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Sample records for diols

  1. Rapid synthesis of macrocycles from diol precursors

    DEFF Research Database (Denmark)

    Wingstrand, Magnus; Madsen, Charlotte Marie; Clausen, Mads Hartvig

    2009-01-01

    A method for the formation of synthetic macrocycles with different ring sizes from diols is presented. Reacting a simple diol precursor with electrophilic reagents leads to a cyclic carbonate, sulfite or phosphate in a single step in 25-60% yield. Converting the cyclization precursor to a bis-ele...

  2. Iridium catalysed synthesis of piperazines from diols

    DEFF Research Database (Denmark)

    Nordstrøm, Lars Ulrik Rubæk; Madsen, Robert

    2007-01-01

    A green and atom-economical method has been developed for the synthesis of piperazines by cyclocondensation of diols and amines in aqueous media in the presence of a catalytic amount of [Cp*IrCl2]2....

  3. Kinetics and mechanism of the oxidation of some diols by ...

    Indian Academy of Sciences (India)

    Abstract. The kinetics of oxidation of five vicinal and four non-vicinal diols, and two of their monoethers by benzyltrimethylammonium tribromide (BTMAB) have been studied in 3:7 (v/v) acetic acid–water mixture. The vicinal diols yield the carbonyl compounds arising out of the glycol bond fission while the other diols give.

  4. New applications of the interaction between diols and boronic acids

    NARCIS (Netherlands)

    Duval, F.L.

    2015-01-01

    Florine Duval - New applications of the interaction between diols and boronic acids – Summary

    Chapter 1 introduces the theory and known applications of the interaction between boronic acids and diols, and explains the context of this thesis. Diagnosis of

  5. Synthesis and complexation characteristics of phenanthroline and bipyridine diols

    NARCIS (Netherlands)

    Koning, B.; Boer, J.W. de; Meetsma, A.; Kellogg, R.M.

    2004-01-01

    Neocuproine (2,9-dimethyl-1,10-phenanthroline) 1 was converted to achiral and chiral tetradentate phenanthroline diols 3a-c by addition to benzophenone, adamantanone and camphor, respectively. Analogously 6,6'-dimethyl-2,2'-bipyridine 2 was converted to diol 7a on base-induced addition to

  6. Selective discrimination of cyclodextrin diols using cyclic sulfates

    DEFF Research Database (Denmark)

    Petrillo, Marta; Marinescu, Lavinia; Rousseau, Cyril

    2009-01-01

    A method for selective monofunctionalition of readily available cyclodextrin diols (2(A-F),3(A-F),6(B,C,E,F)-hexadeca-O-benzyl-alpha-cyclodextrin and 2(A-G),3(A-G),6(B,C,E-G)-nonadeca-O-benzyl-beta-cyclodextrin) by regioselective nucleophilic opening of their cyclic sulfates is presented. Although...

  7. Determination of 3-Monochloropropane-1,2-diol and 2-Monochloropropane-1,3-diol (MCPD) Esters and Glycidyl Esters by Microwave Extraction in Different Foodstuffs.

    Science.gov (United States)

    Marc, Corinne; Drouard-Pascarel, Valérie; Rétho, Cécile; Janvion, Patrice; Saltron, Frédéric

    2016-06-01

    This paper describes a method for the determination of 3-monochloropropane-1,2-diol and 2-monochloropropane-1,3-diol (MCPD) esters and glycidyl esters in various foodstuffs, which are isolated using microwave extraction. The next step is based on alkaline-catalyzed ester cleavage. The released glycidol is transformed into monobromopropanediol (MBPD). All compounds are derivatized in free diols (MCPD and MBPD) with phenylboronic acid and analyzed by gas chromatography-mass spectrometry (GC-MS). The method was validated for oils with a limit of quantitation (LOQ) of 0.1 mg/kg, for chips and crisps with a LOQ of 0.02 mg/kg, and for infant formula with a LOQ of 0.0025 mg/L. Recoveries of each sample were controlled by standard addition on extracts before derivatization. Quantitation was performed by the addition of isotopically labeled glycidyl and 3-monochloropropane-1,2-diol (3-MCPD) esters.

  8. Design and Synthesis of 2-Alkylpyrimidine-4,6-diol and 6-Alkylpyridine-2,4-diol as Potent GPR84 Agonists.

    Science.gov (United States)

    Liu, Yang; Zhang, Qing; Chen, Lin-Hai; Yang, Hui; Lu, Wei; Xie, Xin; Nan, Fa-Jun

    2016-06-09

    A series of alkylpyrimidine-4,6-diol derivatives were designed and synthesized as novel GRP84 agonists based on a high-throughput screening (HTS) hit 1. 6-Nonylpyridine-2,4-diol was identified as the most potent agonist of GPR84 reported so far, with an EC50 of 0.189 nM. These novel GPR84 agonists will provide valuable tools for the study of the physiological functions of GPR84.

  9. Development of Long Chain Alkyl Diol δD as a Paleohydrological Proxy

    Science.gov (United States)

    Neary, A.; Russell, J. M.; Cordero, D.

    2017-12-01

    Understanding past hydroclimate is important to better understand and prepare for future climate changes. Past hydrological change is often studied through δD of lipid biomarkers preserved in sediment. Long chain alkyl diols are lipid biomarkers that are widely distributed in lake and marine sediments. These compounds are produced by certain species of diatoms and algae (Eustigmatophytes). Diol δD is expected to record relative precipitation and evaporation, and other lake surface processes. This would be a valuable addition to the repertoire of organic compounds used for hydrologic reconstruction, such as leaf waxes which record precipitation. While long chain alkyl diols present an opportunity to expand the range of compounds available for compound specific isotope analysis, studies of diol δD are scarce. This study aims to compare diol and leaf wax δD records from Lake Tanganyika spanning approximately the past 20 kyrs in order to elucidate the controlling factors on diol δD values and evaluate the effectiveness of such a record as a paleohydrological proxy. If viable, diol δD records could be used to gain a deeper understanding of past climates. δD leaf wax records have been previously measured in Lake Tanganyika cores (Tierney et al., 2008). This study measures δD of long chain alkyl diols from the same cores in order to compare records. Our current measurements show significant deviations of the diol record from the leaf wax record at times when large magnitude changes in the leaf wax record are occurring, such as a less pronounced Younger Dryas and a more gradual decrease in δD values after Heinrich 1 than the sudden shift expressed by the leaf wax record. In addition to generating a diol δD record through time at Lake Tanganyika, we have also measured diol δD in surface sediments from several east African lakes in order to examine the potential for a proxy calibration. A positive correlation between diol and lake water δD has been observed

  10. Regioselective Acylation of Diols and Triols: The Cyanide Effect.

    Science.gov (United States)

    Peng, Peng; Linseis, Michael; Winter, Rainer F; Schmidt, Richard R

    2016-05-11

    Central topics of carbohydrate chemistry embrace structural modifications of carbohydrates and oligosaccharide synthesis. Both require regioselectively protected building blocks that are mainly available via indirect multistep procedures. Hence, direct protection methods targeting a specific hydroxy group are demanded. Dual hydrogen bonding will eventually differentiate between differently positioned hydroxy groups. As cyanide is capable of various kinds of hydrogen bonding and as it is a quite strong sterically nondemanding base, regioselective O-acylations should be possible at low temperatures even at sterically congested positions, thus permitting formation and also isolation of the kinetic product. Indeed, 1,2-cis-diols, having an equatorial and an axial hydroxy group, benzoyl cyanide or acetyl cyanide as an acylating agent, and DMAP as a catalyst yield at -78 °C the thermodynamically unfavorable axial O-acylation product; acyl migration is not observed under these conditions. This phenomenon was substantiated with 3,4-O-unproteced galacto- and fucopyranosides and 2,3-O-unprotected mannopyranosides. Even for 3,4,6-O-unprotected galactopyranosides as triols, axial 4-O-acylation is appreciably faster than O-acylation of the primary 6-hydroxy group. The importance of hydrogen bonding for this unusual regioselectivity could be confirmed by NMR studies and DFT calculations, which indicate favorable hydrogen bonding of cyanide to the most acidic axial hydroxy group supported by hydrogen bonding of the equatorial hydroxy group to the axial oxygen. Thus, the "cyanide effect" is due to dual hydrogen bonding of the axial hydroxy group which enhances the nucleophilicity of the respective oxygen atom, permitting an even faster reaction for diols than for mono-ols. In contrast, fluoride as a counterion favors dual hydrogen bonding to both hydroxy groups leading to equatorial O-acylation.

  11. Preparation and biological characteristics of 99mTc-diol a renal agent

    International Nuclear Information System (INIS)

    Castanheira, I.; Paulo, A.; Neves, M.; Patricio, L.; Sawas-Dimopoulou, C.

    1993-01-01

    The present work concerns the production of 1,2-dihydroxypropyl-1-phosphonic acid (diol) by acid hydrolysis of (-cis) 1,2-epoxypropylphosphonic acid (phosphomycin), and its formation as a kit easily labeled with [ 99m Tc]pertechnetate. Biodistribution studies and whole-body autoradiographies in mice show that 99m Tc-diol has a specific affinity for the kidneys: it is rapidly cleared from the blood and excreted in urine. Part of the injected activity remains in the kidney cortex sufficiently long to permit kidney imaging. In comparison with other agents which also localize in the kidney cortex, such as 99m Tc-DMSA and 99m Tc-glucoheptonate ( 99m Tc-GHA), the main differences are the following: the peak of renal activity is reached early in the 5 min post-injection period for 99m Tc-diol, only at about 10 min post-injection for 99m Tc-GHA and after 3 h post-injection for 99m Tc-DMSA. The uptake of 99m Tc-diol by other organs, especially by bones, is much smaller than in the case of 99m Tc-DMSA. Unlike 99m Tc-DMSA, the biodistribution of 99m Tc-diol is not significantly influenced by acid-base imbalance. Moreover, the retention effect of hyperuricemia on 99m Tc-diol blood clearance and kidney excretion could be the result of a competition mechanism between this radiopharmaceutical and uric acid for a common transport system. The above biological characteristics suggest that 99m Tc-diol is a kidney radiopharmaceutical with an ability for functional and imaging studies. (author)

  12. The use of positron annihilation to study polyacrylamide and polymethylmethacrylate-Alcohols and diols mixture

    International Nuclear Information System (INIS)

    Mostafa, N.

    2007-01-01

    The effect of addition of both alcohols and diols to polyacrylamide (PAA) and polymethylmethacrylate (PMMA) forming polymer mixtures was studied using positron annihilation lifetime (PAL) and Doppler broadening of annihilation radiation (DBAR) techniques. It was found that, by increasing chain length of alcohols, PAA-alcohols contain free volume with small size V and low fraction f, while PMMA-alcohols contain free volume with large size and high fraction. On the other hand, S-parameter increases and W-parameter decreases in PAA-diols according to the number of carbon and hydrogen atoms in the chain. In addition, the electrical conductivity measurements are performed on the above two polymer mixtures. The results showed that both PAA and PMMA exhibit semiconducting properties by the addition of alcohols and diols. Correlation between the macroscopic conductivity properties and the microstructures such as free volume and microdefects are established

  13. Energy and chemicals from the selective electrooxidation of renewable diols by organometallic fuel cells.

    Science.gov (United States)

    Bellini, Marco; Bevilacqua, Manuela; Filippi, Jonathan; Lavacchi, Alessandro; Marchionni, Andrea; Miller, Hamish A; Oberhauser, Werner; Vizza, Francesco; Annen, Samuel P; Grützmacher, H

    2014-09-01

    Organometallic fuel cells catalyze the selective electrooxidation of renewable diols, simultaneously providing high power densities and chemicals of industrial importance. It is shown that the unique organometallic complex [Rh(OTf)(trop2NH)(PPh3)] employed as molecular active site in an anode of an OMFC selectively oxidizes a number of renewable diols, such as ethylene glycol , 1,2-propanediol (1,2-P), 1,3-propanediol (1,3-P), and 1,4-butanediol (1,4-B) to their corresponding mono-carboxylates. The electrochemical performance of this molecular catalyst is discussed, with the aim to achieve cogeneration of electricity and valuable chemicals in a highly selective electrooxidation from diol precursors. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Gas-phase water-mediated equilibrium between methylglyoxal and its geminal diol

    Science.gov (United States)

    Axson, Jessica L.; Takahashi, Kaito; De Haan, David O.; Vaida, Veronica

    2010-01-01

    In aqueous solution, aldehydes, and to a lesser extent ketones, hydrate to form geminal diols. We investigate the hydration of methylglyoxal (MG) in the gas phase, a process not previously considered to occur in water-restricted environments. In this study, we spectroscopically identified methylglyoxal diol (MGD) and obtained the gas-phase partial pressures of MG and MGD. These results, in conjunction with the relative humidity, were used to obtain the equilibrium constant, KP, for the water-mediated hydration of MG in the gas phase. The Gibbs free energy for this process, ΔG°, obtained as a result, suggests a larger than expected gas-phase diol concentration. This may have significant implications for understanding the role of organics in atmospheric chemistry. PMID:20142510

  15. Thermoresponsive Polymers and Inverse Opal Hydrogels for the Detection of Diols.

    Science.gov (United States)

    Couturier, Jean-Philippe; Wischerhoff, Erik; Bernin, Robert; Hettrich, Cornelia; Koetz, Joachim; Sütterlin, Martin; Tiersch, Brigitte; Laschewsky, André

    2016-05-03

    Responsive inverse opal hydrogels functionalized by boroxole moieties were synthesized and explored as sensor platforms for various low molar mass as well as polymeric diols and polyols, including saccharides, glycopolymers and catechols, by exploiting the diol induced modulation of their structural color. The underlying thermoresponsive water-soluble copolymers and hydrogels exhibit a coil-to-globule or volume phase transition, respectively, of the LCST-type. They were prepared from oligoethylene oxide methacrylate (macro)monomers and functionalized via copolymerization to bear benzoboroxole moieties. The resulting copolymers represent weak polyacids, which can bind specifically to diols within an appropriate pH window. Due to the resulting modulation of the overall hydrophilicity of the systems and the consequent shift of their phase transition temperature, the usefulness of such systems for indicating the presence of catechols, saccharides, and glycopolymers was studied, exploiting the diol/polyol induced shifts of the soluble polymers' cloud point, or the induced changes of the hydrogels' swelling. In particular, the increased acidity of benzoboroxoles compared to standard phenylboronic acids allowed performing the studies in PBS buffer (phosphate buffered saline) at the physiologically relevant pH of 7.4. The inverse opals constructed of these thermo- and analyte-responsive hydrogels enabled following the binding of specific diols by the induced shift of the optical stop band. Their highly porous structure enabled the facile and specific optical detection of not only low molar mass but also of high molar mass diol/polyol analytes such as glycopolymers. Accordingly, such thermoresponsive inverse opal systems functionalized with recognition units represent attractive and promising platforms for the facile sensing of even rather big analytes by simple optical means, or even by the bare eye.

  16. Sources and proxy potential of long chain alkyl diols in lacustrine environments

    Science.gov (United States)

    Rampen, Sebastiaan W.; Datema, Mariska; Rodrigo-Gámiz, Marta; Schouten, Stefan; Reichart, Gert-Jan; Sinninghe Damsté, Jaap S.

    2014-11-01

    Long chain 1,13- and 1,15-alkyl diols form the base of a number of recently proposed proxies used for climate reconstruction. However, the sources of these lipids and environmental controls on their distribution are still poorly constrained. We have analyzed the long chain alkyl diol (LCD) composition of cultures of ten eustigmatophyte species, with three species from different families grown at various temperatures, to identify the effect of species composition and growth temperature on the LCD distribution. The results were compared with the LCD distribution of sixty-two lake surface sediments, and with previously reported LCD distributions from marine environments. The different families within the Eustigmatophyceae show distinct LCD patterns, with the freshwater family Eustigmataceae most closely resembling LCD distributions in both marine and lake environments. Unlike the other two eustigmatophyte families analyzed (Monodopsidaceae and Goniochloridaceae), C28 and C30 1,13-alkyl diols and C30 and C32 1,15-alkyl diols are all relatively abundant in the family Eustigmataceae, while the mono-unsaturated C32 1,15-alkyl diol was below detection limit. In contrast to the marine environment, LCD distributions in lakes did not show a clear relationship with temperature. The Long chain Diol Index (LDI), a proxy previously proposed for sea surface temperature reconstruction, showed a relatively weak correlation (R2 = 0.33) with mean annual air temperature used as an approximation for annual mean surface temperature of the lakes. A much-improved correlation (R2 = 0.74, p-value cultures of the family Eustigmataceae, suggesting that algae belonging to this family have an important role as a source for LCDs in lacustrine environments, or, alternatively, that the main sources of LCDs are similarly affected by temperature as the Eustigmataceae. The results suggest that LCDs may have the potential to be applicable as a palaeotemperature proxy for lacustrine environments

  17. Anti-1,2-Diols via Ni-Catalyzed Reductive Coupling of Alkynes and α-Oxyaldehydes

    Science.gov (United States)

    Luanphaisarnnont, Torsak; Ndubaku, Chudi O.; Jamison, Timothy F.

    2008-01-01

    Ni-catalyzed reductive coupling of aryl alkynes (1) and enantiomerically enriched α-oxyaldehydes (2) afford differentiated anti-1,2-diols (3) with high diastereoselectivity and regioselectivity, despite the fact that the methoxymethyl (MOM) and para-methoxybenzyl (PMB) protective groups typically favor syn-1,2-diol formation in carbonyl addition reactions of this family of aldehydes. PMID:15987174

  18. Regioselective Benzoylation of Diols and Carbohydrates by Catalytic Amounts of Organobase.

    Science.gov (United States)

    Lu, Yuchao; Hou, Chenxi; Ren, Jingli; Xin, Xiaoting; Xu, Hengfu; Pei, Yuxin; Dong, Hai; Pei, Zhichao

    2016-05-17

    A novel metal-free organobase-catalyzed regioselective benzoylation of diols and carbohydrates has been developed. Treatment of diol and carbohydrate substrates with 1.1 equiv. of 1-benzoylimidazole and 0.2 equiv. of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) in MeCN under mild conditions resulted in highly regioselective benzoylation for the primary hydroxyl group. Importantly, compared to most commonly used protecting bulky groups for primary hydroxyl groups, the benzoyl protective group offers a new protection strategy.

  19. Iridium‐Catalyzed Condensation of Amines and Vicinal Diols to Substituted Piperazines

    DEFF Research Database (Denmark)

    Lorentz-Petersen, Linda Luise Reeh; Nordstrøm, Lars Ulrik Rubæk; Madsen, Robert

    2012-01-01

    is believed to involve dehydrogenation of the 1,2‐diol to the α‐hydroxy aldehyde, which condenses with the amine to form the α‐hydroxy imine. The latter rearranges to the corresponding α‐amino carbonyl compound, which then reacts with another amine followed by reduction of the resulting imine.......A straightforward procedure is described for the synthesis of piperazines from amines and 1,2‐diols. The heterocyclization is catalyzed by [Cp*IrCl2]2 and sodium hydrogen carbonate and can be achieved with either toluene or water as solvent. The transformation does not require any stoichiometric...

  20. Kinetics of phosphotungstic acid catalyzed oxidation of propan-1,3-diol and butan-1,4-diol by N-chlorosaccharin

    Directory of Open Access Journals (Sweden)

    Sanjay Kumar Singh

    2011-09-01

    Full Text Available The kinetic studies of N-chlorosaccharin (NCSA oxidation of propan-1,3-diol and butan-1,4-diol have been reported in presence of phophotungstic acid and in aqueous acetic acid medium. The reactions follow first-order in NCSA and one to zero order with respect to substrate and phosphotungstic acid. Increase in the concentration of added perchloric acid increases the rate of oxidation. A negative effect on the oxidation rate is observed for solvent whereas the ionic strength does not influence the rate of reaction. Addition of the reaction product, saccharin, exhibited retarding effect. Various activation parameters have been evaluated. The products of the reactions were identified as the corresponding aldehydes. A suitable scheme of mechanism consistent with the experimental results has been proposed.

  1. Enzymatic monoesterification of symmetric diols: restriction of molecular conformations influences selectivity.

    Science.gov (United States)

    Tomer, Sanjiv O; Soni, Hemant P

    2017-10-31

    We have experimentally demonstrated that by 'locking' the molecular conformation through the introduction of a double or triple bond in the center of a symmetric diol, enzymatic monoesterification can be achieved selectively. The enzyme Candida antarctica lipase B, generally used for the transesterification of diols, can be effectively used for the monoesterification of symmetrical diols in an unbuffered system also. By varying the chain length of a carboxylic acid moiety, we have established that optimum selectivity and efficiency can be achieved in the range of 4.8 to 5.0 pK a values. Selectivity can be improved up to 98.75% for a monoester in an overall 73% yield (mixture of a monoester and a diester) when but-2-yne-1,4-diol reacted with hexanoic acid. Water, a by-product, provides an interfacial environment for the enzyme to work in the organic reaction medium. The uniqueness of the reported monoesterification protocol is that it involves only the mechanical stirring of the reaction mixture at room temperature in the presence of the enzyme for 24 h. High percentage yield with selectivity for a monoester, easier product isolation and overall, environmental sustainability are added advantages. The synthesized monoesters are characterized by using HNMR and high resolution mass spectrometry (HRMS).

  2. Synthesis of enantiomerically pure thiocrown ethers derived from 1,1'-binaphthalene-2,2'-diol

    NARCIS (Netherlands)

    Stock, H. Thijs; Kellogg, Richard M.

    1996-01-01

    Synthetic methodology is given for the preparation of two different types of thiocrown ethers from optically pure 1,1'-binaphthalene-2,2'-diol (10). The conceptually simplest approach starts from optically pure 10 itself, which is alkylated (4 equiv of K2CO3 in DMF at 110 degrees C) with

  3. Thermoplastic poly(urethane urea)s from novel, bio-based amorphous polyester diols

    NARCIS (Netherlands)

    Tang, D.; Noordover, B.A.J.; Sablong, R.J.; Koning, C.E.

    2012-01-01

    In this study, two novel, bio-based, amorphous polyester diols, namely poly(1,2-dimethylethylene adipate) (PDMEA) and poly(1,2-dimethylethylene succinate) (PDMES) are used to prepare thermoplastic poly(urethane urea)s (TPUUs). Interestingly, the TPUUs based on PDMEA show similar thermal and

  4. 211At-Rh(16-S4-diol) complex as a precursor for astatine radiopharmaceuticals

    International Nuclear Information System (INIS)

    Pruszynski, M.; Bilewicz, A.

    2006-01-01

    211 At is one of the most promising radionuclides in α-radioimmunotherapy (α-RIT). Unfortunately, biomolecules labeled by direct electrophilic astatination are unstable due to the rapid loss of 211 At under both in vitro and in vivo conditions. The present paper describes the results of our studies on attaching At - to the rhodium(III) complex with thioether ligand: 1,5,9,13-etrathiacyclohexadecane-3,11-diol (16-S4-diol). Rh 3+ was chosen as a moderately soft metal cation which should form very strong bonds with soft At - anions, but first of all because of the kinetic inertness of low spin rhodium(III) d 6 complexes. The 16-S4-diol ligand was selected due to formation of stable complexes with Rh 3+ . The experiments related to optimization of the reaction conditions were performed with the 131 I, basing on a chemical similarity of I - to At - . The experiments with 211 At were then carried out under the conditions found optimal for I - . The preliminary results are promising, and indicate a possibility for astatination of biomolecules by using the 211 At-Rh(16-S4-diol) complex

  5. Microbial Stereoselective One-Step Conversion of Diols to Chiral Lactones in Yeast Cultures

    Directory of Open Access Journals (Sweden)

    Filip Boratyński

    2015-12-01

    Full Text Available It has been shown that whole cells of different strains of yeast catalyze stereoselective oxidation of meso diols to the corresponding chiral lactones. Among screening-scale experiments, Candida pelliculosa ZP22 was selected as the most effective biocatalyst for the oxidation of monocyclic diols 3a–b with respect to the ratio of high conversion to stereoselectivity. This strain was used in the preparative oxidation, affording enantiomerically-enriched isomers of lactones: (+-(3aR,7aS-cis-hexahydro-1(3H -isobenzofuranone (2a and (+-(3aS,4,7,7aR-cis-tetrahydro-1(3H-isobenzofuranone (2b. Scaling up the culture growth, as well as biotransformation conditions has been successfully accomplished. Among more bulky substrates, bicyclic diol 3d was totally converted into enantiomerically-pure exo-bridged (+-(3aR,4S,7R,7aS-cis-tetrahydro-4,7-methanoisobenzofuran -1(3H-one (2d by Yarrovia lipolytica AR71. Microbial oxidation of diol 3f by Candida sake AM908 and Rhodotorula rubra AM4 afforded optically-pure cis-3-butylhexahydro-1(3H -isobenzofuranone (2f, however with low conversion.

  6. One step synthesis of 6-oxo-cholestan-3β,5α-diol

    International Nuclear Information System (INIS)

    Voisin, Maud; Silvente-Poirot, Sandrine; Poirot, Marc

    2014-01-01

    Highlights: • Cholesterol-5,6-epoxides are metabolized into cholestane-3β,5α,6β-triol (CT) in cancer cells. • 6-Oxo-cholestan-3β,5α-diol (OCDO) is a putative metabolite of CT. • The one step syntheses of CT and OCDO from cholesterol are reported. • The one step syntheses of labelled CT and OCDO are reported. - Abstract: Cholesterol metabolism has been recently linked to cancer, highlighting the importance of the characterization of new metabolic pathways in the sterol series. One of these pathways is centered on cholesterol-5,6-epoxides (5,6-ECs). 5,6-ECs can either generate dendrogenin A, a tumor suppressor present in healthy mammalian tissues, or the carcinogenic cholestane-3β,5α,6β-triol (CT) and its putative metabolite 6-oxo-cholestan-3β,5α-diol (OCDO) in tumor cells. We are currently investigating the identification of the enzyme involved in OCDO biosynthesis, which would be highly facilitated by the use of commercially unavailable [ 14 C]-cholestane-3β,5α,6β-triol and [ 14 C]-6-oxo-cholestan-3β,5α-diol. In the present study we report the one-step synthesis of [ 14 C]-cholestane-3β,5α,6β-triol and [ 14 C]-6-oxo-cholestan-3β,5α-diol by oxidation of [ 14 C]-cholesterol with iodide metaperiodate (HIO 4 )

  7. An efficient hydrophilic interaction liquid chromatography separation of 7 phospholipid classes based on a diol column

    NARCIS (Netherlands)

    Zhu, C.; Dane, A.; Spijksma, G.; Wang, M.; Greef, J. van der; Luo, G.; Hankemeier, T.; Vreeken, R.J.

    2012-01-01

    A hydrophilic interaction liquid chromatography (HILIC) - ion trap mass spectrometry method was developed for separation of a wide range of phospholipids. A diol column which is often used with normal phase chromatography was adapted to separate different phospholipid classes in HILIC mode using a

  8. Interaction of model aryl- and alkyl-boronic acids and 1,2-diols in aqueous solution.

    Science.gov (United States)

    Marinaro, William A; Prankerd, Richard; Kinnari, Kaisa; Stella, Valentino J

    2015-04-01

    The goal of this work was to quantitate ester formation between alkyl and aryl boronic acids and vicinal-diols or 1,2-diols in aqueous solution. As used here, 1,2-diols includes polyols with one or more 1,2-diol pairs. Multiple techniques were used including apparent pKa shifts of the boronic acids using UV spectrophotometry (for aryl acids) and titration (for aryl and alkyl acids). Isothermal microcalorimetry was also used, with all reactions being enthalpically favored. For all the acids and 1,2-diols and the conditions studied, evidence only supported 1:1 ester formation. All the esters formed were found to be significantly more acidic, as Lewis acids, by 3-3.5 pKa units than the corresponding nonesterified boronic acid. The equilibrium constants for ester formation increased with increasing number of 1,2-diol pairs but stereochemistry may also play a role as sorbitol with five possible 1,2-diol pairs and five isomers (taking into account the stereochemistry of the alcohol groups) was twice as efficient at ester formation compared with mannitol, also with five possible 1,2-diol pairs but only three isomers. Alkyl boronic acids formed esters to a greater extent than aryl acids. Although some quantitative differences were seen between the various techniques used, rank ordering of the structure/reactivity was consistent. Formulation implications of ester formation between boronic acids and 1,2-diols are discussed. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

  9. Chiral 1,2- and 1,3-diol-functionalized chromophores as Lego building blocks for coupled structures.

    Science.gov (United States)

    Spange, Stefan; Hofmann, Katja; Walfort, Bernhard; Rüffer, Tobias; Lang, Heinrich

    2005-10-14

    Chiral nitroanilines containing 1,2- or 1,3-diol functionalities have been synthesized by nucleophilic aromatic substitution of fluoronitroanilines with 1-aminopropane-2,3-diols and 2-aminopropane-1,3-diol in the melt. X-ray structure analyses confirm retention of the configuration of the chiral center. The novel chromophores are suitable to link reversibly to various substituted arylboronic acids which allows the construction of new solvatochromic sensor molecules suitable to response to solvent and anion coordination by fluoride. The solvatochromism of the new compounds has been studied using the Kamlet-Taft LSE relationship.

  10. 4 Birds 1 Stone to Inhibit 5androstane-3alpha,17beta-diol Conversion to DHT

    Science.gov (United States)

    2016-09-01

    Award Number: W81XWH-15-1-0409 TITLE: 4 Birds 1 Stone to Inhibit 5androstane-3alpha,17beta-diol Conversion to DHT PRINCIPAL INVESTIGATOR...SUBTITLE 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-15-1-04094 Birds 1 Stone to Inhibit 5androstane-3alpha,17beta-diol Conversion to DHT 5c...testicular androgens, testosterone or dihydrotestosterone ( DHT ). Men diagnosed with advanced prostate cancer or failure potentially curative therapy are

  11. Isomerization of 2-butene-1,4-diol in aqueous solutions catalyzed by palladium(II) complexes

    Energy Technology Data Exchange (ETDEWEB)

    Kalabin, S.M.; Novikov, N.A.; Belov, A.P.

    1989-02-01

    The authors studied the isomerization of 2-butene-1,4-diol into 3-butene-1,2-diol at 18-25/degree/C. The concentrations of the diol and PdCl/sub 2/ were (1.0-5.0) /times/ 10/sup /minus/2/ mole/liter at 5-10-fold excess amounts of HCl and NaCl. These additives were used because of their inhibiting action on the oxidation of olefinic compounds. 3-Butene-1,2-diol was identified by /sup 1/H NMR method directly in the reaction solutions in which the reaction solutions in which the reactions in D/sub 2/O were carried out. It was found that palladium(II) complexes catalyze the isomerization of 2-butene-1,4-diol into 3-butene-1,2-diol. A mechanism is proposed for the reaction, which includes the intermediate formation of /eta//sup 3/-allyl complex of palladium with a coordinated hydroxyl group.

  12. One step synthesis of 6-oxo-cholestan-3β,5α-diol

    Energy Technology Data Exchange (ETDEWEB)

    Voisin, Maud; Silvente-Poirot, Sandrine; Poirot, Marc, E-mail: marc.poirot@inserm.fr

    2014-04-11

    Highlights: • Cholesterol-5,6-epoxides are metabolized into cholestane-3β,5α,6β-triol (CT) in cancer cells. • 6-Oxo-cholestan-3β,5α-diol (OCDO) is a putative metabolite of CT. • The one step syntheses of CT and OCDO from cholesterol are reported. • The one step syntheses of labelled CT and OCDO are reported. - Abstract: Cholesterol metabolism has been recently linked to cancer, highlighting the importance of the characterization of new metabolic pathways in the sterol series. One of these pathways is centered on cholesterol-5,6-epoxides (5,6-ECs). 5,6-ECs can either generate dendrogenin A, a tumor suppressor present in healthy mammalian tissues, or the carcinogenic cholestane-3β,5α,6β-triol (CT) and its putative metabolite 6-oxo-cholestan-3β,5α-diol (OCDO) in tumor cells. We are currently investigating the identification of the enzyme involved in OCDO biosynthesis, which would be highly facilitated by the use of commercially unavailable [{sup 14}C]-cholestane-3β,5α,6β-triol and [{sup 14}C]-6-oxo-cholestan-3β,5α-diol. In the present study we report the one-step synthesis of [{sup 14}C]-cholestane-3β,5α,6β-triol and [{sup 14}C]-6-oxo-cholestan-3β,5α-diol by oxidation of [{sup 14}C]-cholesterol with iodide metaperiodate (HIO{sub 4})

  13. Mesogenic polybuthadiene diols with thiol side-chain units: synthesis and thermal behaviour

    Czech Academy of Sciences Publication Activity Database

    Bubnov, Alexej; Kašpar, Miroslav; Sedláková, Zdeňka

    2010-01-01

    Roč. 83, č. 1 (2010), 16-27 ISSN 0141-1594 R&D Projects: GA AV ČR IAA100100911; GA AV ČR(CZ) GA202/09/0047; GA MŠk OC 175 Institutional research plan: CEZ:AV0Z10100520; CEZ:AV0Z40500505 Keywords : mesogenic polymer * phase transition * polybutadiene diol * side -chain polymer Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.006, year: 2010

  14. Crystallization of DNA fragments from water-salt solutions, containing 2-methylpentane-2,3-diol.

    Science.gov (United States)

    Osica, V D; Sukharevsky, B Y; Vasilchenko, V N; Verkin, B I; Polyvtsev, O F

    1976-09-01

    Fragments of calf thymus DNA have been crystallized by precipitation from water-salt solutions, containing 2-methylpentane-2,3-diol (MPD). DNA crystals usually take the form either of spherulites up to 100 mu in diameter or of needles with the length up to 50 mu. No irreversible denaturation of DNA occurs during the crystallization process. X-ray diffraction from dense slurries of DNA crystals yields crystalline powder patterns.

  15. Approches synthétiques vers le mycothiazole-4,19-diol : utilisation du palladium en synthèse organique

    OpenAIRE

    Batt , Frédéric

    2009-01-01

    Mycothiazole-4,19-diol is a natural compound isolated in 2006 from a marine sponge cacospongia mycofijiensis which has never been synthesized. Its unique structure, its weak abundance and its potential biological activity make mycothiazole-4,19-diol an attractive target in organic chemistry. The challenge is the building of allylic diol-1,2 moiety. In order to make a concise and elegant synthesis of this molecule, four disconnections and many approaches have been studied. A study about the us...

  16. In vitro metabolism of benzo[a]pyrene-7,8-dihydrodiol and dibenzo[def,p]chrysene-11,12 diol in rodent and human hepatic microsomes

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Jordan N.; Mehinagic, Denis; Nag, Subhasree; Crowell, Susan R.; Corley, Richard A.

    2017-03-01

    Polycyclic aromatic hydrocarbons (PAHs) are contaminants that are ubiquitously found in the environment, produced through combustion of organic matter or petrochemicals, and many of which are procarcinogens. The prototypic PAH, benzo[a]pyrene (B[a]P) and the highly carcinogenic dibenzo[def,p]chrysene (DBC) are metabolically activated by isoforms of the P450 enzyme superfamily producing benzo[a]pyrene-7,8-dihydrodiol (B[a]P diol), dibenzo[def,p]chrysene-11,12 diol (DBC diol). Each of these diols can be further metabolized by cytochrome P450 enzymes to highly reactive diol-epoxide metabolites that readily react with DNA or by phase II conjugation facilitating excretion. To complement prior in vitro metabolism studies with parent B[a]P and DBC, both phase I metabolism and phase II glucuronidation of B[a]P diol and DBC diol were measured in hepatic microsomes from female B6129SF1/J mice, male Sprague-Dawley rats, and female humans. Metabolic parameters, including intrinsic clearance and Michaelis-Menten kinetics were calculated from substrate depletion data. Mice and rats demonstrated similar B[a]P diol phase I metabolic rates. Compared to rodents, human phase I metabolism of B[a]P diol demonstrated lower overall metabolic capacity, lower intrinsic clearance at higher substrate concentrations (>0.14 µM), and higher intrinsic clearance at lower substrate concentrations (<0.07 µM). Rates of DBC diol metabolism did not saturate in mice or humans and were highest overall in mice. Higher affinity constants and lower capacities were observed for DBC diol glucuronidation compared to B[a]P diol glucuronidation; however, intrinsic clearance values for these compounds were consistent within each species. Kinetic parameters reported here will be used to extend physiologically based pharmacokinetic (PBPK) models to include the disposition of B[a]P and DBC metabolites in animal models and humans to support future human health risk assessments.

  17. Aqueous benzene-diols react with an organic triplet excited state and hydroxyl radical to form secondary organic aerosol.

    Science.gov (United States)

    Smith, Jeremy D; Kinney, Haley; Anastasio, Cort

    2015-04-21

    Chemical processing in atmospheric aqueous phases, such as cloud and fog drops, can play a significant role in the production and evolution of secondary organic aerosol (SOA). In this work we examine aqueous SOA production via the oxidation of benzene-diols (dihydroxy-benzenes) by the triplet excited state of 3,4-dimethoxybenzaldehyde, (3)DMB*, and by hydroxyl radical, ˙OH. Reactions of the three benzene-diols (catechol (CAT), resorcinol (RES) and hydroquinone (HQ)) with (3)DMB* or ˙OH proceed rapidly, with rate constants near diffusion-controlled values. The two oxidants exhibit different behaviors with pH, with rate constants for (3)DMB* increasing as pH decreases from pH 5 to 2, while rate constants with ˙OH decrease in more acidic solutions. Mass yields of SOA were near 100% for all three benzene-diols with both oxidants. We also examined the reactivity of atmospherically relevant mixtures of phenols and benzene-diols in the presence of (3)DMB*. We find that the kinetics of phenol and benzene-diol loss, and the production of SOA mass, in mixtures are generally consistent with rate constants determined in experiments containing a single phenol or benzene-diol. Combining our aqueous kinetic and SOA mass yield data with previously published gas-phase data, we estimate a total SOA production rate from benzene-diol oxidation in a foggy area with significant wood combustion to be nearly 0.6 μg mair(-3) h(-1), with approximately half from the aqueous oxidation of resorcinol and hydroquinone, and half from the gas-phase oxidation of catechol.

  18. Solubility and thermodynamic behavior of vanillin in propane-1,2-diol+water cosolvent mixtures at different temperatures.

    Science.gov (United States)

    Shakeel, Faiyaz; Haq, Nazrul; Siddiqui, Nasir A; Alanazi, Fars K; Alsarra, Ibrahim A

    2015-12-01

    The solubilities of bioactive compound vanillin were measured in various propane-1,2-diol+water cosolvent mixtures at T=(298-318)K and p=0.1 MPa. The experimental solubility of crystalline vanillin was determined and correlated with calculated solubility. The results showed good correlation of experimental solubilities of crystalline vanillin with calculated ones. The mole fraction solubility of crystalline vanillin was recorded highest in pure propane-1,2-diol (7.06×10(-2) at 298 K) and lowest in pure water (1.25×10(-3) at 298 K) over the entire temperature range investigated. Thermodynamic behavior of vanillin in various propane-1,2-diol+water cosolvent mixtures was evaluated by Van't Hoff and Krug analysis. The results showed an endothermic, spontaneous and an entropy-driven dissolution of crystalline vanillin in all propane-1,2-diol+water cosolvent mixtures. Based on solubility data of this work, vanillin has been considered as soluble in water and freely soluble in propane-1,2-diol. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Zirconium-doped magnetic microspheres for the selective enrichment of cis-diol-containing ribonucleosides.

    Science.gov (United States)

    Fan, Hua; Chen, Peihong; Wang, Chaozhan; Wei, Yinmao

    2016-05-27

    Zirconium-doped magnetic microspheres (Zr-Fe3O4) for the selective enrichment of cis-diol-containing biomolecules were easily synthesized via a one-step hydrothermal method. Characterization of the microspheres revealed that zirconium was successfully doped into the lattice of Fe3O4 at a doping level of 4.0 at%. Zr-Fe3O4 possessed good magnetic properties and high specificity towards cis-diol molecules, as shown using 28 compounds. For ribonucleosides, the adsorbent not only has favorable anti-interferential abilities but also has a high adsorption capacity up to 159.4μmol/g. As an example of a real application, four ribonucleosides in urine were efficiently enriched and detected via magnetic solid-phase extraction coupled with high-performance liquid chromatography. Under the optimized extraction conditions, the detection limits were determined to be between 0.005 and 0.017μg/mL, and the linearities ranged from 0.02 to 5.00μg/mL (R≥0.996) for these analytes. The accuracy of the analytical method was examined by studying the relative recoveries of the analytes in real urine samples, with recoveries varying from 77.8% to 119.6% (RSDs<10.6%, n=6). The results indicate that Zr-Fe3O4 is a suitable adsorbent for the analysis of cis-diol-containing biomolecules in practical applications. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Ultrasonicated Synthesis of N-Benzyl-2,3-substituted Morpholines, via the Mitsunobu Diol Cyclisation

    Directory of Open Access Journals (Sweden)

    B. Jayachandra Reddy

    2010-01-01

    Full Text Available A facile five step synthesis of N-benzyl-2,3-substituted morpholines (i-iii was performed. The key steps were microwave assisted Friedel-crafts acylation and diol cyclization carried out via an ultra sonication of Mitsunobu reaction using DEAD (diethylazodicarboxylate, TPP in THF for 1 h. The morpholine products were generated as diasteriomers (ii andiii which has been separated by the column chromatography to good yield. The structure of compounds (i-iii has been characterized by the spectral and chemical studies.

  1. Synthesis of tritium labeled 4-androstenedione, 4-androsten 3α and 3β diols

    International Nuclear Information System (INIS)

    Matei, Lidia; Postolache, C.; Chiper, Diana; Tuta, C.; Bubueanu, G; Tanase, C.

    2009-01-01

    Androgen dependent diseases can appear due to blocking in different stages of biosynthesis of sexual hormones (testosterone, dihydrotestosterone) or to some modification in signalizing pathways through androgen receptor. In the diagnosis of these diseases which appear both in men and women (polycystic ovaries, hirsutism) it is also important the enzymatic activity determination of some key enzymes in steroid genesis steroid 5α-reductase, 3α and 3β-hydroxy-steroid-dehydrogenase, 17β- hydroxy-steroid-dehydrogenase. In this paper, we describe the method of obtaining tritium labeled 4-androstenedione, 4-androsten 3α and 3β diols by biosynthesis and chemical synthesis with testosterone used as substrate. (authors)

  2. Correlation analysis of reactivity in the oxidation of some organic diols by tripropylammonium fluorochromate in non-aqueous media

    Directory of Open Access Journals (Sweden)

    S. Sheik Mansoor

    2016-09-01

    Full Text Available The kinetics of oxidation of some organic diols by tripropylammonium fluorochromate (TriPAFC have been studied in dimethylsulfoxide (DMSO. The main product of oxidation is the corresponding hydroxy aldehydes. The reaction is first order with respect to TriPAFC and exhibited Michaelis-Menten type kinetics with respect to organic diols. The reaction is catalyzed by hydrogen ions. The hydrogen ion dependence has the form: kobs = a + b[H+]. Various thermodynamic parameters for the oxidation have been reported and discussed along with the validity of isokinetic relationship. Oxidation of diols was studied in 18 different organic solvents. The rate data are showing satisfactory correlation with Kamlet–Taft solvotochromic parameters (α, β and π∗. A suitable mechanism of oxidation has been proposed.

  3. Impact of culturing conditions on the abundance and composition of long chain alkyl diols in species of the genus

    NARCIS (Netherlands)

    Balzano, S.; Villanueva, L.; de Bar, M.; Sinninghe Damsté, J.S.; Schouten, S.

    2017-01-01

    Long chain alkyl diols (LCDs) are widespread in sediments and are synthesized, among others, by microalgae of the genus Nannochloropsis. The factors regulating the synthesis of LCDs and their biological function are, however, unclear. We investigated the changes in abundance of free + ester-bound

  4. Benzo(a)pyrene diol epoxides as intermediates in nucleic acid binding in vivo and in vitro

    DEFF Research Database (Denmark)

    Weinstein, I.B.; Jeffrey, A.M.; Jennette, K.W.

    1976-01-01

    Evidence has been obtained that a specific isomer of a diol epoxide derivative of benzo(a)pyrene, (+/-)-7 beta,8alpha-dihydroxy-9alpha, 10alpha-epoxy-7,8,9,10-tetrahydrobenzo(a)pyrene, is an intermediate in the binding of benzo(a)pyrene to RNA in cultured bovine bronchial mucosa. An adduct is for...

  5. Ruthenium-catalysed synthesis of 2- and 3-substituted quinolines from anilines and 1,3-diols

    DEFF Research Database (Denmark)

    Monrad, Rune Nygaard; Madsen, Robert

    2011-01-01

    A straightforward synthesis of substituted quinolines is described by cyclocondensation of anilines with 1,3-diols. The reaction proceeds in mesitylene solution with catalytic amounts of RuCl3·xH 2O, PBu3 and MgBr2·OEt2. The transformation does not require any stoichiometric additives and only...

  6. Femtosecond double proton transfer dynamics in [2,2'-bipyridyl]-3,3'-diol in sol-gel glasses

    NARCIS (Netherlands)

    Prosposito, P.; Marks, D.R.A.; Zhang, H.; Glasbeek, M.

