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Sample records for beta di ketonate

  1. Organocatalytic enantioselective indole alkylations of alpha,beta-unsaturated ketones.

    PubMed

    Chen, Wei; Du, Wei; Yue, Lei; Li, Rui; Wu, Yong; Ding, Li-Sheng; Chen, Ying-Chun

    2007-03-07

    The C3-selective enantioselective Michael-type Friedel-Crafts alkylations of indoles with nonchelating alpha,beta-unsaturated alkyl ketones, catalysed by a chiral primary amine derived from natural cinchonine, were investigated. The reactions, in the presence of 30 mol% catalyst, were smoothly conducted at 0 to -20 degrees C. Moderate to good ee (47-89%) has been achieved.

  2. Thionation of some alpha,beta-unsaturated steroidal ketones.

    PubMed

    Krstić, Natalija M; Bjelaković, Mira S; Dabović, Milan M; Pavlović, Vladimir D

    2010-05-12

    The reactions of selected alpha,beta-unsaturated steroidal ketones with Lawesson's reagent (LR) in CH(2)Cl(2) and toluene under the standard reaction conditions and with a combination of phosphorus pentasulfide with hexamethyldisiloxane (P(4)S(10)/HMDO) in 1,2-dichlorobenzene (ODCB) under microwave irradiation were investigated and for this purpose several cholestane, androstane and pregnane carbonyl derivatives were chosen. Depending on the reagent and the solvent, 19 new sulfur containing compounds, including dithiones 4c and 4d, alpha,beta-unsaturated 3-thiones 3a-e, dimer-sulfides 2a-e, 1,2,4-trithiolanes 5a-e and phosphonotrithioates 6b-e were synthesized. All newly prepared compounds were characterized by IR, (1)H- and (13)C-NMR spectroscopy and elemental analysis.

  3. Organocatalytic C3-selective Friedel-Crafts alkylations of indoles with alpha,beta-unsaturated ketones.

    PubMed

    Li, Dong-Ping; Guo, Ying-Cen; Ding, Yu; Xiao, Wen-Jing

    2006-02-21

    The use of an equimolar amount of pyrrolidine and HClO4 (30 mol%) was found to be effective in promoting the conjugate addition of indoles to (E)-alpha,beta-unsaturated ketones, affording the corresponding beta-indolyl ketones in excellent yields.

  4. Chiral N-phosphonyl imine chemistry: asymmetric synthesis of alpha-alkyl beta-amino ketones by reacting phosphonyl imines with ketone-derived enolates.

    PubMed

    Ai, Teng; Han, Jianlin; Chen, Zhong-Xiu; Li, Guigen

    2009-02-01

    A series of new chiral syn-alpha-branched beta-amino ketones has been synthesized by reacting chiral phosphonyl imines with ketone-derived enolates. The N-protection group on imine auxiliary was found to be crucial to the asymmetric induction. The absolute stereochemistry has been unambiguously determined by converting a product to a known sample.

  5. beta-Hydroxysulfoxides as chiral cyclic ketone equivalents: enantioselective synthesis of polysubstituted cyclohexanones, cyclohexenones and cyclohexenediones.

    PubMed

    Carreño, M Carmen; Pérez-González, Manuel; Ribagorda, María; Somoza, Alvaro; Urbano, Antonio

    2002-12-21

    The beta-hydroxysulfoxide moiety, after oxidation to sulfone, acts as a masked carbonyl group in a cyclic system, opening an easy access to differently substituted enantiomerically pure cyclic ketones by means of aluminium-mediated conjugate additions, stereoselective reductions and elimination by retrocondensation in basic medium.

  6. Directed reductive amination of beta-hydroxy-ketones: convergent assembly of the ritonavir/lopinavir core.

    PubMed

    Menche, Dirk; Arikan, Fatih; Li, Jun; Rudolph, Sven

    2007-01-18

    An efficient procedure for the directed reductive amination of beta-hydroxy-ketones (3) for the stereoselective preparation of 1,3-syn-amino alcohols (6) is reported. The operationally simple protocol uses Ti(iOPr)4 for coordination of the intermediate imino alcohol (5) and PMHS as the reducing agent. The method was expanded to an asymmetric aldol reductive amination sequence to allow a highly convergent synthesis of the hydroxy-amine core of the HIV-protease inhibitors ritonavir and lopinavir. [reaction: see text].

  7. Selective synthesis of alpha,beta-unsaturated ketones by dibutyltin dimethoxide-catalyzed condensation of aldehydes with alkenyl trichloroacetates.

    PubMed

    Yanagisawa, Akira; Goudu, Riku; Arai, Takayoshi

    2004-11-11

    Various alpha,beta-unsaturated ketones were stereoselectively synthesized in high yields up to 94% by a condensation reaction between alkenyl trichloroacetates and aldehydes using dibutyltin dimethoxide as a catalyst in the presence of methanol. This process is superior to the classical Claisen-Schmidt condensation with respect to mildness of the base catalyst and product selectivity.

  8. Asymmetric synthesis of substituted homotropinones from N-sulfinyl beta-amino ketone ketals. (-)-Euphococcinine and (-)-adaline.

    PubMed

    Davis, Franklin A; Edupuganti, Ram

    2010-02-19

    Sulfinimine-derived N-sulfinyl beta-amino ketone ketals on heating with NH(4)OAc:HOAc undergo a four-step intramolecular Mannich cyclization cascade reaction to give homotropinones, such as (-)-euphococcinine, in excellent yields as single isomers.

  9. Structural, electrochemical and optical properties of di-2-pyridyl ketone 2-furoic acid hydrazone (dpkfah)

    NASA Astrophysics Data System (ADS)

    Bakir, Mohammed; Gyles, Colin

    2003-04-01

    Crystals of di-2-pyridyl ketone 2-furoic acid hydrazone (dpkfah), obtained from a dmso (dimethylsulfoxide) solution of dpkfah, are in the monoclinic space group, P2 1/ n. Structural analysis reveals planar hydrazone moiety, non-coplanar pyridine rings and infinite chains of anti-parallel dpkfah dimers interlocked via a web of hydrogen bonds. Electrochemical measurements on dpkfah in non-aqueous solvents show solvent dependence, single and multi-electronic transfers and electrochemical transformation(s) following the first oxidative or reductive electronic transfer. Optical measurements on dpkfah in non-aqueous solvents show strong solvent dependence. In non-polar solvent such as CH 2Cl 2 a single electronic absorption band with extinction coefficient of 18,600±2000 M -1 cm -1 appeared at 325 nm and in polar solvents a low-energy absorption band at ˜396 nm and a high-energy absorption band at ˜320-335 nm appeared that are concentration, temperature and salt dependent. In the presence and absence of NaBF 4 and NaBH 4, extinction coefficients of 21,000±2000 and 22,500 M -1 cm -1, and 17,200±2,000 and 23,000 M -1 cm -1 were calculated for the low and high energy electronic states of dpkfah in dmf and dmso, respectively at 295 K. Thermo-optical measurements on dpkfah in dmso and dmf confirmed the reversible interconversion between the high and low energy electronic states of dpkfah and allowed calculations of their thermodynamic activation parameters and gave changes in enthalpy (Δ H∅) of +47.5±1.2 and -16.3±0.4 kJ mol -1, entropy (Δ S∅) of +147.7±3.8 and -64.4±1.64 J mol -1 K -1 and free energy (Δ G∅) of +3.49±0.2 and +2.85±0.2 kJ mol -1 and hence equilibrium constant ( K) of +0.25±0.05 and +0.32±0.05 in dmso and dmf, respectively. The reversible BH 4-/BF 4- interconversion of the electronic states of dpkfah points to weak non-covalent interactions between these species and dpkfah and possible use of dpkfah as a spectrophotometric sensor for a

  10. Visible light-mediated oxidative quenching reaction to electron-rich epoxides: highly regioselective synthesis of α-bromo (di)ketones and mechanism study.

    PubMed

    Guo, Lin; Yang, Chao; Zheng, Lewei; Xia, Wujiong

    2013-09-21

    A novel and simple procedure was developed for the regioselective synthesis of α-bromo (di)ketones from electron-rich epoxides via visible light photoredox catalysis. Through optimization of solvent and light source, the reaction can be rapidly achieved under mild conditions. Moreover, the possible reaction mechanism was proposed and further supported by control experiments.

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

    PubMed

    Curti, Christophe; Gellis, Armand; Vanelle, Patrice

    2007-04-18

    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.

  12. Nuclear magnetic resonance and optosensing properties of di-2-thienyl ketone p-nitrophenylhydrazone (DSKNPH) in non-aqueous media.

    PubMed

    Bakir, Mohammed; Green, Orville; Gyles, Colin; Mangaro, Basil; Porter, Roy

    2004-03-10

    The compound di-2-thienyl ketone p-nitrophenylhydrazone (DSKNPH) melting point 168-170 degrees C was isolated in good yield from the reaction between di-2-thienyl ketone (DSK) and p-nitrophenylhydrazine in refluxing ethanol containing a few drop of concentrated HCl. Nuclear magnetic resonance studies on DSKNPH in non-aqueous solvents revealed strong solvent and temperature dependence due to solvent-solute interactions. Optical measurements on DSKNPH in DMSO in the presence and absence of KPF(6) gave extinction coefficients of 83,300+/-2000 and 25,600+/-2000M(-1)cm(-1) at 612 and 427nm at 295K. In CH(2)Cl(2), extinction coefficient of 34,000+/-2000M(-1)cm(-1) was calculated at 422nm. When DMSO solutions of DSKNPH were allowed to interact with DMSO solutions of NaBH(4) the low energy electronic state becomes favorable and when DMSO solutions of DSPKNPH where allowed to interact with DMSO solutions of KPF(6) or NaBF(4), the high energy electronic state becomes favorable. The reversible BH(4)(-)/BF(4)(-) interconversion points to physical interactions between these species and DSKNPH and hints to the possible use of DSKNPH as a spectrophotometric sensor for a variety of physical and chemical stimuli. Thermo-optical measurements on DSKNPH in DMSO confirmed the reversible interconversion between the high and low energy electronic states of DSKNPH and allowed for the calculations of the thermodynamic activation parameters of DSKNPH. Changes in enthalpy (DeltaH(slashed circle)) of +57.67+/-4.20; 27.15+/-0.90kJmol(-1), entropy (DeltaS(slashed circle)) of +160+/-12.88; 83+/-2.91Jmol(-1) and free energy (DeltaG(slashed circle)) of -8.52+/-0.40; 2.66+/-0.25kJmol(-1) were calculated at 295K in the absence and presence of NaBH(4), respectively. Manipulation of the equilibrium distribution of the high and low energy electronic states of DSKNPH allowed for the use of these systems (DSKNPH and surrounding solvent molecules) as molecular sensors for group I and II metal ions. Group

  13. Interactions of alpha, beta-unsaturated aldehydes and ketones with human glutathione S-transferase P1-1.

    PubMed

    van Iersel, M L; Ploemen, J P; Lo Bello, M; Federici, G; van Bladeren, P J

    1997-12-12

    In the present study the irreversible inhibition of human glutathione S-transferase P1-1 (GSTP1-1) by alpha, beta-unsaturated aldehydes and ketones was studied. When GSTP1-1 was incubated with a 50-fold molar excess of the aldehydes acrolein (ACR) and 4-hydroxy-2-nonenal (HNE) and the ketones curcumin (CUR) and ethacrynic acid (EA) at 22 degrees C, all of them inactivated GSTP1-1. The remaining activity after 4 h of incubation in all cases was lower than 10%. The aldehydes crotonaldehyde (CRA), cinnamaldehyde (CA) and trans-2-hexenal were found to inhibit GSTP1-1 only at a 5000-fold molar excess and even then, for example, for CA a higher remaining activity of 17% was observed. The same inhibition experiments were conducted with 3 mutants of GSTP1-1: the C47S and C101S mutants and the double mutant C47S/C101S. Remaining activity for C47S varied between +/- 40% for CRA, CA, CUR and HEX and +/- 80% for ACR, EA and HNE. For C101S it varied between 0 and 9% and for the double mutant C47S/C101S, activity after 4 h of incubation was variable. Again it varied between +/- 40% for CRA, CA, CUR and HEX and +/- 80% for ACR, EA and HNE. EA is known to react almost exclusively with cysteine 47. When [14C]EA was incubated with the GSTP1-1, modified by the alpha, beta-unsaturated carbonyl compounds, no [14C]EA was incorporated in the enzyme, indicating that in all cases this cysteine residue was one of the major targets. Since Michael addition with these reagents is known to be reversible, the results of incubation of the inactivated enzymes with an excess of glutathione (GSH) were determined. For all compounds, a restoration of the catalytic activity was observed. The results indicate that alpha, beta-unsaturated carbonyl derivatives inhibit GSTP1-1 irreversibly mainly by binding to cysteine residues of GSTP1-1, especially Cys-47, This means that some of these compounds (e.g. CUR) might modify GST activity in vivo when GSH concentrations are low by covalent binding to the enzyme.

  14. Chemistry of oxalyl derivatives of methyl ketones. XLVI. Reaction of. beta. -bromoaroylpyruvic esters with urea

    SciTech Connect

    Andreichikov, Yu.S.; Plakhina, G.D.

    1987-09-20

    The substitution of the bromine atom in methyl ..beta..-bromoaroylpyruvates by urea is accompanied by cyclization of the substitution product. Depending on the reaction conditions, this leads either to 6-aroyl-5-hydroxyuracils or to 5-aryl-4-methoxycarbonyl-2,3-dihydro-2-imidazolones. The UV spectra were recorded on a Specord UV-Vis spectrometer in ethanol with the substances at concentrations of 10/sup -4/-10/sup -5/ M. The IR spectra were recorded in Vaseline oil on a UR-20 spectrometer. The PMR spectra were recorded in deuteroacetone on an RS-60 spectrometer with HMDS as internal standard. The mass spectra were recorded on a Varian Mat-311 spectrometer at 70 eV.

  15. Raspberry Ketone

    MedlinePlus

    ... and breast-feeding: There is not enough reliable information about the safety of taking raspberry ketone if you are pregnant or breast feeding. Stay on the safe side and avoid use. Diabetes: Raspberry ketone might lower blood sugar levels. In theory, raspberry ketone might make blood sugar drop too ...

  16. Anionic four-electron donor-based palladacycles as catalysts for addition reactions of arylboronic acids with alpha,beta-unsaturated ketones, aldehydes, and alpha-ketoesters.

    PubMed

    He, Ping; Lu, Yong; Dong, Cheng-Guo; Hu, Qiao-Sheng

    2007-01-18

    Anionic four-electron donor-based palladacycle-catalyzed 1,4-additions of arylboronic acids with alpha,beta-unsaturated ketones and 1,2-additions of arylboronic acids with aldehydes and alpha-ketoesters are described. Our study demonstrated that palladacycles were highly efficient, practical catalysts for these addition reactions. The work described here not only opened a new paradigm for the application of palladacycles, but may also pave the road for other metalacycles as practically useful catalysts for such addition reactions including asymmetric ones. [reaction: see text].

  17. Hydride-mediated homogeneous catalysis. Catalytic reduction of. alpha. ,. beta. -unsaturated ketones using ((Ph sub 3 P)CuH) sub 6 and H sub 2

    SciTech Connect

    Mahoney, W.S.; Stryker, J.M. )

    1989-11-22

    Hydride-mediated reduction of {alpha},{beta}-unsaturated ketones catalytic in the hydride reagent is reported using ((Ph{sub 3}P)CuH){sub 6} and molecular hydrogen. The reaction proceeds at room temperature and is highly regioselective, affording either the product of conjugate reduction or complete 1,4- and 1,2-reduction to the saturated alcohol, depending on reaction conditions. In the presence of excess phosphine, the process is homogeneous and chemoselective: isolated double bonds are not hydrogenated, even under forcing conditions. This novel catalytic reduction appears to proceed via the heterolytic activation of molecular hydrogen by highly reactive copper(I) enolate and alkoxide intermediates.

  18. In vitro and in vivo antimycobacterial activities of ketone and amide derivatives of quinoxaline 1,4-di-N-oxide

    PubMed Central

    Villar, Raquel; Vicente, Esther; Solano, Beatriz; Pérez-Silanes, Silvia; Aldana, Ignacio; Maddry, Joseph A.; Lenaerts, Anne J.; Franzblau, Scott G.; Cho, Sang-Hyun; Monge, Antonio; Goldman, Robert C.

    2008-01-01

    Objectives To evaluate a novel series of quinoxaline 1,4-di-N-oxides for in vitro activity against Mycobacterium tuberculosis and for efficacy in a mouse model of tuberculosis (TB). Methods Ketone and amide derivatives of quinoxaline 1,4-di-N-oxide were evaluated in in vitro and in vivo tests including: (i) activity against M. tuberculosis resistant to currently used antitubercular drugs including multidrug-resistant strains (MDR-TB resistant to isoniazid and rifampicin); (ii) activity against non-replicating persistent (NRP) bacteria; (iii) MBC; (iv) maximum tolerated dose, oral bioavailability and in vivo efficacy in mice; and (v) potential for cross-resistance with another bioreduced drug, PA-824. Results Ten compounds were tested on single drug-resistant M. tuberculosis. In general, all compounds were active with ratios of MICs against resistant and non-resistant strains of ≤4.00. One compound, 5, was orally active in a murine model of TB, bactericidal, active against NRP bacteria and active on MDR-TB and poly drug-resistant clinical isolates (resistant to 3–5 antitubercular drugs). Conclusions Quinoxaline 1,4-di-N-oxides represent a new class of orally active antitubercular drugs. They are likely bioreduced to an active metabolite, but the pathway of bacterial activation was different from PA-824, a bioreducible nitroimidazole in clinical trials. Compound 5 was bactericidal and active on NRP organisms indicating that activation occurred in both growing and non-replicating bacteria leading to cell death. The presence of NRP bacteria is believed to be a major factor responsible for the prolonged nature of antitubercular therapy. If the bactericidal activity and activity on non-replicating bacteria in vitro translate to in vivo conditions, quinoxaline 1,4-di-N-oxides may offer a path to shortened therapy. PMID:18502817

  19. Acetate/di-2-pyridyl ketone oximate "blend" as a source of high-nuclearity nickel(II) clusters: dependence of the nuclearity on the nature of the inorganic anion present.

    PubMed

    Stamatatos, Theocharis C; Diamantopoulou, Eleanna; Raptopoulou, Catherine P; Psycharis, Vassilis; Escuer, Albert; Perlepes, Spyros P

    2007-04-02

    The use of di-2-pyridyl ketone oxime [(py)2CNOH] in reactions with Ni(O2CMe)2.4H2O, in the presence or absence of extra inorganic anions (N3- and SCN-) has led to Ni4, Ni5, and Ni7 clusters; the magnetic study of the heptanuclear nickel(II) complex reveals an S = 3 ground state.

  20. 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 ...

  1. Sulfur Ylides. Communication 1. Cyclopropanation of. cap alpha. ,. beta. -unsaturated Ketones with Ethyl (dimethylsulfuranylidene) acetate generated in the presence of phase-transfer catalysts

    SciTech Connect

    Tolstikov, G.A.; Galin, F.Z.; Iskandarova V.N.; Khalilov, L.M.; Panasenko, A.A.

    1986-04-01

    This paper presents a modified method for the cyclopropanation of alpha, beta-unsaturated ketones with ethyl (dimethylsulfuranylidene) acetate, generated in situ from a sulfonium salt with 85% KOH in the presence of a phase-transfer catalyst, and studies the sterochemistry of the polysubstituted cyclopropanes. The chemical shifts of the carbon atoms of the cyclopropane rings of the isomer pairs are close together in the C 13 NMR spectra, which makes the assignment of the signals of C/sup 2/ and C/sup 3/ and the sterochemical assignment of each isomer to the cis and the trans series difficult. It is shown that the signals of the carboxyl carbon atoms differ not more than 0.65 ppm in the isomer pairs.

  2. Bacterial production of methyl ketones

    DOEpatents

    Beller, Harry R.; Goh, Ee-Been

    2017-01-31

    The present invention relates to methods and compositions for increasing production of methyl ketones in a genetically modified host cell that overproduces .beta.-ketoacyl-CoAs through a re-engineered .beta.-oxidation pathway and overexpresses FadM.

  3. Mechanism of the addition of nonenolizable aldehydes and ketones to (Di)metallenes (R(2)X=YR(2), X = Si, Ge Y = C, Si, Ge): a density functional and multiconfigurational perturbation theory study.

    PubMed

    Mosey, Nicholas J; Baines, Kim M; Woo, Tom K

    2002-11-06

    The mechanism of the addition of nonenolizable aldehydes and ketones to group 14 (di)metallenes has been examined through a theoretical study of the addition of formaldehyde to Si=C, Ge=C, Si=Si, Si=Ge, and Ge=Ge bonds at the B3LYP/6-311++G(d,p) and CAS-MCQDPT2/6-31++G(d,p) levels of theory. The reaction pathways located can be grouped as either involving the formation of singlet diradical or zwitterionic intermediates or as concerted processes. Within each group of reaction pathways, several different mechanisms have been located, with not all mechanisms being available to all of the (di)metallenes. It was found that for reactions in which a Si-O bond results (i.e., addition to Si=C, Si=Si, and Si=Ge) both diradical and zwitterionic intermediates are possible; however, the formation of diradical intermediates was not found for reactions that result in the formation of a Ge-O bond (addition to Ge=C and Ge=Ge). The underlying cause of this pathway selectivity is examined, as well as the effect of solvent on the relative energies of the pathways. The results of the study shed light on the cause of experimentally obtained results regarding the mechanism of the reaction of (di)metallenes with nonenolizable ketones and aldehydes.

  4. 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

  5. Synthesis, and molecular sensing behavior of fac-[Re(CO)3(κ2-N,N-dpksc)Cl], dpksc = di-2-pyridyl ketone semicarbazone

    NASA Astrophysics Data System (ADS)

    Bakir, Mohammed; Brown, Ordel

    2013-01-01

    When [Re(CO)5Cl] was allowed to react with di-2-pyridyl ketone semicarbazone hydrochloride (dpksc.HCl) in refluxing toluene, fac-[Re(CO)3(κ2-N,N-dpksc)Cl] was isolated. The identity of fac-[Re(CO)3(κ2-N,N-dpksc)Cl] was elucidated from the results of its elemental analysis and confirmed using a number of spectroscopic measurements. Spectroscopic measurements done on non-aqueous solvents divulged sensitivity of fac-[Re(CO)3(κ2-N,N-dpksc)Cl] to changes in its surroundings. 1H NMR studies revealed significant solvent dependence as manifested by the chemical shift variations; the exchange of the amine protons with solvent deuterium in CDCl3 and d6-acetone; the temperature dependence of the chemical shifts of the amine and amide protons and insignificant temperature dependence of the aromatic proton. The electronic absorption spectra of fac-[Re(CO)3(κ2-N,N-dpksc)Cl] measured on non-aqueous solvents disclosed two high energy intra-ligand charge transfer (ILCT) transitions. Optical measurements performed on protophilic solutions of fac-[Re(CO)3(κ2-N,N-dpksc)Cl] in the presence of bases and acids showed the appearance and disappearance of a low energy ILCT electronic transitions and established reversible inter-conversion between fac-[Re(CO)3(κ2-N,N-dpksc)Cl] and its conjugate base, fac-[Re(CO)3(κ2-N,N-dpksc-H)Cl]-. Thermo-optical measurements done on protophilic solutions of fac-[Re(CO)3(κ2-N,N-dpksc)Cl] disclosed the absence of thermal acid-base inter-conversion between fac-[Re(CO)3(κ2-N,N-dpksc)Cl] and fac-[Re(CO)3(κ2-N,N-dpksc-H)Cl]- and established reversible electronic transfer between the high energy electronic transitions of fac-[Re(CO)3(κ2-N,N-dpksc)Cl]. Optosensing measurements done on protophilic solutions of fac-[Re(CO)3(κ2-N,N-dpksc)Cl] showed acids and bases in concentrations as low as 1.00 × 10-10 M can be detected and determined using protophilic solutions of of fac-[Re(CO)3(κ2-N,N-dpksc)Cl]. Electrochemical measurements on dmf solutions of fac

  6. 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 ...

  7. Solvent-controlled diastereoselective synthesis of cyclopentane derivatives by a [3 + 2] cyclization reaction of alpha,beta-disubstituted (alkenyl)(methoxy)carbene complexes with methyl ketone lithium enolates.

    PubMed

    Barluenga, José; Alonso, Jorge; Fañanás, Francisco J

    2003-03-05

    Reaction of alpha,beta-unsaturated methoxycarbene complexes 1 and 11 with methyl ketone lithium enolates 2 leads to the corresponding five-membered carbocyclic compounds 4 or diast-4 and 12. The influence of the solvent and/or cosolvent (PMDTA), which turned out to be crucial to direct the reaction to 4 or diast-4, is studied, and a tentative mechanism according to these facts is proposed. In addition, the reaction of carbene complex 1a with alkynyl methyl ketone lithium enolates can be directed to the formal [3 + 2] or [4 + 1] cyclization products by a slight variation of the reaction conditions. Finally, consecutive three-component coupling reactions with carbene complex 1a, lithium enolates 2, and aldehydes 18 to give, in a diastereoselective way, hydroxy carbonyl compounds 19 and tricyclic polyethers 20 are presented.

  8. Aromatic ketones with terminal vinyl groups

    SciTech Connect

    Uvarova, L.R.; Burykina, L.K.; Zubareva, M.M.; Polyanskii, I.D.

    1988-12-20

    The Friedel-Crafts acylation of a hydrocarbon by an acylating agent containing bromoalkyl substituents gave a series of new ketones. Their subsequent dehydrobromination with potassium tert-butoxide gave high yields of aromatic ketones containing terminal vinyl groups. The reaction was conducted both with /beta/-bromoethylbenzene and with 4-(/beta/-bromoethyl)-benzoyl chloride and also with both compounds simultaneously. The structures of the synthesized compounds were confirmed by the PMR, IR, UV, and mass spectra and also by the data from elemental analysis.

  9. Beta-catenin deficiency causes DiGeorge syndrome-like phenotypes through regulation of Tbx1.

    PubMed

    Huh, Sung-Ho; Ornitz, David M

    2010-04-01

    DiGeorge syndrome (DGS) is a common genetic disease characterized by pharyngeal apparatus malformations and defects in cardiovascular, craniofacial and glandular development. TBX1 is the most likely candidate disease-causing gene and is located within a 22q11.2 chromosomal deletion that is associated with most cases of DGS. Here, we show that canonical Wnt-beta-catenin signaling negatively regulates Tbx1 expression and that mesenchymal inactivation of beta-catenin (Ctnnb1) in mice caused abnormalities within the DGS phenotypic spectrum, including great vessel malformations, hypoplastic pulmonary and aortic arch arteries, cardiac malformations, micrognathia, thymus hypoplasia and mislocalization of the parathyroid gland. In a heterozygous Fgf8 or Tbx1 genetic background, ectopic activation of Wnt-beta-catenin signaling caused an increased incidence and severity of DGS-like phenotypes. Additionally, reducing the gene dosage of Fgf8 rescued pharyngeal arch artery defects caused by loss of Ctnnb1. These findings identify Wnt-beta-catenin signaling as a crucial upstream regulator of a Tbx1-Fgf8 signaling pathway and suggest that factors that affect Wnt-beta-catenin signaling could modify the incidence and severity of DGS.

  10. Metal-organic frameworks with 1,4-di(1H-imidazol-4-yl)benzene and varied carboxylate ligands for selectively sensing Fe(iii) ions and ketone molecules.

    PubMed

    Liu, Zhi-Qiang; Zhao, Yue; Zhang, Xiu-Du; Kang, Yan-Shang; Lu, Qing-Yi; Azam, Mohammad; Al-Resayes, Saud I; Sun, Wei-Yin

    2017-10-03

    Four new metal-organic frameworks (MOFs) [Zn(L)(bpdc)]·1.6H2O (1), [Co(L)(bpdc)]·H2O (2), [Ni3(L)2(bptc)2(H2O)10]·2H2O (3) and [Cd2(L)(Hbptc)2] (4) were achieved by reactions of the corresponding metal salt with mixed organic ligands of 1,4-di(1H-imidazol-4-yl)benzene (L) and 4,4'-benzophenonedicarboxylic acid (H2bpdc) or biphenyl-2,4',5-tricarboxylic acid (H3bptc). They exhibit varied structures: MOFs 1 and 4 are porous three-dimensional (3D) frameworks, while 2 is an infinite one-dimensional (1D) chain and 3 is a two-dimensional (2D) network. Remarkably, 1 and 4 can act as potential fluorescent materials for sensing Fe(iii) ions and different ketone molecules with high selectivity and sensitivity. In addition, MOF 1 shows selective adsorption of CO2 over N2.

  11. Ketones suppress brain glucose consumption.

    PubMed

    LaManna, Joseph C; Salem, Nicolas; Puchowicz, Michelle; Erokwu, Bernadette; Koppaka, Smruta; Flask, Chris; Lee, Zhenghong

    2009-01-01

    The brain is dependent on glucose as a primary energy substrate, but is capable of utilizing ketones such as beta-hydroxybutyrate (beta HB) and acetoacetate (AcAc), as occurs with fasting, prolonged starvation or chronic feeding of a high fat/low carbohydrate diet (ketogenic diet). In this study, the local cerebral metabolic rate of glucose consumption (CMRglu; microM/min/100g) was calculated in the cortex and cerebellum of control and ketotic rats using Patlak analysis. Rats were imaged on a rodent PET scanner and MRI was performed on a 7-Tesla Bruker scanner for registration with the PET images. Plasma glucose and beta HB concentrations were measured and 90-minute dynamic PET scans were started simultaneously with bolus injection of 2-Deoxy-2[18F]Fluoro-D-Glucose (FDG). The blood radioactivity concentration was automatically sampled from the tail vein for 3 min following injection and manual periodic blood samples were taken. The calculated local CMRGlu decreased with increasing plasma BHB concentration in the cerebellum (CMRGlu = -4.07*[BHB] + 61.4, r2 = 0.3) and in the frontal cortex (CMRGlu = -3.93*[BHB] + 42.7, r2 = 0.5). These data indicate that, under conditions of ketosis, glucose consumption is decreased in the cortex and cerebellum by about 10% per each mM of plasma ketone bodies.

  12. [Preparation and evaluation of 2,6-di-O-pentyl-beta-cyclodextrin bonded silica stationary phase for high performance liquid chromatography].

    PubMed

    Liu, Liwen; Luo, Aiqin; Dai, Rongji; Ge, Xiaoxia; Yang, Shaoning

    2004-11-01

    In order to improve the chiral separation capability of the conventional beta-cyclodextrin bonded-silica gel stationary phase, 2,6-di-O-pentyl-beta-cyclodextrin bonded stationary phase (PCDS) was prepared via a long spacer. The resulted bonded-silica stationary phase was characterized by three methods, namely Fourier transform infrared, Molisch color reaction, X-ray optical electrical energy spectrogram. The chromatographic performances of PCDS were investigated by using liquid chromatography with toluene, dimethyl phthalate, and phenanthrene as solutes, and their retention mechanism was investigated and discussed. The results show that the introduction of pentyl to beta-cyclodextrin leads to enhancement of the retention of the solutes. The chiral separation capability of the new bonded-silica stationary phase was evaluated by using liquid chromatography with some chiral drugs. Some of the enantiomers such as chlorphenamine maleate and bupropion hydrochloride were separated by heptakis (2,6-di-O-pentyl)-beta-cyclodextrin bonded silica stationary.

  13. Optimization of novel di-substituted cyclohexylbenzamide derivatives as potent 11 beta-HSD1 inhibitors.

    PubMed

    McMinn, Dustin L; Rew, Yosup; Sudom, Athena; Caille, Seb; Degraffenreid, Michael; He, Xiao; Hungate, Randall; Jiang, Ben; Jaen, Juan; Julian, Lisa D; Kaizerman, Jacob; Novak, Perry; Sun, Daqing; Tu, Hua; Ursu, Stefania; Walker, Nigel P C; Yan, Xuelei; Ye, Qiuping; Wang, Zhulun; Powers, Jay P

    2009-03-01

    Novel 4,4-disubstituted cyclohexylbenzamide inhibitors of 11beta-HSD1 were optimized to account for liabilities relating to in vitro pharmacokinetics, cytotoxicity and protein-related shifts in potency. A representative compound showing favorable in vivo pharmacokinetics was found to be an efficacious inhibitor of 11beta-HSD1 in a rat pharmacodynamic model (ED(50)=10mg/kg).

  14. Renal conservation of ketone bodies during starvation.

    PubMed

    Sapir, D G; Owen, O E

    1975-01-01

    Renal handling of acetoacetate and beta-hydroxybutyrate was studied in 12 obese subjects undergoing total starvation. Simultaneously, the acetoacetate, beta-hydroxybutyrate, and inulin clearance rates were measured, and acetoacetate and beta-hydroxybutyrate reabsorption rates were calculated. Renal clearance of blood acetoacetate and beta-hydroxybutyrate remained constant. In contrast, acetoacetate reabsorption rate increased significantly from 47 plus or minus 10 mumoles/min on day 3 to 106 plus or minus 15, 89 plus or minus 10, and 96 plus or minus 10 mumoles/min on days 10, 17, and 24, respectively. Similarly, beta-hydroxybutyrate reabsorption rate increased significantly from 154 plus or minus 27 mumoles/min on day 3 to 419 plus or minus 53, 399 plus or minus 25, and 436 plus or minus 53 mumoles/min on days 10, 17, and 24, respectively. Both acetoacetate and beta-hydroxybutyrate reabsorption rates increased linearly when plotted against their filtered loads. Thus, no tubular maximal transport rate exists for acetoacetate or beta-hydroxybutyrate during physiologic ketonemia. Conservation 450-500 mmoles of ketone bodies/day prevents large urinary losses of cations during prolonged starvation. Since ammonium becomes the major cation excreted during prolonged fasting, the increased renal reabsorption of ketone bodies minimizes body protein loss and aids in maintaining high circulating acetoacetate and beta-hydroxybutyrate concentrations.

  15. Ketones and Human Performance.

    PubMed

    Scott, Jonathan M; Deuster, Patricia A

    Everyone is seeking nutritional strategies that might benefit performance. One approach receiving much attention is ketones, or ketosis. Ketones are very simple compounds made of hydrogen, carbon, and oxygen, and ketosis is a metabolic state whereby the body uses predominantly ketones. Ketosis can be achieved by fasting for longer than 72 hours or by following a very lowcarbohydrate, high-fat diet (ketogenic diet) for several days to weeks. Alternatively, ketone supplements purportedly induce ketosis rapidly and do not require strict adherence to any specific type of diet; however, much of the touted benefits are anecdotal. A potential role for ketosis as a performance enhancer was first introduced in 1983 with the idea that chronic ketosis without caloric restriction could preserve submaximal exercise capability by sparing glycogen or conserving the limited carbohydrate stores. Few human studies on the effects of a ketogenic diet on performance have yielded positive results, and most studies have yielded equivocal or null results, and a few negative results. Many questions about ketones relevant to Special Operations Forces (SOF) remain unanswered. At present, a ketogenic diet and/or a ketone supplement do not appear confer performance benefits for SOF. Instead, Operators should engage with their unit dietitian to develop individualized nutritional strategies based on unique mission requirements. The authors review the concept of a ketogenic diet, describe some potential benefits and risks of ketosis, review the performance literature and how to measure ketone status, and then summarize the landscape in 2017. 2017.

  16. Synthesis of methyl ketones by metabolically engineered Escherichia coli.

    PubMed

    Park, John; Rodríguez-Moyá, María; Li, Mai; Pichersky, Eran; San, Ka-Yiu; Gonzalez, Ramon

    2012-11-01

    Methyl ketones are a group of highly reduced platform chemicals with widespread applications in the fragrance, flavor and pharmacological industries. Current methods for the industrial production of methyl ketones include oxidation of hydrocarbons, but recent advances in the characterization of methyl ketone synthases from wild tomato have sparked interest towards the development of microbial platforms for the industrial production of methyl ketones. A functional methyl ketone biosynthetic pathway was constructed in Escherichia coli by over-expressing two genes from Solanum habrochaites: shmks2, encoding a 3-ketoacyl-ACP thioesterase, and shmks1, encoding a beta-decarboxylase. These enzymes enabled methyl ketone synthesis from 3-ketoacyl-ACP, an intermediate in the fatty acid biosynthetic cycle. The production of 2-nonanone, 2-undecanone, and 2-tridecanone by MG1655 pTH-shmks2-shmks1 was initially detected by nuclear magnetic resonance and gas chromatography-mass spectrometry analyses at levels close to 6 mg/L. The deletion of major fermentative pathways leading to ethanol (adhE), lactate (ldhA), and acetate (pta, poxB) production allowed for the carbon flux to be redirected towards methyl ketone production, doubling total methyl ketone concentration. Variations in methyl ketone production observed under different working volumes in flask experiments led to a more detailed analysis of the effects of oxygen availability on methyl ketone concentration in order to determine optimal levels of oxygen. The methyl ketone concentration achieved with MG1655 ∆adhE ∆ldhA ∆poxB ∆pta pTrcHis2A-shmks2-shmks1, the best performer strain in this study, was approximately 500 mg/L, the highest reported for an engineered microorganism. Through the establishment of optimal operating conditions and by executing rational metabolic engineering strategies, we were able to increase methyl ketone concentrations by almost 75-fold from the initial confirmatory levels.

  17. Flash-photolytic generation of dienols and dienolates from alpha,beta-unsaturated esters and kinetics of their amine-catalyzed ketonization in nonaqueous media.

    PubMed

    Hénin, Françoise; Létinois, Stéphane; Muzart, Jacques; Wirz, Jakob

    2006-04-01

    Dienols of alpha,beta-unsaturated esters were generated and observed by flash photolysis and their decay rates in acetonitrile and in hexane solutions were measured in the presence of amines or aminoalcohols. In acetonitrile, 1 ratio 1 ammonium dienolate transient intermediates were observed. In hexane, no dienolate could be detected and two moles of the inductor participated in the rate-determining step for tautomerization.

  18. Motion of the Zinc Ions in Catalysis by a di-Zinc Metallo-beta-Lactamase

    SciTech Connect

    R Breece; Z Hu; M Crowder; D Tierney

    2011-12-31

    We report rapid-freeze-quench X-ray absorption spectroscopy of a dizinc metallo-beta-lactamase (MbetaL) reaction intermediate. The Zn(II) ions in the dinuclear active site of the S. maltophilia Class B3 MbetaL move away from each other, by approximately 0.3 A after 10 ms of reaction with nitrocefin, from 3.4 to 3.7 A. Together with our previous characterization of the resting enzyme and its nitrocefin product complex, where the Zn(II) ion separation relaxes to 3.6 A, these data indicate a scissoring motion of the active site that accompanies the ring-opening step. The average Zn(II) coordination number of 4.5 in the resting enzyme appears to be maintained throughout the reaction with nitrocefin. This is the first direct structural information available on early stage dizinc metallo-beta-lactamase catalysis.

  19. Volatilization of ketones

    USGS Publications Warehouse

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

    1984-01-01

    Volatilization fluxes of seven ketones were measured over a range of temperatures. Gas-film coefficients were calculated from these volatilization fluxes and related to the gas-film coefficient for the evaporation of water. These relations, when combined with an equation for estimating the gas-film coefficient for evaporation of water from a canal, permit estimating gas-film coefficients for the volatilization of ketones from streams and rivers.

  20. Oxidative metabolism: glucose versus ketones.

    PubMed

    Prince, Allison; Zhang, Yifan; Croniger, Colleen; Puchowicz, Michelle

    2013-01-01

    The coupling of upstream oxidative processes (glycolysis, beta-oxidation, CAC turnover) to mitochondrial oxidative phosphorylation (OXPHOS) under the driving conditions of energy demand by the cell results in the liberation of free energy as ATP. Perturbations in glycolytic CAC or OXPHOS can result in pathology or cell death. To better understand whole body energy expenditure during chronic ketosis, we used a diet-induced rat model of ketosis to determine if high-fat-carbohydrate-restricted "ketogenic" diet results in changes in total energy expenditure (TEE). Consistent with previous reports of increased energy expenditure in mice, we hypothesized that rats fed ketogenic diet for 3 weeks would result in increased resting energy expenditure due to alterations in metabolism associated with a "switch" in energy substrate from glucose to ketone bodies. The rationale is ketone bodies are a more efficient fuel than glucose. Indirect calorimetric analysis revealed a moderate increase in VO2 and decreased VCO2 and heat with ketosis. These results suggest ketosis induces a moderate uncoupling state and less oxidative efficiency compared to glucose oxidation.

  1. New approach to determination of total ketone bodies in serum.

    PubMed

    Siegel, L; Robin, N I; McDonald, L J

    1977-01-01

    We describe a one-step assay for total ketone bodies in serum. D-BETA-Hydroxybutyrate is enzymatically oxidized by NAD+ to acetoacetate. This thermodynamically unfavorable reaction is driven to completion by coupling it with the enzymatic reduction of pyruvate by NADH. The acetoacetate so formed, as well as the pre-existing acetoacetate, is quantitatively decarboxylated to acetone in a gas chromatograph and measured directly. Thus by a single measurement for acetone, all three ketone bodies are simultaneously determined. In light of the ubiquity of situations associated with augmented ketone body production, the clinical implications of this approach are extensive.

  2. Electrocatalysis of chloroacetic acids (mono-, di- and tri-) at a C60-[dimethyl-(beta-cyclodextrin)]2 and nafion chemically modified electrode.

    PubMed

    Wei, M; Li, M; Li, N; Gu, Z; Zhou, X

    2001-01-26

    The C(60)-[dimethyl-(beta-cyclodextrin)](2) and nafion chemically modified electrode (CME) exhibits one electroreduction peak and two electro-oxidation peaks in a mixed solvent of water and acetonitrile (3:2, v/v) containing tetra-butylammonium perchlorate. The reduction of chloroacetic acids (mono-, di- and tri-) can be electrocatalyzed at this electrode, indicating that C(60)-[dimethyl-(beta-cyclodextrin)](2) is capable of mediating the electron transfer to chloroacetic acids. Values of the apparent catalytic rate constant, k, were determined by using the rotating-disk electrode (RDE).

  3. Di-substituted pyridinyl aminohydantoins as potent and highly selective human beta-secretase (BACE1) inhibitors.

    PubMed

    Malamas, Michael S; Barnes, Keith; Johnson, Matthew; Hui, Yu; Zhou, Ping; Turner, Jim; Hu, Yun; Wagner, Erik; Fan, Kristi; Chopra, Rajiv; Olland, Andrea; Bard, Jonathan; Pangalos, Menelas; Reinhart, Peter; Robichaud, Albert J

    2010-01-15

    The identification of highly selective small molecule di-substituted pyridinyl aminohydantoins as beta-secretase inhibitors is reported. The more potent and selective analogs demonstrate low nanomolar potency for the BACE1 enzyme as measured in a FRET assay, and exhibit comparable activity in a cell-based (ELISA) assay. In addition, these pyridine-aminohydantoins are highly selectivity (>500x) against the other structurally related aspartyl proteases BACE2, cathepsin D, pepsin and renin. Our design strategy followed a traditional SAR approach and was supported by molecular modeling studies based on the previously reported aminohydantoin 3a. We have taken advantage of the amino acid difference between the BACE1 and BACE2 at the S2' pocket (BACE1 Pro(70) changed to BACE2 Lys(86)) to build ligands with >500-fold selectivity against BACE2. The addition of large substituents on the targeted ligand at the vicinity of this aberration has generated a steric conflict between the ligand and these two proteins, thus impacting the ligand's affinity and selectivity. These ligands have also shown an exceptional selectivity against cathepsin D (>5000-fold) as well as the other aspartyl proteases mentioned. One of the more potent compounds (S)-39 displayed an IC(50) value for BACE1 of 10nM, and exhibited cellular activity with an EC(50) value of 130nM in the ELISA assay.

  4. Normalization of the peripheral blood T cell receptor V beta repertoire after cultured postnatal human thymic transplantation in DiGeorge syndrome.

    PubMed

    Davis, C M; McLaughlin, T M; Watson, T J; Buckley, R H; Schiff, S E; Hale, L P; Haynes, B F; Markert, M L

    1997-03-01

    Complete DiGeorge syndrome is an immunodeficiency disease characterized by thymic aplasia and the absence of functioning peripheral T cells. A patient with this syndrome was transplanted with cultured postnatal human thymic tissue. Within 5 weeks of transplantation, flow cytometry, T cell receptor V beta sequence analysis, and cell function studies showed the presence of oligoclonal populations of nonfunctional clonally expanded peripheral T cells that were derived from pretransplantation T cells present in the skin. However, at 3 months posttransplantation, a biopsy of the transplanted thymus showed normal intrathymic T cell maturation of host T cells with normal TCR V beta expression on thymocytes. By 9 months postransplantation, peripheral T cell function was restored and the TCR V beta repertoire became polyclonal, coincident with the appearance of normal T cell function. These data suggest that the transplanted thymus was responsible for the establishment of a new T cell repertoire via thymopoiesis in the chimeric thymic graft.

  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. Methyl isobutyl ketone (MIBK)

    Integrated Risk Information System (IRIS)

    EPA / 635 / R - 03 / 002 TOXICOLOGICAL REVIEW OF METHYL ISOBUTYL KETONE ( CAS No . 108 - 10 - 1 ) In Support of Summary Information on the Integrated Risk Information System ( IRIS ) March 2003 U.S . Environmental Protection Agency Washington DC DISCLAIMER This document has been reviewed in accordan

  7. Ketone body metabolism and its defects.

    PubMed

    Fukao, Toshiyuki; Mitchell, Grant; Sass, Jörn Oliver; Hori, Tomohiro; Orii, Kenji; Aoyama, Yuka

    2014-07-01

    Acetoacetate (AcAc) and 3-hydroxybutyrate (3HB), the two main ketone bodies of humans, are important vectors of energy transport from the liver to extrahepatic tissues, especially during fasting, when glucose supply is low. Blood total ketone body (TKB) levels should be evaluated in the context of clinical history, such as fasting time and ketogenic stresses. Blood TKB should also be evaluated in parallel with blood glucose and free fatty acids (FFA). The FFA/TKB ratio is especially useful for evaluation of ketone body metabolism. Defects in ketogenesis include mitochondrial HMG-CoA synthase (mHS) deficiency and HMG-CoA lyase (HL) deficiency. mHS deficiency should be considered in non-ketotic hypoglycemia if a fatty acid beta-oxidation defect is suspected, but cannot be confirmed. Patients with HL deficiency can develop hypoglycemic crises and neurological symptoms even in adolescents and adults. Succinyl-CoA-3-oxoacid CoA transferase (SCOT) deficiency and beta-ketothiolase (T2) deficiency are two defects in ketolysis. Permanent ketosis is pathognomonic for SCOT deficiency. However, patients with "mild" SCOT mutations may have nonketotic periods. T2-deficient patients with "mild" mutations may have normal blood acylcarnitine profiles even in ketoacidotic crises. T2 deficient patients cannot be detected in a reliable manner by newborn screening using acylcarnitines. We review recent data on clinical presentation, metabolite profiles and the course of these diseases in adults, including in pregnancy.

  8. Sirtuin 3 mediates neuroprotection of ketones against ischemic stroke.

    PubMed

    Yin, Junxiang; Han, Pengcheng; Tang, Zhiwei; Liu, Qingwei; Shi, Jiong

    2015-11-01

    Stroke is one of the leading causes of death. Growing evidence indicates that ketone bodies have beneficial effects in treating stroke, but their underlying mechanism remains unclear. Our previous study showed ketone bodies reduced reactive oxygen species by using NADH as an electron donor, thus increasing the NAD(+)/NADH ratio. In this study, we investigated whether mitochondrial NAD(+)-dependent Sirtuin 3 (SIRT3) could mediate the neuroprotective effects of ketone bodies after ischemic stroke. We injected mice with either normal saline or ketones (beta-hydroxybutyrate and acetoacetate) at 30 minutes after ischemia induced by transient middle cerebral artery (MCA) occlusion. We found that ketone treatment enhanced mitochondria function, reduced oxidative stress, and therefore reduced infarct volume. This led to improved neurologic function after ischemia, including the neurologic score and the performance in Rotarod and open field tests. We further showed that ketones' effects were achieved by upregulating NAD(+)-dependent SIRT3 and its downstream substrates forkhead box O3a (FoxO3a) and superoxide dismutase 2 (SOD2) in the penumbra region since knocking down SIRT3 in vitro diminished ketones' beneficial effects. These results provide us a foundation to develop novel therapeutics targeting this SIRT3-FoxO3a-SOD2 pathway.

  9. Sirtuin 3 mediates neuroprotection of ketones against ischemic stroke

    PubMed Central

    Yin, Junxiang; Han, Pengcheng; Tang, Zhiwei; Liu, Qingwei; Shi, Jiong

    2015-01-01

    Stroke is one of the leading causes of death. Growing evidence indicates that ketone bodies have beneficial effects in treating stroke, but their underlying mechanism remains unclear. Our previous study showed ketone bodies reduced reactive oxygen species by using NADH as an electron donor, thus increasing the NAD+/NADH ratio. In this study, we investigated whether mitochondrial NAD+-dependent Sirtuin 3 (SIRT3) could mediate the neuroprotective effects of ketone bodies after ischemic stroke. We injected mice with either normal saline or ketones (beta-hydroxybutyrate and acetoacetate) at 30 minutes after ischemia induced by transient middle cerebral artery (MCA) occlusion. We found that ketone treatment enhanced mitochondria function, reduced oxidative stress, and therefore reduced infarct volume. This led to improved neurologic function after ischemia, including the neurologic score and the performance in Rotarod and open field tests. We further showed that ketones' effects were achieved by upregulating NAD+-dependent SIRT3 and its downstream substrates forkhead box O3a (FoxO3a) and superoxide dismutase 2 (SOD2) in the penumbra region since knocking down SIRT3 in vitro diminished ketones' beneficial effects. These results provide us a foundation to develop novel therapeutics targeting this SIRT3-FoxO3a-SOD2 pathway. PMID:26058697

  10. A focused review of the role of ketone bodies in health and disease.

    PubMed

    Akram, Muhammad

    2013-11-01

    Ketone bodies are produced in the liver and are utilized in other tissues in the body as an energy source when hypoglycemia occurs in the body. There are three ketone bodies: acetoacetate, beta hydroxy butyrate, and acetone. Ketone bodies are usually present in the blood, and their level increases during fasting and starvation. They are also found in the blood of neonates and pregnant women. In diabetic ketoacidosis, high levels of ketone bodies are produced in response to low insulin levels and high levels of counter-regulatory hormones.

