 years-old who have genetic or lifestyle risk factors for AD but in whom cognitive decline has not yet started. Examples include young adult carriers of presenilin-1 or apolipoprotein E4, and young adults with mild insulin resistance or with a maternal family history of AD. (iii) Regional brain glucose uptake is impaired in AD and mild cognitive impairment (MCI), but brain uptake of ketones (beta-hydroxybutyrate and acetoacetate), remains the same in AD and MCI as in cognitively healthy age-matched controls. These observations point to a brain fuel deficit which appears to be specific to glucose, precedes cognitive decline associated with AD, and becomes more severe as MCI progresses toward AD. Since glucose is the brain's main fuel, we suggest that gradual brain glucose exhaustion is contributing significantly to the onset or progression of AD. (iv) Interventions that raise ketone availability to the brain improve cognitive outcomes in both MCI and AD as well as in acute experimental hypoglycemia. Ketones are the brain's main alternative fuel to glucose and brain ketone uptake is still normal in MCI and in early AD, which would help explain why ketogenic interventions improve some cognitive outcomes in MCI and AD. We suggest that the brain energy deficit needs to be overcome in order to successfully develop more effective therapeutics for AD. At present, oral ketogenic supplements are the most promising means of achieving this goal. PMID:27458340

  16. Human ketone body production and utilization studied using tracer techniques: Regulation by free fatty acids, insulin, catecholamines, and thyroid hormones

    SciTech Connect

    Keller, U.; Lustenberger, M.; Mueller-Brand, J.G.; Gerber, P.P.; Stauffacher, W.

    1989-05-01

    Ketone body concentrations fluctuate markedly during physiological and pathological conditions. Tracer techniques have been developed in recent years to study production, utilization, and the metabolic clearance rate of ketone bodies. This review describes data on the roles of insulin, catecholamines, and thyroid hormones in the regulation of ketone body kinetics. The data indicate that insulin lowers ketone body concentrations by three independent mechanisms: first, it inhibits lipolysis, and thus lowers free fatty acid availability for ketogenesis; second, it restrains ketone body production within the liver; third, it enhances peripheral ketone body utilization. To assess these effects in humans in vivo, experimental models were developed to study insulin effects with controlled concentrations of free fatty acids, insulin, glucagon, and ketone bodies. Presently available data also support an important role of catecholamines in increasing ketone body concentrations. Evidence was presented that norepinephrine increases ketogenesis not only by stimulating lipolysis, and thus releasing free fatty acids, but also by increasing intrahepatic ketogenesis. Thyroid hormone availability was associated with lipolysis and ketogenesis. Ketone body concentrations after an overnight fast were only modestly elevated in hyperthyroidism resulting from increased peripheral ketone body clearance. There was a significant correlation between serum triiodothyronine levels and the ketone body metabolic clearance rate. Thus, ketone body homeostasis in human subjects resulted from the interaction of hormones such as insulin, catecholamines, and thyroid hormones regulating lipolysis, intrahepatic ketogenesis, and peripheral ketone body utilization. 58 references.

  17. Synthesis, conformational parameters and packing considerations of methyl bispyridyl ketones

    NASA Astrophysics Data System (ADS)

    Weck, Christian; Katzsch, Felix; Gruber, Tobias

    2015-10-01

    The crystal structures of two bispyridyl ketones featuring either two methyl residues or one methyl and one bromomethyl residue, respectively, are presented. In order to elucidate the influence of the substituents, a comprehensive comparison with the non-methylated mother compound has been performed. A special focus lies thereby on the relative position of the heteroatoms and their free electron pairs. The two methyl groups at the bispyridyl ketone result in two molecules in the asymmetric unit adopting rather different conformations. Due to the fast crystallization conditions and a melting point differing from the literature, a polymorph close to a local minimum in the energy hypersurface seems possible. After introducing a bromine atom to one of the two methyl groups, the molecular conformation is very similar to the unsubstituted molecule. The packing of both title compounds is dominated by weak contacts of the C-H⋯π and C-H⋯Y type (Y = O, N) and C-H⋯Br- and Br⋯π-contacts for the brominated molecule.

  18. Activation of Acetone and Other Simple Ketones in Anaerobic Bacteria.

    PubMed

    Heider, Johann; Schühle, Karola; Frey, Jasmin; Schink, Bernhard

    2016-01-01

    Acetone and other ketones are activated for subsequent degradation through carboxylation by many nitrate-reducing, phototrophic, and obligately aerobic bacteria. Acetone carboxylation leads to acetoacetate, which is subsequently activated to a thioester and degraded via thiolysis. Two different types of acetone carboxylases have been described, which require either 2 or 4 ATP equivalents as an energy supply for the carboxylation reaction. Both enzymes appear to combine acetone enolphosphate with carbonic phosphate to form acetoacetate. A similar but more complex enzyme is known to carboxylate the aromatic ketone acetophenone, a metabolic intermediate in anaerobic ethylbenzene metabolism in denitrifying bacteria, with simultaneous hydrolysis of 2 ATP to 2 ADP. Obligately anaerobic sulfate-reducing bacteria activate acetone to a four-carbon compound as well, but via a different process than bicarbonate- or CO2-dependent carboxylation. The present evidence indicates that either carbon monoxide or a formyl residue is used as a cosubstrate, and that the overall ATP expenditure of this pathway is substantially lower than in the known acetone carboxylase reactions. PMID:26958851

  19. Use of isotope effects to characterize intermediates in mechanism-based inactivation of dopamine beta-monooxygenase by beta-chlorophenethylamine

    SciTech Connect

    Bossard, M.J.; Klinman, J.P. )

    1990-04-05

    A mechanism for beta-chlorophenethylamine inhibition of dopamine beta-monooxygenase has been postulated in which bound alpha-aminoacetophenone is generated followed by an intramolecular redox reaction to yield a ketone-derived radical cation as the inhibitory species. Based on the assumption that the ketone radical is the inhibitory intermediate, an analogous system was predicted and verified. In the present study, the role of alpha-aminoacetophenone as the proposed intermediate in the inactivation by beta-chlorophenethylamine was examined in greater detail. From the interdependence of tyramine and alpha-aminoacetophenone concentrations, ketone inactivation is concluded to occur at the substrate site as opposed to potential binding at the reductant-binding site. Using beta-(2-1H)- and beta-(2-2H)chlorophenethylamine, the magnitude of the deuterium isotope effect on inactivation under second-order conditions has been found to be identical to that observed under catalytic turnover, D(kappa inact/Ki) = D(kappa cat/Km) = 6-7. By contrast, the isotope effect on inactivation under conditions of substrate and oxygen saturation, D kappa inact = 2, is 3-fold smaller than that seen on catalytic turnover, D kappa cat = 6. This reduced isotope effect for inactivation is attributed to a normal isotope effect on substrate hydroxylation followed by an inverse isotope effect on the partitioning of the enol of alpha-aminoacetophenone between oxidation to a radical cation versus protonation to regenerate ketone. These findings are unusual in that two isotopically sensitive steps are present in the inactivation pathway whereas only one is observable in turnover.

  20. Enantioselective Reduction of Ketones and Imines Catalyzed by (CN-Box)Re(V)-Oxo Complexes

    PubMed Central

    Nolin, Kristine A.; Ahn, Richard W.; Kobayashi, Yusuke; Kennedy-Smith, Joshua J.

    2012-01-01

    The development and application of chiral, non-racemic Re(V)-oxo complexes to the enantioselective reduction of prochiral ketones is described. In addition to the enantioselective reduction of prochiral ketones, we report the application of these complexes to (1) a tandem Meyer-Schuster rearrangement/reduction to access enantioenriched allylic alcohols and (2) the enantioselective reduction of imines. PMID:20623567

  1. Raspberry Ketone Trifluoroacetate, a new attractant for the Queensland fruit fly (Bactrocera tryoni (Froggatt))

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Queensland fruit fly (Bactrocera tryoni, Q-fly) is a major agricultural pest in eastern Australia. The deployment of male lures comprises an important component of several control and detection strategies for this pest. A novel fluorinated analog of raspberry ketone, raspberry ketone trifluoroac...

  2. Further research on the biological activities and the safety of raspberry ketone are needed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Raspberry ketone supplements have grabbed consumer attention with the possibility they might help burn fat and aid weight loss. While raspberry ketone occurs naturally, and is found in raspberry fruit, most is synthetically produced for use in commercial products as flavorings, fragrances, or dietar...

  3. Visible-Light Induced Direct Synthesis of Polysubstituted Furans from Cyclopropyl Ketones.

    PubMed

    Feng, Liyan; Yan, Hang; Yang, Chao; Chen, Dafa; Xia, Wujiong

    2016-08-19

    In this article, a photoredox protocol for the synthesis of furans via oxidative coupling of olefin generated in situ from cyclopropyl ketones with ketonic oxygen atom is presented. Moreover, bromination of furans in the presence of overstoichiometric oxidant has been achieved with high regioselectivity. PMID:27167091

  4. 40 CFR 721.10413 - Fluorinated dialkyl ketone (generic) (P-10-135).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) (P-10-135). 721.10413 Section 721.10413 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.10413 Fluorinated dialkyl ketone (generic) (P-10-135). (a) Chemical... as fluorinated dialkyl ketone (PMN P-10-135) is subject to reporting under this section for...

  5. 40 CFR 721.10417 - Biphenyl alkyl morpholino ketone (generic) (P-11-338).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (generic) (P-11-338). 721.10417 Section 721.10417 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.10417 Biphenyl alkyl morpholino ketone (generic) (P-11-338). (a... generically as biphenyl alkyl morpholino ketone (PMN P-11-338) is subject to reporting under this section...

  6. 40 CFR 721.10413 - Fluorinated dialkyl ketone (generic) (P-10-135).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) (P-10-135). 721.10413 Section 721.10413 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.10413 Fluorinated dialkyl ketone (generic) (P-10-135). (a) Chemical... as fluorinated dialkyl ketone (PMN P-10-135) is subject to reporting under this section for...

  7. 40 CFR 721.10413 - Fluorinated dialkyl ketone (generic) (P-10-135).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) (P-10-135). 721.10413 Section 721.10413 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.10413 Fluorinated dialkyl ketone (generic) (P-10-135). (a) Chemical... as fluorinated dialkyl ketone (PMN P-10-135) is subject to reporting under this section for...

  8. 40 CFR 721.10417 - Biphenyl alkyl morpholino ketone (generic) (P-11-338).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (generic) (P-11-338). 721.10417 Section 721.10417 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.10417 Biphenyl alkyl morpholino ketone (generic) (P-11-338). (a... generically as biphenyl alkyl morpholino ketone (PMN P-11-338) is subject to reporting under this section...

  9. 40 CFR 721.10417 - Biphenyl alkyl morpholino ketone (generic) (P-11-338).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (generic) (P-11-338). 721.10417 Section 721.10417 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.10417 Biphenyl alkyl morpholino ketone (generic) (P-11-338). (a... generically as biphenyl alkyl morpholino ketone (PMN P-11-338) is subject to reporting under this section...

  10. Beyond ketonization: selective conversion of carboxylic acids to olefins over balanced Lewis acid-base pairs.

    PubMed

    Baylon, Rebecca A L; Sun, Junming; Martin, Kevin J; Venkitasubramanian, Padmesh; Wang, Yong

    2016-04-11

    We report the direct conversion of mixed carboxylic acids to C-C olefins with up to 60 mol% carbon yield through cascade (cross) ketonization, (cross) aldolization and self-deoxygenation reactions. Co-feeding hydrogen provides an additional ketone hydrogenation/dehydration pathway to a wider range of olefins. PMID:26898532

  11. Proton-exchange membrane materials based on blends of poly(ether ketone ketone) and poly(ether imide)

    NASA Astrophysics Data System (ADS)

    Swier, S.; Gasa, J.; Shaw, M. T.; Weiss, R. A.

    2004-03-01

    The development of materials for proton-exchange membranes (PEM) involves finding a compromise between high proton conductivities and sufficient mechanical and chemical stability to withstand the conditions in the fuel cell. The currently used perfluorinated polymer electrolyte membranes tend to be expensive and have problems in case of extensive application. New polymer electrolytes based on hydrocarbon polymers are therefore the focus of a considerable research effort. Blends of sulfonated poly(ether ketone ketone) (SPEKK) and poly(ether imide) (PEI) were evaluated as PEMs. Sulfonation of PEKK was achieved by using a mixture of concentrated sulfuric acid and fuming sulfuric acid, and blend membranes were prepared by casting a solution of the two polymers in N-methyl-2- pyrrolidone. The hydration level of the membrane decreased with increasing PEI concentration, but a proton conductivity comparable to NafionTM was obtained for blends containing less than 20 wt% PEI. The fuel cell performance of the membranes was affected by the sulfonation level of the PEKK, the blend composition and the casting procedure employed. The state of water in the membrane was evaluated from the depression of the glass transition and from the melting endotherms associated with water. Proton conductivity depended strongly on the hydration number (water molecules per sulfonate group), which depended on the sulfonation level of the PEKK and the blend morphology. Sorption data from gravimetric techniques provided important transport information like the solubility and diffusivity of water and methanol.

  12. Interfacial interactions of poly(ether ketone ketone) polymer coatings onto oxide-free phosphate films on an aluminum surface

    SciTech Connect

    Asunskis, A. L.; Sherwood, P. M. A.

    2007-07-15

    This article continues a series of papers that shows how thin (10 nm or less) oxide-free phosphate films can be formed on a number of metals. The films formed have potential as corrosion resistant films. Previous papers have shown that it is possible to extend the range of the surface coatings that can be formed by placing a thin polymer layer over the phosphate layer. In this work it is shown how the water insoluble polymer poly(ether ketone ketone) (PEKK) can be placed over a thin oxide-free phosphate film on aluminum metal. The surface and the interfaces involved were studied by valence band and core level x-ray photoelectron spectroscopy. Difference spectra in the valence band region were used to show that there is a chemical interaction between the PEKK and phosphate thin films on the aluminum metal. Three different phosphate film compositions were studied using different phosphorous containing acids, H{sub 3}PO{sub 4}, H{sub 3}PO{sub 3}, and H{sub 3}PO{sub 2}. This type of interaction illustrates the potential of phosphates to act as adhesion promoters. The valence band spectra are interpreted by calculations.

  13. The rotational spectrum of Roesky’s ketone

    NASA Astrophysics Data System (ADS)

    Blockhuys, Frank; Tersago, Karla; Shlykov, Sergey A.; Konrad, Alexander; Christen, Dines

    2010-08-01

    The experimental rotational spectrum of 5-oxo-1,3,2,4-dithiadiazole (Roesky's ketone) has been recorded and the experimental rotational constants have been determined. The latter have been used to evaluate the performance of a large number of quantum chemical methods combined with different basis sets, by comparing the calculated with the experimental values. The results of this comparison indicate that, in general, the wave-function-based methods perform better than those from Density Functional Theory. Four of the 42 investigated method/basis set combinations prove to be the most valuable, i.e., MP4(SDQ)/(aug-)cc-pVTZ, B3PW91/cc-pV(T+d)Z and MPW1PW91/aug-cc-pVTZ, as they produce rotational constants with a root-mean-square deviation from the experimental values of only about 5 MHz.

  14. Electron impact ionization of cycloalkanes, aldehydes, and ketones

    SciTech Connect

    Gupta, Dhanoj; Antony, Bobby

    2014-08-07

    The theoretical calculations of electron impact total ionization cross section for cycloalkane, aldehyde, and ketone group molecules are undertaken from ionization threshold to 2 keV. The present calculations are based on the spherical complex optical potential formalism and complex scattering potential ionization contribution method. The results of most of the targets studied compare fairly well with the recent measurements, wherever available and the cross sections for many targets are predicted for the first time. The correlation between the peak of ionization cross sections with number of target electrons and target parameters is also reported. It was found that the cross sections at their maximum depend linearly with the number of target electrons and with other target parameters, confirming the consistency of the values reported here.