    1998-01-01

    Abstract: Intramolecular excited state double proton-transfer dynamics has been studied for [2,2'-bipyridyl]-3,3'-diol (BP(OH)2) in sol-gel glass. By means of the femtosecond fluorescence up-conversion technique, the spectral dependence of the fluorescence transients obtained for BP(OH)2 in a few

  7. The introduction of a double bond on the steroid skeleton - the preparation of enol silyl ether derivatives from vicinal diols

    Czech Academy of Sciences Publication Activity Database

    Marek, Aleš; Klepetářová, Blanka; Elbert, Tomáš

    2011-01-01

    Roč. 76, č. 5 (2011), s. 443-456 ISSN 0010-0765 R&D Projects: GA AV ČR IAA400550801 Institutional research plan: CEZ:AV0Z40550506 Keywords : enol silyl ether * vicinal diol * steroids Subject RIV: CC - Organic Chemistry Impact factor: 1.283, year: 2011

  8. Facile and Highly Diastereoselective Synthesis of syn- and cis-1,2-Diol Derivatives from Protected alpha-Hydroxy Ketones

    Czech Academy of Sciences Publication Activity Database

    Jahn, Emanuela; Smrček, Jakub; Pohl, Radek; Císařová, I.; Jones, P. G.; Jahn, Ullrich

    2015-01-01

    Roč. 2015, č. 35 (2015), s. 7785-7798 ISSN 1434-193X Grant - others:COST(XE) CM1201 Institutional support: RVO:61388963 Keywords : synthetic methods * reduction * diastereoselectivity * diols * ketones Subject RIV: CC - Organic Chemistry Impact factor: 3.068, year: 2015

  9. Further characterization of benzo[a]pyrene diol-epoxide (BPDE)-induced comet assay effects.

    Science.gov (United States)

    Bausinger, Julia; Schütz, Petra; Piberger, Ann Liza; Speit, Günter

    2016-03-01

    The present study aims to further characterize benzo[a]pyrene diol-epoxide (BPDE)-induced comet assay effects. Therefore, we measured DNA effects by the comet assay and adduct levels by high-performance liquid chromatography (HPLC) in human lymphocytes and A549 cells exposed to (±)-anti-benzo[a]pyrene-7,8-diol 9,10-epoxide [(±)-anti-BPDE] or (+)-anti-benzo[a]pyrene-7,8-diol 9,10-epoxide [(+)-anti-BPDE]. Both, the racemic form and (+)-anti-BPDE, which is the most relevant metabolite with regard to mutagenicity and carcinogenicity, induced DNA migration in cultured lymphocytes in the same range of concentrations to a similar extent in the alkaline comet assay after exposure for 2h. Nevertheless, (+)-anti-BPDE induced significantly enhanced DNA migration after 16 and 18h post-cultivation which was not seen in response to (±)-anti-BPDE. Combination of the comet assay with the Fpg (formamidopyrimidine-DNA glycosylase) protein did not enhance BPDE-induced effects and thus indicated the absence of Fpg-sensitive sites (oxidized purines, N7-guanine adducts, AP-sites). The aphidicolin (APC)-modified comet assay suggested significant excision repair activity of cultured lymphocytes during the first 18h of culture after a 2 h-exposure to BPDE. In contrast to these repair-related effects measured by the comet assay, HPLC analysis of stable adducts did not reveal any significant removal of (+)-anti-BPDE-induced adducts from lymphocytes during the first 22h of culture. On the other hand, HPLC measurements indicated that A549 cells repaired about 70% of (+)-anti-BPDE-induced DNA-adducts within 22h of release. However, various experiments with the APC-modified comet assay did not indicate significant repair activity during this period in A549 cells. The conflicting results obtained with the comet assay and the HPLC-based adduct analysis question the real cause for BPDE-induced DNA migration in the comet assay and the reliability of the APC-modified comet assay for the

  10. ARA-aldehyde and ABA-trans-diol in apple fruits

    International Nuclear Information System (INIS)

    Rock, C.D.; Zeevaart, J.A.D.

    1989-01-01

    We have isolated ABA-aldehyde and ABA-t-diol from postharvest apple fruits, cv. Granny Smith and confirmed their structure by GC-MS. These putative ABA biosynthetic precursors incorporate 18 O to a similar degree as ABA during 48 hours under 18 O 2 atmospheres. The presence of significant amounts of ABA-aldehyde can explain the unique 18 O labeling pattern of ABA in this tissue, where a majority of ABA molecules containing 18 O is labeled in the 1'-hydroxyl group and not in the side chain carboxyl group, the primary site of incorporation for stressed leaves. Exchange of the carbonyl oxygen of ABA-aldehyde with water would decrease 18 O enrichment in the side chain. Results of 18 O 2 experiments and feeding studies using hexadeutero-ABA-aldehyde will be presented and the biosynthetic relationship of these compounds discussed

  11. [BMIM][PF(6)] promotes the synthesis of halohydrin esters from diols using potassium halides.

    Science.gov (United States)

    Oromí-Farrús, Mireia; Eras, Jordi; Villorbina, Gemma; Torres, Mercè; Llopis-Mestre, Veronica; Welton, Tom; Canela, Ramon

    2008-10-01

    Haloesterification of diverse diols with various carboxylic acids was achieved using potassium halides (KX) as the only halide source in ionic liquids. The best yield was obtained in [BMIM][PF(6)] when 1,2-octanediol, palmitic acid and KBr were used. This yield was 85% and the regioisomer with the bromine in primary position was present in a 75:25 ratio. The regioisomeric ratio could be improved using either KCl or some phenylcarboxylic acids. [BMIM][PF(6)] acts as both reaction media and catalyst of the reaction. To the best of our knowledge, this type of combined reaction using an ionic liquid is unprecedented. The other solvents tested did not lead either to the same yield or to the same regioisomeric ratio.

  12. Long chain diol index (LDI) as an organic-based sea surface temperature proxy in the Korean East Sea (NW Pacific)

    Science.gov (United States)

    Gal, Jong-Ku; Kim, Jung-Hyun; Kang, Su-Jin; Lee, Dong-Hun; Shin, Kyung-Hoon

    2016-04-01

    Long chain diol index (LDI) was introduced as an organic-based sea surface temperature (SST) proxy. LDI is expressed as the C30 1,15-diol abundance relative to those of C28 1,13-, C30 1,13- and C30 1,15-diols. There were a few studies which accessed the potential of LDI based on the culture, core top sediments, suspended particulate organic matters, and down-core sediments. However it is still unknown about the source of the diols and robustness as the SST proxy in the various marine environments. In the current study, we examined the applicability of the LDI in the East Sea of Korea where productivity and thus sedimentation rates are high. We will compare the LDI data with those of alkenone-based UK'37 by analyzing two multicores covering the last 100 year.

  13. Preparation and characterization of fluorophenylboronic acid-functionalized affinity monolithic columns for the selective enrichment of cis-diol-containing biomolecules.

    Science.gov (United States)

    Li, Qianjin; Liu, Zhen

    2015-01-01

    Boronate affinity monolithic columns have been developed into an important means for the selective recognition and capture of cis-diol-containing biomolecules, such as glycoproteins, nucleosides and saccharides. The ligands of boronic acids are playing an important role in boronate affinity monolithic columns. Although several boronate affinity monoliths with high affinity toward cis-diol-containing biomolecules have been reported, only few publications are focused on their detailed procedures for preparation and characterization. This chapter describes in detail the preparation and characterization of a boronate affinity monolithic column applying 2,4-difluoro-3-formyl-phenylboronic acid (DFFPBA) as a ligand. The DFFPBA-functionalized monolithic column not only exhibited an ultrahigh boronate affinity toward cis-diol-containing biomolecules, but also showed great potential for the selective enrichment of cis-diol-containing biomolecules in real samples.

  14. QSPR models based on molecular mechanics and quantum chemical calculations. 1. Construction of Boltzmann averaged descriptors for alkanes, alcohols, diols, ethers and cyclic compounds

    DEFF Research Database (Denmark)

    Dyekjær, Jane Dannow; Rasmussen, Kjeld; Jonsdottir, Svava Osk

    2002-01-01

    Values for nine descriptors for QSPR (quantitative structure-property relationships) modeling of physical properties of 96 alkanes, alcohols, ethers, diols, triols and cyclic alkanes and alcohols in conjunction with the program Codessa are presented. The descriptors are Boltzmann-averaged by sele......Values for nine descriptors for QSPR (quantitative structure-property relationships) modeling of physical properties of 96 alkanes, alcohols, ethers, diols, triols and cyclic alkanes and alcohols in conjunction with the program Codessa are presented. The descriptors are Boltzmann...

  15. Cs2CO3-promoted polycondensation of CO2with diols and dihalides for the synthesis of miscellaneous polycarbonates

    KAUST Repository

    Chen, Zuliang

    2016-07-12

    A one-pot protocol for the direct synthesis of polycarbonates through polycondensation of diols, dihalides and CO2 in the presence of Cs2CO3 is described. The conditions were optimized by studying the polycondensation of CO2 with 1,4-phenylenedimethanol and 1,4-dibromobutane as model monomers. Then, diols and dihalides with different spacers between the reactive groups including aliphatic, aromatic and poly(ethylene glycol) were tested under optimal conditions. Miscellaneous polycarbonates exhibiting molar masses in the range of 43 000 g mol-1 (GPC) and conversion higher than 96% could be obtained. The proposed mechanism rules out the possibility of ether linkage formation during polycondensation and accounts for the creation of carbonate linkages in two different ways. The thermal properties of the synthesized polycarbonates were unveiled by differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). © 2016 The Royal Society of Chemistry.

  16. Efficient Pd@MIL-101(Cr) hetero-catalysts for 2-butyne-1,4-diol hydrogenation exhibiting high selectivity

    KAUST Repository

    Yin, Dongdong

    2017-01-05

    Pd@MIL-101(Cr) hetero-catalysts have been successfully prepared using the metal-organic chemical vapour deposition (MOCVD) approach, by choosing [Pd(η-CH)(η-CH)] as a volatile precursor, and the hydrothermally stable metal-organic framework, MIL-101(Cr) as a support. The prepared Pd@MIL-101(Cr) hetero-catalysts characterized with various analytical techniques, exhibited highly monodispersed immobilized Pd nanoparticles in the MIL-101(Cr) cavities, while retaining the pristine crystallinity and porosity. The intact hybrid Pd@MIL-101(Cr) has been demonstrated to be an efficient catalyst for 2-butyne-1,4-diol hydrogenation with excellent activity, stability and selectivity (2-butene-1,4-diol (>94%)).

  17. Effects of the Amount and Type of Diol Ring Openers on the Properties of Oligolactide Acrylates for UV-Curable Printing Inks

    Directory of Open Access Journals (Sweden)

    Santi Kulsiriswad

    2017-10-01

    Full Text Available This study aimed to synthesize low viscosity oligolactide acrylates for UV-curable inks from oligolactide diols. Firstly, low molecular weight oligolactide diols were prepared by ring opening reaction of L-lactide with diols. Oligolactide acrylates were then synthesized by functionalizing the oligolactide diols with acrylic acid. In this study, three diol ring openers having short and long alkyl chain length were used to investigate the effects of the amount and type of diols on the properties of the oligolactide acrylates. The obtained oligomers were characterized, and the viscosities of oligolactide acrylates were measured. Results showed that oligolactide acrylates were successfully synthesized in all cases of ring openers, as confirmed by 1H-NMR (proton nuclear magnetic resonance spectroscopy and FTIR (Fourier transform infrared spectroscopy. An increase in the alkyl chain length of the ring openers resulted in oligomers with lower viscosity and a decrease in Tg. Following that, the obtained oligolactide acrylates were employed for the formulation of UV-curable screen printing inks and their properties were investigated. Results showed that the inks formulated from oligomers with lower molecular weight exhibited better ink flow. Additionally, all ink films cured by UV radiation were very flexible with excellent adhesion, high impact resistance, and excellent water resistance.

  18. Dielectric and ferroelectric sensing based on molecular recognition in Cu(1,10-phenlothroline)2SeO4.(diol) systems

    Science.gov (United States)

    Ye, Heng-Yun; Liao, Wei-Qiang; Zhou, Qionghua; Zhang, Yi; Wang, Jinlan; You, Yu-Meng; Wang, Jin-Yun; Chen, Zhong-Ning; Li, Peng-Fei; Fu, Da-Wei; Huang, Songping D.; Xiong, Ren-Gen

    2017-02-01

    The process of molecular recognition is the assembly of two or more molecules through weak interactions. Information in the process of molecular recognition can be transmitted to us via physical signals, which may find applications in sensing and switching. The conventional signals are mainly limited to light signal. Here, we describe the recognition of diols with Cu(1,10-phenlothroline)2SeO4 and the transduction of discrete recognition events into dielectric and/or ferroelectric signals. We observe that systems of Cu(1,10-phenlothroline)2SeO4.(diol) exhibit significant dielectric and/or ferroelectric dependence on different diol molecules. The compounds including ethane-1,2-diol or propane-1,2-diol just show small temperature-dependent dielectric anomalies and no reversible polarization, while the compound including ethane-1,3-diol shows giant temperature-dependent dielectric anomalies as well as ferroelectric reversible spontaneous polarization. This finding shows that dielectricity and/or ferroelectricity has the potential to be used for signalling molecular recognition.

  19. Benzo(a)pyrene diol epoxides as intermediates in nucleic acid binding in vitro and in vivo.

    Science.gov (United States)

    Weinstein, I B; Jeffrey, A M; Jennette, K W; Blobstein, S H; Harvey, R G; Harris, C; Autrup, H; Kasai, H; Nakanishi, K

    1976-08-13

    Evidence has been obtained that a specific isomer of a diol epoxide derivative of benzo(a)pyrene, (+/-)-7 beta,8alpha-dihydroxy-9alpha, 10alpha-epoxy-7,8,9,10-tetrahydrobenzo(a)pyrene, is an intermediate in the binding of benzo(a)pyrene to RNA in cultured bovine bronchial mucosa. An adduct is formed between position 10 of this derivative and the 2-amino group of guanine.

  20. Monolayer behaviour of chiral compounds at the air-water interface: 4-hexadecyloxy-butane-1,2-diol

    DEFF Research Database (Denmark)

    Rietz, R.; Rettig, W.; Brezesinski, G.

    1996-01-01

    Monolayers of the pure S-enantiomer (x(S) = 1) and of two mixtures x(S) = 0.75 and x(S) = 0.5 (racemate) of 4-hexadecyloxy-butane-1,2-diol (C16H33-O-CH2-CH2-CHOH-CH2OH) (HOBD) have been studied at the air-water interface by thermodynamic measurements, fluorescence microscopy and X-ray diffraction...

  1. A novel type of banana liquid crystals based on 1-substituted naphtalene-2,7-diol cores

    Czech Academy of Sciences Publication Activity Database

    Svoboda, J.; Novotná, Vladimíra; Kozmík, V.; Glogarová, Milada; Weissflog, W.; Diele, S.; Pelzl, G.

    2003-01-01

    Roč. 13, - (2003), s. 2104-2110 ISSN 0959-9428 R&D Projects: GA ČR(CZ) GA202/02/0840 Grant - others:COST(XE) D14 WG 00015 Institutional research plan: CEZ:AV0Z1010914 Keywords : liquid crystals * banana -shaped mesogens * substituted naphthalene diols Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.659, year: 2003

  2. Identification and characterization of dimeric oxidation products of p-cymene-2,3-diol isolated from Thymus vulgaris L.

    Science.gov (United States)

    Rainis, Guido; Ternes, Waldemar

    2014-01-08

    The aim of this study was to investigate the oxidation products of p-cymene-2,3-diol, a major antioxidative constituent of thyme (Thymus vulgaris L.). Although a dimeric form of p-cymene-2,3-diol and some derivative substances exhibiting valuable food technological and health-promoting properties have been reported in earlier publications, no obvious correlation has been shown between these substances. A modified HPLC-ESI-MS method made it possible to prove that two dimers, 3,4,3',4'-tetrahydroxy-5,5'-diisopropyl-2,2'-dimethylbiphenyl (1) and the newly identified 3',4'-dihydroxy-5,5'-diisopropyl-2,2'-dimethylbiphenyl-3,4-dione (2), are oxidation products of p-cymene-2,3-diol. 2 was characterized by the fragmentation pattern determined by multiple mass spectrometry, (1)H NMR, (13)C NMR, H-H COSY, HSQC, and HMBC. Both biphenyls were also quantitated in freeze-dried thyme as well as in a food matrix spiked with thyme extract. Model experiments using raw and cooked minced pork meat as matrix and sodium nitrite as oxidizing and reduction agent with and without ascorbic acid as protective reagent showed the correlation between food processing and dimer generation.

  3. Aggressive electrolyte poisons and multifunctional fluids comprised of diols and diamines for emergency shutdown of lithium-ion batteries

    Science.gov (United States)

    Noelle, Daniel J.; Shi, Yang; Wang, Meng; Le, Anh V.; Qiao, Yu

    2018-04-01

    Electrolyte poisons comprised of diols and diamines are investigated for the intended function of exacerbating internal resistance in lithium-ion batteries upon short circuit failure, to quickly arrest uncontrolled joule heat generation in the earliest stages. The competing dynamics of powerful short circuit currents and electrolyte poisoning interactions are evaluated via simultaneous nail penetration and poison injection of LIR2450 format LiCoO2/graphite 120 mAh coin cells. To forcibly increase electrolyte impedance, diols serve to hinder charge-carrying ion mobility by raising solution viscosity, while diamines disrupt solvent permittivity by rapidly polymerizing the ethylene carbonate solvent. Diamines demonstrate great potency, and are suitable for integration into battery cells within chemically-inert, breakable containers, rigged for release upon mechanical activation. Mixtures of 1,2-ethanediol and 1,2-ethanediamine show synergistic poisoning effects, decreasing peak temperature accrued by 70% when introduced simultaneously upon nail penetration. With the innate presence and abundance of diols and diamines in electric vehicle heat exchangers, they may be employed for multifunctional applications.

  4. Novel approaches to analysis of 3-chloropropane-1,2-diol esters in vegetable oils.

    Science.gov (United States)

    Moravcova, Eliska; Vaclavik, Lukas; Lacina, Ondrej; Hrbek, Vojtech; Riddellova, Katerina; Hajslova, Jana

    2012-03-01

    A sensitive and accurate method utilizing ultrahigh performance liquid chromatography (U-HPLC) coupled to high resolution mass spectrometry based on orbitrap technology (orbitrapMS) for the analysis of nine 3-chloropropane-1,2-diol (3-MCPD) diesters in vegetable oils was developed. To remove the interfering triacylglycerols that induce strong matrix effects, a clean-up step on silica gel column was used. The quantitative analysis was performed with the use of deuterium-labeled internal standards. The lowest calibration levels estimated for the respective analytes ranged from 2 to 5 μg kg(-1). Good recovery values (89-120%) and repeatability (RSD 5-9%) was obtained at spiking levels of 2 and 10 mg kg(-1). As an alternative, a novel ambient desorption ionization technique, direct analysis in real time (DART), hyphenated with orbitrapMS, was employed for no separation, high-throughput, semi-quantitative screening of 3-MCPD diesters in samples obtained by chromatographic fractionation. Additionally, the levels of 3-MCPD diesters measured in reallife vegetable oil samples (palm oil, sunflower oil, rapeseed oil) using both methods are reported. Relatively good agreement of the data generated by U-HPLC-orbitrapMS and DART-orbitrapMS were observed. With regard to a low ionization yield achieved for 3-MCPD monoesters, the methods presented in this paper were not yet applicable for the analysis of these contaminants at the naturally occurring levels.

  5. Formation of monochloropropane-1,2-diol and its esters in biscuits during baking.

    Science.gov (United States)

    Mogol, Burçe Ataç; Pye, Céline; Anderson, Warwick; Crews, Colin; Gökmen, Vural

    2014-07-23

    The formation of free monochloropropane-1,2-diol (3-MCPD and 2-MCPD) and its esters (bound-MCPD) was investigated in biscuits baked with various time and temperature combinations. The effect of salt as a source of chloride on the formation of these processing contaminants was also determined. Kinetic examination of the data indicated that an increasing baking temperature led to an increase in the reaction rate constants for 3-MCPD, 2-MCPD, and bound-MCPD. The activation energies of formation of 3-MCPD and 2-MCPD were found to be 29 kJ mol(-1). Eliminating salt from the recipe decreased 3-MCPD and 2-MCPD formation rate constants in biscuits by 57.5 and 85.4%, respectively. In addition, there was no formation of bound-MCPD in biscuits during baking without salt. Therefore, lowering the thermal load or limiting the chloride concentration should be considered a means of reducing or eliminating the formation of these contaminants in biscuits. Different refined oils were also used in the recipe to test their effect on the occurrence of free MCPD and its esters in biscuits. Besides the baking process, the results also confirmed the role of refined oil in the final concentration of these contaminants in biscuits.

  6. Binding site for the adenosyl group of coenzyme B12 in diol dehydrase

    International Nuclear Information System (INIS)

    Toraya, T.

    1985-01-01

    The binding of cob(II)alamin (CblII) and 5'-deoxyadenosine to diol dehydrase was studied spectroscopically and with [U- 14 C]5'-deoxyadenosine. CblII was bound to this enzyme forming a tight 1:1 complex which was resistant to oxidation by O 2 even in the presence of CN-. An irreversible 1:1:1 ternary complex was formed between enzyme, CblII, and 5'-deoxyadenosine, when the enzyme was incubated first with the nucleoside and then with CblII. When this order of addition of the constituents was reversed, no 5'-deoxyadenosine was bound to the enzyme-CblII complex. Hydroxocobalamin could also bind to the enzyme together with the nucleoside, while other cob(III)alamins bearing a bulkier Co beta ligand displaced the nucleoside upon binding to the enzyme. The binding of [U- 14 C]5'-deoxyadenosine was strongly inhibited by unlabeled 5'-deoxy-ara-adenosine, 4',5'-anhydroadenosine, adenosine, adenine, and 5',8-cyclic adenosine, in this order, but not by 5'-deoxyuridine. These results constitute direct evidence for the presence of the binding site for the adenosyl group of adenosylcobalamin, which is spatially limited to and highly specific for adenine nucleosides. The binding of 5'-deoxyadenosine to the apoenzyme was reversible

  7. Urinary 5α-androstane-3α,17β-diol radioimmunoassay: a new clinical evaluation

    International Nuclear Information System (INIS)

    Wright, F.; Mowszowicz, I.; Mauvais-Jarvis, P.

    1978-01-01

    A rapid specific and reliable RIA for urinary 5α-androstane-3α, 17β-diol (Adiol) is described using chromatographical purification and a specific antibody. Values are reported under some physiological and pathological conditions in 179 individuals. In 43 normal adult men the mean (+- SD) urinary Adiol excretion was 193 +- 77 μg/24 h, and in 29 normal women it was 44 +- 23 μg/24 h. These values are significantly different (P < 0.01). In 49 hirsute women, urinary Adiol Excretion was elevated (137 +- 51 μg/24 h) and significantly different from this value in normal women (P < 0.01). The urinary Adiol excretion in 10 postmenopausal women was very low (< 5 μg/24 h). In normal adult subjects, the theoretical contribution to urinary Adiol of the major secreted androgens was calculated. Whereas dehydroisoandrosterone and dehydroisoandrosterone sulfate yield the same amount of urinary Adiol in both sexes, testosterone is the main precursor of Adiol in men and androstenedione is the main precursor in normal premenopausal and hirsute women. However, the amount of Adiol recovered in the 24-h urine depends not only on the secretion rate of androstenedione and testosterone but is also related to the testosterone 5α-reductase activity present in androgen target cells, especially in sexual skin

  8. Selective hydrodeoxygenation of cyclic vicinal diols to cyclic alcohols over tungsten oxide-palladium catalysts.

    Science.gov (United States)

    Amada, Yasushi; Ota, Nobuhiko; Tamura, Masazumi; Nakagawa, Yoshinao; Tomishige, Keiichi

    2014-08-01

    Hydrodeoxygenation of cyclic vicinal diols such as 1,4-anhydroerythritol was conducted over catalysts containing both a noble metal and a group 5-7 transition-metal oxide. The combination of Pd and WOx allowed the removal of one of the two OH groups selectively. 3-Hydroxytetrahydrofuran was obtained from 1,4-anhydroerythritol in 72 and 74% yield over WOx -Pd/C and WOx -Pd/ZrO2 , respectively. The WOx -Pd/ZrO2 catalyst was reusable without significant loss of activity if the catalyst was calcined as a method of regeneration. Characterization of WOx -Pd/C with temperature-programmed reduction, X-ray diffraction, and transmission electron microscopy/energy-dispersive X-ray spectroscopy suggested that Pd metal particles approximately 9 nm in size were formed on amorphous tungsten oxide particles. A reaction mechanism was proposed on the basis of kinetics, reaction results with tungsten oxides under an atmosphere of Ar, and density functional theory calculations. A tetravalent tungsten center (W(IV) ) was formed by reduction of WO3 with the Pd catalyst and H2 , and this center served as the reductant for partial hydrodeoxygenation. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Exposure assessment of 3-monochloropropane-1, 2-diol esters from edible oils and fats in China.

    Science.gov (United States)

    Li, Chang; Nie, Shao-Ping; Zhou, Yong-Qiang; Xie, Ming-Yong

    2015-01-01

    3-monochoropropane-1, 2-diol (3-MCPD) esters from edible oils are considered to be a possible risk factor for adverse effects in human. In the present study, the exposure assessment of 3-MCPD esters to Chinese population was performed. A total of 143 edible oil and fat samples collected from Chinese markets were determined for the concentrations of 3-MCPD esters. The concentration data together with the data of fats consumed were analyzed by the point evaluation and probabilistic assessment for the exposure assessment. The point evaluation showed that the mean daily intake (DI) of 3-MCPD esters were lower than the value of provisional maximum tolerable daily intake (PMTDI) of 3-MCPD (2 µg/kg BW/d). The mean DI values in different age groups obtained from probabilistic assessment were similar to the results of the point evaluation. However, in high percentiles (95th, 97.5th, 99th), the DI values in all age groups were undesirably higher than the value of PMTDI. Overall, the children and adolescents exposed more to 3-MCPD esters than the adults. Uncertainty was also analyzed for the exposure assessment. Decreasing the level of 3-MCPD esters in edible oils and consuming less oil were top priority to minimize the risk of 3-MCPD esters. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. HILIC separation and quantitation of water-soluble vitamins using diol column.

    Science.gov (United States)

    Karatapanis, Andreas E; Fiamegos, Yiannis C; Stalikas, Constantine D

    2009-04-01

    Hydrophilic interaction liquid-chromatography (HILIC) in conjunction with diode array detection has been applied for the separation of selected-water-soluble vitamins using an end-capped HILIC-diol column. Vitamins with significant biological importance, such as thiamine (B(1)), riboflavin (B(2)), nicotinic acid (B(3)), nicotinamide (B(3)), pyridoxine (B(6)), folic acid (B(9)), cyanocobalamin (B(12)) and ascorbic acid (vitamin C) were simultaneously separated. Chromatographic conditions including type and percentage of organic modifier in the mobile phase, pH, type and concentration of buffer salt and flow rate were investigated. ACN was shown to offer superior separation for the compounds tested as compared to methanol, isopropanol and THF. Isocratic separation and analysis were achieved for six vitamins (B(1), B(2), nicotinic acid/nicotinamide, B(6) and C) at ACN-H(2)O 90:10, containing ammonium acetate 10 mM, triethylamine 20 mM, pH 5.0, using a flow rate of 0.8 mL/min, while a gradient was necessary to resolve a mixture of all eight water-soluble vitamins. The HILIC method was validated and successfully applied to the analysis of a pharmaceutical formulation and an energy drink negating the need for time consuming clean-up steps.

  11. Toxicological assessment of 3-chloropropane-1,2-diol and glycidol fatty acid esters in food.

    Science.gov (United States)

    Bakhiya, Nadiya; Abraham, Klaus; Gürtler, Rainer; Appel, Klaus Erich; Lampen, Alfonso

    2011-04-01

    Fatty acid esters of 3-chloropropane-1,2-diol (3-MCPD) and glycidol are a newly identified class of food process contaminants. They are widespread in refined vegetable oils and fats and have been detected in vegetable fat-containing products, including infant formulas. There are no toxicological data available yet on the 3-MCPD and glycidol esters, and the primary toxicological concern is based on the potential release of 3-MCPD or glycidol from the parent esters by lipase-catalyzed hydrolysis in the gastrointestinal tract. Although 3-MCPD is assessed as a nongenotoxic carcinogen with a tolerable daily intake (TDI) of 2 μg/kg body weight (bw), glycidol is a known genotoxic carcinogen, which induces tumors in numerous organs of rodents. The initial exposure estimates, conducted by Federal Institute for Risk Assessment (BfR) under the assumption that 100% of the 3-MPCD and glycidol are released from their esters, revealed especially that infants being fed commercial infant formula could ingest harmful amounts of 3-MCPD and glycidol. However, the real oral bioavailability may be lower. As this gives rise for toxicological concern, the currently available toxicological data of 3-MCPD and glycidol and their esters are summarized in this review and discussed with regard to data gaps and further research needs. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. 3-Monochloropropane-1,2-diol fatty acid esters in commercial deep-fat fried foods.

    Science.gov (United States)

    Arisseto, Adriana Pavesi; Marcolino, Priscila Francisca Corrêa; Vicente, Eduardo

    2015-01-01

    Levels of 3-monochloropropane-1,2-diol (3-MCPD) fatty acid esters were evaluated in commercial deep-fat fried foods from the Brazilian market using a GC-MS method preceded by acid-catalysed methanolysis. A limit of detection of 0.04 mg kg(-1), a limit of quantitation of 0.08 mg kg(-1), mean recoveries varying from 82% to 92%, and coefficients of variation ranging from 2.5% to 5.0% for repeatability and from 3.6% to 6.5% for within-laboratory reproducibility were obtained during in-house validation. The levels of the compounds in the evaluated samples, expressed as free 3-MCPD equivalent, ranged from not detected to 0.99 mg kg(-)(1), and the highest concentrations were observed in samples of chopped onion and garlic. A preliminary estimation of 3-MCPD intake using these occurrence data suggested low risks to human health, but a potential concern may arise in particular cases of consumers of fried food.

  13. [Occurrence of 3-monochloropropane-1,2-diol (3-MCPD) in food products].

    Science.gov (United States)

    Gawarska, Halina; Sawilska-Rautenstrauch, Dorota; Starski, Andrzej; Karłowski, Kazimierz

    2009-01-01

    3-Monochloropropane-1,2-diol (3-MCPD) is a contaminant belongs to a group of chemicals called chloropropanols. 3-MCPD can be formed in foods as result of processing or storage condition. At the beginning 3-MCPD was identified as a contaminant of the acid-hydrolysed vegetable protein, which is produced using hydrochloric acid and high temperature. Studies have shown that 3-MCPD is carcinogenic for rats, however genotoxic adverse effect was not observed in vivo. The purpose of this studies was determination of 3-MCPD amounts in retail food products and comparison with the EC legislative limit. 99 samples of foodstuffs was tested: soya sauce, hydrolysed vegetable protein (HVP), sugar, instant soups, stock cubes, bakery products, chips and edible fats. 3-MCPD was detected at levels below 10 microg/kg in 15% of the tested samples, and above 10 microg/kg in 63%. 3-MCPD was not occurred in 22% of the tested samples. The samples were analysed by gas chromatography-mass spectrometry (GC/MS).

  14. Antioxidants Inhibit Formation of 3-Monochloropropane-1,2-diol Esters in Model Reactions.

    Science.gov (United States)

    Li, Chang; Jia, Hanbing; Shen, Mingyue; Wang, Yuting; Nie, Shaoping; Chen, Yi; Zhou, Yongqiang; Wang, Yuanxing; Xie, Mingyong

    2015-11-11

    The capacities of six antioxidants to inhibit the formation of 3-monochloropropane-1,2 diol (3-MCPD) esters were examined in this study. Inhibitory capacities of the antioxidants were investigated both in chemical models containing the precursors (tripalmitoyl glycerol, 1,2-dipalmitoyl-sn-glycerol, monopalmitoyl glycerol, and sodium chloride) of 3-MCPD esters and in oil models (rapeseed oil and sodium chloride). Six antioxidants, butylated hydroxytoluene (BHT), butylated hydroxy anisole (BHA), tert-butyl hydroquinone (TBHQ), propyl gallate (PG), L-ascorbyl palmitate (AP), and α-tocopherol (VE), were found to exhibit inhibiting capacities on 3-MCPD ester formation both in chemical models and in oil models. TBHQ provided the highest inhibitory capacity both in chemical models and in oil models; 44% of 3-MCPD ester formation was inhibited in the presence of TBHQ (66 mg/kg of oil) after heating of rapeseed oil at 230 °C for 30 min, followed by PG and AP. BHT, BHA, and VE appeared to have weaker inhibitory abilities in both models. VE exhibited the lowest inhibition rate; 22% of 3-MCPD esters were inhibited in the presence of VE (172 mg/kg of oil) after heating of rapeseed oil at 230 °C for 30 min. In addition, the inhibition rates of PG and VE decreased dramatically with an increase in temperature or heating time. The results suggested that some antioxidants, such as TBHQ, PG, and AP, could be the potential inhibitors of 3-MCPD esters in practice.

  15. Influence of dough ingredients on 3-chloropropane-1,2-diol (3-MCPD) formation in toast.

    Science.gov (United States)

    Breitling-Utzmann, C M; Hrenn, H; Haase, N U; Unbehend, G M

    2005-02-01

    The influence of different dough ingredients such as fat, salt, sourdough, emulsifiers, and sugar on the formation of 3-chloropropane-1,2-diol (3-MCPD) during toast preparation under domestic conditions was investigated. In comparison with a fat-free recipe, addition of 1% peanut fat considerably increased 3-MCPD formation, but varying the fat (2-5%) or salt (1.6-2.4%) contents within technological acceptable limits did not show any significant differences. A baking agent, which is usually commercially applied by many toast bakers or industrial toast manufacturers, increased 3-MCPD formation in toasted bread slices. Considerable evidence was found that the baking agent's main component sucrose had the major part in increasing 3-MCPD levels. Emulsifiers containing monoacylglycerols moderately increased 3-MCPD levels, but the addition of lecithin did not have any significant influence. 3-MCPD levels showed a good correlation with the lightness (L* value) of the bread slices; their 3-MCPD content increased exponentially towards dark coloured toasts. The relation between 3-MCPD and 2-MCPD was an average of 3:1 in all samples. Dichloropropanols such as, for example, 1,3-dichloropropanol could not be detected.

  16. Abscisic (ABA)-aldehyde is a precursor to, and 1',4'-trans-ABA-diol a catabolite of, ABA in apple

    International Nuclear Information System (INIS)

    Rock, C.D.; Zeevaart, J.A.D.

    1990-01-01

    Previous 18 O labeling studies of abscisic acid (ABA) have shown that apple (Malus domestica Borkh. cv Granny Smith) fruits synthesize a majority of [ 18 O]ABA with the label incorporated in the 1'-hydroxyl position and unlabeled in the carboxyl group (JAD Zeevaart, TG Heath, DA Gage [1989] Plant Physiol 91: 1594-1601). It was proposed that exchange of 18 O in the side chain with the medium occurred at an aldehyde intermediate stage of ABA biosynthesis. We have isolated ABA-aldehyde and 1'-4'-trans-ABA-diol (ABA-trans-diol) from 18 O-labeled apple fruit tissue and measured the extent and position of 18 O incorporation by tandem mass spectrometry. 18 O-Labeling patterns of ABA-aldehyde, ABA-trans-diol, and ABA indicate that ABA-aldehyde is a precursor to, and ABA-trans-diol a catabolite of, ABA. Exchange of 18 O in the carbonyl of ABA-aldehyde can be the cause of loss of 18 O from the side chain of [ 18 O]ABA. Results of feeding experiments with deuterated substrates provide further support for the precursor-product relationship of ABA-aldehyde → ABA → ABA-trans-diol. The ABA-aldehyde and ABA-trans-diol contents of fruits and leaves were low, approximately 1 and 0.02 nanograms per gram fresh weight for ABA-aldehyde and ABA-trans-diol, respectively, while ABA levels in fruits ranged from 10 to 200 nanograms per gram fresh weight. ABA biosynthesis was about 10-fold lower in fruits than in leaves. In fruits, the majority of ABA was conjugated to β-D-glucopyranosyl abscisate, whereas in leaves ABA was mainly hydroxylated to phaseic acid. Parallel pathways for ABA and trans-ABA biosynthesis and conjugation in fruits and leaves are proposed

  17. Fingerprinting of traditional Chinese medicines on the C18-Diol mixed-mode column in online or offline two-dimensional liquid chromatography on the single column modes.

    Science.gov (United States)

    Wang, Qing; Tong, Ling; Yao, Lin; Zhang, Peng; Xu, Li

    2016-06-05

    In the present study, a mixed-mode stationary phase, C18-Diol, was applied for fingerprint analysis of traditional Chinese medicines. Hydrophobic, hydrogen bonding and electrostatic interactions were demonstrated to contribute the retention separately or jointly, which endowed the C18-Diol stationary phase with distinct selectivity compared to the bare C18 one. The separation of total alkaloids extracted from Fritillaria hupehensis was compared on the C18-Diol and conventional C18 column with the greater resolving power and better symmetry responses on the former one. Besides, a novel two-dimensional liquid chromatography on the single column (2D-LC-1C) was realized on C18-Diol with the offline mode for the alcohol extract of Fritillaria hupehensis and online mode for Ligusticum chuanxiong Hort. The early co-eluted extracted components with great polarity on the first dimension were reinjected on the same column and well separated on the second dimension. The results exhibited that the two complementary RPLC and HILIC modes on C18-Diol stationary phase enhanced the separation capacity and revealed more abundant chemical information of the sample, which was a powerful tool in analyzing complex herbal medicines. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Iridium- and ruthenium-catalysed synthesis of 2,3-disubstituted indoles from anilines and vicinal diols

    DEFF Research Database (Denmark)

    Tursky, Matyas; Lorentz-Petersen, Linda Luise Reeh; Olsen, L. B.

    2010-01-01

    A straightforward and atom-economical method is described for the synthesis of 2,3-disubstituted indoles. Anilines and 1,2-diols are condensed under neat conditions with catalytic amounts of either [Cp*IrCl2](2)/MsOH or RuCl3 center dot xH(2)O/phosphine (phosphine = PPh3 or xantphos). The reactio...... the alpha-hydroxyimine which rearranges to the corresponding alpha-aminoketone. Acid-or metal-catalysed electrophilic ring-closure with the release of water then furnishes the indole product....

  19. Influence of oil composition on the formation of fatty acid esters of 2-chloropropane-1,3-diol (2-MCPD) and 3-chloropropane-1,2-diol (3-MCPD) under conditions simulating oil refining.

    Science.gov (United States)

    Ermacora, Alessia; Hrncirik, Karel

    2014-10-15

    The toxicological relevance and widespread occurrence of fatty acid esters of 2-chloropropane-1,3-diol (2-MCPD) and 3-chloropropane-1,2-diol (3-MCPD) in refined oils and fats have recently triggered an interest in the mechanism of formation and decomposition of these contaminants during oil processing. In this work, the effect of the main precursors, namely acylglycerols and chlorinated compounds, on the formation yield of MCPD esters was investigated in model systems simulating oil deodorization. The composition of the oils was modified by enzymatic hydrolysis, silica gel purification and application of various refining steps prior to deodorization (namely degumming, neutralization, bleaching). Partial acylglycerols showed greater ability, than did triacylglycerols, to form MCPD esters. However, no direct correlation was found between these two parameters, since the availability of chloride ions was the main limiting factor in the formation reaction. Polar chlorinated compounds were found to be the main chloride donors, although the presence of reactive non-polar chloride-donating species was also observed. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Synthesis and characterization of biodegradable poly (ethylene glycol) and poly (caprolactone diol) end capped poly (propylene fumarate) cross linked amphiphilic hydrogel as tissue engineering scaffold material.

    Science.gov (United States)

    Krishna, Lekshmi; Jayabalan, Muthu

    2009-12-01

    Biodegradable poly (caprolactone diol-co-propylene fumarate-co-ethylene glycol) amphiphilic polymer with poly (ethylene glycol) and poly (caprolactone diol) chain ends (PCL-PPF-PEG) was prepared. PCL-PPF-PEG undergoes fast setting with acrylamide (aqueous solution) by free radical polymerization and produces a crosslinked hydrogel. The cross linked and freeze-dried amphiphilic material has porous and interconnected network. It undergoes higher degree of swelling and water absorption to form hydrogel with hydrophilic and hydrophobic domains at the surface and appreciable tensile strength. The present hydrogel is compatible with L929 fibroblast cells. PCL-PPF-PEG/acrylamide hydrogel is a candidate scaffold material for tissue engineering applications.

  1. Metabolism of isoeugenol via isoeugenol-diol by a newly isolated strain of Bacillus subtilis HS8.

    Science.gov (United States)

    Zhang, Yongmei; Xu, Ping; Han, Shuai; Yan, Haiqin; Ma, Cuiqing

    2006-12-01

    A bacterium designated as HS8 was newly isolated from soil based on its ability to degrade isoeugenol. The strain was identified as Bacillus subtilis according to its 16S rDNA sequence analysis and biochemical characteristics. The metabolic pathway for the degradation of isoeugenol was examined. Isoeugenol-diol, for the first time, was detected as an intermediate from isoeugenol to vanillin by a bacterial strain. Isoeugenol was converted to vanillin via isoeugenol-diol, and vanillin was then metabolized via vanillic acid to guaiacol by strain HS8. These metabolites, vanillin, vanillic acid, and guaiacol, are all valuable aromatic compounds in flavor production. At the same time, the bipolymerization of isoeugenol was observed, which produced dehydrodiisoeugenol and decreased the vanillin yield. High level of vanillic acid decarboxylase activity was detected in cell-free extract. These findings provided a detailed profile of isoeugenol metabolism by a B. subtilis strain for the first time, which would improve the production of valuable aromatic compounds by biotechnology.

  2. Cross-Linked Dependency of Boronic Acid-Conjugated Chitosan Nanoparticles by Diols for Sustained Insulin Release

    Directory of Open Access Journals (Sweden)

    Nabil A. Siddiqui

    2016-10-01

    Full Text Available Boronic acids have been widely investigated for their potential use as glucose sensors in glucose responsive polymeric insulin delivery systems. Interactions between cyclic diols and boronic acids, anchored to polymeric delivery systems, may result in swelling of the delivery system, releasing the drug. In this study, 4-formylphenylboronic acid conjugated chitosan was formulated into insulin containing nanoparticles via polyelectrolyte complexation. The nanoparticles had an average diameter of 140 ± 12.8 nm, polydispersity index of 0.17 ± 0.1, zeta potential of +19.1 ± 0.69 mV, encapsulation efficiency of 81% ± 1.2%, and an insulin loading capacity of 46% ± 1.8% w/w. Changes in size of the nanoparticles and release of insulin were type of sugar- and concentration-dependent. High concentration of diols resulted in a sustained release of insulin due to crosslink formation with boronic acid moieties within the nanoparticles. The formulation has potential to be developed into a self-regulated insulin delivery system for the treatment of diabetes.

  3. Preparation and surface active properties of oxypropylated diol monoesters of fatty acids with an amide oxime terminal group

    Directory of Open Access Journals (Sweden)

    Eissa, A. M.F.

    1994-10-01

    Full Text Available Locally produced non-edible oil, namely, rice bran oil (R.B.O. was utilized as starting materials for preparing new nonionic surfactant. Oxypropylated diol monoesters of linoleic and rice bran oil fatty acids were prepared. Also amide oxime derivatives were obtained. Surface active properties of these compounds were measured. Under neutral condition amide eximes served as nonionic surfactants and their properties were similar to other oxypropylated monoesters.

    Se ha utilizado un aceite no comestible de producción local, denominado, aceite de salvado de arroz (R.B.O. como materia prima para la preparación de nuevos tensioactivos no iónicos. Se prepararon diol monoésteres oxipropilados de ácido linoleico y ácidos grasos de aceite de salvado de arroz. También se obtuvieron los derivados de amido oxima. Se midieron las propiedades de tensión superficial de estos compuestos. Bajo condiciones neutras las amido eximas sirvieron como tensioactivos no iónicos y sus propiedades fueron similares a los de otros monoésteres oxipropilados.

  4. Studies on Poly(propylene fumarate-co-caprolactone diol Thermoset Composites towards the Development of Biodegradable Bone Fixation Devices

    Directory of Open Access Journals (Sweden)

    M. Jayabalan

    2009-01-01

    Full Text Available The effect of reinforcement in the cross-linked poly(propylene fumarate-co-caprolactone diol thermoset composites based on Kevlar fibres and hydroxyapatite was studied. Cross-linked poly(propylene fumarate-co-caprolactone diol was also studied without any reinforcement for comparison. The reinforcing fibre acts as a barrier for the curing reaction leading to longer setting time and lesser cross-link density. The fibre and HA reinforced composites have almost the same compressive strength. Nonreinforced material undergoes greater degree of swelling. Among the reinforced materials, the hydroxyapatite reinforced composite has a much higher swelling percentage than the fibre reinforced one. The studies on in vitro degradation of the cured materials reveal hydrolytic degradation in Ringer's solution and PBS medium during aging. All the three materials are found to swell initially in Ringer's solution and PBS medium during aging and then undergo gradual degradation. Compression properties of these cross-linked composites increase with aging; HA reinforced composite has the highest compressive strength and compressive modulus, whereas the aged fibre-reinforced composite has the least compressive strength and modulus.

  5. Studies on Poly(propylene fumarate-co-caprolactone diol) Thermoset Composites towards the Development of Biodegradable Bone Fixation Devices.