  11. Ketones: metabolism's ugly duckling.

    PubMed

    VanItallie, Theodore B; Nufert, Thomas H

    2003-10-01

    Ketones were first discovered in the urine of diabetic patients in the mid-19th century; for almost 50 years thereafter, they were thought to be abnormal and undesirable by-products of incomplete fat oxidation. In the early 20th century, however, they were recognized as normal circulating metabolites produced by liver and readily utilized by extrahepatic tissues. In the 1920s, a drastic "hyperketogenic" diet was found remarkably effective for treatment of drug-resistant epilepsy in children. In 1967, circulating ketones were discovered to replace glucose as the brain's major fuel during the marked hyperketonemia of prolonged fasting. Until then, the adult human brain was thought to be entirely dependent upon glucose. During the 1990s, diet-induced hyperketonemia was found therapeutically effective for treatment of several rare genetic disorders involving impaired neuronal utilization of glucose or its metabolic products. Finally, growing evidence suggests that mitochondrial dysfunction and reduced bioenergetic efficiency occur in brains of patients with Parkinson's disease (PD) and Alzheimer's disease (AD). Because ketones are efficiently used by mitochondria for ATP generation and may also help protect vulnerable neurons from free radical damage, hyperketogenic diets should be evaluated for ability to benefit patients with PD, AD, and certain other neurodegenerative disorders.

  12. Ketone measurements using dipstick methodology in cats with diabetes mellitus.

    PubMed

    Zeugswetter, F; Pagitz, M

    2009-01-01

    To compare the results of urine and plasma ketone dip test in a group of diabetic cats with possible ketosis or ketoacidosis, using laboratory plasma beta-hydroxybutyrate measurements as the gold standard. According to clinical examinations, plasma beta-hydroxybutyrate measurements and venous blood gas analysis, 54 cats with diabetes mellitus were classified as non-ketotic (n=3), ketotic (n=40) or ketoacidotic (n=11). Plasma and urine acetoacetate concentrations were determined using urine reagent strips. Although there was a significant positive correlation between blood and urine ketone measurements (r=0.695, P<0.001), the results differed significantly (Z=-3.494, P<0.001). Using the differential positive rates, the best cut-off value to detect cats with ketoacidosis was 1.5 mmol/l for urine and 4 mmol/l for plasma. The sensitivity/specificity was 82/95 per cent for urine and 100/88 per cent for plasma, respectively. The urine and plasma ketone dip tests have a different diagnostic accuracy, and results have to be interpreted differently. Because of its high sensitivity, the plasma ketone dip test performs better than the urine ketone dip test to identify cats with impending or established ketoacidosis.

  13. [Chiral separation of five beta-blockers using di-n-hexyl L-tartrate-boric acid complex as mobile phase additive by reversed-phase liquid chromatography].

    PubMed

    Yang, Juan; Wang, Lijuan; Guo, Qiaoling; Yang, Gengliang

    2012-03-01

    A reversed-phase high performance liquid chromatographic (HPLC) method using the di-n-hexyl L-tartrate-boric acid complex as a chiral mobile phase additive was developed for the enantioseparation of five beta-blockers including propranolol, esmolol, metoprolol, bisoprolol and sotalol. In order to obtain a better enantioseparation, the influences of concentrations of di-n-butyl L-tartrate and boric acid, the type, concentration and pH of the buffer, methanol content as well as the molecular structure of analytes were extensively investigated. The separation of the analytes was performed on a Venusil MP-C18 column (250 mm x 4.6 mm, 5 microm). The mobile phase was 15 mmol/L ammonium acetate-methanol containing 60 mmol/L boric acid, 70 mmol/L di-n-hexyl L-tartrate (pH 6.00). The volume ratios of 15 mmol/L ammonium acetate to methanol were 20: 80 for propranolol, esmolol, metoprolol, bisoprolol and 30: 70 for sotalol. The flow rate was 0.5 mL/min and the detection wavelength was set at 214 nm. Under the optimized conditions, baseline enantioseparation was obtained separately for the five pairs of analytes.

  14. Monolayer patterning using ketone dipoles.

    PubMed

    Kim, Min Kyoung; Xue, Yi; Pašková, Tereza; Zimmt, Matthew B

    2013-08-14

    The self-assembly of multi-component monolayers with designed patterns requires molecular recognition among components. Dipolar interactions have been found to influence morphologies of self-assembled monolayers and can affect molecular recognition functions. Ketone groups have large dipole moments (2.6 D) and are easily incorporated into molecules. The potential of ketone groups for dipolar patterning has been evaluated through synthesis of two 1,5-disubstituted anthracenes bearing mono-ketone side chains, STM characterization of monolayers self-assembled from their single and two component solutions and molecular mechanics simulations to determine their self-assembly energetics. The results reveal that (i) anthracenes bearing self-repulsive mono-ketone side chains assemble in an atypical monolayer morphology that establishes dipolar attraction, instead of repulsion, between ketones in adjacent side chains; (ii) pairs of anthracene molecules whose self-repulsive ketone side chains are dipolar complementary spontaneously assemble compositionally patterned monolayers, in which the two components segregate into neighboring, single component columns, driven by side chain dipolar interactions; (iii) compositionally patterned monolayers also assemble from dipolar complementary anthracene pairs that employ different dipolar groups (ketones or CF2 groups) in their side chains; (iv) the ketone group, with its larger dipole moment and size, provides comparable driving force for patterned monolayer formation to that of the smaller dipole, and smaller size, CF2 group.

  15. Cyclic di-AMP targets the cystathionine beta-synthase domain of the osmolyte transporter OpuC.

    PubMed

    Huynh, TuAnh Ngoc; Choi, Philip H; Sureka, Kamakshi; Ledvina, Hannah E; Campillo, Julian; Tong, Liang; Woodward, Joshua J

    2016-10-01

    Cellular turgor is of fundamental importance to bacterial growth and survival. Changes in external osmolarity as a consequence of fluctuating environmental conditions and colonization of diverse environments can significantly impact cytoplasmic water content, resulting in cellular lysis or plasmolysis. To ensure maintenance of appropriate cellular turgor, bacteria import ions and small organic osmolytes, deemed compatible solutes, to equilibrate cytoplasmic osmolarity with the extracellular environment. Here, we show that elevated levels of c-di-AMP, a ubiquitous second messenger among bacteria, result in significant susceptibility to elevated osmotic stress in the bacterial pathogen Listeria monocytogenes. We found that levels of import of the compatible solute carnitine show an inverse correlation with intracellular c-di-AMP content and that c-di-AMP directly binds to the CBS domain of the ATPase subunit of the carnitine importer OpuC. Biochemical and structural studies identify conserved residues required for this interaction and transport activity in bacterial cells. Overall, these studies reveal a role for c-di-AMP mediated regulation of compatible solute import and provide new insight into the molecular mechanisms by which this essential second messenger impacts bacterial physiology and adaptation to changing environmental conditions. © 2016 John Wiley & Sons Ltd.

  16. 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

  17. 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

  18. Photoreactivity of. cap alpha. -fluorinated phenyl alkyl ketones

    SciTech Connect

    Wagner, P.J.; Thomas, M.J.; Puchalski, A.E.

    1986-11-26

    The photoreactivities of the mono-, di-, and tri-..cap alpha..-fluorinated acetophenones have been compared to that of acetophenone itself. All four ketones have similar triplet excitation energies; the three fluorinated ketones have reduction potentials 0.5-0.7 eV lower than that of acetophenone. Triplet reactivity toward alkylbenzenes keeps increasing with fluorine substitution, since the rate-determining step becomes charge-transfer complexation as the ketone reduction potential decreases. The primary/tertiary C-H selectivity toward p-cymene increases with the number of fluorines. Triplet reactivity toward cyclopentane also is increased by fluorination but peaks at two fluorines, since the lowest triplet switches from n,..pi..* to ..pi..,..pi..* with two or three fluorines and ..pi..,..pi..* triplets are unreactive in simple hydrogen atom abstraction. In contrast, ..cap alpha..-fluorination of valerophenone does not significantly increase the rate of triplet ..gamma..-hydrogen abstraction. The inductive effect on reactivity apparently is offset by a conformational effect. The ..cap alpha..-fluorinated phenones give predominantly cyclobutanols instead of Norrish type II elimination. ..cap alpha..-Fluoroacetophenone forms predominantly acetophenone and HF when irradiated with 2-propanol, in what appears to be a short chain process involving electron transfer to ketone followed by fluoride ion loss. Finally, the radical coupling products in these reactions are formed in varying yields, depending on solvent and additives.

  19. ESR, electrochemical and cyclodextrin-inclusion studies of triazolopyridyl pyridyl ketones and dipyridyl ketones derivatives.

    PubMed

    Olea-Azar, C; Abarca, B; Norambuena, E; Opazo, L; Jullian, C; Valencia, S; Ballesteros, R; Chadlaoui, M

    2008-11-15

    The electron spin resonance (ESR) spectra of free radicals obtained by electrolytic reduction of triazolopyridyl pyridyl ketones and dipyridyl ketones derivatives were measured in dimethylsulfoxide (DMSO). The hyperfine patterns indicate that the spin density delocalization is dependent of the rings presented in the molecule. The electrochemistry of these compounds was characterized using cyclic voltammetry, in DMSO as solvent. When one carbonyl is present in the molecule one step in the reduction mechanism was observed while two carbonyl are present two steps were detected. The first wave was assigned to the generation of the correspondent free radical species, and the second wave was assigned to the dianion derivatives. The phase-solubility measurements indicated an interaction between molecules selected and cyclodextrins in water. These inclusion complexes are 1:1 with betaCD, and HP-betaCD. The values of Ks showed a different kind of complexes depending on which rings are included. AM1 and DFT calculations were performed to obtain the optimized geometries, theoretical hyperfine constants, and spin distributions, respectively. The theoretical results are in complete agreement with the experimental ones.

  20. A ketogenic diet increases transport and oxidation of ketone bodies in RG2 and 9L gliomas without affecting tumor growth

    PubMed Central

    De Feyter, Henk M.; Behar, Kevin L.; Rao, Jyotsna U.; Madden-Hennessey, Kirby; Ip, Kevan L.; Hyder, Fahmeed; Drewes, Lester R.; Geschwind, Jean-François; de Graaf, Robin A.; Rothman, Douglas L.

    2016-01-01

    Background The dependence of tumor cells, particularly those originating in the brain, on glucose is the target of the ketogenic diet, which creates a plasma nutrient profile similar to fasting: increased levels of ketone bodies and reduced plasma glucose concentrations. The use of ketogenic diets has been of particular interest for therapy in brain tumors, which reportedly lack the ability to oxidize ketone bodies and therefore would be starved during ketosis. Because studies assessing the tumors' ability to oxidize ketone bodies are lacking, we investigated in vivo the extent of ketone body oxidation in 2 rodent glioma models. Methods Ketone body oxidation was studied using 13C MR spectroscopy in combination with infusion of a 13C-labeled ketone body (beta-hydroxybutyrate) in RG2 and 9L glioma models. The level of ketone body oxidation was compared with nontumorous cortical brain tissue. Results The level of 13C–beta-hydroxybutyrate oxidation in 2 rat glioma models was similar to that of contralateral brain. In addition, when glioma-bearing animals were fed a ketogenic diet, the ketone body monocarboxylate transporter was upregulated, facilitating uptake and oxidation of ketone bodies in the gliomas. Conclusions These results demonstrate that rat gliomas can oxidize ketone bodies and indicate upregulation of ketone body transport when fed a ketogenic diet. Our findings contradict the hypothesis that brain tumors are metabolically inflexible and show the need for additional research on the use of ketogenic diets as therapy targeting brain tumor metabolism. PMID:27142056

  1. Antioxidant effects of isorhamnetin 3,7-di-O-beta-D-glucopyranoside isolated from mustard leaf (Brassica juncea) in rats with streptozotocin-induced diabetes.

    PubMed

    Yokozawa, Takako; Kim, Hyun Young; Cho, Eun Ju; Choi, Jae Sue; Chung, Hae Young

    2002-09-11

    To investigate the effects of isorhamnetin 3,7-di-O-beta-D-glucopyranoside (isorhamnetin diglucoside), a major flavonoid compound of mustard leaf, on oxidative stress due to diabetes mellitus, in vivo and in vitro studies were carried out. Oral administration of isorhamnetin diglucoside (10 or 20 mg/kg of body weight/day for 10 days) to rats with streptozotocin-induced diabetes significantly reduced serum levels of glucose and 5-(hydroxymethyl)furfural (5-HMF), which is glycosylated with hemoglobin and is an indicator of oxidative stress. After intraperitoneal administration, isorhamnetin diglucoside did not show these activities. In addition, after oral administration, the thiobarbituric acid-reactive substance levels of serum, and liver and kidney mitochondria declined significantly compared with the control group in a dose-dependent manner, whereas after intraperitoneal administration these levels fell only slightly. On the basis of the oral and intraperitoneal results, it was hypothesized that isorhamnetin diglucoside was converted to its metabolite in vivo, and its conversion to its aglycone, isorhamnetin, by beta-glucosidase was confirmed; isorhamnetin acted as an antioxidant. Moreover, it was observed that isorhamnetin diglucoside had no effect on the 1,1-diphenyl-2-picrylhydrazyl radical, whereas isorhamnetin showed a potent antioxidant effect in vitro. In addition, intraperitoneal administration of isorhamnetin reduced serum glucose and 5-HMF levels. Furthermore, lipid peroxidation in blood, liver, and kidney associated with diabetes mellitus declined after the administration of isorhamnetin. These results suggest that isorhamnetin diglucoside is metabolized in vivo by intestinal bacteria to isorhamnetin and that isorhamnetin plays an important role as an antioxidant.

  2. Value of point-of-care ketones in assessing dehydration and acidosis in children with gastroenteritis.

    PubMed

    Levy, Jason A; Waltzman, Mark; Monuteaux, Michael C; Bachur, Richard G

    2013-11-01

    Children with gastroenteritis often develop dehydration with metabolic acidosis. Serum ketones are frequently elevated in this population. The goal was to determine the relationship between initial serum ketone concentration and both the degree of dehydration and the magnitude of acidosis. This was a secondary analysis of a prospective trial of crystalloid administration for rapid rehydration. Children 6 months to 6 years of age with gastroenteritis and dehydration were enrolled. A point-of-care serum ketone (beta-hydroxybutyrate) concentration was obtained at the time of study enrollment. The relationship between initial serum ketone concentration and a prospectively assigned and previously validated clinical dehydration score, and serum bicarbonate concentration, was analyzed. A total of 188 patients were enrolled. The median serum ketone concentration was elevated at 3.1 mmol/L (interquartile range [IQR] = 1.2 to 4.6 mmol/L), and the median dehydration score was consistent with moderate dehydration. A significant positive relationship was found between serum ketone concentration and the clinical dehydration score (Spearman's rho = 0.22, p = 0.003). Patients with moderate dehydration had a higher median serum ketone concentration than those with mild dehydration (3.6 mmol/L vs. 1.4 mmol/L, p = 0.007). Additionally, the serum ketone concentration was inversely correlated with serum bicarbonate concentration (ρ = -0.26, p < 0.001). Children with gastroenteritis and dehydration have elevated serum ketone concentrations that correlate with both degree of dehydration and magnitude of metabolic acidosis. Point-of-care serum ketone measurement may be a useful tool to inform management decisions at the point of triage or in the initial evaluation of children with gastroenteritis and dehydration. © 2013 by the Society for Academic Emergency Medicine.

  3. Conformation of di-n-propylglycine residues (Dpg) in peptides: crystal structures of a type I' beta-turn forming tetrapeptide and an alpha-helical tetradecapeptide.

    PubMed

    Hegde, Raghurama P; Aravinda, Subrayashastry; Rai, Rajkishor; Kaul, Ramesh; Vijayalakshmi, Sarojini; Rao, R Balaji; Shamala, Narayanaswamy; Balaram, Padmanabhan

    2008-05-01

    The crystal structures of two oligopeptides containing di-n-propylglycine (Dpg) residues, Boc-Gly-Dpg-Gly-Leu-OMe (1) and Boc-Val-Ala-Leu-Dpg-Val-Ala-Leu-Val-Ala-Leu-Dpg-Val-Ala-Leu-OMe (2) are presented. Peptide 1 adopts a type I'beta-turn conformation with Dpg(2)-Gly(3) at the corner positions. The 14-residue peptide 2 crystallizes with two molecules in the asymmetric unit, both of which adopt alpha-helical conformations stabilized by 11 successive 5 --> 1 hydrogen bonds. In addition, a single 4 --> 1 hydrogen bond is also observed at the N-terminus. All five Dpg residues adopt backbone torsion angles (phi, psi) in the helical region of conformational space. Evaluation of the available structural data on Dpg peptides confirm the correlation between backbone bond angle N-C(alpha)-C' (tau) and the observed backbone phi,psi values. For tau > 106 degrees, helices are observed, while fully extended structures are characterized by tau < 106 degrees. The mean tau values for extended and folded conformations for the Dpg residue are 103.6 degrees +/- 1.7 degrees and 109.9 degrees +/- 2.6 degrees, respectively.

  4. Volatilization of ketones from water

    USGS Publications Warehouse

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

    1982-01-01

    The overall mass-transfer coefficients for the volatilization from water of acetone, 2-butanone, 2-pentanone, 3-pentanone, 4-methyl-2-pentanone, 2-heptanone, and 2-octanone were measured simultaneously with the oxygen-absorption coefficient in a laboratory stirred water bath. The liquid-film and gas-film coefficients of the two-film model were determined for the ketones from the overall coefficients, and both film resistances were important for volatilization of the ketones.The liquid-film coefficients for the ketones varied with the 0.719 power of the molecular-diffusion coefficient, in agreement with the literature. The liquid-film coefficients showed a variable dependence on molecular weight, with the dependence ranging from the −0.263 power for acetone to the −0.378 power for 2-octanone. This is in contrast with the literature where a constant −0.500 power dependence on the molecular weight is assumed.The gas-film coefficients for the ketones showed no dependence on molecular weight, in contrast with the literature where a −0.500 power is assumed.

  5. 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.

  6. 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

  7. Ketone production in ultra marathon runners.

    PubMed

    Weibel, J; Glonek, T

    2007-12-01

    The aim of this study was to determine the magnitude of ketone production in ultra marathon runners and what affect if any this has on performance. Participants in the Cliff Young Australian Six Day Race (n=31) provided a prerace urine sample and, then, random urine samples throughout the duration of the event, ranging from 4-20 samples each. Based on urinalysis results, participants were divided into two groups: those who formed ketones (ketone group), and those who did not form ketones or formed ketones only once during a race at the lowest recordable value (non-ketone group). The average ketone level of the 22 athletes in the ketone group (value+/-standard deviation: 5.67+/-5.59 mg/dL) was statistically different from 9 athletes who were in the non-ketone group (0.18+/-0.14 mg/dL) (P<0.05). The average distances run for the two groups were 498.09+/-153.99 and 535.6+/-181.08 km, respectively (P=0.56). When average ketone value was compared, excluding runners who did not complete the race, the ketone group (5.88+/-1.37) remained statistically different from the non-ketone group (0.2+/-0.45) (P<0.05). The average distances for those athletes who completed the race were 583.9+/-116.09 and 557.8+/-85.82 km, respectively (P=0.52). We conclude that although two runner sub-populations were revealed, runners who produce ketones and runners who do not make ketones, the level of ketones produced did not affect overall distance run, which is the performance criterion of the race. The nature of this extreme event has illuminated a physiologic difference among ultra marathon runners, and although this difference does not appear to affect race performance, the long-term health consequences are unknown and additional rigorous research is warranted.

  8. Enzymic synthesis of di- and tri-saccharide glycosides, using glycosidases and beta-D-galactoside 3-alpha-sialyl-transferase.

    PubMed

    Nilsson, K G

    1989-06-01

    The following disaccharide glycosides were obtained in yields of 10-35% from the appropriate donor and acceptor glycosides by employing glycosidases as catalysts: alpha-D-Galp-(1----3)-alpha-D-GalpNAc-OEt (alpha-D-galactosidase), beta-D-Galp-(1----3)-alpha-D-GalpNAc-OEt and beta-D-Galp-(1----3)-beta-D-GalpNAc-OEtBr (beta-D-galactosidase), beta-D-GlcpNAc-(1----6)-beta-D-Galp-OMe and beta-D-GlcpNAc-(1----6)-alpha-D-Manp-OMe (beta-N-acetylglucosaminidase). With beta-D-GlcpNAc-OEtSiMe3 as the acceptor, beta-D-galactosidase gave beta-D-Galp-(1----3)-beta-D-GlcpNAc-OEtSiMe3 almost exclusively, whereas, with beta-D-GlcpNAc-OMe as the acceptor, beta-D-Galp-(1----3)-beta-D-GlcpNAc-OMe was formed in only slightly excess over teh analogous beta-(1----4)-linked glycoside. The use of beta-D-galactosidase and beta-D-galactoside 3-alpha-sialyltransferase in sequence provided a convenient route to the trisaccharide glycosides alpha-D-Neup5Ac-(2----3)-beta-D-Galp-(1----3)-alpha-D-GalpNAc-OEt, alpha-D-Neup5Ac-(2----3)-beta-D-Galp-(1----3)-beta-D-GalpNAc-OE tBr, and alpha-D-Neup5Ac-(2----3)-beta-D-Galp-(1----3)-beta-D-GlcpNAc-OMe.

  9. Solvent influence on the infrared spectra of beta-alkoxyvinyl methyl ketones II. Stretching vibrations and integrated intensities of carbonyl and vinyl bands of (3Z,E)-4-ethoxy-1,1,1-trifluoro-5,5-dimethylhex-3-en-2-one.

    PubMed

    Vdovenko, Sergey I; Gerus, Igor I; Kukhar, Valery P

    2009-03-01

    Infrared spectroscopy studies of beta-alkoxyvinyl trifluoromethyl ketone, with structure C(2)H(5)O-C(C(CH(3))(3))CH-COCF(3) (1), in twenty three different pure organic solvents were undertaken to investigate the solvent-solute interactions and to correlate solvent properties such as Reichard's parameter and solvatochromic parameters of Kamlet, Abbot, and Taft with carbonyl and vinyl stretching vibrations and their integrated intensities of existing spatial forms. It was shown that conjugation in CC-CO system of the (E-s-Z-o-Z) stereoisomer is higher than that in this system of the (Z-s-Z-o-Z) stereoisomer. From derived correlations of the v (CO) and v (CC) wavenumbers with solvatochromic parameters of Kamlet, Abbot, and Taft it is followed that the solvent polarity influences on the v (CO) and v (CC) wavenumbers more intense than the solvent HBD acidity, and, at the same time, the influence of these solvent properties is greater for the (E-s-Z-o-Z) stereoisomer. Analysis of derived KAT multiple regressions showed that the increase of the solvent polarity/polarizability (pi*) increased the conjugation in both stereoisomers, whereas the increase of the solvent HBD acidity (alpha) had opposite effect on conjugation in the (Z-s-Z-o-Z) and (E-s-Z-o-Z) stereoisomer. In the former case conjugation was weakened, whereas in the latter it was enhanced. These discrepancies were the consequence of different structure of H-bonded complexes between enone 1 and HBD solvents. The influence of the solvent HBA basicity (beta) also had peculiarity. The increase of the solvent HBA basicity disturbs the CC-CO conjugation in the (Z-s-Z-o-Z) stereoisomer due to carbonyl rotation, whereas in the (E-s-Z-o-Z) stereoisomer such increase enhanced this conjugation and, hence, increased the v (CO) and v (C==C) coupling.

  10. Silica gel promotes reductions of aldehydes and ketones by N-heterocyclic carbene boranes.

    PubMed

    Taniguchi, Tsuyoshi; Curran, Dennis P

    2012-09-07

    N-Heterocyclic carbene boranes (NHC-boranes) such as 1,3-dimethylimidazol-2-ylidine trihydridoborane (diMe-Imd-BH(3)) serve as practical hydride donors for the reduction of aldehydes and ketones in the presence of silica gel. Primary and secondary alcohols are formed in good yields under ambient conditions. Aldehydes are selectively reduced in the presence of ketones. One, two, or even all three of the boron hydrides can be transferred. The process is attractive because all the components are stable and easy to handle and because both the reaction and isolation procedures are convenient.

  11. 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

  12. 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)

  13. 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. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Cerebral ketone metabolism during development and injury.

    PubMed

    Prins, Mayumi L

    2012-07-01

    Cerebral metabolism of ketones is a normal part of the process of brain development. While the mature brain relies on glucose as a primary fuel source, metabolism of ketone bodies remains an alternative energy source under conditions of starvation. The neuroprotective properties of brain ketone metabolism make this alternative substrate a viable therapeutic option for various pathologies. Since the ability to revert to utilizing ketones as an alternative substrate is greatest in the younger post-weaned brain, this particular therapeutic approach remains an untapped resource particularly for pediatric pathological conditions. Published by Elsevier B.V.

  15. Cerebral Ketone Metabolism During Development and Injury

    PubMed Central

    Prins, Mayumi L.

    2011-01-01

    Cerebral metabolism of ketones is a normal part of the process of brain development. While the mature brain relies on glucose as a primary fuel source, metabolism of ketone bodies remains an alternative energy source under conditions of starvation. The neuroprotective properties of brain ketone metabolism make this alternative substrate a viable therapeutic option for various pathologies. Since the ability to revert to utilizing ketones as an alternative substrate is greatest in the younger post-weaned brain, this particular therapeutic approach remains an untapped resource particularly for pediatric pathological conditions. PMID:22104087

  16. Altered ketone body metabolism during gram-negative sepsis in the rat.

    PubMed

    Lanza-Jacoby, S; Rosato, E; Braccia, G; Tabares, A

    1990-11-01

    To investigate why blood ketone bodies are depressed during sepsis, the production and utilization of ketone bodies was studied in fasted control, fasted, Escherichia coli-treated, fed control, and fed E coli-treated rats. Gram-negative sepsis was induced by intravenous (IV) injection of 8 x 10(7) live colonies of E coli per 100 g body weight. Food was removed from the fasted rats after E coli injection. Fed rats were infused intragastrically with a nutritionally adequate diet for 5 days before inducing sepsis. Twenty-four hours after E coli injection, blood ketone bodies were reduced in fasted septic rats and fed septic rats compared with their respective control rats. Ketogenesis and oxidation of labeled palmitate was not altered in hepatocytes from fasted E coli-treated rats. Yet, ketogenesis declined significantly in hepatocytes from fed E coli-treated rats. Oxidation of labeled palmitate was also significantly reduced in hepatocytes from fed E coli-treated rats. Utilization of ketone bodies as measured by the incorporation of [3-14C]beta-hydroxybutyrate into CO2, increased over threefold in the diaphragm, 12% in the heart, and 19% in the kidneys from the fasted E coli-treated rats. In the fed state, incorporation of [3-14C]beta-hydroxybutyrate into CO2 was elevated fivefold in the heart, fourfold in the diaphragm, and over threefold in the kidneys from the septic rats. These results suggest that in the fasted state, plasma ketone bodies remain low during gram-negative sepsis because peripheral tissues use more ketone bodies and because liver ketogenesis is not increased to compensate for the increased utilization. In the fed state, the reduction in blood ketone bodies appears to be attributed to both impaired ketogenic capacity and increased peripheral utilization.

  17. GNB1L, a gene deleted in the critical region for DiGeorge syndrome on 22q11, encodes a G-protein beta-subunit-like polypeptide.

    PubMed

    Gong, L; Liu, M; Jen, J; Yeh, E T

    2000-11-15

    CATCH 22 syndromes, which include DiGeorge syndrome and Velocardiofacial syndrome, are the most common cause of congenital heart disease which involve microdeletion of 22q11. Using a strategy including EST searching, PCR amplification and 5'-RACE, we have cloned a 1487 bp cDNA fragment from human heart cDNA library. The cloned GNB1L cDNA encodes a G-protein beta-subunit-like polypeptide, and the GNB1L gene is located in the critical region for DiGeorge syndrome. A comparison of GNB1L cDNA sequence with corresponding genomic DNA sequence revealed that this gene consists of seven exons and spans an approximately 60 kb genomic region. Northern blot analysis revealed GNB1L is highly expressed in the heart.

  18. A Convergent Radical Based Route to Trifluoromethyl Ketones and to α,β-Unsaturated Trifluoromethyl Ketones.

    PubMed

    Anthore, Lucile; Zard, Samir Z

    2015-06-19

    A convergent synthesis of trifluoromethyl ketones and α,β-unsaturated trifluoromethyl ketones is described, starting with aliphatic iodides and dithiocarbonates (xanthates) and exploiting both the α- and β-fragmentations of a sulfonyl radical. The transformation initially furnishes the ketones in a masked enol carbonate form, from which they can be easily regenerated.

  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. 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.

  1. Mild electrophilic trifluoromethylthiolation of ketones with trifluoromethanesulfanamide.

    PubMed

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

    2015-07-07

    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.

  2. Clinical review: ketones and brain injury.

    PubMed

    White, Hayden; Venkatesh, Balasubramanian

    2011-04-06

    Although much feared by clinicians, the ability to produce ketones has allowed humans to withstand prolonged periods of starvation. At such times, ketones can supply up to 50% of basal energy requirements. More interesting, however, is the fact that ketones can provide as much as 70% of the brain's energy needs, more efficiently than glucose. Studies suggest that during times of acute brain injury, cerebral uptake of ketones increases significantly. Researchers have thus attempted to attenuate the effects of cerebral injury by administering ketones exogenously. Hypertonic saline is commonly utilized for management of intracranial hypertension following cerebral injury. A solution containing both hypertonic saline and ketones may prove ideal for managing the dual problems of refractory intracranial hypertension and low cerebral energy levels. The purpose of the present review is to explore the physiology of ketone body utilization by the brain in health and in a variety of neurological conditions, and to discuss the potential for ketone supplementation as a therapeutic option in traumatic brain injury.

  3. Clinical review: Ketones and brain injury

    PubMed Central

    2011-01-01

    Although much feared by clinicians, the ability to produce ketones has allowed humans to withstand prolonged periods of starvation. At such times, ketones can supply up to 50% of basal energy requirements. More interesting, however, is the fact that ketones can provide as much as 70% of the brain's energy needs, more efficiently than glucose. Studies suggest that during times of acute brain injury, cerebral uptake of ketones increases significantly. Researchers have thus attempted to attenuate the effects of cerebral injury by administering ketones exogenously. Hypertonic saline is commonly utilized for management of intracranial hypertension following cerebral injury. A solution containing both hypertonic saline and ketones may prove ideal for managing the dual problems of refractory intracranial hypertension and low cerebral energy levels. The purpose of the present review is to explore the physiology of ketone body utilization by the brain in health and in a variety of neurological conditions, and to discuss the potential for ketone supplementation as a therapeutic option in traumatic brain injury. PMID:21489321

  4. Storage stability of ketones on carbon adsorbents.

    PubMed

    Prado, C; Alcaraz, M J; Fuentes, A; Garrido, J; Periago, J F

    2006-09-29

    Activated coconut carbon constitutes the more widely used sorbent for preconcentration of volatile organic compounds in sampling workplace air. Water vapour is always present in the air and its adsorption on the activated carbon surface is a serious drawback, mainly when sampling polar organic compounds, such as ketones. In this case, the recovery of the compounds diminishes; moreover, ketones can be decomposed during storage. Synthetic carbons contain less inorganic impurities and have a lower capacity for water adsorption than coconut charcoal. The aim of this work was to evaluate the storage stability of various ketones (acetone, 2-butanone, 4-methyl-2-pentanone and cyclohexanone) on different activated carbons and to study the effect of adsorbed water vapour under different storage conditions. The effect of storage temperature on extraction efficiencies was significant for each ketone in all the studied sorbents. Recovery was higher when samples were stored at 4 degrees C. The results obtained for storage stability of the studied ketones showed that the performance of synthetic carbons was better than for the coconut charcoals. The water adsorption and the ash content of the carbons can be a measure of the reactive sites that may chemisorb ketones or catalize their decomposition. Anasorb 747 showed good ketone stability at least for 7 days, except for cyclohexanone. After 30-days storage, the stability of the studied ketones was excellent on Carboxen 564. This sorbent had a nearly negligible ash content and the adsorbed water was much lower than for the other sorbents tested.

  5. 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.

  6. A ketogenic diet increases transport and oxidation of ketone bodies in RG2 and 9L gliomas without affecting tumor growth.

    PubMed

    De Feyter, Henk M; Behar, Kevin L; Rao, Jyotsna U; Madden-Hennessey, Kirby; Ip, Kevan L; Hyder, Fahmeed; Drewes, Lester R; Geschwind, Jean-François; de Graaf, Robin A; Rothman, Douglas L

    2016-08-01

    The dependence of tumor cells, particularly those originating in the brain, on glucose is the target of the ketogenic diet, which creates a plasma nutrient profile similar to fasting: increased levels of ketone bodies and reduced plasma glucose concentrations. The use of ketogenic diets has been of particular interest for therapy in brain tumors, which reportedly lack the ability to oxidize ketone bodies and therefore would be starved during ketosis. Because studies assessing the tumors' ability to oxidize ketone bodies are lacking, we investigated in vivo the extent of ketone body oxidation in 2 rodent glioma models. Ketone body oxidation was studied using (13)C MR spectroscopy in combination with infusion of a (13)C-labeled ketone body (beta-hydroxybutyrate) in RG2 and 9L glioma models. The level of ketone body oxidation was compared with nontumorous cortical brain tissue. The level of (13)C-beta-hydroxybutyrate oxidation in 2 rat glioma models was similar to that of contralateral brain. In addition, when glioma-bearing animals were fed a ketogenic diet, the ketone body monocarboxylate transporter was upregulated, facilitating uptake and oxidation of ketone bodies in the gliomas. These results demonstrate that rat gliomas can oxidize ketone bodies and indicate upregulation of ketone body transport when fed a ketogenic diet. Our findings contradict the hypothesis that brain tumors are metabolically inflexible and show the need for additional research on the use of ketogenic diets as therapy targeting brain tumor metabolism. © The Author(s) 2016. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  7. Selective Reductions. 46. Effect of the Steric Requirement at the 2- Position of Apopinene on Chiral Reductions. B-Iso-2-n-Propylapopinocampheyl-9- Borabicyclo(3.3.1)Nonane as Improved Reagents for the Chiral Reduction of Alpha, Beta-Acetylenic Ketones and Alpha-Keto Esters

    DTIC Science & Technology

    1991-01-17

    prepared in situ from methyllithium and cuprous iodide. (+)-2-n-Propylapopinene was synthesized by Schlosser metallation of (+)-ac- pinene followed by...into its components, ac- pinene and 9-BBN with the less reactive ketones resultingo iuAchiral reduction.8 The dehydroboration is suppressed by...cc- pinene . 10 A comparison-of the enantiomeric e cesses of the product alcohols obtained from the reduction of prochiral’acetylenic ketones showsthat 2

  8. Study of ketone body kinetics in children by a combined perfusion of /sup 13/C and /sup 2/H3 tracers

    SciTech Connect

    Bougneres, P.F.; Ferre, P.

    1987-11-01

    Ketone body kinetics were quantified in six children (3-5 yr old), who were fasted for 13-22 h, by a combined perfusion of (3-/sup 13/C)acetoacetate ((/sup 13/C)AcAc) and D-(-)-beta-(4,4,4-/sup 2/H3)hydroxybutyrate (beta-(/sup 2/H3)OHB) and gas chromatography-mass spectrometry analysis. Results were analyzed according to the single-pool (combined enrichments) or the two-accessible pools models. After 20-22 h of fasting, ketone body turnover rate was 30-50 mumol.kg-1.min-1, a rate achieved after several days of fasting in adults. At low ketosis, acetoacetate was the ketone body preferentially synthesized de novo and utilized irreversibly. When ketosis increased, acetoacetate irreversible disposal was not enhanced, since it was largely converted into beta-OHB, whereas beta-OHB irreversible disposal was very much increased. The single-pool and two-pool models gave similar ketone body turnover rates when (/sup 13/C)AcAc was the tracer, whereas the use of beta-(/sup 2/H3)OHB gave some more divergent results, especially at low ketosis. These studies demonstrate that ketogenesis is very active in short-term fasted children and that the use of a combined infusion of (/sup 13/C)AcAc and beta-(/sup 2/H3)OHB is a convenient way to give insight into individual ketone body kinetics.

  9. 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

  10. Organocatalytic asymmetric conjugate addition to allenic esters and ketones.

    PubMed

    Elsner, Petteri; Bernardi, Luca; Dela Salla, Giorgio; Overgaard, Jacob; Jørgensen, Karl Anker

    2008-04-09

    The first example of an organocatalytic enantioselective conjugate addition of cyclic beta-ketoesters and glycine imine derivatives to electron-deficient allenes is described. We disclose that the corresponding chiral beta,gamma-unsaturated carbonyl compounds are formed exclusively under phase-transfer conditions using either cinchona-alkaloid-derived or biphenyl-based chiral quaternary ammonium salts as catalysts. The scope of the reaction for beta-ketoesters is outlined for allenes having a ketone or ester motif as electron-withdrawing group as well as different substituents in the 3-position, giving the optically active products in high yields and excellent diastereo- and enantioselectivities (90-96% ee). The conjugate addition also proceeds for a number of cyclic beta-ketoesters having different ring sizes, ring systems, and substituents in high yields and enantioselectivities. Glycine imine derivatives also undergo the asymmetric conjugate addition to electron-deficient allenes in high yields and with enantioselectivities in the range of 60-88% ee, thus providing a rapid entry to optically active alpha-vinyl-substituted alpha-amino acid derivatives. It is shown that the enantioselectivity is strongly dependent on the size of the ester moiety of the nucleophile in combination with the catalytic system used. The high synthetic value of the chiral products arising from these new catalytic processes is demonstrated by two straightforward transformations leading in one case to optically active hexahydrobenzopyranones and in the other to substituted pyroglutamates (gamma-lactames).

  11. Homologation Reaction of Ketones with Diazo Compounds.

    PubMed

    Candeias, Nuno R; Paterna, Roberta; Gois, Pedro M P

    2016-03-09

    This review covers the addition of diazo compounds to ketones to afford homologated ketones, either in the presence or in the absence of promoters or catalysts. Reactions with diazoalkanes, aryldiazomethanes, trimethylsilyldiazomethane, α-diazo esters, and disubstituted diazo compounds are covered, commenting on the complex regiochemistry of the reaction and the nature of the catalysts and promoters. The recent reports on the enantioselective version of ketone homologation reactions are gathered in one section, followed by reports on the use of cyclic ketones ring expansion in total synthesis. Although the first reports of this reaction appeared in the literature almost one century ago, the recent achievements, in particular, for the asymmetric version, forecast the development of new breakthroughs in the synthetically valuable field of diazo chemistry.

  12. Iodine promoted α-hydroxylation of ketones.

    PubMed

    Siddaraju, Yogesh; Prabhu, Kandikere Ramaiah

    2015-06-28

    A novel method for α-hydroxylation of ketones using substoichiometric amount of iodine under metal-free conditions is described. This method has been successfully employed in synthesizing a variety of heterocyclic compounds, which are useful precursors. α-Hydroxylation of diketones and triketones are illustrated. This strategy provides a novel, efficient, mild and inexpensive method for α-hydroxylation of aryl ketones using a sub-stoichiometric amount of molecular iodine.

  13. Benzoyl radicals from (hetero)aromatic aldehydes. Decatungstate photocatalyzed synthesis of substituted aromatic ketones.

    PubMed

    Ravelli, Davide; Zema, Michele; Mella, Mariella; Fagnoni, Maurizio; Albini, Angelo

    2010-09-21

    Benzoyl radicals are generated directly from (hetero)aromatic aldehydes upon tetrabutylammonium decatungstate ((n-Bu(4)N)(4)W(10)O(32)), TBADT) photocatalysis under mild conditions. In the presence of alpha,beta-unsaturated esters, ketones and nitriles radical conjugate addition ensues and gives the corresponding beta-functionalized aryl alkyl ketones in moderate to good yields (stereoselectively in the case of 3-methylene-2-norbornanone). Due to the mild reaction conditions the presence of various functional groups on the aromatic ring is tolerated (e.g. methyl, methoxy, chloro). The method can be applied to hetero-aromatic aldehydes whether electron-rich (e.g. thiophene-2-carbaldehyde) or electron-poor (e.g. pyridine-3-carbaldehyde).

  14. 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

  15. Rhodium-catalyzed acyl-transfer reaction between benzyl ketones and thioesters: synthesis of unsymmetric ketones by ketone CO-C bond cleavage and intermolecular rearrangement.

    PubMed

    Arisawa, Mieko; Kuwajima, Manabu; Toriyama, Fumihiko; Li, Guangzhe; Yamaguchi, Masahiko

    2012-07-20

    In the presence of catalytic amounts of RhH(CO)(PPh3)3 and 1,2-bis(diphenylphosphino)benzene (dppBz), acyl groups were transferred between benzyl ketones and thioesters/aryl esters. The rhodium complex catalyzed the cleavage of ketone CO-C bonds and intermolecular rearrangement giving unsymmetric ketones. The acyl-transfer reaction also occurred with 1-(p-chlorophenyl)-3-(p-cyanophenyl)propane-2-one giving unsymmetric ketones.

  16. 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.

  17. Effects of fatty acids and ketone bodies on basal insulin secretion in type 2 diabetes.

    PubMed

    Boden, G; Chen, X

    1999-03-01

    The objective of this study was to assess the role of free fatty acids (FFAs) as insulin secretagogues in patients with type 2 diabetes. To this end, basal insulin secretion rates (ISR) in response to acute increases in plasma FFAs were evaluated in patients with type 2 diabetes and in age- and weight-matched nondiabetic control subjects during 1) intravenous infusion of lipid plus heparin (L/H), which stimulated intravascular lipolysis, and 2) the FFA rebound, which followed lowering of plasma FFAs with nicotinic acid (NA) and was a consequence of increased lipolysis from the subject's own adipose tissue. At comparable euglycemia, diabetic patients had similar ISR but higher plasma beta-hydroxybutyrate (beta-OHB) levels during L/H infusion and higher plasma FFA and beta-OHB levels during the FFA rebound than nondiabetic control subjects. Correlating ISR with plasma FFA plus beta-OHB levels showed that in response to the same changes in FFA plus beta-OHB levels, diabetic patients secreted approximately 30% less insulin than nondiabetic control subjects. In addition, twice as much insulin was secreted during L/H infusion as during the FFA rebound in response to the same FFA/beta-OHB stimulation by both diabetic patients and control subjects. Glycerol, which was present in the infused lipid (272 mmol/l) did not affect ISR. We concluded that 1) assessment of FFA effects on ISR requires consideration of effects on ISR by ketone bodies; 2) ISR responses to FFA/beta-OHB were defective in patients with type 2 diabetes (partial beta-cell lipid blindness), but this defect was compensated by elevated plasma levels of FFAs and ketone bodies; and 3) approximately two times more insulin was released per unit change in plasma FFA plus beta-OHB during L/H infusion than during the FFA rebound after NA. The reason for this remains to be explored.

  18. Comparison of Properties among Dendritic and Hyperbranched Poly(ether ether ketone)s and Linear Poly(ether ketone)s.

    PubMed

    Morikawa, Atsushi

    2016-02-16

    Poly(ether ether ketone) dendrimers and hyperbranched polymers were prepared from 3,5-dimethoxy-4'-(4-fluorobenzoyl)diphenyl ether and 3,5-dihydroxy-4'-(4-fluorobenzoyl)diphenyl ether through aromatic nucleophilic substitution reactions. 1-(tert-Butyldimethylsiloxy)-3,5-bis(4-fluorobenzoyl)benzene was polycondensed with bisphenols, followed by cleavage of the protective group to form linear poly(ether ketone)s having the same hydroxyl groups in the side chains as the chain ends of the dendrimer and hyperbranched polymers. Their properties, such as solubilities, reduced viscosities, and thermal properties, were compared with one another. Similar comparisons were also carried out among the corresponding methoxy group polymers, and the size of the molecules was shown to affect the properties.

  19. Ketone ester effects on metabolism and transcription.

    PubMed

    Veech, Richard L

    2014-10-01

    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.

  20. 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

  1. [Changes of the storage stability of ketones collected on activated coconut carbon in environmental ketone measurement].

    PubMed

    Sakamroto, Takayuki; Hinoue, Mitsuo; Yoshikawa, Masahiro

    2011-06-01

    The storage stability for six ketones was studied on four activated coconut carbons commonly used for air sampling in Japan. As the ratios of the enol form of cyclohexanone and methyl ethyl ketone are high, the ketones showed drastic losses during storage (storage stability), which could be attributed to catalytic oxidation and chemisorption. Moreover, adsorbed water caused a further decrease in recoveries of the ketones from the carbons. Because keto-enol tautomerism and hydration are catalyzed by acid or base, the relationships between the recoveries of the ketones from the carbons and pH in the aqueous solution of the carbons and the ignition residue of the carbons were investigated. As a result, the intensity of acidity or basicity of the carbons correlated with the loss of the ketones during storage, but the ignition residue of the carbons did not. Therefore, these results lead us to the conclusion that a more neutral coconut carbon is more suitable for the collection of aliphatic ketones, and activated coconut carbons are not suitable for cyclohexanone.

  2. 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.

  3. Highly Concentrated Catalytic Asymmetric Allylation of Ketones

    PubMed Central

    Wooten, Alfred J.; Kim, Jeung Gon; Walsh, Patrick J.

    2008-01-01

    We report the catalytic asymmetric allylation of ketones under highly concentrated reaction conditions with a catalyst generated from titanium tetraisopropoxide and BINOL (1:2 ratio) in the presence of isopropanol. This catalyst promotes the addition of tetraallylstannane to a variety of ketones to produce tertiary homoallylic alcohols in excellent yield (80–99%) with high enantioselectivities (79–95%). The resulting homoallylic alcohols can also be epoxidized in situ using tert-butyl hydroperoxide (TBHP) to afford cyclic epoxy alcohols in high yield (84–87%). PMID:17249767

  4. Highly concentrated catalytic asymmetric allylation of ketones.

    PubMed

    Wooten, Alfred J; Kim, Jeung Gon; Walsh, Patrick J

    2007-02-01

    [reaction: see text] We report the catalytic asymmetric allylation of ketones under highly concentrated reaction conditions with a catalyst generated from titanium tetraisopropoxide and BINOL (1:2 ratio) in the presence of isopropanol. This catalyst promotes the addition of tetraallylstannane to a variety of ketones to produce tertiary homoallylic alcohols in excellent yield (80-99%) with high enantioselectivities (79-95%). The resulting homoallylic alcohols can also be epoxidized in situ using tert-butyl hydroperoxide (TBHP) to afford cyclic epoxy alcohols in high yield (84-87%).

  5. 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.

  6. 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.

  7. 40 CFR 721.4568 - Methylpolychloro aliphatic ketone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Methylpolychloro aliphatic ketone. 721... Substances § 721.4568 Methylpolychloro aliphatic ketone. (a) Chemical substance and significant new uses... ketone (PMN No. P-91-1321) is subject to reporting under this section for the significant new uses...

  8. 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.

  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... 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 reporting...

  10. 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 reporting...

  11. 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 reporting...

  12. 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 reporting...

  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 reporting...

  14. Thiourea-Catalyzed Enantioselective Cyanosilylation of Ketones

    PubMed Central

    Fuerst, Douglas E.; Jacobsen, Eric N.

    2011-01-01

    The new chiral amino thiourea catalyst 3d promotes the highly enantioselective cyanosilylation of a wide variety of ketones. The hindered tertiary amine substituent plays a crucial role both with regard to stereoinduction and reactivity, suggesting a cooperative mechanism involving electrophile activation by thiourea and nucleophile activation by the amine. PMID:15969569

  15. Stereoselective Borylative Ketone-Diene Coupling

    PubMed Central

    Cho, Hee Yeon; Yu, Zhiyong; Morken, James P.

    2011-01-01

    In the presence of catalytic Ni(cod)2 and P(t-Bu)3, ketones, dienes, and B2(pin)2 undergo a stereoselective multicomponent coupling reaction. Upon oxidation, the reaction furnishes 1,3-diols as the major reaction product. PMID:21905748

  16. Stereoselective borylative ketone-diene coupling.

    PubMed

    Cho, Hee Yeon; Yu, Zhiyong; Morken, James P

    2011-10-07

    In the presence of catalytic Ni(cod)(2) and P(t-Bu)(3), ketones, dienes, and B(2)(pin)(2) undergo a stereoselective multicomponent coupling reaction. Upon oxidation, the reaction furnishes 1,3-diols as the major reaction product. © 2011 American Chemical Society

  17. nBu4NI-catalyzed oxidative imidation of ketones with imides: synthesis of α-amino ketones.

    PubMed

    Lv, Yunhe; Li, Yan; Xiong, Tao; Lu, Yu; Liu, Qun; Zhang, Qian

    2014-03-04

    nBu4NI-Catalyzed oxidative imidation of ketones and imides for the synthesis of α-amino ketones were realized for the first time. The methodology is characterized by its wide substrate scope even for acetone with readily available phthalimide, saccharin and succinimide, which opens a new pathway for direct imidation of ketones.

  18. Thermochemistry and bond dissociation energies of ketones.

    PubMed

    Hudzik, Jason M; Bozzelli, Joseph W

    2012-06-14

    Ketones are a major class of organic chemicals and solvents, which contribute to hydrocarbon sources in the atmosphere, and are important intermediates in the oxidation and combustion of hydrocarbons and biofuels. Their stability, thermochemical properties, and chemical kinetics are important to understanding their reaction paths and their role as intermediates in combustion processes and in atmospheric chemistry. In this study, enthalpies (ΔH°(f 298)), entropies (S°(T)), heat capacities (C(p)°(T)), and internal rotor potentials are reported for 2-butanone, 3-pentanone, 2-pentanone, 3-methyl-2-butanone, and 2-methyl-3-pentanone, and their radicals corresponding to loss of hydrogen atoms. A detailed evaluation of the carbon-hydrogen bond dissociation energies (C-H BDEs) is also performed for the parent ketones for the first time. Standard enthalpies of formation and bond energies are calculated at the B3LYP/6-31G(d,p), B3LYP/6-311G(2d,2p), CBS-QB3, and G3MP2B3 levels of theory using isodesmic reactions to minimize calculation errors. Structures, moments of inertia, vibrational frequencies, and internal rotor potentials are calculated at the B3LYP/6-31G(d,p) density functional level and are used to determine the entropies and heat capacities. The recommended ideal gas-phase ΔH°(f 298), from the average of the CBS-QB3 and G3MP2B3 levels of theory, as well as the calculated values for entropy and heat capacity are shown to compare well with the available experimental data for the parent ketones. Bond energies for primary, secondary, and tertiary radicals are determined; here, we find the C-H BDEs on carbons in the α position to the ketone group decrease significantly with increasing substitution on these α carbons. Group additivity and hydrogen-bond increment values for these ketone radicals are also determined.