  15. Breath Ketone Testing: A New Biomarker for Diagnosis and Therapeutic Monitoring of Diabetic Ketosis

    PubMed Central

    Qiao, Yue; Gao, Zhaohua; Liu, Yong; Cheng, Yan; Yu, Mengxiao; Zhao, Lingling

    2014-01-01

    Background. Acetone, β-hydroxybutyric acid, and acetoacetic acid are three types of ketone body that may be found in the breath, blood, and urine. Detecting altered concentrations of ketones in the breath, blood, and urine is crucial for the diagnosis and treatment of diabetic ketosis. The aim of this study was to evaluate the advantages of different detection methods for ketones, and to establish whether detection of the concentration of ketones in the breath is an effective and practical technique. Methods. We measured the concentrations of acetone in the breath using gas chromatography-mass spectrometry and β-hydroxybutyrate in fingertip blood collected from 99 patients with diabetes assigned to groups 1 (−), 2 (±), 3 (+), 4 (++), or 5 (+++) according to urinary ketone concentrations. Results. There were strong relationships between fasting blood glucose, age, and diabetic ketosis. Exhaled acetone concentration significantly correlated with concentrations of fasting blood glucose, ketones in the blood and urine, LDL-C, creatinine, and blood urea nitrogen. Conclusions. Breath testing for ketones has a high sensitivity and specificity and appears to be a noninvasive, convenient, and repeatable method for the diagnosis and therapeutic monitoring of diabetic ketosis. PMID:24900994

  16. Homogenization and lipase treatment of milk and resulting methyl ketone generation in blue cheese.

    PubMed

    Cao, Mingkai; Fonseca, Leorges M; Schoenfuss, Tonya C; Rankin, Scott A

    2014-06-25

    A specific range of methyl ketones contribute to the distinctive flavor of traditional blue cheeses. These ketones are metabolites of lipid metabolism by Penicillium mold added to cheese for this purpose. Two processes, namely, the homogenization of milk fat and the addition of exogenous lipase enzymes, are traditionally applied measures to control the formation of methyl ketones in blue cheese. There exists little scientific validation of the actual effects of these treatments on methyl ketone development. The present study evaluated the effects of milk fat homogenization and lipase treatments on methyl ketone and free fatty acid development using sensory methods and the comparison of selected volatile quantities using gas chromatography. Initial work was conducted using a blue cheese system model; subsequent work was conducted with manufactured blue cheese. In general, there were modest effects of homogenization and lipase treatments on free fatty acid (FFA) and methyl ketone concentrations in blue cheese. Blue cheese treatments involving Penicillium roqueforti lipase with homogenized milk yielded higher FFA and methyl ketone levels, for example, a ∼20-fold increase for hexanoic acid and a 3-fold increase in 2-pentanone. PMID:24460517

  17. A new alternative to expandable pedicle screws: Expandable poly-ether-ether-ketone shell.

    PubMed

    Demir, Teyfik

    2015-05-01

    Screw pullout is a very common problem in the fixation of sacrum with pedicle screws. The principal cause of this problem is that the cyclic micro motions in the fixation of sacrum are higher than the other regions of the vertebrae that limit the osteo-integration between bone and screw. In addition to that, the bone quality is very poor at sacrum region. This study investigated a possible solution to the pullout problem without the expandable screws' handicaps. Newly designed poly-ether-ether-ketone expandable shell and classical pedicle screws were biomechanically compared. Torsion test, pullout tests, fatigue tests, flexion/extension moment test, axial gripping capacity tests and torsional gripping capacity tests were conducted in accordance with ASTM F543, F1798 and F1717. Standard polyurethane foam and calf vertebrae were used as embedding medium for pullout tests. Classical pedicle screw pullout load on polyurethane foam was 564.8 N compared to the failure load for calf vertebrae's 1264 N. Under the same test conditions, expandable poly-ether-ether-ketone shell system's pullout loads from polyurethane foam and calf vertebrae were 1196.3 and 1890 N, respectively. The pullout values for expandable poly-ether-ether-ketone shell were 33% and 53% higher than classical pedicle screw on polyurethane foam and calf vertebrae, respectively. The expandable poly-ether-ether-ketone shell exhibited endurance on its 90% of yield load. Contrary to poly-ether-ether-ketone shell, classical pedicle screw exhibited endurance on 70% of its yield load. Expandable poly-ether-ether-ketone shell exhibited much higher pullout performance than classical pedicle screw. Fatigue performance of expandable poly-ether-ether-ketone shell is also higher than classical pedicle screw due to damping the micro motion capacity of the poly-ether-ether-ketone. Expandable poly-ether-ether-ketone shell is a safe alternative to all other expandable pedicle screw systems on mechanical perspective

  18. Intermolecular reductive coupling of esters with benzophenones by low-valent titanium: synthesis of diarylmethyl ketones revisited.

    PubMed

    Kise, Naoki; Sakurai, Toshihiko

    2015-04-01

    The reductive coupling of aliphatic esters with benzophenones by Zn-TiCl4 in THF gave two- and four-electron reduced products, diaryl(hydroxy)methyl ketones, and diarylmethyl ketones selectively by controlling the reaction conditions. In the reaction of aromatic esters with benzophenones, diarylmethyl ketones were obtained as the sole products. N-(Alkoxycarbonyl)-(S)-α-amino acid methyl esters gave optically active diphenylmethyl ketones by reduction with benzophenone. The obtained diphenylmethyl ketones were transformed to 4,5-cis-disubstituted oxazolidin-2-ones stereoselectively. PMID:25748528

  19. Iridium-Catalyzed Diastereoselective and Enantioselective Allylic Substitutions with Acyclic α-Alkoxy Ketones.

    PubMed

    Jiang, Xingyu; Chen, Wenyong; Hartwig, John F

    2016-05-01

    The asymmetric alkylation of acyclic ketones is a longstanding challenge in organic synthesis. Reported herein are diastereoselective and enantioselective allylic substitutions with acyclic α-alkoxy ketones catalyzed by a metallacyclic iridium complex to form products with contiguous stereogenic centers derived from the nucleophile and electrophile. These reactions occur between allyl methyl carbonates and unstabilized copper(I) enolates generated in situ from acyclic α-alkoxy ketones. The resulting products can be readily converted into enantioenriched tertiary alcohols and tetrahydrofuran derivatives without erosion of enantiomeric purity. PMID:27038004

  20. Identifying a Highly Active Copper Catalyst for KA(2) Reaction of Aromatic Ketones.

    PubMed

    Cai, Yujuan; Tang, Xinjun; Ma, Shengming

    2016-02-12

    The well-established A(3) coupling reaction of terminal alkynes, aldehydes, and amines provides the most straightforward approach to propargylic amines. However, the related reaction of ketones, especially aromatic ketones, is still a significant challenge. A highly efficient catalytic protocol has been developed for the coupling of aromatic ketones with amines and terminal alkynes, in which Cu(I) , generated in situ from the reduction of CuBr2 with sodium ascorbate, has been identified as the highly efficient catalyst. Since propargylic amines are versatile synthetic intermediates and important units in pharmaceutical products, such an advance will greatly stimulate research interest involving the previously unavailable propargylic amines. PMID:26660459

  1. Iron Mineral Effects on Ketone Reactions in Hydrothermal Fluids

    NASA Astrophysics Data System (ADS)

    Yang, Z.; Gould, I. R.; Shock, E.

    2011-12-01

    Interactions in hydrothermal environments suggest that minerals participate in and alter organic compounds transformations at high temperatures and pressures [1]. Our previous experimental studies of a model ketone (dibenzyl ketone, DBK) in aqueous media under hydrothermal conditions (700 bars, 300 °C) indicate low conversion but multiple reaction pathways yielding diverse products. In the absence of minerals, DBK not only reversibly interconverts into 1,3-diphenyl-2-propanol, 1,3-diphenylpropene and 1,3-diphenylpropane along a reduction pathway, but also yields products including toluene, bibenzyl, stilbene and conjugated, dehydrogenated three- and four-ring coupling products from carbon-carbon (C-C) and carbon-hydrogen (C-H) bond-breaking pathways. Experiments involving oxide minerals that are not sensitive to redox process, such as quartz and corundum, show no effect when compared with H2O alone in changing DBK hydrothermal reactions and product distributions. In the presence of iron bearing minerals, however, we observe that the overall reaction conversion of DBK increases by orders of magnitude, and that reaction pathways are controlled or favored differently if hematite (Fe2O3), magnetite (Fe3O4) or ferrous sulfide (FeS) is present. As an example, with the same mineral surface area, Fe2O3 expedites DBK conversion from 6.4% (H2O only) to 26.4% after 168 hours, while Fe3O4 increases conversion up to 46.8%. Although more products are formed with introduction of iron oxide minerals, the major products are identical to those found in H2O alone, such as toluene, bibenzyl and a few large coupling products from the bond-breaking pathways. Hydrothermal experiments using a synthesized asymmetrical p-methyl-DBK under the same conditions conducted with Fe2O3 and Fe3O4 are consistent with those for DBK, showing higher conversion than in H2O, and more bond-breaking products like toluene, p-xylene, and three kinds of bibenzyls. This suggests that both Fe2O3 and Fe3O4

  2. Solvent-induced crystallization of poly(ether ether ketone)

    NASA Astrophysics Data System (ADS)

    McPeak, Jennifer Lynne

    The purpose of this study was learn how the diffusion, swelling, and crystallization processes are coupled during solvent-induced crystallization of poly(ether ether ketone) (PEEK). Unoriented amorphous PEEK films were immersed in aprotic organic liquids at ambient temperature and bulk properties or characteristics were monitored as a function of immersion time. The sorption behavior, T g and Tm° suppression, crystallinity, and dynamic mechanical response were correlated as a function of solvent chemistry and immersion time. The saturation time of methylene chloride, 1,3-dichloropropane, tetrahydrofuran, cyclopentanone, chlorobenzene, toluene, diethyl ketone, and ethylbenzene in amorphous PEEK films were found to range from hours to days depending on the level of polymer-solvent interactions. In-situ isochronal DMA spectra show that the Tg of PEEK was suppressed from 150°C to below ambient temperature such that crystallization was kinetically feasible during ambient immersion. In addition, an increase in viscoelastic dispersion was attributed to the presence of crystallinity. From dynamic mass uptake and wide-angle x-ray diffraction (WAXD) results, it was found that the bulk sorption rate was equal to the bulk crystallization rate for all solvent systems that promoted SINC and PEEK exhibited diffusion-limited crystallization, irrespective of the nature of the transport mechanism. In addition, the solvent-induced crystals exhibit preferred orientation as supported by photographic WAXD. A distinct sorption front, observed with scanning electron microscopy, further supports the scenario of diffusion-controlled crystallization and one-dimensional diffusion. Isothermal DMA spectra for THF, cyclopentanone, and chlorobenzene, indicate that, as the solvent diffuses into the films, the stiffness of the polymer decreases at short times, begins to increase, and then reaches a relatively time-independent value. It was determined that the initial decrease in the storage

  3. Synthesis of Acridines by the [4 + 2] Annulation of Arynes and 2-Aminoaryl Ketones

    PubMed Central

    Rogness, Donald C.; Larock, Richard C.

    2010-01-01

    The reaction of 2-aminoaryl ketones and arynes generated by the treatment of various o-(trimethylsilyl)aryl triflates with CsF results in [4 + 2] annulation to afford substituted acridines in good yields. PMID:20222700

  4. Constituents of Artemisia gmelinii Weber ex Stechm. from Uttarakhand Himalaya: A Source of Artemisia Ketone.

    PubMed

    Haider, S Z; Andola, H C; Mohan, M

    2012-05-01

    The essential oils isolated from the aerial parts of two different populations of Artemisia gmelinii growing in Uttarakhand Himalaya region were analysed by gas chromatography and gas chromatography/mass spectrometry (GC-MS) in order to determine the variation of concentration in their constituents. Artemisia ketone was detected as a major constituent in both the populations i.e., Niti valley and Jhelum samples. Niti oil was found to have considerably greater amounts of artemesia ketone (53.34%) followed by α-thujone (9.91%) and 1,8-cineole (6.57%), Similarly, the first major compound in Jhelum oil was artemesia ketone (40.87%), whereas ar-curcumene (8.54%) was identified as a second major compound followed by α-thujone (4.04%). Artemisia ketone can be useful for perfumery and fragrance to introduce new and interesting herbaceous notes. PMID:23439844

  5. Transition metal-catalyzed ketone-directed or mediated C-H functionalization.

    PubMed

    Huang, Zhongxing; Lim, Hee Nam; Mo, Fanyang; Young, Michael C; Dong, Guangbin

    2015-11-01

    Transition metal-catalyzed C-H functionalization has evolved into a prominent and indispensable tool in organic synthesis. While nitrogen, phosphorus and sulfur-based functional groups (FGs) are widely employed as effective directing groups (DGs) to control the site-selectivity of C-H activation, the use of common FGs (e.g. ketone, alcohol and amine) as DGs has been continuously pursued. Ketones are an especially attractive choice of DGs and substrates due to their prevalence in various molecules and versatile reactivity as synthetic intermediates. Over the last two decades, transition metal-catalyzed C-H functionalization that is directed or mediated by ketones has experienced vigorous growth. This review summarizes these advancements into three major categories: use of ketone carbonyls as DGs, direct β-functionalization, and α-alkylation/alkenylation with unactivated olefins and alkynes. Each of these subsections is discussed from the perspective of strategic design and reaction discovery. PMID:26185960

  6. Structural and functional analysis of two di-domain aromatase/cyclases from type II polyketide synthases

    PubMed Central

    Caldara-Festin, Grace; Jackson, David R.; Barajas, Jesus F.; Valentic, Timothy R.; Patel, Avinash B.; Aguilar, Stephanie; Nguyen, MyChi; Vo, Michael; Khanna, Avinash; Sasaki, Eita; Liu, Hung-wen; Tsai, Shiou-Chuan

    2015-01-01

    Aromatic polyketides make up a large class of natural products with diverse bioactivity. During biosynthesis, linear poly-β-ketone intermediates are regiospecifically cyclized, yielding molecules with defined cyclization patterns that are crucial for polyketide bioactivity. The aromatase/cyclases (ARO/CYCs) are responsible for regiospecific cyclization of bacterial polyketides. The two most common cyclization patterns are C7–C12 and C9–C14 cyclizations. We have previously characterized three monodomain ARO/CYCs: ZhuI, TcmN, and WhiE. The last remaining uncharacterized class of ARO/CYCs is the di-domain ARO/CYCs, which catalyze C7–C12 cyclization and/or aromatization. Di-domain ARO/CYCs can further be separated into two subclasses: “nonreducing” ARO/CYCs, which act on nonreduced poly-β-ketones, and “reducing” ARO/CYCs, which act on cyclized C9 reduced poly-β-ketones. For years, the functional role of each domain in cyclization and aromatization for di-domain ARO/CYCs has remained a mystery. Here we present what is to our knowledge the first structural and functional analysis, along with an in-depth comparison, of the nonreducing (StfQ) and reducing (BexL) di-domain ARO/CYCs. This work completes the structural and functional characterization of mono- and di-domain ARO/CYCs in bacterial type II polyketide synthases and lays the groundwork for engineered biosynthesis of new bioactive polyketides. PMID:26631750

  7. Efficient Domino Hydroformylation/Benzoin Condensation: Highly Selective Synthesis of α-Hydroxy Ketones.

    PubMed

    Dong, Kaiwu; Sang, Rui; Soule, Jean-Francois; Bruneau, Christian; Franke, Robert; Jackstell, Ralf; Beller, Matthias

    2015-12-01

    An improved domino hydroformylation/benzoin condensation to give α-hydroxy ketones has been developed. Easily available olefins are smoothly converted into the corresponding α-hydroxy ketones in high yields with excellent regioselectivities. Key to success is the use of a specific catalytic system consisting of a rhodium/phosphine complex and the CO2 adduct of an N-heterocyclic carbene. PMID:26503672

  8. Photoredox Activation for the Direct β-Arylation of Ketones and Aldehydes

    PubMed Central

    Pirnot, Michael T.; Rankic, Danica A.; Martin, David B. C.; MacMillan, David W. C.