    Science.gov (United States)

    Jayabalan, M

    2009-01-01

    The effect of reinforcement in the cross-linked poly(propylene fumarate-co-caprolactone diol) thermoset composites based on Kevlar fibres and hydroxyapatite was studied. Cross-linked poly(propylene fumarate-co-caprolactone diol) was also studied without any reinforcement for comparison. The reinforcing fibre acts as a barrier for the curing reaction leading to longer setting time and lesser cross-link density. The fibre and HA reinforced composites have almost the same compressive strength. Nonreinforced material undergoes greater degree of swelling. Among the reinforced materials, the hydroxyapatite reinforced composite has a much higher swelling percentage than the fibre reinforced one. The studies on in vitro degradation of the cured materials reveal hydrolytic degradation in Ringer's solution and PBS medium during aging. All the three materials are found to swell initially in Ringer's solution and PBS medium during aging and then undergo gradual degradation. Compression properties of these cross-linked composites increase with aging; HA reinforced composite has the highest compressive strength and compressive modulus, whereas the aged fibre-reinforced composite has the least compressive strength and modulus.

  6. Letter to the Editor: About "Studies of Viscosity and Excess Molar Volume of Binary Mixtures of Propane-1,2 diol with Water at Various Temperatures"

    Czech Academy of Sciences Publication Activity Database

    Linek, Jan

    2003-01-01

    Roč. 208, 1-2 (2003), s. 261-263 ISSN 0378-3812 R&D Projects: GA ČR GA203/02/1098 Institutional research plan: CEZ:AV0Z4072921 Keywords : water * propane-1,2-diol * physical properties Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.165, year: 2003

  7. (E-2-((4R,5R-5-((Benzyloxymethyl-2,2-dimethyl-1,3-dioxolan-4-ylbut-2-ene-1,4-diol

    Directory of Open Access Journals (Sweden)

    Carlos R. Carreras

    2010-04-01

    Full Text Available The synthesis of (E-2-((4R,5R-5-((benzyloxymethyl-2,2-dimethyl-1,3-dioxolan-4-ylbut-2-ene-1,4-diol by a one-step reduction of the appropriate 2-substituted butenolide is reported. Product characterization was carried out by IR, 1H NMR, 13C NMR, MS, elemental analysis and optical rotation.

  8. Synthesis and thermal behavior of telechelic poly(butadiene)diols with azobenzene-based liquid-crystalline units in side chains

    Czech Academy of Sciences Publication Activity Database

    Poláková, Lenka; Sedláková, Zdeňka; Látalová, Petra

    2010-01-01

    Roč. 64, č. 4 (2010), s. 315-326 ISSN 0170-0839 R&D Projects: GA ČR GA202/09/2078 Institutional research plan: CEZ:AV0Z40500505 Keywords : azobenzene mesogens * radical addition * poly(butadiene)diols Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.215, year: 2010

  9. Human hair follicle benzo(a)pyrene and benzo(a)pyrene 7, 8-diol metabolism: effect of exposure to a coal tar-containing shampoo

    Energy Technology Data Exchange (ETDEWEB)

    Merk, H.F.; Mukhtar, H.; Kaufmann, I.; Das, M.; Bickers, D.R.

    1987-01-01

    Hair follicles are a readily available source of human epithelial tissue and offer an excellent system with which to study carcinogen metabolism in human populations. In this study hair follicles were employed to measure the metabolism of benzo(a)pyrene (BP), benzo(a)pyrene - 7,8-diol (BP 7,8-diol) and the enzyme mediated binding of /sup 3/H-BP to DNA. The effect of human exposure to a crude coal tar (CCT) - containing shampoo, a preparation rich in polycyclic aromatic hydrocarbons (PAHs on these parameters was also evaluated. It was found that aryl hydrocarbon hydroxylase (AHH) activity increased after use of the shampoo and enhancement of enzyme-mediated binding of BP to DNA was detected in most subjects. Hair follicles were shown to convert BP to several metabolic species and BP, 7,8-diol was also metabolised. Clotrimazole, a known inhibitor of the metabolism of BP was found to inhibit AHH and the metabolism of BP and BP 7,8-diol in human hair follicles, as were other imidazole compounds. The studies show that hair follicles represent an accessible tissue suitable for assessing the extent of PAH carcinogen metabolism in human subjects. Furthermore enzyme activity critical to cancer induction by PAHs was shown to be inducible following the use of a CCT-containing shampoo. Imidazole compounds were shown to be possible effective anti-carcinogens in human populations. 29 refs.

  10. High-Throughput Assay for Enantiomeric Excess Determination in 1,2- and 1,3-Diols and Direct Asymmetric Reaction Screening.

    Science.gov (United States)

    Shcherbakova, Elena G; Brega, Valentina; Lynch, Vincent M; James, Tony D; Anzenbacher, Pavel

    2017-07-26

    A simple and efficient method for determination of the yield, enantiomeric/diasteriomeric excess (ee/de), and absolute configuration of crude chiral diols without the need of work-up and product isolation in a high throughput setting is described. This approach utilizes a self-assembled iminoboronate ester formed as a product by dynamic covalent self-assembly of a chiral diol with an enantiopure fluorescent amine such as tryptophan methyl ester or tryptophanol and 2-formylphenylboronic acid. The resulting diastereomeric boronates display different photophysical properties and allow for fluorescence-based ee determination of molecules containing a 1,2- or 1,3-diol moiety. This method has been utilized for the screening of ee in a number of chiral diols including atorvastatin, a statin used for the treatment of hypercholesterolemia. Noyori asymmetric hydrogenation of benzil was performed in a highly parallel fashion with errors products from the parallel asymmetric synthesis in real time and in a high-throughput screening (HTS) fashion. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Chiral separation of synthetic vicinal diol compounds by capillary zone electrophoresis with borate buffer and beta-cyclodextrin as buffer additive.

    Science.gov (United States)

    Zhao, Yan; Yang, Xingbin; Jiang, Ru; Sun, Xiaoli; Liu, Wenmin; Zhang, Shengyong

    2006-05-01

    The investigation on capillary electrophoretic enantioseparation of six synthetic compounds containing vicinal diol groups has been undertaken to acquire the optimum conditions using native beta-cyclodextrin (beta-CD) as chiral selector and borate as a background electrolyte. The separation was carried out in an uncoated capillary (58.5 cm x 75 microm i.d., effective length 48.5 cm) and the effects of several important factors were investigated in detail. The results showed that beta-CD as a chiral selector exhibited good enantioselectivity and that the enantioseparation was greatly influenced by the structure of the diols, the borate concentration and the buffer pH. The optimum performance was obtained for the chiral vicinal diols under the conditions of 200 mM borate buffer of pH 9.8 containing 1.7% beta-CD at an applied voltage of 15 kV and a capillary temperature of 20 degrees C. Under the conditions, four diols were baseline separated with fast analysis time and the good theoretical plate numbers (above 10 x 10(4)) and favorable migration-time reproducibilities (RSDs below 3.0%) were obtained. The separation results were satisfactory.

  12. Glass transition and the rigid amorphous phase in semicrystalline blends of bacterial polyhydroxybutyrate PHB with low molecular mass atactic R,S-PHB-diol

    NARCIS (Netherlands)

    Hoehne, G.W.H.

    2004-01-01

    The glass transition and the crystallinity of blends of isotactic bacterial PHB and low molecular mass atactic R, S-PHB-diols was investigated by means of differential scanning calorimetry (DSC), temperature-modulated DSC and dielectric spectroscopy. It was found that (i) Tg of crystallized blends

  13. Speed of sound in saturated aliphatic alcohols (propan-2-ol, butan-2-ol, and 2-methylpropan-1-ol) and alkanediols (ethane-1,2-diol, propane-1,2- and -1,3-diol) at temperature between 253.15 K and 353.15 K and pressures up to 30 MPa

    International Nuclear Information System (INIS)

    Dávila, María J.; Gedanitz, Holger; Span, Roland

    2016-01-01

    Highlights: • Speed of sound measurements were made in aliphatic alcohols and alkanediols. • Speeds of sound were measured in a wide temperature and pressure range. • A pulse-echo method with a double path type sensor operating at 8 MHz was employed. • A double polynomial equation was used to fit the experimental speed of sound data. • The accurate results were compared with available literature sources. - Abstract: Speeds of sound have been measured in three saturated aliphatic alcohols (propan-2-ol, butan-2-ol, and 2-methylpropan-1-ol) and three alkanediols (ethane-1,2-diol, propane-1,2- and -1,3-diol) in the temperature range from (253.15 to 353.15) K and pressures up to 30 MPa by use of a pulse-echo method with a double path type sensor operating at 8 MHz. The expanded overall uncertainties (k = 2) in the speed of sound measurements are estimated to be 0.013% for propan-2-ol, 0.019% for butan-2-ol, 0.01% for 2-methylpropan-1-ol, 0.009% for ethane-1,2-diol, 0.02% for propane-1,2-diol, and 0.07% for propane-1,3-diol. Experimental speeds of sound data were correlated with the temperature and pressure with an empirical double polynomial equation. Our results were also compared with the available literature data and a satisfactory agreement was found.

  14. Highly Sensitive Determination of 2,4,6-Trinitrotoluene and Related Byproducts Using a Diol Functionalized Column for High Performance Liquid Chromatography

    Science.gov (United States)

    Gumuscu, Burcu; Erdogan, Zeynep; Guler, Mustafa O.; Tekinay, Turgay

    2014-01-01

    In this work, a new detection method for complete separation of 2,4,6-trinitrotoluene (TNT); 2,4-dinitrotoluene (2,4-DNT); 2,6-dinitrotoluene (2,6-DNT); 2-aminodinitrotoluene (2-ADNT) and 4-aminodinitrotoluene (4-ADNT) molecules in high-performance liquid-chromatography (HPLC) with UV sensor has been developed using diol column. This approach improves on cost, time, and sensitivity over the existing methods, providing a simple and effective alternative. Total analysis time was less than 13 minutes including column re-equilibration between runs, in which water and acetonitrile were used as gradient elution solvents. Under optimized conditions, the minimum resolution between 2,4-DNT and 2,6-DNT peaks was 2.06. The recovery rates for spiked environmental samples were between 95–98%. The detection limits for diol column ranged from 0.78 to 1.17 µg/L for TNT and its byproducts. While the solvent consumption was 26.4 mL/min for two-phase EPA and 30 mL/min for EPA 8330 methods, it was only 8.8 mL/min for diol column. The resolution was improved up to 49% respect to two-phase EPA and EPA 8330 methods. When compared to C-18 and phenyl-3 columns, solvent usage was reduced up to 64% using diol column and resolution was enhanced approximately two-fold. The sensitivity of diol column was afforded by the hydroxyl groups on polyol layer, joining the formation of charge-transfer complexes with nitroaromatic compounds according to acceptor-donor interactions. Having compliance with current requirements, the proposed method demonstrates sensitive and robust separation. PMID:24905826

  15. Highly sensitive determination of 2,4,6-trinitrotoluene and related byproducts using a diol functionalized column for high performance liquid chromatography.

    Science.gov (United States)

    Gumuscu, Burcu; Erdogan, Zeynep; Guler, Mustafa O; Tekinay, Turgay

    2014-01-01

    In this work, a new detection method for complete separation of 2,4,6-trinitrotoluene (TNT); 2,4-dinitrotoluene (2,4-DNT); 2,6-dinitrotoluene (2,6-DNT); 2-aminodinitrotoluene (2-ADNT) and 4-aminodinitrotoluene (4-ADNT) molecules in high-performance liquid-chromatography (HPLC) with UV sensor has been developed using diol column. This approach improves on cost, time, and sensitivity over the existing methods, providing a simple and effective alternative. Total analysis time was less than 13 minutes including column re-equilibration between runs, in which water and acetonitrile were used as gradient elution solvents. Under optimized conditions, the minimum resolution between 2,4-DNT and 2,6-DNT peaks was 2.06. The recovery rates for spiked environmental samples were between 95-98%. The detection limits for diol column ranged from 0.78 to 1.17 µg/L for TNT and its byproducts. While the solvent consumption was 26.4 mL/min for two-phase EPA and 30 mL/min for EPA 8330 methods, it was only 8.8 mL/min for diol column. The resolution was improved up to 49% respect to two-phase EPA and EPA 8330 methods. When compared to C-18 and phenyl-3 columns, solvent usage was reduced up to 64% using diol column and resolution was enhanced approximately two-fold. The sensitivity of diol column was afforded by the hydroxyl groups on polyol layer, joining the formation of charge-transfer complexes with nitroaromatic compounds according to acceptor-donor interactions. Having compliance with current requirements, the proposed method demonstrates sensitive and robust separation.

  16. Highly sensitive determination of 2,4,6-trinitrotoluene and related byproducts using a diol functionalized column for high performance liquid chromatography.

    Directory of Open Access Journals (Sweden)

    Burcu Gumuscu

    Full Text Available In this work, a new detection method for complete separation of 2,4,6-trinitrotoluene (TNT; 2,4-dinitrotoluene (2,4-DNT; 2,6-dinitrotoluene (2,6-DNT; 2-aminodinitrotoluene (2-ADNT and 4-aminodinitrotoluene (4-ADNT molecules in high-performance liquid-chromatography (HPLC with UV sensor has been developed using diol column. This approach improves on cost, time, and sensitivity over the existing methods, providing a simple and effective alternative. Total analysis time was less than 13 minutes including column re-equilibration between runs, in which water and acetonitrile were used as gradient elution solvents. Under optimized conditions, the minimum resolution between 2,4-DNT and 2,6-DNT peaks was 2.06. The recovery rates for spiked environmental samples were between 95-98%. The detection limits for diol column ranged from 0.78 to 1.17 µg/L for TNT and its byproducts. While the solvent consumption was 26.4 mL/min for two-phase EPA and 30 mL/min for EPA 8330 methods, it was only 8.8 mL/min for diol column. The resolution was improved up to 49% respect to two-phase EPA and EPA 8330 methods. When compared to C-18 and phenyl-3 columns, solvent usage was reduced up to 64% using diol column and resolution was enhanced approximately two-fold. The sensitivity of diol column was afforded by the hydroxyl groups on polyol layer, joining the formation of charge-transfer complexes with nitroaromatic compounds according to acceptor-donor interactions. Having compliance with current requirements, the proposed method demonstrates sensitive and robust separation.

  17. Synthesis, Characterizations and Investigation of Electrochemical Behaviours of 4-[(2-Hydroxyphenyliminomethyl]benzene-1,3-diol

    Directory of Open Access Journals (Sweden)

    Aysen D. Mulazimoglu

    2009-01-01

    Full Text Available This Schiff base ligand, 4-[(2-hydroxyphenylimino methyl]benzene-1,3-diol (HIBD was synthesized by reaction of 2-aminophenol and 2,4-dihydroxybenzaldehyde. The ligand was characterized by elemental analysis, FT-IR and 1H-NMR. Electrochemical behaviors were investigated on the glassy carbon electrode (GC surface with cyclic voltammetry (CV. The modification of HIBD on the GC was performed in +0.3 V and +2,8 V potential range using 100 mV s-1 scanning rate having 5 cycle. For the characterization of the modified surfaces 1 mM ferrocene redox probe in 0,1 M tetrabutylammonium tetrafluoroborate (TBATFB and 1 mM ferricyanide redox probe in 0.1 M H2SO4 were used.

  18. Formation and reduction of 3-monochloropropane-1,2-diol esters in peanut oil during physical refining.

    Science.gov (United States)

    Li, Chang; Li, Linyan; Jia, Hanbing; Wang, Yuting; Shen, Mingyue; Nie, Shaoping; Xie, Mingyong

    2016-05-15

    In the present study, lab-scale physical refining processes were investigated for their effects on the formation of 3-monochloropropane-1,2-diol (3-MCPD) esters. The potential precursors, partial acylglycerols and chlorines were determined before each refining step. 3-MCPD esters were not detected in degummed and bleached oil when the crude oils were extracted by solvent. While in the hot squeezed crude oils, 3-MCPD esters were detected with low amounts. 3-MCPD esters were generated with maximum values in 1-1.5h at a certain deodorizing temperature (220-260°C). Chlorine seemed to be more effective precursor than partial acylglycerol. By washing bleached oil before deodorization with ethanol solution, the precursors were removed partially and the content of 3-MCPD esters decreased to some extent accordingly. Diacetin was found to reduce 3-MCPD esters effectively. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Occurrence of 3-chloro-propane-1,2-diol (3-MCPD) and related compounds in foods: a review.

    Science.gov (United States)

    Hamlet, C G; Sadd, P A; Crews, C; Velísek, J; Baxter, D E

    2002-07-01

    A critical review of the occurrence of 3-chloro-propane-1,2-diol (3-MCPD) in foods not known to contain hydrolysed vegetable proteins is presented. The review covers the properties and chemistry of 3-MCPD and the current methods of analysis in foodstuffs. The results of UK surveys of 3-MCPD occurrence in both retail foods and commercial food ingredients are discussed with particular reference to cereal, meat and dairy products. The possible mechanisms for the formation and decay of 3-MCPD in foods are suggested. The review does not cover the detailed toxicology of 3-MCPD and its occurrence in hydrolysed vegetable proteins, which have been considered elsewhere, nor possible issues such as in-vivo formation.

  20. Exploring Lactobacillus reuteri DSM20016 as a biocatalyst for transformation of longer chain 1,2-diols: Limits with microcompartment.

    Science.gov (United States)

    Chen, Lu; Hatti-Kaul, Rajni

    2017-01-01

    Lactobacillus reuteri metabolises glycerol efficiently to form 3-hydroxypropionic acid (3-HP) and 1,3-propanediol (1,3PDO) by the same mechanism as that for 1,2-propanediol (1,2PDO) conversion to propionic acid and propanol via its propanediol utilization (pdu) pathway. Pdu enzymes are encoded by the pdu-operon, which also contain genes encoding the shell proteins of the microcompartment housing the metabolic pathway. In this work the selectivity and kinetics of the reactions catalysed by L. reuteri DSM20016 Pdu enzymes glycerol dehydratase (GDH), 1,3-propanediol oxidoreductase (PduQ) and coenzyme-A acylating propionaldehyde dehydrogenase (PduP), produced recombinantly, was investigated against corresponding substrates of different chain lengths. Glycerol dehydratase exhibited activity against C2-C4 polyols, with the highest activity against glycerol and 1,2-propanediol (1,2-PDO). A double mutant of the pduC gene of GDH (PduC-S302A/Q337A) was constructed that displayed lowered activity against glycerol and 1,2PDO but extended the substrate range upto C6-diol. The best substrate for both PduQ and PduP was 3-hydroxypropanal (3HPA), although PduP exhibited nearly 10-fold higher specific activity. The enzymes also showed some activity against C3-C10 aliphatic aldehydes, with PduP having higher relative activity. Subsequently, transformation of polyols using whole cells of L. reuteri containing the wild type- and mutated GDH, respectively, confirmed the reduced activity of the mutant against glycerol and 1,2PDO, but its activity against longer substrates was negligible. In contrast, recombinant Escherichia coli BL21(DE3) cells harboring the GDH variant converted diols with up to C6 carbon chain length to their respective aldehydes, suggesting that the protein shell of the microcompartment in L. reuteri posed a barrier to the passage of longer chain substrate.

  1. Metabolites of the PAH diol epoxide pathway and other urinary biomarkers of phenanthrene and pyrene in workers with and without exposure to bitumen fumes.

    Science.gov (United States)

    Lotz, Anne; Pesch, Beate; Dettbarn, Gerhard; Raulf, Monika; Welge, Peter; Rihs, Hans-Peter; Breuer, Dietmar; Gabriel, Stefan; Hahn, Jens-Uwe; Brüning, Thomas; Seidel, Albrecht

    2016-11-01

    This study investigates the diol epoxide pathway of phenanthrene (PHE) together with phenolic metabolites of PHE and pyrene (PYR) in workers with and without exposure to bitumen fumes. The metabolite concentrations were determined in urine samples collected from 91 mastic asphalt workers and 42 construction workers as reference group before and after shift. During shift, vapours and aerosols of bitumen were measured according to a German protocol in the workers' breathing zone. The median concentration of vapours and aerosols of bitumen in mastic asphalt workers was 6.3 mg/m 3 . Metabolite concentrations were highest in post-shift urines of smokers with bitumen exposure and showed an increase during shift. The Spearman correlations between the creatinine-adjusted concentrations of metabolites and vapours and aerosols of bitumen in non-smokers were weak (e.g. sum of Di-OH-PYR: 0.28) or negligible (e.g. 1,2-PHE-diol: 0.08; PHE-tetrol: 0.12). Metabolites from the diol epoxide pathway of PHE were excreted in higher concentrations than phenolic metabolites (post-shift, non-smoking asphalt workers: 1,2-PHE-diol 2.59 µg/g crea vs. sum of all OH-PHE 1.87 µg/g crea). 1,2-PHE-diol was weakly correlated with PHE-tetrol (Spearman coefficient 0.30), an endpoint of the diol epoxide pathway. By contrast, we found a close correlation between the sum of 1,6-DiOH-PYR and 1,8-DiOH-PYR with 1-OH-PYR (Spearman coefficient 0.76). Most urinary PAH metabolites were higher after shift in bitumen-exposed workers, although the association with bitumen was weak or negligible likely due to the small PAH content. The additional metabolites of PHE and PYR complete the picture of the complex metabolic pathways. Nevertheless, none of the PAH metabolites can be considered to be a specific biomarker for bitumen exposure.

  2. 2-Butyne-1,4-diol as a novel corrosion inhibitor for API X65 steel pipeline in carbonate/bicarbonate solution

    Energy Technology Data Exchange (ETDEWEB)

    Sadeghi Meresht, E. [Materials Engineering Department, Faculty of Engineering, Tarbiat Modares University, 1411713114, Tehran (Iran, Islamic Republic of); Shahrabi Farahani, T., E-mail: tshahrabi34@modares.ac.ir [Materials Engineering Department, Faculty of Engineering, Tarbiat Modares University, 1411713114, Tehran (Iran, Islamic Republic of); Neshati, J. [Research Institute of Petroleum Industry, RIPI, 1485733111, Tehran (Iran, Islamic Republic of)

    2012-01-15

    Highlights: Black-Right-Pointing-Pointer Corrosion of API 5L X65 is effectively reduced by the addition of the inhibitor. Black-Right-Pointing-Pointer The techniques include weight loss, potentiodynamic polarization, EIS and AFM. Black-Right-Pointing-Pointer 2-Butyne-1,4-diol acts as a mixed-type inhibitor. Black-Right-Pointing-Pointer The adsorption of 2-butyne-1,4-diol obeys Langmuir adsorption isotherm. - Abstract: The inhibition effects of 2-butyne-1,4-diol on the corrosion susceptibility of grade API 5L X65 steel pipeline in 2 M Na{sub 2}CO{sub 3}/1 M NaHCO{sub 3} solution were studied by electrochemical techniques and weight loss measurements. The results indicated that this inhibitor was a mixed-type inhibitor, with a maximum percentage inhibition efficiency of approximately 92% in the presence of 5 mM inhibitor. Atomic force microscopy revealed that a protective film was formed on the surface of the inhibited sample. The adsorption of the inhibitor was found to conform to the Langmuir isotherm with the standard adsorption free energy of -21.08 kJ mol{sup -1}.

  3. 2-Butyne-1,4-diol as a novel corrosion inhibitor for API X65 steel pipeline in carbonate/bicarbonate solution

    International Nuclear Information System (INIS)

    Sadeghi Meresht, E.; Shahrabi Farahani, T.; Neshati, J.

    2012-01-01

    Highlights: ► Corrosion of API 5L X65 is effectively reduced by the addition of the inhibitor. ► The techniques include weight loss, potentiodynamic polarization, EIS and AFM. ► 2-Butyne-1,4-diol acts as a mixed-type inhibitor. ► The adsorption of 2-butyne-1,4-diol obeys Langmuir adsorption isotherm. - Abstract: The inhibition effects of 2-butyne-1,4-diol on the corrosion susceptibility of grade API 5L X65 steel pipeline in 2 M Na 2 CO 3 /1 M NaHCO 3 solution were studied by electrochemical techniques and weight loss measurements. The results indicated that this inhibitor was a mixed-type inhibitor, with a maximum percentage inhibition efficiency of approximately 92% in the presence of 5 mM inhibitor. Atomic force microscopy revealed that a protective film was formed on the surface of the inhibited sample. The adsorption of the inhibitor was found to conform to the Langmuir isotherm with the standard adsorption free energy of −21.08 kJ mol −1 .

  4. Isolation of endosulfan sulfate-degrading Rhodococcus koreensis strain S1-1 from endosulfan contaminated soil and identification of a novel metabolite, endosulfan diol monosulfate

    Energy Technology Data Exchange (ETDEWEB)

    Ito, Koji; Kawashima, Fujimasa [Department of Applied Biology and Chemistry, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo, 156-8502 (Japan); Organochemicals Division, National Institute for Agro-Environmental Sciences, 3-1-3 Kannondai, Tsukuba, Ibaraki, 305-8604 (Japan); Takagi, Kazuhiro, E-mail: ktakagi@affrc.go.jp [Department of Applied Biology and Chemistry, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo, 156-8502 (Japan); Organochemicals Division, National Institute for Agro-Environmental Sciences, 3-1-3 Kannondai, Tsukuba, Ibaraki, 305-8604 (Japan); Kataoka, Ryota [Department of Environmental Science, University of Yamanashi, 41-4-37 Takeda, Kofu, Yamanashi (Japan); Kotake, Masaaki [Graduate School of Agricultural Science, Tohoku University, Aoba-ku, Sendai 981-8555 (Japan); Kiyota, Hiromasa [Graduate School of Environmental & Life Science, Okayama University, 1-1-1 Tsushima-naka, Kita-ku, Okayama 700-8530 (Japan); Yamazaki, Kenichi [Organochemicals Division, National Institute for Agro-Environmental Sciences, 3-1-3 Kannondai, Tsukuba, Ibaraki, 305-8604 (Japan); Sakakibara, Futa [Organochemicals Division, National Institute for Agro-Environmental Sciences, 3-1-3 Kannondai, Tsukuba, Ibaraki, 305-8604 (Japan); The Japan Society for the Promotion of Science(JSPS), 1-8 Chiyoda-ku, Tokyo (Japan); Okada, Sanae [Department of Applied Biology and Chemistry, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo, 156-8502 (Japan)

    2016-05-13

    An aerobic endosulfan sulfate-degrading bacterium, Rhodococcus koreensis strain S1-1, was isolated from soil to which endosulfan had been applied annually for more than 10 years until 2008. The strain isolated in this work reduced the concentration of endosulfan sulfate (2) from 12.25 μM to 2.11 μM during 14 d at 30 °C. Using ultra performance liquid chromatography-electrospray ionization-mass spectroscopy (UPLC-ESI-MS), a new highly water-soluble metabolite possessing six chlorine atoms was found to be endosulfan diol monosulfate (6), derived from 2 by hydrolysis of the cyclic sulfate ester ring. The structure of 6 was elucidated by chemical synthesis of the candidate derivatives and by HR-MS and UPLC-MS analyses. Therefore, it was suggested that the strain S1-1 has a new metabolic pathway of 2. In addition, 6 was expected to be less toxic among the metabolites of 1 because of its higher water-solubility. -- Highlights: •A novel endosulfan sulfate-degrading bacterium was isolated and named strain S1-1. •Strain S1-1 degraded endosulfan sulfate into a novel metabolite endosulfan diol monosulfate. •Endosulfan diol monosulfate showed higher polarity than other known metabolites of endosulfan. •We proposed the plausible metabolic pathway of endosulfan in terms of organic chemistry.

  5. Isolation of endosulfan sulfate-degrading Rhodococcus koreensis strain S1-1 from endosulfan contaminated soil and identification of a novel metabolite, endosulfan diol monosulfate

    International Nuclear Information System (INIS)

    Ito, Koji; Kawashima, Fujimasa; Takagi, Kazuhiro; Kataoka, Ryota; Kotake, Masaaki; Kiyota, Hiromasa; Yamazaki, Kenichi; Sakakibara, Futa; Okada, Sanae

    2016-01-01

    An aerobic endosulfan sulfate-degrading bacterium, Rhodococcus koreensis strain S1-1, was isolated from soil to which endosulfan had been applied annually for more than 10 years until 2008. The strain isolated in this work reduced the concentration of endosulfan sulfate (2) from 12.25 μM to 2.11 μM during 14 d at 30 °C. Using ultra performance liquid chromatography-electrospray ionization-mass spectroscopy (UPLC-ESI-MS), a new highly water-soluble metabolite possessing six chlorine atoms was found to be endosulfan diol monosulfate (6), derived from 2 by hydrolysis of the cyclic sulfate ester ring. The structure of 6 was elucidated by chemical synthesis of the candidate derivatives and by HR-MS and UPLC-MS analyses. Therefore, it was suggested that the strain S1-1 has a new metabolic pathway of 2. In addition, 6 was expected to be less toxic among the metabolites of 1 because of its higher water-solubility. -- Highlights: •A novel endosulfan sulfate-degrading bacterium was isolated and named strain S1-1. •Strain S1-1 degraded endosulfan sulfate into a novel metabolite endosulfan diol monosulfate. •Endosulfan diol monosulfate showed higher polarity than other known metabolites of endosulfan. •We proposed the plausible metabolic pathway of endosulfan in terms of organic chemistry.

  6. Infrared, Raman and density functional characterization and structural study of 2-Nitro-2-phenyl-propane-1,3-diol

    Science.gov (United States)

    Kaya, Mehmet Fatih; Bağlayan, Özge; Kaya, Esma Güneş; Alver, Özgür

    2017-12-01

    Nitro compound and nitro derivatives are industrially important to produce rubber and agricultural chemicals. In this study, one of the promising derivatives of nitro compound 2-Nitro-2-phenyl-propane-1,3-diol (2NPP) is examined in detail. FT-Infrared and dispersive Raman spectra of 2NPP (C9H11NO4) were respectively recorded in 4000-10 cm-1 and 4000-100 cm-1. The bond distances and angles, conformational distributions, vibrational frequencies and the assignment of each mode, some thermodynamic parameters and reactivity descriptors: total energy, hardness, chemical potential, electrophilicity index, electronegativity, frontier orbitals energy gap of 2NPP were investigated by using DFT/B3LYP method with 6-31++G (d,p) basis set. In order to locate the global minimum on the potential energy surface of 2NPP, a beforehand conformational examinations were carried out using Spartan 10 along with semi-emprical PM6 method. The results of conformational analyses showed that there are five possible conformations having energies under 2 kcal/mol. Comparison of the theoretical and experimental results clearly indicates that density functional hybrid B3LYP/6-31++G (d,p) level of theory can be used to predict vibrational frequencies and structural parameters of 2NPP. Further, C1 geometry is considered to be the global minimum conformation of 2NPP.

  7. Efficiency of 1,9- Nonane-diol-diacrylate as a radiation vulcanization accelerator for natural rubber latex

    International Nuclear Information System (INIS)

    Haque, M.E.

    2003-09-01

    The efficiency of 1,9- Nonane-diol-diacrylate (NDDA) as a radiation vulcanization accelerator (RVA) for natural rubber latex (NRL) was investigated. Both gamma rays and electron beam (EB) were used for vulcanizing NRL with NDDA. The radiation dose of gamma rays, concentration of NDDA required to vulcanize the latex were optimized. 20 kGy radiation dose of gamma rays and 5 phr concentration of NDDA were found optimum to get maximum tensile and related properties. NRL was vulcanized under EB to find out the optimum condition of irradiation with this RVA. The defoamer concentrations, length of irradiation time under EB, concentration of RVA were optimizer by changing various parameters of the EB machine with a constant set of the others. 0.2 phr defoamer concentration, 30 minutes irradiation time and 5 phr concentration of NDDA were found optimum for irradiation of NRL under the EB machine. Effect of low current and optimum volume of latex charged in the reaction vessel suitable for vulcanization at a time were found out. (author)

  8. Toxic mechanisms of 3-monochloropropane-1,2-diol on progesterone production in R2C rat leydig cells.

    Science.gov (United States)

    Sun, Jianxia; Bai, Shun; Bai, Weibin; Zou, Feiyan; Zhang, Lei; Su, Zhijian; Zhang, Qihao; Ou, Shiyi; Huang, Yadong

    2013-10-16

    3-Monochloropropane-1,2-diol (3-MCPD) is a well-known food processing contaminant that has been shown to impede the male reproductive function. However, its mechanism of action remains to be elucidated. In this study, the effects of 3-MCPD on progesterone production were investigated using R2C Leydig cells. 3-MCPD caused concentration-dependent inhibition of cell viability at the IC25, IC50, and IC75 levels of 1.027, 1.802, and 3.160 mM, respectively. Single cell gel/comet assay and atomic force microscopy assay showed that 3-MCPD significantly induced early apoptosis. In addition, 3-MCPD significantly reduced progesterone production by reducing the expression of cytochrome P450 side-chain cleavage enzyme, steroidogenic acute regulatory protein, and 3β-hydroxysteroid dehydrogenase in R2C cells. The change in steroidogenic acute regulatory protein expression was highly consistent with progesterone production. Furthermore, the mitochondrial membrane potential and cAMP significantly decreased.

  9. Structural and vibrational study of a neurotransmitter molecule: Dopamine [4-(2-aminoethyl) benzene-1,2-diol].

    Science.gov (United States)

    Jha, Omkant; Yadav, T K; Yadav, R A

    2018-01-15

    Structural and vibrational studies for the most stable conformer of dopamine {4-(2-Aminoethyl) benzene-1, 2-diol} have been carried out at the DFT/B3LYP/6-311++G** level using the Gaussian 09 software. The IR and Raman spectra have been recorded and analyzed in light of the computed vibrational parameters using the DFT and the PEDs computed with the help of the GAR2PED software. Some of the fundamentals have considerably changed frequencies in going from benzene to dopamine. Except the rocking and wagging modes of the NH 2 group the other four modes are pure group modes. The rocking and wagging modes of the NH 2 group show mixing with the other modes. The two OH stretching vibrations are highly localized modes. The Kekule phenyl ring stretching mode is found to remain almost unchanged. The HOMO-LUMO study suggests the existence of charge transfer within the molecule and the energy gap supports the pharmacological active property of the dopamine molecule. The NBO analysis has been carried out to understand the proper and improper hydrogen bonding. Copyright © 2017. Published by Elsevier B.V.

  10. Dietary exposure of Hong Kong adults to fatty acid esters of 3-monochloropropane-1,2-diol.

    Science.gov (United States)

    Chung, H Y; Chung, Stephen W C; Chan, B T P; Ho, Yuk Yin; Xiao, Ying

    2013-01-01

    A total of 290 individual food samples were collected in Hong Kong, China, for 3-monochloropropane-1,2-diol (3-MCPD) fatty acid esters analysis. Most samples were processed food and in ready-to-eat form. The results show that the levels of 3-MCPD fatty acid esters were high in biscuits, fats and oils, snacks and Chinese pastry with mean bound 3-MCPD levels of 440, 390, 270 and 270 μg kg⁻¹, respectively. The dietary exposures to bound 3-MCPD of average and high adult consumers were estimated to be 0.20 and 0.53 μg kg bw⁻¹ day⁻¹, respectively. The primary toxicological concern of 3-MCPD fatty acid esters is its potential to release 3-MCPD in vivo during digestion in the gastrointestinal tract. 3-MCPD would affect the kidney, the central nervous system and the male reproductive system of rats. Assuming that 100% of the 3-MCPD was released from 3-MCPD fatty acid esters by hydrolysis in the digestive system, the dietary exposures to 3-MCPD for average and high adult consumers were only 10% and 26% of the provisional maximum tolerable daily intake (PMTDI) of 3-MCPD established by the Joint Food and Agriculture Organization/World Health Organization Expert Committee on Food Additives (JECFA) (2 μg kg bw⁻¹ day⁻¹), respectively. The results suggest that both average and high adult consumers are unlikely to experience major toxicological effects of 3-MCPD.

  11. Lack of effect on rat testicular organogenesis after in utero exposure to 3-monochloropropane-1,2-diol (3-MCPD).

    Science.gov (United States)

    El Ramy, Rosy; Ould Elhkim, Mostafa; Poul, Martine; Forest, Maguelone G; Leduque, Patrick; Le Magueresse-Battistoni, Brigitte

    2006-10-01

    3-Monochloropropane-1,2-diol (3-MCPD) is a food-born contaminant known to display toxic effects on male reproduction, producing infertility in rats and humans. Using the rat as a model, we investigated whether or not testicular organogenesis, which, in the rat species, occurs during the second half of gestation, was at particular risk regarding 3-MCPD toxicity. Pregnant rats were given daily doses of 5, 10 or 25 mg/kg BW of 3-MCPD from days 11.5-18.5 postcoitum (dpc). On 19.5 dpc, testes were removed from fetuses for histological examination and testosterone analysis. Eight genes were selected among the differentiation markers of testicular cell lineages, and their expression was studied by RT-PCR. The levels of 3-MCPD and its main metabolite, beta-chlorolactic acid, were assayed in fetal tissues and dam plasma. Our results show a statistically significant decrease in the mean body weight gain of pregnant rats treated with 10 and 25 mg/kg BW of 3-MCPD. Fetal testes exposed to 3-MCPD exhibited normal histology and produced testosterone at levels that were similar to controls. In addition, 3-MCPD did not alter gene expression in the fetal testes. This lack of effect occurred under conditions where 3-MCPD and beta-chlorolactic acid were found to readily cross the placental barrier and diffuse throughout the fetal tissues. Our findings indicate that 3-MCPD has minimal effect on rat testicular organogenesis.

  12. Optimization of palm oil physical refining process for reduction of 3-monochloropropane-1,2-diol (3-MCPD) ester formation.

    Science.gov (United States)

    Zulkurnain, Musfirah; Lai, Oi Ming; Tan, Soo Choon; Abdul Latip, Razam; Tan, Chin Ping

    2013-04-03

    The reduction of 3-monochloropropane-1,2-diol (3-MCPD) ester formation in refined palm oil was achieved by incorporation of additional processing steps in the physical refining process to remove chloroester precursors prior to the deodorization step. The modified refining process was optimized for the least 3-MCPD ester formation and acceptable refined palm oil quality using response surface methodology (RSM) with five processing parameters: water dosage, phosphoric acid dosage, degumming temperature, activated clay dosage, and deodorization temperature. The removal of chloroester precursors was largely accomplished by increasing the water dosage, while the reduction of 3-MCPD esters was a compromise in oxidative stability and color of the refined palm oil because some factors such as acid dosage, degumming temperature, and deodorization temperature showed contradictory effects. The optimization resulted in 87.2% reduction of 3-MCPD esters from 2.9 mg/kg in the conventional refining process to 0.4 mg/kg, with color and oil stability index values of 2.4 R and 14.3 h, respectively.

  13. Indole-3-acetic acid/diol based pH-sensitive biological macromolecule for antibacterial, antifungal and antioxidant applications.

    Science.gov (United States)

    G, Chitra; D S, Franklin; S, Sudarsan; M, Sakthivel; S, Guhanathan

    2017-02-01

    Indole-3-acetic acid (IAA)/diol based pH-sensitive biopolymeric hydrogels with tunable biological properties (cytotoxicity, anti-oxidant and anti-fungal) have been synthesized via condensation polymerization. The present study focused on the synthesis of heterocyclic hydrogel using citric acid (CA), indole-3-acetic acid (IAA) and diethylene glycol (DEG) by condensation polymerization. The hydrogels revealed a pH-sensitive swelling behaviour, with increased swelling in acidic media, then turns to decreased the swelling in the basic media. The hydrogel samples were tested for antifungal activity against Aspergillus fumigates, Rhizopusoryzae and Candida albicans at different concentrations using ketoconazole as positive control and DMSO as negative control for antifungal activity. Antioxidant activity increasing nature in DPPH than NO radical compared with rutin and confirmed non toxic property using cytotoxicity analysis. The biopolymeric hydrogels were characterized by Fourier transform infrared (FT-IR) spectroscopy, 1 H NMR, 13 C NMR, TGA, DSC followed by scanning electron microscopy (SEM). Such hydrogels with antioxidant properties is recommended for medical applications such as bandages, catheters, drains and tubes to prevent infection. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Formation of diastereomeric benzo[a]pyrene diol epoxide-guanine adducts in p53 gene-derived DNA sequences.

    Science.gov (United States)

    Matter, Brock; Wang, Gang; Jones, Roger; Tretyakova, Natalia

    2004-06-01

    G --> T transversion mutations in the p53 tumor suppressor gene are characteristic of smoking-related lung tumors, suggesting that these genetic changes may result from exposure to tobacco carcinogens. It has been previously demonstrated that the diol epoxide metabolites of bay region polycyclic aromatic hydrocarbons present in tobacco smoke, e.g., benzo[a]pyrene diol epoxide (BPDE), preferentially bind to the most frequently mutated guanine nucleotides within p53 codons 157, 158, 248, and 273 [Denissenko, M. F., Pao, A., Tang, M., and Pfeifer, G. P. (1996) Science 274, 430-432]. However, the methodology used in that work (ligation-mediated polymerase chain reaction in combination with the UvrABC endonuclease incision assay) cannot establish the chemical structures and stereochemical identities of BPDE-guanine lesions. In the present study, we employ a stable isotope-labeling HPLC-MS/MS approach [Tretyakova, N., Matter, B., Jones, R., and Shallop, A. (2002) Biochemistry 41, 9535-9544] to analyze the formation of diastereomeric N(2)-BPDE-dG lesions within double-stranded oligodeoxynucleotides representing p53 lung cancer mutational hotspots and their surrounding DNA sequences. (15)N-labeled dG was placed at defined positions within DNA duplexes containing 5-methylcytosine at all physiologically methylated sites, followed by (+/-)-anti-BPDE treatment and enzymatic hydrolysis of the adducted DNA to 2'-deoxynucleosides. Capillary HPLC-ESI(+)-MS/MS was used to establish the amounts of (-)-trans-N(2)-BPDE-dG, (+)-cis-N(2)-BPDE-dG, (-)-cis-N(2)-BPDE-dG, and (+)-trans-N(2)-BPDE-dG originating from the (15)N-labeled bases. We found that all four N(2)-BPDE-dG diastereomers were formed preferentially at the methylated CG dinucleotides, including the frequently mutated p53 codons 157, 158, 245, 248, and 273. The contributions of individual diastereomers to the total adducts number at a given site varied between 70.8 and 92.9% for (+)-trans-N(2)-BPDE-dG, 5.6 and 16.7% for

  15. A glucose-responsive pH-switchable bioelectrocatalytic sensor based on phenylboronic acid-diol specificity

    International Nuclear Information System (INIS)

    Gao, Peiyi; Wang, Zhihua; Yang, Lele; Ma, Tengfei; Yang, Ling; Guo, Qianqiong; Huang, Shasheng

    2015-01-01

    Graphical abstract: A pH-switchable bioelectrocatayltic sensor was developed, which exhibited an obvious anodic current in acidic conditions as “ON” state, yet a prohibited signal in alkaline conditions as “OFF” state. With the change of pH and/or the presence of glucose, our proposed biosensor produced the corresponding amplified signal, providing a better sensitivity. - Abstract: Aminophenylboronic acid moieties were covalently grafted onto mercaptobenzoic acid moieties, and glucose oxidase was then immobilized through boronic acid-diol specific recognition to form a pH-sensitive electrosensor switching between pH 5.8 and pH 8.0 base solution. Using potassium ferricyanide as electroactive probe, the response was intensified in acidic condition while hindered in alkaline condition. The sharp and stable contrast in current was performed alternately upon the change of pH like a “pH switch”. In the presence of glucose, the response to glucose was further amplified catalytically by glucose oxidase on “ON” state, while electron transfer was inhibited on “OFF” state. Furthermore, when our sensor was on “ON” state, it showed a good linearity ranging from 0 to 30 μmol L −1 of glucose, with a detection limit of 348 nmol L −1 (S/B = 3) and a dynamic range extending to 50 μmol L −1 . Glucose-responsive, pH-switchable and catalytically-amplified, our biosensor provided a new method for the detection of glucose in the form of pH switch in human serum sample, and was promising to more complicated environment

  16. Novel Magnetic Microprobe with Benzoboroxole-Modified Flexible Multisite Arm for High-Efficiency cis-Diol Biomolecule Detection.

    Science.gov (United States)

    Chen, Guosheng; Huang, Siming; Kou, Xiaoxue; Zhang, Jin'ge; Wang, Fuxin; Zhu, Fang; Ouyang, Gangfeng

    2018-03-06

    With regard to regulating a variety of biological events, including molecular recognition, signal transduction, cell adhesion, and immune response, cis-diol biomolecules, such as saccharides and glycoproteins, play vital roles. However, saccharides and glycoproteins in living systems usually exist in very low abundance, along with abundant interfering components. High-efficiency detection of saccharides and glycoproteins is a challenging yet highly impactful area of research. Herein, we reported a novel magnetic microprobe with a benzoboroxole-modified flexible multisite arm (PEG 2000-grafted PAMAM dendrimers; the microprobe was denoted as BFMA-MNP) for high-efficiency saccharides detection. The extraction capacity was significantly improved by ∼2 orders of magnitude, because of the integration of the enhanced hydrophilicity and multivalency effects in benzoboroxoles and the enhanced accessibility of the binding sites within the PEG 2000-grafted PAMAM dendrimers. As a result, the proposed approach possessed several advantages, compared with previous boronic acid-based methods, including ultrahigh sensitivity (limit of detection was <1 ng/mL), wide linear range (ranged from 0.5 μM to 2000 μM), and applicable in physiological pH condition. Furthermore, we established a general BFMA-MNP/glycoproteins/AuNPs sandwich assay to realize the visual glycoprotein qualitative screening for the first time. The unique sandwich assay possessed the dual nature of the magnetic separation by BFMA-MNPs and specific coloration by citrate-coated AuNPs. This visual sandwich assay enabled fast differentiation of the existence of glycoproteins in complicated samples without any advanced instruments. We believe the proposed BFMA-MNP microprobe herein will advance the ideas to detect and identify trace saccharides and glycoproteins in important fields such as glycomics and glycoproteomics.