  19. Fe/Cu-Mediated One-Pot Ketone Synthesis.

    PubMed

    Kumar, Vemula Praveen; Babu, Vaddela Sudheer; Yahata, Kenzo; Kishi, Yoshito

    2017-05-19

    An Fe/Cu-mediated one-pot ketone synthesis was reported. Unlike Ni- and Pd-mediated one-pot ketone syntheses, the reported Fe/Cu-mediated method allowed selective activation and coupling of alkyl iodides over vinyl iodides. The newly developed one-pot ketone synthesis was applied to a synthesis of vinyl iodide/ketone 13, the left half of halichondrin B, as well as vinyl iodide/ketone 8a, the C20-C26 building block of halichondrins.

  20. Biomarkers, ketone bodies, and the prevention of Alzheimer's disease.

    PubMed

    VanItallie, Theodore B

    2015-03-01

    Sporadic Alzheimer's disease (spAD) has three successive phases: preclinical, mild cognitive impairment, and dementia. Individuals in the preclinical phase are cognitively normal. Diagnosis of preclinical spAD requires evidence of pathologic brain changes provided by established biomarkers. Histopathologic features of spAD include (i) extra-cellular cerebral amyloid plaques and intracellular neurofibrillary tangles that embody hyperphosphorylated tau; and (ii) neuronal and synaptic loss. Amyloid-PET brain scans conducted during spAD's preclinical phase have disclosed abnormal accumulations of amyloid-beta (Aβ) in cognitively normal, high-risk individuals. However, this measure correlates poorly with changes in cognitive status. In contrast, MRI measures of brain atrophy consistently parallel cognitive deterioration. By the time dementia appears, amyloid deposition has already slowed or ceased. When a new treatment offers promise of arresting or delaying progression of preclinical spAD, its effectiveness must be inferred from intervention-correlated changes in biomarkers. Herein, differing tenets of the amyloid cascade hypothesis (ACH) and the mitochondrial cascade hypothesis (MCH) are compared. Adoption of the ACH suggests therapeutic research continue to focus on aspects of the amyloid pathways. Adoption of the MCH suggests research emphasis be placed on restoration and stabilization of mitochondrial function. Ketone ester (KE)-induced elevation of plasma ketone body (KB) levels improves mitochondrial metabolism and prevents or delays progression of AD-like pathologic changes in several AD animal models. Thus, as a first step, it is imperative to determine whether KE-caused hyperketonemia can bring about favorable changes in biomarkers of AD pathology in individuals who are in an early stage of AD's preclinical phase.

  1. Exogenous Ketone Supplements Reduce Anxiety-Related Behavior in Sprague-Dawley and Wistar Albino Glaxo/Rijswijk Rats

    PubMed Central

    Ari, Csilla; Kovács, Zsolt; Juhasz, Gabor; Murdun, Cem; Goldhagen, Craig R.; Koutnik, Andrew P.; Poff, Angela M.; Kesl, Shannon L.; D’Agostino, Dominic P.

    2016-01-01

    Nutritional ketosis has been proven effective for seizure disorders and other neurological disorders. The focus of this study was to determine the effects of ketone supplementation on anxiety-related behavior in Sprague-Dawley (SPD) and Wistar Albino Glaxo/Rijswijk (WAG/Rij) rats. We tested exogenous ketone supplements added to food and fed chronically for 83 days in SPD rats and administered sub-chronically for 7 days in both rat models by daily intragastric gavage bolus followed by assessment of anxiety measures on elevated plus maze (EPM). The groups included standard diet (SD) or SD + ketone supplementation. Low-dose ketone ester (LKE; 1,3-butanediol-acetoacetate diester, ~10 g/kg/day, LKE), high dose ketone ester (HKE; ~25 g/kg/day, HKE), beta-hydroxybutyrate-mineral salt (βHB-S; ~25 g/kg/day, KS) and βHB-S + medium chain triglyceride (MCT; ~25 g/kg/day, KSMCT) were used as ketone supplementation for chronic administration. To extend our results, exogenous ketone supplements were also tested sub-chronically on SPD rats (KE, KS and KSMCT; 5 g/kg/day) and on WAG/Rij rats (KE, KS and KSMCT; 2.5 g/kg/day). At the end of treatments behavioral data collection was conducted manually by a blinded observer and with a video-tracking system, after which blood βHB and glucose levels were measured. Ketone supplementation reduced anxiety on EPM as measured by less entries to closed arms (sub-chronic KE and KS: SPD rats and KSMCT: WAG/Rij rats), more time spent in open arms (sub-chronic KE: SPD and KSMCT: WAG/Rij rats; chronic KSMCT: SPD rats), more distance traveled in open arms (chronic KS and KSMCT: SPD rats) and by delayed latency to entrance to closed arms (chronic KSMCT: SPD rats), when compared to control. Our data indicates that chronic and sub-chronic ketone supplementation not only elevated blood βHB levels in both animal models, but reduced anxiety-related behavior. We conclude that ketone supplementation may represent a promising anxiolytic strategy through a

  2. Exogenous Ketone Supplements Reduce Anxiety-Related Behavior in Sprague-Dawley and Wistar Albino Glaxo/Rijswijk Rats.

    PubMed

    Ari, Csilla; Kovács, Zsolt; Juhasz, Gabor; Murdun, Cem; Goldhagen, Craig R; Koutnik, Andrew P; Poff, Angela M; Kesl, Shannon L; D'Agostino, Dominic P

    2016-01-01

    Nutritional ketosis has been proven effective for seizure disorders and other neurological disorders. The focus of this study was to determine the effects of ketone supplementation on anxiety-related behavior in Sprague-Dawley (SPD) and Wistar Albino Glaxo/Rijswijk (WAG/Rij) rats. We tested exogenous ketone supplements added to food and fed chronically for 83 days in SPD rats and administered sub-chronically for 7 days in both rat models by daily intragastric gavage bolus followed by assessment of anxiety measures on elevated plus maze (EPM). The groups included standard diet (SD) or SD + ketone supplementation. Low-dose ketone ester (LKE; 1,3-butanediol-acetoacetate diester, ~10 g/kg/day, LKE), high dose ketone ester (HKE; ~25 g/kg/day, HKE), beta-hydroxybutyrate-mineral salt (βHB-S; ~25 g/kg/day, KS) and βHB-S + medium chain triglyceride (MCT; ~25 g/kg/day, KSMCT) were used as ketone supplementation for chronic administration. To extend our results, exogenous ketone supplements were also tested sub-chronically on SPD rats (KE, KS and KSMCT; 5 g/kg/day) and on WAG/Rij rats (KE, KS and KSMCT; 2.5 g/kg/day). At the end of treatments behavioral data collection was conducted manually by a blinded observer and with a video-tracking system, after which blood βHB and glucose levels were measured. Ketone supplementation reduced anxiety on EPM as measured by less entries to closed arms (sub-chronic KE and KS: SPD rats and KSMCT: WAG/Rij rats), more time spent in open arms (sub-chronic KE: SPD and KSMCT: WAG/Rij rats; chronic KSMCT: SPD rats), more distance traveled in open arms (chronic KS and KSMCT: SPD rats) and by delayed latency to entrance to closed arms (chronic KSMCT: SPD rats), when compared to control. Our data indicates that chronic and sub-chronic ketone supplementation not only elevated blood βHB levels in both animal models, but reduced anxiety-related behavior. We conclude that ketone supplementation may represent a promising anxiolytic strategy through a

  3. 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.

  4. Application of metabonomic strategy to discover an unreported active ingredient in LiuWeiDiHuang pills suppressing beta-glucuronidase.

    PubMed

    Xie, Baogang; Zhang, Zhirong; Gong, Tao; Zhang, Ningning; Wang, Huiyun; Zou, Huiqing

    2015-01-01

    Identification of the bioactive ingredient from traditional Chinese medicine (TCM) remains a challenging task by traditional approach that focuses on chemical isolation coupled with biological activity screening. Here, we present a metabonomics-based approach for bioactive ingredient discovery in LiuWeiDiHuang pills (LWPs). First, a non-targeted high-performance liquid chromatography ultraviolet (HPLC-UV) profiling of rat urine was used to discriminate urinary profiling intervened by LWPs. Orthogonal partial least-squares discriminant analysis (OPLS-DA) revealed that eight chromatographic peaks made a significant contribution to the classification of the LWPs group and the control group. Five of these chromatographic peaks were successfully isolated and identified as hippurate, genistein (GT), daidzein (DZ), and glucuronide conjugate of GT and that of DZ by mass spectroscopy (MS). Subsequently, we found that LWPs significantly decreased the activity of intestinal β-glucuronidase by 18 % and exerted a dose-dependent inhibitory effect on rat liver lysosomal fraction, suggesting that LWPs were a β-glucuronidase inhibitor. In the end, by inhibiting β-glucuronidase-guided isolation, D-glucaro-1,4-lactone, a previously unreported ingredient of LWPs, was identified by MS, MS/MS, and nuclear magnetic resonance spectroscopy. Our findings indicated that metabonomics might increase research productivity toward the drug targets and/or bioactive compounds from TCM.

  5. Role of glucose and ketone bodies in the metabolic control of experimental brain cancer.

    PubMed

    Seyfried, T N; Sanderson, T M; El-Abbadi, M M; McGowan, R; Mukherjee, P

    2003-10-06

    Brain tumours lack metabolic versatility and are dependent largely on glucose for energy. This contrasts with normal brain tissue that can derive energy from both glucose and ketone bodies. We examined for the first time the potential efficacy of dietary therapies that reduce plasma glucose and elevate ketone bodies in the CT-2A syngeneic malignant mouse astrocytoma. C57BL/6J mice were fed either a standard diet unrestricted (SD-UR), a ketogenic diet unrestricted (KD-UR), the SD restricted to 40% (SD-R), or the KD restricted to 40% of the control standard diet (KD-R). Body weights, tumour weights, plasma glucose, beta-hydroxybutyrate (beta-OHB), and insulin-like growth factor 1 (IGF-1) were measured 13 days after tumour implantation. CT-2A growth was rapid in both the SD-UR and KD-UR groups, but was significantly reduced in both the SD-R and KD-R groups by about 80%. The results indicate that plasma glucose predicts CT-2A growth and that growth is dependent more on the amount than on the origin of dietary calories. Also, restriction of either diet significantly reduced the plasma levels of IGF-1, a biomarker for angiogenesis and tumour progression. Owing to a dependence on plasma glucose, IGF-1 was also predictive of CT-2A growth. Ketone bodies are proposed to reduce stromal inflammatory activities, while providing normal brain cells with a nonglycolytic high-energy substrate. Our results in a mouse astrocytoma suggest that malignant brain tumours are potentially manageable with dietary therapies that reduce glucose and elevate ketone bodies.

  6. Administration of Poly[di(sodium carboxylatoethylphenoxy)phosphazene] (PCEP) and Avian Beta Defensin as Adjuvants in Inactivated Inclusion Body Hepatitis Virus and its Hexon Protein-Based Experimental Vaccine Formulations in Chickens.

    PubMed

    Dar, Arshud; Tipu, Masroor; Townsend, Hugh; Potter, Andy; Gerdts, Volker; Tikoo, Suresh

    2015-12-01

    Inclusion body hepatitis (IBH) is one of the major infectious diseases adversely affecting the poultry industry of the United States and Canada. Currently, no effective and safe vaccine is available for the control of IBH virus (IBHV) infection in chickens. However, based on the excellent safety and immunogenic profiles of experimental veterinary vaccines developed with the use of new generation adjuvants, we hypothesized that characterization of vaccine formulations containing inactivated IBHV or its capsid protein hexon as antigens, along with poly[di(sodium carboxylatoethylphenoxy)phosphazene] (PCEP) and avian beta defensin 2 (ABD2) as vaccine adjuvants, will be helpful in development of an effective and safe vaccine formulation for IBH. Our data demonstrated that experimental administration of vaccine formulations containing inactivated IBHV and a mixture of PCEP with or without ABD2 as an adjuvant induced significantly higher antibody responses compared with other vaccine formulations, while hexon protein-based vaccine formulations showed relatively lower levels of antibody responses. Thus, a vaccine formulation containing inactivated IBHV with PCEP or a mixture of PCEP and ABD2 (with a reduced dosage of PCEP) as an adjuvant may serve as a potential vaccine candidate. However, in order to overcome the risks associated with whole virus inactivated vaccines, characterization of additional viral capsid proteins, including fiber protein and penton of IBHV along with hexon protein in combination with more new generation adjuvants, will be helpful in further improvements of vaccines against IBHV infection.

  7. Mass and Ion Transport in Ketones and Ketone Electrolytes: Comparison with Acetate Systems.

    PubMed

    Bopege, Dharshani N; Petrowsky, Matt; Johnson, Matthew B; Frech, Roger

    2013-03-01

    Self-diffusion coefficient measurements were performed for pure n-alkyl ketone liquids using the pulsed field gradient NMR spin-echo technique. Ionic conductivities and dielectric constants of 0.0055 mol·L(-1) tetrabutylammonium trifluoromethanesulfonate in 2-pentanone, 2-hexanone, 2-heptanone, 2-octanone, 2-nonanone, and 2-decanone were also measured. The temperature-dependent conductivities and diffusion coefficients over the range 5-80 °C can be described using the compensated Arrhenius formalism. Compensated Arrhenius equation plots were used to calculate the average activation energy for both sets of data. The average activation energy from conductivity data is approximately equal to that from diffusion data. The data for the pure ketones and ketone-based electrolytes are compared with analogous data for pure n-alkyl acetates and n-alkyl acetate-based electrolytes.

  8. Ketone bodies and islet function: sup 45 Ca handling, insulin synthesis, and release

    SciTech Connect

    Malaisse, W.J.; Lebrun, P.; Yaylali, B.; Camara, J.; Valverde, I.; Sener, A. )

    1990-07-01

    D-(-)-beta-Hydroxybutyrate and acetoacetate cause a rapid, sustained, and rapidly reversible stimulation of insulin release from rat pancreatic islets incubated in the presence, but not absence, of D-glucose. This coincides with stimulation of both proinsulin biosynthesis and {sup 45}Ca net uptake. The ketone bodies also decrease {sup 45}Ca outflow from prelabeled islets perifused in the absence of Ca{sup 2+} and, in contrast, enhance effluent radioactivity in the presence of Ca{sup 2+}. In the presence of D-glucose, the secretory response to D-(-)-beta-hydroxybutyrate is concentration related in the 2.5-20 mM range, abolished in the absence of Ca{sup 2+} or presence of KCN, and enhanced by theophylline and forskolin. It corresponds grossly to a shift to the left of the sigmoidal curve relating insulin output to the ambient concentration of D-glucose. The secretory, biosynthetic, and cationic response to acetoacetate is less marked than that evoked by an equimolar concentration of D-(-)-beta-hydroxybutyrate. These features are compatible with the view that the insulinotropic action of ketone bodies would be causally linked to their metabolism in islet cells.

  9. A bio-catalytic approach to aliphatic ketones.

    PubMed

    Xiong, Mingyong; Deng, Jin; Woodruff, Adam P; Zhu, Minshan; Zhou, Jun; Park, Sun Wook; Li, Hui; Fu, Yao; Zhang, Kechun

    2012-01-01

    Depleting oil reserves and growing environmental concerns have necessitated the development of sustainable processes to fuels and chemicals. Here we have developed a general metabolic platform in E. coli to biosynthesize carboxylic acids. By engineering selectivity of 2-ketoacid decarboxylases and screening for promiscuous aldehyde dehydrogenases, synthetic pathways were constructed to produce both C5 and C6 acids. In particular, the production of isovaleric acid reached 32 g/L (0.22 g/g glucose yield), which is 58% of the theoretical yield. Furthermore, we have developed solid base catalysts to efficiently ketonize the bio-derived carboxylic acids such as isovaleric acid and isocaproic acid into high volume industrial ketones: methyl isobutyl ketone (MIBK, yield 84%), diisobutyl ketone (DIBK, yield 66%) and methyl isoamyl ketone (MIAK, yield 81%). This hybrid "Bio-Catalytic conversion" approach provides a general strategy to manufacture aliphatic ketones, and represents an alternate route to expanding the repertoire of renewable chemicals.

  10. A Bio-Catalytic Approach to Aliphatic Ketones

    PubMed Central

    Xiong, Mingyong; Deng, Jin; Woodruff, Adam P.; Zhu, Minshan; Zhou, Jun; Park, Sun Wook; Li, Hui; Fu, Yao; Zhang, Kechun

    2012-01-01

    Depleting oil reserves and growing environmental concerns have necessitated the development of sustainable processes to fuels and chemicals. Here we have developed a general metabolic platform in E. coli to biosynthesize carboxylic acids. By engineering selectivity of 2-ketoacid decarboxylases and screening for promiscuous aldehyde dehydrogenases, synthetic pathways were constructed to produce both C5 and C6 acids. In particular, the production of isovaleric acid reached 32 g/L (0.22 g/g glucose yield), which is 58% of the theoretical yield. Furthermore, we have developed solid base catalysts to efficiently ketonize the bio-derived carboxylic acids such as isovaleric acid and isocaproic acid into high volume industrial ketones: methyl isobutyl ketone (MIBK, yield 84%), diisobutyl ketone (DIBK, yield 66%) and methyl isoamyl ketone (MIAK, yield 81%). This hybrid “Bio-Catalytic conversion” approach provides a general strategy to manufacture aliphatic ketones, and represents an alternate route to expanding the repertoire of renewable chemicals. PMID:22416247

  11. Poly (Aryl Ether Ketones) Bearing Alkylated Side Chains

    NASA Technical Reports Server (NTRS)

    Cassidy, Patrick E. (Inventor); Fitch, John W., III (Inventor); Gronewald, Scott D. (Inventor); St.Clair, Ann K. (Inventor); Stoakley, Diane M. (Inventor)

    2002-01-01

    This invention relates generally to poly(aryl ether ketones) bearing alkylated side chains. It relates particularly to soluble, thermally stable. low dielectric poly(aryl ether ketones) with alkylated side chains and especially to films and coatings thereof. These poly(aryl ether ketones) have a structural formula wherein Y is selected from the group consisting of CF3 and CH3; and wherein R is C(sub n)H(sub (2n+1)) and n = 11-18.

  12. Application of aryloximes as solid-phase ketone linkers.

    PubMed

    Lepore, Salvatore D; Wiley, Michael R

    2003-01-09

    In both solution and the solid phase, a variety of ketone oxime anions have been treated with 4-substituted-2-fluorobenzonitriles to give the corresponding nucleophilic aromatic substitution aryloxime adducts. Under aqueous acidic conditions, these adducts underwent cyclization to give the corresponding ketones. Suzuki and amide coupling reactions were also successfully performed on two resin-bound oximes followed by subsequent cyclorelease to give ketone product in good yields and purities. [reaction--see text

  13. 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.

  14. Fluorinated Poly(Phenylene Ether Ketones)

    NASA Technical Reports Server (NTRS)

    St. Clair, Anne K.; Cassidy, Patrick E.; Tullos, Gordon L.

    1994-01-01

    Fluorinated poly(phenylene ether ketones) are colorless, transparent, low-dielectric-constant, highly thermally stable polymers. Particularly suitable for use as film and coating materials in electronic and thermal-control applications such as; passivant insulating coats and interlevel dielectrics in microelectronic circuits, or as protective transparent coats on solar cells or mirrors. Solubility and transparency of 12F-PEK along with its lower dielectric constant and other properties make it more useful as dielectric film and coating material in many applications.

  15. IRIS Toxicological Review of Methyl Ethyl Ketone (2003 Final)

    EPA Science Inventory

    EPA announced 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 toxicological review have been added to the IRIS Database....

  16. Ketones prevent synaptic dysfunction induced by mitochondrial respiratory complex inhibitors

    PubMed Central

    Kim, Do Young; Vallejo, Johana; Rho, Jong M

    2010-01-01

    Abstract Ketones have previously shown beneficial effects in models of neurodegenerative disorders, particularly against associated mitochondrial dysfunction and cognitive impairment. However, evidence of a synaptic protective effect of ketones remains lacking. We tested the effects of ketones on synaptic impairment induced by mitochondrial respiratory complex (MRC) inhibitors using electrophysiological, reactive oxygen species (ROS) imaging and biochemical techniques. MRC inhibitors dose-dependently suppressed both population spike (PS) and field potential amplitudes in the CA1 hippocampus. Pre-treatment with ketones strongly prevented changes in the PS, whereas partial protection was seen in the field potential. Rotenone (Rot; 100 nmol/L), a MRC I inhibitor, suppressed synaptic function without altering ROS levels and PS depression by Rot was unaffected by antioxidants. In contrast, antioxidant-induced PS recovery against the MRC II inhibitor 3-nitropropionic acid (3-NP; 1 mmol/L) was similar to the synaptic protective effects of ketones. Ketones also suppressed ROS generation induced by 3-NP. Finally, ketones reversed the decreases in ATP levels caused by Rot and 3-NP. In summary, our data demonstrate that ketones can preserve synaptic function in CA1 hippocampus induced by MRC dysfunction, likely through an antioxidant action and enhanced ATP generation. PMID:20374433

  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....117 Methyl isobutyl ketone. (a) Acidity (as acetic acid). 0.02 percent by weight, maximum. (b) Color...

  18. 27 CFR 21.117 - Methyl isobutyl ketone.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Methyl isobutyl ketone. 21.117 Section 21.117 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU....117 Methyl isobutyl ketone. (a) Acidity (as acetic acid). 0.02 percent by weight, maximum. (b) Color...

  19. Tandem Reaction of Enynyl Acetate: Precursor of Allenyl Ketones.

    PubMed

    Okamoto, Noriko; Sueda, Takuya; Yanada, Reiko

    2016-01-01

    Deacetylation of enynyl acetates under basic conditions allows convenient access to reactive allenyl ketones, which can then undergo 1,4-addition of nucleophiles to furnish β,γ-unsaturated ketones. Benzofuran and indole derivatives have also been obtained from enynyl acetates with an o-hetero-atom-substituted aryl group via intramolecular 1,4-addition.

  20. 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....117 Methyl isobutyl ketone. (a) Acidity (as acetic acid). 0.02 percent by weight, maximum. (b) Color...

  1. 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....117 Methyl isobutyl ketone. (a) Acidity (as acetic acid). 0.02 percent by weight, maximum. (b) Color...

  2. 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.

  3. One-Step Conversion of Methyl Ketones to Acyl Chlorides.

    PubMed

    Zaragoza, Florencio

    2015-10-16

    Treatment of aromatic and heteroaromatic methyl ketones with sulfur monochloride and catalytic amounts of pyridine in refluxing chlorobenzene leads to the formation of acyl chlorides. Both electron-rich and electron-poor aryl methyl ketones can be used as starting materials. The resulting C1-byproduct depends on the precise reaction conditions chosen.

  4. Deaminative and decarboxylative catalytic alkylation of amino acids with ketones.

    PubMed

    Kalutharage, Nishantha; Yi, Chae S

    2013-12-16

    It cuts two ways: The cationic [Ru-H] complex catalyzes selective coupling of α- and β-amino acids with ketones to form α-alkylated ketone products. The reaction involves CC and CN bond cleavage which result in regio- and stereoselective alkylation using amino acids. A broad substrate scope and high functional-group tolerance is demonstrated.

  5. IRIS Toxicological Review of Methyl Ethyl Ketone (2003 Final)

    EPA Science Inventory

    EPA announced 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 toxicological review have been added to the IRIS Database....

  6. 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.

  7. 27 CFR 21.118 - Methyl n-butyl ketone.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Methyl n-butyl ketone. 21.118 Section 21.118 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU....118 Methyl n-butyl ketone. (a) Acidity (as acetic acid). 0.02 percent by weight, maximum. (b)...

  8. 21 CFR 862.1435 - Ketones (nonquantitative) test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...) test system is a device intended to identify ketones in urine and other body fluids. Identification of... 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...

  9. 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... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Ketones (nonquantitative) test system. 862.1435 Section 862.1435 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN...

  10. 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... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Ketones (nonquantitative) test system. 862.1435 Section 862.1435 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN...

  11. 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... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Ketones (nonquantitative) test system. 862.1435 Section 862.1435 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN...

  12. 27 CFR 21.118 - Methyl n-butyl 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 n-butyl ketone. 21.118 Section 21.118 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU....118 Methyl n-butyl ketone. (a) Acidity (as acetic acid). 0.02 percent by weight, maximum. (b) Color...

  13. Facile Rearrangement of 3-Oxoalkyl Radicals is Evident in Low-Temperature Gas-Phase Oxidation of Ketones

    SciTech Connect

    Scheer, Adam M.; Welz, Oliver; Sasaki, Darryl Y.; Osborn, David L.; Taatjes, Craig A.

    2013-08-23

    The pulsed photolytic chlorine-initiated oxidation of methyl-tert-butyl ketone (MTbuK), di-tert-butyl ketone (DTbuK), and a series of partially deuterated diethyl ketones (DEK) is studied in the gas phase at 8 Torr and 550–650 K. Products are monitored as a function of reaction time, mass, and photoionization energy using multiplexed photoionization mass spectrometry with tunable synchrotron ionizing radiation. The results establish that the primary 3-oxoalkyl radicals of those ketones, formed by abstraction of a hydrogen atom from the carbon atom in γ-position relative to the carbonyl oxygen, undergo a rapid rearrangement resulting in an effective 1,2-acyl group migration, similar to that in a Dowd–Beckwith ring expansion. Without this rearrangement, peroxy radicals derived from MTbuK and DTbuK cannot undergo HO2 elimination to yield a closed-shell unsaturated hydrocarbon coproduct. However, not only are these coproducts observed, but they represent the dominant oxidation channels of these ketones under the conditions of this study. For MTbuK and DTbuK, the rearrangement yields a more stable tertiary radical, which provides the thermodynamic driving force for this reaction. Even in the absence of such a driving force in the oxidation of partially deuterated DEK, the 1,2-acyl group migration is observed. Quantum chemical (CBS-QB3) calculations show the barrier for gas-phase rearrangement to be on the order of 10 kcal mol–1. The MTbuK oxidation experiments also show several minor channels, including β-scission of the initial radicals and cyclic ether formation.

  14. A facile and effective synthesis of alpha-(1-->6)-linked mannose di-, tri-, tetra-, hexa-, octa-, and dodecasaccharides, and beta-(1-->6)-linked glucose di-, tri-, tetra-, hexa-, and octasaccharides using sugar trichloroacetimidates as the donors and unprotected or partially protected glycosides as the acceptors.

    PubMed

    Zhu, Y; Kong, F

    2001-05-08

    Reaction of 2,3,4,6-tetra-O-acetyl-alpha-D-mannopyranosyl trichloroimidate with allyl alpha-D-mannopyranoside in the presence of TMSOTf selectively gave allyl 2,3,4,6-tetra-O-acetyl-alpha-D-mannopyranosyl-(1-->6)-alpha-D-mannopyranoside through an orthoester intermediate. Benzoylation of 3, followed by deallylation, and then trichloroimidation afforded the disaccharide donor 2,3,4,6-tetra-O-acetyl-alpha-D-mannopyranosyl-(1-->6)-2,3,4-tri-O-benzoyl-alpha-D-mannopyranosyl trichloroimidate, while benzoylation of 3 followed by selective removal of acetyl groups yielded the disaccharide acceptor allyl alpha-D-mannopyranosyl-(1-->6)-2,3,4-tri-O-benzoyl-alpha-D-mannopyranoside. Coupling of 5 with 6 gave the tetrasaccharide allyl 2,3,4,6-tetra-O-acetyl-alpha-D-mannopyranosyl-(1-->6)-2,3,4-tri-O-benzoyl-alpha-D-mannopyranosyl-(1-->6)-alpha-D-mannopyranosyl-(1-->6)-2,3,4-tri-O-benzoyl-alpha-D-mannopyranoside, which were converted into the tetrasaccharide donor 2,3,4,6-tetra-O-acetyl-alpha-D-mannopyranosyl-(1-->6)-2,3,4-tri-O-benzoyl-alpha-D-mannopyranosyl-(1-->6)-2,3,4-tri-O-benzoyl-alpha-D-mannopyranosyl-(1-->6)-2,3,4-tri-O-benzoyl-alpha-D-mannopyranosyl trichloroimdate and the tetrasaccharide acceptor allyl alpha-D-mannopyranosyl-(1-->6)-2,3,4-tri-O-benzoyl-alpha-D-mannopyranosyl-(1-->6)-2,3,4-tri-O-benzoyl-alpha-D-mannopyranosyl-(1-->6)-2,3,4-tri-O-benzoyl-alpha-D-mannopyranoside, respectively, by the same strategies as used for conversion of 3 into 5 and 6. Condensation of 5 with 13 gave the hexasaccharide 14, while condensation of 12 with 13 gave the octasaccharide 17. Dodecasaccharide 21 was obtained by the coupling of 12 with the octasaccharide acceptor 20. Similar strategies were used for the syntheses of beta-(1-->6)-linked glucose di-, tri-, tetra-, hexa-, and octamers. Deprotection of the oligosaccharides in ammonia-saturated methanol yielded the free alpha-(1-->6)-linked mannosyl and beta-(1-->6)-linked glucosyl oligomers.

  15. Biocatalytic strategies for the asymmetric synthesis of alpha-hydroxy ketones.

    PubMed

    Hoyos, Pilar; Sinisterra, Josep-Vicent; Molinari, Francesco; Alcántara, Andrés R; Domínguez de María, Pablo

    2010-02-16

    The development of efficient syntheses for enantiomerically enriched alpha-hydroxy ketones is an important research focus in the pharmaceutical industry. For example, alpha-hydroxy ketones are found in antidepressants, in selective inhibitors of amyloid-beta protein production (used in the treatment of Alzheimer's), in farnesyl transferase inhibitors (Kurasoin A and B), and in antitumor antibiotics (Olivomycin A and Chromomycin A3). Moreover, alpha-hydroxy ketones are of particular value as fine chemicals because of their utility as building blocks for the production of larger molecules. They can also be used in preparing many other important structures, such as amino alcohols, diols, and so forth. Several purely chemical synthetic approaches have been proposed to afford these compounds, together with some organocatalytic strategies (thiazolium-based carboligations, proline alpha-hydroxylations, and so forth). However, many of these chemical approaches are not straightforward, lack selectivity, or are economically unattractive because of the large number of chemical steps required (usually combined with low enantioselectivities). In this Account, we describe three different biocatalytic approaches that have been developed to efficiently produce alpha-hydroxy ketones: (i) The use of thiamine diphosphate-dependent lyases (ThDP-lyases) to catalyze the umpolung carboligation of aldehydes. Enantiopure alpha-hydroxy ketones are formed from inexpensive aldehydes with this method. Some lyases with a broad substrate spectrum have been successfully characterized. Furthermore, the use of biphasic media with recombinant whole cells overexpressing lyases leads to productivities of approximately 80-100 g/L with high enantiomeric excesses (up to >99%). (ii) The use of hydrolases to produce alpha-hydroxy ketones by means of (in situ) dynamic kinetic resolutions (DKRs). Lipases are able to successfully resolve racemates, and many outstanding examples have been reported. However

  16. Conductivity enhancement of sulfonated poly(ether ketone ketone) blends using electric field structuring techniques

    NASA Astrophysics Data System (ADS)

    Gasa, Jeffrey V.; Shaw, Montgomery T.

    2004-03-01

    Binary blends composed of an ion-containing polymer and a secondary component were cast under an applied elec. field to produce membranes with anisotropic morphologies. The ion-containing polymer was sulfonated poly(ether ketone ketone) (SPEKK) and the secondary component was either poly(ether imide) (PEI) or styrene-acrylonitrile (SAN) copolymer. A range of compositions and sulfonation levels were studied using this blend system. Optical and SEM micrographs of the resulting membranes showed columnar structures that were oriented along the direction of the field. It was found that electric field alignment only occurs when SPEKK is the dispersed phase but not when it is the matrix. The results show that the conductivities of the membranes that were cast under an electric field were significantly higher than those of the membranes cast without electric field. The conductivity measurements were interpreted in terms of a composite equation with structure-dependent parameters.

  17. 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.

  18. Intermittent trickling bed filter for the removal of methyl ethyl ketone and methyl isobutyl ketone.

    PubMed

    Farnazo, Danvir Mark C; Nisola, Grace M; Han, Mideok; Yoo, Namjong; Chung, Wook-Jin

    2012-05-01

    Biodegradations of methyl ethyl ketone and methyl isobutyl ketone were performed in intermittent biotrickling filter beds (ITBF) operated at two different trickling periods: 12 h/day (ITBF-12) and 30 min/day (ITBF-0.5). Ralstonia sp. MG1 was able to degrade both ketones as evidenced by growth kinetic experiments. Results show that trickling period is an important parameter to achieve high removal performance and to maintain the robustness of Ralstonia sp. MG1. Overall, ITBF-12 outperformed ITBF-0.5 regardless of the target compound. ITBF-12 had high performance recovery at various inlet gas concentrations. The higher carbon dioxide production rates in ITBF-12 suggest higher microbial activity than in ITBF-0.5. Additionally, lower concentrations of absorbed volatile organic compound (VOC) in trickling solutions of ITBF-12 systems also indicate VOC removal through biodegradation. Pressure drop levels in ITBF-12 were relatively higher than in ITBF-0.5 systems, which can be attributed to the decrease in packed bed porosity as Ralstonia sp. MG1 grew well in ITBF-12. Nonetheless, the obtained pressure drop levels did not have any adverse effect on the performance of ITBF-12. Biokinetic constants were also obtained which indicated that ITBF-12 performed better than ITBF-0.5 and other conventional biotrickling filter systems.

  19. Olfactory Psychometric Functions for Homologous 2-Ketones

    PubMed Central

    Cometto-Muñiz, J. Enrique; Abraham, Michael H.

    2009-01-01

    We measured concentration-detection (i.e., psychometric) odor functions for the homologous ketones propanone (acetone), 2-pentanone, 2-heptanone, and 2-nonanone. Under a forced-choice procedure, stimuli were presented via an 8-channel air-dilution olfactometer that allowed natural sampling of the odorant and whose output was quantified by gas chromatography. Subjects (17 to 22 per compound) comprised young adults from both genders, all normosmics and nonsmokers. A sigmoid (logistic) equation tightly fitted group and individual functions. The odor detection threshold (ODT) was the concentration detectable at halfway (P=0.5) between chance (P=0.0) and perfect (P=1.0) detection. Odor sensitivity increased (i.e., thresholds decreased) from acetone to heptanone, remaining constant for nonanone. This relative trend was also observed in previous work and in odor thresholds compilations, but the absolute ODTs obtained here were consistently at the lower end of those reported before. Interindividual variability of ODTs was about one order of magnitude. These odor functions measured behaviorally in humans were obtained at vapor concentrations 1,000 times lower than functions measured via activation, with similar 2-ketones, of receptor neurons converging into individual olfactory glomeruli of mice, visualized with calcium sensitive dyes. Odorant concentrations presented as vapors (as in behavioral studies) and those presented as liquids (as in cellular/tissue studies) can be rendered equivalent via liquid-vapor partition coefficients and, then, compared in relative olfactory potency. These comparisons can reveal how sensitivity is progressively shaped across levels of the neural pathway. PMID:19428635

  20. Olfactory psychometric functions for homologous 2-ketones.

    PubMed

    Cometto-Muñiz, J Enrique; Abraham, Michael H

    2009-07-19

    We measured concentration-detection (i.e., psychometric) odor functions for the homologous ketones propanone (acetone), 2-pentanone, 2-heptanone, and 2-nonanone. Under a forced-choice procedure, stimuli were presented via an 8-channel air-dilution olfactometer that allowed natural sampling of the odorant and whose output was quantified by gas chromatography. Subjects (17-22 per compound) comprised young adults from both genders, all normosmics and nonsmokers. A sigmoid (logistic) equation tightly fitted group and individual functions. The odor detection threshold (ODT) was the concentration detectable at halfway (P=0.5) between chance (P=0.0) and perfect (P=1.0) detection. Odor sensitivity increased (i.e., thresholds decreased) from acetone to heptanone, remaining constant for nonanone. This relative trend was also observed in previous work and in odor thresholds compilations, but the absolute ODTs obtained here were consistently at the lower end of those reported before. Interindividual variability of ODTs was about 1 order of magnitude. These odor functions measured behaviorally in humans were obtained at vapor concentrations 1000 times lower than functions measured via activation, with similar 2-ketones, of receptor neurons converging into individual olfactory glomeruli of mice, visualized with calcium sensitive dyes. Odorant concentrations presented as vapors (as in behavioral studies) and those presented as liquids (as in cellular/tissue studies) can be rendered equivalent via liquid-vapor partition coefficients and, then, compared in relative olfactory potency. These comparisons can reveal how sensitivity is progressively shaped across levels of the neural pathway.

  1. Engineering of bacterial methyl ketone synthesis for biofuels.

    PubMed

    Goh, Ee-Been; Baidoo, Edward E K; Keasling, Jay D; Beller, Harry R

    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.

  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. Direct α-alkylation of ketones with alcohols in water.

    PubMed

    Xu, Guoqiang; Li, Qiong; Feng, Jiange; Liu, Qiang; Zhang, Zuojun; Wang, Xicheng; Zhang, Xiaoyun; Mu, Xindong

    2014-01-01

    The direct α-alkylation of ketones with alcohols has emerged as a new green protocol to construct C-C bonds with H2 O as the sole byproduct. In this work, a very simple and convenient Pd/C catalytic system for the direct α-alkylation of ketones with primary alcohols in pure water is developed. Based on this catalytic system, aqueous mixtures of dilute acetone, 1-butanol, and ethanol (mimicking ABE fermentation products) can be directly transformed into C5 -C11 or longer-chain ketones and alcohols, which are precursors to fuels. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  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

    2014-12-05

    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.

  5. Bauer Ketones 23 and 24 from Echinacea paradoxa var. paradoxa Inhibit Lipopolysaccharide-induced Nitric Oxide, Prostaglandin E2 and Cytokines in RAW 264.7 Mouse Macrophages

    PubMed Central

    Zhang, Xiaozhu; Rizshsky, Ludmila; Hauck, Catherine; Qu, Luping; Widrlechner, Mark P.; Nikolau, Basil J.; Murphy, Patricia A.; Birt, Diane F.

    2011-01-01

    Among the nine Echinacea species, E. purpurea, E. angustifolia and E. pallida, have been widely used to treat the common cold, flu and other infections. In our study, ethanol extracts of these three Echinacea species and E. paradoxa, including its typical variety, E. paradoxa var. paradoxa, were screened in lipopolysaccharide (LPS)-stimulated macrophage cells to assess potential anti-inflammatory activity. Echinacea paradoxa var. paradoxa, rich in polyenes/polyacetylenes, was an especially efficient inhibitor of LPS-induced production of nitric oxide (NO), prostaglandin E2 (PGE2), interleukin-1 beta (IL-1β) and interleukin-6 (IL-6) by 46%, 32%, 53% and 26%, respectively, when tested at 20 μg/ml in comparison to DMSO control. By bioactivity-guided fractionation, pentadeca-8Z-ene-11, 13-diyn-2-one (Bauer ketones 23, compound 1) and pentadeca-8Z, 13Z-dien-11-yn-2-one (Bauer ketone 24, compound 2) from E. paradoxa var. paradoxa were found primarily responsible for inhibitory effects on NO and PGE2 production. Moreover, Bauer ketone 24 (compound 2) was the major contributor to inhibition of inflammatory cytokine production in LPS-induced mouse macrophage cells. These results provide a rationale for exploring the medicinal effects of the Bauer ketone-rich taxon, E. paradoxa var. paradoxa, and confirm the anti-inflammatory properties of Bauer ketones 23 and 24. PMID:22133644

  6. Elaboration of diaryl ketones into naphthalenes fused on two or four sides: a naphthoannulation procedure.

    PubMed

    Donovan, Patrick M; Scott, Lawrence T

    2004-03-17

    Transition metal-catalyzed double ring closures of 1,1-diaryl-2,2-diethynylethylenes yield polycyclic aromatic hydrocarbons and heterocycles that contain a newly formed naphthalene ring system embedded in a larger polycyclic network. The diynes required for this procedure are readily synthesized from diaryl ketones by the Corey-Fuchs olefination and subsequent Sonogashira coupling with trimethylsilylacetylene followed by desilylation. This procedure provides easy access to new compounds such as 3,11-di-tert-butyl[4]helicene and 1,8,9-perinaphthothioxanthene. Double naphthoannulation of 9,10-anthraquinone by this procedure closes four new benzene rings in a single operation to give coronene, although the yield in this case is presently low.

  7. Synthesis of Dipyridyl Ketone Isonicotinoyl Hydrazone Copper(II) Complex: Structure, Anticancer Activity and Anticancer Mechanism.

    PubMed

    Deng, JunGang; Chen, Wei; Deng, Hang

    2016-11-01

    In an effort to better understand the biological efficacy of the tridentate aroyl hydrazone Cu(II) complexes, the Cu(II) complex of di-2-pyridyl ketone isonicotinoyl hydrazone ligand (HL), {[Cu(L)(H2O)]·H2O·NO3}n (C1) was synthesized and characterized. Single crystal X-ray study reveals that complex C1 forms 1D zigzag chains in solid state. In water, the hydrolysis of the 1D zigzag chains was observed, and finally formation of monomeric species. In vitro studies revealed that complex C1 showed significantly more anticancer activity than the ligand alone. Investigation of the anticancer mechanisms of C1, confirmed that the Cu(II) complex exhibit a strong capacity to promote productions of reactive oxygen species (ROS), leading to caspase-dependent apoptotic cell death.

  8. Water-enhanced solvation of organic solutes in ketone and ester solvents

    SciTech Connect

    Lee, J.H.; Brunt, V. van; King, C.J. . Dept. of Chemical Engineering Lawrence Berkeley Lab., CA )

    1994-05-01

    Previous research has shown that the solubilities of dicarboxylic acids in certain electron-donor solvents are substantially increased in the presence of water. Information on solubilities, liquid-liquid equilibria and maximum-boiling ternary azeotropes was screened so as to identify other systems where codissolved water appears to enhance solvation of organic solutes in solvents. Several carboxylic acids, an alcohol, diols, and phenols were selected for examination as solutes in ketone and ester solvents. Effects of water upon solute solubilities and volatilities were measured. Results showed that water-enhanced solvation is greatest for carboxylic acids. Solute activity coefficients decreased by factors of 2--3, 6--8, and 7--10 due to the presence of water for mono-, di and tricarboxylic acids, respectively. Activity coefficients decreased by a factor of about 1.5 for ethanol and 1,2-propanediol as solutes. Water-enhanced solvation of phenols is small, when existent.

  9. Direct β-functionalization of cyclic ketones with aryl ketones via the merger of photoredox and organocatalysis.

    PubMed

    Petronijević, Filip R; Nappi, Manuel; MacMillan, David W C

    2013-12-11

    The direct β-coupling of cyclic ketones with aryl ketones has been achieved via the synergistic combination of photoredox catalysis and organocatalysis. Diaryl oxymethyl or aryl-alkyl oxymethyl radicals, transiently generated via single-electron reduction of ketone precursors, readily merge with β-enaminyl radical species, generated by photon-induced enamine oxidation, to produce γ-hydroxyketone adducts. Experimental evidence indicates that two discrete reaction pathways can be operable in this process depending upon the nature of the ketyl radical precursor and the photocatalyst.

  10. Direct β-Functionalization of Cyclic Ketones with Aryl Ketones via the Merger of Photoredox and Organocatalysis

    PubMed Central

    Petronijević, Filip R.; Nappi, Manuel

    2014-01-01

    The direct β-coupling of cyclic ketones with aryl ketones has been achieved via the synergistic combination of photoredox catalysis and organocatalysis. Diaryl oxymethyl or aryl–alkyl oxymethyl radicals, transiently generated via single-electron reduction of ketone precursors, readily merge with β-enaminyl radical species – generated by photon-induced enamine oxidation – to produce γ-hydroxyketone adducts. Experimental evidence indicates that two discrete reaction pathways can be operable in this process depending upon the nature of the ketyl radical precursor and the photocatalyst. PMID:24237366

  11. Asymmetric organocatalytic Michael addition of ketones to vinyl sulfone.

    PubMed

    Zhu, Qiang; Cheng, Lili; Lu, Yixin

    2008-12-21

    Highly enantioselective organocatalytic Michael addition of ketones to vinyl sulfone catalyzed by a cinchona alkaloid-derived primary amine is reported for the first time; the described synthetic methodology was applied to the synthesis of sodium cyclamate.

  12. Synthesis and Applications of Hajos-Parrish Ketone Isomers.

    PubMed

    Eagan, James M; Hori, Masahiro; Wu, Jianbin; Kanyiva, Kyalo Stephen; Snyder, Scott A

    2015-06-26

    Numerous natural products possess ring systems and functionality for which Hajos-Parrish ketone isomers with a transposed methyl group (termed "iso-Hajos-Parrish ketones") would be of value. However, such building blocks have not been exploited to the same degree as the more typical Hajos-Parrish hydrindane. An efficient three-step synthesis of such materials was fueled by a simple method for the rapid preparation of highly functionalized cyclopentenones, several of which are new chemical entities that would be challenging to access through other approaches. Furthermore, one iso-Hajos-Parrish ketone was converted into two distinct natural product analogues and one natural product. As one indication of the value of these new building blocks, that latter target was obtained in 10 steps, having previously been accessed in 18 steps using the Hajos-Parrish ketone. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Enantioselective rhodium(I)-catalyzed hydrogenation of trifluoromethyl ketones.

    PubMed

    Kuroki, Y; Sakamaki, Y; Iseki, K

    2001-02-08

    [figure: see text] The asymmetric hydrogenation of trifluoromethyl ketones to yield chiral alpha-trifluoromethyl alcohols with enantiomeric excesses up to 98% was achieved in the presence of chiral rhodium-(amidephosphine-phosphinite) complexes.

  14. Bleaching of kraft plus using dioxiranes: Structural effect of ketones

    SciTech Connect

    Chen, J.; Wearing, J.T.

    1996-10-01

    Recent developments in totally chlorine-free (TCF) bleaching of kraft pulps have led to a new finding showing that dimethyldioxirane (DMD), formed by reaction of peroxymonosulphate with acetone, is a very effective and selective bleaching agent. Because of the high volatility of acetone, careful design and special equipment are needed for the DMD bleaching process in order to meet operational safety, health and emission control requirements. Other ketones are considered as alternatives to acetone for dioxirane bleaching; however, the use of alternative ketones exhibits different responses in bleaching compared to acetone. This paper examines the bleaching performance of a number of selected ketones in light of different chemical structures and properties of the ketones as well as bleaching variables.

  15. Novel ketone diet enhances physical and cognitive performance

    PubMed Central

    Murray, Andrew J.; Knight, Nicholas S.; Cole, Mark A.; Cochlin, Lowri E.; Carter, Emma; Tchabanenko, Kirill; Pichulik, Tica; Gulston, Melanie K.; Atherton, Helen J.; Schroeder, Marie A.; Deacon, Robert M. J.; Kashiwaya, Yoshihiro; King, M. Todd; Pawlosky, Robert; Rawlins, J. Nicholas P.; Tyler, Damian J.; Griffin, Julian L.; Robertson, Jeremy; Veech, Richard L.; Clarke, Kieran

    2016-01-01

    Ketone bodies are the most energy-efficient fuel and yield more ATP per mole of substrate than pyruvate and increase the free energy released from ATP hydrolysis. Elevation of circulating ketones via high-fat, low-carbohydrate diets has been used for the treatment of drug-refractory epilepsy and for neurodegenerative diseases, such as Parkinson’s disease. Ketones may also be beneficial for muscle and brain in times of stress, such as endurance exercise. The challenge has been to raise circulating ketone levels by using a palatable diet without altering lipid levels. We found that blood ketone levels can be increased and cholesterol and triglycerides decreased by feeding rats a novel ketone ester diet: chow that is supplemented with (R)-3-hydroxybutyl (R)-3-hydroxybutyrate as 30% of calories. For 5 d, rats on the ketone diet ran 32% further on a treadmill than did control rats that ate an isocaloric diet that was supplemented with either corn starch or palm oil (P < 0.05). Ketone-fed rats completed an 8-arm radial maze test 38% faster than did those on the other diets, making more correct decisions before making a mistake (P < 0.05). Isolated, perfused hearts from rats that were fed the ketone diet had greater free energy available from ATP hydrolysis during increased work than did hearts from rats on the other diets as shown by using [31P]-NMR spectroscopy. The novel ketone diet, therefore, improved physical performance and cognitive function in rats, and its energy-sparing properties suggest that it may help to treat a range of human conditions with metabolic abnormalities.—Murray, A. J., Knight, N. S., Cole, M. A., Cochlin, L. E., Carter, E., Tchabanenko, K., Pichulik, T., Gulston, M. K., Atherton, H. J., Schroeder, M. A., Deacon, R. M. J., Kashiwaya, Y., King, M. T., Pawlosky, R., Rawlins, J. N. P., Tyler, D. J., Griffin, J. L., Robertson, J., Veech, R. L., Clarke, K. Novel ketone diet enhances physical and cognitive performance. PMID:27528626

  16. Novel ketone diet enhances physical and cognitive performance.

    PubMed

    Murray, Andrew J; Knight, Nicholas S; Cole, Mark A; Cochlin, Lowri E; Carter, Emma; Tchabanenko, Kirill; Pichulik, Tica; Gulston, Melanie K; Atherton, Helen J; Schroeder, Marie A; Deacon, Robert M J; Kashiwaya, Yoshihiro; King, M Todd; Pawlosky, Robert; Rawlins, J Nicholas P; Tyler, Damian J; Griffin, Julian L; Robertson, Jeremy; Veech, Richard L; Clarke, Kieran

    2016-12-01

    Ketone bodies are the most energy-efficient fuel and yield more ATP per mole of substrate than pyruvate and increase the free energy released from ATP hydrolysis. Elevation of circulating ketones via high-fat, low-carbohydrate diets has been used for the treatment of drug-refractory epilepsy and for neurodegenerative diseases, such as Parkinson's disease. Ketones may also be beneficial for muscle and brain in times of stress, such as endurance exercise. The challenge has been to raise circulating ketone levels by using a palatable diet without altering lipid levels. We found that blood ketone levels can be increased and cholesterol and triglycerides decreased by feeding rats a novel ketone ester diet: chow that is supplemented with (R)-3-hydroxybutyl (R)-3-hydroxybutyrate as 30% of calories. For 5 d, rats on the ketone diet ran 32% further on a treadmill than did control rats that ate an isocaloric diet that was supplemented with either corn starch or palm oil (P < 0.05). Ketone-fed rats completed an 8-arm radial maze test 38% faster than did those on the other diets, making more correct decisions before making a mistake (P < 0.05). Isolated, perfused hearts from rats that were fed the ketone diet had greater free energy available from ATP hydrolysis during increased work than did hearts from rats on the other diets as shown by using [(31)P]-NMR spectroscopy. The novel ketone diet, therefore, improved physical performance and cognitive function in rats, and its energy-sparing properties suggest that it may help to treat a range of human conditions with metabolic abnormalities.-Murray, A. J., Knight, N. S., Cole, M. A., Cochlin, L. E., Carter, E., Tchabanenko, K., Pichulik, T., Gulston, M. K., Atherton, H. J., Schroeder, M. A., Deacon, R. M. J., Kashiwaya, Y., King, M. T., Pawlosky, R., Rawlins, J. N. P., Tyler, D. J., Griffin, J. L., Robertson, J., Veech, R. L., Clarke, K. Novel ketone diet enhances physical and cognitive performance.