    2013-01-01

    The direct β-activation of saturated aldehydes and ketones has long been an elusive transformation. We found that photoredox catalysis in combination with organocatalysis can lead to the transient generation of 5π-electron β-enaminyl radicals from ketones and aldehydes that rapidly couple with cyano-substituted aryl rings at the carbonyl β-position. This mode of activation is suitable for a broad range of carbonyl β-functionalization reactions and is amenable to enantioselective catalysis. PMID:23539600

  9. Synthesis of cyclic enones via direct palladium-catalyzed aerobic dehydrogenation of ketones.

    PubMed

    Diao, Tianning; Stahl, Shannon S

    2011-09-21

    α,β-Unsaturated carbonyl compounds are versatile intermediates in the synthesis of pharmaceuticals and biologically active compounds. Here, we report the discovery and application of Pd(DMSO)(2)(TFA)(2) as a catalyst for direct dehydrogenation of cyclohexanones and other cyclic ketones to the corresponding enones, using O(2) as the oxidant. The substrate scope includes heterocyclic ketones and several natural-product precursors. PMID:21851123

  10. Synthesis of Cyclic Enones via Direct Palladium-Catalyzed Aerobic Dehydrogenation of Ketones

    PubMed Central

    Diao, Tianning

    2011-01-01

    α,β-Unsaturated carbonyl compounds are versatile intermediates in the synthesis of pharmaceuticals and biologically active compounds. Here, we report the discovery and application of Pd(DMSO)2(TFA)2 as a catalyst for direct dehydrogenation of cyclohexanones and other cyclic ketones to the corresponding enones, using O2 as the oxidant. The substrate scope includes heterocyclic ketones and several natural-product precursors. PMID:21851123

  11. Flow-Induced Crystallization of Poly(ether ether ketone)

    NASA Astrophysics Data System (ADS)

    Nazari, Behzad; Rhoades, Alicyn; Colby, Ralph

    The effects of an interval of shear above the melting temperature Tm on subsequent isothermal crystallization below Tm is reported for the premier engineering thermoplastic, poly(ether ether ketone) (PEEK). The effect of shear on the crystallization rate of PEEK is investigated by means of rheological techniques and differential scanning calorimetry (DSC) under a protocol of imposing shear in a rotational cone and plate rheometer and monitoring crystallization after quenching. The rate of crystallization at 320 °C was not affected by shear for shear rates <7 s-1 at 350 °C, whereas intervals of adequate shear at higher shear rates prior to the quench to 320 °C accelerated crystallization significantly. As the duration of the interval of shear above 7 s-1 is increased, the crystallization time decreases but at each shear rate eventually saturates once the applied specific work exceeds ~120 MPa. The annealing of the flow-induced precursors was also investigated. The nuclei were fairly persistent at temperatures close to 350 °C, however very unstable at temperatures above 375 °C. This suggests that the nanostructures formed under shear might be akin to crystalline lamellae of greater thickness, compared to quiescently crystallized lamellae.

  12. Catalytic, Enantioselective Sulfenylation of Ketone-Derived Enoxysilanes

    PubMed Central

    2015-01-01

    A catalytic, enantioselective, Lewis base-catalyzed α-sulfenylation of silyl enol ethers has been developed. To avoid acidic hydrolysis of the silyl enol ether substrates, a sulfenylating agent that did not require additional Brønsted acid activation, namely N-phenylthiosaccharin, was developed. Three classes of Lewis bases—tertiary amines, sulfides, and selenophosphoramides—were identified as active catalysts for the α-sulfenylation reaction. Among a wide variety of chiral Lewis bases in all three classes, only chiral selenophosphoramides afforded α-phenylthio ketones in generally high yield and with good enantioselectivity. The selectivity of the reaction does not depend on the size of the silyl group but is highly sensitive to the double bond geometry and the bulk of the substituents on the double bond. The most selective substrates are those containing a geminal bulky substituent on the enoxysilane. Computational analysis revealed that the enantioselectivity arises from an intriguing interplay among sterically guided approach, distortion energy, and orbital interactions. PMID:25192220

  13. Metabolism of alkenes and ketones by Candida maltosa and related yeasts

    PubMed Central

    2014-01-01

    Knowledge is scarce about the degradation of ketones in yeasts. For bacteria a subterminal degradation of alkanes to ketones and their further metabolization has been described which always involved Baeyer-Villiger monooxygenases (BVMOs). In addition, the question has to be clarified whether alkenes are converted to ketones, in particular for the oil degrading yeast Candida maltosa little is known. In this study we show the degradation of the aliphatic ketone dodecane-2-one by Candida maltosa and the related yeasts Candida tropicalis, Candida catenulata and Candida albicans as well as Trichosporon asahii and Yarrowia lipolytica. One pathway is initiated by the formation of decyl acetate, resulting from a Baeyer-Villiger-oxidation of this ketone. Beyond this, an initial reduction to dodecane-2-ol by a keto reductase was clearly shown. In addition, two different ways to metabolize dodec-1-ene were proposed. One involved the formation of dodecane-2-one and the other one a conversion leading to carboxylic and dicarboxylic acids. Furthermore the induction of ketone degrading enzymes by dodecane-2-one and dodec-1-ene was shown. Interestingly, with dodecane no subterminal degradation products were detected and it did not induce any enzymes to convert dodecane-2-one. PMID:25309846

  14. Skeletal muscle PGC-1α modulates systemic ketone body homeostasis and ameliorates diabetic hyperketonemia in mice

    PubMed Central

    Svensson, Kristoffer; Albert, Verena; Cardel, Bettina; Salatino, Silvia; Handschin, Christoph

    2016-01-01

    Ketone bodies are crucial energy substrates during states of low carbohydrate availability. However, an aberrant regulation of ketone body homeostasis can lead to complications such as diabetic ketoacidosis. Exercise and diabetes affect systemic ketone body homeostasis, but the regulation of ketone body metabolism is still enigmatic. Using mice with either a knockout or overexpression of the peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) in skeletal muscle, we show that PGC-1α regulates ketolytic gene transcription in muscle. Furthermore, ketone body homeostasis of these mice was investigated during fasting, exercise, ketogenic diet feeding and after streptozotocin injection. In response to these ketogenic stimuli, we show that modulation of PGC-1α levels in muscle affects systemic ketone body homeostasis. Moreover, our data demonstrate that skeletal muscle PGC-1α is necessary for the enhanced ketolytic capacity in response to exercise training and overexpression of PGC-1α in muscle enhances systemic ketolytic capacity and is sufficient to ameliorate diabetic hyperketonemia in mice. Using cultured myotubes, we also show that the transcription factor estrogen related receptor α (ERRα) is a partner of PGC-1α in the regulation of ketolytic gene transcription. Collectively, these results demonstrate a central role of skeletal muscle PGC-1α in the transcriptional regulation of systemic ketolytic capacity. PMID:26849960

  15. Studies on the interaction between ethanol and two industrial solvents (methyl isobutyl ketone) in mice

    SciTech Connect

    Granvil, C.P.; Sharkawi, M.; Plaa, G.L. )

    1991-03-11

    Methyl n-butyl ketone (MnBK) and methyl isobutyl ketone (MiBK) prolong the duration of ethanol-induced loss of righting reflex (EILRR) in mice. MnBK was almost twice as potent in this regard. To explain this difference, the metabolism of both ketones was studied in male CD-1 mice using GC. MiBK was converted to 4-methyl-2-pentanol (4MPOL) and 4-hydroxy methyl isobutyl ketone (HMP). MnBK metabolites were 2-hexanol (2HOL) and 2,5-hexanedione (2,5HD). The effects of both ketones and metabolites on EILRR and ethanol (E) elimination were studied in mice. The ketones and their metabolites were dissolved in corn oil and injected intraperitoneally 30 min before E 4g/kg for EILRR and 2g/kg for E elimination. In the following doses: MnBK, 5; MiBK, 5; 2HOL, 2.5; 4MPOL, 2.5; and HMP 2.5, significantly prolonged EILRR. Concentrations of E in blood and brain upon return of the righting reflex were similar in solvent-treated and control animals. The mean elimination rate of E was slower in groups given MnBK or 2HOL than in control animals. No change in E elimination was observed with MiBK, HMP, 4MPOL, or 2, 5HD.

  16. Characterization and application of sodium di(2-ethylhexyl) sulfosuccinate and sodium di(2-ethylhexyl) phosphate surfactants as pseudostationary phases in micellar electrokinetic chromatography.

    PubMed

    Akbay, Cevdet; Wilmot, Nathan; Agbaria, Rezik A; Warner, Isiah M

    2004-12-17

    Sodium di(2-ethylhexyl) sulfosuccinate (DOSS) and sodium di(2-ethylhexyl) phosphate (NaDEHP) surfactants, with double alkyl chains and negatively charged headgroups, were characterized using fluorescence quenching, densitometry, and tensiometry techniques to determine their aggregation number, partial specific volume, and critical aggregation concentration. These two surfactants were then applied as pseudostationary phases in micellar electrokinetic chromatography (MEKC) for separations of alkyl phenyl ketones. The aggregation number of NaDEHP was found to be more than two-fold higher than that of DOSS. The partial specific volumes of NaDEHP and DOSS were found to be 0.9003 and 0.8371 mL/g, respectively. The critical aggregation concentrations are 5.12 and 1.80 mM for NaDEHP and DOSS, respectively. The DOSS surfactant provided a wider separation window and had a greater hydrophobic environment than the NaDEHP surfactant under the MEKC experimental conditions studied. PMID:15633750

  17. Cereal beta-glucans

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cereal beta-glucans occur predominantly in oats and barley, but can be found in other cereals. Beta-glucan structure is a mixture of single beta-1,3-linkages and consecutive beta-1,4-linkages, and cellotriosyl and cellotetraosyl units typically make up 90-95% of entire molecule. Lichenase can hydr...

  18. [2,4-13 C2 ]-beta-Hydroxybutyrate metabolism in human brain.

    PubMed

    Pan, Jullie W; de Graaf, Robin A; Petersen, Kitt F; Shulman, Gerald I; Hetherington, Hoby P; Rothman, Douglas L

    2002-07-01

    Infusions of [2,4-13C2]-beta-hydroxybutyrate and 1H-13C polarization transfer spectroscopy were used in normal human subjects to detect the entry and metabolism of beta-hydroxybutyrate in the brain. During the 2-hour infusion study, 13C label was detectable in the beta-hydroxybutyrate resonance positions and in the amino acid pools of glutamate, glutamine, and aspartate. With a plasma concentration of 2.25 +/- 0.24 mmol/L (four volunteers), the apparent tissue beta-hydroxybutyrate concentration reached 0.18 +/- 0.06 mmol/L during the last 20 minutes of the study. The relative fractional enrichment of 13C-4-glutamate labeling was 6.78 +/- 1.71%, whereas 13C-4-glutamine was 5.68 +/- 1.84%. Steady-state modeling of the 13C label distribution in glutamate and glutamine suggests that, under these conditions, the consumption of the beta-hydroxybutyrate is predominantly neuronal, used at a rate of 0.032 +/- 0.009 mmol. kg-1. min-1, and accounts for 6.4 +/- 1.6% of total acetyl coenzyme A oxidation. These results are consistent with minimal accumulation of cerebral ketones with rapid utilization, implying blood-brain barrier control of ketone oxidation in the nonfasted adult human brain. PMID:12142574

  19. The Stereoselective Reductions of Ketones to the Most Thermodynamically Stable Alcohols Using Lithium and Hydrated Salts of Common Transition Metals.

    PubMed

    Kennedy, Nicole; Cohen, Theodore

    2015-08-21

    A simple method is presented for the highly stereoselective reductions of ketones to the most thermodynamically stable alcohols. In this procedure, the ketone is treated with lithium dispersion and either FeCl2·4H2O or CuCl2·2H2O in THF at room temperature. This protocol is applied to a large number and variety of ketones and is both more convenient and efficient than those commonly reported for the diastereoselective reduction of five- and six-membered cyclic ketones. PMID:26226182

  20. Palladium/N-heterocyclic carbene catalysed regio and diastereoselective reaction of ketones with allyl reagents via inner-sphere mechanism

    DOE PAGESBeta

    Bai, Da -Chang; Yu, Fei -Le; Wang, Wan -Ying; Chen, Di; Li, Hao; Liu, Qing -Rong; Ding, Chang -Hua; Chen, Bo; Hou, Xue -Long

    2016-06-10

    The palladium-catalysed allylic substitution reaction is one of the most important reactions in transition-metal catalysis and has been well-studied in the past decades. Most of the reactions proceed through an outer-sphere mechanism, affording linear products when monosubstituted allyl reagents are used. Here, we report an efficient Palladium-catalysed protocol for reactions of beta-substituted ketones with monosubstituted allyl substrates, simply by using N-heterocyclic carbene as ligand, leading to branched products with up to three contiguous stereocentres in a (syn, anti)-mode with excellent regio and diastereoselectivities. The scope of the protocol in organic synthesis has been examined preliminarily. As a result, mechanistic studiesmore » by both experiments and density functional theory ( DFT) calculations reveal that the reaction proceeds via an inner-sphere mechanism-nucleophilic attack of enolate oxygen on Palladium followed by C-C bond-forming [3,3']-reductive elimination.« less

  1. Electronic Interactions of Michler's Ketone with DNA Bases in Synthetic Hairpins.

    PubMed

    Jalilov, Almaz S; Young, Ryan M; Eaton, Samuel W; Wasielewski, Michael R; Lewis, Frederick D

    2015-01-01

    The mechanism and dynamics of photoinduced electron transfer in two families of DNA hairpins possessing Michler's ketone linkers have been investigated by means of steady state and time-resolved transient absorption and emission spectroscopies. The excited state behavior of the diol linker employed in hairpin synthesis is similar to that of Michler's ketone in methanol solution. Hairpins possessing only a Michler's ketone linker undergo fast singlet state charge separation and charge recombination with an adjacent purine base, attributed to well-stacked ground state conformations, and intersystem crossing to the triplet state, attributed to poorly stacked ground state conformations. The failure of the triplet to undergo electron transfer reactions on the 7 ns time scale of our measurements is attributed to the low triplet energy and reduction potential of the twisted triplet state. Hairpins possessing both a Michler's ketone linker and a perylenediimide base surrogate separated by four base pairs undergo photoinduced hole transport from the diimide to Michler's ketone upon excitation of the diimide. The efficiency of hole transport is dependent upon the sequence of the intervening purine bases. PMID:25296568

  2. Presence and potential significance of aromatic-ketone groups in aquatic humic substances

    USGS Publications Warehouse

    Leenheer, J.A.; Wilson, M.A.; Malcolm, R.L.