  17. Altered susceptibility of an obese rat model to 13-week subchronic toxicity induced by 3-monochloropropane-1,2-diol.

    Science.gov (United States)

    Toyoda, Takeshi; Cho, Young-Man; Akagi, Jun-Ichi; Mizuta, Yasuko; Matsushita, Kohei; Nishikawa, Akiyoshi; Imaida, Katsumi; Ogawa, Kumiko

    2017-01-01

    3-Monochloropropane-1,2-diol (3-MCPD) is a heat-induced food contaminant that has been shown to be a nongenotoxic renal carcinogen. Although the toxicity of 3-MCPD has been widely investigated for decades, there is a further concern that 3-MCPD might exert more potent toxicity in high-risk population with underlying diseases such as hyperlipidemia associated with obesity. In the present study, we performed a 13-week subchronic toxicity study for 3-MCPD using an obesity rat model to investigate the differences in susceptibility between obese and normal individuals. Male F344 and obese Zucker (lean and fatty) rats were administered 0, 9, 28.5, 90, 285, or 900 ppm 3-MCPD in drinking water for 13 weeks. 3-MCPD treatment decreased body weight gain, increased relative kidney weights, induced anemia, and induced epithelial cell necrosis in epididymal ducts in all 3 strains. The degrees of epididymal damage were higher in F344 and lean rats than in fatty rats, while renal toxicity was most potent in F344 rats and comparable in lean and fatty rats. In contrast, the hematology data indicated that anemia was worse in fatty rats than in F344 and lean rats, and a significant decrease in hematopoietic cells in the bone marrow was observed only in fatty rats. The no-observed-adverse-effect level was estimated to be 28.5 ppm in all 3 strains for 3-MCPD. These results suggested that obese Zucker rats may be more susceptible to 3-MCPD-dependent toxicity in the hematopoietic tissues than their lean counterparts.

  18. Partial molar volumes of organic solutes in water. XXIV. Selected alkane-α,ω-diols at temperatures T = 298 K to 573 K and pressures up to 30 MPa

    International Nuclear Information System (INIS)

    Cibulka, Ivan; Hnědkovský, Lubomír

    2013-01-01

    Highlights: • Standard molar volumes of three alkane-α,ω-diols (C 5 , C 8 , C 9 ) in water are presented. • Data were obtained in the range T from (298 to 573) K and p up to 30 MPa. • Dependences on carbon atom number, temperature, and pressure are analysed. -- Abstract: Density data for dilute aqueous solutions of three alkane-α,ω-diols (pentane-1,5-diol, octane-1,8-diol, nonane-1,9-diol) are presented together with standard molar volumes (partial molar volumes at infinite dilution) calculated from the experimental data. The measurements were performed at temperatures from T = 298 K up to T = 573 K. Experimental pressures were slightly above the saturation vapour pressure of water, and (15 and 30) MPa. The data were obtained using a high-temperature high-pressure flow vibrating-tube densimeter. Measured standard molar volumes were combined with data previously published for other members of the homologous series and discussed. Experimental standard molar volumes were correlated as a function of temperature and pressure using an empirical polynomial function. Dependences of standard molar volumes on temperature and pressure were analysed. Contributions of the methylene group to the standard molar volume were also evaluated and discussed

  19. Steviamine, a new class of indolizidine alkaloid [(1R,2S,3R,5R,8aR-3-hydroxymethyl-5-methyloctahydroindolizine-1,2-diol hydrobromide

    Directory of Open Access Journals (Sweden)

    Amber L. Thompson

    2009-11-01

    Full Text Available X-ray crystallographic analysis of the title hydrobromide salt, C10H20N+·Br−, of (1R,2S,3R,5R,8aR-3-hydroxymethyl-5-methyloctahydroindolizine-1,2-diol defines the absolute and relative stereochemistry at the five chiral centres in steviamine, a new class of polyhydroxylated indolizidine alkaloid isolated from Stevia rebaudiana (Asteraceae leaves. In the crystal structure, molecules are linked by intermolecular O—H...Br and N—H...Br hydrogen bonds, forming double chains around the twofold screw axes along the b-axis direction. Intramolecular O—H...O interactions occur.

  20. Multipoint attachment to a support protects enzyme from inactivation by organic solvents: alpha-Chymotrypsin in aqueous solutions of alcohols and diols.

    Science.gov (United States)

    Mozhaev, V V; Sergeeva, M V; Belova, A B; Khmelnitsky, Y L

    1990-03-25

    Inactivation of alpha-chymotrypsin in aqueous solutions of alcohols and diols proceeds both reversibly and irreversibly. Reversible loss of the specific enzyme activity results from conformational changes (unfolding) of the enzyme detected by fluorescence spectroscopy. Multipoint covalent attachment to the matrix of polyacryl-amide gel by copolymerization method stabilizes alpha-chymotrypsin from denaturation by alcohols, the stabilizing effect increasing with the number of bonds between the protein and the support. Immobilization protects the enzyme also from irreversible inactivation by organic solvents resulting from bimolecular aggregation and autolysis.

  1. Hydroformylation of olefins and reductive carbonylation of aryl halides with syngas formed ex situ from dehydrogenative decarbonylation of hexane-1,6-diol

    DEFF Research Database (Denmark)

    Christensen, Stig Holden; Olsen, Esben Paul Krogh; Rosenbaum, Jascha

    2014-01-01

    A variety of primary alcohols have been investigated as convenient substrates for the ex situ delivery of carbon monoxide and molecular hydrogen in a two-chamber reactor. The gaseous mixture is liberated in one chamber by an iridium-catalysed dehydrogenative decarbonylation of the alcohol...... and then consumed in the other chamber in either a rhodium-catalysed hydroformylation of olefins or a palladium-catalysed reductive carbonylation of aryl halides. Hexane-1,6-diol was found to be the optimum alcohol for both reactions where moderate to excellent yields were obtained of the product aldehydes...

  2. Development of analytical methods for the gas chromatographic determination of 1,2-epoxy-3-butene, 1,2:3,4-diepoxybutane, 3-butene-1,2-diol, 3,4-epoxybutane-1,2-diol and crotonaldehyde from perfusate samples of 1,3-butadiene exposed isolated mouse and rat livers

    Energy Technology Data Exchange (ETDEWEB)

    Bhowmik, S.; Schuster, A.; Filser, J.G.

    2003-07-01

    Mutagenicity and carcinogenicity of 1,3-butadiene (BD) highly probably results from epoxide metabolites as 1,2-epoxy-3-butene (EB), 1,2:3,4-diepoxybutane (DEB) and 3,4-epoxybutane-1,2-diol (EBD). A further metabolite crotonaldehyde (CA) has also been discussed to be relevant. So far, in BD exposed rodents only EB and DEB concentrations had been quantified. However, the methods used were either not very sensitive or instrumentally expensive. Therefore, the goal of the present work was to establish simple analytical methods selective and sensitive enough to determine all of these compounds and a further secondary BD intermediate, 3-butene-1,2-diol (B-diol), in BD exposed rodent livers. The once-through perfused liver system was chosen for testing the applicability of the methods to be developed, since it enables BD exposures of this quantitatively most relevant metabolising organ near to the in-vivo situation. All the metabolites were extracted from the aqueous perfusion medium and analysed using a gas chromatograph equipped with a mass selective detector (GC/MS) in the PCI mode. (orig.)

  3. Transition from androgenic to neurosteroidal action of 5α-androstane-3α, 17β-diol through the type A γ-aminobutyric acid receptor in prostate cancer progression.

    Science.gov (United States)

    Xia, Ding; Lai, Doan V; Wu, Weijuan; Webb, Zachary D; Yang, Qing; Zhao, Lichao; Yu, Zhongxin; Thorpe, Jessica E; Disch, Bryan C; Ihnat, Michael A; Jayaraman, Muralidharan; Dhanasekaran, Danny N; Stratton, Kelly L; Cookson, Michael S; Fung, Kar-Ming; Lin, Hsueh-Kung

    2018-04-01

    Androgen ablation is the standard of care prescribed to patients with advanced or metastatic prostate cancer (PCa) to slow down disease progression. Unfortunately, a majority of PCa patients under androgen ablation progress to castration-resistant prostate cancer (CRPC). Several mechanisms including alternative intra-prostatic androgen production and androgen-independent androgen receptor (AR) activation have been proposed for CRPC progression. Aldo-keto reductase family 1 member C3 (AKR1C3), a multi-functional steroid metabolizing enzyme, is specifically expressed in the cytoplasm of PCa cells; and positive immunoreactivity of the type A γ-aminobutyric acid receptor (GABA A R), an ionotropic receptor and ligand-gated ion channel, is detected on the membrane of PCa cells. We studied a total of 72 radical prostatectomy cases by immunohistochemistry, and identified that 21 cases exhibited positive immunoreactivities for both AKR1C3 and GABA A R. In the dual positive cancer cases, AKR1C3 and GABA A R subunit α 1 were either expressed in the same cells or in neighboring cells. Among several possible substrates, AKR1C3 reduces 5α-dihydrotesterone (DHT) to form 5α-androstane-3α, 17β-diol (3α-diol). 3α-diol is a neurosteroid that acts as a positive allosteric modulator of the GABA A R in the central nervous system (CNS). We examined the hypothesis that 3α-diol-regulated pathological effects in the prostate are GABA A R-dependent, but are independent of the AR. In GABA A R-positive, AR-negative human PCa PC-3 cells, 3α-diol significantly stimulated cell growth in culture and the in ovo chorioallantoic membrane (CAM) xenograft model. 3α-diol also up-regulated expression of the epidermal growth factor (EGF) family of growth factors and activation of EGF receptor (EGFR) and Src as measured by quantitative polymerase chain reaction and immunoblotting, respectively. Inclusion of GABA A R antagonists reversed 3α-diol-stimulated tumor cell growth, expression of EGF

  4. The Analysis Methods Of 3-Monochloropropane-1,2-Diol and Glycydyl Esters in Foods, Mitigation Studies, and Current Developments About their Effects on Health

    Directory of Open Access Journals (Sweden)

    Aslı Yıldırım

    2017-12-01

    Full Text Available Chloropropanols are known as undesired food contaminants liberated during the processing of various food products. When the adverse effects of chloropropanols, especially 3-monochloropropane-1,2-diol (3-MCPD, 2-monochloropropane-1,3-diol (2-MCPD and glycidols along with their esters were first understood, the studies about the detection and mitigation of these compounds were accelerated. 3-MCPD, which was detected in food products in higher amounts when compared to other chloropropanols, usually occurs during refining process of vegetable oils, especially in deodorisation step. The novel methods in terms of the analysis of 3-MCPD and other chloropropanols are continuously updated. However, there are two basic methods today namely direct and indirect methods. Direct methods enable to detect all of the esters individually, yet, due to the necessity of a huge number of reference standards, indirect methods are currently more preferred. The first essential step of reducing chloropropanols in food products is to determine the proper analysis method. In this review, general information, new developments in analysis methods, mitigation studies and the toxigolocial data about various chloropropanols were summarized.

  5. Pyriculins A and B, two monosubstituted hex-4-ene-2,3-diols and other phytotoxic metabolites produced by Pyricularia grisea isolated from buffelgrass (Cenchrus ciliaris).

    Science.gov (United States)

    Masi, Marco; Meyer, Susan; Górecki, Marcin; Mandoli, Alessandro; Di Bari, Lorenzo; Pescitelli, Gennaro; Cimmino, Alessio; Cristofaro, Massimo; Clement, Suzette; Evidente, Antonio

    2017-11-01

    Pyricularia grisea has been identified as a foliar pathogen on buffelgrass (Cenchrus ciliaris) in North America and was studied as a potential source of phytotoxins for buffelgrass control. Two monosubstituted hex-4-ene-2,3-diols, named pyriculins A and B, were isolated from its culture filtrate organic extract together with (10S,11S)-(-)-epipyriculol, trans-3,4-dihydro-3,4,8-trihydroxy-1(2H)-napthalenone, and (4S)-(+)-isosclerone. Pyriculins A and B were characterized by spectroscopic (essentially nuclear magnetic resonance [NMR], High-resolution electrospray ionization mass spectrometry [HRESIMS]) and chemical methods such as (4E)-1-(4-hydroxy-1,3-dihydroisobenzofuran-1-yl)hex-4-ene-2,3-diols. The relative and absolute configuration of these compounds was determined by a combination of spectroscopic (NMR, electronic circular dichroism [ECD]) and computational tools. When bioassayed in a buffelgrass coleoptile and radicle elongation test, (10S,11S)-(-)-epipyriculol proved to be the most toxic compound. Seed germination was much reduced and slowed with respect to the control and radicles failed to elongate. All five compounds delayed germination, but only (10S,11S)-(-)-epipyriculol was able to prevent radicle development of buffelgrass seedlings. It had no effect on coleoptile elongation, while the other four compounds caused significantly increased coleoptile development relative to the control. © 2017 Wiley Periodicals, Inc.

  6. Diacyltransferase Activity and Chain Length Specificity of Mycobacterium tuberculosis PapA5 in the Synthesis of Alkyl β-Diol Lipids

    Energy Technology Data Exchange (ETDEWEB)

    Touchette, Megan H.; Bommineni, Gopal R.; Delle Bovi, Richard J.; Gadbery, John; Nicora, Carrie D.; Shukla, Anil K.; Kyle, Jennifer E.; Metz, Thomas O.; Martin, Dwight W.; Sampson, Nicole S.; Miller, W. T.; Tonge, Peter J.; Seeliger, Jessica C.

    2015-09-08

    Although classified as Gram-positive bacteria, Corynebacterineae possess an asymmetric outer membrane that imparts structural and thereby physiological similarity to more distantly related Gram-negative bacteria. Like lipopolysaccharide in Gram-negative bacteria, lipids in the outer membrane of Corynebacterineae have been associated with the virulence of pathogenic species such as Mycobacterium tuberculosis (Mtb). For example, Mtb strains that lack long, branched-chain alkyl esters known as dimycocerosates (DIMs) are significantly attenuated in model infections. The resultant interest in the biosynthetic pathway of these unusual virulence factors has led to the elucidation of many of the steps leading to the final esterification of the alkyl beta-diol, phthiocerol, with branched-chain fatty acids know as mycocerosates. PapA5 is an acyltransferase implicated in these final reactions. We here show that PapA5 is indeed the terminal enzyme in DIM biosynthesis by demonstrating its dual esterification activity and chain-length preference using synthetic alkyl beta-diol substrate analogues. Applying these analogues to a series of PapA5 mutants, we also revise a model for the substrate binding within PapA5. Finally, we demonstrate that the Mtb Ser/Thr kinase PknB modifies PapA5 on three Thr residues, including two (T196, T198) located on an unresolved loop. These results clarify the DIM biosynthetic pathway and suggest possible mechanisms by which DIM biosynthesis may be regulated by the post-translational modification of PapA5.

  7. Sterol synthesis. A novel reductive rearrangement of an alpha,beta-unsaturated steroidal epoxide; a new chemical synthesis of 5alpha-cholest-8(14)-en-3beta, 15alpha-diol.

    Science.gov (United States)

    Parish, E J; Schroepfer, G J

    1977-04-01

    Reduction of 3beta-benzoyloxy-14alpha,15alpha-epoxy-5alpha-cholest-7-ene with either lithium triethylboro-hydride or lithium aluminum hydride (4 molar excess) gave 5-alpha-cholest-8(14)-en-3beta,15alpha-diol in high yield. Reduction of the epoxy ester with lithium triethylborodeuteride or lithium aluminum deuteride (4 molar excess) gave [7alpha-2-H]-5alpha-cholest-8(14)-en-3beta,15alpha-diol. Reduction of 2beta-benzoyloxy-14alpha,15alpha-epoxy-5alpha-cholest-7-ene with a large excess (24 molar excess) of lithium aluminum hydride gave, in addition to the expected 5alpha-cholest-8(14)-en-3beta,15alpha-diol, a significant yield (33%) of 5alpha-cholest-8(14)-en-3beta-o1. Reduction of the epoxy ester with a large excess (24 molar excess) of lithium aluminum deuteride gave [7alpha-2H]-5alpha-cholest-8(14)-en-3beta,15alpha-diol and 5alpha-cholest-8(14)-en-3beta-o1 which contained two atoms of stably bound deuterium.

  8. Transfer and control of molecular chirality in the 1 : 2 host-guest supramolecular complex consisting of Mg(II)bisporphyrin and chiral diols: the effect of H-bonding on the rationalization of chirality.

    Science.gov (United States)

    Ikbal, Sk Asif; Brahma, Sanfaori; Rath, Sankar Prasad

    2014-11-21

    A clear rationalization of the origin of chirality transfer from an optically active diol guest to an achiral Mg(ii)bisporphyrin host in a series of 1 : 2 host-guest supramolecular complexes has been reported here that has so far remained the most outstanding issue for the chirogenic process.

  9. BENZO[A]PYRENE AND ITS K-REGION DIOL INDUCE DNA DAMAGE IN C3H10T1/2C18 CELLS AS MEASURED BY THE ALKALINE SINGLE CELL GEL (COMET) ASSAY

    Science.gov (United States)

    160. Benzo[a]pyrene and its K-region diol induce DNA damage in C3HlOTl/2Cl8 cells as measured by the alkaline single cell gel (Comet) assay In a continuing series of studies on the genotoxicity ofK-region dihydrodiols of polycyclic aromatic hydrocarbons, we have repo...

  10. Ruthenium-complex catalyzed N-(cyclo)alkylation of aromatic amines with diols. Selective synthesis of N-(n-hydroixyalkyl)anilines of type PhNH(CH2)nOH and of some bioactive arylpiperazines,

    NARCIS (Netherlands)

    Koten, G. van; Abbenhuis, R.A.T.M.; Boersma, J.

    1998-01-01

    A new class of well-defined neutral mono-, and dicationic ruthenium(II) complexes containing a neutral terdentate donor system [C5H3N(CH2E)(2)-2,6] (E = PPh2 (PNP) or NMe2 (NN'N)) has been found effective as catalyst precursor in N-(cyclo)alkylation reactions of aromatic amines with diols

  11. Purification and identification of 4-allylbenzene-1,2-diol: an antilisterial and biofilm preventing compound from the leaves of Piper betle L. var Pachaikodi.

    Science.gov (United States)

    Kavitha, Sekar; HariKrishnan, Adhikesavan; Jeevaratnam, Kadirvelu

    2017-12-22

    Antibiotic-resistant food-borne Listeriosis has been rising with up to 30% mortality threat in humans since several decades. Hence, discovering antilisterial from the extracts of ethnomedicinal plants may be of value as a novel antidote. In our preceding study, we reported that ethanolic extract of Piper betle L. var Pachaikodi leaves exhibited antibacterial activity towards Listeria monocytogenes MTCC 657. Consequently in the present study, the bioactive molecule responsible for anti-Listeria activity was purified and identified as 4-allylbenzene-1,2-diol. This identified bioactive compound may have significance while used as antimicrobials and/or food additives in food processing sector as evidenced by dual action: biofilm inhibition and pore formation on cell membrane.

  12. Asymmetric Diels-Alder Reaction of α,β-Unsaturated Oxazolidin-2-one Derivatives Catalyzed by a Chiral Fe(III)-Bipyridine Diol Complex.

    Science.gov (United States)

    Li, Mao; Carreras, Virginie; Jalba, Angela; Ollevier, Thierry

    2018-02-16

    An asymmetric Fe III -bipyridine diol catalyzed Diels-Alder reaction of α,β-unsaturated oxazolidin-2-ones has been developed. Among various Fe II /Fe III salts, Fe(ClO 4 ) 3 ·6H 2 O was selected as the Lewis acid of choice. The use of a low catalyst loading (2 mol % of Fe(ClO 4 ) 3 ·6H 2 O and 2.4 mol % of Bolm's ligand) afforded high yields (up to 99%) and high enantiomeric excesses (up to 98%) of endo-cycloadducts for the Diels-Alder reaction between cyclopentadiene and substituted acryloyloxazolidin-2-ones. Other noncyclic dienes led to decreased enantioselectivities. A proposed model supports the observed stereoinduction.

  13. Bis(1,10-phenanthroline-κ2N,N′(sulfato-κ2O,O′cobalt(II propane-1,3-diol solvate

    Directory of Open Access Journals (Sweden)

    Kai-Long Zhong

    2010-03-01

    Full Text Available The title compound, [Co(SO4(C12H8N22]·C3H8O2, was obtained unexpectedly as a by-product during an attempt to synthesize a mixed-ligand complex of CoII with 1,10-phenanthroline (phen and melamine via a solvothermal reaction. The CoII metal ions are in a distorted octahedral coordination environment formed by four N atoms from two chelating phen ligands and two O atoms from a bidentate sulfate ligand. The two chelating N2C2 groups are almost perpendicular to each other [dihedral angle = 80.06 (8°]. A twofold rotation axis passes through the Co and S atoms, and also through the central C atom of the propane-1,3-diol solvent molecule. Intermolecular O—H...O hydrogen bonds help to stabilize the structure.

  14. Synthesis of omega-hydroxy carboxylic acids and alpha,omega-dimethyl ketones using alpha,omega-diols as alkylating agents.

    Science.gov (United States)

    Iuchi, Yosuke; Hyotanishi, Megumi; Miller, Brittany E; Maeda, Kensaku; Obora, Yasushi; Ishii, Yasutaka

    2010-03-05

    Synthesis of omega-hydroxy carboxylic acids and alpha,omega-dimethyl diketones was successfully achieved by using alpha,omega-diols as alkylating agents under the influence of an iridium catalyst. For example, the alkylation of butyl cyanoacetate with 1,13-tridecanediol in the presence of [IrCl(cod)](2) or [IrCl(coe)(2)](2) gave rise to butyl 2-cyano-15-hydroxypentadecanoate in good yield which is easily converted to cyclopentadecanolide (CPDL). In addition, the alkylation of acetone with 1,10-decanediol in the presence of [IrCl(cod)](2) and KOH resulted in an important muscone precursor, 2,15-hexadecanedione (HDDO), in good yield.

  15. Synthesis, properties and applications of biodegradable polymers derived from diols and dicarboxylic acids: from polyesters to poly(ester amide)s.

    Science.gov (United States)

    Díaz, Angélica; Katsarava, Ramaz; Puiggalí, Jordi

    2014-04-25

    Poly(alkylene dicarboxylate)s constitute a family of biodegradable polymers with increasing interest for both commodity and speciality applications. Most of these polymers can be prepared from biobased diols and dicarboxylic acids such as 1,4-butanediol, succinic acid and carbohydrates. This review provides a current status report concerning synthesis, biodegradation and applications of a series of polymers that cover a wide range of properties, namely, materials from elastomeric to rigid characteristics that are suitable for applications such as hydrogels, soft tissue engineering, drug delivery systems and liquid crystals. Finally, the incorporation of aromatic units and α-amino acids is considered since stiffness of molecular chains and intermolecular interactions can be drastically changed. In fact, poly(ester amide)s derived from naturally occurring amino acids offer great possibilities as biodegradable materials for biomedical applications which are also extensively discussed.

  16. High-throughput and sensitive analysis of 3-monochloropropane-1,2-diol fatty acid esters in edible oils by supercritical fluid chromatography/tandem mass spectrometry.

    Science.gov (United States)

    Hori, Katsuhito; Matsubara, Atsuki; Uchikata, Takato; Tsumura, Kazunobu; Fukusaki, Eiichiro; Bamba, Takeshi

    2012-08-10

    We have established a high-throughput and sensitive analytical method based on supercritical fluid chromatography (SFC) coupled with triple quadrupole mass spectrometry (QqQ MS) for 3-monochloropropane-1,2-diol (3-MCPD) fatty acid esters in edible oils. All analytes were successfully separated within 9 min without sample purification. The system was precise and sensitive, with a limit of detection less than 0.063 mg/kg. The recovery rate of 3-MCPD fatty acid esters spiked into oil samples was in the range of 62.68-115.23%. Furthermore, several edible oils were tested for analyzing 3-MCPD fatty acid ester profiles. This is the first report on the analysis of 3-MCPD fatty acid esters by SFC/QqQ MS. The developed method will be a powerful tool for investigating 3-MCPD fatty acid esters in edible oils. Copyright © 2012 Elsevier B.V. All rights reserved.

  17. 17a-Ethynyl-5a-androstane-3a, 17 β-diol Treatment of MNU-Induced Mammary Cancer in Rats

    International Nuclear Information System (INIS)

    Ahlem, C.N.; Frincke, J.M.; White, S.K.; Reading, Ch.L.; Trauger, R.J.; Lakshmanaswamy, R.

    2011-01-01

    N-methyl-N-nitrosourea (MNU) induces estrogen-dependent mammary tumors in female Lewis rats. We explored the antineoplastic activity of a synthetic androstane derivative, 17 a-ethynyl-5a-androstane-3a, 17β-diol (HE3235), as a single agent or in combination with docetaxel compared to tamoxifen, anastrazole, and docetaxel mono therapies against MNU-induced mammary tumors in female Lewis rats. Treatment with HE3235 alone rapidly reduced tumor burden, similar in effect to tamoxifen and anastrozole. The combination of HE3235 with docetaxel was more effective than any single agent, although without apparent toxicity. Only HE3235 or HE3235 plus docetaxel continued to suppress tumor growth after cessation of treatment. HE3235 treatment increased immunohistochemical markers of apoptosis and expression of pro apoptotic genes and estrogen receptor beta and decreased expression of anti apoptotic genes, androgen receptor, and estrogen receptor alpha. These data warrant clinical investigation of HE3235 for breast cancer treatment.

  18. Simultaneous determination of testosterone, 5α-androstan-17β-ol-3-one, 5α-androstane-3α,17β-diol and 5α-androstane-3β,17β-diol in plasma of adult male rabbits by radioimmunoassay

    International Nuclear Information System (INIS)

    Schanbacher, B.D.; Ewing, L.L.

    1975-01-01

    A simultaneous radioimmunoassay procedure for plasma testosterone (T), 5alpha-androstan-17beta-ol-3-one (DHT), 5alpha- androstane-3alpha,17beta-diol (3alphaol), and 5alpha-androstan- 3beta,17beta-diol (3betaol) is described in this report. Peripheral plasma concentrations of T, DHT, 3alphaol, and 3βol were 1.61 +- 0.26, 0.49 +- 0.15, 0.17 +- 0.03, and 0.24 +- 0.04 ng/ml, respectively, in adult male rabbits. In contrast, T, DHT, 3αol, and 3βol peripheral plasma concentrations in dexamethasone-treated castrate rabbits were 0.07 +- 0.001, 0.02 +- 0.01, 0.07 +- 0.01, and 0.05 +- 0.01 ng/ml, respectively. These results represent the first simultaneous measurement of T, DHT, 3αol, and 3βol in peripheral plasma of any male vertebrate. Moreover, we suggest that DHT, 3αol, and 3βol represent the unidentified immunoreactive material found in peripheral plasma of male rabbits by Falvo and Nalbandov. (auth)

  19. Voltammetric Response of Alizarin Red S-Confined Film-Coated Electrodes to Diol and Polyol Compounds: Use of Phenylboronic Acid-Modified Poly(ethyleneimine) as Film Component.

    Science.gov (United States)

    Takahashi, Shigehiro; Suzuki, Iwao; Ojima, Takuto; Minaki, Daichi; Anzai, Jun-Ichi

    2018-01-22

    Alizarin red S (ARS) was confined in layer-by-layer (LbL) films composed of phenylboronic acid-modified poly(ethyleneimine) (PBA-PEI) and carboxymethylcellulose (CMC) to study the voltammetric response to diol and polyol compounds. The LbL film-coated gold (Au) electrode and quartz slide were immersed in an ARS solution to uptake ARS into the film. UV-visible absorption spectra of ARS-confined LbL film suggested that ARS formed boronate ester (ARS-PBS) in the film. The cyclic voltammetry of the ARS-confined LbL film-coated electrodes exhibited oxidation peaks at -0.50 and -0.62 V, which were ascribed to the oxidation reactions of ARS-PBS and free ARS, respectively, in the LbL film. The peak current at -0.62 V increased upon the addition of diol or polyol compounds such as L-dopa, glucose, and sorbitol into the solution, depending on the concentration, whereas the peak current at -0.50 V decreased. The results suggest a possible use of ARS-confined PBA-PEI/CMC LbL film-coated Au electrodes for the construction of voltammetric sensors for diol and polyol compounds.

  20. Transformações químicas do (+-10b,14-diol-allo-aromadendrano, isolado de duguetia glabriuscula r. e. fries (r. e. fries (annonaceae e avaliações biológicas de alguns derivados obtidos Chemical modifications of (+-allo-aromadendrane-10b,14-diol isolated from duguetia glabriuscula r. e. fries (r. e. fries (annonaceae and biological evaluation of some obtained derivatives

    Directory of Open Access Journals (Sweden)

    Dênis Pires de Lima

    1997-12-01

    Full Text Available The sesquiterpene (+-allo-aromadendrane-10b-14-diol 1 was the lead compound to the preparation of several derivatives in order to test their biological activity against A. salina, C. sphaerospermum, E. coli and S. aureus. In this way the monoalcohols (+-viridiflorol 4, 9 and 11 were synthesized from 1 together with the acetal 6, the ketal 7, and the ketone 8. The oxirane 3 and nitrile 5 were also prepared using as an intermediate the tosylate derivative 2.

  1. Simultaneous determination of 3-monochloropropane-1,2-diol and acrylamide in food by gas chromatography-triple quadrupole mass spectrometry with coupled column separation.

    Science.gov (United States)

    Xu, Xiao-min; He, Hua-li; Zhu, Yan; Feng, Liang; Ying, Ying; Huang, Bai-fen; Shen, Hai-tao; Han, Jian-long; Ren, Yi-ping

    2013-01-14

    Both 3-monochloropropane-1,2-diol (3-MCPD) and acrylamide are contaminants found in heat-processed foods and their related products. A quantitative method was developed for the simultaneous determination of both contaminants in food by gas chromatography-triple quadrupole mass spectrometry (GC-MS/MS). The analytes were purified and extracted by the matrix solid-phase dispersion extraction (MSPDE) technique with Extrelut NT. A coupled column (a 3 m Innowax combined with a 30 m DB-5 ms) was developed to separate both compounds efficiently without derivatization. Triple quadrupole mass spectrometry in multiple reaction monitoring mode (MRM) was applied to suppress matrix interference and obtain good sensitivity in the determination of both analytes. The limit of detection (LOD) in the sample matrix was 5 μg kg(-1) for 3-MCPD or acrylamide. The average recoveries for 3-MCPD and acrylamide in different food matrices were 90.5-107% and 81.9-95.7%, respectively, with the intraday relative standard deviations (RSDs) of 5.6-13.5% and 5.3-13.4%, respectively. The interday RSDs were 6.1-12.6% for 3-MCPD and were 5.0-12.8% for acrylamide. Both contaminants were found in samples of bread, fried chips, fried instant noodles, soy sauce, and instant noodle flavoring. Neither 3-MCPD nor acrylamide was detected in the samples of dairy products (solid or liquid samples) and non-fried instant noodles. Copyright © 2012 Elsevier B.V. All rights reserved.

  2. IN0523 (Urs-12-ene-3α,24β-diol) a plant based derivative of boswellic acid protect Cisplatin induced urogenital toxicity

    International Nuclear Information System (INIS)

    Singh, Amarinder; Arvinda, S; Singh, Surjeet; Suri, Jyotsna; Koul, Surinder; Mondhe, Dilip M.; Singh, Gurdarshan; Vishwakarma, Ram

    2017-01-01

    The limiting factor for the use of Cisplatin in the treatment of different type of cancers is its toxicity and more specifically urogenital toxicity. Oxidative stress is a well-known phenomenon associated with Cisplatin toxicity. However, in Cisplatin treated group, abnormal animal behavior, decreased body weight, cellular and sub-cellular changes in the kidney and sperm abnormality were observed. Our investigation revealed that Cisplatin when administered in combination with a natural product derivative (Urs-12-ene-3α,24β-diol, labeled as IN0523) resulted in significant restoration of body weight and protection against the pathological alteration caused by Cisplatin to kidney and testis. Sperm count and motility were significantly restored near to normal. Cisplatin caused depletion of defense system i.e. glutathione peroxidase, catalase and superoxide dismutase, which were restored close to normal by treatment of IN0523. Reduction in excessive lipid peroxidation induced by Cisplatin was also found by treatment with IN0523. The result suggests that IN0523 is a potential candidate for ameliorating Cisplatin induced toxicity in the kidney and testes at a dose of 100 mg/kg p.o. via inhibiting the oxidative stress/redox status imbalance and may be improving the efflux mechanism. - Highlights: • Synthesis of a novel boswellic acid derivative (IN0523) • Counter oxidative stress induced due to Cisplatin • Protect against urogenital toxicity induced by Cisplatin

  3. Bis(1,10-phenanthroline-κ2N,N′(sulfato-κ2O,O′cobalt(II butane-2,3-diol monosolvate

    Directory of Open Access Journals (Sweden)

    Shi-Juan Wang

    2011-04-01

    Full Text Available In the title compound, [Co(SO4(C12H8N22]·C4H10O2, the Co2+ ion has a distorted octahedral coordination environment composed of four N atoms from two chelating 1,10-phenanthroline ligands and two O atoms from an O,O′-bidentate sulfate anion. The dihedral angle between the two chelating N2C2 groups is 83.48 (1°. The Co2+ ion, the S atom and the mid-point of the central C—C bond of the butane-2,3-diol solvent molecule are situated on twofold rotation axes. The molecules of the complex and the solvent molecules are held together by pairs of symmetry-related O—H...O hydrogen bonds with the uncoordinated O atoms of the sulfate ions as acceptors. The solvent molecule is disordered over two sets of sites with site occupancies of 0.40 and 0.60.

  4. Synthesis of boronate-functionalized organic-inorganic hybrid monolithic column for the separation of cis-diol containing compounds at low pH.

    Science.gov (United States)

    Zhao, Heqing; Lyu, Haixia; Qin, Wenfei; Xie, Zenghong

    2018-04-01

    In this work, an organic-inorganic hybrid boronate affinity monolithic column was prepared via "one-pot" process using 4-vinylphenylboronic acid as organic monomer and divinylbenzene as cross-linker. The effects of reaction temperature, solvents and composition of organic monomers on the column properties (e.g. morphology, permeability, and mechanical stability) were investigated. A series of test compounds including small neutral molecules, aromatic amines, and cis-diol compounds were used to evaluate the retention behaviors of the prepared hybrid monolithic column. The results demonstrated that the prepared hybrid monolith exhibited mixed-interactions including hydrophilicity, cation exchange, and boronate affinity interaction. The run-to-run, day-to-day and batch-to-batch reproducibilities of the prepared hybrid monolith for thiourea's retention time were satisfactory with the relative standard deviations (RSDs) less than 0.09, 1.45 and 4.05% (n = 3), respectively, indicating the effectiveness and practicability of the proposed method. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Serum Level of Antibody against Benzo[a]pyrene-7,8-diol-9,10-epoxide-DNA Adducts in People Dermally Exposed to PAHs

    Directory of Open Access Journals (Sweden)

    Lenka Borska

    2014-01-01

    Full Text Available Some specific antibodies indicate the presence of antigenic structures on DNA (DNA adducts that can play an important role in the process of mutagenesis and/or carcinogenesis. They indicate the presence of increased genotoxic potential (hazard prior to the formation of disease (primary prevention. The present study was focused on the serum level of benzo[a]pyrene 7,8-diol-9,10-epoxide-DNA adducts antibodies (anti-BPDE-DNA in psoriatic patients (n=55 dermally exposed to different levels of polycyclic aromatic hydrocarbons (PAHs. The general goal of the study was to contribute to better understanding of the value of the assumed biomarker (anti-BPDE-DNA for evaluation of the organism's answer to genotoxic exposure to PAHs. Elevated level of exposure to PAHs resulted in the increased level of anti-BPDE-DNA. However, almost all levels of anti-BPDE-DNA ranged within the field of low values. Both variants of GT (CCT-3% and CCT-5% induced higher expression of anti-BPDE-DNA in the group of nonsmokers. Significant relations between the level of anti-BPDE-DNA and PASI score, total duration of the therapy, or time of UVR exposure were not found. Further studies are needed to reduce interpretation uncertainty of this promising bioindicator.

  6. Production of 7,8-Dihydroxy Unsaturated Fatty Acids from Plant Oils by Whole Recombinant Cells Expressing 7,8-Linoleate Diol Synthase from Glomerella cingulata.

    Science.gov (United States)

    Seo, Min-Ju; Kang, Woo-Ri; Shin, Kyung-Chul; Oh, Deok-Kun

    2016-11-16

    The reaction conditions for the production of 7S,8S-dihydroxy-9,12(Z,Z)-octadecadienoic acid from linoleic acid by recombinant Escherichia coli expressing 7,8-linoleate diol synthase from Glomerella cingulata were optimized using response surface methodology. The optimal reaction conditions were pH 7.0, 18.6 °C, 10.8% (v/v) dimethyl sulfoxide, 44.9 g/L cells, and 14.3 g/L linoleic acid, with agitation at 256 rpm. Under these conditions, recombinant cells produced 7,8-dihydroxy unsaturated fatty acids in the range of 7.0-9.8 g/L from 14.3 g/L linoleic acid, 14.3 g/L oleic acid, and plant oil hydrolysates such as waste oil and olive oil containing 14.3 g/L linoleic acid or oleic acid. To the best of the authors' knowledge, this is the first report on the biotechnological production of 7,8-dihydroxy unsaturated fatty acids.

  7. 5-Androstene-3{beta},17{beta}-diol Promotes Recovery of Immature Hematopoietic Cells Following Myelosuppressive Radiation and Synergizes With Thrombopoietin

    Energy Technology Data Exchange (ETDEWEB)

    Aerts-Kaya, Fatima S.F.; Visser, Trudi P.; Arshad, Shazia [Department of Hematology, Erasmus University Medical Center, Rotterdam (Netherlands); Frincke, James; Stickney, Dwight R.; Reading, Chris L. [Harbor Therapeutics, Inc, San Diego, California (United States); Wagemaker, Gerard, E-mail: g.wagemaker@erasmusmc.nl [Department of Hematology, Erasmus University Medical Center, Rotterdam (Netherlands)

    2012-11-01

    Purpose: 5-Androstene-3{beta},17{beta}-diol (5-AED) stimulates recovery of hematopoiesis after exposure to radiation. To elucidate its cellular targets, the effects of 5-AED alone and in combination with (pegylated) granulocyte colony-stimulating factor and thrombopoietin (TPO) on immature hematopoietic progenitor cells were evaluated following total body irradiation. Methods and Materials: BALB/c mice were exposed to radiation delivered as a single or as a fractionated dose, and recovery of bone marrow progenitors and peripheral blood parameters was assessed. Results: BALB/c mice treated with 5-AED displayed accelerated multilineage blood cell recovery and elevated bone marrow (BM) cellularity and numbers of progenitor cells. The spleen colony-forming unit (CFU-S) assay, representing the life-saving short-term repopulating cells in BM of irradiated donor mice revealed that combined treatment with 5-AED plus TPO resulted in a 20.1-fold increase in CFU-S relative to that of placebo controls, and a 3.7 and 3.1-fold increase in comparison to 5-AED and TPO, whereas no effect was seen of Peg-G-CSF with or without 5-AED. Contrary to TPO, 5-AED also stimulated reconstitution of the more immature marrow repopulating (MRA) cells. Conclusions: 5-AED potently counteracts the hematopoietic effects of radiation-induced myelosuppression and promotes multilineage reconstitution by stimulating immature bone marrow cells in a pattern distinct from, but synergistic with TPO.

  8. [Field efficacy of repellent formulation containing para-menthane-3,8-diol and lemongrass against Culicoides pachymerus (Diptera: Ceratopogonidae) in Colombia].

    Science.gov (United States)

    Santamaría, Erika; Cabrera, Olga Lucía; Zipa, Yaneth; Pardo, Raúl Hernando

    2012-09-01

    Culicoides pachymerus is a major pest species for the inhabitants of the western Boyacá province of Colombia. The effect of a repellent lotion based on p-menthane-3,8-diol (16%) and lemongrass oil (2%) was evaluated against the bites of C. pachymerus. The repellent lotion was compared simultaneously with a control (no treatment) by human landing catches of C. pachymerus on the forearms of paired volunteers situated near human dwellings. Protection percentage and protection time for 3 to 6 h after repellent application was calculated. The test was repeated ten times. Only two females of C. pachymerus were collected on arms with the repellent treatment. In contrast, the mean biting rate in the untreated control was 47.7 midges/person/10 min. Mean protection percentage of the repellent was 100% up to 4 h and 99.5% up to 5 h. Protection time was 332.2 and 338.2 min in the two replicates where bites of C. pachymerus were confirmed. In the remaining eight replicates protection time exceeded the test duration. The repellent showed high efficacy against C. pachymerus, up to 5 h post-application.

  9. Synthesis, characterization and computational studies of 3-{(E)-[(2-hydroxyphenyl)imino]methyl}benzene-1,2-diol and molecular structure of its zwitterionic form

    Science.gov (United States)

    Ezeorah, Julius Chigozie; Ossai, Valentine; Obasi, Lawrence Nnamdi; Elzagheid, Mohamed I.; Rhyman, Lydia; Lutter, Michael; Jurkschat, Klaus; Dege, Necmi; Ramasami, Ponnadurai

    2018-01-01

    The Schiff base 3-{(E)-[(2-hydroxyphenyl)imino]methyl}benzene-1,2-diol was synthesized by the condensation of 2,3-dihydroxybenzaldehyde and 2-aminophenol in water at room temperature. The crystal was grown using two solvents (dry methanol and 60% methanol). The compound was characterized using elemental microanalysis, IR, NMR, UV spectroscopies and single-crystal X-ray diffraction crystallography. The X-ray structure reveals that the Schiff base crystallizes as a methanol solvate in dry methanol with triclinic crystal system, space group P-1 and Z = 2 in the unit cell and as a non-methanol solvate in 60% methanol with triclinic crystal system, space group P-1 and Z = 4 in the unit cell. The compound showed absorption bands at 272, 389, 473 and 602 nm in DMSO. These bands were assigned as π → π ∗, n → π∗ and n-σ∗ transitions. The 473 and 602 nm bands in DMSO reveal that the compound exists in tautomeric forms. The presence of N-H, C-O and Cdbnd N stretching vibrations in the IR spectrum indicates that the compound is zwitterionic in the solid state. This study was supplemented using density functional theory method.

  10. [Determination of 3-monochloropropane-1,2-diol in grease food by solid phase extraction-derivatization-gas chromatography-mass spectrometry].

    Science.gov (United States)

    Xiang, Xiaoling; Wang, Liyuan; Shen, Xianghong; Li, Chunsong; Shen, Jianfu; Wu, Pinggu

    2017-09-01

    To establish the method of determination of 3-monochloropropane-1,2-diol( 3-MCPD) in grease food by gas chromatography-mass spectrometry( GC-MS). 3-MCPD in grease food represented by bean paste was extracted by ultrasound,purified by alkaline earth solid phase extraction column,derivatived using phenylboronic acid( PBA) and detected by GC-MS. The linearity of 3-MCPD ranged from 1-100 ng/mL,with correlation coefficient at 0. 9993.The limits of quantitation( LOQ) in soy sauce,bean paste,pepper oil were 0. 6,0. 5 and7. 0 μg/kg and limits of detection( LOD) were 1. 9,1. 6 and 18. 8 μg/kg,respectively.Average recovery rate and relative standard deviation was 78. 3%-106. 7% and 1. 9%-11. 6%( n = 6), when 3-MCPD was added in grease food at 2. 5-1000 μg/kg. The method has good purification effect and the detection sensitivity and accuracy,and can be used for the determination of 3-MCPD in grease food.

  11. New Insights on Degumming and Bleaching Process Parameters on The Formation of 3-Monochloropropane-1,2-Diol Esters and Glycidyl Esters in Refined, Bleached, Deodorized Palm Oil.

    Science.gov (United States)

    Sim, Biow Ing; Muhamad, Halimah; Lai, Oi Ming; Abas, Faridah; Yeoh, Chee Beng; Nehdi, Imededdine Arbi; Khor, Yih Phing; Tan, Chin Ping

    2018-04-01

    This paper examines the interactions of degumming and bleaching processes as well as their influences on the formation of 3-monochloropropane-1,2-diol esters (3-MCPDE) and glycidyl esters in refined, bleached and deodorized palm oil by using D-optimal design. Water degumming effectively reduced the 3-MCPDE content up to 50%. Acid activated bleaching earth had a greater effect on 3-MCPDE reduction compared to natural bleaching earth and acid activated bleaching earth with neutral pH, indicating that performance and adsorption capacities of bleaching earth are the predominant factors in the removal of esters, rather than its acidity profile. The combination of high dosage phosphoric acid during degumming with the use of acid activated bleaching earth eliminated almost all glycidyl esters during refining. Besides, the effects of crude palm oil quality was assessed and it was found that the quality of crude palm oil determines the level of formation of 3-MCPDE and glycidyl esters in palm oil during the high temperature deodorization step of physical refining process. Poor quality crude palm oil has strong impact towards 3-MCPDE and glycidyl esters formation due to the intrinsic components present within. The findings are useful to palm oil refining industry in choosing raw materials as an input during the refining process.

  12. Measurement of micronuclei and internal dose in mice demonstrates that 3-monochloropropane-1,2-diol (3-MCPD) has no genotoxic potency in vivo.