  17. Inhibition of serine proteases by peptidyl fluoromethyl ketones

    SciTech Connect

    Imperiali, B.; Abeles, R.H.

    1986-07-01

    Peptidyl fluoromethyl ketones that are specific inhibitors of the serine proteases ..cap alpha..-chymotrypsin and porcine pancreatic elastase were synthesized. By analogy with the corresponding aldehydes it is assumed that the fluoromethyl ketones react with the ..gamma..-OH group of the active site serine to form a stable hemiacetal. /sup 19/F NMR studies of the chymotrypsin-bound trifluoromethyl ketone inhibitors Ac-Leu-ambo-Phe-CF/sub 3//sup 1/ and Ac-ambo-Phe-CF/sub 3/ clearly indicate that the carbonyl carbon is tetrahedral at the active site of the enzyme. The inhibitor is bound as either the stable hydrat or the hemiacetal, involving the active site serine. The effect of varying the number of amino acid residues in the peptidyl portion of the inhibitor and the number of fluorines in the fluoromethyl ketone moiety is examined. In the series of trifluoromethyl ketone elastase inhibitors, the lowering of K/sub i/ concomitant with the change from a dipeptide analogue to a tetrapeptide analogue correlates well with the variation in V/K for hydrolysis of the corresponding amide substrates. This trend is indicative of the inhibitors acting as transition-state analogues. In addition to chain length, the number of fluorine substituents also affects the K/sub i/. In the case of chymotrypsin, the K/sub i/ for Ac-Leu-ambo-Phe-CF/sub 3/ is 30-fold lower than that for Ac-Leu-ambo-Phe-CF/sub 2/H. With elastase this trend is not as profound. In all cases, however, the difluoro- and trifluoromethyl ketones are better inhibitors than the monofluoromethyl and nonfluorinated analogues. This improvement must be associated with both the degree of hydration of the fluoromethyl ketones and the significant effect that fluorine substitution has on lowering the first pK/sub a/ of the hemiacetal hydroxyl. The monofluoromethyl ketone inhibitor of chymotrypsin, Ac-Leu-ambo-Phe-CFH/sub 2/, is a weak competitive inhibitor.

  18. Regulated workplace ketones and their interference in the PFBHA method for aldehydes.

    PubMed

    Lin, Y W; Hee, S S

    2000-11-01

    Ketones are the major positive interferences for an aldehyde dynamic air sampler that consists of 200-mg 20 percent (w/w) O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine hydrochloride (PFBHA) on Tenax TA contained in a Pyrex tube 7-mm OD, 5-mm ID, and 70-mm in length, that utilizes a personal battery-powered pump at 10-50 mL/min. The ketone O-oxime derivatives were synthesized to allow absolute quantitation of O-oximes formed during sampling. Wet spiking allowed ketone recoveries to be found. Ketone vapors of known concentrations were generated statically in Tedlar gas bags. The O-oximes were desorbed with hexane, and an aliquot injected for gas chromatographic analysis on a nonpolar capillary column with mass spectrometric or electron capture detection. Gas phase recoveries up to 200 ppm-hour loadings exceeded 75 percent at 25 degrees C for chloroacetone, cyclohexanone, diacetone alcohol, diethyl ketone, dipropyl ketone, ethyl butyl ketone, methyl amyl ketone, methyl butyl ketone, 2-methylcyclohexanone, methyl ethyl ketone, methyl isobutyl ketone, methyl isopropyl ketone, and methyl propyl ketone. The recoveries for acetophenone, 2-chloroacetophenone, and ethyl amyl ketone were lower than 75 percent, and were caused by steric hindrance. Sampling for both aldehydes and ketones is recommended at 10 mL/min for TLV concentrations.

  19. 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.

  20. Additional vinyl ketones and their pyranyl ketones in gonyleptid harvestmen (Arachnida: Opiliones) suggest these metabolites are widespread in this family.

    PubMed

    Wouters, Felipe C; Rocha, Daniele F O; Gonçalves, Caroline C S; Machado, Glauco; Marsaioli, Anita J

    2013-09-27

    Four species of gonyleptid harvestmen, Acanthogonyleptes pulcher, Gonyleptes saprophilus (Gonyleptinae), Sodreana barbiellini, and Sodreana leprevosti (Sodreaninae), were examined by GC-MS and ¹³H NMR. All of these species release vinyl ketones, and three of them produce the corresponding pyranyl ketones, which are presumed hetero-Diels-Alder (HDA) dimers. The vinyl ketones 5-methyl-1-hexen-3-one, rac-4-methyl-1-hexen-3-one, and (S)-4-methyl-1-hexen-3-one were synthesized. Natural 4-methyl-1-hexen-3-one is present as a single stereoisomer and has the R-configuration. Vinyl ketone dimers (HDA dimers) were also observed in the scent gland exudate and characterized by HRMS, ¹³C NMR, and ¹H NMR chemical shifts of the pyranyl moiety.

  1. Safety assessment of MIBK (methyl isobutyl ketone).

    PubMed

    Johnson, Wilbur

    2004-01-01

    MIBK (Methyl Isobutyl Ketone) is an aliphatic ketone that functions as both a denaturant and solvent in cosmetic products. Current use in cosmetic products is very limited, but MIBK is reported to be used in one nail correction pen (volume = 3 ml) at a concentration of 21%. The maximum percutaneous absorption rate in guinea pigs is 1.1 micromol/min/cm2 at 10 to 45 min. Metabolites include 4-hydroxy-4-methyl-2-pentanone (oxidation product) and 4-methyl-2-pentanol (4-MPOL) (reduction product). Values for the serum half-life and total clearance time of MIBK in animals were 66 min and 6 h, respectively. In clinical tests, most of the absorbed MIBK had been eliminated from the body 90 min post exposure. MIBK was not toxic via the oral or dermal route of exposure in acute, short-term, or subchronic animal studies, except that nephrotoxicity was observed in rats dosed with 1 g/kg in a short-term study. MIBK was an ocular and skin irritant in animal tests. Ocular irritation was noted in 12 volunteers exposed to 200 ppm MIBK for 15 min in a clinical test. A depression of the vestibulo-oculomotor reflex was seen with intravenous infusion of MIBK (in an emulsion) at 30 microM/kg/min in female rats. The no-observed-effect level in rats exposed orally to MIBK was 50 mg/kg. Both gross and microscopic evidence of lung damage were reported in acute inhalation toxicity studies in animals. Short-term and subchronic inhalation exposures (as low as 100 ppm) produced effects in the kidney and liver that were species and sex dependent. Dermal doses of 300 or 600 mg/kg for 4 months in rats produced reduced mitotic activity in hair follicles, increased thickness of horny and granular cell layers of the epidermis, a decrease in the number of reactive centers in follicles (spleen), an increase in the number of iron-containing pigments in the area of the red pulp (spleen), and a reduction in the lipid content of the cortical layer of the adrenal glands. Neuropathological changes in the most

  2. 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.

  3. Induction of the apolipoprotein AI gene by fasting: a relationship with ketosis but not with ketone bodies.

    PubMed

    Haas, M J; Reinacher, D; Pun, K; Wong, N C; Mooradian, A D

    2000-12-01

    Apolipoprotein AI (apoAI) expression is inversely related to the incidence of atherosclerosis. ApoAI expression is also influenced by the nutritional state and diabetes. We used both cell culture and animal models to examine the effect of fasting and ketoacidosis on apoAI gene expression. Two days of food deprivation in rats increased hepatic and intestinal apoAI mRNA by 2.6- and 2.3-fold, respectively (P < .05). The absolute concentration of plasma apoAI did not change. However, the plasma apoAI concentration relative to the plasma concentration of serum proteins was increased 23% (P < .05). In fasting rats, there was a significant positive correlation between the serum beta-hydroxybutyrate concentration and hepatic or intestinal apoAI mRNA level. Despite this correlation, changes in apoAI mRNA are probably not mediated by ketone bodies, since neither hepatic nor intestinal apoAI mRNA levels were altered in rats maintained on a ketogenic diet for 10 days or treated with isobutyramide, an orally active ketone analog. In addition, the activity of the rat apoAI promoter was not altered in Hep G2 cells treated with isobutyramide or fatty acids or exposed to hypoglycemic conditions, while dexamethasone increased promoter activity 1.9-fold (P < .05). These data indicate that metabolic changes other than ketone bodies, such as an increase in plasma glucocorticoids, may account for starvation-induced expression of apoAI.

  4. 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.

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

    SciTech Connect

    Kanetomo, Takuya; Ishida, Takayuki

    2016-02-01

    We synthesized [Ln{sup III}(hfac){sub 3}(H{sub 2}O)(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 (λ{sub ex} = 360 nm) were improved to 57 and 35%, respectively, from that of the starting material [TbI{sup III}(hfac){sub 3}(H{sub 2}O){sub 2}] (28% at λ{sub ex} = 370 nm). Similarly, the quantum yields for Eu-DTBK and -BP were 8 and 15%, respectively, with λ{sub ex} = 400 nm, while that of the starting material [EuI{sup III}(hfac){sub 3}(H{sub 2}O){sub 2}] was 4% at λ{sub ex}=400 nm.

  6. Cerebral metabolic adaptation and ketone metabolism after brain injury.

    PubMed

    Prins, Mayumi L

    2008-01-01

    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.

  7. 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

  8. 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

  9. Free Volume in Glassy Poly(arylene Ether Ketone)s

    NASA Technical Reports Server (NTRS)

    Hinkley, J. A.; Eftekhari, A.; Crook, R. A.; Jensen, B. J.; Singh, J. J.

    1996-01-01

    Amorphous polyarylene ether ketones were examined in the glassy state by positron annihilation lifetime spectroscopy ( PALS ) and in the melt by standard rheological techniques. Specimens were well-characterized fractions of two isomeric structures. PALS clearly shows that the polymer with meta linkages in its backbone contains larger voids (greater than 0.25 nm radius). Thus despite their similar bulk densities, the two materials must pack very differently on a local scale. On the other hand, the free volumes inferred from the WLF treatment of melt viscosity data are practically identical in both materials ca. 4% at T(sub g). The comparison between techniques sheds some light on the distribution of free volume.

  10. Synthesis and biological activity of brassinolide and its 22 beta, 23 beta-isomer: novel plant growth-promoting steroids.

    PubMed

    Thompson, M J; Mandava, N B; Meudt, W J; Lusby, W R; Spaulding, D W

    1981-11-01

    Brassinolide (2 alpha, 3 alpha, 22 alpha, 23 alpha-tetrahydroxy-24 alpha-methyl -B-homo-7-oxa-5 alpha-cholestan-6-one), a novel plant growth-promoting steroid isolated from rape pollen, and its hitherto unknown 22 beta, 23 beta-isomer were synthesized from a C-24 epimeric 60:40 mixture of 22-dehydroxampesterol (24 alpha-methyl) and brassicasterol (24 beta-methyl) from oysters. The method of synthesis favored the formation of the 22 beta, 23 beta-isomer by better than 4:1. Comparative plant growth-promoting capabilities of brassinolide, both natural and synthetic, and its three side chain cis-glycolic isomers in the bean second internode bioassay showed that the natural and synthetic brassinolides were equally active and caused splitting of the internode at the 0.1 microgram level. The least active was the 22 beta, 23 beta-isomer of brassinolide. The isomers with the 22 alpha, 23 alpha and 24 alpha, and the 22 beta, 23 beta and 24 beta configurations were highly active and were required at about 10 times the concentration of brassinolide to cause the same physiological response. In the bean first internode bioassay, an auxin-induced growth test system which employs isolated bean plant segments, the isomer with 22 beta, 23 beta and 24 beta configuration caused a greater response than brassinolide. Two of the four tetrahydroxy ketones obtained in the synthesis of the isomers were also active in both assays.

  11. Pd-catalyzed enantioselective intramolecular α-arylation of α-substituted cyclic ketones: facile synthesis of functionalized chiral spirobicycles.

    PubMed

    Fan, Lulu; Takizawa, Shinobu; Takeuchi, Yoshiki; Takenaka, Kazuhiro; Sasai, Hiroaki

    2015-05-07

    Catalytic synthesis of chiral spirocyclic ketones was accomplished via the Pd-catalyzed intramolecular α-arylation of α-substituted cyclic ketones. The obtained spirocyclic ketone could be converted into a bifunctional organocatalyst.

  12. Ambient Temperature Synthesis of High Enantiopurity N-Protected Peptidyl Ketones by Peptidyl Thiol Ester–Boronic Acid Cross-Coupling

    PubMed Central

    Yang, Hao; Li, Hao; Wittenberg, Rüdiger; Egi, Masahiro; Huang, Wenwei; Liebeskind, Lanny S.

    2009-01-01

    α-Amino acid thiol esters derived from N-protected mono-, di-, and tripeptides couple with aryl, π-electron-rich heteroaryl, or alkenyl boronic acids in the presence of stoichiometric Cu(I) thiophene-2-carboxylate (CuTC) and catalytic Pd2(dba)3/triethylphosphite to generate the corresponding N-protected peptidyl ketones in good to excellent yields and in high enantiopurity. Triethylphosphite plays a key role as a supporting ligand by mitigating an undesired palladium-catalyzed decarbonylation-β-elimination of the α-amino thiol esters. The peptidyl ketone synthesis proceeds at room temperature under non-basic conditions and demonstrates a high tolerance to functionality. PMID:17263394

  13. Mono-, di-, and triaryl substituted tetrahydropyrans as cyclooxygenase-2 and tumor growth inhibitors. Synthesis and biological evaluation.

    PubMed

    Singh, Palwinder; Bhardwaj, Atul

    2010-05-13

    Rationally designed tetrahydropyrans (THPs) carrying one, two, or three aryl rings and other substituents were synthesized by the allylation of beta-hydroxy ketones followed by iodocyclization. It has been observed that compounds with one aryl ring on THP are moderate inhibitors of cyclooxygenase-1 (COX-1) (IC(50) = 0.3 microM) and cyclooxygenase-2 (IC(50) = 0.17 microM) with poor selectivity index (SI = 2-3) for COX-2. The presence of two aryl rings enhanced their inhibitory activities for COX-2 (IC(50) = 0.9-5.5 nM). Selectivity for COX-2 over COX-1 also increased (SI = 50-1900), while triaryl substituted THPs, along with high inhibition (IC(50) = 0.57-4.0 nM), also exhibited excellent selectivity for COX-2 over COX-1 (SI = 3200-44000). Similar to the experimental results of increased COX-2 inhibition and selectivity with the increase in the size of the molecule, their docking in the active sites of COX-1 and COX-2 also showed same trend. Seven compounds from the category of di- and triaryl substituted THPs exhibited average GI(50) over all the human tumor cell lines in the range 1.6-3.2 microM and showed in vitro therapeutic indices of 8-17.

  14. Synthesis and Applications of iso-Hajos–Parrish Ketones**

    PubMed Central

    Eagan, James M.; Hori, Masahiro; Wu, Jianbin; Kanyiva, Kyalo Stephen; Snyder, Scott A.

    2015-01-01

    Although numerous natural products possess ring systems and functionality for which “iso-Hajos–Parrish” ketones would be of value, such building blocks have not been exploited to the same degree as the more typical Hajos–Parrish hydrindane. Herein we outline an efficient three-step synthesis of such materials fueled by a simple method for the rapid preparation of highly functionalized cyclopentenones, several of which are new chemical entities that would be challenging to access through other approaches. We then show how one iso-Hajos–Parrish ketone can be converted into two distinct natural product analogs as well as one natural product. As one indication of the value of these new building blocks, that latter target was obtained in 10 steps, having previously been accessed in 18 steps using the Hajos–Parrish ketone. PMID:25974879

  15. 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. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. A practical catalytic asymmetric addition of alkyl groups to ketones.

    PubMed

    García, Celina; LaRochelle, Lynne K; Walsh, Patrick J

    2002-09-18

    Many catalysts will promote the asymmetric addition of alkylzinc reagents to aldehydes. In contrast, there are no reports of additions to ketones that are both general and highly enantioselective. We describe herein a practical catalytic asymmetric addition of ethyl groups to ketones. The catalyst is derived from reaction of camphor sulfonyl chloride and trans-1,2-diaminocyclohexane. The resulting diketone is reduced with NaBH4 to give the C2-symmetric exo diastereomer. Use of this ligand with titanium tetraisopropoxide and dialkylzinc at room temperature results in enantioselective addition of the alkyl group to the ketone. The resulting tertiary alcohols are isolated with high enantiomeric excess (all cases give greater than 87% ee, except one). The reaction has been run with 37 mmol (5 g) 3-methylacetophenone and 2 mol % catalyst to afford 73% yield of the resulting tertiary alcohol with 99% ee.

  17. Modified nanocrystal cellulose/fluorene-containing sulfonated poly(ether ether ketone ketone) composites for proton exchange membranes

    NASA Astrophysics Data System (ADS)

    Wei, Yingcong; Shang, Yabei; Ni, Chuangjiang; Zhang, Hanyu; Li, Xiaobai; Liu, Baijun; Men, Yongfeng; Zhang, Mingyao; Hu, Wei

    2017-09-01

    Highly sulfonated poly(ether ether ketone ketone)s (SFPEEKKs) with sulfonation degrees of 2.34 (SFPEEKK5) and 2.48 (SFPEEKK10) were synthesized through the direct sulfonation of a fluorene-containing poly(ether ether ketone ketone) under a relatively mild reaction condition. Using the solution blending method, sulfonated nanocrystal cellulose (sNCC)-enhanced SFPEEKK composites (SFPEEKK/sNCC) were successfully prepared for investigation as proton exchange membranes. Transmission electron microscopy showed that sNCC was uniformly distributed in the composite membranes. The properties of the composite membranes, including thermal stability, mechanical properties, water uptake, swelling ratio, oxidative stability and proton conductivity were thoroughly evaluated. Results indicated that the insertion of sNCC could contribute to water management and improve the mechanical performance of the membranes. Notably, the proton conductivity of SFPEEKK5/sNCC-5 was as high as 0.242 S cm-1 at 80 °C. All data proved the potential of SFPEEKK/sNCC composites for proton exchange membranes in medium-temperature fuel cells.

  18. 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

  19. Copper-catalyzed synthesis of α-trifluoromethylthio-substituted ketones.

    PubMed

    Huang, Yangjie; He, Xing; Lin, Xiaoxi; Rong, Mingguang; Weng, Zhiqiang

    2014-06-20

    The CF3S-substituted moiety serves as an important structural element in many bioactive molecules. A versatile copper catalyst that allowed for trifluoromethylthiolation of primary and secondary α-bromoketones is described. The reaction with readily available elemental sulfur and CF3SiMe3 afforded a broad scope and moderate to good yields of α-trifluoromethylthio-substituted ketones. This procedure represents a very operationally simple yet powerful strategy for the synthesis of α-trifluoromethylthio-substituted ketones, a useful and versatile class of synthetic synthons.

  20. Chromium(II)-catalyzed enantioselective arylation of ketones

    PubMed Central

    Wang, Gang; Sun, Shutao; Mao, Ying; Xie, Zhiyu

    2016-01-01

    The chromium-catalyzed enantioselective addition of carbo halides to carbonyl compounds is an important transformation in organic synthesis. However, the corresponding catalytic enantioselective arylation of ketones has not been reported to date. Herein, we report the first Cr-catalyzed enantioselective addition of aryl halides to both arylaliphatic and aliphatic ketones with high enantioselectivity in an intramolecular version, providing facile access to enantiopure tetrahydronaphthalen-1-ols and 2,3-dihydro-1H-inden-1-ols containing a tertiary alcohol. PMID:28144349

  1. Enantioselective Organocatalytic α-Fluorination of Cyclic Ketones

    PubMed Central

    Kwiatkowski, Piotr; Beeson, Teresa D.; Conrad, Jay C.

    2011-01-01

    The first highly enantioselective α-fluorination of ketones using organocatalysis has been accomplished. The long-standing problem of enantioselective ketone α-fluorination via enamine activation has been overcome via high-throughput evaluation of a new library of amine catalysts. The optimal system, a primary amine functionalized Cinchona alkaloid, allows the direct and asymmetric α-fluorination of a variety of carbo- and heterocyclic substrates. Furthermore, this protocol also provides diastereo-, regio- and chemoselective catalyst control in fluorinations involving complex carbonyl systems. PMID:21247133

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

    PubMed

    Lim, Hee Nam; Dong, Guangbin

    2015-12-07

    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.

  3. Induced axial chirality in biocatalytic asymmetric ketone reduction.

    PubMed

    Agudo, Rubén; Roiban, Gheorghe-Doru; Reetz, Manfred T

    2013-02-06

    Catalytic asymmetric reduction of prochiral ketones of type 4-alkylidene cyclohexanone with formation of the corresponding axially chiral R-configurated alcohols (up to 99% ee) was achieved using alcohol dehydrogenases, whereas chiral transition-metal catalysts fail. Reversal of enantioselectivity proved to be possible by directed evolution based on saturation mutagenesis (up to 98% ee (S)). Utilization of ketone with a vinyl bromide moiety allows respective R- and S-alcohols to be exploited as key compounds in Pd-catalyzed cascade reactions.

  4. Rhodium Catalyzed Intramolecular C-H Insertion of α-Aryl-α-diazo Ketones

    PubMed Central

    Taber, Douglass F.; Tian, Weiwei

    2011-01-01

    Direct diazo transfer proceeds smoothly with α-aryl ketones. The derived α-aryl-α-diazo ketones cyclize efficiently with Rh catalysis to give the corresponding α-aryl cyclopentanones. PMID:17385917

  5. Supramolecular photochemistry in beta-cyclodextrin hosts: a TREPR, NMR, and CIDNP investigation.

    PubMed

    Krumkacheva, Olesya A; Gorelik, Vitaly R; Bagryanskaya, Elena G; Lebedeva, Natalia V; Forbes, Malcolm D E

    2010-06-01

    A systematic investigation of the photochemistry and ensuing radical chemistry of three guest ketones encapsulated in randomly methylated beta-cyclodextrin (beta-CD) hosts is reported. Dibenzyl ketone (DBK), deoxybenzoin (DOB), and benzophenone (BP) triplet states are rapidly formed after photolysis at 308 nm. Time-resolved electron paramagnetic resonance (TREPR) spectroscopy, steady-state NMR spectroscopy, and time-resolved chemically induced nuclear polarization (TR-CIDNP) experiments were performed on the ketone/CD complexes and on the ketones in free solution for comparison. The major reactivity pathways available from these excited states are either Norrish I alpha-cleavage or H-atom abstraction from the interior of the CD capsule or the solvent. The DOB triplet state undergoes both reactions, whereas the DBK triplet shows exclusively alpha-cleavage and the BP triplet shows exclusively H-atom abstraction. Radical pairs are observed in beta-CDs by TREPR, consisting of either DOB or BP ketyl radicals with sugar radicals from the CD interior. The TREPR spectra acquired in CDs are substantially broadened due to strong spin exchange. The electron spin polarization mechanism is mostly due to S-T(0) radical pair mechanism (RPM) in solution but changes to S-T(-) RPM in the CDs due to the large exchange interaction. The TR-CIDNP results confirm the reactivity patterns of all three ketones, and DOB shows strong nuclear spin polarization from a novel rearrangement product resulting from the alpha-cleavage reaction.

  6. Chemoselective synthesis of highly substituted 1,2-allenyl ketones, furans, and 2-alkynyl ketones from reaction of lithium selenolates with 1-(1-alkynyl)cyclopropyl ketones and electrophiles.

    PubMed

    Xu, Jianfeng; Zhu, Shugao; Wu, Luling; Huang, Xian

    2012-05-14

    A homo-Michael addition reaction of lithium selenolates with 1-(1-alkynyl)cyclopropyl ketones and the subsequent reaction with electrophiles such as PhSeBr, NFSI and NCS is reported. Based on the nature of electrophiles, this reaction may afford highly substituted 1,2-allenyl ketones or furans (E(+) = PhSe(+)) and 2-alkynyl ketones (E(+) = F(+), Cl(+), active halides) as the final products, respectively.

  7. Catalytic Asymmetric Methallylation of Ketones with an (H8-BINOLate)Ti-Based Catalyst

    PubMed Central

    Kim, Jeung Gon; Camp, Elizabeth H.; Walsh, Patrick J.

    2008-01-01

    The first catalytic asymmetric methallylation of ketones is reported. The catalyst, which is generated from titanium tetraisopropoxide, H8-BINOL, isopropanol, and tetramethallylstannane, reacts with ketones in acetonitrile to afford tertiary homoallylic alcohols in fair to excellent yields (55-99%) and fair to high enantioselectivities (46-90%). Ozonolysis of the resulting products provides access to chiral β-hydroxy ketones, which are not readily prepared from direct asymmetric aldol reaction of acetone with ketones. PMID:16986913

  8. Diene-ligated iridium catalyst for allylation reactions of ketones and imines.

    PubMed

    Barker, Timothy J; Jarvo, Elizabeth R

    2009-03-05

    [Ir(cod)Cl](2) is a highly reactive catalyst for allylation reactions of ketones using allylboronic ester. Mechanistic experiments are consistent with formation of a nucleophilic allyliridium(I) complex that is activated by the diene ligand toward attack of a ketone. Aryl and alkyl ketones react smoothly at room temperature. Aldimines also undergo allylation under these reaction conditions, requiring increased reaction times relative to the corresponding ketones.

  9. Tandem Aldol Condensation – Platinacycle-Catalyzed Addition Reactions of Aldehydes, Methyl Ketones and Arylboronic Acids

    PubMed Central

    Liao, Yuan-Xi; Hu, Qiao-Sheng

    2013-01-01

    Tandem aldol condensation of aldehydes with methyl ketones followed by anionic four-electron donor-based (Type I) platinacycle-catalyzed addition reactions of arylboronic acids to form β-arylated ketones is described. Good to excellent yields of β-arylated ketones were obtained for the tandem reactions of aromatic/aliphatic aldehydes, methyl ketones and arylboronic acids, and moderate yields were observed for the tandem reaction with α, β-unsaturated aldehydes as the aldehyde source. PMID:23335856

  10. Tandem Aldol Condensation - Platinacycle-Catalyzed Addition Reactions of Aldehydes, Methyl Ketones and Arylboronic Acids.

    PubMed

    Liao, Yuan-Xi; Hu, Qiao-Sheng

    2012-10-01

    Tandem aldol condensation of aldehydes with methyl ketones followed by anionic four-electron donor-based (Type I) platinacycle-catalyzed addition reactions of arylboronic acids to form β-arylated ketones is described. Good to excellent yields of β-arylated ketones were obtained for the tandem reactions of aromatic/aliphatic aldehydes, methyl ketones and arylboronic acids, and moderate yields were observed for the tandem reaction with α, β-unsaturated aldehydes as the aldehyde source.

  11. A One-Pot Synthesis of 2-Aminopyrimidines from Ketones, Arylacetylenes, and Guanidine.

    PubMed

    Schmidt, Elena Yu; Tatarinova, Inna V; Protsuk, Nadezhda I; Ushakov, Igor' A; Trofimov, Boris A

    2017-01-06

    The three-component reaction of ketones, arylacetylenes, and guanidine catalyzed by the KOBu(t)/DMSO system leads to 2-aminopyrimidines in up to 80% yield. Depending on structure of the starting ketones, the aromatization of intermediate dihydropyrimidines occurs either with loss of hydrogen molecules or methylbenzenes. The latter process takes place in the ketones, in which one of the substituents is not a methyl group. The reaction conditions are tolerable for dialkyl-, aryl(hetaryl) alkyl-, and cycloalkyl ketones.

  12. Catalyst-free dehydrative α-alkylation of ketones with alcohols: green and selective autocatalyzed synthesis of alcohols and ketones.

    PubMed

    Xu, Qing; Chen, Jianhui; Tian, Haiwen; Yuan, Xueqin; Li, Shuangyan; Zhou, Chongkuan; Liu, Jianping

    2014-01-03

    Direct dehydrative α-alkylation reactions of ketones with alcohols are now realized under simple, practical, and green conditions without using external catalysts. These catalyst-free autocatalyzed alkylation methods can efficiently afford useful alkylated ketone or alcohol products in a one-pot manner and on a large scale by CC bond formation of the in situ generated intermediates with subsequent controllable and selective Meerwein-Pondorf-Verley-Oppenauer-type redox processes. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Lipid, ketone body and oxidative metabolism in the African lungfish, Protopterus dolloi following 60 days of fasting and aestivation.

    PubMed

    Frick, Natasha Therese; Bystriansky, Jason Scott; Ip, Yuen Kwong; Chew, Shit Fun; Ballantyne, James Stuart

    2008-09-01

    The potential importance of lipids and ketone bodies as fuels in the African lungfish, Protopterus dolloi, and the role of oxidative metabolism, were examined under control, fasted and aestivated conditions. In aestivating but not fasting lungfish, the activities of citrate synthase (CS) and cytochrome c oxidase (CCO) (enzymes of oxidative metabolism) showed tissue-specific changes. Significant reductions in CS activity occurred in the kidney, heart, gill and muscle, and in CCO in the liver and kidney tissues. Aestivation, but not fasting, also had a tissue-specific effect on mitochondrial state 3 respiration rates (using succinate as a substrate), with a >50% reduction in the liver, yet no change within muscle mitochondria. There is no indication that enzymes involved in lipid catabolism are up-regulated during periods of fasting or aestivation; however, both 3-hydroxyacyl CoA dehydrogenase (HOAD) and carnitine palmitoyl CoA transferase (CPT) activities were sustained in the liver despite the approximately 42% reduction in CCO activity, potentially indicating lipid metabolism is of importance during aestivation. Lungfish are able to utilize both the d- and l-stereoisomers of the ketone body beta-hydroxybutyrate (beta-HB); however, beta-HB does not appear to be an important fuel source during aestivation or fasting as no changes were observed in beta-HB tissue levels. This study demonstrates that an important aspect of metabolic depression during aestivation in lungfish is the tissue-specific down regulation of enzymes of aerobic metabolism while maintaining the activities of enzymes in pathways that supply substrates for aerobic metabolism.

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

    USDA-ARS?s Scientific Manuscript database

    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...

  15. 40 CFR 721.10413 - Fluorinated dialkyl ketone (generic) (P-10-135).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Fluorinated dialkyl ketone (generic... 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 the...

  16. 40 CFR 721.10417 - Biphenyl alkyl morpholino ketone (generic) (P-11-338).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Biphenyl alkyl morpholino ketone... 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 for...

  17. 40 CFR 721.10417 - Biphenyl alkyl morpholino ketone (generic) (P-11-338).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Biphenyl alkyl morpholino ketone... 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 for...

  18. 40 CFR 721.10413 - Fluorinated dialkyl ketone (generic) (P-10-135).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Fluorinated dialkyl ketone (generic... 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 the...

  19. 40 CFR 721.10413 - Fluorinated dialkyl ketone (generic) (P-10-135).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Fluorinated dialkyl ketone (generic... 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 the...

  20. Acyl hydrazides as acyl donors for the synthesis of diaryl and aryl alkyl ketones.

    PubMed

    Akhbar, Ahmed R; Chudasama, Vijay; Fitzmaurice, Richard J; Powell, Lyn; Caddick, Stephen

    2014-01-21

    In this communication we describe a novel strategy for the formation of valuable diaryl and aryl alkyl ketones from acyl hydrazides. A wide variety of ketones are prepared and the mild reaction conditions allow for the use of a range of functionalities, especially in the synthesis of diaryl ketones.

  1. 40 CFR 721.10417 - Biphenyl alkyl morpholino ketone (generic) (P-11-338).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Biphenyl alkyl morpholino ketone... 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 for...

  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. © 2014 The Authors. Diabetic Medicine © 2014 Diabetes UK.

  3. Diversity-oriented synthesis of chromenes via metal-free domino reactions from ketones and phenols.

    PubMed

    Xue, Wei-Jian; Li, Qi; Gao, Fang-fang; Zhu, Yan-ping; Wang, Jun-gang; Zhang, Wei; Wu, An-Xin

    2012-08-13

    Functionalized chromenes have been synthesized via highly selective metal-free domino reactions from ketones and phenols. 2H-Chromenes, 4H-chromenes, spiran and benzocyclopentane can be respectively prepared starting from the corresponding cyclic ketones, aryl methyl ketones, acetone, and 3-pentanone.

  4. 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.

  5. 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.

  6. 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.

  7. 21 CFR 862.1435 - Ketones (nonquantitative) test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 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...

  8. Ketone Body Metabolic Enzyme OXCT1 Regulates Prostate Cancer Chemoresistance

    DTIC Science & Technology

    2015-12-01

    and cellular energy homeostasis . Analysis of patient data indicated that higher OXCT1 levels are associated with docetaxel chemotherapy resistance...knock down induced metabolic inefficiency upon docetaxel treatment Since OXCT1 is a metabolic enzyme involved in energy homeostasis , next, to...ketone body metabolism and cellular energy homeostasis . Analysis of our previous data from patient needle biopsy samples indicated that higher

  9. Chiral Ketone and Iminium Catalysts for Olefin Epoxidation

    NASA Astrophysics Data System (ADS)

    Wong, O. Andrea; Shi, Yian

    Organo-catalyzed asymmetric epoxidation has received much attention in the past 30 years and significant progress has been made for various types of olefins. This review will cover the advancement made in the field of chiral ketone and chiral iminium salt-catalyzed epoxidations.

  10. Process for conversion of levulinic acid to ketones

    DOEpatents

    Dagle, Vanessa M.; Dagle, Robert A.

    2017-05-30

    A method for generating desired platform chemicals from feedstocks such as cellulosic biomass feedstocks containing levulinic acid by decarboxylating a feed stock comprising levulinic acid to generate ketones. This is done by passing a feed stock comprising levulinic acid in a gas phase over a non-precious metal catalyst on a neutral support.

  11. Ketone body metabolism and sleep homeostasis in mice.

    PubMed

    Chikahisa, Sachiko; Shimizu, Noriyuki; Shiuchi, Tetsuya; Séi, Hiroyoshi

    2014-04-01

    A link has been established between energy metabolism and sleep homeostasis. The ketone bodies acetoacetate and β-hydroxybutyrate, generated from the breakdown of fatty acids, are major metabolic fuels for the brain under conditions of low glucose availability. Ketogenesis is modulated by the activity of peroxisome proliferator-activated receptor alpha (PPARα), and treatment with a PPAR activator has been shown to induce a marked increase in plasma acetoacetate and decreased β-hydroxybutyrate in mice, accompanied by increased slow-wave activity during non-rapid eye movement (NREM) sleep. The present study investigated the role of ketone bodies in sleep regulation. Six-hour sleep deprivation increased plasma ketone bodies and their ratio (acetoacetate/β-hydroxybutyrate) in 10-week-old male mice. Moreover, sleep deprivation increased mRNA expression of ketogenic genes such as PPARα and 3-hydroxy-3-methylglutarate-CoA synthase 2 in the brain and decreased ketolytic enzymes such as succinyl-CoA: 3-oxoacid CoA transferase. In addition, central injection of acetoacetate, but not β-hydroxybutyrate, markedly increased slow-wave activity during NREM sleep and suppressed glutamate release. Central metabolism of ketone bodies, especially acetoacetate, appears to play a role in the regulation of sleep homeostasis.

  12. Multicentric evaluation of eight glucose and four ketone blood meters.

    PubMed

    Guimont, Marie-Christine; Desjobert, Hélène; Fonfrède, Michèle; Vitoux, Dominique; Benoist, Jean-Francois; Launay, Jean-Marie; Peoc'h, Katell; Lefèvre, Guillaume

    2015-12-01

    High precision meters for blood glycemia are mandatory for monitoring glucose status in patients, avoiding both hypo- and hyper-glycemia. Health care providers routinely used in both out- and in-patients point-of-care measurements of glucose and ketone. These measurements, frequently used for medical decisions, are known to be less accurate than those performed in laboratories. Our aim was to evaluate, within the frame of an Assistance Publique-Hôpitaux de Paris (AP-HP) multicentric study, the performances of eight glucose and four ketone meters, either connected or non-connected to a laboratory software. Glucose meter accuracy, precision, correlation with plasma glucose determined in central laboratories and hematocrit interferences were determined according to the ISO 15197:2003 norm. The same norm was applied for the determination of accuracy, precision and recovery of ketone meters for B-hydroxybutyrate measurements. Among those meters, seven were considered as acceptable for glucose measurement and two for ketone measurement. Since all meters do not fit clinically relevant criteria, meters' performances have to be evaluated before use in clinical practice. Copyright © 2015 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

  13. Enzymatic method for determining ketone body ratio in arterial blood.

    PubMed

    Uno, S; Takehiro, O; Tabata, R; Ozawa, K

    1995-12-01

    We have developed a new, sensitive, and rapid method for measuring the ketone body concentration in arterial blood and determining the arterial blood ketone body ratio. The procedure involves the sequential use of the enzymes 3-hydroxybutyrate dehydrogenase (3-HBDH; EC 1.1.1.30) and NADH oxidase, followed by a color-generating reaction with the hydrogen peroxide produced by the oxidase reaction. The amount of oxidized chromogen produced is proportional to the 3-hydroxybutyrate (3-HBA) concentration. The acetoacetate (AcAc) concentration is obtained after complete conversion of the AcAc to 3-HBA, in the presence of 3-HBDH. The total 3-HBA concentration is measured and then subtracted from the total ketone body concentration to give the AcAc concentration. This procedure may be applied to plasma samples and the absorbance change measured with an automated chemistry analyzer. Ketone body concentration may be determined over the range 0 to 400 mumol/L. The analysis takes approximately 12 min and requires only 30 microL of plasma.

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

    USDA-ARS?s Scientific Manuscript database

    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...

  15. Dielectric behavior of some small ketones as ideal polar molecules.

    PubMed

    Shikata, Toshiyuki; Yoshida, Nao

    2012-05-17

    The dielectric behaviors of some small symmetric ketone molecules, including acetone, 3-pentanone, cyclopentanone, 4-heptanone, and cyclohexanone, were investigated as a function of temperature (T) over a wide frequency range from 50 MHz (3.14 × 10(8) s(-1), in angular frequency) to 3 THz (1.88 × 10(13) s(-1)). The temperature dependencies of the rotational diffusion times (τ(r)) determined using (17)O NMR spin-lattice relaxation time (T(1)) measurements and viscosities of the ketones were also examined. The obtained temperature dependencies of the parameters for the ketones were compared with those of ideal polar molecules, which obey the Stokes-Einstein-Debye (SED) relationship without the formation of intermolecular dimeric associations and without orientational correlations between dipoles (molecular axes), that is, free rotation. Kirkwood correlation factors (g(K)) of only acetone and 3-pentanone were close to unity over a wide temperature range, whereas those of other ketones were obviously less than unity. These results revealed that no correlations exist between the rotational motions of dipoles in acetone and 3-pentanone, as expected in ideal polar molecules. However, other ketones exhibited orientational correlations in their dipoles because of dipole-dipole interactions via antiparallel configurations. Furthermore, because acetone and 3-pentanone satisfied the SED relationship and because their microscopic dielectric relaxation times (τ(μ)), which were calculated from the determined dielectric relaxation times (τ(D)) via the relationship τ(μ) = τ(D)g(K)(-1), were identical to 3τ(r) and were proportional to Vη(k(B)T)(-1) over the wide temperature range examined, where V, k(B), and η represent the effective molecular volume, Boltzmann's constant, and the viscosity of the liquid molecules, respectively, these two ketone molecules behave as ideal polar molecules. In addition, other ketones not significantly larger than acetone and 3-pentanone in

  16. Studies on elimination pathways of β-halovinyl ketones leading to allenyl and propargyl ketones and furans under the action of mild bases.

    PubMed

    Kim, Hun Young; Li, Jian-Yuan; Oh, Kyungsoo

    2012-12-21

    The elimination pathway of stereochemically defined β-halovinyl ketones has been investigated using a mild base, NEt(3), leading to the formation of allenyl ketones and propargyl ketones. A preferential α-vinyl enolization of (E)-β-chlorovinyl ketones has been observed where a nonplanar s-cis conformation is proposed as a dominant conformation as opposed to a planar s-cis conformation of (Z)-β-chlorovinyl ketones. Other eliminative pathways, such as concerted syn- and anti-E2 as well as γ-deprotonation, are excluded on the basis of the deuterium isotope studies. The synthetic utility of the elimination reaction of β-chlorovinyl ketones was further demonstrated for a one-pot synthesis of 2,5-disubstituted furans in the presence of 1 mol % CuCl.

  17. 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

  18. 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.

  19. Regiodivergent halogenation of (E)-β-chlorovinyl ketones via soft α-vinyl enolization strategy.

    PubMed

    Kim, Hun Young; Lee, Seokwoo; Kim, Sanghee; Oh, Kyungsoo

    2015-02-06

    The soft α-vinyl enolization of (E)-β-chlorovinyl ketones was investigated in the presence of various halogen electrophiles. Depending on the nature of halogen electrophiles, the selective formation of three products, namely α,α-dichloropropargyl ketones, α,γ-dihaloallenyl ketones, and 3-halofurans, was observed. The observed regiodivergent nucleophilic pathways of (E)-β-chlorovinyl ketones demonstrate the diversity-oriented synthesis strategy in which the nucleophilic reactivity of (E)-β-chlorovinyl ketones can be selectively modulated by the choice of suitable hard and soft electrophiles.

  20. Asymmetric epoxidation of unsaturated ketones catalyzed by heterobimetallic rare earth-lithium complexes bearing phenoxy-functionalized chiral diphenylprolinolate ligand.

    PubMed

    Qian, Qinqin; Tan, Yufang; Zhao, Bei; Feng, Tao; Shen, Qi; Yao, Yingming

    2014-09-05

    Four novel heterobimetallic complexes [REL2]{[(THF)3Li]2(μ-Cl)} stabilized by chiral phenoxy-functionalized prolinolate (RE = Yb (1), Y (2), Sm (3), Nd (4), H2L = (S)-2,4-di-tert-butyl-6-[[2-(hydroxydiphenylmethyl)pyrrolidin-1-yl]methyl]phenol have been synthesized and characterized. These readily available complexes are highly active in catalyzing the epoxidation of α,β-unsaturated ketones, while the enantioselectivity varies according to the ionic radii of the rare earth center. A series of chalcone derivatives were converted to chiral epoxides in 80 → 99% ee at 0 °C using TBHP as the oxidant in the presence of 10 mol % of 1.

  1. Di-μ-bromido-bis-[bromido(di-2-pyridylmethane-diol-κN,N')copper(II)] dihydrate.

    PubMed

    Westcott, Barry L; Kopp-Vaughn, Kristin M; Daniels, Lee M; Zeller, Matthias

    2008-08-06

    The centrosymmetric title complex, [Cu(2)Br(4)(C(11)H(10)N(2)O(2))(2)]·2H(2)O, was one of three complexes isolated by slow evaporation of an acetonitrile reaction mixture of CuBr(2) with di-2-pyridyl ketone (1:1 molar ratio). The title complex contains a 1:1 metal-to-ligand ratio of copper(II) with the hydrated form of the ligand di-2-pyridylmethane-diol. The copper centers are bridged by bromide donors, leading to a Cu-Cu distance of 4.090 (6) Å. The crystals form as non-merohedral twins with two components related by a 180° rotation around the normal to [100]; the selected sample had a twin ratio of 0.63:0.37.

  2. Photoreduction and ketone-sensitized reduction of alkaloids.

    PubMed

    Görner, Helmut; Miskolczy, Zsombor; Megyesi, Mónika; Biczók, László

    2011-01-01

    The photoprocesses of berberine, palmatine, coralyne, sanguinarine, flavopereirine and ellipticine were studied in several solvents. The quantum yields Φ(Δ) of singlet molecular oxygen formation of berberine, palmatine and sanguinarine are moderate in dichloromethane (0.2-0.6) and much smaller in acetonitrile or trifluoroethanol. For the other alkaloids examined, Φ(Δ) is rather independent of solvent polarity. The direct and ketone-sensitized photolysis, using steady-state irradiation at 313 nm or 248/308 nm laser pulses, was studied by absorption and fluorescence spectroscopy. Thereby, radicals were observed yielding eventually dihydro derivatives as major products, which are thermally back-converted on admission of oxygen. The quantum yield of conversion of alkaloids to dihydroalkaloids is enhanced in the presence of triethylamine. The reaction in the presence of ketones and electron or H-atom donors has a quantum yield of close to unity.

  3. 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.

  4. Thiomethylation of ketones by sulphide-alkaline solutions and formaldehyde

    SciTech Connect

    Ulendeyeva, A.D.; Samigullin, I.I.; Nasteka, V.I.

    1993-12-31

    An investigation has been made of the thiomethylation of ketones by formaldehyde with mercaptides, sodium sulphide and their mixture. It is possible to regenerate 78-100 rel.% of the sulphide-alkaline solutions under mild conditions (20-50{degrees}C, atmospheric pressure) without feeding a catalyst, with the simultaneous production of ketosulphide concentrate - a less toxic product with properties of practical benefit. 7 refs., 2 figs., 2 tabs.

  5. 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.

  6. 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

  7. Ketone bodies alter dinitrophenol-induced glucose uptake through AMPK inhibition and oxidative stress generation in adult cardiomyocytes.

    PubMed

    Pelletier, Amélie; Coderre, Lise

    2007-05-01

    In aerobic conditions, the heart preferentially oxidizes fatty acids. However, during metabolic stress, glucose becomes the major energy source, and enhanced glucose uptake has a protective effect on heart function and cardiomyocyte survival. Thus abnormal regulation of glucose uptake may contribute to the development of cardiac disease in diabetics. Ketone bodies are often elevated in poorly controlled diabetics and are associated with increased cellular oxidative stress. Thus we sought to determine the effect of the ketone body beta-hydroxybutyrate (OHB) on cardiac glucose uptake during metabolic stress. We used 2,4-dinitrophenol (DNP), an uncoupler of the mitochondrial oxidative chain, to mimic hypoxia in cardiomyocytes. Our data demonstrated that chronic exposure to OHB provoked a concentration-dependent decrease of DNP action, resulting in 56% inhibition of DNP-mediated glucose uptake at 5 mM OHB. This was paralleled by a diminution of DNP-mediated AMP-activated protein kinase (AMPK) and p38 MAPK phosphorylation. Chronic exposure to OHB also increased reactive oxygen species (ROS) production by 1.9-fold compared with control cells. To further understand the role of ROS in OHB action, cardiomyocytes were incubated with H(2)O(2). Our results demonstrated that this treatment diminished DNP-induced glucose uptake without altering activation of the AMPK/p38 MAPK signaling pathway. Incubation with the antioxidant N-acetylcysteine partially restored DNP-mediated glucose but not AMPK/p38 MAPK activation. In conclusion, these results suggest that ketone bodies, through inhibition of the AMPK/p38 MAPK signaling pathway and ROS overproduction, regulate DNP action and thus cardiac glucose uptake. Altered glucose uptake in hyperketonemic states during metabolic stress may contribute to diabetic cardiomyopathy.

  8. Nickel-Catalyzed Cycloadditions of Unsaturated Hydrocarbons, Aldehydes, and Ketones

    PubMed Central

    Tekavec, Thomas N.

    2014-01-01

    The nickel-catalyzed cycloaddition of unsaturated hydrocarbons and carbonyls is reported. Diynes and enynes were used as coupling partners. Carbonyl substrates include both aldehdyes and ketones. Reactions of diynes and aldehydes afforded the [3, 3] electrocyclic ring-opened tautomers, rather than pyrans, in high yields. The cycloaddition reaction of enynes and aldehydes afforded two distinct products. A new carbon–carbon bond is formed, prior to a competitive β-hydrogen elimination of a nickel alkoxide, between the carbonyl carbon and either one of the carbons of the olefin or the alkyne. The steric hindrance of the enyne greatly affected the chemoselectivity of the cycloaddition of enynes and aldehydes. In some cases, dihydropyran was also formed. The scope of the cycloaddition reaction was expanded to include the coupling of enynes and ketones. No β-hydrogen elimination was observed in cycloaddition reaction of enynes and ketones. Instead, C–O bond-forming reductive elimination occurred exclusively to afford dihydropyrans in excellent yields. In all cases, complete chemoselectivity was observed; only dihydropyrans where the carbonyl carbon forms a carbon–carbon bond with a carbon of the olefin, rather than of the alkyne, were observed. All cycloaddition reactions occur at room temperature and employ nickel catalysts bearing the hindered 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene (IPr) or its saturated analogue, 1,3-bis(2,6-diisopropylphenyl)-4,5-dihydroimidazolin-2-ylidene (SIPr). PMID:18318544

  9. Aqueous oxidation of phenylurea herbicides by triplet aromatic ketones.

    PubMed

    Canonica, Silvio; Hellrung, Bruno; Müller, Pavel; Wirz, Jakob

    2006-11-01

    Excited triplet states of dissolved natural organic matter (DOM) are important players for the transformation of organic chemical contaminants in sunlit natural waters. The present study focuses on kinetics and mechanistic aspects of the transformation of phenylurea herbicides induced by well-defined excited triplet states, which have been chosen to model DOM triplet states having oxidative character. The aromatic ketones benzophenone, 3'-methoxyacetophenone, and 2-acetonaphthone were used to photogenerate their triplet states and oxidize a series of eleven substituted phenylureas. Quenching of the excited triplet states by the phenylureas was measured using laser flash photolysis in the microsecond time domain, while the oxidation kinetics of the phenylureas was followed under steady-state irradiation. Second-order rate constants for quenching and oxidation were largely identical for a given pair of ketone and phenylurea. They reached the diffusion-controlled limit (approximately 4 x 10(9) M(-1) s(-1)) and decreased with increasing free energy of electron transfer from the phenylurea to the ketone triplet. These results confirm those already obtained using phenols as the substrates to be oxidized and suggest that oxidation rates are mainly determined by the bimolecular rate constant for electron transfer, a rule that can possibly be extended to various organic contaminants. A refined estimate of the effective reduction potential of DOM excited triplet states was also obtained.