    1987-01-01

    Aquatic humic- and fulvic-acid standards of the International Humic Substances Society were characterized, with emphasis on carbonyl-group nature and content, by carbon-13 nuclear-magnetic-resonance spectroscopy, proton nuclear-magnetic-resonance spectroscopy, and infrared spectroscopy. After comparing spectral results of underivatized humic and fulvic acids with spectral results of chemically modified derivatives, that allow improved observation of the carbonyl group, the data clearly indicated that aromatic ketone groups comprised the majority of the carbonyl-group content. About one ketone group per monocyclic aromatic ring was determined for both humic and fulvic acids. Aromatic-ketone groups were hypothesized to form by photolytic rearrangements and oxidation of phenolic ester and hydrocarbon precursors; these groups have potential significance regarding haloform formation in water, reactivity resulting from active hydrogen of the methyl and methylene adjacent to the ketone groups, and formation of hemiketal and lactol structures. Aromatic-ketone groups also may be the point of attachment between aliphatic and aromatic moieties of aquatic humic-substance structure. ?? 1987.

  3. Low dielectric fluorinated poly(phenylene ether ketone) film and coating

    NASA Technical Reports Server (NTRS)

    Cassidy, Patrick E. (Inventor); Tullos, Gordon L. (Inventor); St.clair, Anne K. (Inventor)

    1990-01-01

    The present invention relates to film and coating materials prepared from novel fluorinated poly(phenylene ether ketones). A fluorinated poly(phenylene ether ketone) is prepared by reacting a bisphenol with 1,1,1,3,3,3 hexafluoro-2,2-bis 4-(4-halobenzoyl) phenyl propane (wherein halo is fluoro or chloro), which is a novel monomer formed as the reaction product of halobenzene (wherein halo is fluoro or chloro) and 1,1,1,3,3,3 hexafluoro-2,2-bis (p-chloro formyl phenyl) propane. Especially beneficial results of this invention are that films and coating materials prepared from the novel fluorinated poly(phenylene ether ketone) are essentially optically transparent/colorless and have a lower dielectric constant than otherwise comparable, commercially available poly(phenylene ether ketones). Moreover, unlike the otherwise comparable commercially available materials, the novel fluorinated poly(phenylene ether ketones) of the present invention can be solution cast or sprayed to produce the films and coatings. Furthermore, the long term thermal stability of the polymers of the present invention is superior to that of the commercially available materials.

  4. Bioconversion to Raspberry Ketone is Achieved by Several Non-related Plant Cell Cultures

    PubMed Central

    Häkkinen, Suvi T.; Seppänen-Laakso, Tuulikki; Oksman-Caldentey, Kirsi-Marja; Rischer, Heiko

    2015-01-01

    Bioconversion, i.e., the use of biological systems to perform chemical changes in synthetic or natural compounds in mild conditions, is an attractive tool for the production of novel active or high-value compounds. Plant cells exhibit a vast biochemical potential, being able to transform a range of substances, including pharmaceutical ingredients and industrial by-products, via enzymatic processes. The use of plant cell cultures offers possibilities for contained and optimized production processes which can be applied in industrial scale. Raspberry ketone [4-(4-hydroxyphenyl)butan-2-one] is among the most interesting natural flavor compounds, due to its high demand and significant market value. The biosynthesis of this industrially relevant flavor compound is relatively well characterized, involving the condensation of 4-coumaryl-CoA and malonyl-CoA by Type III polyketide synthase to form a diketide, and the subsequent reduction catalyzed by an NADPH-dependent reductase. Raspberry ketone has been successfully produced by bioconversion using different hosts and precursors to establish more efficient and economical processes. In this work, we studied the effect of overexpressed RiZS1 in tobacco on precursor bioconversion to raspberry ketone. In addition, various wild type plant cell cultures were studied for their capacity to carry out the bioconversion to raspberry ketone using either 4-hydroxybenzalacetone or betuligenol as a substrate. Apparently plant cells possess rather widely distributed reductase activity capable of performing the bioconversion to raspberry ketone using cheap and readily available precursors. PMID:26635853

  5. Photolysis study of fluorinated ketones under natural sunlight conditions.

    PubMed

    Díaz-de-Mera, Yolanda; Aranda, Alfonso; Notario, Alberto; Rodríguez, Ana; Rodríguez, Diana; Bravo, Iván

    2015-09-21

    UV-visible absorption cross-sections are reported for CF3C(O)CH3, CF3C(O)CH2CH3, and CH3CH2C(O)CH(CH3)2. The photolysis rate constants of CF3C(O)CH3, CF3C(O)CH2CH3, and CF3CF2C(O)CF(CF3)2 were measured from smog-chamber experiments carried out in a 400 L Teflon-bag reactor under sunlight irradiation. Actinic radiation profiles from the "Tropospheric Ultraviolet and Visible Radiation Model" were used to obtain quantum efficiencies of photolysis: 0.34 ± 0.08, 0.24 ± 0.06, and (4.4 ± 0.6) × 10(-2) for CF3C(O)CH3, CF3C(O)CH2CH3, and CF3CF2C(O)CF(CF3)2, respectively. These values correspond to wavelength ranges of 295-345 nm (for CF3C(O)CH3 and CF3C(O)CH2CH3) and 295-360 nm (for CF3CF2C(O)CF(CF3)2). The photolysis rate constants change significantly with the seasons, with the yearly averages being (2.3 ± 0.7) × 10(-6), (1.8 ± 0.6) × 10(-6), and (2.1 ± 0.8) × 10(-6) s(-1) for CF3C(O)CH3, CF3C(O)CH2CH3, and CF3CF2C(O)CF(CF3)2, respectively. Photolysis processes are fast and responsible for the short gas-phase lifetimes of the studied ketones, which are 5.1 ± 2.2, 6.5 ± 2.5 and 5.5 ± 1.5 days. The radiative forcing efficiencies are provided to assess the contribution of emissions of these gases to climate change. As a result of the short atmospheric lifetimes, their global warming potentials are negligible. Theoretical calculations involving ground and excited states justify the higher photolysis quantum efficiencies of CF3C(O)CH3 and CF3C(O)CH2CH3 compared to CF3CF2C(O)CF(CF3)2, which shows increased photolysis rate constants in the absence of O2. PMID:26270890

  6. Diplogelasinospora grovesii IMI 171018 immobilized in polyurethane foam. An efficient biocatalyst for stereoselective reduction of ketones.

    PubMed

    Quezada, M A; Carballeira, J D; Sinisterra, J V

    2012-05-01

    Diplogelasinospora grovesii has been reported as a very active biocatalyst in the reduction of ketones. Along the text, the properties of this filamentous fungus as an immobilized catalyst are described. For this purpose, several immobilization supports as agar and polyurethane foam were tested. Experimental assays were also performed to test different co-substrates for the regeneration of the required enzyme cofactor. The fungus immobilized in polyurethane foam lead to the most stable and active catalyst. This derivative, using i-PrOH as co-substrate, could be reused at least 18 times without appreciable activity loss (>90% activity remains). Kinetic runs experiments shown that the reduction of cyclohexanone, selected as model substrate, followed a pseudo-first kinetic order and that the rate controlling step was the mass transfer through the cell wall. The deactivation kinetic constants were also determined. The reduction of different chiral ketones showed that the ketone reductase activity followed the Prelog's rule. PMID:22424921

  7. Carbon-Carbon Bond Formation and Hydrogen Production in the Ketonization of Aldehydes.

    PubMed

    Orozco, Lina M; Renz, Michael; Corma, Avelino

    2016-09-01

    Aldehydes possess relatively high chemical energy, which is the driving force for disproportionation reactions such as Cannizzaro and Tishchenko reactions. Generally, this energy is wasted if aldehydes are transformed into carboxylic acids with a sacrificial oxidant. Here, we describe a cascade reaction in which the surplus energy of the transformation is liberated as molecular hydrogen for the oxidation of heptanal to heptanoic acid by water, and the carboxylic acid is transformed into potentially industrially relevant symmetrical ketones by ketonic decarboxylation. The cascade reaction is catalyzed by monoclinic zirconium oxide (m-ZrO2 ). The reaction mechanism has been studied through cross-coupling experiments between different aldehydes and acids, and the final symmetrical ketones are formed by a reaction pathway that involves the previously formed carboxylic acids. Isotopic studies indicate that the carboxylic acid can be formed by a hydride shift from the adsorbed aldehyde on the metal oxide surface in the absence of noble metals. PMID:27539722

  8. C-Alkylation of Ketones and Related Compounds by Alcohols: Transition-Metal-Catalyzed Dehydrogenation.

    PubMed

    Huang, Fei; Liu, Zhuqing; Yu, Zhengkun

    2016-01-18

    Transition-metal-catalyzed C-alkylation of ketones and secondary alcohols, with alcohols, avoids use of organometallic or environmentally unfriendly alkylating agents by means of borrowing hydrogen (BH) or hydrogen autotransfer (HA) activation of the alcohol substrates. Water is formed as the only by-product, thus making the BH process atom-economical and environmentally benign. Diverse homogeneous and heterogeneous transition-metal catalysts, ketones, and alcohols can be used for this transformation, thus rendering the BH process promising for replacing those procedures that use traditional alkylating agents. This Minireview summarizes the advances during the last five years in transition-metal-catalyzed BH α-alkylation of ketones, and β-alkylation of secondary alcohols with alcohols. A discussion on the application of the BH strategy for C-C bond formation is included. PMID:26639633

  9. Enzymatic Chemoselective Aldehyde-Ketone Cross-Couplings through the Polarity Reversal of Methylacetoin.

    PubMed

    Bernacchia, Giovanni; Bortolini, Olga; De Bastiani, Morena; Lerin, Lindomar Alberto; Loschonsky, Sabrina; Massi, Alessandro; Müller, Michael; Giovannini, Pier Paolo

    2015-06-01

    The thiamine diphosphate (ThDP) dependent enzyme acetoin:dichlorophenolindophenol oxidoreductase (Ao:DCPIP OR) from Bacillus licheniformis was cloned and overexpressed in Escherichia coli. The recombinant enzyme shared close similarities with the acetylacetoin synthase (AAS) partially purified from Bacillus licheniformis suggesting that they could be the same enzyme. The product scope of the recombinant Ao:DCPIP OR was expanded to chiral tertiary α-hydroxy ketones through the rare aldehyde-ketone cross-carboligation reaction. Unprecedented is the use of methylacetoin as the acetyl anion donor in combination with a range of strongly to weakly activated ketones. In some cases, Ao:DCPIP OR produced the desired tertiary alcohols with stereochemistry opposite to that obtained with other ThDP-dependent enzymes. The combination of methylacetoin as acyl anion synthon and novel ThDP-dependent enzymes considerably expands the available range of C-C bond formations in asymmetric synthesis. PMID:25914187

  10. Asymmetric Catalysis with CO2 : The Direct α-Allylation of Ketones.

    PubMed

    Pupo, Gabriele; Properzi, Roberta; List, Benjamin

    2016-05-10

    Quaternary stereocenters are found in numerous bioactive molecules. The Tsuji-Trost reaction has proven to be a powerful C-C bond forming process, and, at least in principle, should be well suited to access quaternary stereocenters via the α-allylation of ketones. However, while indirect approaches are known, the direct, catalytic asymmetric α-allylation of branched ketones has been elusive until today. By combining "enol catalysis" with the use of CO2 as a formal catalyst for asymmetric catalysis, we have now developed a solution to this problem: we report a direct, highly enantioselective and highly atom-economic Tsuji-Trost allylation of branched ketones with allylic alcohol. Our reaction delivers products bearing quaternary stereocenters with high enantioselectivity and water as the sole by-product. We expect our methodology to be of utility in asymmetric catalysis and inspire the design of other highly atom-economic transformations. PMID:27071633

  11. Successful adaptation to ketosis by mice with tissue-specific deficiency of ketone body oxidation

    PubMed Central

    Cotter, David G.; Schugar, Rebecca C.; Wentz, Anna E.; André d'Avignon, D.

    2013-01-01

    During states of low carbohydrate intake, mammalian ketone body metabolism transfers energy substrates originally derived from fatty acyl chains within the liver to extrahepatic organs. We previously demonstrated that the mitochondrial enzyme coenzyme A (CoA) transferase [succinyl-CoA:3-oxoacid CoA transferase (SCOT), encoded by nuclear Oxct1] is required for oxidation of ketone bodies and that germline SCOT-knockout (KO) mice die within 48 h of birth because of hyperketonemic hypoglycemia. Here, we use novel transgenic and tissue-specific SCOT-KO mice to demonstrate that ketone bodies do not serve an obligate energetic role within highly ketolytic tissues during the ketogenic neonatal period or during starvation in the adult. Although transgene-mediated restoration of myocardial CoA transferase in germline SCOT-KO mice is insufficient to prevent lethal hyperketonemic hypoglycemia in the neonatal period, mice lacking CoA transferase selectively within neurons, cardiomyocytes, or skeletal myocytes are all viable as neonates. Like germline SCOT-KO neonatal mice, neonatal mice with neuronal CoA transferase deficiency exhibit increased cerebral glycolysis and glucose oxidation, and, while these neonatal mice exhibit modest hyperketonemia, they do not develop hypoglycemia. As adults, tissue-specific SCOT-KO mice tolerate starvation, exhibiting only modestly increased hyperketonemia. Finally, metabolic analysis of adult germline Oxct1+/− mice demonstrates that global diminution of ketone body oxidation yields hyperketonemia, but hypoglycemia emerges only during a protracted state of low carbohydrate intake. Together, these data suggest that, at the tissue level, ketone bodies are not a required energy substrate in the newborn period or during starvation, but rather that integrated ketone body metabolism mediates adaptation to ketogenic nutrient states. PMID:23233542

  12. Olfactory sensitivity and odor structure-activity relationships for aliphatic ketones in CD-1 mice.

    PubMed

    Laska, Matthias

    2014-06-01

    Using a conditioning paradigm, the olfactory sensitivity of CD-1 mice for a homologous series of aliphatic 2-ketones (2-butanone to 2-nonanone) and several of their isomeric forms was investigated. With all 11 odorants, the animals significantly discriminated concentrations as low as 0.01 ppm (parts per million) from the solvent, and with two odorants (2-octanone and 5-nonanone), the best-scoring animals even detected concentrations as low as 3 ppt (parts per trillion). Analysis of odor structure-activity relationships showed that the correlation between olfactory detection thresholds of the mice for the 2-ketones and carbon chain length can best be described as a U-shaped function with the lowest threshold values at 2-octanone. Similarly, the correlation between olfactory sensitivity and carbon chain length of symmetrical ketones (3-pentanone to 6-undecanone) can best be described as a U-shaped function. In contrast, no significant correlation was found between olfactory detection thresholds of the mice and position of the functional carbonyl group attached to a C7 backbone. A comparison between the olfactory detection thresholds obtained here with those obtained in earlier studies suggests that mice are significantly more sensitive for 2-ketones than for n-carboxylic acids of the same carbon chain length. Across-species comparisons suggest that mice are significantly more sensitive for aliphatic ketones than squirrel monkeys and pigtail macaques, whereas the ranges of human olfactory detection threshold values overlap with those of the mice with seven of the 11 ketones tested. Further comparisons suggest that odor structure-activity relationships are both substance class and species specific. PMID:24621664

  13. [Effect of phenolic ketones on ethanol fermentation and cellular lipid composition of Pichia stipitis].