    Science.gov (United States)

    Aasa, Jenny; Törnqvist, Margareta; Abramsson-Zetterberg, Lilianne

    2017-11-01

    In this study 3-monochloropropane-1,2-diol (3-MCPD), a compound that appears as contaminant in refined cooking oils, has been studied with regard to genotoxicity in vivo (mice) with simultaneous measurement of internal dose using state-of-the-art methodologies. Genotoxicity (chromosomal aberrations) was measured by flow cytometry with dual lasers as the frequency of micronuclei in erythrocytes in peripheral blood from BalbC mice intraperitoneally exposed to 3-MCPD (0, 50, 75, 100, 125 mg/kg). The internal doses of 3-MCPD in the mice were calculated from N-(2,3-dihydroxypropyl)-valine adducts to hemoglobin (Hb), quantified at very low levels by high-resolution mass spectrometry. Convincing evidence for absence of genotoxic potency in correlation to measured internal doses in the mice was demonstrated, despite relatively high administered doses of 3-MCPD. The results are discussed in relation to another food contaminant that is formed as ester in parallel to 3-MCPD esters in oil processing, i.e. glycidol, which has been studied previously by us in a similar experimental setup. Glycidol has been shown to be genotoxic, and in addition to have ca. 1000 times higher rate of adduct formation compared to that observed for 3-MCPD. The conclusion is that at simultaneous exposure to 3-MCPD and glycidol the concern about genotoxicity would be glycidol. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Carcinogenicity study of 3-monochloropropane-1, 2-diol (3-MCPD) administered by drinking water to B6C3F1 mice showed no carcinogenic potential.

    Science.gov (United States)

    Jeong, Jayoung; Han, Beom Seok; Cho, Wan-Seob; Choi, Mina; Ha, Chang-Su; Lee, Byoung-Seok; Kim, Yong-Bum; Son, Woo-Chan; Kim, Choong-Yong

    2010-09-01

    3-Monochloropropane-1, 2-diol (or 3-chloro-1,2-propanediol, 3-MCPD) is a well-known food processing contaminant found in a wide range of foods and ingredients. It has been classified as non-genotoxic carcinogen but its carcinogenic potential in the rodents has been controversial. The carcinogenicity to B6C3F1 mice by drinking water administration was assessed over a period of 104 weeks. Three groups, each comprising 50 male and 50 female mice received 3-MCPD at dosages of 30, 100 or 300 ppm up to Day 100 and 200 ppm onward (4.2, 14.3 and 33.0 mg/kg for males; 3.7, 12.2, and 31.0 mg/kg for females), were allocated. Survival was good, with at least 80% of males and 72% of females in each group surviving 104 weeks. Body weights and body weight gain were decreased in males and females receiving 200 ppm. Water and food consumptions of both sexes at 300/200 ppm were lowered. Emaciated or crouching position was observed for animals of both sexes exposed to 200 ppm. There were some differences in hematology and serum biochemistry compared with controls, although there was no histopathological evidence to support those changes. Histopathological examination did not reveal any neoplastic or non-neoplastic findings attributable to treatment with 3-MCPD. It is concluded that drinking water administration of 3-MCPD for 104 weeks revealed no evidence of carcinogenic potential.

  14. Experimental exposure to 3-monochloropropane-1,2-diol from the pre-puberty causes damage in sperm production and motility in adulthood

    Directory of Open Access Journals (Sweden)

    Kátia Cristina Melo Tavares Vieira

    2017-06-01

    Full Text Available 3-Monochloropropane-1,2-diol (3-MCPD is a food contaminant that can be formed during the thermic processing of various foodstuffs. Studies of reproductive toxicology of 3-MCPD are mainly concentrated in the evaluation of possible insults caused by exposure of adult animals. However, the prepuberty might be a period of different susceptibility to chemicals. The aim of this study was to evaluate the effects on reproductive endpoints of the 3-MCPD-exposure prepubertal male rats. Wistar male rats were assigned to 4 groups: control and exposed to 2.5; 5 or 10 mg kg-1 day-1 of 3-MCPD for 30 days by gavage. Testis and epididymis were used for sperm counts and histology analysis. Sertoli cell number and dynamic of the spermatogenesis were evaluated. Sperm were collected from the vas deferens for evaluation of the sperm motility and morphology. Number of sperm with progressive movement, number of Sertoli cells and germ cells and relative daily sperm production were decreased in the groups exposed to 5 and 10 mg kg-1 day-1 of 3-MCPD. Sperm morphology, testicular and epididymal histology were comparable among groups. Results show that 3-MCPD-exposure of rats from prepuberty might cause alterations in spermatogenesis and sperm maturation, similarly to exposure in adulthood.

  15. 3-Monochloropropane-1,2-diol (alpha-chlorohydrin) disrupts spermatogenesis and causes spermatotoxicity in males of the Egyptian fruit-bat (Rousettus aegyptiacus).

    Science.gov (United States)

    Mahmoud, Y I; Taha, A; Soliman, S

    2018-03-29

    We evaluated the sterilizing effect of 3-monochloropropane-1, 2-diol (3-MCPD) in male Egyptian fruit bats (Rousettus aegyptiacus). We used three groups. One was treated with 70 mg/kg 3-MCPD for 4 days. The second group was treated with 3-MCPD as a bait formulation (known concentration of 3-MCPD mixed with a known amount of food). The third group was untreated controls. We compared the weights of the reproductive organs, histology of the testes, occurrence of spermatogenesis, and the count, motility and abnormalities of epididymal sperm of treated males with those of the untreated control group. 3-MCPD caused significantly decreased weights of reproductive organs, several testicular histological alterations and spermatogenic arrest accompanied by significant decreases in sperm count and motility, and significantly increased number of abnormal sperm. 3-MCPD bait was readily accepted by the animals. 3-MCPD, even in low doses and after limited exposure, disrupted spermatogenesis in males of the Egyptian fruit bat. Our findings have potential value for public health and agricultural authorities, and for vertebrate pest managers. 3-MCPD may have application for control of this pest.

  16. The effects of physical refining on the formation of 3-monochloropropane-1,2-diol esters in relation to palm oil minor components.

    Science.gov (United States)

    Zulkurnain, Musfirah; Lai, Oi Ming; Latip, Razam Abdul; Nehdi, Imededdine Arbi; Ling, Tau Chuan; Tan, Chin Ping

    2012-11-15

    The formation of 3-monochloropropane-1,2-diol (3-MCPD) esters in refined palm oil during deodorisation is attributed to the intrinsic composition of crude palm oil. Utilising D-optimal design, the effects of the degumming and bleaching processes on the reduction in 3-MCPD ester formation in refined palm oil from poor-quality crude palm oil were studied relative to the palm oil minor components that are likely to be their precursors. Water degumming remarkably reduced 3-MCPD ester formation by up to 84%, from 9.79 mg/kg to 1.55 mg/kg. Bleaching with synthetic magnesium silicate caused a further 10% reduction, to 0.487 mg/kg. The reduction in 3-MCPD ester formation could be due to the removal of related precursors prior to the deodorisation step. The phosphorus content of bleached palm oil showed a significant correlation with 3-MCPD ester formation. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. A 4-week study of four 3-monochloropropane-1,2-diol diesters on lipid metabolism in C57BL/6J mice.

    Science.gov (United States)

    Lu, Jing; Wang, Zhenning; Ren, Mengrou; Feng, Guangxin; Ye, Beining; Wang, Yi; Fang, Baochen; Deng, Xuming; Guan, Shuang

    2015-09-01

    3-Monochloropropane-1,2-diol (3-MCPD) esters have been detected in many foods, which have become a new safety issue worldwide. In the study, we investigated the effect of four 3-MCPD diesters (palmitate diester: CDP; stearate diester: CDS; oleate diester: CDO; linoleate diester: CDL) on lipid metabolism in C57BL/6J mice. The results showed that CDP, CDS, CDO and CDL significantly increased the serum TC, LDL-C levels and liver TG, TC levels at dose of 16.5μmol/kg/day. These results indicated that 3-MCPD diesters could potentially cause hyperlipidemia in C57BL/6J mice. Moreover, oil red O staining confirmed fat accumulation in liver induced by 3-MCPD diesters. Our work will provide more information for safety evaluation of 3-MCPD diesters. However, whether free 3-MCPD or free fatty acids or combined action compensates for the hyperlipidemia effects should be elucidated in the future. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Effects of 3-monochloropropane-1,2-diol (3-MCPD) and its metabolites on DNA damage and repair under in vitro conditions.

    Science.gov (United States)

    Ozcagli, Eren; Alpertunga, Buket; Fenga, Concettina; Berktas, Mehmet; Tsitsimpikou, Christina; Wilks, Martin F; Tsatsakis, Αristidis M

    2016-03-01

    3-monochloropropane-1,2-diol (3-MCPD) is a food contaminant that occurs during industrial production processes and can be found mainly in fat and salt containing products. 3-MCPD has exhibited mutagenic activity in vitro but not in vivo, however, a genotoxic mechanism for the occurrence of kidney tumors has not so far been excluded. The main pathway of mammalian 3-MCPD metabolism is via the formation of β--chlorolactatic acid and formation of glycidol has been demonstrated in bacterial metabolism. The aim of this study was to investigate genotoxic and oxidative DNA damaging effects of 3-MCPD and its metabolites, and to provide a better understanding of their roles in DNA repair processes. DNA damage was assessed by alkaline comet assay in target rat kidney epithelial cell lines (NRK-52E) and human embryonic kidney cells (HEK-293). Purine and pyrimidine base damage, H2O2 sensitivity and DNA repair capacity were assessed via modified comet assay. The results revealed in vitro evidence for increased genotoxicity and H2O2 sensitivity. No association was found between oxidative DNA damage and DNA repair capacity with the exception of glycidol treatment at 20 μg/mL. These findings provide further insights into the mechanisms underlying the in vitro genotoxic potential of 3-MCPD and metabolites. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. IN0523 (Urs-12-ene-3α,24β-diol) a plant based derivative of boswellic acid protect Cisplatin induced urogenital toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Amarinder [Academy of Scientific & Innovative Research (AcSIR), New Delhi (India); PK-PD-Toxicology and Formulation Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu 180001, J& K (India); Arvinda, S [Deptt. of Pathology, Govt. Medical College, Jammu 180001, J& K (India); Singh, Surjeet [PK-PD-Toxicology and Formulation Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu 180001, J& K (India); Suri, Jyotsna [Deptt. of Pathology, Govt. Medical College, Jammu 180001, J& K (India); Koul, Surinder [Bio-Organic Chemistry Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu 180001, J& K (India); Mondhe, Dilip M. [Cancer Pharmacology Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu 180001, J& K (India); Singh, Gurdarshan, E-mail: singh_gd@iiim.ac.in [PK-PD-Toxicology and Formulation Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu 180001, J& K (India); Vishwakarma, Ram [Bio-Organic Chemistry Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu 180001, J& K (India)

    2017-03-01

    The limiting factor for the use of Cisplatin in the treatment of different type of cancers is its toxicity and more specifically urogenital toxicity. Oxidative stress is a well-known phenomenon associated with Cisplatin toxicity. However, in Cisplatin treated group, abnormal animal behavior, decreased body weight, cellular and sub-cellular changes in the kidney and sperm abnormality were observed. Our investigation revealed that Cisplatin when administered in combination with a natural product derivative (Urs-12-ene-3α,24β-diol, labeled as IN0523) resulted in significant restoration of body weight and protection against the pathological alteration caused by Cisplatin to kidney and testis. Sperm count and motility were significantly restored near to normal. Cisplatin caused depletion of defense system i.e. glutathione peroxidase, catalase and superoxide dismutase, which were restored close to normal by treatment of IN0523. Reduction in excessive lipid peroxidation induced by Cisplatin was also found by treatment with IN0523. The result suggests that IN0523 is a potential candidate for ameliorating Cisplatin induced toxicity in the kidney and testes at a dose of 100 mg/kg p.o. via inhibiting the oxidative stress/redox status imbalance and may be improving the efflux mechanism. - Highlights: • Synthesis of a novel boswellic acid derivative (IN0523) • Counter oxidative stress induced due to Cisplatin • Protect against urogenital toxicity induced by Cisplatin.

  20. IN0523 (Urs-12-ene-3α,24β-diol) a plant based derivative of boswellic acid protect Cisplatin induced urogenital toxicity.

    Science.gov (United States)

    Singh, Amarinder; Arvinda, S; Singh, Surjeet; Suri, Jyotsna; Koul, Surinder; Mondhe, Dilip M; Singh, Gurdarshan; Vishwakarma, Ram

    2017-03-01

    The limiting factor for the use of Cisplatin in the treatment of different type of cancers is its toxicity and more specifically urogenital toxicity. Oxidative stress is a well-known phenomenon associated with Cisplatin toxicity. However, in Cisplatin treated group, abnormal animal behavior, decreased body weight, cellular and sub-cellular changes in the kidney and sperm abnormality were observed. Our investigation revealed that Cisplatin when administered in combination with a natural product derivative (Urs-12-ene-3α,24β-diol, labeled as IN0523) resulted in significant restoration of body weight and protection against the pathological alteration caused by Cisplatin to kidney and testis. Sperm count and motility were significantly restored near to normal. Cisplatin caused depletion of defense system i.e. glutathione peroxidase, catalase and superoxide dismutase, which were restored close to normal by treatment of IN0523. Reduction in excessive lipid peroxidation induced by Cisplatin was also found by treatment with IN0523. The result suggests that IN0523 is a potential candidate for ameliorating Cisplatin induced toxicity in the kidney and testes at a dose of 100mg/kg p.o. via inhibiting the oxidative stress/redox status imbalance and may be improving the efflux mechanism. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. DNA polymerase eta participates in the mutagenic bypass of adducts induced by benzo[a]pyrene diol epoxide in mammalian cells.

    Directory of Open Access Journals (Sweden)

    Alden C Klarer

    Full Text Available Y-family DNA-polymerases have larger active sites that can accommodate bulky DNA adducts allowing them to bypass these lesions during replication. One member, polymerase eta (pol eta, is specialized for the bypass of UV-induced thymidine-thymidine dimers, correctly inserting two adenines. Loss of pol eta function is the molecular basis for xeroderma pigmentosum (XP variant where the accumulation of mutations results in a dramatic increase in UV-induced skin cancers. Less is known about the role of pol eta in the bypass of other DNA adducts. A commonly encountered DNA adduct is that caused by benzo[a]pyrene diol epoxide (BPDE, the ultimate carcinogenic metabolite of the environmental chemical benzo[a]pyrene. Here, treatment of pol eta-deficient fibroblasts from humans and mice with BPDE resulted in a significant decrease in Hprt gene mutations. These studies in mammalian cells support a number of in vitro reports that purified pol eta has error-prone activity on plasmids with site-directed BPDE adducts. Sequencing the Hprt gene from this work shows that the majority of mutations are G>T transversions. These data suggest that pol eta has error-prone activity when bypassing BPDE-adducts. Understanding the basis of environmental carcinogen-derived mutations may enable prevention strategies to reduce such mutations with the intent to reduce the number of environmentally relevant cancers.

  2. Enhanced binding capacity of boronate affinity adsorbent via surface modification of silica by combination of atom transfer radical polymerization and chain-end functionalization for high-efficiency enrichment of cis-diol molecules

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Wei; He, Maofang; Wang, Chaozhan; Wei, Yinmao, E-mail: ymwei@nwu.edu.cn

    2015-07-30

    Boronate affinity materials have been widely used for specific separation and preconcentration of cis-diol molecules, but most do not have sufficient capacity due to limited binding sites on the material surface. In this work, we prepared a phenylboronic acid-functionalized adsorbent with a high binding capacity via the combination of surface-initiated atom transfer radical polymerization (SI-ATRP) and chain-end functionalization. With this method, the terminal chlorides of the polymer chains were used fully, and the proposed adsorbent contains dense boronic acid polymers chain with boronic acid on the chain end. Consequently, the proposed adsorbent possesses excellent selectivity and a high binding capacity of 513.6 μmol g{sup −1} for catechol and 736.8 μmol g{sup −1} for fructose, which are much higher than those of other reported adsorbents. The dispersed solid-phase extraction (dSPE) based on the prepared adsorbent was used for extraction of three cis-diol drugs (i.e., epinephrine, isoprenaline and caffeic acid isopropyl ester) from plasma; the eluates were analyzed by HPLC-UV. The reduced amount of adsorbent (i.e., 2.0 mg) could still eliminate interferences efficiently and yielded a recovery range of 85.6–101.1% with relative standard deviations ranging from 2.5 to 9.7% (n = 5). The results indicated that the proposed strategy could serve as a promising alternative to increase the density of surface functional groups on the adsorbent; thus, the prepared adsorbent has the potential to effectively enrich cis-diol substances in real samples. - Highlights: • Boronate adsorbent is prepared via ATRP and chain-end functionalization. • The adsorbent has quite high binding capacity for cis-diols. • Binding capacity is easily manipulated by ATRP condition. • Chain-end functionalization can improve binding capacity significantly. • Reduced adsorbent is consumed in dispersed solid-phase extraction of cis-diols.

  3. Vasodilator effects and putative guanylyl cyclase stimulation by 2-nitro-1-phenylethanone and 2-nitro-2-phenyl-propane-1,3-diol on rat aorta.

    Science.gov (United States)

    Vasconcelos, Thiago Brasileiro de; Ribeiro-Filho, Helder Veras; Lahlou, Saad; Pereira, José Geraldo de Carvalho; Oliveira, Paulo Sérgio Lopes de; Magalhães, Pedro Jorge Caldas

    2018-07-05

    Compounds containing a nitro group may reveal vasodilator properties. Several nitro compounds have a NO 2 group in a short aliphatic chain connected to an aromatic group. In this study, we evaluated in rat aorta the effects of two nitro compounds, with emphasis on a putative recruitment of the soluble guanylate cyclase (sGC) pathway to induce vasodilation. Isolated aortic rings were obtained from male Wistar rats to compare the effects induced by 2-nitro-1-phenylethanone (NPeth) or 2-nitro-2-phenyl-propane-1,3-diol (NPprop). In aortic preparations contracted with phenylephrine or KCl, NPeth and NPprop induced vasorelaxant effects that did not depend on the integrity of vascular endothelium. NPeth had a lesser vasorelaxant efficacy than NPprop and only the NPprop effects were inhibited by pretreatment with the sGC inhibitors, 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ) or methylene blue. In an ODQ-preventable manner, NPprop inhibited the contractile component of the phenylephrine-induced response mediated by intracellular Ca 2+ release or by extracellular Ca 2+ recruitment through receptor- or voltage-operated Ca 2+ channels. In contrast, NPprop was inert against the transient contraction induced by caffeine in Ca 2+ -free medium. In an ODQ-dependent manner, NPprop inhibited the contraction induced by the protein kinase C activator phorbol 12,13-dibutyrate or by the tyrosine phosphatase inhibitor sodium orthovanadate. In silico docking analysis of a sGC homologous protein revealed preferential site for NPprop. In conclusion, the nitro compounds NPeth and NPprop induced vasorelaxation in rat aortic rings. Aliphatic chain substituents selectively interfered in the ability of these compounds to induce vasorelaxant effects, and only NPprop relaxed aortic rings via a sGC pathway. Copyright © 2018 Elsevier B.V. All rights reserved.

  4. 4-(E)-{(p-tolylimino)-methylbenzene-1,2-diol}, 1 a novel resveratrol analog, differentially regulates estrogen receptors α and β in breast cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Ronghe, Amruta; Chatterjee, Anwesha [Division of Pharmacology and Toxicology, School of Pharmacy, University of Missouri-Kansas City, Kansas City, MO 64108 (United States); Singh, Bhupendra [Department of Genetics, School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294 (United States); Dandawate, Prasad [ISTRA, Department of Chemistry, Abeda Inamdar Senior College, University of Pune (India); Abdalla, Fatma; Bhat, Nimee K. [Division of Pharmacology and Toxicology, School of Pharmacy, University of Missouri-Kansas City, Kansas City, MO 64108 (United States); Padhye, Subhash [ISTRA, Department of Chemistry, Abeda Inamdar Senior College, University of Pune (India); Bhat, Hari K., E-mail: bhath@umkc.edu [Division of Pharmacology and Toxicology, School of Pharmacy, University of Missouri-Kansas City, Kansas City, MO 64108 (United States)

    2016-06-15

    Breast cancer is a public health concern worldwide. Prolonged exposure to estrogens has been implicated in the development of breast neoplasms. Epidemiologic and experimental evidence suggest a chemopreventive role of phytoestrogens in breast cancers. Resveratrol, a naturally occurring phytoestrogen, has been shown to have potent anti-cancer properties. However, poor efficacy and bioavailability have prevented the use of resveratrol in clinics. In order to address these problems, we have synthesized a combinatorial library of azaresveratrol analogs and tested them for their ability to inhibit the proliferation of breast cancer cells. We have recently shown that 4-(E)-{(p-tolylimino)-methylbenzene-1,2-diol} (TIMBD), has better anti-cancer properties than resveratrol and any other resveratrol analog we have synthesized so far. The objective of this study was to investigate the regulation of estrogen receptors (ERs) α and β by TIMBD in breast cancer cell lines. We demonstrate that TIMBD significantly induces the mRNA and protein expression levels of ERβ and inhibits that of ERα. TIMBD inhibits mRNA and protein expression levels of oncogene c-Myc, and cell cycle protein cyclin D1, which are important regulators of cellular proliferation. TIMBD significantly induces protein expression levels of tumor suppressor genes p53 and p21 in MCF-7 cells. TIMBD inhibits c-Myc in an ERβ-dependent fashion in MCF-10 A and ERβ1-transfected MDA-MB-231 cells, suggesting regulation of ERs as an important upstream mechanism of this analog. ERβ plays a partial role in inhibition of proliferation by TIMBD while ERα overexpression does not significantly affect TIMBD's inhibition. - Highlights: • Resveratrol analog TIMBD inhibits growth of breast cancer cells. • TIMBD induces protein expression levels of ERβ and inhibits that of ERα. • TIMBD inhibits c-Myc and cyclin D1, and induces p53 and p21. • TIMBD suppresses c-Myc in an ER-dependent fashion.

  5. 4-(E)-{(p-tolylimino)-methylbenzene-1,2-diol}, 1 a novel resveratrol analog, differentially regulates estrogen receptors α and β in breast cancer cells

    International Nuclear Information System (INIS)

    Ronghe, Amruta; Chatterjee, Anwesha; Singh, Bhupendra; Dandawate, Prasad; Abdalla, Fatma; Bhat, Nimee K.; Padhye, Subhash; Bhat, Hari K.

    2016-01-01

    Breast cancer is a public health concern worldwide. Prolonged exposure to estrogens has been implicated in the development of breast neoplasms. Epidemiologic and experimental evidence suggest a chemopreventive role of phytoestrogens in breast cancers. Resveratrol, a naturally occurring phytoestrogen, has been shown to have potent anti-cancer properties. However, poor efficacy and bioavailability have prevented the use of resveratrol in clinics. In order to address these problems, we have synthesized a combinatorial library of azaresveratrol analogs and tested them for their ability to inhibit the proliferation of breast cancer cells. We have recently shown that 4-(E)-{(p-tolylimino)-methylbenzene-1,2-diol} (TIMBD), has better anti-cancer properties than resveratrol and any other resveratrol analog we have synthesized so far. The objective of this study was to investigate the regulation of estrogen receptors (ERs) α and β by TIMBD in breast cancer cell lines. We demonstrate that TIMBD significantly induces the mRNA and protein expression levels of ERβ and inhibits that of ERα. TIMBD inhibits mRNA and protein expression levels of oncogene c-Myc, and cell cycle protein cyclin D1, which are important regulators of cellular proliferation. TIMBD significantly induces protein expression levels of tumor suppressor genes p53 and p21 in MCF-7 cells. TIMBD inhibits c-Myc in an ERβ-dependent fashion in MCF-10 A and ERβ1-transfected MDA-MB-231 cells, suggesting regulation of ERs as an important upstream mechanism of this analog. ERβ plays a partial role in inhibition of proliferation by TIMBD while ERα overexpression does not significantly affect TIMBD's inhibition. - Highlights: • Resveratrol analog TIMBD inhibits growth of breast cancer cells. • TIMBD induces protein expression levels of ERβ and inhibits that of ERα. • TIMBD inhibits c-Myc and cyclin D1, and induces p53 and p21. • TIMBD suppresses c-Myc in an ER-dependent fashion.

  6. A 13-week repeated dose study of three 3-monochloropropane-1,2-diol fatty acid esters in F344 rats.

    Science.gov (United States)

    Onami, Saeko; Cho, Young-Man; Toyoda, Takeshi; Mizuta, Yasuko; Yoshida, Midori; Nishikawa, Akiyoshi; Ogawa, Kumiko

    2014-04-01

    3-monochloropropane-1,2-diol (3-MCPD), a rat renal and testicular carcinogen, has been reported to occur in various foods and food ingredients as free or esterified forms. Since reports about toxicity of 3-MCPD esters are limited, we conducted a 13-week rat subchronic toxicity study of 3-MCPD esters (palmitate diester: CDP, palmitate monoester: CMP, oleate diester: CDO). We administered a carcinogenic dose (3.6 × 10(-4) mol/kg B.W./day) of 3-MCPD or these esters at equimolar concentrations and two 1/4 lower doses by gavage with olive oil as a vehicle five times a week for 13 weeks to F344 male and female rats. As a result, five out of ten 3-MCPD-treated females died from acute renal tubular necrosis, but none of the ester-treated rats. Decreased HGB was observed in all high-dose 3-MCPD fatty acid ester-treated rats, except CDO-treated males. The absolute and relative kidney weights were significantly increased in the ester-treated rats at medium and high doses. Relative liver weights were significantly increased in the esters-treated rat at high dose, except for CMP females. Significant increase in apoptotic epithelial cells in the initial segment of the epididymis of high-dose ester-treated males was also observed. The results suggested that although acute renal toxicity was lower than 3-MCPD, these three 3-MCPD fatty acid esters have the potential to exert subchronic toxicity to the rat kidneys and epididymis, to a similar degree as 3-MCPD under the present conditions. NOAELs (no-observed-adverse-effect levels) of CDP, CMP and CDO were suggested to be 14, 8 and 15 mg/kg B.W./day, respectively.

  7. Occurrence of bound 3-monochloropropan-1,2-diol content in commonly consumed foods in Hong Kong analysed by enzymatic hydrolysis and GC-MS detection.

    Science.gov (United States)

    Chung, Stephen W C; Chan, Benny T P; Chung, H Y; Xiao, Ying; Ho, Y Y

    2013-01-01

    The aim of this study was to determine the level of bound 3-monochloropropan-1,2-diol in foodstuffs commonly consumed in Hong Kong, China, by an enzymatic hydrolysis indirect method which proved to be free from interferences. A total of 290 samples were picked up randomly from the local market and analysed. About 73% of these samples were found to contain detectable amounts of bound 3-MCPD. Amongst the 73 food items, bound 3-MCPD was not detected in 13 food items, including extra virgin olive oil, beef ball/salami, beef flank, ham/Chinese ham, nuts, seeds, soy sauce, oyster sauce, butter, yoghurt, cream, cheese and milk. For those found to contain detectable bound 3-MCPD, the content ranged up to 2500 µg kg(-1). The highest mean bound 3-MCPD content among the 14 food groups was in biscuits (440 [50-860] µg kg(-1)), followed by fats and oils (390 [n.d.-2500] µg kg(-1)), snacks (270 [9-1000] µg kg(-1)), and Chinese pastry (270 [n.d.-1200] µg kg(-1)). Among the samples, the highest bound 3-MCPD content was in a grape seed oil (2500 µg kg(-1)), followed by a walnut flaky pastry (1200 µg kg(-1)) and a grilled corn (1000 µg kg(-1)). Basically, the results of this study agreed well with other published results in peer-reviewed journals, except for cheese, cream, ham, nuts and seeds.

  8. Effect of the Topical Repellent para-Menthane-3,8-diol on Blood Feeding Behavior and Fecundity of the Dengue Virus Vector Aedes aegypti

    Directory of Open Access Journals (Sweden)

    Jugyeong Lee

    2018-06-01

    Full Text Available Dengue fever is an acute disease caused by the dengue virus and transmitted primarily by the mosquito Aedes aegypti. The current strategy for dengue prevention is vector control including the use of topical repellents to reduce mosquito biting. Although N,N-diethyl-m-methylbenzamide (DEET is the most common active ingredient in topical repellent products, para-menthane-3,8-diol (PMD is also used commercially. Studies have indicated PMD reduced biting by 90–95% for up to 6–8 h, similar to the efficacy of DEET, depending on the testing environment. The purpose of this study was to evaluate the behavioral effects of PMD on Ae. aegypti blood feeding and fecundity to explore the potential impact of PMD on downstream mosquito life-history traits. Two experiments were performed. In both experiments, cohorts of female Ae. aegypti (Belize strain were exposed to 20% PMD or ethanol for 10 min in a closed system and introduced to an artificial membrane feeding system. Following a 30min feed time, mosquitoes of Experiment 1 were killed and weighed as a proxy measure of blood meal, whereas mosquitoes of Experiment 2 were monitored for oviposition, a measure of fecundity. Results showed a statistically significant reduction (p < 0.001 in the percentage of Ae. aegypti that blood-fed when exposed to PMD (38% compared to those non-exposed (49%. No significant difference in fecundity between test populations was indicated. These findings suggest that exposure of Ae. aegypti to 20% PMD may influence the probability of subsequent blood feeding but of those mosquitoes that do blood feed, egg-lay density is not affected. Further studies are warranted to investigate the full range of effects of PMD exposure on other Ae. aegypti life-history traits such as mating, to continue characterizing the potential effects of PMD to impact overall vector population dynamics.

  9. Solvatochromic effect studies on the absorption spectra of 4-((2-ethylphenyl)diazenyl)benzene-1,3-diol and 2-((2-ethylphenyl)diazenyl)benzene-1,3,5-triol molecules

    Energy Technology Data Exchange (ETDEWEB)

    Guelseven, Yadigar; Tasal, Erol; Sidir, Isa [Department of Physics, Faculty of Arts and Sciences, Eskisehir Osmangazi University, Eskisehir 26480 (Turkey); Guengoer, Tayyar [Department of Physics, Faculty of Arts and Sciences, Akdeniz University, Antalya (Turkey); Berber, Halil [Department of Chemistry, Faculty of Sciences, Anadolu University, Eskisehir (Turkey); Oegretir, Cemil [Department of Chemistry, Faculty of Arts and Sciences, Eskisehir Osmangazi University, Eskisehir (Turkey)

    2009-06-15

    The electronic absorption spectra of 4-((2-ethylphenyl)diazenyl)benzene-1,3-diol and 2-((2-ethylphenyl)diazenyl)benzene-1,3,5-triol molecules in the nine different solvent variable electronic characters have been recorded. The solvent dependent maximum absorption band ({pi}-{pi}* transitions) shifts, {nu}{sub max}, were analyzed using a wide range of parameters such as refractive index, dielectric constant and Kamlet-Taft parameters [hydrogen bond donating ability ({alpha}) and hydrogen bond accepting ability ({beta})]. The electronic transitions are assigned and the solvent-induced spectral shifts have been analyzed in relation to the different solute-solvent interaction mechanism using computational chemistry. The intermolecular interaction types in the azobenzene derivatives solutions have been established on the basis of a multiple linear regression analysis. The fitting coefficients obtained from this analysis allowed us to estimate the contribution of each type of interactions to the total spectral shifts in the studied solutions. (author)

  10. Synthesis, structural, spectroscopic, anti-cancer and molecular docking studies on novel 2-[(Anthracene-9-ylmethylene)amino]-2-methylpropane-1,3-diol using XRD, FTIR, NMR, UV-Vis spectra and DFT

    Science.gov (United States)

    Pavitha, P.; Prashanth, J.; Ramu, G.; Ramesh, G.; Mamatha, K.; Venkatram Reddy, Byru

    2017-11-01

    The novel titled compound 2-[(Anthracene-9-ylmethylene)amino]-2-methylpropane-1,3-diol (AMD) has been synthesized by slow evaporation technique from mixed solvent system of methanol with anthracene-9-carbaldehyde and 2-amino-2-methylpropane-1,3-diol. The synthesized molecule AMD was characterized experimentally by single crystal XRD, FTIR, NMR and UV-Vis spectra and density functional theory (DFT) computations. The structure of the crystal has been determined as orthorhombic system with space group P 21 21 21 and the cell parameters are obtained using XRD data. The optimized ground state geometry of the molecule is determined by evaluating torsional potentials as a function of angle of free rotation around Csbnd C bonds of functional groups by DFT method employing B3LYP functional with 6-311++G(d,p) basis set. All the fundamental vibrations of the molecule are assigned unambiguously using potential energy distribution (PED) obtained in the DFT computations. The rms error between the observed and scaled frequencies is 6.20 cm-1. The values of dipole moment, polarizability and hyperpolarizability are evaluated to study the NLO behavior of the molecule. The HOMO-LUMO energies and thermodynamic parameters are also determined. The molecular electrostatic surface potential (MESP) is mapped to obtain the charge density distribution. The 1H and 13C NMR chemical shifts of the molecule are calculated by the gauge independent atomic orbital (GIAO) method and compared with experimental results. UV-visible spectrum of the compound is also recorded in the region 200-800 nm to know the type of electronic transitions involved. The anti-cancer activity of AMD is determined against human breast cancer cell line MCF-7 and human prostate cancer cell line PC-3 and correlated the results with study of molecular docking against pharmacological protein IDO-1 receptor.

  11. 3,3′,4,4′,5-Pentachlorobiphenyl (PCB 126) Decreases Hepatic and Systemic Ratios of Epoxide to Diol Metabolites of Unsaturated Fatty Acids in Male Rats

    Science.gov (United States)

    Wu, Xianai; Yang, Jun; Morisseau, Christophe; Robertson, Larry W.; Hammock, Bruce; Lehmler, Hans-Joachim

    2016-01-01

    Disruption of the homeostasis of oxygenated regulatory lipid mediators (oxylipins), potential markers of exposure to aryl hydrocarbon receptor (AhR) agonists, such as 3,3′,4,4′,5-pentachlorobiphenyl (PCB 126), is associated with a range of diseases, including nonalcoholic fatty liver disease and nonalcoholic steatohepatitis. Here we test the hypothesis that PCB 126 exposure alters the levels of oxylipins in rats. Male Sprague-Dawley rats (5-weeks old) were treated over a 3-month period every 2 weeks with intraperitoneal injections of PCB 126 in corn oil (cumulative doses of 0, 19.8, 97.8, and 390 µg/kg b.w.; 6 injections total). PCB 126 treatment caused a reduction in growth rates at the highest dose investigated, a dose-dependent decrease in thymus weights, and a dose-dependent increase in liver weights. Liver PCB 126 levels increased in a dose-dependent manner, while levels in plasma were below or close to the detection limit. The ratios of several epoxides to diol metabolites formed via the cytochrome P450 (P450) monooxygenase/soluble epoxide hydrolase (sEH) pathway from polyunsaturated fatty acids displayed a dose-dependent decrease in the liver and plasma, whereas levels of oxylipins formed by other metabolic pathways were generally not altered by PCB 126 treatment. The effects of PCB 126 on epoxide-to-diol ratios were associated with an increased CYP1A activity in liver microsomes and an increased sEH activity in liver cytosol and peroxisomes. These results suggest that oxylipins are potential biomarkers of exposure to PCB 126 and that the P450/sEH pathway is a therapeutic target for PCB 126-mediated hepatotoxicity that warrants further attention. PMID:27208083

  12. Synthesis and crystal structures of two α-bromoamides, (2'R,1S,2S)-N(2-bromopropanoyl)-2-amino-1-phenylpropane-1,3-diol and (2'S,5S,6S)-N(2-bromopropanoyl)-5-amino-6-phenyl-2-oxo-1,3,2-dioxathiane

    International Nuclear Information System (INIS)

    English, R.B.; Liddell, R.J.; Whiteley, C.G.

    1987-01-01

    One pair of diastereomeric bromoamides, (2'R,1S,2S)- and (2'S,1S,2S)-N(2-bromopropanoyl)-2-amino-1-phenylpropane-1,3-diol have been synthesized from ethyl 2-bromopropionate and an optically active amino-diol. The crystal structures of both were determined from single-crystal X-ray analyses. Both compounds are orthorhombic with space group P2 1 2 1 2 1 with Z = 4 in a unit cell of dimensions a 22,124(5),b 12,812(5), and c 4,886(5)A and a 15,510(5), b 9,707(5), and c 9,457(5)A. The proton chemical shifts of the groups attached to the asymmetric centre C(2'), and consequently, the identification of the configuration of the molecules, were resolved with the help of high-resolution nuclear magnetic resonance

  13. The role of hRev7, the accessory subunit of hPolζ, in translesion synthesis past DNA damage induced by benzo[a]pyrene diol epoxide (BPDE

    Directory of Open Access Journals (Sweden)

    Maher Veronica M

    2010-12-01

    Full Text Available Abstract Background DNA polymerase zeta (Polζ is a specialized DNA polymerase that, unlike classical replicative polymerases, is capable of replicating past DNA lesions, i.e. of performing translesion synthesis (TLS. The catalytic subunit of hPolζ, hRev3, has been shown to play a critical role in DNA damage-induced mutagenesis in human cells, but less is known about the role of hRev7, the accessory subunit of hPolζ, in such mutagenesis. To address this question, we recently generated human fibroblasts with very significantly reduced levels of hRev7 protein and demonstrated that hRev7 is required to protect cells from ultraviolet(254 nm (UV radiation-induced cytotoxicity and mutagenesis (McNally et al., DNA Repair 7 (2008 597-604. The goal of the present study was to determine whether hRev7 is similarly involved in the tolerance of DNA damage induced by benzo[a]pyrene diol epoxide (BPDE, the reactive form of the widespread environmental carcinogen benzo[a]pyrene. Methods To determine whether hRev7 also plays a role in protecting human cells from the cytotoxicity and mutagenesis induced by benzo[a]pyrene diol epoxide (BPDE, cell strains with reduced hRev7 were compared to their parental strain and a vector control strain for the effect of BPDE on cell survival, induction of mutations, and the ability to progress through the cell cycle. Results The results show that cell strains with reduced hRev7 are more sensitive to the cytotoxic effect of BPDE than the control strains, and progress through S-phase at a slower rate than the control cells following BPDE treatment, indicating that hRev7, and likely hPolζ, is required for efficient bypass of BPDE-induced DNA lesions. However, neither the frequency nor kinds of mutations induced by BPDE in cells with reduced hRev7 differ significantly from those induced in the control strains, suggesting that hPolζ is not essential for inserting nucleotides opposite BPDE-induced DNA damage. Conclusions Taken

  14. Marine Bromophenol Derivative 3,4-Dibromo-5-(2-bromo-3,4-dihydroxy-6-isopropoxymethyl benzylbenzene-1,2-diol Protects Hepatocytes from Lipid-Induced Cell Damage and Insulin Resistance via PTP1B Inhibition

    Directory of Open Access Journals (Sweden)

    Jiao Luo

    2015-07-01

    Full Text Available 3,4-Dibromo-5-(2-bromo-3,4-dihydroxy-6-isopropoxymethyl benzylbenzene-1,2-diol (HPN is a bromophenol derivative from the marine red alga Rhodomela confervoides. We have previously found that HPN exerted an anti-hyperglycemic property in db/db mouse model. In the present study, we found that HPN could protect HepG2 cells against palmitate (PA-induced cell death. Data also showed that HPN inhibited cell death mainly by blocking the cell apoptosis. Further studies demonstrated that HPN (especially at 1.0 μM significantly restored insulin-stimulated tyrosine phosphorylation of IR and IRS1/2, and inhibited the PTP1B expression level in HepG2 cells. Furthermore, the expression of Akt was activated by HPN, and glucose uptake was significantly increased in PA-treated HepG2 cells. Our results suggest that HPN could protect hepatocytes from lipid-induced cell damage and insulin resistance via PTP1B inhibition. Thus, HPN can be considered to have potential for the development of anti-diabetic agent that could protect both hepatic cell mass and function.

  15. Serum Level of Antibodies (IgG, IgM Against Benzo[a]pyrene-7,8-diol-9,10-epoxide-DNA Adducts in Children Dermatologically Exposed to Coal Tar

    Directory of Open Access Journals (Sweden)

    Pavel Borský

    2017-06-01

    Full Text Available Crude coal tar (CCT contains polycyclic aromatic hydrocarbons (PAHs. Benzo[a]pyrene (BaP is metabolized into a highly reactive metabolite benzo[a]pyrene-7,8-diol-9,10-epoxide (BPDE that is able to bind to DNA and creates BPDE-DNA adducts. Adducted DNA becomes immunogenic and induces immune response by production of antibodies against BPDE-DNA adducts (Ab-BPDE-DNA. Circulating Ab-BPDE-DNA was proposed as potential biomarker of genotoxic exposure to BaP (PAHs. Goeckerman therapy (GT of psoriasis uses dermal application of CCT ointment (PAHs. In presented study (children with psoriasis treated by GT; n = 19 the therapy significantly increased the level of Ab-BPDE-DNA (EI = 0.29/0.19–0.34 vs. 0.31/0.25–0.40; median/lower–upper quartile; p < 0.01. The results support the idea of Ab-BPDE-DNA level as a possible tentative indicator of exposure, effects and susceptibility of the organism to the exposure of BaP (PAHs.

  16. Evaluation of the genotoxic potential of 3-monochloropropane-1,2-diol (3-MCPD) and its metabolites, glycidol and beta-chlorolactic acid, using the single cell gel/comet assay.

    Science.gov (United States)

    El Ramy, R; Ould Elhkim, M; Lezmi, S; Poul, J M

    2007-01-01

    3-monochloropropane-1,2-diol (3-MCPD) is a member of a group of chemicals known as chloropropanols. It is found in many foods and food ingredients as a result of food processing. 3-MCPD is regarded as a rat carcinogen known to induce Leydig-cell and mammary gland tumours in males and kidney tumours in both genders. The aim of our study was to clarify the possible involvement of genotoxic mechanisms in 3-MCPD induced carcinogenicity at the target organ level. For that purpose, we evaluated DNA damages in selected target (kidneys and testes) and non-target (blood leukocytes, liver and bone marrow) male rat organs by the in vivo alkaline single cell gel electrophoresis (comet) assay, 3 and 24 h after 3-MCPD oral administration to Sprague-Dawley and Fisher 344 adult rats. 3-MCPD may be metabolised to a genotoxic intermediate, glycidol, whereas the predominant urinary metabolite in rats following 3-MCPD administration is beta-chlorolactic acid. Therefore, we also studied the DNA damaging effects of 3-MCPD and its metabolites, glycidol and beta-chlorolactic acid, in the in vitro comet assay on CHO cells. Our results show the absence of genotoxic potential of 3-MCPD in vivo in the target as well as in the non-target organs. Glycidol, the epoxide metabolite, induced DNA damages in CHO cells. beta-Chlorolactic acid, the main metabolite of 3-MCPD in rats, was shown to be devoid of DNA-damaging effects in vitro in mammalian cells.

  17. Effects of DK-002, a synthesized (6aS,cis)-9,10-Dimethoxy-7,11b-dihydro-indeno[2,1-c]chromene-3,6a-diol, on platelet activity.

    Science.gov (United States)

    Lee, Ki-Seon; Khil, Lee-Yong; Chae, Sang-Ho; Kim, Deukjoon; Lee, Byung-Hoon; Hwang, Gwi-Seo; Moon, Chang-Hyun; Chang, Tong-Shin; Moon, Chang-Kiu

    2006-02-02

    In the present study, the mechanism of antiplatelet activity of DK-002, a synthesized (6aS,cis)-9,10-Dimethoxy-7,11b-dihydro-indeno[2,1-c]chromene-3,6a-diol, was investigated. DK-002 inhibited the thrombin, collagen, and ADP-induced rat platelet aggregation in a concentration-dependent manner, with IC50 values of 120, 27, and 47 microM, respectively. DK-002 also inhibited thrombin-induced dense granule secretion, thromboxane A2 synthesis, and [Ca2+]i elevation in platelets. DK-002 did not show any significant effect on ADP-induced inhibition of cyclic AMP elevation by prostaglandin E1, but DK-002 was confirmed to inhibit ADP-induced [Ca2+]i elevation and shape change. DK-002 inhibited 4-bromo-A23187-induced [Ca2+]i elevation in the presence of creatine phosphate/creatine phosphokinase (CP/CPK, a ADP scavenging system) and indomethacin (a specific inhibitor of cyclooxygenase). DK-002 also inhibited Ca2+ mobilization in thrombin- or 4-bromo-A23187-stimulated platelets through its inhibitory effects on both Ca2+ release from intracellular stores and Ca2+ influx, in the presence of CP/CPK and indomethacin. Taken together, the present study shows that DK-002 has inhibitory effects on stimulation of platelets, and suggests that its antiplatelet activity might be related to the inhibitory mechanism on Ca2+ mobilization in stimulated platelets.

  18. Dispersive microextraction based on water-coated Fe₃O₄ followed by gas chromatography-mass spectrometry for determination of 3-monochloropropane-1,2-diol in edible oils.