  10. Solvation of Esters and Ketones in Supercritical CO2.

    PubMed

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

    2016-02-04

    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.

  11. A first principles analysis of the hydrogenation of C1C4 aldehydes and ketones over Ru(0001)

    SciTech Connect

    Sinha, Nishant K.; Neurock, Matthew

    2012-11-01

    The structure and degree of substitution of C₁–C₄ oxygenate molecules can influence their chemisorption and reactivity on metal surfaces. Gradient-corrected periodic density functional theory calculations were carried out to analyze alkyl substituent effects on the hydrogenation of C₁–C₄ aldehydes and ketones to their corresponding alcohols. All of these aldehydes along with acetone were found to adsorb in a di-ση1η2(C,O) mode onto the Ru(0001) surface and result in rehybridization of the C=O bond. Steric hindrance from two alkyl substituents on the carbonyl backbone of methyl ethyl ketone (MEK), however, prevents it from binding di-ση1η2(C,O). It adsorbs instead atop a Ru atom in an g1(O) configuration through its oxygen atom. Hydrogenation of both aldehydes and ketones can occur through either a hydroxy or an alkoxy mechanism. The hydroxy route proceeds via the formation of the hydroxyalkyl intermediate R₁R₂C*OH by the addition of hydrogen to the oxygen of the carbonyl, whereas the alkoxy mechanism proceeds by the addition of hydrogen to the carbon end to form the alkoxy intermediate R₂CHO*). DFT calculations indicate that the activation barrier for the initial addition of hydrogen to the carbon to form the C–H bond in the alkoxy mechanism is independent of the substituent groups that are attached to the carbon center as these groups are oriented away from the surface in the transition state and thus have little influence on the activation energies. The activation barriers for the addition of hydrogen to the oxygen of the carbonyl to form the O–H bond in the hydroxy mechanism, however, was found to linearly correlate with the binding energy of the hydroxyalkyl intermediate that forms. This trend can be explained through the Brønsted–Evans–Polanyi relationship and the fact that both the hydroxyalkyl products and carbonyl reactants interact via their carbon centers and are correlated with one another. All of the carbonyls follow a

  12. Synthesis of (E)-alpha-hydroxy-beta,gamma-unsaturated amides with high selectivity from alpha,beta-epoxyamides by using catalytic samarium diiodide or triiodide.

    PubMed

    Concellón, José M; Bernad, Pablo L; Bardales, Eva

    2004-05-17

    The highly stereoselective synthesis of (E)-alpha-hydroxy-beta,gamma-unsaturated amides starting from alpha,beta-epoxyamides, by using catalytic SmI2 or SmI3, was achieved. This transformation can also be carried out by using SmI2 generated in situ from samarium powder and diiodomethane. The starting compounds 1 are easily prepared by the reaction of enolates derived from alpha-chloroamides with ketones at -78 degrees C. A mechanism to explain this transformation has been proposed. Cyclopropanation of (E)-alpha-hydroxy-beta,gamma-unsaturated amides has been performed to demonstrate their synthetic applications.

  13. Di-n-butyltin(IV) complexes derived from heterocyclic beta-diketones and N-phthaloyl amino acids: preparation, biological evaluation, structural elucidation based upon spectral [IR, NMR (1H, 13C, 19F and 119Sn)] studies.

    PubMed

    Joshi, Anurag; Verma, Shashi; Gaurb, R B; Sharma, R R

    2005-01-01

    Stable, six coordinated Bu(2)SnLA type complexes have been prepared [where LH = RCOC:C(OH)N(C(6) H(5))N:CCH(3); R = -4-F-C(6)H(4)-(L(1)H), R = -4-Cl-C(6)H(4)-(L(2)H), R= -4-Br-C(6)H(4)-(L(3)H), R=-CF(3)(L(4)H) and AH = C(O)C(6) H(4) C(O)NCHR'COOH; R'= -H(A(1)H), -CH(3)(A(2)H), -CH(CH(3))(2)(A(3)H)] by the interaction of 1:1:1 molar ratios of di-n-butyltin(IV) dichloride with corresponding organic moieties in refluxing benzene using two moles of Et(3)N as a base. In these complexes LH and AH behave as bidentate and coordination is taking place through oxygen, this is inferred from IR and (13)C NMR studies. These complexes possess tin atoms in skew trapezoidal bipyramidal geometry with the C-Sn-C angles ranging from 149.88( degrees ) to 156.84( degrees ). Some of these complexes with their corresponding organic moieties (LH, AH) were tested for their antimicrobial activities.

  14. 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.

  15. Microwave-assisted synthesis of 5-aminopyrazol-4-yl ketones and the p38(MAPK) inhibitor RO3201195 for study in Werner syndrome cells.

    PubMed

    Bagley, Mark C; Davis, Terence; Dix, Matthew C; Murziani, Paola G S; Rokicki, Michal J; Kipling, David

    2008-07-01

    5-Aminopyrazol-4-yl ketones are prepared rapidly and efficiently using microwave dielectric heating from beta-ketonitriles by treatment with N,N'-diphenylformamidine followed by heterocyclocondensation by irradiation with a hydrazine. The inhibitory activity of RO3201195 prepared by this methodology was confirmed in hTERT-immortalized HCA2 and WS dermal fibroblasts at 200nM concentration, both by ELISA and immunoblot assay, and displays excellent kinase selectivity for p38alpha MAPK over the related stress-activated kinase JNK.

  16. Aerobic dehydrogenative α-diarylation of benzyl ketones with aromatics through carbon-carbon bond cleavage.

    PubMed

    More, Nagnath Yadav; Jeganmohan, Masilamani

    2014-02-07

    Substituted benzyl ketones reacted with aromatics in the presence of K2S2O8 in CF3COOH at room temperature, yielding α-diaryl benzyl ketones through a carbon-carbon bond cleavage. In the reaction, two new carbon-carbon bonds were formed and one carbon-carbon bond was cleaved. It is very interesting that two different nucleophiles such as benzyl ketones and aromatics were coupled together without metal, which is unusual in organic synthesis.

  17. Enantioselective Pd-catalyzed allylation of acyclic α-fluorinated ketones.

    PubMed

    Wang, Wengui; Shen, Haiming; Wan, Xiao-Long; Chen, Qing-Yun; Guo, Yong

    2014-07-03

    Significant synthetic challenges remain for the asymmetric synthesis of tertiary α-fluoro ketones, which are potentially useful molecules for the development of drugs, agrochemicals, and functional materials. Herein, we describe the development of a method for the catalytic enantioselective synthesis of tertiary α-fluoro ketones via the Tsuji-Trost reaction of racemic acyclic α-fluorinated ketones. Enantioenriched acyclic α-cabonyl tertiary fluorides can be produced with the aid of a palladium/phosphinooxazoline catalyst.

  18. Regio- and Stereoselective Modification of Chiral α-Amino Ketones by Pd-Catalyzed Allylic Alkylation.

    PubMed

    Huwig, Kai; Schultz, Katharina; Kazmaier, Uli

    2015-07-27

    Chiral α-amino ketones are excellent nucleophiles for stereoselective palladium-catalyzed allylic alkylations. Both chiral as well as achiral allylic substrates can be applied, while the stereochemical outcome of the reaction is controlled by the chiral ketone enolate. The substituted amino ketones formed can be reduced stereoselectively, and up to five consecutive stereogenic centers can be obtained. This approach can be used for the synthesis of highly substituted piperidine derivatives.

  19. Exploring the clinical utility of blood ketone levels in the emergency department assessment of paediatric patients

    PubMed Central

    O'Donohoe, P B; Kessler, R; Beattie, T F

    2006-01-01

    Background Ketonuria (on standard urine testing) is a frequent finding in children presenting to emergency departments. With the advent of hand‐held ketone meters, blood ketone levels can now be rapidly quantified. Hypothesis Point of care testing (POCT) of blood ketone levels could provide clinically useful information on severity of illness in children and risk of hospital admission. Methods A prospective study using POCT of blood ketone levels in a convenience sample of children <13 years old, with a typical case mix of medical problems. Findings 186 children were studied. The range of ketone levels varied widely among this study population depending on the presenting complaint. Higher levels were noted in those presenting with anorexia or vomiting and fever. The median ketone level of the total study population was 0.2 (range 0–6.0, interquartile range 0.1–0.9) mmol/l. Ketone levels correlated poorly with discharge destination and duration of admission. However, receiver–operator characteristics for ketones as a predictor of admission were comparable to Pediatric Risk of Admission scores (area under the curve 0.64 and 0.72, respectively) and may represent an independent risk factor for admission. A ketone level >1.2 mmol/l has a positive predictive value of 66.7% for admission. Ketone levels correlated well with decreased oral intake (R2 = 0.25; p<0.001). Conclusions A strong association was found between ketone levels, decreased oral intake and fever. Although ketone levels do not correlate well with more traditional markers of illness severity, they can help to predict the requirement for admission to hospital when interpreted in the context of the presenting illness. They may have applications in both the emergency department and primary care settings. Further prospective testing is required to validate these findings. PMID:16988307

  20. 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

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

    SciTech Connect

    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 studies 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.

  2. Direct and enantioselective α-allylation of ketones via singly occupied molecular orbital (SOMO) catalysis

    PubMed Central

    Mastracchio, Anthony; Warkentin, Alexander A.; Walji, Abbas M.; MacMillan, David W. C.

    2010-01-01

    The first enantioselective organocatalytic α-allylation of cyclic ketones has been accomplished via singly occupied molecular orbital catalysis. Geometrically constrained radical cations, forged from the one-electron oxidation of transiently generated enamines, readily undergo allylic alkylation with a variety of commercially available allyl silanes. A reasonable latitude in both the ketone and allyl silane components is readily accommodated in this new transformation. Moreover, three new oxidatively stable imidazolidinone catalysts have been developed that allow cyclic ketones to successfully participate in this transformation. The new catalyst platform has also been exploited in the first catalytic enantioselective α-enolation and α-carbooxidation of ketones. PMID:20921367

  3. Stereoselective synthesis of cyclohexanones via phase transfer catalyzed double addition of nucleophiles to divinyl ketones.

    PubMed

    Silvanus, Andrew C; Groombridge, Benjamin J; Andrews, Benjamin I; Kociok-Köhn, Gabriele; Carbery, David R

    2010-11-05

    Functionalized cyclohexanones are formed in excellent yield and diastereoselectivity from a phase transfer catalyzed double addition of active methylene pronucleophiles to nonsymmetrical divinyl ketones.

  4. Gallium (III) triflate catalyzed efficient Strecker reaction of ketones and their fluorinated analogs

    PubMed Central

    Prakash, G. K. Surya; Mathew, Thomas; Panja, Chiradeep; Alconcel, Steevens; Vaghoo, Habiba; Do, Clement; Olah, George A.

    2007-01-01

    The synthesis of α-aminonitriles and their fluorinated analogs has been carried out in high yield and purity by the Strecker reaction from the corresponding ketones and amines with trimethylsilyl cyanide using gallium triflate in dichloromethane. Monofluoro-, difluro-, or trifluoromethyl groups can be incorporated into the α-aminonitrile product by varying the nature of the fluorinated ketones. Study with various fluorinated and nonfluorinated ketones reveals that the choice of proper catalyst and the solvent system (suitable metal triflates as a catalyst and dichloromethane as a solvent) plays the key role in the direct Strecker reactions of ketones. PMID:17360416

  5. Palladium-catalysed mono-α-alkenylation of ketones with alkenyl tosylates.

    PubMed

    Wu, Yong; Fu, Wai Chung; Chiang, Chien-Wei; Choy, Pui Ying; Kwong, Fuk Yee; Lei, Aiwen

    2017-01-16

    The first example of palladium-catalysed selective mono-α-alkenylation of ketones with alkenyl tosylates is described. In the presence of a Pd/XPhos catalyst system (0.1-1.0 mol%), the reaction provides mono-α-alkenylated ketones in good yields and exhibits excellent substrate tolerance. Highly congested, tri- and tetra-substituted alkenyl tosylates react smoothly and even problematic heteroaryl and aliphatic ketones are applicable substrates. Notably, small β,γ-unsaturated ketones are successfully prepared using acetone as a simple three-carbon feedstock.

  6. Ketone Bodies and Exercise Performance: The Next Magic Bullet or Merely Hype?

    PubMed

    Pinckaers, Philippe J M; Churchward-Venne, Tyler A; Bailey, David; van Loon, Luc J C

    2017-03-01

    Elite athletes and coaches are in a constant search for training methods and nutritional strategies to support training and recovery efforts that may ultimately maximize athletes' performance. Recently, there has been a re-emerging interest in the role of ketone bodies in exercise metabolism, with considerable media speculation about ketone body supplements being routinely used by professional cyclists. Ketone bodies can serve as an important energy substrate under certain conditions, such as starvation, and can modulate carbohydrate and lipid metabolism. Dietary strategies to increase endogenous ketone body availability (i.e., a ketogenic diet) require a diet high in lipids and low in carbohydrates for ~4 days to induce nutritional ketosis. However, a high fat, low carbohydrate ketogenic diet may impair exercise performance via reducing the capacity to utilize carbohydrate, which forms a key fuel source for skeletal muscle during intense endurance-type exercise. Recently, ketone body supplements (ketone salts and esters) have emerged and may be used to rapidly increase ketone body availability, without the need to first adapt to a ketogenic diet. However, the extent to which ketone bodies regulate skeletal muscle bioenergetics and substrate metabolism during prolonged endurance-type exercise of varying intensity and duration remains unknown. Therefore, at present there are no data available to suggest that ingestion of ketone bodies during exercise improves athletes' performance under conditions where evidence-based nutritional strategies are applied appropriately.

  7. [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.

  8. Enantioselective Photocatalytic [3 + 2] Cycloadditions of Aryl Cyclopropyl Ketones.

    PubMed

    Amador, Adrian G; Sherbrook, Evan M; Yoon, Tehshik P

    2016-04-13

    Control of stereochemistry in photocycloaddition reactions remains a substantial challenge; almost all successful catalytic examples to date have involved [2 + 2] photocycloadditions of enones. We report a method for the asymmetric [3 + 2] photocycloaddition of aryl cyclopropyl ketones that enables the enantiocontrolled construction of densely substituted cyclopentane structures not synthetically accessible using other catalytic methods. These results show that the dual-catalyst strategy developed in our laboratory broadens synthetic chemists' access to classes of photochemical cycloadditions that have not previously been feasible in enantioselective form.

  9. Methyl isobutyl ketone as a solvent for wax deoiling

    SciTech Connect

    Larikov, V.I.; Pereverzev, A.N.; Roshchin, Y.N.; Sokolova, S.P.

    1983-09-01

    The solvency of methyl isobutyl ketone (MIBK) for use in deoiling and cold-fractionation of solid paraffin waxes is investigated by a visual polytherm method in the temperature interval 0-36 C. The capability of MIBK for precipitating solid hydrocarbons from solution was found to be greater than acetone/toluene or MEK/toluene, with only MEK better in this respect than MIBK. The quantity of wax remaining in the filtrate is examined. The critical solution temperatures are investigated and it is shown that MIBK surpasses MEK. The results obtained indicate that MIBK is extremely promising for use in processes of deoiling and cold fractionation of waxes.

  10. 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.

  11. Torquoselectivity in the Nazarov reactions of allenyl vinyl ketones.

    PubMed

    Morgan, Timothy D R; LeBlanc, Luc M; Ardagh, Giselle H; Boyd, Russell J; Burnell, D Jean

    2015-01-16

    Nazarov reactions mediated by BF3-etherate of a series of carbon-substituted allenyl vinyl ketones provided intermediates in which substituents on the termini of the allenes had rotated away from the vinyl moieties, and these intermediates were trapped by (4 + 3)-cyclizations. A computational examination of the torquoselectivity of these Nazarov reactions confirmed a kinetic preference for the observed isomers and pointed to steric interactions and the degree of allene deformation as significant factors in determining the torquoselectivity. The study also suggested that the high proportion of one geometrical isomer in the Nazarov products might also be due to some preferential trapping of the major Nazarov intermediate.

  12. 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.

  13. 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

  14. Suberosols A-D, four new sesquiterpenes with beta-caryophyllene skeletons from a Taiwanese gorgonian coral Subergorgia suberosa.

    PubMed

    Wang, Guey-Horng; Ahmed, Atallah F; Sheu, Jyh-Horng; Duh, Chang-Yih; Shen, Ya-Ching; Wang, Li-Tang

    2002-06-01

    Four new beta-caryophyllene-derived sesquiterpenes alcohols, suberosols A (1), B (2), C (3), and D (4), along with two known beta-caryophyllene-derived sesqueterpene ketones, buddledins C (5) and D (6), were isolated from a Taiwanese gorgonian coral Subergorgia suberosa. The structures of 1-4 were determined on the basis of extensive spectroscopic analyses. Cytotoxicity of these compounds toward various cancer cell lines is also described.

  15. New lupane triterpenoids from Solidago canadensis that inhibit the lyase activity of DNA polymerase beta.

    PubMed

    Chaturvedula, V S Prakash; Zhou, Bing-Nan; Gao, Zhijie; Thomas, Shannon J; Hecht, Sidney M; Kingston, David G I

    2004-12-01

    Bioassay-directed fractionation of a methyl ethyl ketone extract of Solidago canadensis L. (Asteraceae), using an assay to detect the lyase activity of DNA polymerase beta, resulted in the isolation of the four new lupane triterpenoids 1-4 and the seven known compounds lupeol, lupeyl acetate, ursolic acid, cycloartenol, cycloartenyl palmitate, alpha-amyrin acetate, and stigmasterol. The structures of the new compounds were established as 3beta-(3R-acetoxyhexadecanoyloxy)-lup-20(29)-ene (1), 3beta-(3-ketohexadecanoyloxy)-lup-20(29)-ene (2), 3beta-(3R-acetoxyhexadecanoyloxy)-29-nor-lupan-20-one (3), and 3beta-(3-hetohexadecanoyloxy)-29-nor-lupan-20-one (4), respectively, on the basis of extensive 1D and 2D NMR spectroscopic interpretation and chemical modification studies. All 11 compounds were inhibitory to the lyase activity of DNA polymerase beta.

  16. 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.

  17. 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.

  18. Characterization of synthetic routes to 'Bromo-DragonFLY' and benzodifuranyl isopropylamine homologues utilizing ketone intermediates. Part 1: synthesis of ketone precursors.

    PubMed

    O'Connor, Richard E; Keating, John J

    2014-01-01

    Bromo-DragonFLY (BDF) and many of its analogues are misused as recreational drugs due to their potency as psychoactive substances. To date, none of the published routes to these designer amphetamines have exploited a ketone intermediate. It is well known that benzyl methyl ketone (BMK) can be employed as a precursor in the synthesis of amphetamine. Similarly, it is reasonable to assume that ketone precursors may potentially be utilized in the clandestine synthesis of BDF and its homologues. This paper describes the multifaceted synthesis of novel precursor ketones structurally related to BDF, namely benzodifuranyl propanone 16, its tetrahydrobenzodifuranyl homologue 8, and their brominated analogues 12 and 20. Their characterization by Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance spectroscopy ((1) H-NMR), carbon nuclear magnetic resonance spectroscopy ((13) C-NMR), high performance liquid chromatography (HPLC), gas chromatography (GC) and mass spectrometry (MS) is also described. Copyright © 2013 John Wiley & Sons, Ltd.

  19. Ketones prevent oxidative impairment of hippocampal synaptic integrity through KATP channels.

    PubMed

    Kim, Do Young; Abdelwahab, Mohammed G; Lee, Soo Han; O'Neill, Derek; Thompson, Roger J; Duff, Henry J; Sullivan, Patrick G; Rho, Jong M

    2015-01-01

    Dietary and metabolic therapies are increasingly being considered for a variety of neurological disorders, based in part on growing evidence for the neuroprotective properties of the ketogenic diet (KD) and ketones. Earlier, we demonstrated that ketones afford hippocampal synaptic protection against exogenous oxidative stress, but the mechanisms underlying these actions remain unclear. Recent studies have shown that ketones may modulate neuronal firing through interactions with ATP-sensitive potassium (KATP) channels. Here, we used a combination of electrophysiological, pharmacological, and biochemical assays to determine whether hippocampal synaptic protection by ketones is a consequence of KATP channel activation. Ketones dose-dependently reversed oxidative impairment of hippocampal synaptic integrity, neuronal viability, and bioenergetic capacity, and this action was mirrored by the KATP channel activator diazoxide. Inhibition of KATP channels reversed ketone-evoked hippocampal protection, and genetic ablation of the inwardly rectifying K+ channel subunit Kir6.2, a critical component of KATP channels, partially negated the synaptic protection afforded by ketones. This partial protection was completely reversed by co-application of the KATP blocker, 5-hydoxydecanoate (5HD). We conclude that, under conditions of oxidative injury, ketones induce synaptic protection in part through activation of KATP channels.

  20. Ketones Prevent Oxidative Impairment of Hippocampal Synaptic Integrity through KATP Channels

    PubMed Central

    Kim, Do Young; Abdelwahab, Mohammed G.; Lee, Soo Han; O’Neill, Derek; Thompson, Roger J.; Duff, Henry J.; Sullivan, Patrick G.; Rho, Jong M.

    2015-01-01

    Dietary and metabolic therapies are increasingly being considered for a variety of neurological disorders, based in part on growing evidence for the neuroprotective properties of the ketogenic diet (KD) and ketones. Earlier, we demonstrated that ketones afford hippocampal synaptic protection against exogenous oxidative stress, but the mechanisms underlying these actions remain unclear. Recent studies have shown that ketones may modulate neuronal firing through interactions with ATP-sensitive potassium (KATP) channels. Here, we used a combination of electrophysiological, pharmacological, and biochemical assays to determine whether hippocampal synaptic protection by ketones is a consequence of KATP channel activation. Ketones dose-dependently reversed oxidative impairment of hippocampal synaptic integrity, neuronal viability, and bioenergetic capacity, and this action was mirrored by the KATP channel activator diazoxide. Inhibition of KATP channels reversed ketone-evoked hippocampal protection, and genetic ablation of the inwardly rectifying K+ channel subunit Kir6.2, a critical component of KATP channels, partially negated the synaptic protection afforded by ketones. This partial protection was completely reversed by co-application of the KATP blocker, 5-hydoxydecanoate (5HD). We conclude that, under conditions of oxidative injury, ketones induce synaptic protection in part through activation of KATP channels. PMID:25848768

  1. [Research on utilization of phage display technology to screen chloramine ketone simulated surface point].

    PubMed

    Xiong, Yonghua; Chen, Xuelan; Liu, Xiaoxing

    2010-09-01

    Utilize phage display technology to screen chloramine ketone simulated surface point, providing the basis for establishing drug-free ELISA test system. Use the anti chloramine ketone monoclonal antibody as the ligand, and screen the Ph.D. -7(TM) phage display peptide library to select the chloramine ketone simulated surface point. After 4 rounds of screening, select the phase, which can combine the chloramines ketone monoclonal antibody with different degrees, and further, determine the positive clone with competitive inhibition of the hydrochloric chloramine ketone by the indirect competitive ELISA method. It is discovered that all the 10 phages can combine the chloramine ketone monoclonal antibody with different degrees. Use the indirect competitive ELISA method to determine, the phenomenon that 5 positive clones, among them, have competitive inhibition with the hydrochloric chloramine ketone exists. The sequencing results of those 5 positive clones show that 4 different amino acid sequenced are obtained. Tentatively judge these 4 phages display the chloramine ketone simulated antigen surface points.

  2. 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

  3. Switchable asymmetric bio-epoxidation of α,β-unsaturated ketones.

    PubMed

    Liu, Yu-Chang; Wu, Zhong-Liu

    2016-01-21

    Efficient asymmetric bio-epoxidation of electron-deficient α,β-unsaturated ketones was realized via a tandem reduction-epoxidation-dehydrogenation cascade, which proceeds in a switchable manner to afford either chiral epoxy ketones or allylic epoxy alcohols with up to >99% yield and >99%ee.

  4. Asymmetric Direct 1,2-Addition of Aryl Grignard Reagents to Aryl Alkyl Ketones.

    PubMed

    Osakama, Kazuki; Nakajima, Makoto

    2016-01-15

    The enantioselective addition of Grignard reagents to ketones was promoted by a BINOL derivative bearing alkyl chains at the 3,3'-positions. This is the first asymmetric direct aryl Grignard addition to ketones reported to date. A variety of tertiary diaryl alcohols could be obtained in high yields and enantioselectivities without using any other metal source.

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

    USDA-ARS?s Scientific Manuscript database

    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...

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

    USDA-ARS?s Scientific Manuscript database

    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...

  7. 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.

  8. Beta measurements

    NASA Technical Reports Server (NTRS)

    Schotland, R. M.; Warren, A. J.; Funariu, O. M.

    1991-01-01

    The second year's results of the BETA project research are presented. The program is divided into two areas, aerosol modification and climatology in the trade wind region and the climatology of BETA (CO2) on remote mountain top locations. Limited data is available on the aerosol climatology of the marine free troposphere (MFT) in the trade wind region. In order to study the effects of cumulus convection on the MFT values of BETA, a cloud model was developed to simulate the evolution of a typical Pacific trade wind cumulus cloud. The stages involved in this development are outlined. The assembly of the major optical components of the lidar was made. Tests were run of the spectral bandwidth of the Synrad laser when a portion of the beam is mixed with a component which has traveled 450 meters corresponding to a delay of 1.5 microsecs. The bandwidth of the beat signal was measured to be 3 KHz. The data processing system based on a parallel processing filter bank analyzer using true time squaring detectors at each filter was completed.

  9. Multi-dimensional Roles of Ketone Bodies in Fuel Metabolism, Signaling, and Therapeutics.

    PubMed

    Puchalska, Patrycja; Crawford, Peter A

    2017-02-07

    Ketone body metabolism is a central node in physiological homeostasis. In this review, we discuss how ketones serve discrete fine-tuning metabolic roles that optimize organ and organism performance in varying nutrient states and protect from inflammation and injury in multiple organ systems. Traditionally viewed as metabolic substrates enlisted only in carbohydrate restriction, observations underscore the importance of ketone bodies as vital metabolic and signaling mediators when carbohydrates are abundant. Complementing a repertoire of known therapeutic options for diseases of the nervous system, prospective roles for ketone bodies in cancer have arisen, as have intriguing protective roles in heart and liver, opening therapeutic options in obesity-related and cardiovascular disease. Controversies in ketone metabolism and signaling are discussed to reconcile classical dogma with contemporary observations.

  10. [Studies on metabolism of total terpene ketones from Swertia mussotii with human intestinal bacteria].

    PubMed

    Li, Shuang; Tian, Cheng-Wang; Wu, Shuai; Yang, Xiu-Wei; Wang, Li-Li; Zhang, Tie-Jun

    2012-12-01

    To study the metabolism of total terpene ketones from Swertia mussotii with human intestinal bacteria. Total terpene ketones were incubated with human intestinal bacteria under an anaerobic environment and at 37 degrees C. The metabolites were extracted by ethyl acetate processing, detected by HPLC-DAD method. A qualitative analysis was made for its metabolites by HPLC-MS. Eight metabolites were detected from total terpene ketones from S. mussotii with human intestinal bacteria, and two of them were preliminarily identified as gentianine and mangiferin aglycon. Total terpene ketones can be metabolized with human intestinal bacteria, which provides basis for experiments on the metabolism process total terpene ketones from S. mussotii with human intestinal bacteria.

  11. Evaluation of difluoromethyl ketones as agonists of the γ-aminobutyric acid type B (GABAB) receptor.

    PubMed

    Han, Changho; Salyer, Amy E; Kim, Eun Hoo; Jiang, Xinyi; Jarrard, Rachel E; Powers, Matthew S; Kirchhoff, Aaron M; Salvador, Tolani K; Chester, Julia A; Hockerman, Gregory H; Colby, David A

    2013-03-28

    The design, synthesis, biological evaluation, and in vivo studies of difluoromethyl ketones as GABAB agonists that are not structurally analogous to known GABAB agonists, such as baclofen or 3-aminopropyl phosphinic acid, are presented. The difluoromethyl ketones were assembled in three synthetic steps using a trifluoroacetate-release aldol reaction. Following evaluation at clinically relevant GABA receptors, we have identified a difluoromethyl ketone that is a potent GABAB agonist, obtained its X-ray structure, and presented preliminary in vivo data in alcohol-preferring mice. The behavioral studies in mice demonstrated that this compound tended to reduce the acoustic startle response, which is consistent with an anxiolytic profile. Structure-activity investigations determined that replacing the fluorines of the difluoromethyl ketone with hydrogens resulted in an inactive analogue. Resolution of the individual enantiomers of the difluoromethyl ketone provided a compound with full biological activity at concentrations less than an order of magnitude greater than the pharmaceutical, baclofen.

  12. Unusual transannular cyclization products of sarcophytoxide, a 14-membered marine cembranoid: anomalous stereochemistry of epoxide-ketone rearrangement.

    PubMed

    Nii, Keiji; Tagami, Keiko; Matsuoka, Keisuke; Munakata, Tatsuo; Ooi, Takashi; Kusumi, Takenori

    2006-07-06

    [reaction: see text] Treatment of sarcophytoxide with trimethylsilyl trifluoromethanesulfonate afforded an aromatic ketone as an unusual cyclization product. The modified Mosher's method and X-ray analysis performed on the aromatic ketone revealed that it is a 4:1 mixture of 8(R)- and 8(S)-enantiomers. It also suggested that the precursor ketone has 8(R)-configuration, which is contradictory to that expected from the ordinary epoxide-ketone rearrangement.

  13. Effects of beta-hydroxybutyric acid on bovine milk leukocytes function in vitro.

    PubMed

    Cerone, S I; Sansinanea, A S; García, M C

    2007-03-01

    The in vitro effect of different concentrations of beta-hydroxybutyric acid (betaHBA) on bovine milk leukocytes was examined. betaHBA level similar to those found in cows with clinical ketosis induced a significant inhibitory effect on the nitroblue tetrazolium reduction as a mean of assaying the metabolic integrity of macrophages after the phorbol-mirystate- acetate and opsonized zymosan stimulation. In the same way, the H2O2 production after stimulation with both soluble and particulate agents decreased significantly in 33 and 26%, respectively, compared with cells incubated without ketone bodies. This result suggests a possible fault in the microbicidal oxidative activity. The macrophage phagocytosis also decreased in cells treated with different betaHBA concentrations, in relation to that obtained from control cells. Neutrophils migration in agarose was determined, and the mean chemotactic response was higher when the cells were incubated with lower level or absence of ketone bodies. Considering the determined differences, we hypothesize that abnormally high levels of ketone bodies could produce a direct effect on leukocyte membranes. The induction of some modification on the receptor structure impairment the interaction ligand-receptor and this may be, in part, responsible for the higher susceptibility to local infections in mammary gland during subclinical and clinical ketosis.

  14. Degradation characteristics of methyl ethyl ketone by Pseudomonas sp. KT-3 in liquid culture and biofilter.

    PubMed

    Lee, Tae Ho; Kim, Jaisoo; Kim, Min-Joo; Ryu, Hee Wook; Cho, Kyung-Suk

    2006-04-01

    With ketone pollution forming an ever-growing problem, it is important to identify a ketone-degrading microorganism and establish its effect. Here, a methyl ethyl ketone (MEK)-degrading bacterium, Pseudomonas sp. KT-3, was isolated and its MEK degradation characteristics were examined in liquid cultures and a polyurethane-packed biofilter. In liquid cultures, strain KT-3 could degrade other ketone solvents, including diethyl ketone (DK), methyl propyl ketone (MPK), methyl isopropyl ketone (MIPK), methyl isobutyl ketone (MIBK), methyl butyl ketone (MBK) and methyl isoamyl ketone (MIAK). The maximum specific growth rate (mumax) of the isolate was 0.136 h(-1) in MEK medium supplemented with MEK as a sole carbon source, and kinetically, the maximum removal rate (Vm) and saturation constant (Km) for MEK were 12.28 mM g(-1)DCW h(-1) (DCW: dry cell weight) and 1.64 mM, respectively. MEK biodegradation by KT-3 was suppressed by the addition of MIBK or acetone, but not by toluene. In the tested biofilter, KT-3 exhibited a>90% removal efficiency for MEK inlet concentrations of around 500 ppmv at a space velocity (SV) of 150 h(-1). The elimination capacity of MEK was more influenced by SV than by the inlet concentration. Kinetic analysis showed that the maximum MEK removal rate (Vm) was 690 g m(-3) h(-1) and the saturation constant (Km) was 490 ppmv. Collectively, these results indicate the polyurethane sequencing batch biofilter with Pseudomonas sp. KT-3 will provide an excellent performance in the removal of gaseous MEK.

  15. Anti-diabetic activity of beta-glucans and their enzymatically hydrolyzed oligosaccharides from Agaricus blazei.

    PubMed

    Kim, Yea-Woon; Kim, Ki-Hoon; Choi, Hyun-Ju; Lee, Dong-Seok

    2005-04-01

    Beta-glucans were prepared from Agaricus blazei Murill by repeated extraction with hot water. The average molecular weights of beta-glucans were 30-50 kDa by gel filtration chromatography. Oligosaccharides (AO), derived from hydrolyzing beta-glucans with an endo-beta-(1-->6)-glucanase from Bacillus megaterium, were mainly di- and tri-saccharides. Though beta-glucans and AO both showed anti-hyperglycemic, anti-hypertriglyceridemic, anti-hypercholesterolemic, and anti-arteriosclerotic activity indicating overall anti-diabetic activity in diabetic rats, AO had about twice the activity of beta-glucans with respect to anti-diabetic activity.

  16. 40 CFR 63.61 - Deletion of methyl ethyl ketone from the list of hazardous air pollutants.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 9 2011-07-01 2011-07-01 false Deletion of methyl ethyl ketone from... Designations, Source Category List § 63.61 Deletion of methyl ethyl ketone from the list of hazardous air pollutants. The substance methyl ethyl ketone (MEK, 2-Butanone) (CAS Number 78-93-3) is deleted from the list...

  17. 40 CFR 63.61 - Deletion of methyl ethyl ketone from the list of hazardous air pollutants.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 10 2014-07-01 2014-07-01 false Deletion of methyl ethyl ketone from... Designations, Source Category List § 63.61 Deletion of methyl ethyl ketone from the list of hazardous air pollutants. The substance methyl ethyl ketone (MEK, 2-Butanone) (CAS Number 78-93-3) is deleted from the list...

  18. 40 CFR 63.61 - Deletion of methyl ethyl ketone from the list of hazardous air pollutants.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 10 2012-07-01 2012-07-01 false Deletion of methyl ethyl ketone from... Designations, Source Category List § 63.61 Deletion of methyl ethyl ketone from the list of hazardous air pollutants. The substance methyl ethyl ketone (MEK, 2-Butanone) (CAS Number 78-93-3) is deleted from the list...

  19. DMF Dimethyl Acetal as Carbon Source for α-Methylation of Ketones: A Hydrogenation-Hydrogenolysis Strategy of Enaminones.

    PubMed

    Borah, Ashwini; Goswami, Limi; Neog, Kashmiri; Gogoi, Pranjal

    2015-05-01

    A novel heterogeneous catalytic hydrogenation-hydrogenolysis strategy has been developed for the α-methylation of ketones via enaminones using DMF dimethyl acetal as carbon source. This strategy provides a very convenient route to α-methylated ketones using a variety of ketones without any base or oxidant.

  20. 40 CFR 63.61 - Deletion of methyl ethyl ketone from the list of hazardous air pollutants.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 10 2013-07-01 2013-07-01 false Deletion of methyl ethyl ketone from... Designations, Source Category List § 63.61 Deletion of methyl ethyl ketone from the list of hazardous air pollutants. The substance methyl ethyl ketone (MEK, 2-Butanone) (CAS Number 78-93-3) is deleted from the list...

  1. Aryl ketone synthesis via tandem orthoplatinated triarylphosphite-catalyzed addition reactions of arylboronic acids with aldehydes followed by oxidation.

    PubMed

    Liao, Yuan-Xi; Hu, Qiao-Sheng

    2010-10-15

    Tandem orthoplatinated triaryl phosphite-catalyzed addition reactions of arylboronic acids with aldehydes followed by oxidation to yield aryl ketones is described. 3-Pentanone was identified as a suitable oxidant for the tandem aryl ketone formation reaction. By using microwave energy, aryl ketones were obtained in high yields with the catalyst loading as low as 0.01%.

  2. 40 CFR 63.61 - Deletion of methyl ethyl ketone from the list of hazardous air pollutants.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Deletion of methyl ethyl ketone from... Designations, Source Category List § 63.61 Deletion of methyl ethyl ketone from the list of hazardous air pollutants. The substance methyl ethyl ketone (MEK, 2-Butanone) (CAS Number 78-93-3) is deleted from the list...

  3. Aryl Ketone Synthesis via Tandem Orthoplatinated Triarylphosphite-Catalyzed Addition Reactions of Arylboronic Acids with Aldehydes Followed by Oxidation

    PubMed Central

    Liao, Yuan-Xi; Hu, Qiao-Sheng

    2010-01-01

    Tandem orthoplatinated triarylphosphite-catalyzed addition reactions of arylboronic acids with aldehydes followed by oxidation to yield aryl ketones is described. 3-Pentanone was identified as a suitable oxidant for the tandem aryl ketone formation reaction. By using microwave energy, aryl ketones were obtained in high yields with the catalyst loading as low as 0.01%. PMID:20849092

  4. 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

  5. [Synthesis and immunosuppressive effects of novel phthalazine ketone derivatives].

    PubMed

    Wang, Ya-Li; Wang, Qing-He; Yang, Hong-Guang; Hao, Bo-Jun; Liang, Guo-Dong; Jiang, Chong-Guo; Cheng, Mao-Sheng

    2013-10-01

    A series of phthalazine ketone compounds were synthesized and the structures were confirmed by H NMR and HR-MS spectrum. All target compounds were obtained through 7 steps, including selective reduction, nitration, bromination, ring enlargement, reduction, Knoevenagel and acylated reaction. The compounds were evaluated for their immunosuppressive effects of T-cell proliferation and inhibitory activity of IMPDH type II in vitro, as well as their structure-activity relationship were assessed. Several compounds exhibited strong immunosuppressive properties, especially compounds 7f and 7h, with IC50 values of 0.093 micromol x L(-1) and 0.14 micromol x L(-1) respectively, which were superior to mycophenolic acid. The information obtained from the studies may be useful for further research on the immunosuppressive agents.

  6. Regulation of Ketone Body Metabolism and the Role of PPARα

    PubMed Central

    Grabacka, Maja; Pierzchalska, Malgorzata; Dean, Matthew; Reiss, Krzysztof

    2016-01-01

    Ketogenesis and ketolysis are central metabolic processes activated during the response to fasting. Ketogenesis is regulated in multiple stages, and a nuclear receptor peroxisome proliferator activated receptor α (PPARα) is one of the key transcription factors taking part in this regulation. PPARα is an important element in the metabolic network, where it participates in signaling driven by the main nutrient sensors, such as AMP-activated protein kinase (AMPK), PPARγ coactivator 1α (PGC-1α), and mammalian (mechanistic) target of rapamycin (mTOR) and induces hormonal mediators, such as fibroblast growth factor 21 (FGF21). This work describes the regulation of ketogenesis and ketolysis in normal and malignant cells and briefly summarizes the positive effects of ketone bodies in various neuropathologic conditions. PMID:27983603

  7. 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.

  8. Chain-extended poly(aryl ether ketones)

    SciTech Connect

    Robeson, L.M.; Winslow, P.A.; Matzner, M.; Harris, J.E.; Maresca, L.M.

    1992-06-09

    This patent describes a process for preparing a poly(aryl ether ketone) polymer. It comprises reacting (n) moles of HAr H with (n + 1) moles of YCOAr{sub 1}COY under Friedel-Crafts polymerization conditions; reacting the product obtained with 2XAR{sub 2}H under Friedel-Crafts polymerization conditions; reacting the product obtained with HOAr{sub 3}OH in the presence of a base and an aprotic solvent; wherein Ar and Ar{sub 1} are divalent aromatic groups, Ar{sub 2} is a divalent aromatic group wherein the substituents X and CO are in para or ortho position relative to each other, Ar{sub 3} is a residue of a dihydric phenol, X and Y are halogen, n is an integer of 1 to 50 and X is one or greater.

  9. Regulation of Ketone Body Metabolism and the Role of PPARα.

    PubMed

    Grabacka, Maja; Pierzchalska, Malgorzata; Dean, Matthew; Reiss, Krzysztof

    2016-12-13

    Ketogenesis and ketolysis are central metabolic processes activated during the response to fasting. Ketogenesis is regulated in multiple stages, and a nuclear receptor peroxisome proliferator activated receptor α (PPARα) is one of the key transcription factors taking part in this regulation. PPARα is an important element in the metabolic network, where it participates in signaling driven by the main nutrient sensors, such as AMP-activated protein kinase (AMPK), PPARγ coactivator 1α (PGC-1α), and mammalian (mechanistic) target of rapamycin (mTOR) and induces hormonal mediators, such as fibroblast growth factor 21 (FGF21). This work describes the regulation of ketogenesis and ketolysis in normal and malignant cells and briefly summarizes the positive effects of ketone bodies in various neuropathologic conditions.

  10. Synthesis of ketones from biomass-derived feedstock

    NASA Astrophysics Data System (ADS)

    Meng, Qinglei; Hou, Minqiang; Liu, Huizhen; Song, Jinliang; Han, Buxing

    2017-01-01

    Cyclohexanone and its derivatives are very important chemicals, which are currently produced mainly by oxidation of cyclohexane or alkylcyclohexane, hydrogenation of phenols, and alkylation of cyclohexanone. Here we report that bromide salt-modified Pd/C in H2O/CH2Cl2 can efficiently catalyse the transformation of aromatic ethers, which can be derived from biomass, to cyclohexanone and its derivatives via hydrogenation and hydrolysis processes. The yield of cyclohexanone from anisole can reach 96%, and the yields of cyclohexanone derivatives produced from the aromatic ethers, which can be extracted from plants or derived from lignin, are also satisfactory. Detailed study shows that the Pd, bromide salt and H2O/CH2Cl2 work cooperatively to promote the desired reaction and inhibit the side reaction. Thus high yields of desired products can be obtained. This work opens the way for production of ketones from aromatic ethers that can be derived from biomass.

  11. 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.

  12. Synthesis of ketones from biomass-derived feedstock

    PubMed Central

    Meng, Qinglei; Hou, Minqiang; Liu, Huizhen; Song, Jinliang; Han, Buxing

    2017-01-01

    Cyclohexanone and its derivatives are very important chemicals, which are currently produced mainly by oxidation of cyclohexane or alkylcyclohexane, hydrogenation of phenols, and alkylation of cyclohexanone. Here we report that bromide salt-modified Pd/C in H2O/CH2Cl2 can efficiently catalyse the transformation of aromatic ethers, which can be derived from biomass, to cyclohexanone and its derivatives via hydrogenation and hydrolysis processes. The yield of cyclohexanone from anisole can reach 96%, and the yields of cyclohexanone derivatives produced from the aromatic ethers, which can be extracted from plants or derived from lignin, are also satisfactory. Detailed study shows that the Pd, bromide salt and H2O/CH2Cl2 work cooperatively to promote the desired reaction and inhibit the side reaction. Thus high yields of desired products can be obtained. This work opens the way for production of ketones from aromatic ethers that can be derived from biomass. PMID:28139709

  13. Biofiltration of ketone compounds by a composite bead biofilter.

    PubMed

    Chan, Wu-Chung; Peng, Kang-Hong

    2008-05-01

    In this study, the biochemical kinetic behaviors of ketone compounds in a composite bead biofilter were investigated. Both microbial growth rate kg and biochemical reaction rate kd would be inhibited at higher average inlet concentration. For the microbial growth process, the inhibitive effect was the least pronounced for acetone and the order of kg value was MEK>MIPK>acetone in the average inlet concentration range of 100-150 ppm. The degree of inhibitive effect was almost the same for three ketone compounds and the order of kg value was acetone>MEK>MIPK in the average inlet concentration range of 200-300 ppm. The values of half-saturation constant Ks for acetone, MEK and MIPK were 26.80, 21.56 and 22.96 ppm, respectively. The values of maximum reaction rate Vm for acetone, MEK and MIPK were 8.55, 9.06 and 7.55 g-C/h-kg packed material, respectively. The zero-order kinetic with the diffusion rate limitation could be regarded as the most adequate biochemical reaction model. For the biochemical reaction process, the inhibitive effect was the most pronounced for MEK and the order of kd value was MEK>acetone>MIPK in the average inlet concentration range of 100-150 ppm. The degree of inhibitive effect was MIPK>MEK>acetone and the order of kd value was acetone>MEK>MIPK in the average inlet concentration range of 200-300 ppm. The maximum elimination capacity of acetone, MEK and MIPK were 0.157, 0.127 and 0.101 g-C/h-kg packed material.

  14. 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.

  15. Hypothalamic sensing of ketone bodies after prolonged cerebral exposure leads to metabolic control dysregulation

    PubMed Central

    Carneiro, Lionel; Geller, Sarah; Hébert, Audrey; Repond, Cendrine; Fioramonti, Xavier; Leloup, Corinne; Pellerin, Luc

    2016-01-01

    Ketone bodies have been shown to transiently stimulate food intake and modify energy homeostasis regulatory systems following cerebral infusion for a moderate period of time (<6 hours). As ketone bodies are usually enhanced during episodes of fasting, this effect might correspond to a physiological regulation. In contrast, ketone bodies levels remain elevated for prolonged periods during obesity, and thus could play an important role in the development of this pathology. In order to understand this transition, ketone bodies were infused through a catheter inserted in the carotid to directly stimulate the brain for a period of 24 hours. Food ingested and blood circulating parameters involved in metabolic control as well as glucose homeostasis were determined. Results show that ketone bodies infusion for 24 hours increased food intake associated with a stimulation of hypothalamic orexigenic neuropeptides. Moreover, insulinemia was increased and caused a decrease in glucose production despite an increased resistance to insulin. The present study confirms that ketone bodies reaching the brain stimulates food intake. Moreover, we provide evidence that a prolonged hyperketonemia leads to a dysregulation of energy homeostasis control mechanisms. Finally, this study shows that brain exposure to ketone bodies alters insulin signaling and consequently glucose homeostasis. PMID:27708432

  16. KETONES INHIBIT MITOCHONDRIAL PRODUCTION OF REACTIVE OXYGEN SPECIES PRODUCTION FOLLOWING GLUTAMATE EXCITOTOXICITY BY INCREASING NADH OXIDATION

    PubMed Central

    Maalouf, Marwan; Sullivan, Patrick G.; Davis, Laurie; Kim, Do Young; Rho, Jong M.

    2007-01-01

    Dietary protocols that increase serum levels of ketones, such as calorie restriction and the ketogenic diet, offer robust protection against a multitude of acute and chronic neurological diseases. The underlying mechanisms, however, remain unclear. Previous studies have suggested that the ketogenic diet may reduce free radical levels in the brain. Thus, one possibility is that ketones may mediate neuroprotection through antioxidant activity. In the present study, we examined the effects of the ketones β-hydroxybutyrate and acetoacetate on acutely dissociated rat neocortical neurons subjected to glutamate excitotoxicity using cellular electrophysiological and single-cell fluorescence imaging techniques. Further, we explored the effects of ketones on acutely isolated mitochondria exposed to high levels of calcium. A combination of β-hydroxybutyrate and acetoacetate (1 mM each) decreased neuronal death and prevented changes in neuronal membrane properties induced by 10 μM glutamate. Ketones also significantly decreased mitochondrial production of reactive oxygen species and the associated excitotoxic changes by increasing NADH oxidation in the mitochondrial respiratory chain, but did not affect levels of the endogenous antioxidant glutathione. In conclusion, we demonstrate that ketones reduce glutamate-induced free radical formation by increasing the NAD+/NADH ratio and enhancing mitochondrial respiration in neocortical neurons. This mechanism may, in part, contribute to the neuroprotective activity of ketones by restoring normal bioenergetic function in the face of oxidative stress. PMID:17240074

  17. Breath ketone testing: a new biomarker for diagnosis and therapeutic monitoring of diabetic ketosis.

    PubMed

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

    2014-01-01

    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. 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. 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. 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.

  18. 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

  19. Continuous flow synthesis of α-halo ketones: essential building blocks of antiretroviral agents.

    PubMed

    Pinho, Vagner D; Gutmann, Bernhard; Miranda, Leandro S M; de Souza, Rodrigo O M A; Kappe, C Oliver

    2014-02-21

    The development of a continuous flow process for the multistep synthesis of α-halo ketones starting from N-protected amino acids is described. The obtained α-halo ketones are chiral building blocks for the synthesis of HIV protease inhibitors, such as atazanavir and darunavir. The synthesis starts with the formation of a mixed anhydride in a first tubular reactor. The anhydride is subsequently combined with anhydrous diazomethane in a tube-in-tube reactor. The tube-in-tube reactor consists of an inner tube, made from a gas-permeable, hydrophobic material, enclosed in a thick-walled, impermeable outer tube. Diazomethane is generated in the inner tube in an aqueous medium, and anhydrous diazomethane subsequently diffuses through the permeable membrane into the outer chamber. The α-diazo ketone is produced from the mixed anhydride and diazomethane in the outer chamber, and the resulting diazo ketone is finally converted to the halo ketone with anhydrous ethereal hydrogen halide. This method eliminates the need to store, transport, or handle diazomethane and produces α-halo ketone building blocks in a multistep system without racemization in excellent yields. A fully continuous process allowed the synthesis of 1.84 g of α-chloro ketone from the respective N-protected amino acid within ~4.5 h (87% yield).