    PubMed

    Yang, Jinlong; Cheng, Yichao; Zhu, Yuanyuan; Zhu, Junjun; Chen, Tingting; Xu, Yong; Yong, Qiang; Yu, Shiyuan

    2016-02-01

    Lignin degradation products are toxic to microorganisms, which is one of the bottlenecks for fuel ethanol production. We studied the effects of phenolic ketones (4-hydroxyacetophenone, 4-hydroxy-3-methoxy-acetophenone and 4-hydroxy-3,5-dimethoxy-acetophenone) derived from lignin degradation on ethanol fermentation of xylose and cellular lipid composition of Pichia stipitis NLP31. Ethanol and the cellular fatty acid of yeast were analyzed by high performance liquid chromatography (HPLC) and gas chromatography/mass spectrometry (GC/MS). Results indicate that phenolic ketones negatively affected ethanol fermentation of yeast and the lower molecular weight phenolic ketone compound was more toxic. When the concentration of 4-hydroxyacetophenone was 1.5 g/L, at fermentation of 24 h, the xylose utilization ratio, ethanol yield and ethanol concentration decreased by 42.47%, 5.30% and 9.76 g/L, respectively, compared to the control. When phenolic ketones were in the medium, the ratio of unsaturated fatty acids to saturated fatty acids (UFA/SFA) of yeast cells was improved. When 1.5 g/L of three aforementioned phenolic ketones was added to the fermentation medium, the UFA/SFA ratio of yeast cells increased to 3.03, 3.06 and 3.61, respectively, compared to 2.58 of the control, which increased cell membrane fluidity and instability. Therefore, phenolic ketones can reduce the yeast growth, increase the UFA/SFA ratio of yeast and lower ethanol productivity. Effectively reduce or remove the content of lignin degradation products is the key to improve lignocellulose biorefinery. PMID:27382768

  14. Copper-Catalyzed Reductive N-Alkylation of Amides with N-Tosylhydrazones Derived from Ketones.

    PubMed

    Xu, Peng; Qi, Fu-Ling; Han, Fu-She; Wang, Yan-Hua

    2016-07-20

    A CuI-catalyzed reductive coupling of ketone-derived N-tosylhydrazones with amides is presented. Under the optimized conditions, an array of N-tosylhydrazones derived from aryl-alkyl and diaryl ketones could couple effectively with a wide variety of (hetero)aryl as well as aliphatic amides to afford the N-alkylated amides in high yields. The method represents the very few examples for reliably accessing secondary and tertiary amides through a reductive N-alkylation protocol. PMID:27346856

  15. Nile Red Detection of Bacterial Hydrocarbons and Ketones in a High-Throughput Format

    SciTech Connect

    Pinzon, NM; Aukema, KG; Gralnick, JA; Wackett, LP

    2011-06-28

    A method for use in high-throughput screening of bacteria for the production of long-chain hydrocarbons and ketones by monitoring fluorescent light emission in the presence of Nile red is described. Nile red has previously been used to screen for polyhydroxybutyrate (PHB) and fatty acid esters, but this is the first report of screening for recombinant bacteria making hydrocarbons or ketones. The microtiter plate assay was evaluated using wild-type and recombinant strains of Shewanella oneidensis and Escherichia coli expressing the enzyme OleA, previously shown to initiate hydrocarbon biosynthesis. The strains expressing exogenous Stenotrophomonas maltophilia oleA, with increased levels of ketone production as determined by gas chromatography-mass spectrometry, were distinguished with Nile red fluorescence. Confocal microscopy images of S. oneidensis oleA-expressing strains stained with Nile red were consistent with a membrane localization of the ketones. This differed from Nile red staining of bacterial PHB or algal lipid droplets that showed intracellular inclusion bodies. These results demonstrated the applicability of Nile red in a high-throughput technique for the detection of bacterial hydrocarbons and ketones. IMPORTANCE In recent years, there has been renewed interest in advanced biofuel sources such as bacterial hydrocarbon production. Previous studies used solvent extraction of bacterial cultures followed by gas chromatography-mass spectrometry (GC-MS) to detect and quantify ketones and hydrocarbons (Beller HR, Goh EB, Keasling JD, Appl. Environ. Microbiol. 76: 1212-1223, 2010; Sukovich DJ, Seffernick JL, Richman JE, Gralnick JA, Wackett LP, Appl. Environ. Microbiol. 76: 3850-3862, 2010). While these analyses are powerful and accurate, their labor-intensive nature makes them intractable to high-throughput screening; therefore, methods for rapid identification of bacterial strains that are overproducing hydrocarbons are needed. The use of high

  16. Copper-catalyzed aerobic oxidative coupling: From ketone and diamine to pyrazine

    PubMed Central

    Wu, Kun; Huang, Zhiliang; Qi, Xiaotian; Li, Yingzi; Zhang, Guanghui; Liu, Chao; Yi, Hong; Meng, Lingkui; Bunel, Emilio E.; Miller, Jeffrey T.; Pao, Chih-Wen; Lee, Jyh-Fu; Lan, Yu; Lei, Aiwen

    2015-01-01

    Copper-catalyzed aerobic oxidative C–H/N–H coupling between simple ketones and diamines was developed toward the synthesis of a variety of pyrazines. Various substituted ketones were compatible for this transformation. Preliminary mechanistic investigations indicated that radical species were involved. X-ray absorption fine structure experiments elucidated that the Cu(II) species 5 coordinated by two N atoms at a distance of 2.04 Å and two O atoms at a shorter distance of 1.98 Å was a reactive one for this aerobic oxidative coupling reaction. Density functional theory calculations suggested that the intramolecular coupling of cationic radicals was favorable in this transformation. PMID:26601302

  17. Iron-, Cobalt-, and Nickel-Catalyzed Asymmetric Transfer Hydrogenation and Asymmetric Hydrogenation of Ketones.

    PubMed

    Li, Yan-Yun; Yu, Shen-Luan; Shen, Wei-Yi; Gao, Jing-Xing

    2015-09-15

    Chiral alcohols are important building blocks in the pharmaceutical and fine chemical industries. The enantioselective reduction of prochiral ketones catalyzed by transition metal complexes, especially asymmetric transfer hydrogenation (ATH) and asymmetric hydrogenation (AH), is one of the most efficient and practical methods for producing chiral alcohols. In both academic laboratories and industrial operations, catalysts based on noble metals such as ruthenium, rhodium, and iridium dominated the asymmetric reduction of ketones. However, the limited availability, high price, and toxicity of these critical metals demand their replacement with abundant, nonprecious, and biocommon metals. In this respect, the reactions catalyzed by first-row transition metals, which are more abundant and benign, have attracted more and more attention. As one of the most abundant metals on earth, iron is inexpensive, environmentally benign, and of low toxicity, and as such it is a fascinating alternative to the precious metals for catalysis and sustainable chemical manufacturing. However, iron catalysts have been undeveloped compared to other transition metals. Compared with the examples of iron-catalyzed asymmetric reduction, cobalt- and nickel-catalyzed ATH and AH of ketones are even seldom reported. In early 2004, we reported the first ATH of ketones with catalysts generated in situ from iron cluster complex and chiral PNNP ligand. Since then, we have devoted ourselves to the development of ATH and AH of ketones with iron, cobalt, and nickel catalysts containing novel chiral aminophosphine ligands. In our study, the iron catalyst containing chiral aminophosphine ligands, which are expected to control the stereochemistry at the metal atom, restrict the number of possible diastereoisomers, and effectively transfer chiral information, are successful catalysts for enantioselective reduction of ketones. Among these novel chiral aminophosphine ligands, 22-membered macrocycle P2N4

  18. One-Pot Synthesis of β-Acetamido Ketones Using Boric Acid at Room Temperature

    PubMed Central

    Karimi-Jaberi, Zahed; Mohammadi, Korosh

    2012-01-01

    β-acetamido ketones were synthesized in excellent yields through one-pot condensation reaction of aldehydes, acetophenones, acetyl chloride, and acetonitrile in the presence of boric acid as a solid heterogeneous catalyst at room temperature. It is the first successful report of boric acid that has been used as solid acid catalyst for the preparation of β-acetamido ketones. The remarkable advantages offered by this method are green catalyst, mild reaction conditions, simple procedure, short reaction times, and good-to-excellent yields of products. PMID:22666168

  19. beta-Hexachlorocyclohexane (beta-HCH)

    Integrated Risk Information System (IRIS)

    beta - Hexachlorocyclohexane ( beta - HCH ) ; CASRN 319 - 85 - 7 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Asses

  20. Decarboxylative Csp(3)-Csp(3) coupling for benzylation of unstable ketone enolates: synthesis of p-(acylethyl)phenols.

    PubMed

    Wang, Sasa; Chen, Xinzheng; Ao, Qiaoqiao; Wang, Huifei; Zhai, Hongbin

    2016-08-01

    A new decarboxylative Csp(3)-Csp(3) coupling approach for the benzylation of ketone enolates has been developed. A variety of raspberry ketone derivatives were conveniently synthesized in good to excellent yields under mild conditions. A crossover reaction shed light on the mechanism of this tandem reaction. PMID:27378390

  1. Differential EI Fragmentation Pathways for Peracetylated C-Glycoside Ketones as a Consequence of Bicyclic Ketal Ring Structures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Several C-glycoside ketones and peracetylated C-glycoside ketones have been synthesized from 13 structurally-diverse aldoses sugars (including isotope labeled [1-**13C]Glc, [U-**13C]Glc, and [6,6’-**2H2]Glc) via an aqueous-based Knoevanagel condensation with aliphatic 1,3-diketones. Sodium adduct m...

  2. Ketonization of Model Pyrolysis Oil Solutions in a Plug Flow Reactor over a Composite Oxide of Fe, Ce, and Al

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The stabilization and upgrading of pyrolysis oil requires the neutralization of the acidic components of the oil. The conversion of small organic acids, particularly acetic acid, to ketones is one approach to addressing the instability of the oils caused by low pH. In the ketonization reaction, acet...

  3. Osservatorio Astronomico di Roma

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    The Osservatorio Astronomico di Roma is a non-profit institute dedicated to astrophysical research. It was founded in the early nineteenth century, and moved to its present residence, the ancient Villa Mellini, not far from St Peter's Cathedral, in 1935....

  4. Monitoring surface processes during heterogeneous asymmetric hydrogenation of ketones on a chirally modified platinum catalyst by operando spectroscopy.

    PubMed

    Meemken, Fabian; Hungerbühler, Konrad; Baiker, Alfons

    2014-08-11

    Surface processes occurring at the catalytic chiral surface of a cinchona-modified Pt catalyst during the asymmetric hydrogenation of activated ketones have been monitored for the first time using operando ATR-IR spectroscopy. Fundamental information about this catalytic system could be gained, including the chiral modification process of the catalyst, the surface interaction of reactant ketone with preadsorbed chiral modifier, the role of hydrogen as well as the influence of the product enantiomers in the catalytic cycle. The formation of a diastereomeric transient surface complex between ketone and chiral modifier was found to be related to the ketone consumption. Among the studied activated ketones, a correlation between stereoselection and the strength of the intermolecular hydrogen bond was identified. Dissociated hydrogen from the catalytic surface is found to play a crucial role in the formation of the diastereomeric surface complex. PMID:24777839

  5. RuHCl(CO)(PPh3)3-catalyzed α-alkylation of ketones with primary alcohols.

    PubMed

    Kuwahara, Takashi; Fukuyama, Takahide; Ryu, Ilhyong

    2012-09-21

    The α-alkylation reaction of ketones with primary alcohols to give α-alkylated ketones was achieved using RuHCl(CO)(PPh(3))(3) as a catalyst in the presence of Cs(2)CO(3) as a base. This reaction proceeds via an aldol condensation of ketones with aldehydes, formed via transfer dehydrogenation of alcohols, to give α,β-unsaturated ketones, which then undergo transfer hydrogenation with primary alcohols to give α-alkylated ketones and aldehydes, the latter of which participate in the next catalytic cycle. While the reaction of aliphatic primary alcohols was sluggish compared with that of benzylic alcohols, a catalytic amount of 1,10-phenanthroline was found to promote the alkylation dramatically. PMID:22931460

  6. Gold-Catalyzed Oxidation/C-H Functionalization of Ynones: Efficient and Rapid Access to Functionalized Polycyclic Salicyl Ketones.

    PubMed

    Ji, Kegong; Yang, Fang; Gao, Shiyue; Tang, Jiangjiang; Gao, Jinming

    2016-07-11

    An efficient strategy to construct salicyl ketones through gold-catalyzed oxidation/C-H functionalization of ynones is reported. A variety of functionalized salicyl ketones are readily accessed by utilizing this non-diazo approach, thus providing a viable alternative to synthetically useful salicyl ketones with a yield up to 98 %. The α-oxo gold carbenes generated in situ through gold-catalyzed oxidation of ynones can be trapped effectively by internal aryl and heteroaromatic groups. Electronic and steric effects were also investigated in this reaction. The anticancer activity of one salicyl ketone analogue was investigated and its cytotoxicity assays against the PC-3 prostate cancer cell line and SKOV-3 human ovarian carcinoma cell line yield IC50 were 0.81±0.05 and 0.87±0.15 μm, respectively, demonstrating that salicyl ketone analogues showed good anticancer activity. PMID:27276524

  7. One-Pot Ketone Synthesis with Alkylzinc Halides Prepared from Alkyl Halides via a Single Electron Transfer (SET) Process: New Extension of Fukuyama Ketone Synthesis.

    PubMed

    Lee, Jung Hwa; Kishi, Yoshito

    2016-06-01

    One-pot ketone synthesis has been developed with in situ activation of alkyl halides to alkylzinc halides in the presence of thioesters and Pd-catalyst. The new method provides us with a reliable option for a coupling at a late stage in a convergent synthesis of complex molecules, with use of a near 1:1 molar ratio of coupling partners. First, two facile, orthogonal methods have been developed for preparation of alkylzinc halides: (1) direct insertion of zinc dust to 1°- and 2°-alkyl halides in the presence of LiI in DMI and (2) early transition-metal assisted activation of alkyl halides via a single electron transfer (SET) process. CrCl2 has been found as an unprecedented, inevitable mediator for preparation of alkylzinc halides from alkyl halides, where CrCl2 likely functions to trap R·, generated via a SET process, and transfer it to Zn(II) to form RZnX. In addition to a commonly used CoPc, a new radical initiator NbCpCl4 has been discovered through the study. Second, with use of the two orthogonal methods, three sets of coupling conditions have been developed to complete one-pot ketone synthesis, with Condition A (Pd2dba3, PR3, Zn, LiI, TESCl, DMI), Condition B (A + CrCl2), and Condition C (B + NbCpCl4 or CoPc) being useful for simple linear and α-substituted substrates, simple linear and β-substituted substrates, and complex substrates, respectively. Condition C is applicable to the broadest range of substrates. Overall, one-pot ketone synthesis gives excellent yields, with good functional group tolerance. Controlled formation of alkylzinc halides by a combination of CrCl2 and NbCpCl4 or CoPc is crucial for its application to complex substrates. Interestingly, one-pot ketone synthesis does not suffer from the chemical instability due to the inevitable radical pathway(s), for example a 1,5-H shift. Notably, even with the increase in molecular size, no significant decrease in coupling efficiency has been noticed. To illustrate the synthetic value at a late

  8. Optimization of a series of potent and selective ketone histone deacetylase inhibitors.

    PubMed

    Pescatore, Giovanna; Kinzel, Olaf; Attenni, Barbara; Cecchetti, Ottavia; Fiore, Fabrizio; Fonsi, Massimiliano; Rowley, Michael; Schultz-Fademrecht, Carsten; Serafini, Sergio; Steinkühler, Christian; Jones, Philip

    2008-10-15

    Histone deacetylase (HDAC) inhibitors offer a promising strategy for cancer therapy and the first generation HDAC inhibitors are currently in the clinic. Herein we describe the optimization of a series of ketone small molecule HDAC inhibitors leading to potent and selective class I HDAC inhibitors with good dog PK. PMID:18809328

  9. Synthesis of 2-Benzylphenyl Ketones by Aryne Insertion into Unactivated C-C Bonds.

    PubMed

    Rao, Bin; Tang, Jinghua; Zeng, Xiaoming

    2016-04-01

    A transition-metal-free procedure to access to functionalized 2-benzylphenyl ketones is described by direct insertion of arynes into benzylic C-C bonds. This reaction was promoted by cesium fluoride at room temperature, allowing the products to form in high selectivity and achieve good functional group tolerance. PMID:27004731

  10. Benzofuran ketone dosage-dependent rayless goldenrod (Isocoma pluriflora) toxicosis in a caprine model

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objectives of this study were to determine the dosage of benzofuran ketone compounds (tremetone, 3-hydroxytremetone, dehydrotremetone, and 3-oxyangeloyltremetone) and the duration of exposure to these compounds required to produce clinical signs and the associated pathological changes of rayles ...