    Science.gov (United States)

    Zhao, Qin; Wei, Fang; Xiao, Neng; Yu, Qiong-Wei; Yuan, Bi-Feng; Feng, Yu-Qi

    2012-06-01

    In the present work, we developed a novel dispersive microextraction technique by combining the advantages of liquid-phase microextraction (LPME) and magnetic solid-phase extraction (MSPE). In this method, trace amount of water directly absorbed on bare Fe₃O₄ to form water-coated Fe₃O₄ (W-Fe₃O₄) and rapid extraction can be achieved while W-Fe₃O₄ dispersed in the sample solution. The analyte adsorbed W-Fe₃O₄ can be easily collected and isolated from sample solution by application of a magnet. It was worth noting that in the proposed method water was used as extractant and Fe₃O₄ served as the supporter and retriever of water. The performance of the method was evaluated by extraction of 3-monochloropropane-1,2-diol (3-MCPD) from edible oils. The extracted 3-MCPD was then derived by a silylanization reagent (1-trimethylsilylimidazole) before gas chromatography-mass spectrometry (GC-MS) analysis. Several parameters that affected the extraction and derivatization efficiency were investigated. Our results showed that the limit of detection for 3-MCPD was 1.1 ng/g. The recoveries in spiked oil samples were in the range of 70.0-104.9% with the RSDs less than 5.6% (intra-day) and 6.4% (inter-day). Taken together, the simple, rapid and cost-effective method developed in current study, offers a potential application for the extraction and preconcentration of hydrophilic analytes from complex fatty samples. Copyright © 2012 Elsevier B.V. All rights reserved.

  19. Vasorelaxant and Hypotensive Effects of an Ethanolic Extract of Eulophia macrobulbon and Its Main Compound 1-(4′-Hydroxybenzyl-4,8-Dimethoxyphenanthrene-2,7-Diol

    Directory of Open Access Journals (Sweden)

    Sutthinee Wisutthathum

    2018-05-01

    Full Text Available Background: Ethnopharmacological studies demonstrated the potential for Eulophia species to treat inflammation, cancer, and cardio-metabolic diseases. The aim of the study was to investigate the vasorelaxant effect of ethanolic Eulophia macrobulbon (EM extract and its main phenanthrene on rat isolated mesenteric artery and to investigate the hypotensive effect of EM.Methods: The vasorelaxant effects of EM extract or phenanthrene and the underlying mechanisms were evaluated on second-order mesenteric arteries from Sprague Dawley rats. In addition, the acute hypotensive effect was evaluated in anesthetized rats infused with cumulative concentrations of the EM extract.Results: Both EM extract (10-4–1 mg/ml and phenanthrene (10-7–10-4 M relaxed endothelium-intact arteries, an effect that was partly reduced by endothelium removal (p < 0.001. A significant decrease in the relaxant effect of the extract and the phenanthrene was observed with L-NAME and apamin/charybdotoxin in endothelium-intact vessels, and with iberiotoxin in denuded vessels. SNP (sodium nitroprusside-induced relaxation was significantly enhanced by EM extract and phenanthrene. By contrast, ODQ (1H-[1,2,4]oxadiazolo[4,3-a]quinoxaline-1-one, 4-aminopyridine and glibenclamide (endothelium-denuded vessels and indomethacin (endothelium-intact vessels had no effect. In calcium-free solution, both the EM extract and phenanthrene inhibited extracellular Ca2+-induced contraction in high KCl and phenylephrine (PE pre-contracted rings. They also inhibited the intracellular Ca2+ release sensitive to PE. The acute infusion of EM extract (20 and 70 mg/kg induced an immediate and transient dose-dependent hypotensive effect.Conclusion: The ethanolic extract of EM tubers and its main active compound, 1-(4′-hydroxybenzyl-4,8-dimethoxyphenanthrene-2,7-diol (phenanthrene induced vasorelaxant effects on rat resistance vessels, through pleiotropic effects including endothelium-dependent effects (NOS

  20. Absence of in vivo genotoxicity of 3-monochloropropane-1,2-diol and associated fatty acid esters in a 4-week comprehensive toxicity study using F344 gpt delta rats.

    Science.gov (United States)

    Onami, Saeko; Cho, Young-Man; Toyoda, Takeshi; Horibata, Katsuyoshi; Ishii, Yuji; Umemura, Takashi; Honma, Masamitsu; Nohmi, Takehiko; Nishikawa, Akiyoshi; Ogawa, Kumiko

    2014-07-01

    3-Monochloropropane-1,2-diol (3-MCPD) is regarded as a rat renal and testicular carcinogen and has been classified as a possible human carcinogen (group 2B) by International Agency for Research on Cancer. This is potentially of great importance given that esters of this compound have recently found to be generated in many foods and food ingredients as a result of food processing. There have been a few reports about their toxicity, although we have recently found that the toxicity profile of 3-MCPD esters was similar to that of 3-MCPD in a rat 13-week repeated dose study, except for the acute renal toxicity seen in 3-MCPD-treated females. In the present study, to examine in vivo genotoxicity we administered equimolar doses of 3-MCPD or 3-MCPD fatty acid esters (palmitate diester, palmitate monoester and oleate diester) to 6-week-old male F344 gpt delta rats carrying a reporter transgene for 4 weeks by intragastric administration. In vivo micronucleus, Pig-a mutation and gpt assays were performed, as well as investigations of major toxicological parameters including histopathological features. As one result, the relative kidney weights of the 3-MCPD and all three ester groups were significantly increased compared with the vehicle control group. However, the frequency of micronucleated reticulocytes and Pig-a mutant red blood cells did not differ among groups. Moreover, no changes were observed in mutant frequencies of gpt and red/gam (Spi(-)) genes in the kidney and the testis of 3-MCPD and 3-MCPD-fatty-acid-esters-treated rats. In histopathological analyses, no treatment related changes were observed, except for decrease of eosinophilic bodies in the kidneys of all treated groups. These results suggest that 3-MCPD and its fatty acid esters are not in vivo genotoxins, although they may exert renal toxicity. © The Author 2014. Published by Oxford University Press on behalf of the UK Environmental Mutagen Society. All rights reserved. For permissions, please e

  1. epoxy isocapnolactone and 8- hydroxyisocapnolactone-2'3'-diol ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-09-15

    Sep 15, 2009 ... microscope analyses, the compounds were confirmed to have ability in promoting apoptosis. However, ... Some of them have cytostatic properties and the others ..... rescent images of untreated cells, 2',3'-epoxyisocapno-.

  2. Rhenium-Catalyzed Deoxydehydration of Diols and Polyols

    DEFF Research Database (Denmark)

    Dethlefsen, Johannes Rytter; Fristrup, Peter

    2015-01-01

    The substitution of platform chemicals of fossil origin by biomass-derived analogues requires the development of chemicaltransformations capable of reducing the very high oxygen contentof biomass. One such reaction, which has received increasingattention within the past five years, is the heniumc......The substitution of platform chemicals of fossil origin by biomass-derived analogues requires the development of chemicaltransformations capable of reducing the very high oxygen contentof biomass. One such reaction, which has received increasingattention within the past five years...... systems that have been developed withemphasis on the nature of the reductant, the substrate scope,and mechanistic investigations....

  3. The epoxide-diol pathway in the metabolism of vinylbital in rat and man

    NARCIS (Netherlands)

    Vermeulen, N P; Bakker, B H; Eylers, D; Breimer, D D

    1. In urine of rats given vinylbital (5-vinyl-5-(1'-methylbutyl)barbituric acid) i.p., unchanged vinylbital and its devinylated metabolite, 5-(1'-methylbutyl)barbituric acid, were identified. Rats synthetic 1',2'-epoxyvinylbital excreted the same compound as a major metabolite. No unchanged epoxide,

  4. Electrooxidation of activated alpha,omega-diols to cyclic tetramethylene acetals of the corresponding dials

    Czech Academy of Sciences Publication Activity Database

    Hlavatý, Jaromír; Polášek, Miroslav

    2006-01-01

    Roč. 47, č. 44 (2006), s. 7789-7791 ISSN 0040-4039 R&D Projects: GA ČR GA203/03/0825 Institutional research plan: CEZ:AV0Z40400503 Keywords : anodic oxidation * cyclic tetramethylene acetals * 2,7-dioxepyl derivatives Subject RIV: CG - Electrochemistry Impact factor: 2.509, year: 2006

  5. Oxidative C-C bond cleavage of 1,2-diols by silver(II)

    International Nuclear Information System (INIS)

    Kumar, A.

    1981-01-01

    Oxidation of ethylene glycol and related compounds by Ag(II) has been investigated. Complexation of these substrates by Ag(II) precedes their oxidation. Oxidation occurs through electron transfer from an OH group to the Ag(II) within the complex resulting in the formation of alkoxyl-type radicals. The radicals thus formed undergo β-scission to give cleavage products. For ethylene glycol a complexation rate 1.3 x 10 6 M -1 s -1 and oxidation rate approx. 3 x 10 3 s -1 were observed. A general trend for the type of the substrates which would undergo C-C bond scission by Ag(II) is discussed

  6. The waterborne polyurethane dispersions based on polycarbonate diol: effect of ionic content

    Czech Academy of Sciences Publication Activity Database

    Cakić, S. M.; Špírková, Milena; Ristić, I. S.; B-Simendić, J. K.; M-Cincović, M.; Poreba, Rafal

    2013-01-01

    Roč. 138, č. 1 (2013), s. 277-285 ISSN 0254-0584 R&D Projects: GA ČR GAP108/10/0195 Institutional research plan: CEZ:AV0Z40500505 Keywords : coatings * chemical synthesis * thermogravimetric analysis (TGA) Subject RIV: CD - Macromolecular Chemistry Impact factor: 2.129, year: 2013

  7. A model for the calculation of lanthanide induced shifts of bidentate ligands - 1,3-diols

    International Nuclear Information System (INIS)

    Hofer, O.; Griengl, H.; Nowak, P.

    1978-01-01

    The NMR-LIS data of the four diastereomeric 2-(hydroxyphenylmethyl) cyclohexanols 1-4 are used to test two possible computational models for bidentate Eu(dpm)B 3 complexes. A model taking into account the presence of two equivalent coordinaton centers by averaging the corresponding dipolar fields of both centers proved to be superior to the simpler one assuming only one dipolar field with a fictive coordination center at a point equidistant between the two actual coordination sites. (author)

  8. Solvent free oxidation of primary alcohols and diols using thymine iron(III) catalyst.

    Science.gov (United States)

    Al-Hunaiti, Afnan; Niemi, Teemu; Sibaouih, Ahlam; Pihko, Petri; Leskelä, Markku; Repo, Timo

    2010-12-28

    In this study, we developed an efficient and selective iron-based catalyst system for the synthesis of ketones from secondary alcohols and carboxylic acids from primary alcohol. In situ generated iron catalyst of thymine-1-acetate (THA) and FeCl(3) under solvent-free condition exhibits high activity. As an example, 1-octanol and 2-octanol were oxidized to 1-octanoic acid and 2-octanone with 89% and 98% yields respectively.

  9. (E-1,1,4,4-Tetraphenylbut-2-yne-1,4-diol

    Directory of Open Access Journals (Sweden)

    P. L. Nilantha Lakshman

    2010-03-01

    Full Text Available The molecule of the title compound, C28H22O2, is centrosymmetric with the inversion centre located at the mid-point of the C[triple-bond]C bond [1.178 (5 Å]. The hydroxyl groups therefore lie on either side of the molecule. The crystal structure is stabilized by O—H...O hydrogen bonds, leading to the formation of a linear supramolecular chain along the b axis.

  10. 1,3,5-Tri-p-tolylpentane-1,5-diol

    Directory of Open Access Journals (Sweden)

    A. Thiruvalluvar

    2014-02-01

    Full Text Available In the title compound, C26H30O2, the central benzene ring forms dihedral angles of 14.85 (15 and 28.17 (14° with the terminal benzene rings. The dihedral angle between the terminal benzene rings is 32.14 (13°. The crystal packing exhibits two strong intermolecular O—H...O hydrogen bonds, forming directed four-membered co-operative rings. A region of disordered electron density, most probably disordered ethyl acetate solvent molecules, occupying voids of ca 519 Å3 for an electron count of 59, was treated using the SQUEEZE routine in PLATON [Spek (2009. Acta Cryst. D65, 148–155]. Their formula mass and unit-cell characteristics were not taken into account during refinement. The structure was refined as an inversion twin [absolute structure parameter = −0.3 (4].

  11. The investigation of the reactions of some pyrazole-3-carboxylic acids with various diamines and diols

    Directory of Open Access Journals (Sweden)

    Rahmi Kasımoğulları

    2012-06-01

    Full Text Available In this study, some new derivatives were synthesized of 4-benzoyl-1-(3-nitrophenyl-5-phenyl-1H-pyrazole-3-carboxylic acid (1 and 4-(ethoxycarbonyl-1-(3-nitrophenyl-5-phenyl-1H-pyrazole-3-carboxylic acid (2 that they were pyrazole carboxylic acid derivatives. Firstly, 1 and 2 reacted with SOCl2 to transform them into acyl chlorides (3, 4. Then various bis-carboxamide derivatives (5–8 were obtained from the reaction of 3 and 4 with various diamines and also a ;#946;-hydroxy ester (9 derivative was obtained from the reaction of 3 with ethylene glycol. The structures of synthesized compounds were elucidated with using FT-IR, 1H NMR, 13C NMR and elemental analysis methods.

  12. Thermoreversible covalent crosslinking of maleated ethylene/propylene copolymers with diols

    NARCIS (Netherlands)

    Mee, van der M.A.J.; Goossens, J.G.P.; Duin, van M.

    2008-01-01

    Maleated ethylene/propylene copolymer (MAn-g-EPM) was thermoreversibly cross-linked using different routes, i.e. ionic interactions (ionomers), hydrogen bonding and a combination thereof. Microphase separation into polar MAn-rich aggregates occurs for MAn-g-EPM and all cross-linked materials, which

  13. Total synthesis of broussonetine F: the orthoamide Overman rearrangement of an allylic diol.

    Science.gov (United States)

    Hama, Naoto; Aoki, Toshihiro; Miwa, Shohei; Yamazaki, Miki; Sato, Takaaki; Chida, Noritaka

    2011-02-18

    A first total synthesis of broussonetine F from diethyl L-tartrate was achieved. The cornerstone of our synthesis was an orthoamide Overman rearrangement, which provided an allylic amino alcohol with complete diastereoselectivity.

  14. Inert Reassessment Document for 3,6-Diemthyl-4-octyn-3,6-diol

    Science.gov (United States)

    These chemicals are used as surfactants in pesticide formulations applied to growing crops, raw agricultural commodities, and animals with use limitations of not more than 2.5 in formulation and application to soil prior to planting.

  15. DFT Study of the Molybdenum-Catalyzed Deoxydehydration of Vicinal Diols

    DEFF Research Database (Denmark)

    Lupp, Daniel; Christensen, Niels Johan; Dethlefsen, Johannes Rytter

    2015-01-01

    , and extrusion of the alkene. We have compared the proposed pathway with several alternatives, and the results have been corroborated by comparison with the molybdenum- catalyzed sulfoxide reduction recently published by Sanz et al. and with experimental observations for the DODH itself. Improved understanding...

  16. Radical Additions to Fluoroolefins. Photochemical Fluoroalkylation of Alkanols and Alkane Diols with Perfluoro Vinyl Ethers; Photo-Supported O-Alkylation of Butane-1,4-Diol with Hexafluoropropene

    Czech Academy of Sciences Publication Activity Database

    Církva, Vladimír; Polák, R.; Paleta, O.

    1996-01-01

    Roč. 80, č. 2 (1996), s. 135-144 ISSN 0022-1139 Institutional research plan: CEZ:AV0Z4072921 Keywords : radical addition * regioselectivity * perfluoroolefins Subject RIV: CC - Organic Chemistry Impact factor: 0.689, year: 1996

  17. Synthesis of novel lidocaine-releasing poly(diol-co-citrate) elastomers by using deep eutectic solvents.

    Science.gov (United States)

    Serrano, M Concepción; Gutiérrez, María C; Jiménez, Ricardo; Ferrer, M Luisa; del Monte, Francisco

    2012-01-14

    Poly(octanediol-co-citrate) elastomers containing high loading of lidocaine were synthesized at temperatures below 100 °C by means of using deep eutectic mixtures of 1,8-octanediol and lidocaine. The preservation of lidocaine integrity resulted in high-capacity drug-eluting elastomers. This journal is © The Royal Society of Chemistry 2012

  18. Sustainable Pathways to Pyrroles through Iron-Catalyzed N-Heterocyclization from Unsaturated Diols and Primary Amines

    NARCIS (Netherlands)

    Yan, Tao; Barta, Katalin

    2016-01-01

    Pyrroles are prominent scaffolds in pharmaceutically active compounds and play an important role in medicinal chemistry. Therefore, the development of new, atom-economic, and sustainable catalytic strategies to obtain these moieties is highly desired. Direct catalytic pathways that utilize readily

  19. Molybdenum-catalyzed conversion of diols and biomass-derived polyols to alkenes using isopropyl alcohol as reductant and solvent

    DEFF Research Database (Denmark)

    Dethlefsen, Johannes Rytter; Lupp, Daniel; Gorfo, Ayele Teshome

    2015-01-01

    %. The DODH of erythritol yields 39% 2,5-dihydrofuran, while the DODH of the proposed intermediate 1,4-anhydroerythritol yields 75%. The mechanism of the DODH of 1,4-anhydroerythritol was investigated by means of density functional theory (DFT), and the rate-determining step (24.1 kcal/mol) was found...

  20. The influence of montmorillonite and bentonite addition on thermal properties of polyurethanes based on aliphatic polycarbonate diols

    Czech Academy of Sciences Publication Activity Database

    Pavličević, J.; Špírková, Milena; Strachota, Adam; Meszaros Szecsenyi, K.; Lazić, N.; Budinski-Simendic, J.

    2010-01-01

    Roč. 509, 1/2 (2010), s. 73-80 ISSN 0040-6031 R&D Projects: GA ČR GAP108/10/0195 Institutional research plan: CEZ:AV0Z40500505 Keywords : segmented polyurethanes * thermal stability * elastomers Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.908, year: 2010

  1. Bis(1,10-phenanthroline-κ2N,N′(sulfato-Ocopper(II ethane-1,2-diol monosolvate

    Directory of Open Access Journals (Sweden)

    Kai-Long Zhong

    2011-09-01

    Full Text Available In the title compound, [Cu(SO4(C12H8N22]·C2H6O2, the CuII ion is five-coordinated in a distorted square-pyramidal manner by four N atoms from two chelating 1,10-phenanthroline (phen ligands and one O atom from a monodentate sulfate anion. The four N atoms comprise a square and the one O atom the apex of a square pyramid. The two chelating N2C2 groups are oriented at 71.1 (2°. In the crystal, the components are connected by intermolecular O—H...O hydrogen bonding. The presence of pseudosymmetry in the structure suggests the higher symmetry space group C2/c, but attempts to refine the structure in this space group resulted in an unsatisfactory model.

  2. The synthesis of amphipathic prodrugs of 1,2-diol drugs with saccharide conjugates by high regioselective enzymatic protocol.

    Science.gov (United States)

    Quan, Jing; Chen, Zhichun; Han, Chengyou; Lin, Xianfu

    2007-02-15

    A facile, high regioselective enzymatic synthesis approach for the preparation of amphipathic prodrugs with saccharides of mephenesin and chlorphenesin was developed. Firstly, transesterification of two drugs with divinyl dicarboxylates with different carbon chain length was performed under the catalysis of Candida antarctica lipase acrylic resin and Lipozyme in anhydrous acetone at 50 degrees C, respectively. A series of lipophilic derivatives with vinyl groups of mephenesin and chlorphenesin were prepared. The influences of different organic solvents, enzyme sources, reaction time, and the acylation reagents on the synthesis of vinyl esters were investigated. And then, protease-catalyzed high regioselective acylation of D-glucose and D-mannose with vinyl esters of mephenesin and chlorphenesin gave drug-saccharide derivatives in good yields. The studies of lipophilicity and hydrolysis in vitro of prodrugs verified that drug-saccharide derivatives had amphipathic properties, and both lipophilic and amphipathic drug derivatives had obvious controlled release characteristics.

  3. Mechanism of formation of 3-chloropropan-1,2-diol (3-MCPD) esters under conditions of the vegetable oil refining.

    Science.gov (United States)

    Šmidrkal, Jan; Tesařová, Markéta; Hrádková, Iveta; Berčíková, Markéta; Adamčíková, Aneta; Filip, Vladimír

    2016-11-15

    3-MCPD esters are contaminants that can form during refining of vegetable oils in the deodorization step. It was experimentally shown that their content in the vegetable oil depends on the acid value of the vegetable oil and the chloride content. 3-MCPD esters form approximately 2-5 times faster from diacylglycerols than from monoacylglycerols. It has been proved that the higher fatty acids content in the oil caused higher 3-MCPD esters content in the deodorization step. Neutralization of free fatty acids in the vegetable oil before the deodorization step by alkaline carbonates or hydrogen carbonates can completely suppress the formation of 3-MCPD esters. Potassium salts are more effective than sodium salts. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Dissolution patterns of biocompatible glasses in 2-amino-2-hydroxymethyl-propane-1,3-diol (Tris) buffer.

    Science.gov (United States)

    Fagerlund, S; Hupa, L; Hupa, M

    2013-02-01

    A continuous flow measurement system with sensitive on-line ion analysis has been applied to study the initial dissolution behaviour of biocompatible glasses in Tris. Altogether 16 glasses with widely varying compositions were studied. The measurement system allowed for quantitative determination of the time-dependent rates of dissolution of sodium, potassium, calcium, magnesium, silicon and phosphorus during the first 10-15 min in contact with Tris solution. The dissolution rates of the different ions showed significant glass to glass variations, but all glasses studied showed one of four distinct dissolution patterns. The ion dissolution rates after an exposure of 1000 s, expressed as the normalized surface-specific mass loss rates, were compared with the in vitro and in vivo reactivity of the glasses as predicted by models in the literature. The results showed a clear correlation between the dissolution rates of the glasses in Tris and their reactivity as measured by other different methods. Consequently, the measured short-term dissolution patterns could be used to determine which glasses are suitable as bioactive, biodegradable, or inert biomaterials for medical devices. Copyright © 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  5. Efficient Pd@MIL-101(Cr) hetero-catalysts for 2-butyne-1,4-diol hydrogenation exhibiting high selectivity

    KAUST Repository

    Yin, Dongdong; Li, Chuang; Ren, Hangxing; Shekhah, Osama; Liu, Jinxuan; Liang, Changhai

    2017-01-01

    Pd@MIL-101(Cr) hetero-catalysts have been successfully prepared using the metal-organic chemical vapour deposition (MOCVD) approach, by choosing [Pd(η-CH)(η-CH)] as a volatile precursor, and the hydrothermally stable metal-organic framework, MIL-101

  6. Perfluoroalkylated Derivatives of Diols and Triols. Selectivity in the Reaction of Primary and Secondary Hydroxy Groups with Perfluoroalkylepoxides. Hemocompatibility and Effect on Perfluorocarbon Emulsion

    Czech Academy of Sciences Publication Activity Database

    Církva, Vladimír; Polák, R.; Paleta, O.; Kodíček, K.; Forman, S.

    2002-01-01

    Roč. 67, č. 10 (2002), s. 1436-1448 ISSN 0010-0765 R&D Projects: GA ČR GA203/98/1174; GA MŠk LB98233 Keywords : perfluoroalkyl epoxides * fluoroalkylations * fluorophilic triols Subject RIV: CC - Organic Chemistry Impact factor: 0.848, year: 2002

  7. Intercalation of 1,n-diols into strontium phenylphosphonate: How the shape of the host layers influences arrangement of the guest molecules

    Czech Academy of Sciences Publication Activity Database

    Melánová, Klára; Kovář, P.; Beneš, L.; Svoboda, Jan; Veteška, M.; Pospíšil, M.; Zima, Vítězslav

    2015-01-01

    Roč. 460, 15 December (2015), s. 181-188 ISSN 0021-9797 R&D Projects: GA ČR(CZ) GA14-13368S Institutional support: RVO:61389013 Keywords : intercalation * phosphonates * alkaline- earth Subject RIV: CA - Inorganic Chemistry Impact factor: 3.782, year: 2015

  8. Síntesis y caracterización de poliuretanos termoplásticos basados en policarbonato dioles. Relación estructura/propiedades.

    OpenAIRE

    Félix de Castro, Paula

    2012-01-01

    Los poliuretanos son una familia de polímeros muy versátil, utilizados en un amplio rango de aplicación, desde las espumas rígidas-flexibles, materiales elastómeros, recubrimientos, adhesivos, hasta materiales con aplicaciones biomédicas. Esta gran versatilidad es debida a que los reactivos utilizados en la síntesis de los poliuretanos son muy variados, permitiendo la gran versatilidad en la formulación del poliuretano y en las propiedades del mismo. Los poliuretanos termoplásticos el...

  9. Crystal structures of 2-(N,N-dimethylaminoalkyl)ferroceneboronic acids and their diol derivatives. The quest for a B-N intramolecular bond in the solid state

    DEFF Research Database (Denmark)

    Norrild, Jens Chr.; Søtofte, Inger

    2001-01-01

    The crystal structures of (S,S)-2-(N,N-dimethyl-1-aminoethyl)ferroceneboronic acid (2), (S,S)-1-(N,N-dimethyl-1-aminoethyl)-2-(4,4,5,5-tetraphenyl-1,3,2-dioxaborolan-2-yl)ferrocene (3), rac-2-(N,N-dimethylaminomethyl)-ferroceneboronic acid (rac-4), (S)-[(1S,2S,3R,5S)-pinane-1,2-diyl] 2-(N...

  10. Determination of 3-monochloropropane-1,2-diol fatty acid esters in Brazilian vegetable oils and fats by an in-house validated method.

    Science.gov (United States)

    Arisseto, A P; Marcolino, P F C; Vicente, E

    2014-01-01

    An in-house validated GC-MS method preceded by acid-catalysed methanolysis was applied to 97 samples of vegetable oils and fats marketed in Brazil. The levels of the compounds ranged from not detected (limit of detection = 0.05 mg kg(-1)) to 5.09 mg kg(-1), and the highest concentrations were observed in samples containing olive pomace oil and in products used for industrial applications, such as palm oil and its fractions (olein and stearin). The content of diesters and monoesters was also investigated by employing solid-phase extraction on silica cartridges, indicating that the majority of the compounds were present as diesters. This study provides the first occurrence data on these contaminants in Brazil and the results are comparable with those reported in other countries.

  11. Determination of the radioimmunologic concentration of 5-androstene-3β-17β-diole in the blood plasma of patients suffering from common psoriasis

    International Nuclear Information System (INIS)

    Ehlen, M.

    1979-01-01

    A new radioimmunologic method for the determination of ADIOL in the blood plasma was developed. The author produced the antiserum herself and she examined it on cross-reactions. This method resulted to be very sensitive and in the standard curve a linear range of 0.04 ng to 1.5 ng was obtained. Moreover, the ADIOL concentration was determined in the blood plasma of 16 control subjects and of 35 patients suffering from psoriasis. The result was a far-reaching correlation with the results described in literature, although they were obtained by means of differing determination procedures. (orig./MG) [de

  12. Crystal structure of (1S,2R,4S-1-[(morpholin-4-ylmethyl]-4-(prop-1-en-2-ylcyclohexane-1,2-diol

    Directory of Open Access Journals (Sweden)

    Rachid Outouch

    2015-01-01

    Full Text Available The asymmetric unit of the title compound, C14H25NO3, contains two independent molecules with similar geometry. The morpholine and cyclohexane rings of both molecules adopt a chair conformation. Intramolecular O—H...N hydrogen bonds are observed. In the crystal, molecules are linked by O—H...O hydrogen bonds into chains parallel to the [101] direction. The chains are further connected through C—H...O hydrogen bonds forming undulating layers parallel to the (-101 plane. The absolute configuration was assigned by reference to an unchanging chiral centre in the synthetic procedure.

  13. Reaction of a chemotherapeutic agent, 6-mercaptopurine, with a direct-acting, electrophilic carcinogen, benzo[a]pyrene-7,8-diol 9,10-epoxide.

    Science.gov (United States)

    MacLeod, M C; Stewart, E; Daylong, A; Lew, L K; Evans, F E

    1991-01-01

    The chemotherapeutic agent 6-mercaptopurine (6-MP) has been shown to react covalently with the ultimate carcinogenic metabolite of benzo[a]pyrene, 7-r,8-t-dihydroxy-9-t,10-t-oxy-7,8,9,10-tetrahydrobenzo[a]pyrene (BPDE), in aqueous solution, forming a single adduct. NMR studies of the HPLC-purified product were consistent with its identification as 10(S)-(6'-mercaptopurinyl)-7,8,9-trihydroxy-7,8,9,10- tetrahydrobenzo[a]pyrene. Reaction kinetics were analyzed by using both HPLC separation of the products formed and a spectrophotometric assay for adduct formation. A simple model in which direct reaction between 6-MP and BPDE takes place without formation of a physical complex was found to adequately predict the dependence of product ratios on 6-MP concentration. Variations in the observed rate constant for this reaction with changes in temperature, pH, and buffer concentration were determined and compared to the effects of these variables on the observed rate constant for BPDE hydrolysis. In each case, the processes were affected quite differently, suggesting that different rate-determining steps are involved. The data suggest that the reaction mechanism involves SN2 attack of the anion of 6-MP, formed by ionization of the sulfhydryl group, on carbon 10 of BPDE, resulting in a trans-9,10 reaction product.

  14. Covalent binding of benzo(a)pyrene-diol-epoxide to histone H2A in rat liver nuclei: target site specificity

    International Nuclear Information System (INIS)

    Kurokawa, M.; MacLeod, M.C.

    1986-01-01

    The authors have recently found that 7r,8t-dihydroxy-9t,10t-oxy-7,8,9,10-tetrahydrobenzo(a)pyrene (BPDE-I), a strong carcinogen, binds selectively to histone H2A-2 variant in rat liver nuclei, using a high performance liquid chromatography (HPLC) system which can separate H4, H2B, 3 different fractions of H2A variants and 3 different H3 variants in an hour. Here the authors examined the binding site of BPDE-I to the H2A-2 variant. The H2A-2 variants were purified from the acid extracted core histones of rat liver nuclei treated with ( 3 H)-BPDE-I by the HPLC system with a semi-preparative Aquapore RP-300 column. HPLC analysis of cyanogen bromide treated-H2A-2, which has one methionine residue, showed that the binding site is located in C-terminal half of H2A-2. In addition, digestions with V8-protease, trypsin and different types of carboxypeptides suggested that there are some target amino acid residues for BPDE-I in the V8-proteolytic C-terminal octapeptide which contains 2 histadine and 3 lysine residues. Currently identification of the target amino acid is proceeding, using amino acid-BPDE adducts prepared in vitro

  15. Highly Sensitive Determination of 2,4,6-Trinitrotoluene and Related Byproducts Using a Diol Functionalized Column for High Performance Liquid Chromatography

    NARCIS (Netherlands)

    Gümüscü, B.; Erdogan, Zeynep; Guler, Mustafa O.; Tekinay, Turgay

    2016-01-01

    In this work, a new detection method for complete separation of 2,4,6-trinitrotoluene (TNT); 2,4-dinitrotoluene (2,4-DNT); 2,6-dinitrotoluene (2,6-DNT); 2-aminodinitrotoluene (2-ADNT) and 4-aminodinitrotoluene (4-ADNT) molecules in high-performance liquid-chromatography (HPLC) with UV sensor has

  16. Bis(2,2′-bipyridyl-κ2N,N′(sulfato-κ2O,O′cobalt(II ethane-1,2-diol monosolvate

    Directory of Open Access Journals (Sweden)

    Lin Chen

    2011-01-01

    Full Text Available The title compound, [Co(SO4(C10H8N22]·C2H6O2, has the Co2+ ion in a distorted octahedral CoN4O2 coordination geometry. A twofold rotation axis passes through the Co and S atoms, and through the mid-point of the C—C bond of the ethanediol molecule. In the crystal, the [CoSO4(C10H8N22] and C2H6O2 units are held together by a pair of O—H...O hydrogen bonds.

  17. Efficient Synthesis of Differentiated syn-1,2-Diol Derivatives by Asymmetric Transfer Hydrogenation-Dynamic Kinetic Resolution of α-Alkoxy-Substituted β-Ketoesters.

    Science.gov (United States)

    Monnereau, Laure; Cartigny, Damien; Scalone, Michelangelo; Ayad, Tahar; Ratovelomanana-Vidal, Virginie

    2015-08-10

    Asymmetric transfer hydrogenation was applied to a wide range of racemic aryl α-alkoxy-β-ketoesters in the presence of well-defined, commercially available, chiral catalyst Ru(II) -(N-p-toluenesulfonyl-1,2-diphenylethylenediamine) and a 5:2 mixture of formic acid and triethylamine as the hydrogen source. Under these conditions, dynamic kinetic resolution was efficiently promoted to provide the corresponding syn α-alkoxy-β-hydroxyesters derived from substituted aromatic and heteroaromatic aldehydes with a high level of diastereoselectivity (diastereomeric ratio (d.r.)>99:1) and an almost perfect enantioselectivity (enantiomeric excess (ee)>99 %). Additionally, after extensive screening of the reaction conditions, the use of Ru(II) - and Rh(III) -tethered precatalysts extended this process to more-challenging substrates that bore alkenyl-, alkynyl-, and alkyl substituents to provide the corresponding syn α-alkoxy-β-hydroxyesters with excellent enantiocontrol (up to 99 % ee) and good to perfect diastereocontrol (d.r.>99:1). Lastly, the synthetic utility of the present protocol was demonstrated by application to the asymmetric synthesis of chiral ester ethyl (2S)-2-ethoxy-3-(4-hydroxyphenyl)-propanoate, which is an important pharmacophore in a number of peroxisome proliferator-activated receptor α/γ dual agonist advanced drug candidates used for the treatment of type-II diabetes. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. hREV3 is essential for error-prone translesion synthesis past UV or benzo[a]pyrene diol epoxide-induced DNA lesions in human fibroblasts

    Energy Technology Data Exchange (ETDEWEB)

    Li Ziqiang; Zhang Hong; McManus, Terrence P.; McCormick, J. Justin; Lawrence, Christopher W.; Maher, Veronica M

    2002-12-29

    In S. cerevisiae, the REV3 gene, encoding the catalytic subunit of polymerase zeta, is involved in translesion synthesis and required for the production of mutations induced by ultraviolet radiation (UV) photoproducts and other DNA fork-blocking lesions, and for the majority of spontaneous mutations. To determine whether hREV3, the human homolog of yeast REV3, is similarly involved in error-prone translesion synthesis past UV photoproducts and other lesions that block DNA replication, an hREV3 antisense construct under the control of the TetP promoter was transfected into an infinite life span human fibroblast cell strain that expresses a high level of tTAk, the activator of that promoter. Three transfectant strains expressing high levels of hREV3 antisense RNA were identified and compared with their parental cell strain for sensitivity to the cytotoxic and mutagenic effects of UV. The three hREV3 antisense-expressing cell strains were not more sensitive than the parental strain to the cytotoxic effect of UV, but the frequency of mutants induced by UV in their HPRT gene was significantly reduced, i.e. to 14% that of the parent. Two of these hREV3 antisense-expressing cell strains were compared with the parental strain for sensitivity to ({+-})-7{beta},8{alpha}-dihydroxy-9{alpha},10{alpha}-epoxy-7,8,9,10-tetrahydro= benzo[a]pyrene (BPDE). They were not more sensitive than the parent strain to the cytotoxic effect of BPDE, but the frequency of mutants induced was significantly reduced, i.e. in one strain, to 17% that of the parent, and in the other, to 24%. DNA sequencing showed that the kinds of mutations induced by BPDE in the parental and the derivative strains did not differ and were similar to those found previously with finite life span human fibroblasts. The data strongly support the hypothesis that hRev3 plays a critical role in the induction of mutations by UV or BPDE. Because the level of hRev3 protein in human fibroblasts is below the level of antibody detection, it was not possible to demonstrate that the decrease in mutagenesis reflected decreased hRev3 protein. However, the conclusion is supported by the fact that in a similar study with a strain expressing a high level of antisense hREV1, a very similar result was obtained, i.e. UV or BPDE mutagenesis was virtually eliminated.

  19. hREV3 is essential for error-prone translesion synthesis past UV or benzo[a]pyrene diol epoxide-induced DNA lesions in human fibroblasts

    International Nuclear Information System (INIS)

    Li Ziqiang; Zhang Hong; McManus, Terrence P.; McCormick, J. Justin; Lawrence, Christopher W.; Maher, Veronica M.

    2002-01-01

    In S. cerevisiae, the REV3 gene, encoding the catalytic subunit of polymerase zeta, is involved in translesion synthesis and required for the production of mutations induced by ultraviolet radiation (UV) photoproducts and other DNA fork-blocking lesions, and for the majority of spontaneous mutations. To determine whether hREV3, the human homolog of yeast REV3, is similarly involved in error-prone translesion synthesis past UV photoproducts and other lesions that block DNA replication, an hREV3 antisense construct under the control of the TetP promoter was transfected into an infinite life span human fibroblast cell strain that expresses a high level of tTAk, the activator of that promoter. Three transfectant strains expressing high levels of hREV3 antisense RNA were identified and compared with their parental cell strain for sensitivity to the cytotoxic and mutagenic effects of UV. The three hREV3 antisense-expressing cell strains were not more sensitive than the parental strain to the cytotoxic effect of UV, but the frequency of mutants induced by UV in their HPRT gene was significantly reduced, i.e. to 14% that of the parent. Two of these hREV3 antisense-expressing cell strains were compared with the parental strain for sensitivity to (±)-7β,8α-dihydroxy-9α,10α-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene (BPDE). They were not more sensitive than the parent strain to the cytotoxic effect of BPDE, but the frequency of mutants induced was significantly reduced, i.e. in one strain, to 17% that of the parent, and in the other, to 24%. DNA sequencing showed that the kinds of mutations induced by BPDE in the parental and the derivative strains did not differ and were similar to those found previously with finite life span human fibroblasts. The data strongly support the hypothesis that hRev3 plays a critical role in the induction of mutations by UV or BPDE. Because the level of hRev3 protein in human fibroblasts is below the level of antibody detection, it was not possible to demonstrate that the decrease in mutagenesis reflected decreased hRev3 protein. However, the conclusion is supported by the fact that in a similar study with a strain expressing a high level of antisense hREV1, a very similar result was obtained, i.e. UV or BPDE mutagenesis was virtually eliminated.

  20. Twenty-six-week oral carcinogenicity study of 3-monochloropropane-1,2-diol in CB6F1-rasH2 transgenic mice.

    Science.gov (United States)

    Lee, Byoung-Seok; Park, Sang-Jin; Kim, Yong-Bum; Han, Ji-Seok; Jeong, Eun Ju; Son, Hwa-Young; Moon, Kyoung-Sik

    2017-01-01

    The carcinogenic potential of 3-monochloro-1,2-propanediol (3-MCPD) was evaluated in a short-term carcinogenicity testing study using CB6F1 rasH2-Tg (rasH2-Tg) mice. 3-MCPD is found in many foods and food ingredients as a result of storage or processing and is regarded as a carcinogen since it is known to induce Leydig cell and kidney tumors in rats. Male and female rasH2-Tg mice were administered 3-MCPD once daily by oral gavage at doses of 0, 10, 20, and 40 mg/kg body weight (bw) per day for 26 weeks. As a positive control, N-methyl-N-nitrosourea (MNU) was administered as a single intraperitoneal injection (75 mg/kg). In 3-MCPD-treated mice, there was no increase in the incidence of neoplastic lesions compared to the incidence in vehicle control mice. However, 3-MCPD treatment resulted in an increased incidence of tubular basophilia in the kidneys and germ cell degeneration in the testes, with degenerative germ cell debris in the epididymides of males at 20 and 40 mg/kg bw per day. In 3-MCPD-treated females, vacuolation of the brain and spinal cord was observed at 40 mg/kg bw per day; however, only one incidence of vacuolation was observed in males. Forestomach and cutaneous papilloma and/or carcinoma and lymphoma were observed in most rasH2 mice receiving MNU treatment. We concluded that 3-MCPD did not show carcinogenic potential in the present study using rasH2-Tg mice. The findings of this study suggest that the carcinogenic potential of 3-MCPD is species specific.

  1. Diols and anions can control the formation of an exciplex between a pyridinium boronic acid with an aryl group connected via a propylene linker.

    Science.gov (United States)

    Huang, Yan-Jun; Jiang, Yun-Bao; Bull, Steven D; Fossey, John S; James, Tony D

    2010-11-21

    The exciplex formation between a pyridinium boronic acid and phenyl group connected via a propylene linker can be monitored using fluorescence. Addition of pinacol affords a cyclic boronate ester with enhanced Lewis acidity that increases the strength of its cation-π stacking interaction causing a four-fold fluorescence enhancement.

  2. 17α-Ethyl-5β-estrane-3α,17β-diol, a biological marker for the abuse of norethandrolone and ethylestrenol in slaughter cattle

    NARCIS (Netherlands)

    Puymbroeck, M. van; Kuilman, M.E.M.; Maas, R.F.M.; Witkamp, R.F.; Leyssens, L.; Miert, A.S.J.P.A.M. van; Hendriks, L.; Zande, D.J.M. van der; Adriaensens, P.; Jacobs, M.-P.; Raus, J.

    1999-01-01

    The metabolism of the illegal growth promoter ethylestrenol (EES) was evaluated in bovine liver cells and subcellular fractions of bovine liver preparations. Incubations with bovine microsomal preparations revealed that EES is extensively biotransformed into norethandrolone (NE), another illegal

  3. TPX2 in malignantly transformed human bronchial epithelial cells by anti-benzo[a]pyrene-7,8-diol-9,10-epoxide

    International Nuclear Information System (INIS)

    Zhang Lijuan; Huang He; Deng Luyao; Chu Ming; Xu Lan; Fu Juanling; Zhu Yunlan; Zhang Xiuchun; Liu Shulin; Zhou Zongcan; Wang Yuedan

    2008-01-01

    In order to elucidate the function of the targeting protein for Xenopus kinesin-like protein 2 (Xklp2) (TPX2) in the malignant transformation of human bronchial epithelial cells induced by anti-benzo[a]pyrene-trans-7, 8-dihydrodiol-9, 10-epoxide (anti-BPDE), TPX2 was characterized in cells at both the gene and the protein levels. TPX2 was present at higher levels in 16HBE-C cells than in 16HBE cells as demonstrated by two-dimensional gel electrophoresis, immunocytochemistry, Western blot analysis and RT-PCR. TPX2 was also detected in lung squamous-cell carcinoma tissues by immunohistochemistry, but not in normal lung tissues. Depression of TPX2 by RNA interference in 16HBE-C cells led to a decrease in cell proliferation, S-phase cell cycle arrest and cell apoptosis. Abnormal TPX2 tyrosine phosphorylation was detected in 16HBE-C cells, and this could be inhibited, to different degrees, by tyrosine kinase inhibitors. Inhibiting tyrosine phosphorylation in 16HBE-C cells by three selected tyrosine protein kinase inhibitors, tyrphostin 47, AG112 and AG555, caused G 0 /G 1 -phase cell cycle arrest. Our results suggest that anti-BPDE can cause the over-expression of TPX2 and its aberrant tyrosine phosphorylation. Misregulation of TPX2 affects the cell cycle state, proliferation rates and apoptosis

  4. Synthesis, thermolysis and pyrolysis of group IV metal pinacolates: The impact of a vicinal diol as a supporting ligand for molecular precursors

    Science.gov (United States)

    Zechmann, Cecilia A.

    In an effort to investigate the suitability of an alternative ligand class for molecular precursors, the following studies were carried out: (1) New zirconium species were obtained by reaction of zirconium isopropoxide alcoholate, Zr2(OiPr)8(HOiPr) 2, with pinacol (HOCMe2CMe2OH). Control of reaction stoichiometries followed by azeotropic distillation of evolved isopropanol led to the successful preparation of a range of homo- and heteroleptic trinuclear species, Zr3(OCMe2CMe2O)2(O iPr)8(HOiPr)2, Zr3(OCMe 2CMe2O)4(OCMe2CMe2OH) 2(OiPr)2, and Zr3(OCMe2CMe 2O)4(OCMe2CMe2OH)4. Dinuclear products could be obtained by carrying out the reactions at room temperature or by addition of excess pinacol (in which case Zr2(OCMe2 CMe2O)2(OCMe2CMe2OH) 4 was the product). (2) Similar reactions between Ti(Oi Pr)4 and pinacol gave dinuclear products under all conditions. Both homo- (Ti2(OiPr)2(OCMe2CMe 2O)2(OCMe2CMe2OH)2) and heterometallic complexes (Ti2(OCMe2CMe2O) 2(OCMe2CMe2OH)4) were characterized. (3) Controlled addition of water to either of the isolated titanium pinacolates gave Ti3(mu3-O)(OCMe2CMe2O) 4(OCMe2CMe2OH)2. (4) Reaction of zirconium pinacolates with water led to the isolation of Zr4(mu 2-O)(OCMe2CMe2O)4(OCMe2CMe 2OH)6 and Zr6(mu3-O)4(H 2O)2(OCMe2CMe2O)5(OCMe 2CMe2OH)5. 17O NMR studies aided in the investigation of active equilibria and reversibility of hydrolysis. (5) The thermolysis of Zr2(OCMe2CMe2O) 2(OCMe2CMe2OH)4 gave ZrO2 in a mixture of crystalline phases. GC-MS and NMR analysis of the volatiles revealed 4 C6 products as well as two ligand coupled products. Isotope-labeling studies were carried out to probe the mechanisms by which the organic products were formed. (6) Reaction of Zr2(OCMe 2CMe2O)2(OCMe2CMe2OH) 4 with Ti(OiPr)4 gives (OiPr) 2TiZr2(OCMe2CMe2O)4(OCMe 2CMe2OH)2 which reacts with a second equivalent of Ti(OiPr)4 to give (OiPr) 4Ti2Zr2(OCMe2CMe2O) 6. (7) Reaction of Li{N(SiMe3)2}·Et 2O or Na{N(SiMe3)2}·x THF with Zr2(OCMe2CMe2O)2(OCMe 2CMe2OH)4 gave (THF)LiZr2(OCMe 2CMe2O)3(OCMe2CMe2OH) 3 or (HOCMe2CMe2OH)2Na2Zr 2(OCMe2CMe2O)4(OCMe2CMe 2OH)2 respectively. Similar reactions with larger +1 or +2 metals led to the formation of insoluble precipitates.