  20. Synthesis of trifluoromethyl ketones via tandem Claisen condensation and retro-Claisen C-C bond-cleavage reaction.

    PubMed

    Yang, Dongmei; Zhou, Yuhan; Xue, Na; Qu, Jingping

    2013-04-19

    A highly efficient, operationally simple approach to trifluoromethyl ketones has been developed that builds on the use of a tandem process involving Claisen condensation and retro-Claisen C-C bond cleavage reaction. Enolizable alkyl phenyl ketones were found to react readily with ethyl trifuoroacetate under the promotion of NaH to afford trifluoroacetic ester/ketone exchange products, trifluoromethyl ketones, which were quite different from the general Claisen condensation products, β-diketones. This procedure uses readily available starting materials and can be extended to the preparation of perfluoroalkyl ketones in excellent yield.

  1. Ru (III) catalyzed oxidation of aliphatic ketones by N-bromosuccinimide in aqueous acetic acid: a kinetic study.

    PubMed

    Giridhar Reddy, P; Ramesh, K; Shylaja, S; Rajanna, K C; Kandlikar, S

    2012-01-01

    Kinetics of Ru (III) catalyzed oxidation of aliphatic ketones such as acetone, ethyl methyl ketone, diethyl ketone, iso-butylmethyl ketone by N-bromosuccinimide in the presence of Hg(II) acetate have been studied in aqueous acid medium. The order of [N-bromosuccinimide] was found to be zero both in catalyzed as well as uncatalyzed reactions. However, the order of [ketone] changed from unity to a fractional one in the presence of Ru (III). On the basis of kinetic features, the probable mechanisms are discussed and individual rate parameters evaluated.

  2. 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.

  3. Ketone supplementation decreases tumor cell viability and prolongs survival of mice with metastatic cancer.

    PubMed

    Poff, A M; Ari, C; Arnold, P; Seyfried, T N; D'Agostino, D P

    2014-10-01

    Cancer cells express an abnormal metabolism characterized by increased glucose consumption owing to genetic mutations and mitochondrial dysfunction. Previous studies indicate that unlike healthy tissues, cancer cells are unable to effectively use ketone bodies for energy. Furthermore, ketones inhibit the proliferation and viability of cultured tumor cells. As the Warburg effect is especially prominent in metastatic cells, we hypothesized that dietary ketone supplementation would inhibit metastatic cancer progression in vivo. Proliferation and viability were measured in the highly metastatic VM-M3 cells cultured in the presence and absence of β-hydroxybutyrate (βHB). Adult male inbred VM mice were implanted subcutaneously with firefly luciferase-tagged syngeneic VM-M3 cells. Mice were fed a standard diet supplemented with either 1,3-butanediol (BD) or a ketone ester (KE), which are metabolized to the ketone bodies βHB and acetoacetate. Tumor growth was monitored by in vivo bioluminescent imaging. Survival time, tumor growth rate, blood glucose, blood βHB and body weight were measured throughout the survival study. Ketone supplementation decreased proliferation and viability of the VM-M3 cells grown in vitro, even in the presence of high glucose. Dietary ketone supplementation with BD and KE prolonged survival in VM-M3 mice with systemic metastatic cancer by 51 and 69%, respectively (p < 0.05). Ketone administration elicited anticancer effects in vitro and in vivo independent of glucose levels or calorie restriction. The use of supplemental ketone precursors as a cancer treatment should be further investigated in animal models to determine potential for future clinical use.

  4. Ketone supplementation decreases tumor cell viability and prolongs survival of mice with metastatic cancer

    PubMed Central

    Poff, AM; Ari, C; Arnold, P; Seyfried, TN; D’Agostino, DP

    2014-01-01

    Cancer cells express an abnormal metabolism characterized by increased glucose consumption owing to genetic mutations and mitochondrial dysfunction. Previous studies indicate that unlike healthy tissues, cancer cells are unable to effectively use ketone bodies for energy. Furthermore, ketones inhibit the proliferation and viability of cultured tumor cells. As the Warburg effect is especially prominent in metastatic cells, we hypothesized that dietary ketone supplementation would inhibit metastatic cancer progression in vivo. Proliferation and viability were measured in the highly metastatic VM-M3 cells cultured in the presence and absence of β-hydroxybutyrate (βHB). Adult male inbred VM mice were implanted subcutaneously with firefly luciferase-tagged syngeneic VM-M3 cells. Mice were fed a standard diet supplemented with either 1,3-butanediol (BD) or a ketone ester (KE), which are metabolized to the ketone bodies βHB and acetoacetate. Tumor growth was monitored by in vivo bioluminescent imaging. Survival time, tumor growth rate, blood glucose, blood βHB and body weight were measured throughout the survival study. Ketone supplementation decreased proliferation and viability of the VM-M3 cells grown in vitro, even in the presence of high glucose. Dietary ketone supplementation with BD and KE prolonged survival in VM-M3 mice with systemic metastatic cancer by 51 and 69%, respectively (p < 0.05). Ketone administration elicited anticancer effects in vitro and in vivo independent of glucose levels or calorie restriction. The use of supplemental ketone precursors as a cancer treatment should be further investigated in animal models to determine potential for future clinical use. PMID:24615175

  5. Activities of enzymes of fat and ketone-body metabolism and effects of starvation on blood concentrations of glucose and fat fuels in teleost and elasmobranch fish

    PubMed Central

    Zammit, Victor A.; Newsholme, Eric A.

    1979-01-01

    1. Activities of 3-oxo acid CoA-transferase and carnitine palmitoyltransferase together with tri- and di-acylglycerol lipase were present in red and heart muscles of the teleost fish. However, d-3-hydroxybutyrate dehydrogenase activity was not detectable. These results suggest that the heart and red muscles of the teleosts should be able to utilize the fat fuels triacylglycerol, fatty acids or acetoacetate, but not hydroxybutyrate. The muscles from the elasmobranchs differed in that d-3-hydroxybutyrate dehydrogenase and 3-oxo acid CoA-transferase activities were present, but carnitine palmitoyltransferase activity was not detectable. This suggests that ketone bodies are the most important fat fuels in elasmobranchs. 2. The concentrations of acetoacetate, 3-hydroxybutyrate, glycerol, non-esterified fatty acids and triacylglycerols were measured in blood or plasma of several species of fish (teleosts and elasmobranchs) in the fed state. Teleosts have a 10-fold higher concentration of plasma non-esterified fatty acids, but a lower blood concentration of ketone bodies; both acetoacetate and 3-hydroxybutyrate are present in blood of elasmobranchs, whereas 3-hydroxybutyrate is absent from that of the teleosts. 3. The effects of starvation (up to 150 days) on the concentrations of blood metabolites were studied in a teleost (bass) and an elasmobranch (dogfish). In the bass there was a 60% decrease in blood glucose after 100 and 150 days starvation. In dogfish there was a large increase in the concentration of ketone bodies, whereas in bass the concentration of acetoacetate (the only ketone body present) remained low (<0.04mm) throughout the period of starvation. The concentration of plasma non-esterified fatty acids increased in bass, but decreased in dogfish. These changes are consistent with the predictions based on the enzyme-activity data. 4. Starvation did not change the activities of ketone-body-utilizing enzymes or that of phosphoenolpyruvate carboxykinase in heart

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

    DOE PAGES

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

    2016-04-01

    The asymmetric alkylation of acyclic ketones is a longstanding challenge in organic synthesis. Here, are the 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.

  7. Synthesis of α-Halo-α,α-Difluoromethyl Ketones by a Trifluoroacetate Release/Halogenation Protocol

    PubMed Central

    John, Jinu P.; Colby, David A.

    2011-01-01

    Three series of α-halo-α,α-difluoromethyl ketones are prepared from highly α-fluorinated gem-diols by exploiting the facile release of trifluoroacetate, followed by immediate trapping of the liberated α,α-difluoroenolate with an electrophilic chlorine, bromine, or iodine source. The products are typically isolated in good yields, even in the case of sensitive, α-iodo-α,α-difluoromethyl ketones. Also, we demonstrate that an α-iodo-α,α-difluoromethyl ketone will participate in a copper-promoted reaction to forge a new carbon–carbon bond. PMID:21995668

  8. Novel and Efficient Chromium(II)-Mediated Desulfonylation of α-Sulfonyl Ketone.

    PubMed

    Inanaga, Kazato; Fukuyama, Takashi; Kubota, Manabu; Komatsu, Yuki; Chiba, Hiroyuki; Kayano, Akio; Tagami, Katsuya

    2015-06-19

    A novel and efficient method for the Cr(II)-mediated desulfonylation of α-sulfonyl ketone by a Cr-ligand-Mn system has been developed during the course of process research on Halaven (eribulin mesylate). This reaction is dramatically accelerated in the presence of an appropriate bipyridyl-type ligand. This system is applicable to reduction of α-sulfur-substituted ketones. In addition, a Cr-Cp2ZrCl2-Mn catalytic system is also applicable to desulfonylation of α-sulfonyl ketone.

  9. Direct asymmetric amination of α-branched cyclic ketones catalyzed by a chiral phosphoric acid.

    PubMed

    Yang, Xiaoyu; Toste, F Dean

    2015-03-11

    Here we report the direct asymmetric amination of α-substituted cyclic ketones catalyzed by a chiral phosphoric acid, yielding products with a N-containing quaternary stereocenter in high yields and excellent enantioselectivities. Kinetic resolution of the starting ketone was also found to occur on some of the substrates under milder conditions, providing enantioenriched α-branched ketones, another important building block in organic synthesis. The utility of this methodology was demonstrated in the short synthesis of (S)-ketamine, the more active enantiomer of this versatile pharmaceutical.

  10. Direct Asymmetric Amination of α-Branched Cyclic Ketones Catalyzed by a Chiral Phosphoric Acid

    PubMed Central

    Yang, Xiaoyu; Toste, F. Dean

    2015-01-01

    Here we report the direct asymmetric amination of α-substituted cyclic ketones catalyzed by a chiral phosphoric acid, yielding products with a N-containing quaternary stereocenter in high yields and excellent enantioselectivities. Kinetic resolution of the starting ketone was also found to occur on some of the substrates under milder conditions, providing enantio-enriched α-branched ketones, another important building block in organic synthesis. The utility of this methodology was demonstrated in the short synthesis of (S)-ketamine, the more active enantiomer of this versatile pharmaceutical. PMID:25719604

  11. An efficient procedure based on a MW-assisted Horner-Wadsworth-Emmons reaction for the synthesis of (Z)-3,3-trisubstituted-alpha,beta-unsaturated esters.

    PubMed

    Rossi, Daniela; Baraglia, Anna Carnevale; Serra, Massimo; Azzolina, Ornella; Collina, Simona

    2010-08-27

    A microwave-assisted HWE olefination process of readily accessible aryl-alkyl ketones has been developed to provide a rapid access to (Z)-3,3-trisubstituted-alpha,beta-unsaturated methyl esters, key building blocks for the synthesis of biologically active compounds.

  12. Methodology for in situ protection of aldehydes and ketones using trimethylsilyl trifluoromethanesulfonate and phosphines: selective alkylation and reduction of ketones, esters, amides, and nitriles.

    PubMed

    Yahata, Kenzo; Minami, Masaki; Yoshikawa, Yuki; Watanabe, Kei; Fujioka, Hiromichi

    2013-01-01

    A methodology for selective transformations of ketones, esters, Weinreb amides, and nitriles in the presence of aldehydes has been developed. The use of a combination of PPh(3)-trimethylsilyl trifluoromethanesulfonate (TMSOTf) promotes selective transformation of aldehydes to their corresponding, temporarily protected, O,P-acetal type phosphonium salts. Because, hydrolytic work-up following ensuing reactions of other carbonyl moieties in the substrates liberates the aldehyde moiety, a sequence involving aldehyde protection, transformation of other carbonyl groups, and deprotection can be accomplished in a one-pot manner. Furthermore, the use of PEt(3) instead of PPh(3) enables ketones to be converted in situ to their corresponding O,P-ketal type phosphonium salts and, consequently, selective transformations of esters, Weinreb amides, and nitriles in the presence of ketones can be performed. This methodology is applicable to various dicarbonyl compounds, including substrates that possess heteroaromatic skeletons and hydroxyl protecting groups.

  13. A mechanistic analysis of the quantitation of α-hydroxy ketones by the bicinchoninic acid assay.

    PubMed

    Weiser, Jennifer R; Ricapito, Nicole G; Yueh, Alice; Weiser, Ellen L; Putnam, David

    2012-11-15

    A new class of compounds amenable to quantification by the bicinchoninic acid (BCA) assay was identified, allowing an expansion of compounds quantifiable within the assay's capacity. In this article, we demonstrate that compounds containing the α-hydroxy ketone structure are easily measured under standard BCA assay conditions. A nonchromophore analyte containing the α-hydroxy ketone structure, 1,3-dihydroxypropan-2-one (commonly known as dihydroxyacetone), and various structural derivatives were explored on an equimolar basis in the BCA assay. Combined with earlier studies exploring α-hydroxy ketones within copper oxidation systems, the data support the mechanism of this class of compound's ability to enolize through an enediol intermediate to generate a strong signal in the BCA assay. This new quantification technique also highlights the potential for α-hydroxy ketones to interfere with other analytes quantified by the BCA assay.

  14. Lewis base catalyzed, enantioselective aldol addition of methyl trichlorosilyl ketene acetal to ketones.

    PubMed

    Denmark, Scott E; Fan, Yu; Eastgate, Martin D

    2005-06-24

    The catalytic enantioselective addition of an acetate enolate equivalent to ketones is described. Methyl trichlorosilyl ketene acetal reacts with a wide range of ketones in the presence of pyridine N-oxide to afford the aldol addition products in excellent yields. Chiral 2,2'-pyridyl bis-N-oxides bearing various substituents at the 3,3'- and 6,6'-positions also provide excellent yields of the aldol products with variable enantioselectivities ranging from 94/6 er for aromatic ketones to nearly racemic for aliphatic ketones. An X-ray crystal structure of the complex between a catalyst and silicon tetrachloride (((P)-(R,R)-19.SiCl(4))) has been obtained. Extensive computational analysis provides a stereochemical rationale for the observed trends in enantioselectivities.

  15. Radical photocyclization route for macrocyclic lactone ring expansion and conversion to macrocyclic lactams and ketones.

    PubMed

    Nishikawa, Keisuke; Yoshimi, Yasuharu; Maeda, Kousuke; Morita, Toshio; Takahashi, Ichiro; Itou, Tatsuya; Inagaki, Sho; Hatanaka, Minoru

    2013-01-18

    A new method for the synthesis of macrocyclic lactones, lactams, and ketones, which utilizes photoinduced intramolecular radical cyclization reactions of substrates containing tethered carboxylic acids and α,β-unsaturated carbonyl moieties, has been uncovered. Photocyclization of the carboxylic acids tethered acrylate ester, which were prepared starting from the macrocyclic lactones, gave the two-carbon elongated macrocyclic lactones via decarboxylation. Similar photoreactions of carboxylic acid tethered acryl amide or α,β-unsaturated ketone moieties, which were also prepared starting from the macrocyclic lactones, produced macrocyclic lactams or ketones, respectively. The simple approach can be readily applied to the preparation of a variety of macrocyclic lactones, lactams, and ketones with tunable ring sizes.

  16. Whole-cell biotransformation with recombinant cytochrome P450 for the selective oxidation of Grundmann's ketone.

    PubMed

    Hernández-Martín, Alba; von Bühler, Clemens J; Tieves, Florian; Fernández, Susana; Ferrero, Miguel; Urlacher, Vlada B

    2014-10-15

    25-Hydroxy-Grundmann's ketone is a key building block in the chemical synthesis of vitamin D3 and its derivatives through convergent routes. Generally, the chemical synthesis of this compound involves tedious procedures and results in a mixture of several products. Recently, the selective hydroxylation of Grundmann's ketone at position C25 by cytochrome P450 (CYP) 154E1 from Thermobifida fusca YX was described. In this study a recombinant whole-cell biocatalyst was developed and applied for hydroxylation of Grundmann's ketone. Biotransformation was performed by Escherichia coli cells expressing CYP154E1 along with two redox partner systems, Pdx/PdR and YkuN/FdR. The system comprising CYP154E1/Pdx/PdR showed the highest production of 25-hydroxy-Grundmann's ketone and resulted in 1.1mM (300mgL(-1)) product concentration. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Addition of optically pure H-phosphinate to ketones: selectivity, stereochemistry and mechanism.

    PubMed

    Sun, Yong-Ming; Xin, Nana; Xu, Zhong-Yuan; Liu, Li-Juan; Meng, Fan-Jie; Zhang, He; Fu, Bao-Ci; Liang, Qiu-Ju; Zheng, Hong-Xing; Sun, Li-Jun; Zhao, Chang-Qiu; Han, Li-Biao

    2014-12-14

    Aromatic methyl ketones and cyclic asymmetric ketones underwent hydrophosphorylation with P-stereogenic H-P species in the presence of potassium carbonate to produce P,C-stereogenic tertiary α-hydroxyl phosphinates in excellent yields with up to 99 : 1 dr. The diastereoselectivity was induced by a reversible conversion of less stable stereomer of product to that of a more stable one via an equilibrium, which was confirmed by aldehyde/ketone exchanging reaction. Toward the exchange, aliphatic or aldehyde carbonyl were more active than aromatic or ketone carbonyls, respectively. The stability difference between the two diastereomers was controlled by the sizes of substituents linking to phosphorus or α-carbon.

  18. Comparative inhibition of tetrameric carbonyl reductase activity in pig heart cytosol by alkyl 4-pyridyl ketones.

    PubMed

    Shimada, Hideaki; Tanigawa, Takahiro; Matayoshi, Kazunori; Katakura, Kazufumi; Babazono, Ken; Takayama, Hiroyuki; Murahashi, Tsuyoshi; Akita, Hiroyuki; Higuchi, Toshiyuki; Eto, Masashi; Imamura, Yorishige

    2014-06-01

    The present study is to elucidate the comparative inhibition of tetrameric carbonyl reductase (TCBR) activity by alkyl 4-pyridyl ketones, and to characterize its substrate-binding domain. The inhibitory effects of alkyl 4-pyridyl ketones on the stereoselective reduction of 4-benzoylpyridine (4-BP) catalyzed by TCBR were examined in the cytosolic fraction of pig heart. Of alkyl 4-pyridyl ketones, 4-hexanoylpyridine, which has a straight-chain alkyl group of five carbon atoms, inhibited most potently TCBR activity and was a competitive inhibitor. Furthermore, cyclohexyl pentyl ketone, which is substituted by cyclohexyl group instead of phenyl group of hexanophenone, had much lower ability to be reduced than hexanophenone. These results suggest that in addition to a hydrophobic cleft corresponding to a straight-chain alkyl group of five carbon atoms, a hydrophobic pocket with affinity for an aromatic group is located in the substrate-binding domain of TCBR.

  19. Direct reductive amination of aldehydes and ketones using phenylsilane: catalysis by dibutyltin dichloride.

    PubMed

    Apodaca, R; Xiao, W

    2001-05-31

    A procedure for direct reductive amination of aldehydes and ketones was developed which uses phenylsilane as a stoichiometric reductant and dibutyltin dichloride as a catalyst. Suitable amines included anilines and dialkylamines but not monoalkylamines.

  20. Acetylleucine chloromethyl ketone, an inhibitor of acylpeptide hydrolase, induces apoptosis of U937 cells.

    PubMed

    Yamaguchi, M; Kambayashi, D; Toda, J; Sano, T; Toyoshima, S; Hojo, H

    1999-09-16

    Acetylleucine chloromethyl ketone (ALCK), an inhibitor of acylpeptide hydrolase (ACPH), inhibited the growth of human monoblastic U937 cells in a dose- and time-dependent manner. Morphology of the ALCK-exposed cells showed typical apoptosis, judging from the nuclear condensation and segmentation. Chromosomal DNA of U937 cells treated with ALCK showed an internucleosomal ladder-like pattern on electrophoresis, being characteristic of apoptosis. Of the other leucine chloromethyl ketone analogues, butyloylleucine chloromethyl ketone (BLCK) induced a weak ladder-like formation but caploylleucine chloromethyl ketone (CLCK)barely did. On the other hand, intracellular ACPH activity of U937 cells was strongly inhibited by culturing with ALCK, moderately with BLCK, and not with CLCK. These findings indicate that the inhibition of ACPH activity leads to apoptosis and suggest that ACPH may play a vital role in eukaryotic cells. Copyright 1999 Academic Press.

  1. Iodine-catalyzed [Formula: see text] C-H bond activation by selenium dioxide: synthesis of diindolylmethanes and di(3-indolyl)selanides.

    PubMed

    Naidu, P Seetham; Majumder, Swarup; Bhuyan, Pulak J

    2015-11-01

    An efficient reaction protocol was developed for the synthesis of several diindolylmethane derivatives via the [Formula: see text] C-H bond activation of aryl methyl ketones by [Formula: see text] and indoles in the presence of catalytic amounts of [Formula: see text] at 80 [Formula: see text] using dioxane as solvent. Unexpectedly, an interesting class of di(3-indolyl)selenide compounds was isolated when the reaction was carried out at room temperature.

  2. Synthesis of beta-tetrazolyl DL-alanine derivatives.

    PubMed

    Alami, A; el Hallaoui, A; Elachqar, A; el Hajji, S; Roumestant, M L; Viallefont, P

    1998-05-01

    Interest in non-natural alpha-amino acids is growing because of their potential biological activity. We describe, in this paper, a synthesis of beta-tetrazolyl alpha-amino esters by action of 5-aryl tetrazoles, 2, on N-benzyloxycarbonyl di-dehydro methylalaninate, 3.

  3. Ultrasound mediation for efficient synthesis of monoarylidene derivatives of homo- and heterocyclic ketones.

    PubMed

    Mojtahedi, Mohammad M; Abaee, M Saeed; Samianifard, Mehdieh; Shamloo, Akram; Padyab, Masoomeh; Mesbah, A Wahid; Harms, Klaus

    2013-05-01

    Ultrasonic irradiation was efficiently used for high yield synthesis of monoarylidene derivatives of cyclic systems directly from the reaction of ketone with various aldehydes under solvent-free conditions. Reactions took place rapidly in the presence of catalytic amounts of pyrrolidine, while no significant formation of the undesired bis by-products was observed. Moreover, the procedure was applicable to both homo- and heterocyclic ketones. Copyright © 2012 Elsevier B.V. All rights reserved.

  4. Preparation of unsymmetrical ketones from tosylhydrazones and aromatic aldehydes via formyl C-H bond insertion.

    PubMed

    Allwood, Daniel M; Blakemore, David C; Ley, Steven V

    2014-06-06

    Preparation of ketones by insertion of diazo compounds into the formyl C-H bond of an aldehyde is an attractive procedure, but use of structurally diverse diazo compounds is hampered by preparation and safety issues. A convenient procedure for the synthesis of unsymmetrical ketones from bench-stable tosylhydrazones and aryl aldehydes is reported. The procedure can be performed in one pot from the parent carbonyl compound and needs only a base, with no additional promoters being required.

  5. Direct conversion of alcohols to α-chloro aldehydes and α-chloro ketones.

    PubMed

    Jing, Yuanyuan; Daniliuc, Constantin G; Studer, Armido

    2014-09-19

    Direct conversion of primary and secondary alcohols into the corresponding α-chloro aldehydes and α-chloro ketones using trichloroisocyanuric acid, serving both as stoichiometric oxidant and α-halogenating reagent, is reported. For primary alcohols, TEMPO has to be added as an oxidation catalyst, and for the transformation of secondary alcohols (TEMPO-free protocol), MeOH as an additive is essential to promote chlorination of the intermediary ketones.

  6. Sources and concentrations of aldehydes and ketones in indoor environments in the UK

    SciTech Connect

    Crump, D.R.; Gardiner, D. )

    1989-01-01

    Individual aldehydes and ketones can be separated, identified and quantitatively estimated by trapping the 2,4-dinitrophenylhydrazine (DNPH) derivatives and analysis by HPLC. Appropriate methods and detection limits are reported. Many sources of formaldehyde have been identified by this means and some are found to emit other aldehydes and ketones. The application of this method to determine the concentration of these compounds in the atmospheres of buildings is described and the results compared with those obtained using chromotropic acid or MBTH.

  7. Enantioselective Synthesis of β-(3-Hydroxypyrazol-1-yl)ketones Using An Organocatalyzed Michael Addition Reaction

    PubMed Central

    Gogoi, Sanjib; Zhao, Cong-Gui; Ding, Derong

    2009-01-01

    β-(3-Hydroxypyrazol-1-yl)ketones have been prepared in high yields and excellent enantioselectivities (94–98% ee) via a Michael addition reaction between 2-pyrazolin-5-ones and aliphatic acyclic α,β-unsaturated ketones using 9-epi-9-amino-9-deoxyquinine as the catalyst. These results account for the first example of an aza-Michael addition of the ambident 2-pyrazolin-5-one anion to a Michael acceptor. PMID:19415906

  8. Extent of charge transfer in the photoreduction of phenyl ketones by alkylbenzenes

    SciTech Connect

    Wagner, P.J.; Truman, R.J.; Puchalski, A.E.; Wake, R.

    1986-11-26

    Rate constants for triplet-state reaction of various ring-substituted benzophenones (BPs), acetophenones (APs), and ..cap alpha..,..cap alpha..,..cap alpha..-trifluoroacetophenones (TFAs) with toluene and p-xylene have been determined by a combination of flash kinetics, steady-state quenching, and quantum yield measurements. The relative amounts of primary and tertiary radicals formed by reaction of the same ketones with p-cymene have also been measured. For all three types of ketones, rate constants correlate well with triplet ketone reduction potentials. The magnitude of the kinetic isotope effects observed with toluene-d/sub 8/ and p-xylene-d/sub 10/ diminishes as the ketones become easier to reduce. All of the ketone triplets react with alkylbenzenes primarily by a charge-transfer mechanism, with the rate-determining step changing from complexation to hydrogen transfer as the ketones become harder to reduce. The least reactive AP triplets probably react significantly via simple hydrogen atom abstraction as well. Those ketones with n,..pi..* lowest triplets (all BPs and some APs) react with p-cymene to give primary/tertiary radical ratios that vary no more than a factor of 2 from the 0.40 value displayed by tert-butoxy radicals; those with ..pi..,..pi..* lowest triplets (TFAs and some APs) give ratios that favor primary radicals and that vary by an order of magnitude with the triplet ketone reduction potential. The variation in cymene product ratios reflects different orientations for attack on cymene by n,..pi..* and ..pi..,..pi..* triplets and differing degrees of partial electron transfer within the exciplexes, which are not tight radical ion pairs.

  9. Synthesis and evaluation of phenylalanine-derived trifluoromethyl ketones for peptide-based oxidation catalysis.

    PubMed

    Featherston, Aaron L; Miller, Scott J

    2016-10-15

    We report the synthesis of phenylalanine-derived trifluoromethyl ketones for the in situ generation of dioxiranes for the purpose of oxidation catalysis. The key features of this synthesis include the use of a masked ketone strategy and a Negishi cross-coupling to access the parent amino acid. The derivatives can be readily incorporated into a peptide for use in oxidation chemistry and exhibit good stability and reactivity. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Tyrosine-derived 4-hydroxyphenylpyruvate reacts with ketone test fields of 3 commercially available urine dipsticks.

    PubMed

    Cartwright, James; Green, Richard M

    2010-09-01

    The enzyme 4-hydroxyphenylpyruvate dioxygenase (HPPD) is key in tyrosine catabolism. Inhibition of HPPD results in tyrosinemia and increased urinary excretion of 3 phenylketones: 4-hydroxyphenylpyruvate (HPPA), 4-hydroxyphenyllactate (HPLA), and 4-hydroxyphenylacetate (HPAA). A previous study involving administration of a novel HPPD inhibitor to dogs resulted in detection of ketonuria in treated animals using urine dipsticks read by reflectance photometry. Dipstick-positive results were suspected to be false because high concentrations of urinary phenylketones have been reported to react with ketone test fields of urine dipsticks, but visual confirmation was not performed. The purpose of this study was to determine which of the 4- hydroxyphenolic acids produced by HPPD inhibition react with ketone test fields of 3 commercially available urine dipsticks. Canine urine samples were prepared with HPPA, HPLA, HPAA, and lithium acetoacetate (positive control) at 6 concentrations. Unmodified urine samples were used as negative controls. All samples were tested for ketones using Combur 10 Test M dipsticks read by a Miditron dipstick analyzer. Urinalysis was also performed by visually inspecting ketone test fields on the Combur 10 Test M, Multistix 10 SG, and Aution 10 EA dipsticks. Urine samples containing HPPA were positive for ketones with Combur 10 Test M dipsticks read by the Miditron analyzer and produced a red–brown color change in ketone test fields of all 3 dipsticks. Urine samples containing HPLA and HPAA were negative by all methods. The phenylketone HPPA reacts with ketone test fields of 3 commercially available urine dipsticks, producing a red–brown color change that may be misinterpreted as positive for ketones by reflectance photometry.

  11. 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

  12. Domino hydroformylation/aldol condensation/hydrogenation catalysis: highly selective synthesis of ketones from olefins.

    PubMed

    Fang, Xianjie; Jackstell, Ralf; Börner, Armin; Beller, Matthias

    2014-11-24

    A general and highly chemo- and regioselective synthesis of ketones from olefins by domino hydroformylation/aldol condensation/hydrogenation reaction has been developed. A variety of olefins are efficiently converted into various ketones in good to excellent yields and regioselectivities in the presence of a specific rhodium phosphine/base-acid catalyst system. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Unexpected metal-free transformation of gem-Dibromomethylenes to ketones under acetylation conditions.

    PubMed

    Kimura, Rino; Sawayama, Yusuke; Nakazaki, Atsuo; Miyamoto, Kazunori; Uchiyama, Masanobu; Nishikawa, Toshio

    2015-04-01

    Novel conditions for the transformation of gem-dibromomethylenes to ketones are described. gem-Dibromo compounds were treated with acetic anhydride and triethylamine in dichloromethane/water at room temperature under an air atmosphere to give the corresponding ketones in moderate yields. A radical mechanism is proposed based on experimental results. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Reductive cyclizations of hydroxysulfinyl ketones: enantioselective access to tetrahydropyran and tetrahydrofuran derivatives.

    PubMed

    Carreño, M Carmen; Des Mazery, Renaud; Urbano, Antonio; Colobert, Françoise; Solladié, Guy

    2003-10-03

    The stereocontrolled formation of cis-2,5-disubstituted tetrahydrofurans and cis-2,6-disubstituted tetrahydropyrans is achieved from enantiopure ketosulfinyl esters by reduction, Weinreb's amide, and ketone formation, followed by the reductive cyclization (Et3SiH/TMSOTf) of the resulting hydroxysulfinyl ketones. The sulfoxide-bearing heterocycles were transformed into two natural products, (-)-centrolobine (1) and both enantiomers of cis-(6-methyltetrahydropyran-2-yl)acetic acid (2).

  15. Catalytic transformation of esters of 1,2-azido alcohols into α-amido ketones.

    PubMed

    Kim, Yongjin; Pak, Han Kyu; Rhee, Young Ho; Park, Jaiwook

    2016-05-05

    The esters of 1,2-azido alcohols were transformed into α-amido ketones without external oxidants through the Ru-catalyzed formation of N-H imines with the liberation of N2 followed by intramolecular migration of the acyl moiety. A wide range of α-amido ketones were obtained, and one-pot transformation into the corresponding oxazoles (or a thiazole) was demonstrated.

  16. 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

    2015-12-07

    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. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Mass spectral determination of aldehydes, ketones, and carboxylic acids using 1,1-dimethylhydrazine.

    PubMed

    McDaniel, C A; Howard, R W

    1985-03-01

    Analyses of nanogram to milligram quantities of aliphatic aldehydes, fatty acids, and unhindered aliphatic ketones such as those typically found in pheromonal blends have been effected by treating these mixtures with 1,1-dimethylhydrazine. The aldehydes and ketones formN,N-dimethylhydrazones, while the fatty acids form methyl esters. Structural elucidation of the reaction products was achieved using EI and CI gas chromatography-mass spectrometry.

  18. Ketone-imide versus ketone-oxime reductive cross-coupling promoted by samarium diiodide: new mechanistic insight gained from a failed aminocyclopentitol synthesis.

    PubMed

    Chiara, Jose Luis; García, Angela; Cristóbal-Lumbroso, Gabriella

    2005-05-13

    [reaction: see text] The intramolecular 1,6-ketone/imide reductive coupling promoted by samarium diiodide competes favorably with an alternative 1,5-ketone/oxime ether coupling in a keto-oxime substrate derived from D-glucosamine N-protected with a phthalimido group. This pinacol coupling reaction affords new homochiral alpha-hydroxylactam scaffolds that could be useful in diversity-oriented synthesis. A mechanistic proposal for this reaction that explains the experimental results is supported by DFT quantum-mechanical calculations on model compounds.

  19. 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

  20. Study of the antibacterial and antifungal activities of synthetic benzyl bromides, ketones, and corresponding chalcone derivatives.

    PubMed

    Shakhatreh, Muhamad Ali K; Al-Smadi, Mousa L; Khabour, Omar F; Shuaibu, Fatima A; Hussein, Emad I; Alzoubi, Karem H

    2016-01-01

    Several applications of chalcones and their derivatives encouraged researchers to increase their synthesis as an alternative for the treatment of pathogenic bacterial and fungal infections. In the present study, chalcone derivatives were synthesized through cross aldol condensation reaction between 4-(N,N-dimethylamino)benzaldehyde and multiarm aromatic ketones. The multiarm aromatic ketones were synthesized through nucleophilic substitution reaction between 4-hydroxy acetophenone and benzyl bromides. The benzyl bromides, multiarm aromatic ketones, and corresponding chalcone derivatives were evaluated for their activities against eleven clinical pathogenic Gram-positive, Gram-negative bacteria, and three pathogenic fungi by the disk diffusion method. The minimum inhibitory concentration was determined by the microbroth dilution technique. The results of the present study demonstrated that benzyl bromide derivatives have strong antibacterial and antifungal properties as compared to synthetic chalcone derivatives and ketones. Benzyl bromides (1a and 1c) showed high ester activity against Gram-positive bacteria and fungi but moderate activity against Gram-negative bacteria. Therefore, these compounds may be considered as good antibacterial and antifungal drug discovery. However, substituted ketones (2a-b) as well as chalcone derivatives (3a-c) showed no activity against all the tested strains except for ketone (2c), which showed moderate activity against Candida albicans.

  1. 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.

  2. Study of the antibacterial and antifungal activities of synthetic benzyl bromides, ketones, and corresponding chalcone derivatives

    PubMed Central

    Shakhatreh, Muhamad Ali K; Al-Smadi, Mousa L; Khabour, Omar F; Shuaibu, Fatima A; Hussein, Emad I; Alzoubi, Karem H

    2016-01-01

    Several applications of chalcones and their derivatives encouraged researchers to increase their synthesis as an alternative for the treatment of pathogenic bacterial and fungal infections. In the present study, chalcone derivatives were synthesized through cross aldol condensation reaction between 4-(N,N-dimethylamino)benzaldehyde and multiarm aromatic ketones. The multiarm aromatic ketones were synthesized through nucleophilic substitution reaction between 4-hydroxy acetophenone and benzyl bromides. The benzyl bromides, multiarm aromatic ketones, and corresponding chalcone derivatives were evaluated for their activities against eleven clinical pathogenic Gram-positive, Gram-negative bacteria, and three pathogenic fungi by the disk diffusion method. The minimum inhibitory concentration was determined by the microbroth dilution technique. The results of the present study demonstrated that benzyl bromide derivatives have strong antibacterial and antifungal properties as compared to synthetic chalcone derivatives and ketones. Benzyl bromides (1a and 1c) showed high ester activity against Gram-positive bacteria and fungi but moderate activity against Gram-negative bacteria. Therefore, these compounds may be considered as good antibacterial and antifungal drug discovery. However, substituted ketones (2a–b) as well as chalcone derivatives (3a–c) showed no activity against all the tested strains except for ketone (2c), which showed moderate activity against Candida albicans. PMID:27877017

  3. Temporal changes in plasma levels and metabolism of ketone bodies by liver and brain after ethanol and/or starvation in C57BL/6J mice.

    PubMed

    Schreiber, R A; Yeh, Y Y

    1984-03-01

    The effects of ethanol and starvation on ketone body production and utilization were investigated. In the first experiment, adult C57BL/6J mice were divided into four groups: (i) control (fed); (ii) starvation (up to 31 h); (iii) ethanol (acute 5 g/kg i.p.); (iv) ethanol (ETOH) + starvation. Plasma ketone body (KB) concentrations in control mice remained constant at approx. 0.37 mM. The levels of KBs in starved mice began to increase at about 7 h and rose to a peak of 2.5 mM at about 24 h, then fell to 1.8 mM at 31 h. The levels in mice treated with ETOH began to rise soon after injection, reached 1.5 mM at 10 h, and returned to control levels by 15 h. Although there was no difference in elevated levels of KBs between two groups of mice treated with ETOH plus starvation and ETOH alone at 7-10 h, the level continued to rise steadily to 2.0 mM through 31 h in the former group. At 10 h post ETOH, mice either fed ad lib. or fasted had increased hepatic capacity to synthesize acetoacetate (AcAc) from palmitate; this effect was prolonged and enhanced by continued fasting for 24 h. In the brain, the rate of AcAc oxidation was twice that for beta-hydroxybutyrate (beta OHB) and glucose. Neither ETOH nor starvation affected energy production from KB and glucose. AcAc was also utilized for fatty acid synthesis and the rate of synthesis was stimulated by ETOH at 10 h after injection. The rate of lipogenesis from beta OHB accounted for less than 10% of that from AcAc. Together these experiments demonstrate that ETOH increases both hepatic ketone production and plasma KB levels for at least 10 h. ETOH alone led to elevated KB levels long before the rise due to starvation. In brain, at 10 h, an increased capacity to utilize AcAc for lipogenesis was found. The results indicate that ETOH through the production of KBs could provide an important source of energy and lipid precursors for the brain of mice.

  4. Determination of acetone and methyl ethyl ketone in water

    USGS Publications Warehouse

    Tai, D.Y.

    1978-01-01

    Analytical procedures for the determination of acetone and methyl ethyl ketone in water samples were developed. Concentrations in the milligram-per-liter range were determined by injecting an aqueous sample into the analysis system through an injection port, trapping the organics on Tenax-GC at room temperature, and thermally desorbing the organics into a gas chromatograph with a flame ionization detector for analysis. Concentrations in the microgram-per-liter range were determined by sweeping the headspace vapors over a water sample at 50C, trapping on Tenax-GC, and thermally desorbing the organics into the gas chromatograph. The precision for two operators of the milligram-per-liter concentration procedure, expressed as the coefficient of variation, was generally less than 2 percent for concentrations ranging from 16 to 160 milligrams per liter. The precision from two operators of the microgram-per-liter concentration procedure was between 2 and 4 percent for concentrations of 20 and 60 micrograms per liter. (Woodard-USGS)

  5. Catalytic copolymerization of co/olefin with ketone additive

    SciTech Connect

    Drent, E.

    1989-03-07

    The process of producing a linear alternating polymer of carbon dioxide and at least one ethylenically unsaturated hydrocarbon of 2 to 20 carbon atoms inclusive is described. It consists of contacting carbon monoxide and the hydrocarbon under polymerization conditions in the presence of a catalyst composition prepared from a palladium compound, a non-transition metal salt of a non-hydrohalogenic acid having a pKa less than about 6, a bidentate phosphorus ligand of the formula R/sup 1/R/sup 2/--P--R--P--R/sup 3/R/sup 4/ in which R/sup 1/,R/sup 2/,R/sup 3/ and R/sup 4/ independently are organic radicals of from 1 to 14 carbon atoms inclusive and R is a divalent bridging group of up to 20 carbon atoms and up to 3 carbon atoms in the bridge, and a ketone of from 3 to 20 carbon atoms inclusive and recovering from the resulting product mixture the linear alternating polymer of carbon monoxide and the hydrocarbon.

  6. Detection of Active Matriptase Using a Biotinylated Chloromethyl Ketone Peptide

    PubMed Central

    Godiksen, Sine; Soendergaard, Christoffer; Friis, Stine; Jensen, Jan K.; Bornholdt, Jette; Sales, Katiuchia Uzzun; Huang, Mingdong; Bugge, Thomas H.; Vogel, Lotte K.

    2013-01-01

    Matriptase is a member of the family of type II transmembrane serine proteases that is essential for development and maintenance of several epithelial tissues. Matriptase is synthesized as a single-chain zymogen precursor that is processed into a two-chain disulfide-linked form dependent on its own catalytic activity leading to the hypothesis that matriptase functions at the pinnacle of several protease induced signal cascades. Matriptase is usually found in either its zymogen form or in a complex with its cognate inhibitor hepatocyte growth factor activator inhibitor 1 (HAI-1), whereas the active non-inhibited form has been difficult to detect. In this study, we have developed an assay to detect enzymatically active non-inhibitor-complexed matriptase by using a biotinylated peptide substrate-based chloromethyl ketone (CMK) inhibitor. Covalently CMK peptide-bound matriptase is detected by streptavidin pull-down and subsequent analysis by Western blotting. This study presents a novel assay for detection of enzymatically active matriptase in living human and murine cells. The assay can be applied to a variety of cell systems and species. PMID:24204759

  7. Measurements Alcohols, Ketones, and Aldehydes During Trace-P

    NASA Astrophysics Data System (ADS)

    Apel, E. C.; Riemer, D. D.; Hills, A.; Lueb, R.; Fried, A.; Sachse, G.; Crawford, J.; Singh, H.; Blake, D.

    2002-12-01

    A sensitive and selective instrument (fast gas chromatographic mass spectrometer - FGCMS) was developed for the continuous measurement of oxygenated volatile organic compounds (OVOCs: alcohols, ketones and aldehydes (except for formaldehyde)) containing fewer than 6 carbon atoms and subsequently deployed during the NASA's TRACE-P (Transport and Chemical Evolution over the Pacific) experiment. This paper will briefly describe the instrument and present results obtained from 15 mission flights. Dramatic differences were observed in the mixing ratios and vertical profiles of the longer-lived species, acetone and methanol, compared to the shorter-lived species. For example, between 6 and 7 km, the median mixing ratios for the two longest lived species measured, acetone and methanol, are 765 pptv and 1061 pptv, respectively whereas the combined mixing ratio for all other species measured was less than 500 pptv. A large variety of air masses were encountered during this experiment and this is reflected in the behavior of the measured OVOCs. Relationships between the OVOCs and other trace species will be explored. Implications of these measurements for our current understanding of global tropospheric chemistry will be discussed.

  8. Cereal beta-glucans

    USDA-ARS?s Scientific Manuscript database

    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...

  9. Activation of liver carnitine palmitoyltransferase-1 and mitochondrial acetoacetyl-CoA thiolase is associated with elevated ketone body levels in the elasmobranch Squalus acanthias.

    PubMed

    Treberg, Jason R; Crockett, Elizabeth L; Driedzic, William R

    2006-01-01

    Elasmobranch fishes are an ancient group of vertebrates that have unusual lipid metabolism whereby storage lipids are mobilized from the liver for peripheral oxidation largely as ketone bodies rather than as nonesterified fatty acids under normal conditions. This reliance on ketones, even when feeding, implies that elasmobranchs are chronically ketogenic. Compared to specimens sampled within 2 d of capture (recently captured), spiny dogfish Squalus acanthias that were held for 16-33 d without apparent feeding displayed a 4.5-fold increase in plasma concentration of d- beta -hydroxybutyrate (from 0.71 to 3.2 mM) and were considered ketotic. Overt activity of carnitine palmitoyltransferase-1 in liver mitochondria from ketotic dogfish was characterized by an increased apparent maximal activity, a trend of increasing affinity (reduced apparent K(m); P=0.09) for l-carnitine, and desensitization to the inhibitor malonyl-CoA relative to recently captured animals. Acetoacetyl-CoA thiolase (ACoAT) activity in isolated liver mitochondria was also markedly increased in the ketotic dogfish compared to recently captured fish, whereas no difference in 3-hydroxy-3-methylglutaryl-CoA synthase activity was found between these groups, suggesting that ACoAT plays a more important role in the activation of ketogenesis in spiny dogfish than in mammals and birds.

  10. Availability of neurotransmitter glutamate is diminished when beta-hydroxybutyrate replaces glucose in cultured neurons.

    PubMed

    Lund, Trine M; Risa, Oystein; Sonnewald, Ursula; Schousboe, Arne; Waagepetersen, Helle S

    2009-07-01

    Ketone bodies serve as alternative energy substrates for the brain in cases of low glucose availability such as during starvation or in patients treated with a ketogenic diet. The ketone bodies are metabolized via a distinct pathway confined to the mitochondria. We have compared metabolism of [2,4-(13)C]beta-hydroxybutyrate to that of [1,6-(13)C]glucose in cultured glutamatergic neurons and investigated the effect of neuronal activity focusing on the aspartate-glutamate homeostasis, an essential component of the excitatory activity in the brain. The amount of (13)C incorporation and cellular content was lower for glutamate and higher for aspartate in the presence of [2,4-(13)C]beta-hydroxybutyrate as opposed to [1,6-(13)C]glucose. Our results suggest that the change in aspartate-glutamate homeostasis is due to a decreased availability of NADH for cytosolic malate dehydrogenase and thus reduced malate-aspartate shuttle activity in neurons using beta-hydroxybutyrate. In the presence of glucose, the glutamate content decreased significantly upon activation of neurotransmitter release, whereas in the presence of only beta-hydroxybutyrate, no decrease in the glutamate content was observed. Thus, the fraction of the glutamate pool available for transmitter release was diminished when metabolizing beta-hydroxybutyrate, which is in line with the hypothesis of formation of transmitter glutamate via an obligatory involvement of the malate-aspartate shuttle.

  11. In vitro biosynthesis of 17 alpha,20 alpha,20 beta-dihydroxy-4-pegnen-3-one by the ovaries, testes, and head kidneys of the Atlantic salmon Salmo salar

    SciTech Connect

    Sangalang, G.B.; Freeman, H.C.

    1988-03-01

    Ovaries, testes, and head kidneys of sexually mature Atlantic salmon, Salmo salar, biosynthesized 17 alpha,20 beta-dihydroxy-4-pregnen-3-one (17 alpha,20 beta-diOHP) from equimolar amounts of (/sup 3/H)pregnenolone plus (4-/sup 14/C)progesterone in vitro. The /sup 3/H:/sup 14/C isotope ratios of steroid metabolites indicated that the biosynthetic pathways to 17 alpha,20 beta-diOHP in the testes differed from those observed in the ovaries and head kidneys. (4-/sup 14/C)progesterone appeared to be the principal precursor of 17 alpha,20 beta-diOHP in the testes, whereas both precursors were efficiently biotransformed to 17 alpha,20 beta-diOPH in the ovaries and head kidneys. 17 alpha-Hydroxy-4-pregnen-3-one (17 alpha-OHP) was the immediate precursor to 17 alpha,20 beta-diOHP in all tissues. However, appreciable amounts of 17 alpha,20 beta-diOHP accumulated in vitro in the testes only in the presence of exogenous (/sup 14/C)progesterone. Incubation of the testes, ovaries, and head kidneys with (/sup 14/C)pregnenolone resulted in high yields of 17 alpha,20 beta-diOHP in the ovaries and head kidneys but no detectable amounts of the steroid in the testes. The results confirm that progesterone is the favored precursor to 17 alpha,20 beta-diOHP in the testes. The results also suggest that the head kidneys may be an excellent cellular source of 17 alpha,20 beta-diOHP in both male and female. Atlantic salmon and may play an important role in the sexual maturation process in this fish. It is suggested that biosynthetic control mechanism affecting 17 alpha,20 beta-diOHP synthesis and/or spermiation and ovulation may differ in male and female Atlantic salmon.

  12. Tagging the Untaggable: A Difluoroalkyl-Sulfinate Ketone-Based Reagent for Direct C-H Functionalization of Bioactive Heteroarenes.

    PubMed

    Gnaim, Samer; Scomparin, Anna; Li, Xiuling; Baran, Phil S; Rader, Christoph; Satchi-Fainaro, Ronit; Shabat, Doron

    2016-09-21

    We have developed a new difluoroalkyl ketal sulfinate salt reagent suitable for direct derivatization of heteroarene C-H bonds. The reagent is capable of introducing a ketone functional group on heteroarene bioactive compounds via a one-pot reaction. Remarkably, in three examples the ketone analog and its parent drug had almost identical cytotoxicity. In a representative example, the ketone analog was bioconjugated with a delivery vehicle via an acid-labile semicarbazone linkage and with a photolabile protecting group to produce the corresponding prodrug. Controlled release of the drug-ketone analog was demonstrated in vitro for both systems. This study provides a general approach to obtain taggable ketone analogs directly from bioactive heteroarene compounds with limited options for conjugation. We anticipate that this sodium ketal-sulfinate reagent will be useful for derivatization of other heteroarene-based drugs to obtain ketone-taggable analogs with retained efficacy.

  13. Tautomer-selective derivatives of enolate, ketone and enaminone by addition reaction of picolyl-type anions with nitriles

    NASA Astrophysics Data System (ADS)

    Bai, Jianliang; Wang, Peng; Cao, Wei; Chen, Xia

    2017-01-01

    We describe an efficient for the synthesis of compounds of tautomeric β-pyridyl/quinolyl-enol, -ketone, -enaminone, which were finally characterized by standard methods like NMR, IR or SCXRD. The addition reaction of lithiated intermediates of picoline, 2-ethylpyridine and 2-methylquinoline, respectively, with nitriles followed by acid hydrolysis afforded the corresponding tautomeric compounds of enol, ketone and emaminone. Interestingly, treatment of 2-methylpyridine or 2-ethylpyridine with nitriles, respectively, yielded mostly β-pyridyl ketone and enol tautomers without enaminones, while 2-methylquinoline with nitriles gave β-quinolyl ketone and enaminone tautomers without enols. The reaction of 2-benzylpyridine with nitriles was not available under the same conditions.

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

    DOE PAGES

    Bai, Da -Chang; Yu, Fei -Le; Wang, Wan -Ying; ...

    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

  15. 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.

  16. 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.

  17. [Determination of methyl propyl ketone in air of workplace by capillary gas chromatography].