  11. Ketone isosteres of 2-N-acetamidosugars as substrates for metabolic cell surface engineering

    SciTech Connect

    Hang, Howard C.; Bertozzi, Carolyn R.

    2000-08-22

    Novel chemical reactivity can be engendered on cell surfaces by the metabolic incorporation of unnatural sugars into cell surface glycoconjuagtes. 2-N-Acetamido sugars such as GalNAc and GlcNAc are abundant components of cell surface glycoconjugates, and hence attractive targets for metabolic cell surface engineering. Here we report (1) the synthesis of isosteric analogs bearing a ketone group in place of the N-acetamido group, and (2) evaluation of their metabolic incorporation into mammalian cell surface glycans. A ketone isostere of GalNAc was metabolized by CHO cells through the salvage pathway and delivered to O-linked glycoproteins on the cell surface. Its residence at the core position of O-linked glycans is suggested by studies with a-benzyl GalNAc, an inhibitor of O-linked oligosaccharide extension. A mutant CHO cell line lacking endogenous UDP-GalNAc demonstrated enhanced metabolism of the GalNAc analog, suggesting that competition with native intermediates might limits enzymatic transformation in mammalian cells. A ketone isostere of GlcNAc could not be detected on CHO or human cell surfaces after incubation. Thus, the enzymes in the GlcNAc salvage pathway might be less permissive of unnatural substrates than those comprising the GalNAc salvage pathway. Alternatively, high levels of endogenous GlcNAc derivatives might compete with the ketone isostere and prevent its incorporation into oligosaccharides.

  12. Lauric Acid Stimulates Ketone Body Production in the KT-5 Astrocyte Cell Line.

    PubMed

    Nonaka, Yudai; Takagi, Tetsuo; Inai, Makoto; Nishimura, Shuhei; Urashima, Shogo; Honda, Kazumitsu; Aoyama, Toshiaki; Terada, Shin

    2016-08-01

    Coconut oil has recently attracted considerable attention as a potential Alzheimer's disease therapy because it contains large amounts of medium-chain fatty acids (MCFAs) and its consumption is thought to stimulate hepatic ketogenesis, supplying an alternative energy source for brains with impaired glucose metabolism. In this study, we first reevaluated the responses of plasma ketone bodies to oral administration of coconut oil to rats. We found that the coconut oil-induced increase in plasma ketone body concentration was negligible and did not significantly differ from that observed after high-oleic sunflower oil administration. In contrast, the administration of coconut oil substantially increased the plasma free fatty acid concentration and lauric acid content, which is the major MCFA in coconut oil. Next, to elucidate whether lauric acid can activate ketogenesis in astrocytes with the capacity to generate ketone bodies from fatty acids, we treated the KT-5 astrocyte cell line with 50 and 100 μM lauric acid for 4 h. The lauric acid treatments increased the total ketone body concentration in the cell culture supernatant to a greater extent than oleic acid, suggesting that lauric acid can directly and potently activate ketogenesis in KT-5 astrocytes. These results suggest that coconut oil intake may improve brain health by directly activating ketogenesis in astrocytes and thereby by providing fuel to neighboring neurons. PMID:27430387

  13. Two-Carbon Homologation of Ketones to 3-Methyl Unsaturated Aldehydes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The usual scheme of two-carbon homologation of ketones to 3-methyl unsaturated aldehydes by Horner-Wadsworth-Emmons condensations with phosphonate esters, such as triethyl-2-phosphonoacetate, involves three steps. The phosphonate condensation step results in extension of the carbon chain by two carb...

  14. Effects of bioactive monoterpenic ketones on membrane organization. A langmuir film study.

    PubMed

    Mariani, María Elisa; Sánchez-Borzone, Mariela E; García, Daniel A

    2016-06-01

    The cyclic ketones, thujone and dihydrocarvone, are lipophilic components of essential oils extracted from different plants, which have proven insecticidal activity. The GABAA receptor is activated by the neurotransmitter GABA and is the action site of widely used neurotoxic pesticides. Many compounds that regulate GABAA receptor function interact with membrane lipids, causing changes in their physical properties and consequently, in the membrane dynamic characteristics that modulate receptor macromolecules. In the present study, the biophysical effects of thujone (a gabaergic reference compound) and dihydrocarvone (structurally very similar) were explored by using monomolecular films of DPPC as a model membrane system, to gain insight into membrane-drug interaction. The compression isotherms showed that both ketones expand the DPPC isotherms and increase membrane elasticity. They penetrate the monolayer but their permanence depends on the possibility of establishing molecular interactions with the film component, favored by defects present in the membrane at the phase transition. Finally, by using Brewster angle microscopy (BAM) as a complementary technique for direct visualization of the study films, we found that incorporating ketone seems to reduce molecular repulsion among phospholipid headgroups. Our results reinforce the notion that changes in membrane mechanics may be occurring in the presence of the assayed ketones, suggesting that their interaction with the receptor's surrounding membrane may modulate or affect its functionality, possibly as part of the mechanism of the bioactivity described for thujone and DHC. PMID:27174212

  15. The central role of ketones in reversible and irreversible hydrothermal organic functional group transformations

    NASA Astrophysics Data System (ADS)

    Yang, Ziming; Gould, Ian R.; Williams, Lynda B.; Hartnett, Hilairy E.; Shock, Everett L.

    2012-12-01

    Studies of hydrothermal reactions involving organic compounds suggest complex, possibly reversible, reaction pathways that link functional groups from reduced alkanes all the way to oxidized carboxylic acids. Ketones represent a critical functional group because they occupy a central position in the reaction pathway, at the point where Csbnd C bond cleavage is required for the formation of the more oxidized carboxylic acids. The mechanisms for the critical bond cleavage reactions in ketones, and how they compete with other reactions are the focus of this experimental study. We studied a model ketone, dibenzylketone (DBK), in H2O at 300 °C and 70 MPa for up to 528 h. Product analysis was performed as a function of time at low DBK conversions to reveal the primary reaction pathways. Reversible interconversion between ketone, alcohol, alkene and alkane functional groups is observed in addition to formation of radical coupling products derived from irreversible Csbnd C and Csbnd H homolytic bond cleavage. The product distributions are time-dependent but the bond cleavage products dominate. The major products that accumulate at longer reaction times are toluene and larger, dehydrogenated structures that are initially formed by radical coupling. The hydrogen atoms generated by dehydrogenation of the coupling products are predominantly consumed in the formation of toluene. Even though bond cleavage products dominate, no carboxylic acids were observed on the timescale of the reactions under the chosen experimental conditions.

  16. Microwave-Assisted Copper-Catalyzed Oxidative Cyclization of Acrylamides with Non-Activated Ketones.

    PubMed

    Zhao, Yaping; Sharma, Nandini; Sharma, Upendra K; Li, Zhenghua; Song, Gonghua; Van der Eycken, Erik V

    2016-04-18

    An operationally simple and efficient microwave-assisted protocol for the oxidative cyclization of acrylamide derivatives with non-activated ketones to generate 3,3-disubstituted oxindoles is described. The reaction proceeds by a copper-catalyzed tandem radical addition/cyclization strategy and tolerates a series of functional groups with moderate to excellent yields. PMID:26868308

  17. Poly(arylene ether ketone) carrying hyperquaternized pendants: Preparation, stability and conductivity

    NASA Astrophysics Data System (ADS)

    Shen, Kunzhi; Zhang, Zhenpeng; Zhang, Haibo; Pang, Jinhui; Jiang, Zhenhua

    2015-08-01

    A new strategy to synthesize comb-shaped poly(arylene ether ketone) ionomers with hyperquaternized pendants was detailed in this work. Poly(arylene ether ketone) with electron-rich phenyl rings on the side chain was copolymerized. These electron-rich phenyl rings which could be chloromethylated and serve as precursors to cationic sites, are introduced during monomer synthesis. After chloromethylation and quaternization on the side chain, these resulting anion exchange membranes exhibit high conductivities and good dimensional stability, which benefit from the side chain type structure. The highest chloride conductivity of 0.047 S cm-1 was observed in PAEK-QTPM-30 (IEC = 1.58 mmol g-1) and swelling ratio is 31.7% at 80 °C. The structural properties of the synthesized poly(arylene ether ketone)s were investigated by 1H NMR spectroscopy. The anion exchange membranes showed excellent thermal stability up to 200 °C under nitrogen and good chemical stability for high conductivity after treating in alkaline condition up to 30 days. These membranes were studied by IEC, water uptake, dimensional stability. The nano-phase separation from ionic aggregation was confirmed by SAXS. This work implies a viable strategy to improve the performance of anion exchange membranes.

  18. Raspberry Ketone Trifluoroacetate, a New Attractant for the Queensland Fruit Fly, Bactrocera Tryoni (Froggatt).

    PubMed

    Siderhurst, Matthew S; Park, Soo J; Buller, Caitlyn N; Jamie, Ian M; Manoukis, Nicholas C; Jang, Eric B; Taylor, Phillip W

    2016-02-01

    Queensland fruit fly, Bactrocera tryoni (Q-fly), is a major pest of horticultural crops in eastern Australia. Lures that attract male Q-fly are important for detection of incursions and outbreaks, monitoring of populations, and control by mass trapping and male annihilation. Cuelure, an analog of naturally occurring raspberry ketone, is the standard Q-fly lure, but it has limited efficacy compared with lures that are available for some other fruit flies such as methyl eugenol for B. dorsalis. Melolure is a more recently developed raspberry ketone analog that has shown better attraction than cuelure in some field studies but not in others. A novel fluorinated analog of raspberry ketone, raspberry ketone trifluoroacetate (RKTA), has been developed as a potential improvement on cuelure and melolure. RKTA placed on laboratory cages containing 2-week-old Q-flies elicited strong behavioral responses from males. Quantification of Q-fly responses in these cages, using digital images to estimate numbers of flies aggregated near different lures, showed RKTA attracted and arrested significantly more flies than did cuelure or melolure. RKTA shows good potential as a new lure for improved surveillance and control of Q-fly. PMID:26922349

  19. Novel Oxidation of Cyclosporin A: Preparation of Cyclosporin Methyl Vinyl Ketone (Cs-MVK)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cyclosporin A (CsA) was converted into cyclosporin methyl vinyl ketone (Cs-MVK) by either a biocatalytic method utilizing 1-hydroxybenzotriazole-mediated laccase oxidation or by a chemical oxidation using t-butyl hydroperoxide and potassium ­periodate as co-oxidants. Cs-MVK is a novel, versatile sy...

  20. Highly efficient and direct heterocyclization of dipyridyl ketone to N,N-bidentate ligands

    NASA Technical Reports Server (NTRS)

    Wang, Jie; Dyers, Leon Jr; Mason, Richard Jr; Amoyaw, Prince; Bu, Xiu R.

    2005-01-01

    [reaction: see text] Reaction of various aromatic aldehydes with 2,2'-dipyridyl ketone and ammonium acetate in hot acetic acid provides ready access to a series of substituted 1-pyridylimidazo[1,5-a]pyridines, a class of ligands possessing an N,N-bidentate feature, in good yields.

  1. Palladium-catalyzed dehydrogenation/oxidative cross-coupling sequence of β-heteroatom-substituted ketones.

    PubMed

    Moon, Youngtaek; Kwon, Daeil; Hong, Sungwoo

    2012-11-01

    Concise and selective: the title one-pot sequence allows formation of the enone functionality and subsequent cross-coupling. The process provides access to highly functionalized cyclic enolones and enaminones from readily accessible β-heteroatom-substituted cyclic ketones. PMID:23038616

  2. Two-Dimensional Ketone-Driven Metal-Organic Coordination on Cu(111).

    PubMed

    Della Pia, Ada; Riello, Massimo; Lawrence, James; Stassen, Daphne; Jones, Tim S; Bonifazi, Davide; De Vita, Alessandro; Costantini, Giovanni

    2016-06-01

    Two-dimensional metal-organic nanostructures based on the binding of ketone groups and metal atoms were fabricated by depositing pyrene-4,5,9,10-tetraone (PTO) molecules on a Cu(111) surface. The strongly electronegative ketone moieties bind to either copper adatoms from the substrate or codeposited iron atoms. In the former case, scanning tunnelling microscopy images reveal the development of an extended metal-organic supramolecular structure. Each copper adatom coordinates to two ketone ligands of two neighbouring PTO molecules, forming chains that are linked together into large islands through secondary van der Waals interactions. Deposition of iron atoms leads to a transformation of this assembly resulting from the substitution of the metal centres. Density functional theory calculations reveal that the driving force for the metal substitution is primarily determined by the strength of the ketone-metal bond, which is higher for Fe than for Cu. This second class of nanostructures displays a structural dependence on the rate of iron deposition. PMID:27071489

  3. Copper-catalyzed synthesis of benzocarbazoles via α-C-arylation of ketones.

    PubMed

    Xie, Ruilong; Ling, Yun; Fu, Hua

    2012-12-28

    A simple and efficient copper-catalyzed method for the synthesis of 11H-benzo[a]carbazoles has been developed. The protocol uses readily available substituted 2-(2-bromophenyl)-1H-indoles and ketones as starting materials and an inexpensive catalyst system. The corresponding 11H-benzo[a]carbazoles were obtained in moderate to excellent yields. PMID:23146998

  4. Extremely efficient hydroboration of ketones and aldehydes by copper carbene catalysis.

    PubMed

    Bagherzadeh, Sharareh; Mankad, Neal P

    2016-03-01

    A readily available copper carbene complex, (IPr)CuOtBu, catalyses the hydroboration of ketones and aldehydes even at very low catalyst loadings (0.1 mol%), in some cases with turnover frequencies exceeding 6000 h(-1). Carbonyl reduction occurs selectivitily in the presence of other reducible functional groups including alkenes, nitriles, esters, and alkyl chlorides. PMID:26871503

  5. Cardiomyocyte-specific deficiency of ketone body metabolism promotes accelerated pathological remodeling

    PubMed Central

    Schugar, Rebecca C.; Moll, Ashley R.; André d’Avignon, D.; Weinheimer, Carla J.; Kovacs, Attila; Crawford, Peter A.