  5. 5,7,12,14-Tetrahydro-5,14:7,12-bis([1,2]benzenopentacene-6,13-diol dimethylformamide disolvate

    Directory of Open Access Journals (Sweden)

    Mohammad Nozari

    2016-07-01

    Full Text Available The crystal lattice of the title compound, C34H22O2·2C3H7NO, at 173 K has monoclinic (P21/n symmetry. Molecules are located on crystallographic centers of symmetry and have approximate non-crystallographic mmm symmetry, indicating that in solution the chemical and spectroscopic behavior would be that of a D2h molecule. The compound has applications in gas-separation membranes fabricated from polymers of intrinsic microporosity (PIM. The compound is the product of reduction of the corresponding quinone by Na2S2O4 in DMF/NaHCO3.

  6. Analysis of 1,2-diol diesters in vernix caseosa by high-performance liquid chromatography - atmospheric pressure chemical ionization mass spectrometry

    Czech Academy of Sciences Publication Activity Database

    Šubčíková, L.; Hoskovec, Michal; Vrkoslav, Vladimír; Čmelíková, T.; Háková, Eva; Míková, Radka; Coufal, P.; Doležal, A.; Plavka, R.; Cvačka, Josef

    2015-01-01

    Roč. 1378, Jan 23 (2015), s. 8-18 ISSN 0021-9673 R&D Projects: GA ČR GAP206/12/0750 Institutional support: RVO:61388963 Keywords : skin lipids * neutral lipids * lipidomics * mass spectrometry * double-bond position Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 3.926, year: 2015

  7. The C

    NARCIS (Netherlands)

    Lattaud, J.; Kim, J.-H; de Jonge, C.; Zell, C.; Sinninghe Damsté, J.S.; Schouten, S.

    2017-01-01

    Long chain alkyl diols are lipids that occur ubiquitously in marine sediments and are used as a proxy for sea surface temperature (SST), using the Long chain Diol Index (LDI), and for upwelling intensity/high nutrient conditions. The distribution of 1,13- and 1,15-diols has been documented in open

  8. elucidating the mechanism of the adsorption of mucin

    African Journals Online (AJOL)

    dcu user

    Kinetic and mechanistic studies of electron transfer reaction of butane-1,3-diol and Cr(VI) ion in ... The oxidation of diols other than. 1,2-diols by transition metal ions and their complexes has received little attention. An increased interest in these reactions was noticed after the oxidation of propane-1,3-, butane-1,3- and ...

  9. Kinetics and mechanism of the oxidation of some vicinal and non ...

    Indian Academy of Sciences (India)

    Kinetics of oxidation of five vicinal and four non-vicinal diols, and two of their monoethers, by tetrabutylammonium tribromide (TBATB) has been studied. The vicinal diols yield products arising out of glycol-bond fission, while the non-vicinal diols produce the hydroxycarbonyl compounds. The reaction is first-order with ...

  10. Producció enantioselectiva de diols vicinals i αhidroxicetones amb oxidoreductases de llevat. Aplicació de tècniques d’autoclonació per la generación d’enzims i soques modificades

    OpenAIRE

    Calam Cervera, Eduard

    2015-01-01

    Les transformacions catalitzades per enzims s'utilitzen cada cop més per a la síntesis d'intermediaris útils destinats a les indústries farmacèutiques, agroalimentàries i de química fina. La utilització d'enzims en síntesi química compleix amb els principis de la "química verda", com per exemple en la utilització de solvents més segurs (les reaccions enzimàtiques són realitzades usualment, en medi aquós), en el disseny de reaccions amb millor eficiència energètica (les reaccions enzimàtiques ...

  11. Flow cytometric analysis of mitotic cycle perturbation by chemical carcinogens in cultured epithelial cells. [Effects of benzo(a)pyrene-diol-epoxide on mitotic cycle of cultural mouse liver epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Pearlman, Andrew Leonard [Univ. of California, Berkeley, CA (United States)

    1978-08-01

    A system for kinetic analysis of mitotic cycle perturbation by various agents was developed and applied to the study of the mitotic cycle effects and dependency of the chemical carcinogen benzo(a)pyrene-diolepoxide, DE, upon a mouse lever epithelial cell line, NMuLi. The study suggests that the targets of DE action are not confined to DNA alone but may include cytoplasmic structures as well. DE was found to affect cells located in virtually every phase of the mitotic cycle, with cells that were actively synthesizing DNA showing the strongest response. However, the resulting perturbations were not confined to S-phase alone. DE slowed traversal through S-phase by about 40% regardless of the cycle phase of the cells exposed to it, and slowed traversal through G2M by about 50%. When added to G1 cells, DE delayed recruitment of apparently quiescent (G0) cells by 2 hours, and reduced the synchrony of the cohort of cells recruited into active proliferation. The kinetic analysis system consists of four elements: tissue culture methods for propagating and harvesting cell populations; an elutriation centrifugation system for bulk synchronization of cells in various phases of the mitotic cycle; a flow cytometer (FCM), coupled with appropriate staining protocols, to enable rapid analysis of the DNA distribution of any given cell population; and data reduction and analysis methods for extracting information from the DNA histograms produced by the FCM. The elements of the system are discussed. A mathematical analysis of DNA histograms obtained by FCM is presented. The analysis leads to the detailed implementation of a new modeling approach. The new modeling approach is applied to the estimation of cell cycle kinetic parameters from time series of DNA histograms, and methods for the reduction and interpretation of such series are suggested.

  12. Radical Addition Reactions of Fluorinated Species. Part 8. Rigioselectivity of Radical Additions to Perfluoroalkylethylenes and Quantum Chemical Calculations. Highly Selective Two-Step Synthesis of 4-(Perfluoroalkyl)Butane-1,2-diols

    Czech Academy of Sciences Publication Activity Database

    Církva, Vladimír; Böhm, S.; Paleta, O.

    2000-01-01

    Roč. 102, - (2000), s. 159-168 ISSN 0022-1139 R&D Projects: GA ČR GA203/98/1174; GA MŠk LB98233 Institutional research plan: CEZ:AV0Z4072921 Subject RIV: CC - Organic Chemistry Impact factor: 0.851, year: 2000

  13. A Multidisciplinary Approach Toward the Rapid and Preparative-Scale Biocatalytic Synthesis of Chiral Amino Alcohols: A Concise Transketolase-/omega-Transaminase-Mediated Synthesis of (2S,3S)-2-Aminopentane-1,3-diol

    DEFF Research Database (Denmark)

    Smith, M.E.B; Chen, B.H.; Hibbert, E.G

    2010-01-01

    Chiral amino alcohols represent an important class of value-added biochemicals and pharmaceutical intermediates. Chemical routes to such compounds are generally step intensive, requiring environmentally unfriendly catalysts and solvents. This work describes a multidisciplinary approach to the rapid...... the bioconversions were subsequently scaled up to preparative scales in batch stirred-tank reactors. The microwell methods thus provide process chemists and engineers with a valuable tool for the rapid and early evaluation of potential synthetic strategies. Overall, this work describes a concise and efficient...... biocatalytic route to chiral amino alcohols and illustrates an integrated multidisciplinary approach to bioconversion process design and scale-up....

  14. CCDC 838941: Experimental Crystal Structure Determination : 3,3,3',3'-Tetramethyl-5,5'-dinitro-2,2',3,3'-tetrahydro-1,1'-spirobi[indene]-6,6'-diol dichloromethane solvate

    KAUST Repository

    Ma, Xiaohua; Swaidan, R.; Belmabkhout, Youssef; Zhu, Yihan; Litwiller, E.; Jouiad, M.; Pinnau, I.; Han, Yu

    2013-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  15. Crystal structure of 5,5′-dibromo-3,3′-di-tert-butyl-6,6′-dimethylbiphenyl-2,2′-diol

    Directory of Open Access Journals (Sweden)

    Rika Obata

    2015-05-01

    Full Text Available The whole molecule of the title compound, C22H28Br2O2, is generated by twofold rotation symmetry. The dihedral angle of the biphenyl moiety is 85.05 (11°. The hydroxy groups show intramolecular O—H...π interactions without any other hydrogen-bond acceptors. In the crystal, there are no other significant intermolecular interactions present.

  16. Synthesis, spectral, antitumor, antioxidant and antimicrobial studies on Cu(II), Ni(II) and Co(II) complexes of 4-[(1H-Benzoimidazol-2-ylimino)-methyl]-benzene-1,3-diol.

    Science.gov (United States)

    El-wakiel, Nadia; El-keiy, Mai; Gaber, Mohamed

    2015-08-05

    A new Schiff base of 2-aminobenzimidazole with 2,4-dihydroybezaldehyde (H₃L), and its Cu(II), Ni(II) and Co(II) complexes have been synthesized and characterized by elemental analyses, molar conductance, thermal analysis (TGA), inductive coupled plasma (ICP), magnetic moment measurements, IR, EI-mass, UV-Vis. and ESR spectral studies. On the basis of spectral studies and analytical data, it is evident that the Schiff base acts as dibasic tridentate ligand coordinating via deprotonated OH, NH and azomethine nitrogen atom. The results showed that Co(II) and Ni(II) complexes have tetrahedral structure while Cu(II) complexes has octahedral geometry. The kinetic and thermodynamic parameters of the thermal decomposition stages have been evaluated. The studied complexes were tested for their in vitro antimicrobial activities against some bacterial strains. The anticancer activity of the ligand and its metal complexes is evaluated against human liver Carcinoma (HEPG2) cell. These compounds exhibited a moderate and weak activity against the tested HEPG2 cell lines with IC₅₀ of 9.08, 18.2 and 19.7 μg/ml for ligand, Cu(II) and Ni(II) complexes, respectively. In vitro antioxidant activity of the newly synthesized compounds has also been evaluated. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Novel mixed ligand complexes of bioactive Schiff base (E)-4-(phenyl (phenylimino) methyl) benzene-1,3-diol and 2-aminophenol/2-aminobenzoic acid: Synthesis, spectral characterization, antimicrobial and nuclease studies

    Science.gov (United States)

    Subbaraj, P.; Ramu, A.; Raman, N.; Dharmaraja, J.

    2014-01-01

    A novel bidentate Schiff base ligand has been synthesized using 2,4-dihydroxybenzophenone and aniline. Its mixed ligand complexes of MAB type [M = Mn(II), Co(II), Ni(II), Cu(II) and Zn(II); HA = Schiff base and B = 2-aminophenol/2-aminobenzoic acid] have been synthesized and characterized on the basis of spectral data UV-Vis, IR, 1H NMR, FAB-Mass, EPR, SEM and magnetic studies. All the complexes were soluble in DMF and DMSO. Elemental analysis and molar conductance values indicate that the complexes are non-electrolytes. HA binds with M(II) ions through azomethine and deprotonated phenolic group and B binds through the primary amine group and deprotonated phenolic/carboxylic groups. Using FAB-Mass the cleavage pattern of the ligand (HA) has been established. All the complexes adopt octahedral geometry around the metal ions. It has been confirmed with the help of UV-Vis, IR, 1H NMR and FAB-Mass spectral data. DNA binding activities of the complexes 1d and 2d are studied by UV-Vis spectroscopy and cleavage studies of Schiff base ligand and its complexes 1d and 2d have been by agarose gel electrophoresis method. In vitro biological activities of the free ligand (HA) and their metal complexes (1a-1e and 2a-2e) were screened against few bacteria, Escherichia coli, Staphylococcus saphyphiticus, Staphylococcus aureus, Pseudomonas aeruginosa and fungi Aspergillus niger, Enterobacter species, Candida albicans by well diffusion technique.

  18. A 28-day oral gavage toxicity study of 3-monochloropropane-1,2-diol (3-MCPD) in CB6F1-non-Tg rasH2 mice.

    Science.gov (United States)

    Lee, Byoung-Seok; Park, Sang-Jin; Kim, Yong-Bum; Han, Ji-Seok; Jeong, Eun-Ju; Moon, Kyoung-Sik; Son, Hwa-Young

    2015-12-01

    3-Monochloro-1,2-propanediol (3-MCPD) is a well-known contaminant of foods containing hydrolyzed vegetable protein. However, limited toxicity data are available for the risk assessment of 3-MCPD and its carcinogenic potential is controversial. To evaluate the potential toxicity and determine the dose levels for a 26-week carcinogenicity test using Tg rasH2 mice, 3-MCPD was administered once daily by oral gavage at doses of 0, 25, 50, and 100 mg/kg body weight (b.w.)/day for 28 days to male and female CB6F1-non-Tg rasH2 mice (N = 5 males and females per dose). The standard toxicological evaluations were conducted during the in-life and post-mortem phase. In the 100 mg/kg b.w./day group, 3 males and 1 female died during the study and showed clinical signs such as thin appearance and subdued behavior accompanied by significant decreases in mean b.w. Microscopy revealed tubular basophilia in the kidneys, exfoliated degenerative germ cells in the lumen of the seminiferous tubule of the testes, vacuolation in the brain, axonal degeneration of the sciatic nerve, and cardiomyopathy in the 100, ≥25, ≥50, 100, and 100 mg/kg b.w./day groups, respectively. In conclusion, 3-MCPD's target organs were the kidneys, testes, brain, sciatic nerve, and heart. The "no-observed-adverse-effect level" (NOAEL) of 3-MCPD was ≤25 and 25 mg/kg b.w./day in males and females, respectively. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Co-crystal of (R,R)-1,2-cyclohexanediol with (R,R)-tartaric acid, a key structure in resolution of the ({+-})-trans-diol by supercritical extraction, and the related ternary phase system

    Energy Technology Data Exchange (ETDEWEB)

    Thorey, Paul [Department of Chemical and Environmental Process Engineering, Budapest University of Technology and Economics, H-1521 Budapest (Hungary); Bombicz, Petra [Institute of Structural Chemistry, Chemical Research Center, Hungarian Academy of Science, H-1525 Budapest (Hungary); Szilagyi, Imre Miklos [Material Structure and Modeling Research Group, Hungarian Academy of Sciences, H-1111 Budapest (Hungary); Department of Inorganic and Analytical Chemistry, Budapest University of Technology and Economics, H-1521 Budapest (Hungary); Molnar, Peter; Bansaghi, Gyoergy; Szekely, Edit; Simandi, Bela [Department of Chemical and Environmental Process Engineering, Budapest University of Technology and Economics, H-1521 Budapest (Hungary); Parkanyi, Laszlo [Institute of Structural Chemistry, Chemical Research Center, Hungarian Academy of Science, H-1525 Budapest (Hungary); Pokol, Gyoergy [Department of Inorganic and Analytical Chemistry, Budapest University of Technology and Economics, H-1521 Budapest (Hungary); Madarasz, Janos, E-mail: madarasz@mail.bme.hu [Department of Inorganic and Analytical Chemistry, Budapest University of Technology and Economics, H-1521 Budapest (Hungary)

    2010-01-10

    A novel co-crystal of trans-(R,R)-1,2-cyclohexanediol and (R,R)-tartaric acid (with 1:1 molar ratio, 1) has been found to be a key crystalline compound in the improved resolution of ({+-})-trans-1,2-cyclohexanediol by supercritical fluid extraction. The molecular and crystal structure of this co-crystal, which crystallizes in orthorhombic crystal system (space group P2{sub 1}2{sub 1}2{sub 1}, a = 6.7033(13) A, b = 7.2643(16), c = 24.863(5), Z = 4), has been solved by single crystal X-ray diffraction (R = 0.064). The packing arrangement consists of two dimensional layers of sandwich-like sheets, where the inner part is constructed by double layers of tartaric acids which hydrophilicity is 'covered' on both upper and bottom side by cyclohexanediols with the hydrophobic cyclohexane rings pointing outward. Thus, a rather complex hydrogen bonding pattern is constructed. The relatively high melting point (133 {sup o}C) observed by both simultaneous TG/DTA and DSC, and the main features of FTIR-spectrum of 1 are explained by the increased stability of this crystal structure. DSC studies on binary mixtures of co-crystal 1 with (R,R)-1,2-cyclohexanediol or (R,R)-tartaric acid, revealed eutectic temperatures of T{sub eu} = 100 or 131 {sup o}C, respectively. Between (S,S)-1,2-cyclohexanediol and (R,R)-tartaric acid a eutectic temperature of T{sub eu} = 85 {sup o}C have also been observed. The phase relations have been confirmed by powder X-ray diffraction, as well.

  20. Metabolic activation and DNA binding of benzo(a)pyrene in cultured human bronchus

    DEFF Research Database (Denmark)

    Yang, Shen K.; Gelboin, Harry V.; Trump, Benjamin F.

    1977-01-01

    . The predominant metabolite formed by human bronchus from the (-)-trans-7,8-diol is found by high-pressure liquid chromatographic analysis to be the diol-epoxide r-7,t-8-dihydroxy-t-9,10-oxy-7,8,9,10-tetrahy-drobenzo(a)pyrene. The results suggest that this diol-epoxide is the major benzo(a)pyrene metabolite bound...

  1. Humanized Androgen Receptor Mice: A Genetic Model for Differential Response to Prostate Cancer Therapy

    Science.gov (United States)

    2012-07-01

    of T, DHT and its two principal metabolites 5a-androstane-3a,17bDiol (3aDiol) and 5a-androstane- 3b,17bDiol (3bDiol) were measured in extracts of 50 ll ...intact) or 100 ll (DHT-treated) of mouse serum by liquid chromatography tandem mass spectrometry (LC–MS/MS) (Harwood and Handels- man, 2009) as...is activated by adrenal androgens and progesterone. Mol. Endocrinol. 7, 1541–1550. David, C.J., Manley , J.L., 2010. Alternative pre-mRNA splicing

  2. Three New Multiflorane-Type Triterpenes from Pumpkin (Cucurbita maxima Seeds

    Directory of Open Access Journals (Sweden)

    Reiko Tanaka

    2013-05-01

    Full Text Available Three new multiflorane-type triterpenes; 7a-methoxymultiflor-8-ene-3a,29-diol 3-acetate-29-benzoate (1, 7-oxomultiflor-8-ene-3a,29-diol 3-acetate-29-benzoate (2, and multiflora-7,9(11-diene-3a,29-diol 3-p-hydroxybenzoate-29-benzoate (3, were isolated from seeds of Cucurbita maxima, along with three known compounds. Compound 3 and multiflora-7,9(11-diene-3a-29-diol 3-benzoate (5 exhibited potent inhibitory effects on melanogenesis, with low cytotoxicities, and 2 exhibited single-digit micromolar cytotoxicity against HL-60 and P388 cells.

  3. Three new multiflorane-type triterpenes from pumpkin (Cucurbita maxima) seeds.

    Science.gov (United States)

    Kikuchi, Takashi; Takebayashi, Mika; Shinto, Mayumi; Yamada, Takeshi; Tanaka, Reiko

    2013-05-14

    Three new multiflorane-type triterpenes; 7a-methoxymultiflor-8-ene-3a,29-diol 3-acetate-29-benzoate (1), 7-oxomultiflor-8-ene-3a,29-diol 3-acetate-29-benzoate (2), and multiflora-7,9(11)-diene-3a,29-diol 3-p-hydroxybenzoate-29-benzoate (3), were isolated from seeds of Cucurbita maxima, along with three known compounds. Compound 3 and multiflora-7,9(11)-diene-3a-29-diol 3-benzoate (5) exhibited potent inhibitory effects on melanogenesis, with low cytotoxicities, and 2 exhibited single-digit micromolar cytotoxicity against HL-60 and P388 cells.

  4. Proceedings of the International Pyrotechnics Seminar (6th) Held at Estes Park, Colorado, 17-21 July 1978

    Science.gov (United States)

    1978-06-01

    ethylene glycols , neopentyl - glycol , 1,6-hexane-diol, and similar diols. Polyesters are generally preferred over polyethers because they are able to retain...contribute to adequate processing, mech- anical properties, and ballistics. The CT polydiethylene glycol adipate i cured with the multifunctional ERL

  5. Preparation of eugenol-based polyurethane

    Science.gov (United States)

    Li, Yupeng; Luo, Fang; Cheng, Chuanjie

    2018-03-01

    The regenerative eugenol was used as the starting material to prepare diol species by two steps, with a total yield of 28%. Furthermore, the prepared diol reacts with 1,6-hexadiisocyanate(HDI) to afford the corresponding polyurethane (PU). The structure of intermediates and PU are characterized by 1H-NMR or IR.

  6. One-Pot Catalyst-Free Synthesis of β- and γ-Hydroxy Sulfides using Diaryliodonium Salts and Microwave Irradiation

    Science.gov (United States)

    A facile one-pot high-yield protocol is described for the preparation of β- and γ-hydroxy sulfides directly from diaryliodonium salts, potassium thiocyanate, and ethane-1,2-diol (ethylene glycol)/propane-1,3-diol (β-propylene glycol) without the need for any additional catalyst o...

  7. Isolation and Structure Elucidation of Radical Scavengers from Thymus vulgaris Leaves

    NARCIS (Netherlands)

    Dapkevicius, A.; Beek, van T.A.; Lelyveld, G.P.; Veldhuizen, van A.; Groot, de Æ.; Linssen, J.P.H.; Venskutonis, R.

    2002-01-01

    2,2-Diphenyl-1-picrylhydrazyl radical (DPPH*) scavenging activity-guided fractionation of a leaf extract of Thymus vulgaris led to the isolation of the radical scavengers rosmarinic acid 1, eriodictyol, taxifolin, luteolin 7-glucuronide, p-cymene 2,3-diol, p-cymene 2,3-diol 6-6'-dimer, carvacrol,

  8. Estudo fitoquímico da madeira de Guarea macrophylla (Meliaceae Phytochemical study of the wood from Guarea macrophylla (Meliaceae

    Directory of Open Access Journals (Sweden)

    João Henrique G. Lago

    2009-01-01

    Full Text Available In the present work, the crude ethanol extract from wood of G. macrophylla was submitted to liquid/liquid partition between hexane, CH2Cl2, EtOAc and n-BuOH. Each phase was individually chromatographed over silica gel, Sephadex LH-20 or Amberlite XAD-2 to give eight terpene derivatives, such as five sesquiterpenoids (caryophyllene oxide, guai-6-en-10β-ol, spathulenol, aromadendrane-4β,10α-diol and aloaromadendrane-4α,10β-diol as well as three triterpenoids (cicloart-24-ene-3β,23(R*-diol, cicloart-24-ene-3β,23(S*-diol, and cicloart-23E-ene-3β,25-diol. Additionally, were isolated three fatty acids (linolenic, linoleic and stearic, two steroids (sitosterol and stigmasterol and sacarose. The structures of all these compounds were characterized by spectrometric analysis, mainly mass spectrometry and NMR and comparison of these data described in the literature.

  9. Synthesis, estrogen receptor binding, and tissue distribution of a new iodovinylestradiol derivative (17{alpha},20E)-21-[{sup 123}I]iodo-11{beta}-nitrato-19-norpregna-1,3,5(10),20-te= traene-3,17 -diol (E-[{sup 123}I]NIVE)

    Energy Technology Data Exchange (ETDEWEB)

    Rijks, Leonie J.M.; Bos, Jan C. van den; Doremalen, Peter A.P.M. van; Boer, Gerard J.; Bruin, Kora de; Doornbos, Tamme; Vekemans, Jozef A.J.M.; Posthumus, Maarten A.; Janssen, Anton G.M.; Royen, Eric A. van

    1998-05-01

    We have synthesized and evaluated E-11{beta}-nitrato-17{alpha}-iodovinylestradiol (E-NIVE; E-3c) and its {sup 123}I-labelled form, as a new potential radioligand for imaging of estrogen receptor (ER)-positive human breast tumors. E-[{sup 123}I]NIVE was prepared by stereospecific iododestannylation of the E-tri-n-butylstannylvinyl precursor (E-2c), obtained from reaction of 11{beta}-nitrato-estrone (8) with E-tributylstannylvinyllithium. In competitive binding studies, E-NIVE proved to have high binding affinity for both the rat and the human ER (K{sub i} 280-730 pM), without significant binding to human sex hormone binding globulin. Distribution studies in normal and mammary tumor-bearing rats showed specific ER-mediated uptake of E-[{sup 123}I]NIVE in the estrogen target tissues, i.e., uterus, ovaries, pituitary, and hypothalamus, but not in the mammary tumors. Selective retention in these target tissues, including tumor tissue, resulted in significant increases over time for the target tissue-to-muscle uptake ratios, but not for the target tissue-to-fat uptake ratios. The tumor-to-fat uptake ratio even appeared constantly below 1. In the primary estrogen target tissues, E-[{sup 123}I]NIVE displayed high specific ER-mediated uptake and retention, which resulted in moderate target-to-nontarget tissue uptake ratios. In contrast, in tumor tissue, E-[{sup 123}I]NIVE uptake appeared to be rather low and not ER-specific. As a consequence, E-[{sup 123}I]NIVE appears to be a less favorable radioligand for ER imaging in breast cancer than the previously studied stereoisomers of 11{beta}-methoxy-17{alpha}-[{sup 123}I]iodovinylestradiol (E- and Z-[{sup 123}I]MIVE; [{sup 123}I]E- and [{sup 123}I]Z-3b)

  10. CCDC 1436512: Experimental Crystal Structure Determination : 1,9,12,20-tetrakis(Hexyloxy)-7,10,18,21-tetramesitylbenzo[5',10']anthra[2',3':5,6]-s-indaceno[1,2-b]benzo[fg]anthracene-6,17-diol

    KAUST Repository

    Hu, Pan; Lee, Sangsu; Seng, Herng Tun; Aratani, Naoki; Zheng, Bin; Yamada, Hiroko; Huang, Kuo-Wei; Ding, Jun; Kim, Dongho; Wu, Jishan

    2016-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  11. 10,21-Dimethyl-2,7,13,18-tetraphenyl-3,6,14,17-tetraazatricyclo[17.3.1.18,12]tetracosa-1(23,2,6,8(24,9,11,13,17,19,21-decaene-23,24-diol cyclohexane 0.33-solvate

    Directory of Open Access Journals (Sweden)

    Sushil K. Gupta

    2011-10-01

    Full Text Available The title compound, C46H40N4O2·0.33C6H12, was obtained unintentionally as a product of an attempted synthesis of a cadmium(II complex of the [2,6-{PhSe(CH22N=CPh}2C6H2(4-Me(OH] ligand. The full tetraiminodiphenol macrocyclic ligand is generated by the application of an inversion centre. The macrocyclic ligand features strong intramolecular O—H...N hydrogen bonds. The dihedral angles formed between the phenyl ring incorporated within the macrocycle and the peripheral phenyl rings are 82.99 (8 and 88.20 (8°. The cyclohexane solvent molecule lies about a site of overline{3} symmetry. Other solvent within the lattice was disordered and was treated with the SQUEEZE routine [Spek (2009. Acta Cryst. D65, 148–155].

  12. Synthesis, estrogen receptor binding, and tissue distribution of a new iodovinylestradiol derivative (17α,20E)-21-[123I]iodo-11β-nitrato-19-norpregna-1,3,5(10),20-tetraene-3,17 -diol (E-[123I]NIVE)

    International Nuclear Information System (INIS)

    Rijks, Leonie J.M.; Bos, Jan C. van den; Doremalen, Peter A.P.M. van; Boer, Gerard J.; Bruin, Kora de; Doornbos, Tamme; Vekemans, Jozef A.J.M.; Posthumus, Maarten A.; Janssen, Anton G.M.; Royen, Eric A. van

    1998-01-01

    We have synthesized and evaluated E-11β-nitrato-17α-iodovinylestradiol (E-NIVE; E-3c) and its 123 I-labelled form, as a new potential radioligand for imaging of estrogen receptor (ER)-positive human breast tumors. E-[ 123 I]NIVE was prepared by stereospecific iododestannylation of the E-tri-n-butylstannylvinyl precursor (E-2c), obtained from reaction of 11β-nitrato-estrone (8) with E-tributylstannylvinyllithium. In competitive binding studies, E-NIVE proved to have high binding affinity for both the rat and the human ER (K i 280-730 pM), without significant binding to human sex hormone binding globulin. Distribution studies in normal and mammary tumor-bearing rats showed specific ER-mediated uptake of E-[ 123 I]NIVE in the estrogen target tissues, i.e., uterus, ovaries, pituitary, and hypothalamus, but not in the mammary tumors. Selective retention in these target tissues, including tumor tissue, resulted in significant increases over time for the target tissue-to-muscle uptake ratios, but not for the target tissue-to-fat uptake ratios. The tumor-to-fat uptake ratio even appeared constantly below 1. In the primary estrogen target tissues, E-[ 123 I]NIVE displayed high specific ER-mediated uptake and retention, which resulted in moderate target-to-nontarget tissue uptake ratios. In contrast, in tumor tissue, E-[ 123 I]NIVE uptake appeared to be rather low and not ER-specific. As a consequence, E-[ 123 I]NIVE appears to be a less favorable radioligand for ER imaging in breast cancer than the previously studied stereoisomers of 11β-methoxy-17α-[ 123 I]iodovinylestradiol (E- and Z-[ 123 I]MIVE; [ 123 I]E- and [ 123 I]Z-3b).

  13. Development of a Tetrathioether (S4) Bifunctional Chelate System for Rh-105

    Science.gov (United States)

    2013-07-01

    olt s...500 0 500 1000 1500 mV olt s -500 0 500 1000 1500 (B) Free Rhodium Chloride Minutes 0 2 4 6 8 10 12 mV olt s 0 2000 4000 mV olt s 0 2000 4000 (C) Rh-S4...Diol prepared in water Minutes 0 2 4 6 8 10 12 mV olts 0 2000 4000 mV olts 0 2000 4000 (D) 105 Rh-S4Diol with cold [Rh-S4(OH)2-Diol] +

  14. Carbohydrate-based Polyurethanes and Polyamides: Synthesis, Characterization and Stereocomplex Formation

    OpenAIRE

    Marín Bernabé, Romina

    2009-01-01

    Esta tesis doctoral está dirigida al desarrollo de poliuretanos a partir de dioles derivados de carbohidratos. Los poliuretanos son polímeros muy versátiles que pueden ser usados en una amplia variedad de aplicaciones que van desde espumas de relleno a artículos técnicos. Actualmente, existe un interés creciente por parte de la industria del poliuretano en la incorporación de productos procedentes de fuentes renovables. Dioles derivados de grasas naturales y aceites así como otros dioles d...

  15. Kinetics and mechanism of the oxidation of some vicinal and non ...

    Indian Academy of Sciences (India)

    Unknown

    2.1 Materials. The diols and monoethers used were commercial products (BDH or Fluka) and were ..... charge separation takes place in the transition state of the reaction. ... The following mechanism (scheme 1) accounts for the observed data.

  16. Three new triterpene esters from pumpkin (Cucurbita maxima) seeds.

    Science.gov (United States)

    Kikuchi, Takashi; Ueda, Shinsuke; Kanazawa, Jokaku; Naoe, Hiroki; Yamada, Takeshi; Tanaka, Reiko

    2014-04-16

    Three new multiflorane-type triterpene esters, i.e. 7α-hydroxymultiflor-8-ene-3α,29-diol 3-acetate-29-benzoate (1), 7α-methoxymultiflor-8-ene-3α,29-diol 3,29-dibenzoate (2), and 7β-methoxymultiflor-8-ene-3α,29-diol 3,29-dibenzoate (3), were isolated from seeds of Cucurbita maxima, along with the known compound, multiflora-7,9(11)-diene-3α,29-diol 3,29-dibenzoate (4). Compound 1 exhibited melanogenesis inhibitory activities comparable with those of arbutin. In cytotoxicity assays, compounds 1 and 3 exhibited weak cytotoxicity, with IC50 values of 34.5-93.7 μM against HL-60 and P388 cells.

  17. Three New Triterpene Esters from Pumpkin (Cucurbita maxima Seeds

    Directory of Open Access Journals (Sweden)

    Takashi Kikuchi

    2014-04-01

    Full Text Available Three new multiflorane-type triterpene esters, i.e. 7α-hydroxymultiflor-8-ene-3α,29-diol 3-acetate-29-benzoate (1, 7α-methoxymultiflor-8-ene-3α,29-diol 3,29-dibenzoate (2, and 7β-methoxymultiflor-8-ene-3α,29-diol 3,29-dibenzoate (3, were isolated from seeds of Cucurbita maxima, along with the known compound, multiflora-7,9(11-diene-3α,29-diol 3,29-dibenzoate (4. Compound 1 exhibited melanogenesis inhibitory activities comparable with those of arbutin. In cytotoxicity assays, compounds 1 and 3 exhibited weak cytotoxicity, with IC50 values of 34.5–93.7 μM against HL-60 and P388 cells.

  18. Comparative Structural Analysis of ERa and ERb Bound to Selective Estrogen Agonists and Antagonists

    National Research Council Canada - National Science Library

    Greene, Geoffrey

    2001-01-01

    ...) complexed with receptor-selective estrogens and antiestrogens (SERMs) The crystallographic structures of ERalpha and ERbeta ligand binding domains complexed with cis-R,R-diethyl-tetrahydrochrysene-2,8-diol (R,R-THC...

  19. Comparative Structural Analysis of ERa and ERb Bound to Selective Estrogen Agonists and Antagonists

    National Research Council Canada - National Science Library

    Greene, Geoggrey

    2000-01-01

    ...) complexed with receptor-selective estrogens and antiestrogens (SERMs). The crystallographic structures of ERalpha and ERbeta ligand binding domains complexed with cis- R,R-diethyl-tetrahydrochrysene-2, 8 -diol (R,R-THC...

  20. Using GC-combustion isotope ratio mass spectrometry for confirming steroid administration from urinary metabolites in humans and animals

    International Nuclear Information System (INIS)

    Phillips, A.; Churchman, D.; Davis, S.

    2000-01-01

    Gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) was used to study the incorporation of exogenous testosterone enanthate into excreted urinary 5α- and 5β-androstane-3α, 17β-diols

  1. [Synthesis and characterization of polylactide-based thermosetting polyurethanes with shape memory properties].

    Science.gov (United States)

    Shi, Shuo; Gu, Lin; Yang, Yihu; Yu, Haibin; Chen, Rui; Xiao, Xianglian; Qiu, Jun

    2016-06-25

    A series of bio-based thermosetting polyurethanes (Bio-PUs) were synthesized by the crosslinking reaction of polylactide and its copolymers diols with hexamethylene diisocyanate (HDI) trimer. The obtained Bio-PUs were characterized by Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), Thermal Gravimetric Analysis (TGA), universal tensile testing machine and cytotoxicity test. Results indicate that the PLA copolymer (P(LA-co-CL)) diols reduced the glass transition temperature (Tg) of Bio-PUs and improved their thermal stability, compared with PLA diols. The Bio-PUs synthesized from P (LA-co-CL) diols exhibit better mechanical performance and shape memory properties. Especially, Young modulus and elongation at break of the obtained Bio-PUs were 277.7 MPa and 230% respectively; the shape recovery time of the obtained Bio-PUs at body temperature was only 93 s. Furthermore, alamar blue assay results showed that the obtained Bio-PUs had no cell toxicity.

  2. (S)-Garner aldehyde derived Baylis-Hillman adduct: A potential ...

    Indian Academy of Sciences (India)

    phytosphingosine analogue intermediate diol which on acid hydrolysis resulted in the formation of the target molecule in good ... transduction.11 The basic structure of a sphingolipid is ... sulphate) and a fatty acyl chain linked to amino group.

  3. The mechanism of the modified Ullmann reaction

    NARCIS (Netherlands)

    Sperotto, Elena; Klink, Gerard P.M. van; Koten, Gerard van; Vries, Johannes G. de

    2010-01-01

    The copper-mediated aromatic nucleophilic substitution reactions developed by Fritz Ullmann and Irma Goldberg required stoichiometric amounts of copper and very high reaction temperatures. Recently, it was found that addition of relatively cheap ligands (diamines, aminoalcohols, diketones, diols)

  4. Synthesis and crystallographic analysis of meso-2,3-difluoro-1,4-butanediol and meso-1,4-dibenzyloxy-2,3-difluorobutane

    Directory of Open Access Journals (Sweden)

    Bruno Linclau

    2010-06-01

    Full Text Available A large-scale synthesis of meso-2,3-difluoro-1,4-butanediol in 5 steps from (Z-but-2-enediol is described. Crystallographic analysis of the diol and the corresponding benzyl ether reveals an anti conformation of the vicinal difluoride moiety. Monosilylation of the diol is high-yielding but all attempts to achieve chain extension through addition of alkyl Grignard and acetylide nucleophiles failed.

  5. Photonic crystal borax competitive binding carbohydrate sensing motif†

    Science.gov (United States)

    Cui, Qingzhou; Muscatello, Michelle M. Ward; Asher, Sanford A.

    2009-01-01

    We developed a photonic crystal sensing method for diol containing species such as carbohydrates based on a poly(vinyl alcohol) (PVA) hydrogel containing an embedded crystalline colloidal array (CCA). The polymerized CCA (PCCA) diffracts visible light. We show that in the presence of borax the diffraction wavelength shifts as the concentration of glucose changes. The diffraction shifts result from the competitive binding of glucose to borate, which reduces the concentration of borate bound to the PVA diols. PMID:19381378

  6. Photonic crystal borax competitive binding carbohydrate sensing motif.

    Science.gov (United States)

    Cui, Qingzhou; Ward Muscatello, Michelle M; Asher, Sanford A

    2009-05-01

    We developed a photonic crystal sensing method for diol containing species such as carbohydrates based on a poly(vinyl alcohol) (PVA) hydrogel containing an embedded crystalline colloidal array (CCA). The polymerized CCA (PCCA) diffracts visible light. We show that in the presence of borax the diffraction wavelength shifts as the concentration of glucose changes. The diffraction shifts result from the competitive binding of glucose to borate, which reduces the concentration of borate bound to the PVA diols.

  7. Bacterial cells with improved tolerance to polyols

    DEFF Research Database (Denmark)

    2017-01-01

    The present invention relates to bacterial cells genetically modified to improve their tolerance to certain commodity chemicals, such as diols and other polyols, and to methods of preparing and using such bacterial cells for production of polyols and other compounds.......The present invention relates to bacterial cells genetically modified to improve their tolerance to certain commodity chemicals, such as diols and other polyols, and to methods of preparing and using such bacterial cells for production of polyols and other compounds....

  8. Testicular function in a birth cohort of young men

    DEFF Research Database (Denmark)

    Hart, R J; Doherty, D A; McLachlan, R I

    2015-01-01

    , testosterone, dihydrotestosterone (DHT), dehydroepiandrosterone (DHEA), estradiol, estrone and the primary metabolites of DHT: 5α-androstane-3α,17β-diol (3α-diol) and 5-α androstane-3-β-17-beta-diol (3β-diol). Serum steroids were measured by liquid chromatography, mass spectrometry and LH, FSH and inhibin B...... or circulating reproductive hormones. BMI had a significantly negative correlation with semen volume (r = -0.12, P = 0.048), sperm output (r = -0.13, P = 0.02), serum LH (r = -0.16, P = 0.002), inhibin B (r = -0.16, P DHT (r = -0.22, P ... not differ from those who did (n = 423) with regard to age, weight, BMI, smoking or circulating reproductive hormones (LH, FSH, inhibin B, T, DHT, E2, E1, DHEA, 3α-diol, 3β-diol), but were significantly shorter (178 versus 180 cm, P = 0.008) and had lower alcohol consumption (P = 0.019) than those who did...

  9. 3α-androstanediol, but not testosterone, attenuates age-related decrements in cognitive, anxiety, and depressive behavior of male rats

    Directory of Open Access Journals (Sweden)

    Cheryl A Frye

    2010-04-01

    Full Text Available Some hippocampally-influenced affective and/or cognitive processes decline with aging. The role of androgens in this process is of interest. Testosterone (T is aromatized to estrogen, and reduced to dihydrotestosterone (DHT, which is converted to 5α-androstane, 3α, 17α-diol (3α-diol. To determine the extent to which some age-related decline in hippocampally-influenced behaviors may be due to androgens, we examined the effects of variation in androgen levels due to age, gonadectomy, and androgen replacement on cognitive (inhibitory avoidance, Morris water maze and affective (defensive freezing, forced swim behavior among young (4-months, middle-aged (13-months, and aged (24-months male rats. Plasma and hippocampal levels of androgens were determined. In experiment 1, comparisons were made between 4-, 13-, and 24-month old rats that were intact or gonadectomized (GDX and administered a T-filled or empty silastic capsule. There was age-related decline in performance of the inhibitory avoidance, water maze, defensive freezing, and forced swim tasks, and hippocampal 3α-diol levels. Chronic, long-term (1-4 weeks T-replacement reversed the effects of GDX in 4- and 13-month old, but not 24-month old, rats in the inhibitory avoidance task. Experiments 2 and 3 assessed whether acute subcutaneous T or 3α-diol, respectively, could reverse age-associated decline in performance. 3α-diol, but not T, compared to vehicle, improved performance in the inhibitory avoidance, water maze, forced swim, and defensive freezing tasks, irrespective of age. Thus, age is associated with a decrease in 3α-diol production and 3α-diol administration reinstates cognitive and affective performance of aged male rats.

  10. Novel metallomesogenic polyurethanes: Synthesis, characterization and properties

    International Nuclear Information System (INIS)

    Senthilkumar, Natarajan; Narasimhaswamy, Tanneru; Kim, Il-Jin

    2012-01-01

    A series of tetradentate Schiff base metallomesogenic diols were synthesized from two simple dihydroxy benzenes. The metallomesogenic diol was constructed from three ring containing mesogen linked through ester and azomethine with terminal hydroxy group. This upon complexation with copper(II) formed metallomesogenic diol with varying terminal chain length. A series of metallomesogenic polyurethanes were synthesized using these metallomesogenic diols as chain extenders for the prepolymers based on polytetramethylene glycol (PTMG) of varying molecular weight (M n = 650, 2000) and 2,4-toluene diisocyanate (TDI), or 4,4′-methylene bis(phenyl isocyanate) (MDI). The molar ratio of metallomesogenic diol and PTMG were varied in the polyurethane to find their role in liquid crystalline and mechanical properties. Extensive characterization of all metallomesogenic compounds and intermediates were carried out by FT-IR, 1 H and 13 C NMR, EPR, VSM, Mass (EI and FAB) and UV–visible spectroscopy. Hot stage polarizing microscope and differential scanning calorimetry were used to ensure the phase characteristics such as nature of phase, melting and clearing temperatures and phase range. The appearance of enantiotropic smectic A phases indicated high molecular polarizability of the core due to the metal ion. - Highlights: ► Design and synthesis of metallomesogenic diols. ► Metallomesogenic polyurethanes were prepared using these diols as chain extenders. ► Liquid crystalline and mechanical properties were studied. ► A square pyramidal structure for the copper(II) complexes have been proposed. ► Polyurethanes exhibited enantiotropic smectic A phases.

  11. Drug testing data from the 2007 Pan American Games: delta13C values of urinary androsterone, etiocholanolone and androstanediols determined by GC/C/IRMS.

    Science.gov (United States)

    Aguilera, Rodrigo; Chapman, Thomas E; Pereira, Henrique; Oliveira, Giselle C; Illanes, Renata P; Fernandes, Telma F; Azevedo, Débora A; Neto, Francisco Aquino

    2009-07-01

    The main purpose of this article is to show the application of the CG/C/IRMS in real time during competition in the steroid confirmation analysis. For this reason, this paper summarizes the results obtained from the doping control analysis during the period of the 2007 Pan American Games held in Rio de Janeiro, Brazil. Approximately 5600 athletes from 42 different countries competed in the games. Testing was performed in accordance to World Anti-Doping Agency (WADA) technical note for prohibited substances. This paper reports data where abnormal urinary steroid profiles, have been found with the screening procedures. One 8 mL urine sample was used for the analysis of five steroid metabolites with two separate analyses by gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS). Urine samples were submitted to GC/C/IRMS for confirmation analysis to determine the (13)C/(12)C ratio of selected steroids. Fifty-seven urine samples were analyzed by GC/C/IRMS and the delta(13)C values ( per thousand) of androsterone, etiocholanolone, 5beta-androstane-3alpha, 17beta-diol (5beta-diol), 5alpha-androstane-3alpha, 17beta-diol (5alpha-diol) and 5beta-pregnane-3alpha, 20alpha-diol (5beta-pdiol), the endogenous reference compound are presented. One urine sample with a testosterone/epitestosterone (T/E) ratio of 4.7 was confirmed to be positive of doping by GC/C/IRMS analysis. The delta values of 5beta-diol and 5alpha-diol were 3.8 and 10.8, respectively, compared to the endogenous reference compound 5beta-pdiol, which exceeded the WADA limit of 3 per thousand. The results obtained by CG/C/IRMS confirmation analyses, in suspicious samples, were conclusive in deciding whether or not a doping steroid violation had occurred.

  12. Neurosteroid 3α-androstanediol efficiently counteracts paclitaxel-induced peripheral neuropathy and painful symptoms.