    PubMed

    Zhang, Jian; Zhang, Wanchao; Zhao, Shulan

    2014-10-01

    To establish a gas chromatography method for determination of methyl propyl ketone in the air of workplace. Methyl propyl ketone in the air of workplace was collected with activated carbon tubes and desorbed with carbon disulfide before sample loading. The target toxicant was separated with the capillary column and detected with a hydrogen flame ionization detector, identified by retention time, and quantified by peak area. The linear range of methyl propyl ketone in the air of workplace was 202.5∼4 860.0 µg/ml, with a correlation coefficient of 0.999 98. The limit of detection was 1.5 µg/ml. The lower limit of quantification was 5.0 µg/ml. The minimum detectable concentration was 1.0 mg/m(3) under 1.5 L sampling volume and 1.0 ml desorption solution volume. The relative standard deviation of different methyl propyl ketone concentrations was 1.42%∼1.65%, and the recovery rate was 94.9%∼ 97.9%. This method has high sensitivity, precision, and accuracy, and it is applicable for determination of methyl propyl ketone in the air of workplace.

  18. Tuning gelation time and morphology of injectable hydrogels using ketone-hydrazide cross-linking.

    PubMed

    Patenaude, Mathew; Campbell, Scott; Kinio, Dennis; Hoare, Todd

    2014-03-10

    Injectable, covalently in situ forming hydrogels based on poly(N-isopropylacrylamide) have been designed on the basis of mixing hydrazide-functionalized nucleophilic precursor polymers with electrophilic precursor polymers functionalized with a combination of ketone (slow reacting) and aldehyde (fast reacting) functional groups. By tuning the ratio of aldehyde:ketone functional groups as well as the total number of ketone groups in the electrophilic precursor polymer, largely independent control over hydrogel properties including gelation time (from seconds to hours), degradation kinetics (from hours to months), optical transmission (from 1 to 85%), and mechanics (over nearly 1 order of magnitude) can be achieved. In addition, ketone-functionalized precursor polymers exhibit improved cytocompatibility at even extremely high concentrations relative to polymers functionalized with aldehyde groups, even at 4-fold higher functional group densities. Overall, increasing the ketone content of the precursor copolymers can result in in situ-gellable hydrogels with improved transparency and biocompatibility and equivalent mechanics and stimuli-responsiveness while only modestly sacrificing the speed of gel formation.

  19. [Investigation on emission characteristics of methanol vehicle's aldehyde and ketone pollutants].

    PubMed

    Tan, Jian-wei; Ge, Yun-shan; Wang, Jun-fang; Liu, Zhi-hua; Han, Xiu-kun; Wang, Meng

    2009-08-15

    Investigation on the character and quantity of aldehydes and ketones emitted from methanol vehicle was implemented respectively by using high performance liquid chromatograph (HPLC) method. Experiments of vehicles equipped with and without three-way catalyst (TWC) under transient and steady mode were carried out. The emission results were compared with that of gasoline vehicle. The data showed that the efficiency of aldehydes and ketones emitted from methanol vehicle and gasoline vehicle were 22.53% and 48.95% with TWC under transient state respectively. When the vehicle is fueled with methanol, the main emissions are formaldehyde, acetaldehyde, acraldehyde + acetone, and these three matters account for 97.18% of the total emission. This proportion is 39.07% when the vehicle is fueled with gasoline. However, the total quantity of aldehydes and ketones from methanol vehicle without TWC was less than that from gasoline vehicle without TWC. Whether with or without TWC, aldehydes and ketones from methanol vehicle were more than that from gasoline vehicle under steady states. When the vehicle is fueled with methanol, the emission of aldehydes and ketones is on the top level at the speed of 60 km/h, and the converting efficiency is also the highest, which is 88.50%. When at the speed of 60 km/h, 90 km/h, 120 km/h, the formaldehyde quantity of methanol vehicle was 332.94%, 374.47% and 357.58% as much as that from gasoline vehicle respectively.

  20. The promising potential role of ketones in inflammatory dermatologic disease: a new frontier in treatment research.

    PubMed

    Fomin, Daren A; McDaniel, Brianna; Crane, Jonathan

    2017-01-24

    The ketogenic diet has been shown to be beneficial for numerous diseases across different organ systems, but a dearth of information exists regarding these benefits for skin disease. Here, we searched the literature for known mechanisms behind inflammation in dermatologic disease and correlated that with suggested mechanisms of anti-inflammatory activity of ketones and a ketogenic state in the human body to observe how ketones and ketosis might aid in the treatment of inflammatory skin diseases based on these mechanisms. Specifically, we found that ketones modulate the NRPL3 inflammasome, augment anti-oxidation against reactive oxygen species through various direct and indirect means, and may influence mTOR activity, which are all involved in inflammatory dermatologic diseases to an extent. This evidence shows that ketones and the ketogenic diet may have a promising role in the dermatologist's disease treatment repertoire. Our goal is to provide a novel direction for research in the role of a ketogenic diet and even exogenous ketone therapy in the treatment of inflammatory dermatologic disease.

  1. Uptake of aldehydes and ketones at typical indoor concentrations by houseplants.

    PubMed

    Tani, Akira; Hewitt, C Nicholas

    2009-11-01

    The uptake rates of low-molecular weight aldehydes and ketones by peace lily (Spathiphyllum clevelandii) and golden pothos (Epipremnum aureum) leaves at typical indoor ambient concentrations (10(1)-10(2) ppbv) were determined. The C3-C6 aldehydes and C4-C6 ketones were taken up by the plant leaves, but the C3 ketone acetone was not. The uptake rate normalized to the ambient concentration C(a) ranged from 7 to 19 mmol m(-2) s(-1) and from 2 to 7 mmol m(-2) s(-1) for the aldehydes and ketones, respectively. Longer-term fumigation results revealed that the total uptake amounts were 30-100 times as much as the amounts dissolved in the leaf, suggesting that volatile organic carbons are metabolized in the leaf and/or translocated through the petiole. The ratio of the intercellular concentration to the external (ambient) concentration (C(i)/C(a)) was significantly lower for most aldehydes than for most ketones. In particular, a linear unsaturated aldehyde, crotonaldehyde, had a C(i)/C(a) ratio of approximately 0, probably because of its highest solubility in water.

  2. Nile red detection of bacterial hydrocarbons and ketones in a high-throughput format.

    PubMed

    Pinzon, Neissa M; Aukema, Kelly G; Gralnick, Jeffrey A; Wackett, Lawrence P

    2011-01-01

    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. © 2011 Pinzon et al.

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

    PubMed

    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.

  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. Thermodynamic black di-rings

    SciTech Connect

    Iguchi, Hideo; Mishima, Takashi

    2010-10-15

    Previously the five dimensional S{sup 1}-rotating black rings have been superposed in a concentric way by some solitonic methods, and regular systems of two S{sup 1}-rotating black rings were constructed by the authors and then Evslin and Krishnan (we called these solutions 'black di-rings'). In this place we show some characteristics of the solutions of five dimensional black di-rings, especially in thermodynamic equilibrium. After the summary of the di-ring expressions and their physical quantities, first we comment on the equivalence of the two different solution sets of the black di-rings. Then the existence of thermodynamic black di-rings is shown, in which both isothermality and isorotation between the inner black ring and the outer black ring are realized. We also give detailed analysis of peculiar properties of the thermodynamic black di-ring including discussion about a certain kind of thermodynamic stability (instability) of the system.

  6. 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

  7. Blood versus urine ketone monitoring in a pediatric cohort of patients with type 1 diabetes: a crossover study

    PubMed Central

    Goffinet, Line; Barrea, Thierry; Beauloye, Véronique; Lysy, Philippe A.

    2016-01-01

    Background: The aim of our study was to determine the influence of routine ketone monitoring on hyperglycemic events (HE) and ketosis in youngsters with type 1 diabetes (T1D). Methods: Our single-site, controlled and randomized study was conducted on children and adolescents with T1D outside of remission phase. During two crossover periods of 6 months, patients (n = 22) experiencing HE tested ketones alternatively with a blood ketone meter or urine ketone test strips and gave their opinion on screening methods after completion of clinical trial. Moreover, we evaluated levels of awareness of ketone production in a series of 58 patients and sometimes parents via a multiple-choice questionnaire. Results: Based on self-monitoring data, patients experienced a mean of 4.8 HE/month (range 0–9.3). Patients performed accurate ketone tests more frequently during urine (46%) than during blood-testing (29%) periods (p < 0.05); while globally, 50% of ketone tests were inaccurate (i.e. without HE). Ketosis occurred significantly more often during urine (46.4%) than during blood (14.8%) monitoring (p = 0.01), although no episodes of diabetic ketoacidosis (DKA) were noticed. Duration of hyperglycemia was not different whether patients measured ketones or not, suggesting that ketone monitoring did not affect correction of glycemia. Patients evaluated blood monitoring more frequently as being practical, reliable, and useful compared with urine testing. Scores in the awareness questionnaire were globally low (36.8%) without difference between patients and their parents. Conclusions: Although our study shows differences in outcomes (e.g. accurate use, detection of ketosis) of urine versus blood ketone monitoring, these did not affect the occurrence of HE. Whereas ketone monitoring is part of standardized diabetes education, its implementation in daily routine remains difficult, partly because patient awareness about mechanisms of ketosis is lacking. PMID:28203360

  8. Atmospheric Consequences of the Hydration in Gas Phase of Aldehydes and Ketones

    NASA Astrophysics Data System (ADS)

    Vaida, V.; Axson, J. L.; Maron, M. K.

    2010-12-01

    Aldehydes and ketones are known oxidation products of biogenic and anthropogenic VOCs and have been observed by field studies to be present in aerosol and cloud particles. While the gas-phase chemistry of these compounds is fairly well understood, their modeled concentration and role in SOA formation remains controversial. In aqueous solution aldehydes and ketones hydrate to form alcohols. We explore the hydration of these compounds in the gas phase and examine the water and photon mediated processes of these hydrates. The formation of hydrates can contribute to aerosol growth and formation by partitioning into clouds and aerosols because of their lower vapor pressure and tendency to form intermolecular hydrogen bonds. Hydration of aldehydes and ketones has important consequences to the atmospheric photochemistry of these organic compounds. The experimental approaches employ Fourier transform spectroscopy (FTS) and cavity ringdown spectroscopy (CRDS) to observe the formation of diols and hydrates by these molecules as a function of relative humidity.

  9. A Green Approach for Allylations of Aldehydes and Ketones: Combining Allylborate, Mechanochemistry and Lanthanide Catalyst.

    PubMed

    de Souza, Viviane P; Oliveira, Cristiane K; de Souza, Thiago M; Menezes, Paulo H; Alves, Severino; Longo, Ricardo L; Malvestiti, Ivani

    2016-11-16

    Secondary and tertiary alcohols synthesized via allylation of aldehydes and ketones are important compounds in bioactive natural products and industry, including pharmaceuticals. Development of a mechanochemical method using potassium allyltrifluoroborate salt and water, to successfully perform the allylation of aromatic and aliphatic carbonyl compounds is reported for the first time. By controlling the grinding parameters, the methodology can be selective, namely, very efficient for aldehydes and ineffective for ketones, but by employing lanthanide catalysts, the reactions with ketones can become practically quantitative. The catalyzed reactions can also be performed under mild aqueous stirring conditions. Considering the allylation agent and its by-products, aqueous media, energy efficiency and use of catalyst, the methodology meets most of the green chemistry principles.

  10. Asymmetric anti-selective Michael reaction of imidazole-modified ketones with trans-β-nitroalkenes.

    PubMed

    Yang, Dongxu; Wang, Linqing; Li, Dan; Han, Fengxia; Zhao, Depeng; Wang, Rui

    2015-01-19

    The successful application of imidazole-modified ketones in asymmetric anti-selective Michael reactions with trans-β-nitroalkenes is presented by employing a newly developed 3-bromothiophene-modified chiral diamine ligand. The corresponding conjugate adduct was submitted to further transformations with Grignard reagents to solve the problem of α-site selectivity of simple linear ketones. Additionally, the syn-selective product was obtained by treating the anti-selective adduct with a simple base. In this way, the site-specific products for both diastereomers in the asymmetric conjugate addition of simple ketones to nitroalkenes can be obtained. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Production and elicitation of benzalacetone and the raspberry ketone in cell suspension cultures of Rubus idaeus.

    PubMed

    Pedapudi, S; Chin, C K; Pedersen, H

    2000-01-01

    Production levels of p-coumaric acid (p-CA), p-hydroxyphenylbut-3-ene-2-one (benzalacetone), and p-hydroxyphenyl-2-butanone (raspberry ketone) were measured in raspberry cell suspension cultures to investigate metabolite dynamics in a short (two-step) pathway. Intracellular concentrations of benzalacetone and the raspberry ketone fluctuated during the time course of a normal batch culture cycle but showed higher levels during periods of rapid growth. Cells elicited with the signal coupler methyl jasmonate yielded a 2- to 3-fold increase in metabolite concentrations after 24 h. The results suggest that raspberry ketone production is rapidly inducible during periods of high carbohydrate utilization. It is not an end product, however, and undergoes conversion to subsequent metabolites.

  12. THE NEUROPROTECTIVE PROPERTIES OF CALORIE RESTRICTION, THE KETOGENIC DIET, AND KETONE BODIES

    PubMed Central

    Maalouf, Marwan A.; Rho, Jong M.; Mattson, Mark P.

    2008-01-01

    The therapeutic potential of calorie restriction and the ketogenic diet have been repeatedly demonstrated in clinical settings and in various animal models of neurological disease. The underlying mechanisms involve an improvement in mitochondrial function, a decrease in the expression of apoptotic factors and an increase in the activity of neurotrophic factors. Clinical applications of ketogenic diets have been significantly hampered however by poor tolerability and potentially serious side-effects. Recent research aimed at identifying a mediator that can reproduce the neuroprotective effects of calorie restriction with less demanding changes to dietary intake suggests that ketone bodies might represent an appropriate candidate. Ketone bodies protect neurons against multiple types of neuronal injury and the underlying mechanisms are similar to those of calorie restriction and of the ketogenic diet. The present review describes the neuroprotective effects of calorie restriction, the ketogenic diet and ketone bodies and compare the molecular mechanisms of action of these interventions. PMID:18845187

  13. Modification of Chemical Reactivity via Inclusion Complex Formation: Photochemistry of Dibenzyl Ketones and Benzyl Phenylacetates,

    DTIC Science & Technology

    1986-01-01

    8217 cage effect," % Dibenzyl Ketone a-CD) 1:1.3 99 1 3-CD 1:1 263 91 9 ).-CD 1:1 81 19 DCA 1:6 155 99 0 Dianin’s compdi 1:45 169 95 5 p- Methylbenzyl Benzyl...Ketone zT-CD 1:1.4 229 1 86 1.5 12 95 DCA 1:8 1710 1.5 97 1.5 0 94 Dianin’s compd 1:22 166-167 98 2 100 a- Methylbenzyl Benzy) Ketone 3-CD 1:1 251 1.6...Photolyses of Benzyl Phenylacetates in Various Host Media in Solid State guest~hoet % productsi’ host ratio complex mp. *C AA AB BB p- Methylbenzyl

  14. Rhodium-catalyzed ketone methylation using methanol under mild conditions: formation of α-branched products.

    PubMed

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

    2014-01-13

    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. © 2014 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

  15. Inhibition of carbonyl reductase activity in pig heart by alkyl phenyl ketones.

    PubMed

    Imamura, Yorishige; Narumi, Rika; Shimada, Hideaki

    2007-02-01

    The inhibitory effects of alkyl phenyl ketones on carbonyl reductase activity were examined in pig heart. In this study, carbonyl reductase activity was estimated as the ability to reduce 4-benzoylpyridine to S(-)-alpha-phenyl-4-pyridylmethanol in the cytosolic fraction from pig heart (pig heart cytosol). The order of their inhibitory potencies was hexanophenone > valerophenone > heptanophenone > butyrophenone > propiophenone. The inhibitory potencies of acetophenone and nonanophenone were much lower. A significant relationship was observed between Vmax/Km values for the reduction of alkyl phenyl ketones and their inhibitory potencies for carbonyl reductase activity in pig heart cytosol. Furthermore, hexanophenone was a competitive inhibitor for the enzyme activity. These results indicate that several alkyl phenyl ketones including hexanophenone inhibit carbonyl reductase activity in pig heart cytosol, by acting as substrate inhibitors.

  16. Substituent-controlled reactivity in the Nazarov cyclisation of allenyl vinyl ketones.

    PubMed

    Marx, Vanessa M; Stoddard, Rhonda L; Heverly-Coulson, Gavin S; Burnell, D Jean

    2011-07-11

    Alkyl substitution α to the ketone of an allenyl vinyl ketone enhances Nazarov reactivity by inhibiting alternative pathways involving the allene moiety and through electron donation and/or steric hindrance. This substitution pattern also accelerates Nazarov cyclisation by increasing the population of the reactive conformer and by stabilising the oxyallyl cation intermediate. Furthermore, α substitution by an alkyl group does not alter the regioselectivity of interrupted Nazarov reactions when the oxyallyl cation intermediate is intercepted by addition of an oxygen nucleophile, or by [4+3] cyclisation with acyclic dienes. The regioselectivity of the Nazarov process for allenyl vinyl ketones was determined to be a result of an electronic bias in the oxyallyl cation intermediate. Computational data are consistent with this observation. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Synthesis of dienyl ketones via palladium(II)-catalyzed direct cross-coupling reactions between simple alkenes and vinyl ketones: application to the synthesis of vitamin A1 and bornelone.

    PubMed

    Zhang, Xiang; Wang, Min; Zhang, Ming-Xin; Xu, Yun-He; Loh, Teck-Peng

    2013-11-01

    An efficient and general method for the synthesis of conjugated dienyl ketones via palladium(II) acetate catalyzed direct cross-coupling between simple alkenes and vinyl ketones is reported. This method has been successfully applied for the synthesis of Vitamin A1 and bornelone.

  18. Production and structure elucidation of di- and oligosaccharide lipids (biosurfactants) from Tsukamurella sp. nov.

    PubMed

    Vollbrecht, E; Heckmann, R; Wray, V; Nimtz, M; Lang, S

    1998-11-01

    The bacterium Tsukamurella sp. nov., isolated from soil, was found to produce novel glycolipids when grown on sunflower oil as the sole carbon source. The glycolipids were isolated by chromatography on silica columns and their structures elucidated using a combination of multidimensional NMR and MS techniques. The three main components are 2,3-di-O-acyl-alpha-D-glucopyranosyl-(1-1)-alpha-D-glucopyranose, 2,3-di-O-acyl-beta-D-glucopyranosyl-(1-2)-4,6-di-O-acyl-alpha-D- glucopyranosyl-(1-1)-alpha-D-glucopyranose and 2,3-di-O-acyl-beta-D-glucopyranosyl-(1-2)-beta-D-galactopyranosyl- (1-6)-4,6-di-O-acyl-alpha-D-glucopyranosyl-(1-1)-alpha-D- glucopyranosyl which are linked to fatty acids varying in chain length from C4 to C18. The glycolipids are mainly extracellular but are also found attached to the cell walls. During the cultivation the composition of the glycolipids changed from disaccharide- to tri- and tetrasaccharide lipids. The glycolipids show good surface-active behaviour and have antimicrobial properties.

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

    PubMed

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

    2013-02-15

    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.

  20. [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.

  1. Validation of a portable hand-held whole-blood ketone meter for use in cats.

    PubMed

    Weingart, Christiane; Lotz, Fabian; Kohn, Barbara

    2012-03-01

    Urinary dipsticks are the most frequent method used for screening of ketones in animals, but this method has many drawbacks. In human medicine, portable meters that measure ketones in whole blood have largely replaced urinary dipsticks. The aim of this prospective study was to validate a portable whole-blood ketone meter for use in cats. Sixty-two cats (11 clinically healthy, 51 with diabetes mellitus) were included in the study. The concentration of β-hydroxybuyrate (β-HB) was measured in venous and capillary blood with a hand-held ketone meter (Precision Xceed; assay range 0-8 mmol/L) and compared with a spectrophotometric method. Precision, accuracy, and the effects of hematocrit and anticoagulants were evaluated. Between-run precision using low- and high-concentration control solutions was 8.1% and 2.6%, respectively; within-run coefficient of variation determined using 12 feline blood samples was 2.8%. In the 62 cats, β-HB concentrations measured with the portable ketone meter ranged from 0-7.4 mmol/L (median 0.9 mmol/L). When β-HB concentrations measured by the portable meter were < 4.0 mmol/L there was good agreement with the reference method, but concentrations > 4.0 mmol/L were lower than those obtained by the reference method in 20 of 24 cats (83%). There was good correlation between capillary and venous measurements. Results were not affected by hematocrits from 0.17 to 0.50 L/L, but EDTA was not a suitable anticoagulant. Measurement of β-HB concentration in peripheral or capillary blood by an easy-to-use portable ketone meter was suitable for detecting ketonemia in cats. Underestimation of β-HB concentration was observed at higher values, but results were sufficiently high to aid in diagnosing diabetic ketoacidosis. © 2012 American Society for Veterinary Clinical Pathology.

  2. 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. © The Author 2014. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  3. Photochemical Production of Aldehydes and Ketones from Petroleum Films on Seawater

    NASA Astrophysics Data System (ADS)

    Tarr, M. A.; Rebet, K.; Monin, L.; Bastian, G.

    2016-02-01

    While numerous reports have demonstrated that sunlight results in oxygenation of petroleum in environmental systems, few details are available regarding the specific mechanisms of these reactions. Previous studies have not been able to identify specific chemicals formed when oil is subjected to photochemical transformation. In this study, we have utilized several petroleum samples to investigate the formation of aldehyde and ketone photoproducts. These samples included oil from the MC252 well (source of the Deepwater Horizon spill), surrogate oil provided by BP to represent the MC252 oil, and residual fuel oil (NIST 2717a). Thin films of oil ( 100 μm) were placed over water and irradiated with a solar simulator for the equivalent of 1.5-12 days. After irradiation, the water was carefully separated from the oil and derivatized with 2,4-dinitrophenylhydrazine, a selective derivatization agent for aldehydes and ketones. The derivatized material was then analyzed by HPLC. Additional analysis by electrospray MS was also performed, and absorbance and fluorescence spectra of the underivatized aqueous phase were recorded. For all oils, exposure to sunlight resulted in release of aldehydes and ketones to the aqueous phase. The amount of released photoproducts was proportional to the length of solar exposure, but no production was seen for dark controls. Despite some similarities, the pattern of product formation varied from oil to oil. Addition of dispersant (Corexit 9500a or 9527a) resulted in larger amounts of aldehydes and ketones detected in the aqueous phase after solar irradiation of the oil. Electrospray mass spectrometry was utilized in an attempt to provide structural information about the aldehydes and ketones formed. Results of this study demonstrate that aldehydes and ketones are important photoproducts resulting from solar irradiation of oil on water. These products will affect the transport and bioavailability of oil spilled in aquatic systems.

  4. 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

  5. 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

  6. General and mild Ni(0)-catalyzed α-arylation of ketones using aryl chlorides.

    PubMed

    Fernández-Salas, José A; Marelli, Enrico; Cordes, David B; Slawin, Alexandra M Z; Nolan, Steven P

    2015-03-02

    A general methodology for the α-arylation of ketones using a nickel catalyst has been developed. The new well-defined [Ni(IPr*)(cin)Cl] (1 c) pre-catalyst showed great efficiency for this transformation, allowing the coupling of a wide range of ketones, including acetophenone derivatives, with various functionalised aryl chlorides. This cinnamyl-based Ni-N-heterocyclic carbene (NHC) complex has demonstrated a different behaviour to previously reported NHC-Ni catalysts. Preliminary mechanistic studies suggest a Ni(0)/Ni(II) catalytic cycle to be at play. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Synthesis of Functionalized Dialkyl Ketones From Carboxylic Acid Derivatives and Alkyl Halides

    PubMed Central

    Wotal, Alexander C.; Weix, Daniel J.

    2012-01-01

    Unsymmetrical dialkyl ketones can be directly prepared by the nickel-catalyzed reductive coupling of carboxylic acid chlorides or (2-pyridyl)thioesters with alkyl iodides or benzylic chlorides. A wide variety of functional groups are tolerated by this process, including common nitrogen protecting groups and C-B bonds. Even hindered ketones flanked by tertiary and secondary centers can be formed. The mechanism is proposed to involve the reaction of a (L)Ni(alkyl)2 intermediate with the carboxylic acid derivative. PMID:22360350

  8. Manganese(I)-Catalyzed Enantioselective Hydrogenation of Ketones Using a Defined Chiral PNP Pincer Ligand.

    PubMed

    Garbe, Marcel; Junge, Kathrin; Walker, Svenja; Wei, Zhihong; Jiao, Haijun; Spannenberg, Anke; Bachmann, Stephan; Scalone, Michelangelo; Beller, Matthias

    2017-09-04

    A new chiral manganese PNP pincer complex is described. The asymmetric hydrogenation of several prochiral ketones with molecular hydrogen in the presence of this complex proceeds under mild conditions (30-40 °C, 4 h, 30 bar H2 ). Besides high catalytic activity for aromatic substrates, aliphatic ketones are hydrogenated with remarkable selectivity (e.r. up to 92:8). DFT calculations support an outer sphere hydrogenation mechanism as well as the experimentally determined stereochemistry. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. 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

  10. One-pot Unsymmetrical Ketone Synthesis Employing a Pyrrole-Bearing Formal Carbonyl Dication Linchpin Reagent.

    PubMed

    Heller, Stephen T; Newton, James N; Fu, Tingting; Sarpong, Richmond

    2015-08-17

    A one-pot procedure for the synthesis of unsymmetrical ketones utilizing a pyrrole-bearing carbonyl linchpin reagent (carbonyl linchpin N,O-dimethylhydroxylamine pyrrole; CLAmP) is reported. In contrast to other carbonyl dielectrophile equivalents, CLAmP enables the synthesis of ketones from a variety of organolithium and Grignard reagents. The electrophilic nature of CLAmP enables the addition of less reactive as well as thermally unstable nucleophiles. CLAmP was designed to form kinetically stable tetrahedral intermediates upon the addition of organometallic nucleophiles. Evidence for the existence of persistent tetrahedral intermediates was obtained through in situ IR studies.

  11. 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

  12. One-pot synthesis of β-acetamido ketones using boric acid at room temperature.

    PubMed

    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.

  13. Determination of autoprotolysis constants of ketones using hydrogen-palladium generator electrode.

    PubMed

    Mihajlovi'c, R P; Dzudović, R M; Vajgand, V J

    1993-05-01

    A coulometric-potentiometric method for the determination of autoprotolysis constants of acetone and methyl ethyl ketone, is described. The method is based on the titration of a strong base, i.e., tetrabutylammonium hydroxide with protons obtained by anodic oxidation of hydrogen at an H(2)/pd electrode in the presence of tetrabutylammonium perchlorate as the supporting electrolyte. The titration was carried out in a galvanic cell with glass and calomel electrodes, at 25 degrees . The pK(s) value obtained for acetone and methyl ethyl ketone were 25.82 +/- 0.05 and 26.92 +/- 0.07, respectively.

  14. D-beta-hydroxybutyrate rescues mitochondrial respiration and mitigates features of Parkinson disease.

    PubMed

    Tieu, Kim; Perier, Celine; Caspersen, Casper; Teismann, Peter; Wu, Du-Chu; Yan, Shi-Du; Naini, Ali; Vila, Miquel; Jackson-Lewis, Vernice; Ramasamy, Ravichandran; Przedborski, Serge

    2003-09-01

    Parkinson disease (PD) is a neurodegenerative disorder characterized by a loss of the nigrostriatal dopaminergic neurons accompanied by a deficit in mitochondrial respiration. 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) is a neurotoxin that causes dopaminergic neurodegeneration and a mitochondrial deficit reminiscent of PD. Here we show that the infusion of the ketone body d-beta-hydroxybutyrate (DbetaHB) in mice confers partial protection against dopaminergic neurodegeneration and motor deficits induced by MPTP. These effects appear to be mediated by a complex II-dependent mechanism that leads to improved mitochondrial respiration and ATP production. Because of the safety record of ketone bodies in the treatment of epilepsy and their ability to penetrate the blood-brain barrier, DbetaHB may be a novel neuroprotective therapy for PD.

  15. Nickel N-heterocyclic carbene catalyzed C-C bond formation: a new route to aryl ketones.

    PubMed

    Gu, Li-Jun; Jin, Cheng; Zhang, Hong-Tao

    2015-06-08

    A novel nickel N-heterocyclic carbene catalyzed cross-coupling reaction of aryl aldehydes with boronic esters for the synthesis of aryl ketones was developed. This reaction provides a mild, practical method toward aryl ketones, which are versatile intermediates and building blocks in organic synthesis. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Peroxide promoted tunable decarboxylative alkylation of cinnamic acids to form alkenes or ketones under metal-free conditions.

    PubMed

    Ji, Jing; Liu, Ping; Sun, Peipei

    2015-05-01

    A tunable decarboxylative alkylation of cinnamic acids with alkanes was developed to form alkenes or ketones under transition metal-free conditions. In the presence of DTBP or DTBP/TBHP, the reaction gave alkenes and ketones respectively via a radical mechanism in moderate to good yields.

  17. Chemoselective hydroxylation of aliphatic sp3 C-H bonds using a ketone catalyst and aqueous H2O2.

    PubMed

    Pierce, Conor J; Hilinski, Michael K

    2014-12-19

    The first ketone-catalyzed method for the oxidation of aliphatic C-H bonds is reported. The reaction conditions employ aryl trifluoromethyl ketones in catalytic amounts and hydrogen peroxide as the terminal oxidant. Hydroxylation is stereospecific and chemoselective for tertiary over secondary C-H bonds. A catalytic cycle invoking a dioxirane as the active oxidant is proposed.

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

    USDA-ARS?s Scientific Manuscript database

    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...

  19. Efficient asymmetric transfer hydrogenation of ketones in ethanol with chiral iridium complexes of spiroPAP ligands as catalysts.

    PubMed

    Liu, Wei-Peng; Yuan, Ming-Lei; Yang, Xiao-Hui; Li, Ke; Xie, Jian-Hua; Zhou, Qi-Lin

    2015-04-11

    Highly efficient iridium catalyzed asymmetric transfer hydrogenation of simple ketones with ethanol as a hydrogen donor has been developed. By using chiral spiro iridium catalysts (S)- a series of alkyl aryl ketones were hydrogenated to chiral alcohols with up to 98% ee.

  20. Asymmetric Michael addition of ketones to alkylidene malonates and allylidene malonates via enamine-metal Lewis acid bifunctional catalysis.

    PubMed

    Liu, Lu; Sarkisian, Ryan; Xu, Zhenghu; Wang, Hong

    2012-09-07

    Novel enamine-metal Lewis acid bifunctional catalysts were successfully applied to the asymmetric Michael addition of ketones to alkylidene malonates, offering excellent stereoselectivity (up to >99% ee and >99:1 dr). The asymmetric Michael addition of ketones to allylidene malonates was also achieved.

  1. An In Silico Knockout Model for Gastrointestinal Absorption Using a Systems Pharmacology Approach - Development and Application for Ketones

    PubMed Central

    Shivva, Vittal; Tucker, Ian G.; Duffull, Stephen B.

    2016-01-01

    Gastrointestinal absorption and disposition of ketones is complex. Recent work describing the pharmacokinetics (PK) of d-β-hydroxybutyrate (BHB) following oral ingestion of a ketone monoester ((R)-3-hydroxybutyl (R)-3-hydroxybutyrate) found multiple input sites, nonlinear disposition and feedback on endogenous production. In the current work, a human systems pharmacology model for gastrointestinal absorption and subsequent disposition of small molecules (monocarboxylic acids with molecular weight < 200 Da) was developed with an application to a ketone monoester. The systems model was developed by collating the information from the literature and knowledge gained from empirical population modelling of the clinical data. In silico knockout variants of this systems model were used to explore the mechanism of gastrointestinal absorption of ketones. The knockouts included active absorption across different regions in the gut and also a passive diffusion knockout, giving 10 gut knockouts in total. Exploration of knockout variants has suggested that there are at least three distinct regions in the gut that contribute to absorption of ketones. Passive diffusion predominates in the proximal gut and active processes contribute to the absorption of ketones in the distal gut. Low doses are predominantly absorbed from the proximal gut by passive diffusion whereas high doses are absorbed across all sites in the gut. This work has provided mechanistic insight into the absorption process of ketones, in the form of unique in silico knockouts that have potential for application with other therapeutics. Future studies on absorption process of ketones are suggested to substantiate findings in this study. PMID:27685985

  2. The glucose ketone index calculator: a simple tool to monitor therapeutic efficacy for metabolic management of brain cancer.

    PubMed

    Meidenbauer, Joshua J; Mukherjee, Purna; Seyfried, Thomas N

    2015-01-01

    Metabolic therapy using ketogenic diets (KD) is emerging as an alternative or complementary approach to the current standard of care for brain cancer management. This therapeutic strategy targets the aerobic fermentation of glucose (Warburg effect), which is the common metabolic malady of most cancers including brain tumors. The KD targets tumor energy metabolism by lowering blood glucose and elevating blood ketones (β-hydroxybutyrate). Brain tumor cells, unlike normal brain cells, cannot use ketone bodies effectively for energy when glucose becomes limiting. Although plasma levels of glucose and ketone bodies have been used separately to predict the therapeutic success of metabolic therapy, daily glucose levels can fluctuate widely in brain cancer patients. This can create difficulty in linking changes in blood glucose and ketones to efficacy of metabolic therapy. A program was developed (Glucose Ketone Index Calculator, GKIC) that tracks the ratio of blood glucose to ketones as a single value. We have termed this ratio the Glucose Ketone Index (GKI). The GKIC was used to compute the GKI for data published on blood glucose and ketone levels in humans and mice with brain tumors. The results showed a clear relationship between the GKI and therapeutic efficacy using ketogenic diets and calorie restriction. The GKIC is a simple tool that can help monitor the efficacy of metabolic therapy in preclinical animal models and in clinical trials for malignant brain cancer and possibly other cancers that express aerobic fermentation.

  3. Gold-catalyzed cycloisomerization of 1,7-enyne esters to structurally diverse cis-1,2,3,6-tetrahydropyridin-4-yl ketones.

    PubMed

    Rao, Weidong; Sally; Koh, Ming Joo; Chan, Philip Wai Hong

    2013-04-05

    A synthetic method that relies on gold(I)-catalyzed cycloisomerization of 1,7-enyne esters to prepare highly functionalized cis-1,2,3,6-tetrahydropyridin-4-yl ketone derivatives in good to excellent yields and as a single regio-, diastereo-, and enantiomer is described. By taking advantage of the distinctive differences in the electronic and steric properties between an NHC (NHC = N-heterocyclic carbene) and phosphine ligand in the respective gold(I) complexes, a divergence in product selectivity was observed. In the presence of [PhCNAuIPr](+)SbF6(-) (IPr = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidine) as the catalyst, tandem 1,3-acyloxy migration/6-exo-trig cyclization/1,5-acyl migration of the substrate was found to selectively occur to give the δ-diketone-substituted 1,2,3,6-tetrahydropyridine adduct. In contrast, reactions with the gold(I) phosphine complex [MeCNAu(JohnPhos)](+)SbF6(-) (JohnPhos = (1,1'-biphenyl-2-yl)-di-tert-butylphosphine) as the catalyst was discovered to result in preferential 1,3-acyloxy migration/6-exo-trig cyclization/hydrolysis of the 1,7-enyne ester and formation of the cis-1,2,3,6-tetrahydropyridin-4-yl ketone derivative. The utility of this piperidine forming strategy as a synthetic tool that makes use of 1,7-enyne esters was exemplified by its application to the synthesis of an enantiopure analogue of the bioactive 2,3,4,4a,5,9b-hexahydroindeno[1,2-c]pyridine family of compounds.

  4. Comparative Performance Assessment of Point-of-Care Testing Devices for Measuring Glucose and Ketones at the Patient Bedside

    PubMed Central

    Ceriotti, Ferruccio; Kaczmarek, Ewa; Guerra, Elena; Mastrantonio, Fabrizio; Lucarelli, Fausto; Valgimigli, Francesco; Mosca, Andrea

    2014-01-01

    Background: Point-of-care (POC) testing devices for monitoring glucose and ketones can play a key role in the management of dysglycemia in hospitalized diabetes patients. The accuracy of glucose devices can be influenced by biochemical changes that commonly occur in critically ill hospital patients and by the medication prescribed. Little is known about the influence of these factors on ketone POC measurements. The aim of this study was to assess the analytical performance of POC hospital whole-blood glucose and ketone meters and the extent of glucose interference factors on the design and accuracy of ketone results. Methods: StatStrip glucose/ketone, Optium FreeStyle glucose/ketone, and Accu-Chek Performa glucose were also assessed and results compared to a central laboratory reference method. The analytical evaluation was performed according to Clinical and Laboratory Standards Institute (CLSI) protocols for precision, linearity, method comparison, and interference. Results: The interferences assessed included acetoacetate, acetaminophen, ascorbic acid, galactose, maltose, uric acid, and sodium. The accuracies of both Optium ketone and glucose measurements were significantly influenced by varying levels of hematocrit and ascorbic acid. StatStrip ketone and glucose measurements were unaffected by the interferences tested with exception of ascorbic acid, which reduced the higher level ketone value. The accuracy of Accu-Chek glucose measurements was affected by hematocrit, by ascorbic acid, and significantly by galactose. The method correlation assessment indicated differences between the meters in compliance to ISO 15197 and CLSI 12-A3 performance criteria. Conclusions: Combined POC glucose/ketone methods are now available. The use of these devices in a hospital setting requires careful consideration with regard to the selection of instruments not sensitive to hematocrit variation and presence of interfering substances. PMID:25519295

  5. Comparative performance assessment of point-of-care testing devices for measuring glucose and ketones at the patient bedside.

    PubMed

    Ceriotti, Ferruccio; Kaczmarek, Ewa; Guerra, Elena; Mastrantonio, Fabrizio; Lucarelli, Fausto; Valgimigli, Francesco; Mosca, Andrea

    2015-03-01

    Point-of-care (POC) testing devices for monitoring glucose and ketones can play a key role in the management of dysglycemia in hospitalized diabetes patients. The accuracy of glucose devices can be influenced by biochemical changes that commonly occur in critically ill hospital patients and by the medication prescribed. Little is known about the influence of these factors on ketone POC measurements. The aim of this study was to assess the analytical performance of POC hospital whole-blood glucose and ketone meters and the extent of glucose interference factors on the design and accuracy of ketone results. StatStrip glucose/ketone, Optium FreeStyle glucose/ketone, and Accu-Chek Performa glucose were also assessed and results compared to a central laboratory reference method. The analytical evaluation was performed according to Clinical and Laboratory Standards Institute (CLSI) protocols for precision, linearity, method comparison, and interference. The interferences assessed included acetoacetate, acetaminophen, ascorbic acid, galactose, maltose, uric acid, and sodium. The accuracies of both Optium ketone and glucose measurements were significantly influenced by varying levels of hematocrit and ascorbic acid. StatStrip ketone and glucose measurements were unaffected by the interferences tested with exception of ascorbic acid, which reduced the higher level ketone value. The accuracy of Accu-Chek glucose measurements was affected by hematocrit, by ascorbic acid, and significantly by galactose. The method correlation assessment indicated differences between the meters in compliance to ISO 15197 and CLSI 12-A3 performance criteria. Combined POC glucose/ketone methods are now available. The use of these devices in a hospital setting requires careful consideration with regard to the selection of instruments not sensitive to hematocrit variation and presence of interfering substances. © 2014 Diabetes Technology Society.

  6. α,β-Functionalization of saturated ketones with anthranils via Cu-catalyzed sequential dehydrogenation/aza-Michael addition/annulation cascade reactions in one-pot.

    PubMed

    Tiwari, Dipak Kumar; Phanindrudu, Mandalaparthi; Wakade, Sandip Balasaheb; Nanubolu, Jagadeesh Babu; Tiwari, Dharmendra Kumar

    2017-05-09

    An efficient method to access functionalized quinolines from the readily available saturated ketones and anthranils has been explored. This one-pot cascade reaction involves the in situ generation of α,β-unsaturated ketones by the copper catalysed dehydrogenation of saturated ketones followed by the aza-Michael addition of anthranils and subsequent annulation.

  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

    2016-06-08

    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. A Nucleophilic Strategy for Enantioselective Intermolecular α-Amination: Access to Enantioenriched α-Arylamino Ketones

    PubMed Central

    Miles, Dillon H.; Guasch, Joan; Toste, F. Dean

    2016-01-01

    The enantioselective addition of anilines to azoalkenes was accomplished through the use of a chiral phosphoric acid catalyst. The resulting α-arylamino hydrazones were obtained in good yields and excellent enantioselectivities and provide access to enantioenriched α-arylamino ketones. A serendipitous kinetic resolution of racemic α-arylamino hydrazones is also described. PMID:26066512

  9. Unexpected formation of aryl ketones by palladium-catalyzed coupling of aryl bromides with vinylic acetates.

    PubMed

    Jean, Mickaël; Renault, Jacques; Uriac, Philippe; Capet, Marc; van de Weghe, Pierre

    2007-08-30

    A palladium-catalyzed coupling reaction of aryl bromides with vinylic acetates in the presence of tributyltin methoxide has been described. Unexpected formation of aryl ketones was obtained. Preliminary mechanistic studies indicated that the reaction proceeded by the addition of the aryl moiety in the coordination sphere of palladium to a ketene.

  10. Stereoselective double Friedel-Crafts alkylation of indoles with divinyl ketones.

    PubMed

    Silvanus, Andrew C; Heffernan, Stephen J; Liptrot, David J; Kociok-Köhn, Gabriele; Andrews, Benjamin I; Carbery, David R

    2009-03-05

    A tandem double Friedel-Crafts reaction of indoles and nonsymmetrical divinyl ketones has been achieved. The tandem reaction forms complex [6-5-7]-tricyclic indoles in excellent yields. The reaction is completely regioselective and offers high levels of syn diastereoselectivity. The reaction is also seen to be sensitive to substrate structure and catalyst.

  11. Two-carbon homologation of aldehydes and ketones to a,ß-unsaturated aldehydes

    USDA-ARS?s Scientific Manuscript database

    Phosphonate reagents were developed for the two-carbon homologation of aldehydes or ketones to unbranched- or methyl-branched a,ß-unsaturated aldehydes. The phosphonate reagents, diethyl methylformyl-2-phosphonate dimethylhydrazone and diethyl ethylformyl-2-phosphonate dimethylhydrazone, contained a...

  12. Regulation of hypothalamic neuronal sensing and food intake by ketone bodies and fatty acids.

    PubMed

    Le Foll, Christelle; Dunn-Meynell, Ambrose A; Miziorko, Henri M; Levin, Barry E

    2014-04-01

    Metabolic sensing neurons in the ventromedial hypothalamus (VMH) alter their activity when ambient levels of metabolic substrates, such as glucose and fatty acids (FA), change. To assess the relationship between a high-fat diet (HFD; 60%) intake on feeding and serum and VMH FA levels, rats were trained to eat a low-fat diet (LFD; 13.5%) or an HFD in 3 h/day and were monitored with VMH FA microdialysis. Despite having higher serum levels, HFD rats had lower VMH FA levels but ate less from 3 to 6 h of refeeding than did LFD rats. However, VMH β-hydroxybutyrate (β-OHB) and VMH-to-serum β-OHB ratio levels were higher in HFD rats during the first 1 h of refeeding, suggesting that VMH astrocyte ketone production mediated their reduced intake. In fact, using calcium imaging in dissociated VMH neurons showed that ketone bodies overrode normal FA sensing, primarily by exciting neurons that were activated or inhibited by oleic acid. Importantly, bilateral inhibition of VMH ketone production with a 3-hydroxy-3-methylglutaryl-CoA synthase inhibitor reversed the 3- to 6-h HFD-induced inhibition of intake but had no effect in LFD-fed rats. These data suggest that a restricted HFD intake regimen inhibits caloric intake as a consequence of FA-induced VMH ketone body production by astrocytes.

  13. 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

    2016-06-06

    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. © 2016 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  14. Engineering of Ralstonia eutropha H16 for Autotrophic and Heterotrophic Production of Methyl Ketones

    PubMed Central

    Müller, Jana; MacEachran, Daniel; Burd, Helcio; Sathitsuksanoh, Noppadon; Bi, Changhao; Yeh, Yi-Chun; Lee, Taek Soon; Hillson, Nathan J.; Chhabra, Swapnil R.; Singer, Steven W.

    2013-01-01

    Ralstonia eutropha is a facultatively chemolithoautotrophic bacterium able to grow with organic substrates or H2 and CO2 under aerobic conditions. Under conditions of nutrient imbalance, R. eutropha produces copious amounts of poly[(R)-3-hydroxybutyrate] (PHB). Its ability to utilize CO2 as a sole carbon source renders it an interesting new candidate host for the production of renewable liquid transportation fuels. We engineered R. eutropha for the production of fatty acid-derived, diesel-range methyl ketones. Modifications engineered in R. eutropha included overexpression of a cytoplasmic version of the TesA thioesterase, which led to a substantial (>150-fold) increase in fatty acid titer under certain conditions. In addition, deletion of two putative β-oxidation operons and heterologous expression of three genes (the acyl coenzyme A oxidase gene from Micrococcus luteus and fadB and fadM from Escherichia coli) led to the production of 50 to 65 mg/liter of diesel-range methyl ketones under heterotrophic growth conditions and 50 to 180 mg/liter under chemolithoautotrophic growth conditions (with CO2 and H2 as the sole carbon source and electron donor, respectively). Induction of the methyl ketone pathway diverted substantial carbon flux away from PHB biosynthesis and appeared to enhance carbon flux through the pathway for biosynthesis of fatty acids, which are the precursors of methyl ketones. PMID:23686271

  15. 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.

  16. How Cinchona Alkaloid-Derived Primary Amines Control Asymmetric Electrophilic Fluorination of Cyclic Ketones

    PubMed Central

    2015-01-01

    The origin of selectivity in the α-fluorination of cyclic ketones catalyzed by cinchona alkaloid-derived primary amines is determined with density functional calculations. The chair preference of a seven-membered ring at the fluorine transfer transition state is key in determining the sense and level of enantiofacial selectivity. PMID:24967514

  17. Poor adherence to ketone testing in patients with Type 1 Diabetes

    USDA-ARS?s Scientific Manuscript database

    Diabetic ketoacidosis (DKA) is an acute, still common, and preventable complication of type 1 diabetes (T1D) associated with increased health care costs, morbidity, and mortality. Clinical recommendations advise self-monitoring of ketones in people with T1D during hyperglycemia and illness to allow ...

  18. Identification of two phytotoxins, blumenol A and grasshopper ketone, in the allelopathic Japanese rice variety Awaakamai.

    PubMed

    Kato-Noguchi, Hisashi; Tamura, Kazuya; Sasaki, Hiroaki; Suenaga, Kiyotake

    2012-05-01

    Aqueous methanol extracts of the traditional rice (Oryza sativa) variety Awaakamai, which is known to have the greatest allelopathic activity among Japanese traditional rice varieties, inhibited the growth of roots and shoots of cress (Lepidium sativum), lettuce (Lactuca sativa), timothy (Phleum pratense), Digitaria sanguinalis, Lolium multiflorum and Echinochloa crus-galli. Increasing the extract concentration increased the inhibition, suggesting that the extract of Awaakamai contains growth inhibitory substances. The extract of Awaakamai was purified and two main growth inhibitory substances were isolated and determined by spectral data as blumenol A and grasshopper ketone. Blumenol A and grasshopper ketone, respectively, inhibited the growth of cress shoots and roots at concentrations greater than 10 and 30 μmol/L. The concentrations required for 50% growth inhibition on cress roots and shoots were 84 and 27 μmol/L, respectively, for blumenol A, and 185 and 76 μmol/L, respectively, for grasshopper ketone. These results suggest that blumenol A and grasshopper ketone may contribute to the growth inhibitory effect of Awaakamai and may play an important role in the allelopathy of Awaakamai. Copyright © 2012 Elsevier GmbH. All rights reserved.

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

    USDA-ARS?s Scientific Manuscript database

    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. 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.

  2. Field captures of wild melon fly (Diptera: Tephritidae) with an improved male attractant, raspberry ketone formate.

    PubMed

    Jang, Eric B; Casana-Giner, Victor; Oliver, James E

    2007-08-01

    Field-trapping evaluations of the new male attractant, formic acid 4-(3-oxobutyl) phenyl ester (raspberry ketone formate [RKF]) were conducted in Hawaii with wild populations of melon flies, Bactrocera cucurbitae Coquillett (Diptera: Tephritidae), to determine its activity in the field and to evaluate new plastic matrix formulations. All tests were compared with the standard melon fly attractant 4-(4-acetoxyphenyl) -2-butanone (cuelure [CL]), which is the attractant of choice for detection programs aimed at melon fly and other cuelure-responding Bactrocera fruit flies. Results of these tests over a range of doses on cotton wicks showed that at a 1-g dose raspberry ketone formate was 1.5-2 times more attractive compared with cuelure for up to 11 wk in the field. Lower doses applied on cotton wicks were less active, presumably due to hydrolysis of RKF to raspberry ketone. Raspberry ketone formate embedded in a plastic plug formulation also was field tested, and it was shown to be more attractive to male melon fly compared with cuelure. The use of this new attractant in control and detection programs is discussed.

  3. Renewable high-density spiro-fuels from lignocellulose-derived cyclic ketones.

    PubMed

    Xie, Junjian; Zhang, Xiangwen; Pan, Lun; Nie, Genkuo; E, Xiu-Tian-Feng; Liu, Qing; Wang, Peng; Li, Yafei; Zou, Ji-Jun

    2017-09-14

    Renewable high-density spiro-fuels are synthesized from lignocellulose-derived cyclic ketones for the first time, which show higher density, higher neat heat of combustion and lower freezing point compared with other biofuels synthesized from the same feedstock, and thus represent a new type of renewable high-density fuel attractive for practical applications.