    2014-01-01

    Objective Exploitation of protective metabolic pathways within injured myocardium still remains an unclarified therapeutic target in heart disease. Moreover, while the roles of altered fatty acid and glucose metabolism in the failing heart have been explored, the influence of highly dynamic and nutritionally modifiable ketone body metabolism in the regulation of myocardial substrate utilization, mitochondrial bioenergetics, reactive oxygen species (ROS) generation, and hemodynamic response to injury remains undefined. Methods Here we use mice that lack the enzyme required for terminal oxidation of ketone bodies, succinyl-CoA:3-oxoacid CoA transferase (SCOT) to determine the role of ketone body oxidation in the myocardial injury response. Tracer delivery in ex vivo perfused hearts coupled to NMR spectroscopy, in vivo high-resolution echocardiographic quantification of cardiac hemodynamics in nutritionally and surgically modified mice, and cellular and molecular measurements of energetic and oxidative stress responses are performed. Results While germline SCOT-knockout (KO) mice die in the early postnatal period, adult mice with cardiomyocyte-specific loss of SCOT (SCOT-Heart-KO) remarkably exhibit no overt metabolic abnormalities, and no differences in left ventricular mass or impairments of systolic function during periods of ketosis, including fasting and adherence to a ketogenic diet. Myocardial fatty acid oxidation is increased when ketones are delivered but cannot be oxidized. To determine the role of ketone body oxidation in the remodeling ventricle, we induced pressure overload injury by performing transverse aortic constriction (TAC) surgery in SCOT-Heart-KO and αMHC-Cre control mice. While TAC increased left ventricular mass equally in both groups, at four weeks post-TAC, myocardial ROS abundance was increased in myocardium of SCOT-Heart-KO mice, and mitochondria and myofilaments were ultrastructurally disordered. Eight weeks post-TAC, left ventricular

  6. A new bacterial dehydrogenase oxidizing the lignin model compound guaiacylglycerol beta-O-4-guaiacyl ether.

    PubMed

    Pelmont, J; Barrelle, M; Hauteville, M; Gamba, D; Romdhane, M; Dardas, A; Beguin, C

    1985-09-01

    A lignin model compound, named in short guaiagylglycerol beta-guaiacyl ether (GGE), contains the beta-0-4 ether linkage that is common in the chemical structure of lignin. A Pseudomonas sp. (GU5) had been isolated as an organism able to grow with GGE as the sole source of carbon and energy. When grown on vanillate, the bacteria contained a NAD+ -dependent dehydrogenase converting GGE to a 355 nm absorbing product. The enzyme, named GGE-dehydrogenase, was purified about 160-fold using gel permeation, ion exchange on DEAE-Sephadex, and dye-ligand affinity chromatography. The new protein was about 52 kDa in apparent size with but one polypeptide chain after denaturation and reduction. According to several criteria, the product of GGE oxidation (Km = 12 microM) was identified as the corresponding conjugated ketone at the alpha-carbon of the C3 side-chain. The secondary alcohol function in GGE was apparently the sole target of the enzyme action. However the conversion of GGE into ketone catalyzed by the enzyme was only partial, and did not exceed 50%, probably because only one of the alpha-enantiomers was susceptible to enzyme attack. In contrast the ketone, either made by organic synthesis or by enzymic oxidation of GGE, could be totally reduced back to GGE (Km = 13 microM at pH 8.4, 8 microM at neutral pH), with NADH as the reductant, as confirmed by UV absorption and NMR spectra. Other model compounds with no primary alcoholic function, ether linkage or phenolic group were also substrates for the enzyme, confirming the specificity of GGE-dehydrogenase for the alpha-carbon position. Conjugation of the alpha-ketone with an adjacent phenolic nucleus interfered strongly with equilibrium constants and redox potentials of the system according to pH, and the enzyme displayed widely different optima with pH over 9 when oxidizing GGE, below 7 when reducing the ketone. Equilibrium studies showed that the ketone/GGE potential was -0.37 volt at pH 8.7, -0.23 volt at pH 7 (30

  7. Fatty acid-induced astrocyte ketone production and the control of food intake.

    PubMed

    Le Foll, Christelle; Levin, Barry E

    2016-06-01

    Obesity and Type 2 diabetes are major worldwide public health issues today. A relationship between total fat intake and obesity has been found. In addition, the mechanisms of long-term and excessive high-fat diet (HFD) intake in the development of obesity still need to be elucidated. The ventromedial hypothalamus (VMH) is a major site involved in the regulation of glucose and energy homeostasis where "metabolic sensing neurons" integrate metabolic signals from the periphery. Among these signals, fatty acids (FA) modulate the activity of VMH neurons using the FA translocator/CD36, which plays a critical role in the regulation of energy and glucose homeostasis. During low-fat diet (LFD) intake, FA are oxidized by VMH astrocytes to fuel their ongoing metabolic needs. However, HFD intake causes VMH astrocytes to use FA to generate ketone bodies. We postulate that these astrocyte-derived ketone bodies are exported to neurons where they produce excess ATP and reactive oxygen species, which override CD36-mediated FA sensing and act as a signal to decrease short-term food intake. On a HFD, VMH astrocyte-produced ketones reduce elevated caloric intake to LFD levels after 3 days in rats genetically predisposed to resist (DR) diet-induced obesity (DIO), but not leptin-resistant DIO rats. This suggests that, while VMH ketone production on a HFD can contribute to protection from obesity, the inherent leptin resistance overrides this inhibitory action of ketone bodies on food intake. Thus, astrocytes and neurons form a tight metabolic unit that is able to monitor circulating nutrients to alter food intake and energy homeostasis. PMID:27122369

  8. Solvent extraction of N-Cyclohexyl-N-Nitrosohydroxylamine (cnha) into some organic solvents and of the Cu(II)-cnha complex into methyl isobutyl ketone.

    PubMed

    Rauret, G; Pineda, L; Ventura, M; Compaño, R

    1986-02-01

    The distribution equilibria of N-cyclohexyl-N-nitrosohydroxylamine (cnha) in the water-chloroform, water-hexane, water-methyl isobutyl ketone (MIBK) and water-isopentyl alcohol systems, and of the Cu(II)-cnha complex in the water-MIBK system have been studied. From the distribution data the dissociation and distribution constants of the reagent have been calculated; their values are pK(a) = 5.55 +/- 0.10; log K(DR) = 2.46 +/- 0.05 (chloroform), 1.76 +/- 0.11 (MIBK), 1.06 +/- 0.07 (hexane) and 1.48 +/- 0.06 (isopentyl alcohol). In the same way the values of the distribution and stability constants of the Cu(II) complex have been obtained; log K(DC) = 3.51; log beta(1) = 7.23 +/- 0.10 and log beta(2) = 12.00 +/- 0.08. For the determination of cnha in the aqueous phase saturated with MIBK, a spectrophotometric method based on the coloured complex formed by the reagent with Fe(III) has been established. Finally, an analytical method for Cu(II) by atomic-absorption spectrometry after its extraction with cnha into MIBK, is proposed. Its detection limit is 4.6 mug l ., its precision +/- 2.1% and its accuracy 97.5%. This method has been applied to the determination of the copper content in the surface water of the Congest River of Catalonia (Spain). PMID:18964050

  9. Gas-film coefficients for the volatilization of ketones from water

    USGS Publications Warehouse

    Rathbun, R.E.; Tai, D.Y.

    1986-01-01

    Volatilization is a significant process in determining the fate of many organic compounds in streams and rivers. Quantifying this process requires knowledge of the mass-transfer coefficient from water, which is a function of the gas-film and liquid-film coefficients. The gas-film coefficient can be determined by measuring the flux for the volatilization of pure organic liquids. Volatilization fluxes for acetone, 2-butanone, 2-pentanone, 3-pentanone, 4-methyl-2-pentanone, 2-heptanone, and 2-octanone were measured in the laboratory over a range of temperatures. Gas-film coefficients were then calculated from these fluxes and from vapor pressure data from the literature. An equation was developed for predicting the volatilization flux of pure liquid ketones as a function of vapor pressure and molecular weight. Large deviations were found for acetone, and these were attributed to the possibility that acetone may be hydrogen bonded. A second equation for predicting the flux as a function of molecular weight and temperature resulted in large deviations for 4methyl-2-pentanone. These deviations were attributed to the branched structure of this ketone. Four factors based on the theory of volatilization and relating the volatilization flux or rate to the vapor pressure, molecular weight, temperature, and molecular diffusion coefficient were not constant as suggested by the literature. The factors generally increased with molecular weight and with temperature. Values for acetone corresponded to ketones with a larger molecular weight, and the acetone factors showed the greatest dependence on temperature. Both of these results are characteristic of compounds that are hydrogen bonded. Relations from the literature commonly used for describing the dependence of the gas-film coefficient on molecular weight and molecular diffusion coefficient were not applicable to the ketone gas-film coefficients. The dependence on molecular weight and molecular diffusion coefficient was in

  10. Homogeneous and heterogeneous photoredox-catalyzed hydroxymethylation of ketones and keto esters: catalyst screening, chemoselectivity and dilution effects.

    PubMed

    Griesbeck, Axel G; Reckenthäler, Melissa

    2014-01-01

    The homogeneous titanium- and dye-catalyzed as well as the heterogeneous semiconductor particle-catalyzed photohydroxymethylation of ketones by methanol were investigated in order to evaluate the most active photocatalyst system. Dialkoxytitanium dichlorides are the most efficient species for chemoselective hydroxymethylation of acetophenone as well as other aromatic and aliphatic ketones. Pinacol coupling is the dominant process for semiconductor catalysis and ketone reduction dominates the Ti(OiPr)4/methanol or isopropanol systems. Application of dilution effects on the TiO2 catalysis leads to an increase in hydroxymethylation at the expense of the pinacol coupling. PMID:24991265

  11. Reductions of aldehydes and ketones with a readily available N-heterocyclic carbene borane and acetic acid

    PubMed Central

    Lamm, Vladimir; Pan, Xiangcheng

    2013-01-01

    Summary Acetic acid promotes the reduction of aldehydes and ketones by the readily available N-heterocyclic carbene borane, 1,3-dimethylimidazol-2-ylidene borane. Aldehydes are reduced over 1–24 h at room temperature with 1 equiv of acetic acid and 0.5 equiv of the NHC-borane. Ketone reductions are slower but can be accelerated by using 5 equiv of acetic acid. Aldehydes can be selectively reduced in the presence of ketones. On a small scale, products are isolated by evaporation of the reaction mixture and direct chromatography. PMID:23616812

  12. MODE OF ACTION OF ACETYLXYLAN ESTERASE FROM STREPTOMYCES LIVIDANS: A STUDY WITH DEOXY AND DEOXY-FLUORO ANALOGUES OF ACETYLATED METHYL BETA-D-XYLOPYRANOSIDE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The action of Streptomyces lividans acetylxylan esterase on methyl 2,4-di-O-acetyl- and 3,4-di-O-acetyl beta-D-xylopyranoside was compared with its action on the 2- and 3-deoxy and 2- and 3-deoxy-fluoro-analogues of the two diacetates in order to elucidate the role of the free hydroxyl group in the ...

  13. Base-promoted reactions of bridged ketones and 1,3- and 1,4-haloalkyl azides: competitive alkylation vs azidation reactions of ketone enolates.

    PubMed

    Yao, Lei; Smith, Brenton T; Aubé, Jeffrey

    2004-03-01

    The reactions of 1,3- and 1,4-haloalkyl azides with enolates of 2-norbornanone (and a ring-expanded analog) afford polycyclic 1,2,3-triazolines in good yields. The reaction occurs by the initial azidation of the ketone enolate, followed in order by triazoline formation and O-alkylation. An interesting element of this process is the preferential reaction of the alkyl azide with an enolate anion as opposed to the more familiar reaction of the alkyl halide (including Cl and I derivatives). Reactions of acyclic or monocyclic enolates generally lead to 1,2,3-triazoles but none of the alternative C-alkylation product. PMID:14987033

  14. Ca(OH)2-Catalyzed Condensation of Aldehydes with Methyl ketones in Dilute Aqueous Ethanol: A Comprehensive Access to α,β-Unsaturated Ketones

    PubMed Central

    Yu, Lei; Han, Mengting; Luan, Jie; Xu, Lin; Ding, Yuanhua; Xu, Qing

    2016-01-01

    Cheap, abundant but seldom-employed Ca(OH)2 was found to be an excellent low-loading (5–10 mol%) catalyst for Claisen-Schmidt condensation of aldehydes with methyl ketones under mild conditions. It was interesting that dilute aqueous ethanol (20 v/v%) was unexpectedly discovered to be the optimal solvent. The reaction was scalable at least to 100 mmol and calcium could be precipitated by CO2 and removed by filtration. Evaporation of solvent directly afforded the product in the excellent 96% yield with high purity, as confirmed by its 1H NMR spectrum. PMID:27443482

  15. Ca(OH)2-Catalyzed Condensation of Aldehydes with Methyl ketones in Dilute Aqueous Ethanol: A Comprehensive Access to α,β-Unsaturated Ketones

    NASA Astrophysics Data System (ADS)

    Yu, Lei; Han, Mengting; Luan, Jie; Xu, Lin; Ding, Yuanhua; Xu, Qing

    2016-07-01

    Cheap, abundant but seldom-employed Ca(OH)2 was found to be an excellent low-loading (5–10 mol%) catalyst for Claisen-Schmidt condensation of aldehydes with methyl ketones under mild conditions. It was interesting that dilute aqueous ethanol (20 v/v%) was unexpectedly discovered to be the optimal solvent. The reaction was scalable at least to 100 mmol and calcium could be precipitated by CO2 and removed by filtration. Evaporation of solvent directly afforded the product in the excellent 96% yield with high purity, as confirmed by its 1H NMR spectrum.

  16. Ca(OH)2-Catalyzed Condensation of Aldehydes with Methyl ketones in Dilute Aqueous Ethanol: A Comprehensive Access to α,β-Unsaturated Ketones.

    PubMed

    Yu, Lei; Han, Mengting; Luan, Jie; Xu, Lin; Ding, Yuanhua; Xu, Qing

    2016-01-01

    Cheap, abundant but seldom-employed Ca(OH)2 was found to be an excellent low-loading (5-10 mol%) catalyst for Claisen-Schmidt condensation of aldehydes with methyl ketones under mild conditions. It was interesting that dilute aqueous ethanol (20 v/v%) was unexpectedly discovered to be the optimal solvent. The reaction was scalable at least to 100 mmol and calcium could be precipitated by CO2 and removed by filtration. Evaporation of solvent directly afforded the product in the excellent 96% yield with high purity, as confirmed by its (1)H NMR spectrum. PMID:27443482

  17. Highly Enantioselective Epoxidation of α,β-Unsaturated Ketones Catalyzed by Rare-Earth Amides [(Me3Si)2N]3RE(μ-Cl)Li(THF)3 with Phenoxy-Functionalized Chiral Prolinols.