  4. Stoichiometric Reactions of Acylnickel(II) Complexes with Electrophiles and the Catalytic Synthesis of Ketones

    PubMed Central

    2015-01-01

    Acylnickel(II) complexes feature prominently in cross-electrophile coupling (XEC) reactions that form ketones, yet their reactivity has not been systematically investigated. We present here our studies on the reactivity of acylnickel(II) complexes with a series of carbon electrophiles. Bromobenzene, α-chloroethylbenzene, bromooctane, and iodooctane were reacted with (dtbbpy)NiII(C(O)C5H11)(Br) (1b) and (dtbbpy)NiII(C(O)tolyl)(Br) (1c) to form a variety of organic products. While reactions with bromobenzene formed complex mixtures of ketones, reactions with α-chloroethylbenzene were highly selective for the cross-ketone product. Reactions with iodooctane and bromooctane also produced the cross-ketone product, but in intermediate yield and selectivity. In most cases the presence or absence of a chemical reductant (zinc) had only a small effect on the selectivity of the reaction. The coupling of 1c with iodooctane (60% yield) was translated into a catalytic reaction, the carbonylative coupling of bromoarenes with primary bromoalkanes (six examples, 60% average yield). PMID:25364092

  5. A theoretical study of the mechanism of phosphine-catalyzed hydroalkoxylation of methyl vinyl ketone.

    PubMed

    Wang, Xin; Li, Shuhua; Jiang, Yuansheng

    2005-12-01

    The mechanism of phosphine-catalyzed hydroalkoxylation of the methyl vinyl ketone has been investigated by the second-order Møller-Plesset perturbation theory and the conductor-like polarized continuum model. The free energy reaction profiles of the reaction in both gas phase and solution phase are explored and compared. Our results suggest that the first stage of the studied reaction is the generation of the base (the methoxide anion) with the help of trialkylphosphine, and the second stage is the hydroalkoxylation of the methyl vinyl ketone catalyzed by this base. In the first stage, trialkylphosphine first adds to the methyl vinyl ketone to form a phosphonium enolate intermediate and then this species deprotonates a methanol molecule to generate a methoxide anion. Both steps involve free energy barriers of about 20 kcal/mol. In the second stage, both the addition of the methoxide anion to the methyl vinyl ketone and the proton transfer process from methanol to the methoxyl enolate anion intermediate have activation free energies of about 16 kcal/mol. The reaction in the second stage is exothermic by 10.2 kcal/mol at room temperature. A comparison of the free energy reaction profiles in the gas phase and the solution phase demonstrated that the generation of the methoxide anion could only occur in the presence of the polar solvents. The mechanism proposed in the present work is in reasonable agreement with the known experimental facts.

  6. Photodissociation dynamics of dicyclopropyl ketone at 193 nm: Isomerization of the cyclopropyl ligand

    NASA Astrophysics Data System (ADS)

    Clegg, Samuel M.; Parsons, Bradley F.; Klippenstein, Stephen J.; Osborn, David L.

    2003-10-01

    The photodissociation dynamics of dicyclopropyl ketone are investigated using time-resolved Fourier transform infrared spectroscopy and photofragment ion imaging spectroscopy. The photodissociation products are C3H5+CO+C3H5, and the isomerization dynamics of C3H5 are the focus of this paper. Electronic structure calculations are used to define the potential energy surface, while a two-step phase space theory model predicts excitation in the CO product. The vibrational energy distribution of the CO product is not described by this statistical distribution, and is more excited than that observed in the analogous dissociation of acetone. The translational energy distribution of CO indicates an exit barrier on the potential energy surface. Contrary to expectations based on the photodissociation of other aliphatic ketones, the hydrocarbon products are not cyclopropyl radicals. Instead, the excited dicyclopropyl ketone undergoes a ring-opening isomerization to form diallyl ketone, followed by dissociation producing allyl radicals and carbon monoxide. Some of the allyl radicals have sufficient internal energy to decompose to allene+H.

  7. A one-pot approach to Δ2-isoxazolines from ketones and arylacetylenes.

    PubMed

    Schmidt, Elena Yu; Tatarinova, Inna V; Ivanova, Elena V; Zorina, Nadezhda V; Ushakov, Igor' A; Trofimov, Boris A

    2013-01-04

    The sequential reaction of ketones with arylacetylenes and hydroxylamine in the presence of KOBu(t)/DMSO followed by the treatment of the reaction mixture with H(2)O and KOH leads to Δ(2)-isoxazolines in up to 88% yield.

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

    USDA-ARS?s Scientific Manuscript database

    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 ...

  9. A stable germanone as the first isolated heavy ketone with a terminal oxygen atom

    NASA Astrophysics Data System (ADS)

    Li, Liangchun; Fukawa, Tomohide; Matsuo, Tsukasa; Hashizume, Daisuke; Fueno, Hiroyuki; Tanaka, Kazuyoshi; Tamao, Kohei

    2012-05-01

    The carbon-oxygen double bond of ketones (R2C=O) makes them among the most important organic compounds, but their homologues, heavy ketones with an E=O double bond (E = Si, Ge, Sn or Pb), had not been isolated as stable compounds. Their unavailability as monomeric molecules is ascribed to their high tendency for intermolecular oligomerization or polymerization via opening of the E=O double bond. Can such an intermolecular process be inhibited by bulky protecting groups? We now report that it can, with the first isolation of a monomeric germanium ketone analogue (Eind)2Ge=O (Eind = 1,1,3,3,5,5,7,7-octaethyl-s-hydrindacen-4-yl), stabilized by appropriately designed bulky Eind groups, with a planar tricoordinate germanium atom. Computational studies and chemical reactions suggest the Ge=O double bond is highly polarized with a contribution of a charge-separated form (Eind)2Ge+-O-. The germanone thus exhibits unique reactivities that are not observed with ordinary ketones, including the spontaneous trapping of CO2 gas to provide a cyclic addition product.

  10. Catalyst-controlled dioxygenation of olefins: an approach to peroxides, alcohols, and ketones.

    PubMed

    Xia, Xiao-Feng; Zhu, Su-Li; Gu, Zhen; Wang, Haijun; Li, Wei; Liu, Xiang; Liang, Yong-Min

    2015-06-05

    An efficient catalytic approach for the synthesis of substituted peroxides, alcohols, and ketones through a catalyst-controlled highly selective dioxygenation of olefins has been demonstrated. The reported methods are mild and practical, can be switched by the selection of different catalytic systems, and employ peroxide as an oxidant and a reagent at room temperature.

  11. Lewis acid/CpRu dual catalysis in the enantioselective decarboxylative allylation of ketone enolates.

    PubMed

    Linder, David; Austeri, Martina; Lacour, Jérôme

    2009-10-07

    The addition of a Lewis acidic metal triflate salt Mg(OTf)(2) as co-catalyst in the CpRu-catalyzed decarboxylative allylation of in situ-generated ketone enolates allows the reaction to proceed at lower temperature with higher regio- and enantioselectivity. Even so-far-unreactive substrates react.

  12. 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.

  13. Electrochemically reduced graphene oxide / sulfonated polyether ether ketone composite membrane for electrochemical applications

    NASA Astrophysics Data System (ADS)

    Seetharaman, S.; Ramya, K.; Dhathathreyan, K. S.

    2013-06-01

    A simple and effective method for the preparation of sulfonated polyether ether ketone (SPEEK) based composites with electrochemical reduced graphene oxide (EGO) as inorganic fillers has been described. The resulting dispersions are homogeneous and the cast membranes show significant improvement on tensile strength and thermal properties. It has high ionic conductivity and is cost effective making it a promising alternative membrane for electrochemical applications.

  14. Highly efficient ligands for palladium-catalyzed asymmetric alkylation of ketone enolates.

    PubMed

    You, S L; Hou, X L; Dai, L X; Zhu, X Z

    2001-01-25

    [figure: see text] Ferrocene-modified chiral pocket ligands have been studied in the palladium-catalyzed asymmetric alkylation of simple ketone enolates, in which (R,R,Sp,Sp)-1 containing two pairs of matched chiralities, central chirality and planar chirality, behaved very efficiently in this reaction and up to 95% ee value was achieved.

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

    USDA-ARS?s Scientific Manuscript database

    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...

  17. Electrochemical preparation of ether ketones from (poly)propylene glycol monoethers

    SciTech Connect

    Snoble, K.A.J.

    1984-02-14

    This invention is a method for preparing an ether ketone comprising electrolyzing a solution containing a (poly)propylene glycol monoether, hydroxyl ions and optionally water in an electrolytic cell having an anode at least partially coated with nickel peroxide, silver peroxide, cobalt peroxide or copper peroxide.

  18. Reactivity and stereoselectivity of 6π and nazarov electrocyclizations of bridged bicyclic trienes and divinyl ketones.

    PubMed

    Patel, Ashay; West, F G; Houk, K N

    2015-03-06

    The 6π electrocyclizations and Nazarov cyclizations of a series of bridged bicyclic substrates were modeled with the M06-2X density functional and the def2-TZVPP basis set, and the factors responsible for the reactivities of these substrates and the stereoselectivities of their ring closures were identified. The ring closures of these bridged bicyclic trienes are up to a million-fold faster (ΔΔG(⧧) = 10 kcal mol(-1)) than that of 1,3,5-hexatriene, despite the absence of any activating functional groups. Three effects, preorganization, predistortion, and a CH π interaction, are responsible for this sizable difference in reactivity. Stereoselectivity is partially controlled by torsional effects, but for highly exo selective electrocyclizations, it is reinforced by a second effect (either a CH π interaction or a steric clash). The absence of this second effect in the ring closures of several divinyl ketones explains the reduced selectivity of these ring closures. In one case, a divinyl ketone (ketone 6) undergoes Nazarov cyclization to yield the endo product preferentially. For this example, through-space interaction of a nonconjugated alkene with the divinyl ketone π system in the endo transition state and a steric effect override the intrinsic exo selectivity.

  19. 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

  20. Effects of Insecticidal Ketones Present in Mint Plants on GABAA Receptor from Mammalian Neurons.

    PubMed

    Sánchez-Borzone, Mariela Eugenia; Marin, Leticia Delgado; García, Daniel Asmed

    2017-01-01

    The genus Mentha, an important member of the Lamiaceae family, is represented by many species commonly known as mint. The insecticidal activity of Mentha oil and its main components has been tested and established against various insects/pests. Among these, the ketone monoterpenes that are most common in different Mentha species demonstrated insect toxicity, with pulegone being the most active, followed by carvone and menthone. Considering that the GABAA receptor (GABAA-R) is one of the main insecticide targets on neurons, and that pulegone would modulate the insect GABA system, it may be expected that the insecticidal properties of Mentha ketones are mediated by their interaction with this receptor. In order to discern the pharmacological actions of these products when used as insecticides on mammalian organisms, we evaluated the pharmacologic activity of ketones, commonly present in Mentha plants, on native GABAA-R from rats. Determination of ketones effects on allosterically enhanced benzodiazepine binding, using primary cultures of cortical neurons, which express functional receptors and MTT assay to evaluate their cell toxicity. Our results seem to indicate that ketone components of Mentha, with proven repellent or insecticide activity, were able to behave as GABAA-R negative allosteric modulators in murine cells and consequently could exhibit convulsant activity in mammalians. Only pulegone at the highest assayed concentration (2 mM) showed a significant reduction in cell viability after exposure for 24 hr. The present results strongly suggest that the ketone components of Mentha are able to exhibit convulsant activity in mammalian organisms, but functional assays and in vivo experiments would be necessary to corroborate this proposed action. The pharmacological activity of insecticide ketones, commonly present in Mentha plants, was evaluated on native GABAA receptor from mammalian neurons.All studied compounds: pulegone, menthone and dihydrocarvone, were

  1. Effects of Insecticidal Ketones Present in Mint Plants on GABAA Receptor from Mammalian Neurons

    PubMed Central

    Sánchez-Borzone, Mariela Eugenia; Marin, Leticia Delgado; García, Daniel Asmed

    2017-01-01

    Background: The genus Mentha, an important member of the Lamiaceae family, is represented by many species commonly known as mint. The insecticidal activity of Mentha oil and its main components has been tested and established against various insects/pests. Among these, the ketone monoterpenes that are most common in different Mentha species demonstrated insect toxicity, with pulegone being the most active, followed by carvone and menthone. Considering that the GABAA receptor (GABAA-R) is one of the main insecticide targets on neurons, and that pulegone would modulate the insect GABA system, it may be expected that the insecticidal properties of Mentha ketones are mediated by their interaction with this receptor. Objective: In order to discern the pharmacological actions of these products when used as insecticides on mammalian organisms, we evaluated the pharmacologic activity of ketones, commonly present in Mentha plants, on native GABAA-R from rats. Materials and Methods: Determination of ketones effects on allosterically enhanced benzodiazepine binding, using primary cultures of cortical neurons, which express functional receptors and MTT assay to evaluate their cell toxicity. Results: Our results seem to indicate that ketone components of Mentha, with proven repellent or insecticide activity, were able to behave as GABAA-R negative allosteric modulators in murine cells and consequently could exhibit convulsant activity in mammalians. Only pulegone at the highest assayed concentration (2 mM) showed a significant reduction in cell viability after exposure for 24 hr. Conclusion: The present results strongly suggest that the ketone components of Mentha are able to exhibit convulsant activity in mammalian organisms, but functional assays and in vivo experiments would be necessary to corroborate this proposed action. SUMMARY The pharmacological activity of insecticide ketones, commonly present in Mentha plants, was evaluated on native GABAA receptor from mammalian

  2. Mechanisms involved in ketone body release by rat liver cells: influence of pH and bicarbonate

    SciTech Connect

    Fafournoux, P.; Demigne, C.; Remesy, C.

    1987-02-01

    The aim of the present work is to study the intra- and extracellular concentration gradient of ketone bodies across the hepatic cell membrane, ketone bodies released by liver cells, and the effects of changes in acid-base status on these processes. Ketone bodies appeared to be released by liver cells against a concentration gradient both in vivo and in vitro. In vitro, a decrease in external pH and bicarbonate gradient measured with ( UC)- and (TH)-labelled compounds, and efflux rates. Analysis of the distribution ratio of ketone bodies as a function of pH across the cell membrane indicates that additional factors must be invoked to account for the observed distribution ratios. These data along with measurement of ketone body efflux are consistent with the existence of a system promoting the efflux of ketone bodies from liver cells, which is trans-stimulated by external bicarbonate. In vivo, ketogenesis was also inhibited by acidosis, and slightly enhanced by bicarbonate infusion, although this was not solely due to effects on transfer across the cell membrane. The study indicates that the hepatic release of ketone bodies might be auto-limited by ketoacidosis.

  3. Detection of Ketones by a Novel Technology: Dipolar Proton Transfer Reaction Mass Spectrometry (DP-PTR-MS).

    PubMed

    Pan, Yue; Zhang, Qiangling; Zhou, Wenzhao; Zou, Xue; Wang, Hongmei; Huang, Chaoqun; Shen, Chengyin; Chu, Yannan

    2017-03-17

    Proton transfer reaction mass spectrometry (PTR-MS) has played an important role in the field of real-time monitoring of trace volatile organic compounds (VOCs) due to its advantages such as low limit of detection (LOD) and fast time response. Recently, a new technology of proton extraction reaction mass spectrometry (PER-MS) with negative ions OH(-) as the reagent ions has also been presented, which can be applied to the detection of VOCs and even inorganic compounds. In this work, we combined the functions of PTR-MS and PER-MS in one instrument, thereby developing a novel technology called dipolar proton transfer reaction mass spectrometry (DP-PTR-MS). The selection of PTR-MS mode and PER-MS mode was achieved in DP-PTR-MS using only water vapor in the ion source and switching the polarity. In this experiment, ketones (denoted by M) were selected as analytes. The ketone (molecular weight denoted by m) was ionized as protonated ketone [M + H](+) [mass-to-charge ratio (m/z) m + 1] in PTR-MS mode and deprotonated ketone [M - H](-) (m/z m - 1) in PER-MS mode. By comparing the m/z value of the product ions in the two modes, the molecular weight of the ketone can be positively identified as m. Results showed that whether it is a single ketone sample or a mixed sample of eight kinds of ketones, the molecular weights can be detected with DP-PTR-MS. The newly developed DP-PTR-MS not only maintains the original advantages of PTR-MS and PER-MS in sensitive and rapid detection of ketones, but also can estimate molecular weight of ketones. Graphical Abstract ᅟ.

  4. Detection of Ketones by a Novel Technology: Dipolar Proton Transfer Reaction Mass Spectrometry (DP-PTR-MS)

    NASA Astrophysics Data System (ADS)

    Pan, Yue; Zhang, Qiangling; Zhou, Wenzhao; Zou, Xue; Wang, Hongmei; Huang, Chaoqun; Shen, Chengyin; Chu, Yannan

    2017-05-01

    Proton transfer reaction mass spectrometry (PTR-MS) has played an important role in the field of real-time monitoring of trace volatile organic compounds (VOCs) due to its advantages such as low limit of detection (LOD) and fast time response. Recently, a new technology of proton extraction reaction mass spectrometry (PER-MS) with negative ions OH- as the reagent ions has also been presented, which can be applied to the detection of VOCs and even inorganic compounds. In this work, we combined the functions of PTR-MS and PER-MS in one instrument, thereby developing a novel technology called dipolar proton transfer reaction mass spectrometry (DP-PTR-MS). The selection of PTR-MS mode and PER-MS mode was achieved in DP-PTR-MS using only water vapor in the ion source and switching the polarity. In this experiment, ketones (denoted by M) were selected as analytes. The ketone (molecular weight denoted by m) was ionized as protonated ketone [M + H]+ [mass-to-charge ratio ( m/z) m + 1] in PTR-MS mode and deprotonated ketone [M - H]- ( m/z m - 1) in PER-MS mode. By comparing the m/z value of the product ions in the two modes, the molecular weight of the ketone can be positively identified as m. Results showed that whether it is a single ketone sample or a mixed sample of eight kinds of ketones, the molecular weights can be detected with DP-PTR-MS. The newly developed DP-PTR-MS not only maintains the original advantages of PTR-MS and PER-MS in sensitive and rapid detection of ketones, but also can estimate molecular weight of ketones.

  5. Detection of Ketones by a Novel Technology: Dipolar Proton Transfer Reaction Mass Spectrometry (DP-PTR-MS)

    NASA Astrophysics Data System (ADS)

    Pan, Yue; Zhang, Qiangling; Zhou, Wenzhao; Zou, Xue; Wang, Hongmei; Huang, Chaoqun; Shen, Chengyin; Chu, Yannan

    2017-03-01

    Proton transfer reaction mass spectrometry (PTR-MS) has played an important role in the field of real-time monitoring of trace volatile organic compounds (VOCs) due to its advantages such as low limit of detection (LOD) and fast time response. Recently, a new technology of proton extraction reaction mass spectrometry (PER-MS) with negative ions OH- as the reagent ions has also been presented, which can be applied to the detection of VOCs and even inorganic compounds. In this work, we combined the functions of PTR-MS and PER-MS in one instrument, thereby developing a novel technology called dipolar proton transfer reaction mass spectrometry (DP-PTR-MS). The selection of PTR-MS mode and PER-MS mode was achieved in DP-PTR-MS using only water vapor in the ion source and switching the polarity. In this experiment, ketones (denoted by M) were selected as analytes. The ketone (molecular weight denoted by m) was ionized as protonated ketone [M + H]+ [mass-to-charge ratio (m/z) m + 1] in PTR-MS mode and deprotonated ketone [M - H]- (m/z m - 1) in PER-MS mode. By comparing the m/z value of the product ions in the two modes, the molecular weight of the ketone can be positively identified as m. Results showed that whether it is a single ketone sample or a mixed sample of eight kinds of ketones, the molecular weights can be detected with DP-PTR-MS. The newly developed DP-PTR-MS not only maintains the original advantages of PTR-MS and PER-MS in sensitive and rapid detection of ketones, but also can estimate molecular weight of ketones.

  6. Electronic Nature of Ketone Directing Group as a Key To Control C-2 vs C-4 Alkenylation of Indoles.

    PubMed

    Lanke, Veeranjaneyulu; Bettadapur, Kiran R; Prabhu, Kandikere Ramaiah

    2016-11-04

    A novel mode of achieving site selectivity between C-2 and C-4 positions in the indole framework by altering the property of the ketone directing group is disclosed. Methyl ketone, as directing group, furnishes exclusively C-2 alkenylated product, whereas trifluoromethyl ketone changes the selectivity to C-4, indicating that the electronic nature of the directing group controls the unusual choice between a 5-membered and a 6-membered metallacycle. The screening of other carbonyl-derived directing groups reveals that strong and weak directing groups exhibit opposite selectivity. Experimental controls and deuteration experiments lend support to the proposed mechanism.

  7. Asymmetric synthesis of 2,3-dihydropyrroles by ring-opening/cyclization of cyclopropyl ketones using primary amines.

    PubMed

    Xia, Yong; Liu, Xiaohua; Zheng, Haifeng; Lin, Lili; Feng, Xiaoming

    2015-01-02

    The asymmetric ring-opening/cyclization of cyclopropyl ketones with primary amine nucleophiles was catalyzed by a chiral N,N'-dioxide/scandium(III) complex through a kinetic resolution process. A broad range of cyclopropyl ketones and primary amines are suitable substrates of this reaction. The corresponding products were afforded in excellent enantioselectivities and yields (up to 97 % ee and 98 % yield) under mild reaction conditions. This method provides a promising access to chiral 2,3-dihydropyrroles as well as an effective procedure for the kinetic resolution of 2-substituted cyclopropyl ketones. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Highly functionalized tertiary-carbinols and carbinamines from the asymmetric γ-alkoxyallylboration of ketones and ketimines with the borabicyclodecanes.

    PubMed

    Muñoz-Hernández, Lorell; Seda, Luis A; Wang, Bo; Soderquist, John A

    2014-08-01

    The first asymmetric γ-alkoxyallylboration of representative ketones provides β-alkoxy tert-homoallylic alcohols 10 whose diastereoselectivities range from 99% syn (acetophenone) to 99% anti (pinacolone) both with high ee (>95%). This distribution is attributable to the c/t isomerization of the BBD reagents and the greater reactivity of 7 vs 1 and of aromatic vs alkyl ketones. A ketone-based direct synthesis of a fostriecin intermediate and the tert-amine 26 are reported, each with high selectivities.

  9. Microwave-assisted synthesis of a pyrazolyl ketone library for evaluation as p38 MAPK inhibitors in Werner syndrome cells.

    PubMed

    Bagley, Mark C; Davis, Terence; Dix, Matthew C; Murziani, Paola Gs; Rokicki, Michal J; Kipling, David

    2010-02-01

    The pyrazolyl ketone motif of RO3201195, which exhibits good oral bioavailability and high selectivity for p38 MAPK over other kinases, is a key pharmacophore that could find application in the treatment of Werner syndrome. Microwave irradiation promotes Knoevenagel condensation of a β-ketonitrile and formamidine, to give β-aminovinyl ketones, and their subsequent cyclocondensation with a subset of hydrazines to provide rapid access to a 24-membered library of pyrazolyl ketones. The library was evaluated in human hTERT-immortalized HCA2 dermal cells and Werner syndrome cells. Four compounds display comparable, if not slightly improved, potency over RO3201195.

  10. Sequential Aldol Condensation – Transition Metal-Catalyzed Addition Reactions of Aldehydes, Methyl Ketones and Arylboronic Acids

    PubMed Central

    Liao, Yuan-Xi; Xing, Chun-Hui; Israel, Matthew; Hu, Qiao-Sheng

    2011-01-01

    Sequential aldol condensation of aldehydes with methyl ketones followed by transition metal-catalyzed addition reactions of arylboronic acids to form β-substituted ketones is described. By using the 1,1′-spirobiindane-7,7′-diol (SPINOL)-based phosphite, an asymmetric version of this type of sequential reaction, with up to 92% ee, was also realized. Our study provided an efficient method to access β-substituted ketones and might lead to the development of other sequential/tandem reactions with transition metal-catalyzed addition reactions as the key step. PMID:21417359

  11. Sequential aldol condensation-transition metal-catalyzed addition reactions of aldehydes, methyl ketones, and arylboronic acids.

    PubMed

    Liao, Yuan-Xi; Xing, Chun-Hui; Israel, Matthew; Hu, Qiao-Sheng

    2011-04-15

    Sequential aldol condensation of aldehydes with methyl ketones followed by transition metal-catalyzed addition reactions of arylboronic acids to form β-substituted ketones is described. By using the 1,1'-spirobiindane-7,7'-diol (SPINOL)-based phosphite, an asymmetric version of this type of sequential reaction, with up to 92% ee, was also realized. Our study provided an efficient method to access β-substituted ketones and might lead to the development of other sequential/tandem reactions with transition metal-catalyzed addition reactions as the key step. © 2011 American Chemical Society

  12. 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

  13. Syn/anti isomerization of 2,4-dinitrophenylhydrazones in the determination of airborne unsymmetrical aldehydes and ketones using 2,4-dinitrophenylhydrazine derivation.

    PubMed

    Binding, N; Müller, W; Witting, U

    1996-10-01

    Aldehydes and ketones readily react with 2,4-dinitrophenylhydrazine (2,4-DNPH) to form the corresponding hydrazones. This reaction has been frequently used for the quantification of airborne carbonyl compounds. Since unsymmetrical aldehydes and ketones are known to form isomeric 2,4-dinitrophenylhydrazones (syn/ anti-isomers), the influence of isomerization on the practicability and accuracy of the 2,4-DNPH-method using 2,4-dinitrophenylhydrazine-coated solid sorbent samplers has been studied with three ketones (methyl ethyl ketone (MEK), methyl isopropyl ketone (MIPK), and methyl isobutyl ketone (MIBK)). With all three ketones the reaction with 2,4-DNPH resulted in mixtures of the isomeric hydrazones which were separated by HPLC and GC and identified by mass spectroscopy and (1)H nuclear magnetic resonance spectroscopy. The isomers show similar chromatographic behaviour in HPLC as well as in GC, thus leading to problems in quantification and interpretation of chromatographic results.

  14. 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

  15. Di(hydroxyphenyl)- benzimidazole monomers

    NASA Technical Reports Server (NTRS)

    Connell, John W. (Inventor); Hergenrother, Paul M. (Inventor); Smith, Joseph G. (Inventor)

    1993-01-01

    Di(hydroxyphenyl)benzimidazole monomers were prepared from phenyl-hydroxybenzoate and aromatic bis(o-diamine)s. These monomers were used in the synthesis of soluble polybenzimidazoles. The reaction involved the aromatic nucleophilic displacement of various di(hydroxyphenyl)benzimidazole monomers with activated aromatic dihalides or activated aromatic dinitro compounds in the presence of an alkali metal base. These polymers exhibited lower glass transition temperatures, improved solubility, and better compression moldability over their commercial counterparts.

  16. 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.

  17. 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.

  18. 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

  19. Raspberry ketone protects rats fed high-fat diets against nonalcoholic steatohepatitis.

    PubMed

    Wang, Lili; Meng, Xianjun; Zhang, Fengqing

    2012-05-01

    The protective effect of raspberry ketone against nonalcoholic steatohepatitis (NASH) was tested by using a high-fat diet-induced NASH model, and its mechanism was explored. Forty Sprague-Dawley rats with a 1:1 male to female ratio were randomly divided into five groups: the normal control (NC) group (n=8) fed normal diet for 8 weeks, the model control (MC) group (n=8) fed high-fat diet (82% standard diet, 8.3% yolk powder, 9.0% lard, 0.5% cholesterol, and 0.2% sodium taurocholate), and the raspberry ketone low-dose (0.5%) (RKL) group (n=8), the raspberry ketone middle-dose (1%) (RKM) group (n=8), and the raspberry ketone high-dose (2%) (RKH) group (n=8) fed high-fat diet for 4 weeks. After 8 weeks of experiment, all the rats were sacrificed, and blood lipid parameters (total cholesterol [TC], triglycerides [TG], high-density lipoprotein cholesterol [HDL-C], and low-density lipoprotein cholesterol [LDL-C]), liver function parameters (serum alanine aminotransferase [ALT], aspartate aminotransferase [AST], and alkaline phosphatase [ALP]), leptin (LEP), free fatty acid (FFA), tumor necrosis factor α (TNF-α), blood glucose (GLU), and insulin (INS) with calculated INS resistance index (IRI) and INS-sensitive index (ISI) were measured in rats. Therefore, we determined the peroxisome proliferator-activated receptor (PPAR)-α activity in liver homogenate and the levels of low-density lipoprotein receptor (LDLR), high-sensitivity C-reactive protein (hs-CRP), adiponection (APN), superoxide dismutase, and malondialdehyde (MDA). The liver tissues of rats in each group were imaged by electron microscopy with hematoxylin-eosin as the staining agent. The levels of TG, TC, LDL-C, ALT, AST, ALP, GLU, INS, IRI, FFA, LEP, TNF-α, MDA, and hs-CRP of MC rats were significantly increased (P<.05, P<.01). Therefore, the levels of HDL-C, ISI, PPAR-α, LDLR, and APN were significantly decreased (P<.05, P<.01). Compared with the MC group, each parameter in the RKL, RKM, and RKH groups was

  20. New reactions of germylenes with ketones and assessment of studio general chemistry

    NASA Astrophysics Data System (ADS)

    Sweeder, Ryan David

    New reaction modes of germylenes with ketones are presented. The germylene, Ge[CH(SiMe3)2]2 (1), will undergo reversible [4+2] addition with alkyl or aryl phenones to form a conjugated triene. Anthraquinone or 1,4-naphthylquinone will undergo a similar triene formation, but an insertion by a second molecule of 1 yields a product stable to reversion. In these cases, the second equivalent of germylene acts as a trap for the initially formed conjugated triene. A similar germylene, Ge[N(SiMe3)2]2 ( 2), reacts in analogous fashion with anthraquinone or 1,4-naphthylquinone indicating that it too engages in an equilibrium with phenones. The equilibrium for 2 with phenones lies heavily toward free 2 and phenone as no triene is detected via UV/Vis or NMR spectroscopies. Successful catalytic hydrogenation of the conjugate triene formed from the reaction of 1 with benzophenone is also presented. Other non-phenone ketones react with 1 via either CH or OH insertion. Three acetyl-containing ketones (acetone, butanone and cyclopropyl methyl ketone) have been observed to undergo CH insertion with 1 in the presence of one equivalent of MgCl2. The absence of MgCl 2 yields apparent OH insertion into the enol tautomer of the ketone. All secondary ketones examined undergo OH insertion even in the presence of MgCl2. The development, assessment and a description of a studio version of general chemistry are presented. This new course was implemented in the Fall 2002 semester at the University of Michigan. Content-based interviews focusing on equilibrium indicated that the students from the studio course had a better understanding of the underlying principles of equilibrium than their non-studio counterparts. The students enrolled in the studio course also gave more non-prompted explanations for a chemical reaction demonstrated during the interview, suggesting that they were more capable of transferring their chemical knowledge to new systems. The Motivated Strategies for Learning

  1. Oxaphospholes and Bisphospholes from Phosphinophosphonates and α,β-Unsaturated Ketones

    PubMed Central

    Arkhypchuk, Anna I; Orthaber, Andreas; Mihali, Viorica Alina; Ehlers, Andreas; Lammertsma, Koop; Ott, Sascha

    2013-01-01

    The reaction of a {W(CO)5}-stabilized phosphinophosphonate 1, (CO)5WPH(Ph)–P(O)(OEt)2, with ethynyl- (2 a–f) and diethynylketones (7–11, 18, and 19) in the presence of lithium diisopropylamide (LDA) is examined. Lithiated 1 undergoes nucleophilic attack in the Michael position of the acetylenic ketones, as long as this position is not sterically encumbered by bulky (iPr)3Si substituents. Reaction of all other monoacetylenic ketones with lithiated 1 results in the formation of 2,5-dihydro-1,2-oxaphospholes 3 and 4. When diacetylenic ketones are employed in the reaction, two very different product types can be isolated. If at least one (Me)3Si or (Et)3Si acetylene terminus is present, as in 7, 8, and 19, an anionic oxaphosphole intermediate can react further with a second equivalent of ketone to give cumulene-decorated oxaphospholes 14, 15, 24, and 25. Diacetylenic ketones 10 and 11, with two aromatic acetylene substituents, react with lithitated 1 to form exclusively ethenyl-bridged bisphospholes 16 and 17. Mechanisms that rationalize the formation of all heterocycles are presented and are supported by DFT calculations. Computational studies suggest that thermodynamic, as well as kinetic, considerations dictate the observed reactivity. The calculated reaction pathways reveal a number of almost isoenergetic intermediates that follow after ring opening of the initially formed oxadiphosphetane. Bisphosphole formation through a carbene intermediate G is greatly favored in the presence of phenyl substituents, whereas the formation of cumulene-decorated oxaphospholes is more exothermic for the trimethylsilyl-containing substrates. The pathway to the latter compounds contains a 1,3-shift of the group that stems from the acetylene terminus of the ketone substrates. For silyl substituents, the 1,3-shift proceeds along a smooth potential energy surface through a transition state that is characterized by a pentacoordinated silicon center. In contrast, a high

  2. Oxaphospholes and bisphospholes from phosphinophosphonates and α,β-unsaturated ketones.

    PubMed

    Arkhypchuk, Anna I; Orthaber, Andreas; Mihali, Viorica Alina; Ehlers, Andreas; Lammertsma, Koop; Ott, Sascha

    2013-10-04

    The reaction of a {W(CO)5 }-stabilized phosphinophosphonate 1, (CO)5 WPH(Ph)P(O)(OEt)2 , with ethynyl- (2 a-f) and diethynylketones (7-11, 18, and 19) in the presence of lithium diisopropylamide (LDA) is examined. Lithiated 1 undergoes nucleophilic attack in the Michael position of the acetylenic ketones, as long as this position is not sterically encumbered by bulky (iPr)3 Si substituents. Reaction of all other monoacetylenic ketones with lithiated 1 results in the formation of 2,5-dihydro-1,2-oxaphospholes 3 and 4. When diacetylenic ketones are employed in the reaction, two very different product types can be isolated. If at least one (Me)3 Si or (Et)3 Si acetylene terminus is present, as in 7, 8, and 19, an anionic oxaphosphole intermediate can react further with a second equivalent of ketone to give cumulene-decorated oxaphospholes 14, 15, 24, and 25. Diacetylenic ketones 10 and 11, with two aromatic acetylene substituents, react with lithitated 1 to form exclusively ethenyl-bridged bisphospholes 16 and 17. Mechanisms that rationalize the formation of all heterocycles are presented and are supported by DFT calculations. Computational studies suggest that thermodynamic, as well as kinetic, considerations dictate the observed reactivity. The calculated reaction pathways reveal a number of almost isoenergetic intermediates that follow after ring opening of the initially formed oxadiphosphetane. Bisphosphole formation through a carbene intermediate G is greatly favored in the presence of phenyl substituents, whereas the formation of cumulene-decorated oxaphospholes is more exothermic for the trimethylsilyl-containing substrates. The pathway to the latter compounds contains a 1,3-shift of the group that stems from the acetylene terminus of the ketone substrates. For silyl substituents, the 1,3-shift proceeds along a smooth potential energy surface through a transition state that is characterized by a pentacoordinated silicon center. In contrast, a high

  3. A reactive and sensitive diffusion sampler for the determination of aldehydes and ketones in ambient air

    NASA Astrophysics Data System (ADS)

    Uchiyama, Shigehisa; Hasegawa, Shuji

    We developed a diffusive sampling device (DSD-carbonyl) for organic carbonyl compounds (aldehydes and ketones) which is suitable for collection and analysis of low concentration levels. This sampling device is composed of three parts, an exposure part made of a porous polytetrafluoroethylene (PPTFE) tube, an analysis part made of polypropylene (PP) tubing and an absorbent part made of 2,4-dinitrophenylhydrazine (DNPH) coated silica gel (DNPH-silica). Aldehydes and ketones diffuse to the DSD-carbonyl through PPTFE-tube by the mechanism of molecular diffusion and react specifically with DNPH to form a stable DNPH-derivatives. Collection is controlled by moving the absorbent from the exposure part to the analysis part by changing the posture of the DSD-carbonyl. DNPH-derivatives were eluted from an analysis part of DSD-carbonyl with acetonitrile directly and analyzed by high performance liquid chromatography (HPLC). The advantages of the DSD-carbonyl are the following: (1) The DSD-carbonyl can be used in a wide range of concentration of aldehydes and ketones in atmosphere, as the DSD-carbonyl exposure part has a variable diffusion area, (2) DNPH-derivatives are eluted from DNPH-silica without contamination of air. (3) The sampler can be applied to active sampling by connecting it with a pump. The limit of detection (LOD) for concentrations of major aldehydes and ketones ranged from 0.072 to 0.13 ppb, and the limit of quantitation (LOQ) ranged from 0.24 to 0.42 ppb. The coefficient variation (CV) for concentrations of major aldehydes and ketones ranged from 2.5 to 3.0% in laboratory air. The DSD-carbonyl method and active sampling method (US EPA method IP-6A) showed a good correlation (formaldehyde, r2=0.995). The uptake rates for formaldehyde, acetaldehyde, and acetone were estimated as 0.078, 0.062 and 0.079 nmol ppb -1 h -1, respectively. It is possible to estimate atmospheric aldehydes and ketones at parts per billion (ppb), with high sensitivity and precision, by

  4. Alpha and beta thalassemia.

    PubMed

    Muncie, Herbert L; Campbell, James

    2009-08-15

    The thalassemias are a group of inherited hematologic disorders caused by defects in the synthesis of one or more of the hemoglobin chains. Alpha thalassemia is caused by reduced or absent synthesis of alpha globin chains, and beta thalassemia is caused by reduced or absent synthesis of beta globin chains. Imbalances of globin chains cause hemolysis and impair erythropoiesis. Silent carriers of alpha thalassemia and persons with alpha or beta thalassemia trait are asymptomatic and require no treatment. Alpha thalassemia intermedia, or hemoglobin H disease, causes hemolytic anemia. Alpha thalassemia major with hemoglobin Bart's usually results in fatal hydrops fetalis. Beta thalassemia major causes hemolytic anemia, poor growth, and skeletal abnormalities during infancy. Affected children will require regular lifelong blood transfusions. Beta thalassemia intermedia is less severe than beta thalassemia major and may require episodic blood transfusions. Transfusion-dependent patients will develop iron overload and require chelation therapy to remove the excess iron. Bone marrow transplants can be curative for some children with beta thalassemia major. Persons with thalassemia should be referred for preconception genetic counseling, and persons with alpha thalassemia trait should consider chorionic villus sampling to diagnose infants with hemoglobin Bart's, which increases the risk of toxemia and postpartum bleeding. Persons with the thalassemia trait have a normal life expectancy. Persons with beta thalassemia major often die from cardiac complications of iron overload by 30 years of age.

  5. MOON for neutrino-less {beta}{beta} decays and {beta}{beta} nuclear matrix elements

    SciTech Connect

    Ejiri, H.

    2009-11-09

    The MOON project aims at spectroscopic 0v{beta}{beta} studies with the v-mass sensitivity of 100-30 meV by measuring two beta rays from {sup 100}Mo and/or {sup 82}Se. The detector is a compact super-module of multi-layer PL scintillator plates. R and D works made by the pro to-type MOON-1 and the small PL plate show the possible energy resolution of around {sigma}{approx}2.2%, as required for the mass sensitivity. Nuclear matrix elements M{sup 2v} for 2v{beta}{beta} are shown to be given by the sum {sigma}{sub L}M{sub k} of the 2v{beta}{beta} matrix elements M{sub k} through intermediate quasi-particle states in the Fermi-surface, where Mi is obtained experimentally by using the GT(J{sup {pi}} = 1{sup +}) matrix elements of M{sub i}(k) and M{sub f}(k) for the successive single-{beta} transitions through the k-th intermediate state.

  6. Beta-Carotene

    USDA-ARS?s Scientific Manuscript database

    Beta-carotene is a pigment that occurs naturally in many photosynthetic plants and organisms and one of the most abundant carotenoids found in human blood. The richest dietary sources of beta-carotene are yellow, orange, and leafy green fruits and vegetables, such as carrots, spinach, sweet potatoes...

  7. Beta blockers in hypertension.

    PubMed

    Thadani, U

    1983-11-10

    Beta-adrenoceptor antagonists are effective in the management of patients with mild-to-moderate hypertension. Noncardioselective agents, cardioselective agents and beta blockers with intrinsic sympathomimetic activity (ISA) are equally effective, provided they are used in equipotent doses. Beta blockers can be used as first-line therapy in the management of hypertension and can be safely combined with diuretics, vasodilators, or both, for a better control of blood pressure. The exact mechanism by which beta blockers decrease blood pressure remains speculative, but they all reduce cardiac output during long-term therapy; drugs with ISA lower cardiac output and heart rate less than do drugs without ISA. Pharmacokinetic properties of beta blockers differ widely; drugs metabolized by the liver have shorter plasma half-lives than drugs primarily excreted by the kidneys. Although many of the side effects of various beta blockers are similar, differences in water and lipid solubility account for a higher incidence of central nervous system side effects with lipid-soluble drugs (such as propranolol and metoprolol) than with hydrophilic drugs (such as atenolol and timolol). The incidence of cold extremities has been reported to be less with drugs with ISA, and the incidence of bronchospasm less with cardioselective drugs. In the management of uncomplicated mild-to-moderate hypertension, all beta blockers are equally effective and produce less troublesome side effects than alternative antihypertensive agents. For effective therapy beta blockers can be used in 2 divided daily doses or even once daily.(ABSTRACT TRUNCATED AT 250 WORDS)

  8. A low-noise beta-radiometer

    SciTech Connect

    Antonenko, G.I.; Savina, V.I.

    1995-12-01

    The two-channel detector for a low-noise (down to 0.06 sec{sup -1}) beta-radiometer for measuring the mass concentration of {sup 90}Sr in the environment after the chemical extraction of strontium by the oxalate-nitrate method was certified at the D.I. Mendeleev Institute of Metrology (certificate No. 137/93). A detector unit using two end-window self-quenching counters with thin input windows (8 {mu}m thick and 60 mm in diameter) operating as a Geiger-Mueller counter and filled with a mixture of 90% helium (atomic gas) and 10% ethanol (organic molecules) can measure the beta-activity of two substrates concurrently. It is often used to detect the beta-radiation of {sup 90}Sr. This isotope produces particles with energies ranging from 180 to 1000 keV, and the detection efficiency is 50% at a level of 0.1 Bq after measuring for 20 min with an uncertainty of 25%.

  9. Luminescent Properties of Arylpolyene Organic Dyes and Cross-Conjugated Ketones Promising for Quantum Optics and Nanophotonics Applications

    NASA Astrophysics Data System (ADS)

    Naumova, N. L.; Vasilyeva, I. A.

    2015-09-01

    The spectral-luminescent properties of some dyes of substituted arylpolyenes and cross-conjugated ketones class in Shpolsky matrices, promising for using in solving quantum optics and nanophotonics, were studied.

  10. 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

  11. One-pot enantioselective formation of eight-membered rings from alkenyl Fischer carbene complexes and ketone enolates.

    PubMed

    Barluenga, José; Diéguez, Alejandro; Rodríguez, Félix; Flórez, Josefa; Fañanás, Francisco J

    2002-08-07

    Eight-membered carbocycles with up to five new stereogenic centers are enantioselectively obtained following a one-pot procedure that involves the coupling of three components: an alkenyl Fischer carbene complex, a ketone enolate, and allyl lithium.

  12. 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.

  13. Metal-Free Trifluoromethylation of Aromatic and Heteroaromatic Aldehydes and Ketones

    PubMed Central

    2015-01-01

    The ability to convert simple and common substrates into fluoroalkyl derivatives under mild conditions remains an important goal for medicinal and agricultural chemists. One representative example of a desirable transformation involves the conversion of aromatic and heteroaromatic ketones and aldehydes into aryl and heteroaryl β,β,β-trifluoroethylarenes and -heteroarenes. The traditional approach for this net transformation involves stoichiometric metals and/or multistep reaction sequences that consume excessive time, material, and labor resources while providing low yields of products. To complement these traditional strategies, we report a one-pot metal-free decarboxylative procedure for accessing β,β,β-trifluoroethylarenes and -heteroarenes from readily available ketones and aldehydes. This method features several benefits, including ease of operation, readily available reagents, mild reaction conditions, high functional-group compatibility, and scalability. PMID:25001876

  14. Indium-mediated regioselective synthesis of ketones from arylstannanes under solvent-free ultrasound irradiation.

    PubMed

    Lo Fiego, Marcos J; Badajoz, Mercedes A; Domini, Claudia; Chopa, Alicia B; Lockhart, María T

    2013-05-01

    The solvent-free indium-promoted reaction of alkanoyl chlorides with sterically and electronically diverse arylstannanes is a simple and direct method for the regioselective synthesis of primary, secondary and tertiary alkyl aryl ketones in good to excellent isolated yields (42-84%) under mild and neutral conditions. The protocol is also adequate for the synthesis of aryl vinyl ketones. Reaction times are drastically reduced (from 3-32h to 10-70min) under ultrasonic irradiation. Evidences for the involvement of a homolytic aromatic ipso-substitution mechanism, in which indium metal acts as radical initiator, are presented. It is possible the transference of two aryl groups from tin, thus improving effective mass yield, working with diarylstannanes as starting substrates. Copyright © 2012 Elsevier B.V. All rights reserved.

  15. Ketonization of enols in aqueous solution: is carbon protonation always rate-determining?

    PubMed

    Pelliccioli, Anna Paola; Šebej, Peter; Wirz, Jakob

    2012-06-01

    The pH-rate profiles for the ketonization of the (E)- and (Z)-photoenols of o-methylacetophenone (MA) in aqueous solution were determined by nanosecond laser flash photolysis. Carbon protonation of the enol anions of MA by solvent water is exceptionally fast, k(0)'(K)≈ 2.0 × 10(7) s(-1), too fast to permit establishment of the acid-base equilibrium on the enol oxygen prior to ketonization. Analysis of the pH-rate profile of the (E)-enol using the common assumption of rate-determining carbon protonation would lead to an erroneous value for the acidity constant of that enol, pK(a,c)(E) = 11.3, which is too high by about two pK units.

  16. Effects of 70-keV electrons on two polyarylene ether ketones

    NASA Technical Reports Server (NTRS)

    Kingsbury, Kevin B.; Hawkins, Douglas S.; Orwoll, Robert A.; Kiefer, Richard L.; Long, Sheila A. T.

    1989-01-01

    Films prepared from two polyarylene ether ketones with the repeat units -PhC(O)PhC(O)-PhOPhXPhO- where X = C(CH3)2 or CH2 and Ph = C6H4, were bombarded with 70-keV electrons. The effects of irradiation were determined from the fraction of gel formed; the intrinsic viscosities, gel permeation chromatography, and NMR spectroscopy of the soluble portion of the irradiated films; and the changes in the IR spectra of the materials. In a Charlesby-Pinner analysis of the gel fractions of the polyarylene ether ketone with the isopropylidene group, the numbers of scission and cross-linking events per 100 eV (9649 kJ/mol) absorbed were found to be small with G(S) = 0.002 and G(X) = 0.009, respectively.

  17. Nonpeptidic Tetrafluorophenoxymethyl Ketone Cruzain Inhibitors as Promising New Leads for Chagas Disease Chemotherapy†

    PubMed Central

    Brak, Katrien; Kerr, Iain D.; Barrett, Kimberly T.; Fuchi, Nobuhiro; Debnath, Moumita; Engel, Juan C.; McKerrow, James H.; Doyle, Patricia S.; Brinen, Linda S.; Ellman, Jonathan A.

    2010-01-01

    A century after discovering that the Trypanosoma cruzi parasite is the etiological agent of Chagas disease, treatment is still plagued by limited efficacy, toxicity, and the emergence of drug resistance. The development of inhibitors of the major T. cruzi cysteine protease, cruzain, has been demonstrated to be a promising drug discovery avenue for this neglected disease. Here we establish that a nonpeptidic tetrafluorophenoxymethyl ketone cruzain inhibitor substantially ameliorates symptoms of acute Chagas disease in a mouse model with no apparent toxicity. A high-resolution crystal structure confirmed the mode of inhibition and revealed key binding interactions of this novel inhibitor class. Subsequent structure-guided optimization then resulted in inhibitor analogs with improvements in potency despite minimal or no additions in molecular weight. Evaluation of the analogs in cell culture showed enhanced activity. These results suggest that nonpeptidic tetrafluorophenoxymethyl ketone cruzain inhibitors have the potential to fulfill the urgent need for improved Chagas disease chemotherapy. PMID:20088534

  18. Effects of 70-keV electrons on two polyarylene ether ketones

    NASA Technical Reports Server (NTRS)

    Kingsbury, Kevin B.; Hawkins, Douglas S.; Orwoll, Robert A.; Kiefer, Richard L.; Long, Sheila A. T.

    1989-01-01

    Films prepared from two polyarylene ether ketones with the repeat units -PhC(O)PhC(O)-PhOPhXPhO- where X = C(CH3)2 or CH2 and Ph = C6H4, were bombarded with 70-keV electrons. The effects of irradiation were determined from the fraction of gel formed; the intrinsic viscosities, gel permeation chromatography, and NMR spectroscopy of the soluble portion of the irradiated films; and the changes in the IR spectra of the materials. In a Charlesby-Pinner analysis of the gel fractions of the polyarylene ether ketone with the isopropylidene group, the numbers of scission and cross-linking events per 100 eV (9649 kJ/mol) absorbed were found to be small with G(S) = 0.002 and G(X) = 0.009, respectively.

  19. Electron attachment studies to musk ketone and high mass resolution anionic isobaric fragment detection

    NASA Astrophysics Data System (ADS)

    Mauracher, A.; Sulzer, P.; Alizadeh, E.; Denifl, S.; Ferreira da Silva, F.; Probst, M.; Märk, T. D.; Limão-Vieira, P.; Scheier, P.

    2008-11-01

    Gas phase electron attachment studies have been performed for musk ketone by means of a crossed electron-molecular beams experiment in an energy range from 0 to 15 eV with a resolution of ~70 meV. Additional measurements, utilizing a two-sector-field instrument, have been used to distinguish between possible isobaric products. Anion efficiency curves for 19 anions have been measured including a long-lived (metastable) non-dissociated parent anion which is formed at energies near 0 eV. Many of the dissociative electron attachment products observed at low energy arise from surprisingly complex reactions associated with multiple bond cleavages and structural and electronic rearrangement. The present results are compared with previous aromatic nitrocompounds studied in our laboratory recently. Particularly the close similarity of musk ketone and the explosive trinitrotoluene is of special interest.

  20. The inverse problem of brain energetics: ketone bodies as alternative substrates

    NASA Astrophysics Data System (ADS)

    Calvetti, D.; Occhipinti, R.; Somersalo, E.

    2008-07-01

    Little is known about brain energy metabolism under ketosis, although there is evidence that ketone bodies have a neuroprotective role in several neurological disorders. We investigate the inverse problem of estimating reaction fluxes and transport rates in the different cellular compartments of the brain, when the data amounts to a few measured arterial venous concentration differences. By using a recently developed methodology to perform Bayesian Flux Balance Analysis and a new five compartment model of the astrocyte-glutamatergic neuron cellular complex, we are able to identify the preferred biochemical pathways during shortage of glucose and in the presence of ketone bodies in the arterial blood. The analysis is performed in a minimally biased way, therefore revealing the potential of this methodology for hypothesis testing.