    PubMed

    Zeng, Chao; Yuan, Dan; Zhao, Bei; Yao, Yingming

    2015-05-01

    A simple and efficient catalytic enantioselective epoxidation of α,β-unsaturated ketones has been successfully developed, which was catalyzed by rare-earth metal amides [(Me3Si)2N]3RE(μ-Cl)Li(THF)3 (RE = Yb (1), La (2), Sm (3), Y (4), Lu (5)) in the presence of phenoxy-functionalized chiral prolinols at room temperature using tert-butylhydroperoxide (TBHP) as the oxidant. The combination of an Yb-based amide 1 and a chiral proligand (S)-2,4-di-tert-butyl-6-((2-(hydroxydiphenylmethyl)pyrrolidin-1-yl)methyl)phenol) performed very well, and both the yields and the enantiomeric excess of the chiral epoxides reached up to 99% and 99% ee. PMID:25905674

  18. The selectivity of beta-adrenoceptor antagonists at the human beta1, beta2 and beta3 adrenoceptors.

    PubMed

    Baker, Jillian G

    2005-02-01

    Beta-adrenoceptor antagonists ("beta-blockers") are one of the most widely used classes of drugs in cardiovascular medicine (hypertension, ischaemic heart disease and increasingly in heart failure) as well as in the management of anxiety, migraine and glaucoma. Where known, the mode of action in cardiovascular disease is from antagonism of endogenous catecholamine responses in the heart (mainly at beta1-adrenoceptors), while the worrisome side effects of bronchospasm result from airway beta2-adrenoceptor blockade. The aim of this study was to determine the selectivity of beta-antagonists for the human beta-adrenoceptor subtypes. (3)H-CGP 12177 whole cell-binding studies were undertaken in CHO cell lines stably expressing either the human beta1-, beta2- or the beta3-adrenoceptor in order to determine the affinity of ligands for each receptor subtype in the same cell background. In this study, the selectivity of well-known subtype-selective ligands was clearly demonstrated: thus, the selective beta1 antagonist CGP 20712A was 501-fold selective over beta2 and 4169-fold selective over beta3; the beta2-selective antagonist ICI 118551 was 550- and 661-fold selective over beta1 and beta3, respectively, and the selective beta3 compound CL 316243 was 10-fold selective over beta2 and more than 129-fold selective over beta1. Those beta2-adrenoceptor agonists used clinically for the treatment of asthma and COPD were beta2 selective: 29-, 61- and 2818-fold for salbutamol, terbutaline and salmeterol over beta1, respectively. There was little difference in the affinity of these ligands between beta1 and beta3 adrenoceptors. The clinically used beta-antagonists studied ranged from bisoprolol (14-fold beta1-selective) to timolol (26-fold beta2-selective). However, the majority showed little selectivity for the beta1- over the beta2-adrenoceptor, with many actually being more beta2-selective. This study shows that the beta1/beta2 selectivity of most clinically used beta-blockers is

  19. Effects of increased mechanical work by isolated perfused rat heart during production or uptake of ketone bodies. Assessment of mitochondrial oxidized to reduced free nicotinamide-adenine dinucleotide ratios and oxaloacetate concentrations.

    PubMed Central

    Opie, L H; Owen, P

    1975-01-01

    Metabolic effects of increased mechanical work were studied by comparing isolated pumping rat hearts perfused by the atrial-filling technique with aortic-perfused non-pumping hearts perfused by the technique of Langendorff. The initial medium usually contained glucose (11 mm) and palmitate (0.6 mm bound to 0.1 mm albumin). During increased heart work (comparing pumping with non-pumping hearts) the uptake of oxygen and glucose increased threefold, but that of free fatty acids was unchanged. Tissue contents of alpha-oxoglutarate, NH4+, malate, lactate, pyruvate and Pi rose with increased heart work, but contents of ATP, phosphocreatine and citrate fell. Ketone bodies were produced with a ratio of beta-hydroxybutyrate/acetoacetate of about 3:1 in both pumping and non-pumping hearts but with higher net production rates in non-pumping hearts. When ketone bodies were added in relatively high concentrations (total 4 mm) to a glucose (11 mm) medium the medium, ratios of beta-hydroxybutyrate/acetoacetate were not steady even after 60 min of perfusion. The validity of calculating mitochondrial free NAD+/NADH ratios from the tissue contents of the reactants of the glutamate dehydrogenase system or the beta-hydroxybutyrate dehydrogenase system is assessed. The activities of these enzymes are considerably less in the rat heart than in the rat liver, introducing reservations into the application to the heart of the principles used by Williamson et al. (1967) for calculation of mitochondrial free NAD+/NADH ratios of liver mitochondria... PMID:173281

  20. High Beta Tokamaks

    SciTech Connect

    Cowley, S.

    1998-11-14

    Perhaps the ideal tokamak would have high {beta} ({beta} {approx}> 1) and classical confinement. Such a tokamak has not been found, and we do not know if one does exist. We have searched for such a possibility, so far without success. In 1990, we obtained analytic equilibrium solutions for large aspect ratio tokamaks at {beta} {approx} {Omicron}(1) [1]. These solutions and the extension at high {beta} poloidal to finite aspect ratio [2] provided a basis for the study of high {beta} tokamaks. We have shown that these configurations can be stable to short scale MHD modes [3], and that they have reduced neoclassical transport [4]. Microinstabilities (such as the {del}T{sub i} mode) seem to be stabilized at high {beta} [5] - this is due to the large local shear [3] and the magnetic well. We have some concerns about modes associated with the compressional branch which may appear at high {beta}. Bill Dorland and Mike Kotschenreuther have studied this issue and our concerns may be unfounded. It is certainly tantalizing, especially given the lowered neoclassical transport values, that these configurations could have no microinstabilities and, one could assume, no anomalous transport. Unfortunately, while this work is encouraging, the key question for high {beta} tokamaks is the stability to large scale kink modes. The MHD {beta} limit (Troyon limit) for kink modes at large aspect ratio is problematically low. There is ample evidence from computations that the limit exists. However, it is not known if stable equilibria exist at much higher {beta}--none have been found. We have explored this question in the asymptotic high {beta} poloidal limit. Unfortunately, we are unable to find stable equilibrium and also unable to show that they don't exist. The results of these calculations will be published when a more definitive answer is found.

  1. Unusual Allylpalladium Carboxylate Complexes: Identification of the Resting State of Catalytic Enantioselective Decarboxylative Ketone Allylic Alkylation Reactions**

    PubMed Central

    Sherden, Nathaniel H.; Behenna, Douglas C.; Virgil, Scott C.

    2010-01-01

    Palladium poprocks: Hold on to your CO2! Enantioselective Pd-catalyzed decarboxylative alkylation of ketone enolates proceeds via η1-σ-allyl Pd-carboxylate complexes by slow loss of CO2. PMID:19672907

  2. Facile Access to Sterically Hindered Aryl Ketones via Carbonylative Cross-Coupling: Application to the Total Synthesis of Luteolin

    PubMed Central

    O’Keefe, B. Michael; Simmons, Nicholas

    2011-01-01

    A general and mild protocol for achieving the carbonylative cross-coupling of sterically-hindered, ortho-disubstituted aryl ketones is reported. The commercially available PEPPSI-IPr catalyst is shown to efficiently promote the carbonylative cross-coupling of hindered ortho-disubstituted aryl iodides to give diaryl ketones; traditional phosphine catalysts are less effective. Carbonylative Suzuki-Miyaura cross-couplings provide a diverse array of biaryl ketones in good to excellent yields. The same catalyst is also shown to catalyze a carbonylative Negishi cross-coupling reaction, utilizing a variety of alkynyl zinc reagents to give the corresponding alkynyl aryl ketones. Application of this new methodology to the synthesis of the natural product luteolin is reported. PMID:21712966

  3. Lanthanum Tricyanide-Catalyzed Acyl Silane-Ketone Benzoin Additions and Kinetic Resolution of Resultant α-Silyloxyketones

    PubMed Central

    Tarr, James C.

    2010-01-01

    We report the full account of our efforts on the lanthanum tricyanide-catalyzed acyl silane-ketone benzoin reaction. The reaction exhibits a wide scope in both acyl silane (aryl, alkyl) and ketone (aryl-alkyl, alkyl-alkyl, aryl-aryl, alkenyl-alkyl, alkynyl-alkyl) coupling partners. The diastereoselectivity of the reaction has been examined in both cyclic and acyclic systems. Cyclohexanones give products arising from equatorial attack by the acyl silane. The diastereoselectivity of acyl silane addition to acyclic α-hydroxy ketones can be controlled by varying the protecting group to obtain either Felkin-Ahn or chelation control. The resultant α-silyloxyketone products can be resolved with selectivity factors from 10 to 15 by subjecting racemic ketone benzoin products to CBS reduction. PMID:20392127

  4. Modeling the Nanophase Structural Dynamics of Phenylated Sulfonated Poly Ether Ether Ketone Ketone (Ph-SPEEKK) Membranes as a Function of Hydration

    SciTech Connect

    Lins, Roberto D.; Devanathan, Ramaswami; Dupuis, Michel

    2011-03-03

    Solvated phenylated sulfonated poly ether ether ketone ketone (Ph-SPEEKK) membranes in the presence of hydronium ions were modeled by classical molecular dynamics simulations. The characterization of the nanophase structure and dynamics of such membranes was carried out as a function of the water content lambda, where lambda is the number of water molecules per sulfonate group, for lambda values of 3.5, 6, 11, 25, and 40. Analysis of pair correlation functions supports the experimental observation of membrane swelling upon hydration as well the increase in water and hydronium ion diffusion with increasing lambda. While the average number of hydrogen bonds between hydronium ions and sulfonate groups is dramatically affected by the hydration level, the average lifetime of the hydrogen bonds remains essentially constant. The membrane is found to be relatively rigid and its overall flexibility shows little dependence on water content. Compared to Nafion, water and ion diffusion coefficients are considerably smaller at lower hydration levels and room temperature. However, at higher lambda values of 25 and 40 these coefficients are comparable to those in Nafion at a lambda value of 16. This study also shows that water diffusion in Ph-SPEEKK membranes at low hydration levels can be significantly improved by raising the temperature with important implications for proton conductivity.

  5. Molecular modeling of the morphology and transport properties of two direct methanol fuel cell membranes: phenylated sulfonated poly(ether ether ketone ketone) versus Nafion

    SciTech Connect

    Devanathan, Ramaswami; Idupulapati, Nagesh B.; Dupuis, Michel

    2012-08-14

    We have used molecular dynamics simulations to examine membrane morphology and the transport of water, methanol and hydronium in phenylated sulfonated poly ether ether ketone ketone (Ph-SPEEKK) and Nafion membranes at 360 K for a range of hydration levels. At comparable hydration levels, the pore diameter is smaller, the sulfonate groups are more closely packed, the hydronium ions are more strongly bound to sulfonate groups, and the diffusion of water and hydronium is slower in Ph-SPEEKK relative to the corresponding properties in Nafion. The aromatic carbon backbone of Ph-SPEEKK is less hydrophobic than the fluorocarbon backbone of Nafion. Water network percolation occurs at a hydration level ({lambda}) of {approx}8 H{sub 2}O/SO{sub 3}{sup -}. At {lambda} = 20, water, methanol and hydronium diffusion coefficients were 1.4 x 10{sup -5}, 0.6 x 10{sup -5} and 0.2 x 10{sup -5} cm{sup 2}/s, respectively. The pore network in Ph-SPEEKK evolves dynamically and develops wide pores for {lambda} > 20, which leads to a jump in methanol crossover and ion transport. This study demonstrates the potential of aromatic membranes as low-cost challengers to Nafion for direct methanol fuel cell applications and the need to develop innovative strategies to combat methanol crossover at high hydration levels.

  6. Polyether ether ketone encased monolith frits made of polyether ether ketone tubing with a 0.25 mm opening resulting in an improved separation performance in liquid chromatography.

    PubMed

    Park, Sin Young; Cheong, Won Jo

    2016-05-01

    Tiny polyether ether ketone encased monolith frits have been prepared by modified catalytic sulfonation of the inner surface of polyether ether tubing (1.6 mm od, 0.25 mm id) followed by modified formation of organic monolith and cutting of the tubing into slices. The frit was placed below the central hole of the column outlet union and supported by a combination of a silica capillary (0.365 mm od, 0.05 mm id) and a polyether ether ketone sleeve (1.6 mm od, 0.38 mm id) tightened with a nut and a ferrule when the column was packed to prevent sinking of the frit element into the union hole (0.25 mm opening) otherwise. The column packed this way with the frits investigated in this study has shown better separation performance owing to the reduced frit volume in comparison to the column packed with a commercial stainless-steel screen frit. This study establishes the strategy of disposable microcolumns in which cheap disposable frits are used whenever the column is re-packed to yield columns of even better chromatographic performance than the columns with commercial frits. PMID:26910135

  7. Synthesis and characterizations of electrospun sulfonated poly (ether ether ketone) SPEEK nanofiber membrane

    NASA Astrophysics Data System (ADS)

    Hasbullah, N.; Sekak, K. A.; Ibrahim, I.

    2016-07-01

    A novel electrospun polymer electrolyte membrane (PEM) based on Sulfonated Poly (ether ether ketone) were prepared and characterized. The poly (ether ether ketone) PEEK was sulfonated using concentrated sulfuric acid at room temperature for 60 hours reaction time. The degree sulfonation (DS) of the SPEEK are 58% was determined by H1 NMR using area under the peak of the hydrogen shielding at aromatic ring of the SPEEK. Then, the functional group of the SPEEK was determined using Fourier transfer infrared (FTIR) showed O-H vibration at 3433 cm-1 of the sulfonated group (SO2-OH). The effect of the solvent and polymer concentration toward the electrospinning process was investigated which, the DMAc has electrospun ability compared to the DMSO. While, at 20 wt.% of the polymer concentration able to form a fine and uniform nanofiber, this was confirmed by FESEM that shown electrospun fiber mat SPEEK surface at nano scale diameter.

  8. The CIDNP-detected laser-flash photolysis of benzyl ketones

    NASA Astrophysics Data System (ADS)

    Läufer, Martina; Dreeskamp, Herbert

    The near UV photolysis of benzyl ketones leads to acyl and benzyl radicals via Norrish type I cleavage. A minor reaction pathway for these radicals is the formation of semibenzenes. Several not previously recognized polarizations of semibenzene products in the CIDNP spectra of methyl benzyl, isopropyl benzyl, benzyl phenyl, and dibenzyl ketone were found using a 308 nm pulsed excimer laser and a 250 MHz 1H NMR spectrometer. The chemical shifts of the semibenzenes formed as recombination products are given and the spectrum of benzyl semibenzene, stable under the experimental conditions, is analyzed. The evolution of main and minor diamagnetic products on a microsecond time scale is presented. From these data the rate of the diffusion-controlled termination reaction of benzyl radicals to bibenzyl was found to be 7 × 10 9M-1 s -1 in benzene solution at room temperature.

  9. Nickel-catalyzed transfer hydrogenation of ketones using ethanol as a solvent and a hydrogen donor.

    PubMed

    Castellanos-Blanco, Nahury; Arévalo, Alma; García, Juventino J

    2016-09-14

    We report a nickel(0)-catalyzed direct transfer hydrogenation (TH) of a variety of alkyl-aryl, diaryl, and aliphatic ketones with ethanol. This protocol implies a reaction in which a primary alcohol serves as a hydrogen atom source and solvent in a one-pot reaction without any added base. The catalytic activity of the nickel complex [(dcype)Ni(COD)] (e) (dcype: 1,2-bis(dicyclohexyl-phosphine)ethane, COD: 1,5-cyclooctadiene), towards transfer hydrogenation (TH) of carbonyl compounds using ethanol as the hydrogen donor was assessed using a broad scope of ketones, giving excellent results (up to 99% yield) compared to other homogeneous phosphine-nickel catalysts. Control experiments and a mercury poisoning experiment support a homogeneous catalytic system; the yield of the secondary alcohols formed in the TH reaction was monitored by gas chromatography (GC) and NMR spectroscopy. PMID:27511528

  10. Synthesis of 1,4-enamino ketones by [3,3]-rearrangements of dialkenylhydroxylamines.

    PubMed

    Pecak, Wiktoria H; Son, Jongwoo; Burnstine, Amy J; Anderson, Laura L

    2014-07-01

    The synthesis of 1,4-enamino ketones has been achieved through the [3,3]-rearrangement of dialkenylhydroxylamines generated from the addition of N-alkenylnitrones to electron-deficient allenes. The mild conditions required for this reaction, and the simultaneous installation of a fluorenyl imine N-protecting group as a consequence of the rearrangement, avoid spontaneous cyclization of the 1,4-enamino ketones to form the corresponding pyrroles and allow for the isolation and controlled divergent functionalization of these reactive intermediates. The optimization, scope, and tolerance of the new method are discussed with demonstrations of the utility of the products for the synthesis of pyrroles, 1,4-diones, and furans. PMID:24961680