    Directory of Open Access Journals (Sweden)

    Laurence Meyer

    Full Text Available Painful peripheral neuropathy belongs to major side-effects limiting cancer chemotherapy. Paclitaxel, widely used to treat several cancers, induces neurological symptoms including burning pain, allodynia, hyperalgesia and numbness. Therefore, identification of drugs that may effectively counteract paclitaxel-induced neuropathic symptoms is crucial. Here, we combined histopathological, neurochemical, behavioral and electrophysiological methods to investigate the natural neurosteroid 3α-androstanediol (3α-DIOL ability to counteract paclitaxel-evoked peripheral nerve tissue damages and neurological symptoms. Prophylactic or corrective 3α-DIOL treatment (4 mg/kg/2 days prevented or suppressed PAC-evoked heat-thermal hyperalgesia, cold-allodynia and mechanical allodynia/hyperalgesia, by reversing to normal, decreased thermal and mechanical pain thresholds of PAC-treated rats. Electrophysiological studies demonstrated that 3α-DIOL restored control values of nerve conduction velocity and action potential peak amplitude significantly altered by PAC-treatment. 3α-DIOL also repaired PAC-induced nerve damages by restoring normal neurofilament-200 level in peripheral axons and control amount of 2',3'-cyclic-nucleotide-3'-phosphodiesterase in myelin sheaths. Decreased density of intraepidermal nerve fibers evoked by PAC-therapy was also counteracted by 3α-DIOL treatment. More importantly, 3α-DIOL beneficial effects were not sedation-dependent but resulted from its neuroprotective ability, nerve tissue repairing capacity and long-term analgesic action. Altogether, our results showing that 3α-DIOL efficiently counteracted PAC-evoked painful symptoms, also offer interesting possibilities to develop neurosteroid-based strategies against chemotherapy-induced peripheral neuropathy. This article shows that the prophylactic or corrective treatment with 3α-androstanediol prevents or suppresses PAC-evoked painful symptoms and peripheral nerve dysfunctions in

  13. Diastereoselective and enantioselective reduction of tetralin-1,4-dione

    Directory of Open Access Journals (Sweden)

    2008-10-01

    Full Text Available BackgroundThe chemistry of tetralin-1,4-dione, the stable tautomer of 1,4-dihydroxynaphthalene, has not been explored previously. It is readily accessible and offers interesting opportunities for synthesis.ResultsThe title reactions were explored. L-Selectride reduced the diketone to give preferentially the cis-diol (d.r. 84 : 16. Red-Al gave preferentially the trans-diol (d.r. 13 : 87. NaBH4, LiAlH4, and BH3 gave lower diastereoselectivities (yields: 76–98%. Fractional crystallization allowed isolation of the cis-diol and the trans-diol (55% and 66% yield, respectively. Borane was used to cleanly give the mono-reduction product. Highly enantioselective CBS reductions afforded the trans-diol (72% yield, 99% ee and the mono-reduction product (81%, 95% ee.ConclusionDiastereoselective and enantioselective reductions of the unexplored tetralin-1,4-dione provides a very convenient entry into a number of synthetically highly attractive 1,4-tetralindiols and 4-hydroxy-1-tetralone.

  14. Diastereoselective and enantioselective reduction of tetralin-1,4-dione.

    Science.gov (United States)

    Kündig, E Peter; Enriquez-Garcia, Alvaro

    2008-01-01

    The chemistry of tetralin-1,4-dione, the stable tautomer of 1,4-dihydroxynaphthalene, has not been explored previously. It is readily accessible and offers interesting opportunities for synthesis. The title reactions were explored. L-Selectride reduced the diketone to give preferentially the cis-diol (d.r. 84 : 16). Red-Al gave preferentially the trans-diol (d.r. 13 : 87). NaBH(4), LiAlH(4), and BH(3) gave lower diastereoselectivities (yields: 76-98%). Fractional crystallization allowed isolation of the cis-diol and the trans-diol (55% and 66% yield, respectively). Borane was used to cleanly give the mono-reduction product. Highly enantioselective CBS reductions afforded the trans-diol (72% yield, 99% ee) and the mono-reduction product (81%, 95% ee). Diastereoselective and enantioselective reductions of the unexplored tetralin-1,4-dione provides a very convenient entry into a number of synthetically highly attractive 1,4-tetralindiols and 4-hydroxy-1-tetralone.

  15. The synthesis and pyrolysis of polycyclic organic sulphites

    International Nuclear Information System (INIS)

    Venter, H.J.

    1988-01-01

    The syntheses and thermolyses of model sulphite substrates were investigated: Lithium aluminium hidride reductions via the formation of a cyclic transition state lead to the formation of an endo-endo-diol as the main product. In contrast with the above, sodium borohidride reductions proceded via the formation of an acyclic transition state, which gave rise to different end products. The influence of specific reaction mechanisms on the product distribution of hidride reductions is discussed. The pinacoles required for the syntheses of certain substrates were obtained by means of the Clemmensen reductions. An unusual alcohol was formed during one of Clemmensen reductions. A mechanisms for ring cleavage and pinacole formation is presented, while a modified mechanism is proposed for the Clemmensen reduction of ketones. Treatment of some of the pinacoles with thionyl chloride lead to the formation of specific sulphites. A cyclic sulphite was derived from a diol obtained via a lithium aluminium hidride reduction reaction. In contrast a specific diketone was converted to a specific hemiketal when treated with zinc and acetic acid. Attempts to convert the diketone to the corresponding diol were unsuccessful. The pyrolytic behaviour of some sulphites as well as some of the diols were investigated. The pyrolysis of γ-diols and the corresponding sulphites proceded similarly. Various structures were derived from extensive comparative 1 H- and 13 C- studies

  16. Synthesis and Characterization of Mono- and Bicycle Heterocyclic Derivatives Containing 1, 2,4-Triazole, 1,3,4-Thiadiazine and 1,3-Thiazole Rings

    Directory of Open Access Journals (Sweden)

    Navabeh Nami

    2012-01-01

    Full Text Available Reaction of tartaric acid with thiocarbohydrazide (2 and thiosemicarbazide (6 afforded 1,2-bis(4-amino-5-mercapto-4H-1,2,4-triazol-3-yl-ethane-1,2-diol (3 and 1,2-bis(5-mercapto-4H-1,2,4-triazol-3-yl-ethane-1,2-diol (7. Reaction of compounds 3 and 7 with DMAD (dimethylacety lendi carboxylate and DEAD (diethylacetylendicarboxylate gave 1,2-bis(7-[(z-methoxycarbonylmethylen]-5,6-dihydro-5H-6-one-[1,2,4] riazolo[3,4-b] [1,3,4] thiadiazin-3-yl-ethan-1,2-diol (4, 1,2-bis(7-[(z-ethoxycarbonylmethylen] -5,6-dihydro -5H-6-one-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazin-3-yl-ethan-1,2- diol (5 and 1,2-bis(6-[(z-methoxycarbonylmethylen]-5-oxo-[1,3]thiazolo[2,3-c] [1,2,4]triazol-3-yl-ethan-1,2-diol (8 in good yields.

  17. Inhibition of dihydrotestosterone synthesis in prostate cancer by combined frontdoor and backdoor pathway blockade

    Science.gov (United States)

    Fiandalo, Michael V.; Stocking, John J.; Pop, Elena A.; Wilton, John H.; Mantione, Krystin M.; Li, Yun; Attwood, Kristopher M.; Azabdaftari, Gissou; Wu, Yue; Watt, David S.; Wilson, Elizabeth M.; Mohler, James L.

    2018-01-01

    Androgen deprivation therapy (ADT) is palliative and prostate cancer (CaP) recurs as lethal castration-recurrent/resistant CaP (CRPC). One mechanism that provides CaP resistance to ADT is primary backdoor androgen metabolism, which uses up to four 3α-oxidoreductases to convert 5α-androstane-3α,17β-diol (DIOL) to dihydrotestosterone (DHT). The goal was to determine whether inhibition of 3α-oxidoreductase activity decreased conversion of DIOL to DHT. Protein sequence analysis showed that the four 3α-oxidoreductases have identical catalytic amino acid residues. Mass spectrometry data showed combined treatment using catalytically inactive 3α-oxidoreductase mutants and the 5α-reductase inhibitor, dutasteride, decreased DHT levels in CaP cells better than dutasteride alone. Combined blockade of frontdoor and backdoor pathways of DHT synthesis provides a therapeutic strategy to inhibit CRPC development and growth. PMID:29541409

  18. Probing the General Time Scale Question of Boronic Acid Binding with Sugars in Aqueous Solution at Physiological pH

    Science.gov (United States)

    Ni, Nanting; Laughlin, Sarah; Wang, Yingji; Feng, You; Zheng, Yujun

    2012-01-01

    The boronic acid group is widely used in chemosensor design due to its ability to reversibly bind diol-containing compounds. The thermodynamic properties of the boronic acid-diol binding process have been investigated extensively. However, there are few studies of the kinetic properties of such binding processes. In this report, stopped-flow method was used for the first time to study the kinetic properties of the binding between three model arylboronic acids, 4-, 5-, and 8-isoquinolinylboronic acids, and various sugars. With all the boronic acid-diol pair sexamined, reactions were complete within seconds. The kon values with various sugars follow the order of D-fructose >D-tagatose>D-mannose >D-glucose. This trend tracks the thermodynamic binding affinities for these sugars and demonstrates that the “on” rate is the key factor determining the binding constant. PMID:22464680

  19. Regio- and Enantioselective Sequential Dehalogenation of rac-1,3-Dibromobutane by Haloalkane Dehalogenase LinB.

    Science.gov (United States)

    Gross, Johannes; Prokop, Zbyněk; Janssen, Dick; Faber, Kurt; Hall, Mélanie

    2016-08-03

    The hydrolytic dehalogenation of rac-1,3-dibromobutane catalyzed by the haloalkane dehalogenase LinB from Sphingobium japonicum UT26 proceeds in a sequential fashion: initial formation of intermediate haloalcohols followed by a second hydrolytic step to produce the final diol. Detailed investigation of the course of the reaction revealed favored nucleophilic displacement of the sec-halogen in the first hydrolytic event with pronounced R enantioselectivity. The second hydrolysis step proceeded with a regioselectivity switch at the primary position, with preference for the S enantiomer. Because of complex competition between all eight possible reactions, intermediate haloalcohols formed with moderate to good ee ((S)-4-bromobutan-2-ol: up to 87 %). Similarly, (S)-butane-1,3-diol was formed at a maximum ee of 35 % before full hydrolysis furnished the racemic diol product. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Divergent Synthesis of Solanidine and 22-epi-Solanidine.

    Science.gov (United States)

    Hou, Ling-Li; Shi, Yong; Zhang, Zhi-Dan; Wu, Jing-Jing; Yang, Qing-Xiong; Tian, Wei-Sheng

    2017-07-21

    A divergent synthesis of solanidine and 22-epi-solanidine, two 25S natural steroidal alkaloids, from 25R-configured diosgenin acetate, is described. Initially, solanidine was synthesized through a series of transformations including a cascade ring-switching process of furostan-26-acid, an epimerization of C25 controlled by the conformation of six-membered lactone ring, an intramolecular Schmidt reaction, and an imine reduction/intramolecular aminolysis process. To address the epimerization issue during Schmidt reaction, an improved synthesis was developed, which also led to a synthesis of 22-epi-solanidine. In this synthesis, selective transformation of azido lactone to azido diol and amino diol was realized through a reduction relay tactic. The azido diol was transformed to solanidine via an intramolecular Schmidt reaction/N-alkylation/reduction process and to 22-epi-solanidine via an intramolecular double N-alkylation process.

  1. Thermal stability of segmented polyurethane elastomers reinforced by clay particles

    Directory of Open Access Journals (Sweden)

    Pavličević Jelena

    2009-01-01

    Full Text Available The aim of this work was to determine the influence of clay nanoparticles on thermal properties of segmented polyurethanes based on hexamethylene- diisocyanate, aliphatic polycarbonate diol and 1,4-butanediol as chain extender. The organically modified particles of montmorillonite and bentonite were used as reinforcing fillers. The structure of elastomeric materials was varied either by diol type or chain extender content. The ratio of OH groups from diol and chain extender (R was either 1 or 10. Thermal properties of prepared materials were determined using modulated differential scanning calorimetry (MDSC. Thermal stability of obtained elastomers has been studied by simultaneously thermogravimetry coupled with DSC. The glass transition temperature, Tg, of soft segments for all investigated samples was about -33°C. On the basis of DTG results, it was concluded that obtained materials were very stable up to 300°C.

  2. Chemical Constituents from Bombacopsis glabra (Pasq. A. Robyns: Complete 1H and 13C NMR Assignments and X Ray Structure of 5-Hydroxy-3,6,7,8,4'-pentamethoxyflavone

    Directory of Open Access Journals (Sweden)

    Paula Vanderlúcia F.

    2002-01-01

    Full Text Available The flavone 5-hydroxy-3,6,7,8,4'-pentamethoxyflavone (1 and the triterpenes lupenone, 9,19-cyclolanost-23-ene-3beta,25-diol (2, (24R-9,19-cyclolanost-25-ene-3beta,24-diol (3 and (24S-9,19-cyclolanost-25-ene-3beta,24-diol (4 were isolated from the hexane extract of the stem bark of Bombacopsis glabra (Bombacaceae. The structures were determined by 13C and ¹H NMR (1D and 2D and mass spectrometry, and by comparison with literature data for triterpenes. The structure of the flavone 1 was unambiguously confirmed by a X-ray diffraction study. The five substances were isolated for the first time from Bombacaceae species.

  3. Novel metabolic pathways for linoleic and arachidonic acid metabolism.

    Science.gov (United States)

    Moghaddam, M; Motoba, K; Borhan, B; Pinot, F; Hammock, B D

    1996-08-13

    Mouse liver microsomes oxidized linoleic acid to form 9,10- or 12,13-epoxyoctadecenoate. These monoepoxides were subsequently hydrolyzed to their corresponding diols in the absence of the microsomal epoxide hydrolase inhibitor, 1,2-epoxy-3,3,3-trichloropropane. Furthermore, both 9,10- and 12,13-epoxyoctadecenoates were oxidized to diepoxyoctadecanoate at apparently identical rates by mouse liver microsomal P-450 epoxidation. Both epoxyoctadecanoates and diepoxyoctadecanoates were converted to tetrahydrofuran-diols by microsomes. Tetrahydroxides of linoleate were produced as minor metabolites. Arachidonic acid was metabolized to epoxyeicosatrienoates, dihydroxyeicosatrienoates, and monohydroxyeicosatetraenoates by the microsomes. Microsomes prepared from clofibrate (but not phenobarbital) -treated mice exhibited much higher production rates for epoxyeicosatrienoates and vic-dihydroxyeicosatrienoates. This indicated an induction of P-450 epoxygenase(s) and microsomal epoxide hydrolase in mice by clofibrate and not by phenobarbital. Incubation of synthetic epoxyeicosatrienoates with microsomes led to the production of diepoxyeicosadienoates. Among chemically generated diepoxyeicosadienoate isomers, three of them possessing adjacent diepoxides were hydrolyzed to their diol epoxides which cyclized to the corresponding tetrahydrofuran-diols by microsomes as well as soluble epoxide hydrolase at a much higher rate. Larger cyclic products from non-adjacent diepoxides were not observed. The results of our in vitro experiments suggest that linoleic and arachidonic acid can be metabolized to their tetrahydrofuran-diols by two consecutive microsomal cytochrome P-450 epoxidations followed by microsomal or soluble epoxide hydrolase catalyzed hydrolysis of the epoxides. Incubation experiments with the S-9 fractions indicate that the soluble epoxide hydrolase is more important in this conversion. This manuscript is the first report of techniques for the separation and

  4. Synthesis of waterborne polyurethane containing alkoxysilane side groups and the properties of the hybrid coating films

    Energy Technology Data Exchange (ETDEWEB)

    Li, Qi; Guo, Longhai [State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029 (China); Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing University of Chemical Technology, Beijing 100029 (China); Qiu, Teng, E-mail: qiuteng@mail.buct.edu.cn [State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029 (China); Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing University of Chemical Technology, Beijing 100029 (China); Xiao, Weidong; Du, Dianxing [State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029 (China); Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing University of Chemical Technology, Beijing 100029 (China); Li, Xiaoyu, E-mail: lixy@mail.buct.edu.cn [State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029 (China); Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing University of Chemical Technology, Beijing 100029 (China)

    2016-07-30

    Highlights: • A diol with side-chain trimethoxysilane (DEA-Si) was synthesized using 3-(methacryloxypropyl)trimethoxysilane (MAPTS) and diethanolamine (DEA). • The crosslinking structure could in situ formed within the WPU matrix through sol-gel process. • The Si tends to shift to the polymer-air interface due to the flexible long alkyl-ester side chain. • The incorporation of DEA-Si enhanced mechanical and surface hydrophobic properties of WPU films. - Abstract: A series of waterborne polyurethane (WPU) containing alkoxysilane side groups were synthesized by using the dihydroxy functionalized alkoxysilane. The diol with trimethoxysilane groups at the side chains was synthesized via Michael addition between 3-(methacryloxypropyl)trimethoxysilane (MAPTS) and diethanolamine (DEA). The silane diol was applied as the chain extender for the NCO-endcapped prepolymer of isophorone diisocyanate, polycarbonate diol, 2,2-bis(hydroxymethyl) butyric acid and 1,4-butanediol. The products with the silane content varied from 1.2 to 16.5 wt% were dispersed in water after neutralization. The effect of the silane diol on the particle size and morphology of the WPU dispersion was studied by dynamic light scattering (DLS) and transmission electron microscopy (TEM), respectively. X-ray photoelectron spectroscopy (XPS) characterization was carried out on the coating film of the WPU, revealing that the long flexible side chain is favorable for the silane components to emigrate toward the film surface and crosslink during the film formation process. As a result, both the surface contact angle to water and water adsorption of the WPU coating films increased with the silane content. Furthermore, the mechanical properties including the modulus and tensile strength of the films were also improved by the incorporation of silane diol.

  5. Lipids of the Tail Gland, Body and Muzzle Fur of the Red Fox, Vulpes vulpes.

    Science.gov (United States)

    McLean, Stuart; Davies, Noel W; Nichols, David S

    2017-07-01

    The tail gland of the red fox (Vulpes vulpes) secretes lipids containing volatile terpenes used in social communication. We have analysed lipids extracted from fur of the tail gland, body (flanks) and muzzle of foxes. GC-MS showed a novel group of iso-valerate and tiglate monoesters of alkane-1,2-diols (C18:0-22:0). There was also a larger group of Type II diesters in which a second, longer chain, fatty acid (FA) was attached to the free alcohol group. LC-MS showed the full range of diol diesters, mostly C36:0-50:0, with smaller amounts of the corresponding mono-unsaturated tiglate esters. An additional group of diesters with higher MW (C49:0-62:0) containing two long-chain FA was present in the lipids of body and muzzle fur. After saponification and GC-MS, 98 fatty acids were characterized as their methyl esters. Apart from the C5 FA, most were saturated n-, iso-, anteiso- or other methyl-branched FA (C12:0-28:0) whose structures were determined by a combination of their mass spectra and Kovats retention indices. Several FA have not previously been found in nature or in vertebrates. Thirty-four alkane-1,2-diols were found as their TMS derivatives, mostly n-, iso- or anteiso-isomers of C16:0-25:0. The tail gland had the greatest amount of wax esters, from a greater variety of FA and diols, but lacked the esters with two long-chain FA. These findings show that fox skin lipids comprise mono- and di-esters of alkane-1,2-diols, and exhibit enormous complexity due to the diversity of their constituent FA, diols and the many possible isomers of their esters.

  6. Photoinduced azidohydroperoxidation of myrtenyl hydroperoxide with semiconductor particles and lucigenin as PET-catalysts.

    Science.gov (United States)

    Griesbeck, Axel G; Reckenthäler, Melissa; Uhlig, Johannes

    2010-06-01

    The allylic hydroperoxide 2 (myrtenyl hydroperoxide), available from singlet oxygen photooxygenation of beta-pinene (1), is converted into the azido bis-hydroperoxide 3 by an electron-transfer induced azidyl radical formation and trapping of the initial tertiary carbon radical by triplet oxygen. The azido bis-hydroperoxide 3 is reduced to the azido 1,2-diol 4 or the amino diol 5, respectively. Beside classical fluorescent PET sensitizers such as rhodamines, also nanosized semiconductor particles as well as lucigenin were applied as catalysts. The electron transfer rate of azide oxidation was determined for lucigenin by fluorescence quenching analysis.

  7. Detection of DNA damage in fish Oreochromis mossambicus induced by co-exposure to phenanthrene and nitrite by ESI-MS/MS

    Digital Repository Service at National Institute of Oceanography (India)

    Wahidullah, S.; Rajamanickam, Y.R.

    also be formed in situ from PAH and ⋅ NO 3 (nitrate) radical in presence of a ⋅ OH (hydroxyl) radical (Fan et al. 1996; Feilberg et al. 1999). In the marine environment, they are formed within fish when co-exposed to the anthropogenic organic pollutants... to the identification of adduct as NPDE-N 2 -dG adduct. Inci- dentally, the free metabolite, i.e. nitrophenanthrene diol epoxide was reported earlier in the bile (Shailaja et al. 2006). 3.4.2 DNN-acetylamino PDE-N 7 dG (Dinitro N-acetylaminophenanthrene diol epoxide-N 7...

  8. Optimisation of the biocatalytic resolution of styrene oxide by whole cells of Rhodotorula glutinis

    CSIR Research Space (South Africa)

    Yeates, CA

    2007-01-01

    Full Text Available capillary column (chiral analysis) using 2 as carrier gas. Racemic SO and (R)-1-phenyl-1,2-ethane diol were obtained m Aldrich, while (S)-SO was obtained from Fluka. Chiral GC analysis of he isolated products after biohydrolysis were done as follows: SO..., yields: % yield of (S)-SO, yieldp: % yield R)-1-phenyl-1,2-ethane diol. To determine the optimal temperature for the highest enan- ivity, time-course reactions were performed at various s with an initial epoxide concentration of 30 mM. he results...

  9. Nanocrystalline hydroxyapatite ceramics prepared by hydrolysis in polyol medium

    Science.gov (United States)

    Mechay, Abderrahmen; Feki, Hafed E. L.; Schoenstein, Fréderic; Jouini, Noureddine

    2012-07-01

    This Letter describes a new approach for the synthesis of hydroxyapatite nanoparticles, which involves precipitation and hydrolysis reactions conducted in polyol medium. In fact, ammonium-hydrogen phosphate and calcium nitrate were dissolved in polyol, and then heated at the boiling point of the polyol (ethane1, 2diol or propane1, 2diol). Besides, the phase and composition of the polycrystalline were studied by TGA/DTA, FT-IR, TEM and XRD techniques. The nanoparticles thus obtained present interesting morphological characters varying from needle to very thin platelet. Moreover, the hydroxyapatite prepared in ployol shows higher cristallinity in comparison with that obtained by other 'chimie douce' methods.

  10. Diastereoselective and enantioselective reduction of tetralin-1,4-dione

    OpenAIRE

    Kündig, E Peter; Enriquez-Garcia, Alvaro

    2008-01-01

    Summary Background The chemistry of tetralin-1,4-dione, the stable tautomer of 1,4-dihydroxynaphthalene, has not been explored previously. It is readily accessible and offers interesting opportunities for synthesis. Results The title reactions were explored. L-Selectride reduced the diketone to give preferentially the cis-diol (d.r. 84 : 16). Red-Al gave preferentially the trans-diol (d.r. 13 : 87). NaBH4, LiAlH4, and BH3 gave lower diastereoselectivities (yields: 76–98%). Fractional crystall...

  11. Main regularities of radiolytic transformations of bifunctional organic compounds

    International Nuclear Information System (INIS)

    Petryaev, E.P.; Shadyro, O.I.

    1985-01-01

    General regularities of the radiolysis of bifunctional organic compounds (α-diols, ethers of α-diols, amino alcohols, hydroxy aldehydes and hydroxy asids) in aqueous solutions from the early stages of the process to formation of finite products are traced. It is pointed out that the most characteristic course of radiation-chemical, transformation of bifunctional compounds in agueous solutions in the fragmentation process with monomolecular decomposition of primary radicals of initial substrances and simultaneous scission of two vicinal in respect to radical centre bonds via five-membered cyclic transient state. The data obtained are of importance for molecular radiobiology

  12. Mutagenicity, stable DNA adducts, and abasic sites induced in Salmonella by phenanthro[3,4-b]- and phenanthro[4,3-b]thiophenes, sulfur analogs of benzo[c]phenanthrene

    Energy Technology Data Exchange (ETDEWEB)

    Swartz, Carol D. [Department of Environmental Science and Engineering, University of North Carolina, Chapel Hill, NC 27599 (United States); King, Leon C.; Nesnow, Stephen [Environmental Carcinogenesis Division, US Environmental Protection Agency, Research Triangle Park, NC, 27711 (United States); Umbach, David M. [Biostatistics Branch, National Institute of Environmental Health Sciences, National Institutes of Health, DHHS, Research Triangle Park, NC 27709 (United States); Kumar, Subodh [Environmental Toxicology and Chemistry Laboratory, Great Lakes Center, State University of New York College at Buffalo, Buffalo, NY 14222 (United States); DeMarini, David M. [Environmental Carcinogenesis Division, US Environmental Protection Agency, Research Triangle Park, NC, 27711 (United States)], E-mail: demarini.david@epa.gov

    2009-02-10

    Sulfur-containing polycyclic aromatic hydrocarbons (thia-PAHs or thiaarenes) are common constituents of air pollution and cigarette smoke, but only a few have been studied for health effects. We evaluated the mutagenicity in Salmonella TA98, TA100, and TA104 of two sulfur-containing derivatives of benzo[c]phenanthrene, phenanthro[3,4-b]thiophene (P[3,4-b]T), and phenanthro[4,3-b]thiophene (P[4,3-b]T) as well as their dihydrodiol and sulfone derivatives. In addition, we assessed levels of stable DNA adducts (by {sup 32}P-postlabeling) as well as abasic sites (by an aldehydic-site assay) produced by six of these compounds in TA100. P[3,4-b]T and its 6,7- and 8,9-diols, P[3,4-b]T sulfone, P[4,3-b]T, and its 8,9-diol were mutagenic in TA100. P[3,4-b]T sulfone, the most potent mutagen, was approximately twice as potent as benzo[a]pyrene in both TA98 and TA100. Benzo-ring dihydrodiols were much more potent than K-region dihydrodiols, which had little or no mutagenic activity in any strain. P[3,4-b]T sulfone produced abasic sites and not stable DNA adducts; the other five compounds examined, B[c]P, B[c]P 3,4-diol, P[3,4-b]T, P[3,4-b]T 8,9-diol, and P[4,3-b]T 8,9-diol, produced only stable DNA adducts. P[3,4-b]T sulfone was the only compound that produced significant levels of frameshift mutagenicity and induced mutations primarily at GC sites. In contrast, B[c]P, its 3,4-diol, and the 8,9 diols of the phenanthrothiophenes induced mutations primarily at AT sites. P[3,4-b]T was not mutagenic in TA104, whereas P[3,4-b]T sulfone was. The two isomeric forms (P[3,4-b]T and P[4,3-b]T) are apparently activated differently, with the latter, but not the former, involving a diol pathway. This study is the first illustrating the potential importance of abasic sites in the mutagenicity of thia-PAHs.

  13. Two new furostanol saponins from Tribulus terrestris.

    Science.gov (United States)

    Xu, Ya-Juan; Xu, Tun-Hai; Zhou, Hai-Ou; Li, Bo; Xie, Sheng-Xu; Si, Yun-Shan; Liu, Yue; Liu, Tong-Hua; Xu, Dong-Ming

    2010-05-01

    Two new furostanol saponins were isolated from the fruits of Tribulus terrestris L. Their structures were established as 26-O-beta-D-glucopyranosyl-(25S)-5alpha-furost-20(22)-en-3beta,26-diol-3-O-alpha-L-rhamnopyranosyl-(1 --> 2)-[beta-D-glucopyranosyl-(1 --> 4)]-beta-D-galactopyranoside (1) and 26-O-beta-D-glucopyranosyl-(25S)-5alpha-furost-20(22)-en-12-one-3beta,26-diol-3-O-beta-D-galactopyranosyl-(1 --> 2)-beta-D-glucopyranosyl-(1 --> 4)-beta-D-galactopyranoside (2) on the basis of spectroscopic data as well as chemical evidence.

  14. Chemical Investigation of Euphorbia schimperi C. Presl

    Directory of Open Access Journals (Sweden)

    Azza R. Abdel-Monem

    2008-08-01

    Full Text Available Three triterpenoids; cycloart-25-en-3β,24-diol, cycloart-23-en-3β,25-diol, and a -amyrin, in addition to b -sitosterol- b -D-O-glucoside, scopoletin, luteolin and kampferol were isolated for the first time from the chloroform fraction of the alcoholic extract of Euphorbia schimperi C. Presl (F. Euphorbiaceae. The isolated compounds were identified using different spectroscopic methods (EIMS, 1HNMR, 13CNMR, HMQC, HMBC and COSY. The cytotoxic activity of the chloroform fraction was also studied using brain and breast carcinoma cell lines.

  15. Nitrite-mediated hydrolysis of epoxides catalyzed by halohydrin dehalogenase from Agrobacterium radiobacter AD1 : A new tool for the kinetic resolution of epoxides

    NARCIS (Netherlands)

    Hasnaoui, Ghania; Lutje Spelberg, Jeffrey H.; de Vries, Erik; Tang, Lixia; Hauer, Bernhard; Janssen, Dick B.

    2005-01-01

    Halohydrin dehalogenase obtained from Agrobacterium radiobacter AD1, has been tested for the nitrite-mediated ring opening of epoxides. This reaction mainly leads to the formation of unstable hydroxynitrite ester intermediates, which can be further hydrolyzed to the corresponding diols. This

  16. Characterization of lipids in complex samples using comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry

    NARCIS (Netherlands)

    Jover, E.; Adahchour, M.; Bayona, J.M.; Vreuls, R.J.J.; Brinkman, U.A.T.

    2005-01-01

    Most lipids are a complex mixture of classes of compounds such as fatty acids, fatty alcohols, diols, sterols and hydroxy acids. In this study, the suitability of comprehensive two-dimensional gas chromatography coupled to a time-of-light mass spectrometer is studied for lipid characterization in

  17. Polyol mediated nano size zinc oxide and nanocomposites with poly(methyl methacrylate

    Directory of Open Access Journals (Sweden)

    2011-07-01

    Full Text Available Organophilic nano ZnO particles have been synthesized in various diols (ethylene glycol – EG, 1,2 propane diol – PD, 1,4 butane diol – BD and tetra(ethylene glycol – TEG in the presence of p-toluenesulfonic acid, p-TsOH, as an end capping agent. The addition of p-TsOH reduces the ZnO particle size and increases its crystallite size. With increasing diol main chain length the ZnO particle size increases (EG (32 nm < PD (33 nm < BD (72 nm < TEG (86 nm. Using the assynthesized and unmodified ZnO nanocomposites with poly(methyl methacrylate, PMMA, matrix have been prepared by the in-situ bulk polymerization of methyl methacrylate, MMA. The addition of surface modifiers is avoided which is an advantage for the application since they can influence other properties of the material. ZnO particles, especially those with smaller particle sizes (EG – 32 nm, PD – 33 nm showed enhanced effect on the thermal stability of PMMA, ultraviolet, UV, absorption and transparency for visible light. Transparent materials with high UV absorption and with enhanced resistance to sunlight were obtained by optimizing the nanocomposite preparation procedure using ZnO particles of about 30 nm size in concentrations between 0.05 and 0.1 wt%. The reported nanocomposite preparation procedure is compatible with the industrial process of PMMA sheet production.

  18. A method for tissue extraction and determination of prostate concentrations of endogenous androgens by radioimmunoassay

    International Nuclear Information System (INIS)

    Albert, J.; Geller, J.; Geller, S.; Lopez, D.

    1976-01-01

    A method for simultaneously determining concentrations of major androgens in prostate has been developed. Extraction techniques used to isolate the androgens from minced tissue include homogenization with high-speed blades in Delsal's solvent mixture, adsorption to silica gel, followed by column and one thin-layer chromatography (TLC). Radioimmunoassays (RIA) of small aliquots of TLC eluates are used to quantitate picogram amounts of 5α-dihydrotestosterone (DHT) and 5α-androstanediols (Diol) and to estimate testosterone (T) and androstenedione (Ad). Contamination of blanks was reduced to RIA sensitivity limits primarily by treatment of glassware in a self-cleaning oven. The specificity of the method for each androgen was established by TLC separations of known prostate metabolites, antisera specificities, and parallelism of sample aliquots to androgen RIA standards. The overall precision, in terms of coefficients of variation, was 21% for DHT and 24% for Diol. T and Ad could not be measured with acceptable precision because their very low concentrations in prostate (<=0.5 ng/g tissue) were less than RIA sensitivity limits. Accuracy studies indicated recoveries ranging from 96% for Diol to 121% for DHT. In human benign hypertrophic prostate tissue, DHT averaged 153 ng/g soluble protein (5.8 ng/g tissue) which was 17 times higher than values obtained in human spleen and kidney; Diol in prostate showed no consistent differences from values noted in kidney or spleen

  19. Radioimmunoassay of steroids in homogenates and subcellular fractions of testicular tissue

    International Nuclear Information System (INIS)

    Campo, S.; Nicolau, G.; Pellizari, E.; Rivarola, M.A.

    1977-01-01

    Radioimmunoassays for testosterone (T), dihydrotestosterone (DHT) and 5alpha-androstan-3alpha, 17beta-diol (DIOL) in homogenates of whole testis, interstitial tissue and seminiferous tubules as well as subcellular fractions of the latter were developed. Steroids were extracted with acetone, submitted to several solvent partitions and isolated by a celite: propylene glycol: ethylene glycol column chromatography. Anit-T serum was used for the assay of T and DTH, and a specific anti-Diol serum for DIOL. Subcellular fractions were separated by differential centrifugation. The nuclear fraction was purified by centrifugation in a dense sucrose buffer followed by several washings. Losses were corrected according to recovery of DNA. Optimal conditions for purification of acetone extracts at minimal losses were established. Validation of the method was studied testing linear regression of logit-log transformations of standard curves and parallelism with unknowns. T was the steroid present in higher concentrations in all samples studied. It is concluded that the present method for determination of endogenous androgen concentrations in testicular tissue is valid and might be useful in studing testicular function. (orig.) [de

  20. Chiral building blocks from biomass: 2,5-Diamino-2,5-dideoxy-1,4-3,6-dianhydroiditol

    NARCIS (Netherlands)

    Thiyagarajan, S.; Gootjes, L.; Vogelzang, W.; Wu, J.; Haveren, van J.; Es, van D.S.

    2011-01-01

    Isohexides (isomannide (endo-endo), isosorbide (endo-exo), and isoidide (exo-exo) are a group of renewable bio-based building blocks that received considerable attention among the polymer industries because these rigid bicyclic diols have several interesting properties in polymer applications.1 We

  1. Polycarbonate-based polyurethane elastomers: temperature-dependence of tensile properties

    Czech Academy of Sciences Publication Activity Database

    Hrdlička, Z.; Kuta, A.; Poreba, Rafal; Špírková, Milena

    2014-01-01

    Roč. 68, č. 2 (2014), s. 233-238 ISSN 0366-6352 R&D Projects: GA ČR GAP108/10/0195 Institutional support: RVO:61389013 Keywords : polyurethane * elastomer * polycarbonate diol Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.468, year: 2014

  2. Aliphatic polycarbonate-based polyurethane elastomers and nanocomposites. I. The influence of hard-segment content and macrodiol-constitution on bottom-up self-assembly

    Czech Academy of Sciences Publication Activity Database

    Špírková, Milena; Poreba, Rafal; Pavličevič, Jelena; Kobera, Libor; Baldrian, Josef; Pekárek, Michal

    2012-01-01

    Roč. 126, č. 3 (2012), s. 1016-1030 ISSN 0021-8995 R&D Projects: GA ČR GAP108/10/0195 Institutional research plan: CEZ:AV0Z40500505 Keywords : polyurethane elastomer * polycarbonate diol * nanocomposite Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.395, year: 2012

  3. Aliphatic polycarbonate-based polyurethane elastomers and nanocomposites. II. Mechanical, thermal, and gas transport properties

    Czech Academy of Sciences Publication Activity Database

    Poreba, Rafal; Špírková, Milena; Brožová, Libuše; Lazić, N.; Pavličevič, Jelena; Strachota, Adam

    2013-01-01

    Roč. 127, č. 1 (2013), s. 329-341 ISSN 0021-8995 R&D Projects: GA ČR GAP108/10/0195 Institutional research plan: CEZ:AV0Z40500505 Keywords : polyurethane elastomer * nanocomposite * polycarbonate diol Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.640, year: 2013

  4. Absolute configuration of some dinorlabdanes from the copaiba oil

    Energy Technology Data Exchange (ETDEWEB)

    Romero, Adriano L.; Baptistela, Lucia H.B.; Imamura, Paulo M. [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Inst. de Quimica], e-mail: imam@iqm.unicamp.br

    2009-07-01

    A novel ent-dinorlabdane ({iota})-13(R)-14,15-dinorlabd-8(17)-ene-3,13-diol was isolated from commercial copaiba oil along with two known dinorlabdanes. The absolute configuration of these dinorditerpenes was established for the first time through synthesis starting from known ({iota})-3-hydroxycopalic acid, which was also isolated from the same oleoresin. (author)

  5. Comparison of solvation dynamics of electrons in four polyols

    Energy Technology Data Exchange (ETDEWEB)

    Lampre, I.; Pernot, P.; Bonin, J. [Laboratoire de Chimie Physique/ELYSE, Universite Paris-Sud 11, UMR 8000, Bat. 349, Orsay F-91405 (France); CNRS, Orsay F-91405 (France); Mostafavi, M. [Laboratoire de Chimie Physique/ELYSE, Universite Paris-Sud 11, UMR 8000, Bat. 349, Orsay F-91405 (France); CNRS, Orsay F-91405 (France)], E-mail: mehran.mostafavi@lcp.u-psud.fr

    2008-10-15

    Using pump-probe transient absorption spectroscopy, we studied the solvation dynamics of the electron in liquid polyalcohols: ethane-1,2-diol, propane-1,2-diol, propane-1,3-diol and propane-1,2,3-triol. Time-resolved absorption spectra ranging from 440 to 720 nm were measured. Our study shows that the excess electron in the diols presents an intense and wide absorption band in the visible and near-IR spectral domain at early time after two-photon ionization of the neat solvent. Then, for the first tens of picoseconds, the electron spectrum shifts toward the blue domain and its bandwidth decreases as the red part of the initial spectrum rapidly drops, while the blue part hardly evolves. In contrast, in the triol, the absorption spectrum of the electron is early situated in the visible range after the pump pulse and then solely evolves in the red part. The Bayesian data analysis of the observed picosecond solvation dynamics with different models is in favor of a heterogeneous continuous relaxation. That is corroborated by the analogy between the change in the absorption band with increasing time or decreasing temperature. That tends to indicate a similar organization disorder of the solvent. Moreover, the electron solvation dynamics is very fast in propane-1,2,3-triol despite its high viscosity and highlight the role of the OH-group in that process.

  6. Influence of gamma radiation on the crosslinking properties of oligo-butadiene-base polyurethane elastomers

    International Nuclear Information System (INIS)

    Dedgaonkar, V.G.

    1994-01-01

    Liquid oligo-butadiene-base diol was cured by gammas when a diisocyanate and a triol were present. The NCO/OH ratio was at unity. Radiation brought about crosslink networks through urethane linkages and among polybutadiene segments. (author). 5 refs., 1 tab

  7. Synthesis of symmetrical and non-symmetrical bivalent neurotransmitter ligands

    DEFF Research Database (Denmark)

    Stuhr-Hansen, Nicolai; Andersen, Jacob; Thygesen, Mikkel Boas

    2016-01-01

    A novel procedure for synthesis of bivalent neurotransmitter ligands was developed by reacting O-benzyl protected N-nosylated dopamine and serotonin with alkyl- or PEG-linked diols under Fukuyama-Mitsunobu conditions in the presence of DIAD/PPh3 generating three different bivalent neurotransmitte...

  8. 21 CFR 178.3480 - Fatty alcohols, synthetic.

    Science.gov (United States)

    2010-04-01

    ... derived lauryl alcohol permitted as an intermediate in the synthesis of sodium lauryl sulfate used in..._locations.html. (1) Synthetic fatty alcohols. (i) Hexyl, octyl, decyl, lauryl, myristyl, cetyl, and stearyl... they may contain not more than 0.8 weight percent total diols. (ii) Lauryl, myristyl, cetyl, and...

  9. Structural and surface properties of novel polyurethane films

    Czech Academy of Sciences Publication Activity Database

    Špírková, Milena; Strachota, Adam; Urbanová, Martina; Baldrian, Josef; Brus, Jiří; Šlouf, Miroslav; Kuta, A.; Hrdlička, Z.

    2009-01-01

    Roč. 24, č. 10 (2009), s. 1185-1189 ISSN 1042-6914 R&D Projects: GA MPO FT-TA3/034; GA AV ČR IAA400500505 Institutional research plan: CEZ:AV0Z40500505 Keywords : montmorillonite * nanoadditives * polybutadiene diol Subject RIV: CD - Macromolecular Chemistry Impact factor: 0.968, year: 2009

  10. Half esters and coating compositions comprising reactions products of half esters and polyepoxides

    NARCIS (Netherlands)

    Blaauw, R.; Mulder, W.J.; Koelewijn, R.; Boswinkel, G.

    2006-01-01

    The present invention relates to half esters based on dicarboxylic acid derivatives and dimer fatty diols, wherein the dimer fatty dio ls are based on dimerised and/or trimerised and/or oligomerised unsaturated fatty acids. The present invention further relates to resin compositions based on the

  11. Lipid constituents of marine sponge Suberites carnosus

    Digital Repository Service at National Institute of Oceanography (India)

    Mishra, P.D.; Wahidullah, S.; DeSouza, L.; Kamat, S.Y.

    Sterols (22E) - 24- methyl-cholest - 4, 8(9), 22(23) - triene - 3, 7 - diol (1) and (22E)-24-methyl-ergost-6, 22(23)-diene-5, 8-epidioxy-3-ol (2), a fatty acid nonadecanoic acid and a fatty ester methyl nonadecanoate have been isolated from...

  12. Partial molar volumes of organic solutes in water. XXVIII. Three aliphatic poly(ethylene glycols) at temperatures T = 298 K–573 K and pressures up to 30 MPa

    International Nuclear Information System (INIS)

    Cibulka, Ivan

    2017-01-01

    Highlights: • Standard molar volumes of three poly(ethylene glycols) in water are presented. • Data were obtained in the range T from (298 to 573) K and p up to 30 MPa. • Data are analyzed and compared with those of similar solutes. - Abstract: Densities of dilute aqueous solutions of three poly(ethylene glycols): 3-oxapentane-1,5-diol (diethylene glycol), 3,6-dioxaoctane-1,8-diol (triethylene glycol), and 3,5,9-trioxaundecane-1,11-diol (tetraethylene glycol) measured in the temperature range from (298 to 573) K and at pressures up to 30 MPa using an automated flow vibrating-tube densimeter are reported. Standard molar volumes were evaluated from the measured data. Present data complement both the previous measurements performed at atmospheric pressure in the temperature range from (278 to 343) K and the data already available for the first member of the homologous series (ethylene glycol). A comparison with data previously measured for the homologous series of linear aliphatic polyethers (poly(ethylene glycol) dimethyl ethers, glymes), diethylene glycol monomethyl ether (3,6-dioxaheptan-1-ol), and selected alkane-α,ω-diols is presented.

  13. Inverted porphyrins and expanded porphyrins: An overview

    Indian Academy of Sciences (India)

    Unknown

    More recently, synthetic porphyrins and porphyrin-like macrocycles have ... one of the meso carbons resulting in the formation of corroles; – (d) Isomeric ... spectroscopic, chemical and physical properties, which can find applications in ..... diol 55 under TFA catalysis yielding 20–28% yield of expected rubyrins 85 and 86 as.

  14. Synthesis, Characterization and Antibacterial Evaluations of the ...

    African Journals Online (AJOL)

    MBI

    2014-06-05

    Jun 5, 2014 ... Schiff base 2-(1-(2-(piperazin-1-yl)ethylimino)ethyl)phenol and its complexes of Mn(II), Ni(II) and Zn(II) were synthesized and ... 1-(2-aminoethyl)piperazine were evaluated for ..... ethylimino)ethyl)benzene-1,3-diol Schiff.

  15. Oxidative cleavage of non-phenolic β-O-4 lignin model dimers by an extracellular aromatic peroxygenase

    Science.gov (United States)

    Matthias Kinne; Marzena Poraj-Kobielska; Rene Ullrich; Paula Nousiainen; Jussi Sipilä; Katrin Scheibner; Kenneth E. Hammel; Martin Hofrichter

    2011-01-01

    The extracellular aromatic peroxygenase of the agaric fungus Agrocybe aegerita catalyzed the H2O2-dependent cleavage of non-phenolic arylgiycerol-ß-aryl ethers (ß-O-4 ethers). For instance 1-(3,4-dimethoxyphenyl)-2-(2-methoxy-phenoxy)propane-1,3-diol, a recalcitrant dimeric lignin model compound that represents the major...

  16. Unusual Conformational Aspects of Some Novel Chiral Non-Racemic Pyridinyl-2-phosphonates

    NARCIS (Netherlands)

    Dros, A.C.; Zijlstra, R.W.J.; Duijnen, P.Th. van; Spek, A.L.; Kooijman, H.; Kellogg, R.M.

    1998-01-01

    Reaction of pyridinyl-2-phosphonyl dichloride (6) with 1-phenyl-2,2-dimethylpropane-1,3-diol (9) leads to the two epimeric 2-oxo-2-(2-pyridinyl)-4-phenyl-5,5-dimethyl-1,3,2-dioxaphosphorinanes (10a,b). These can be separated and the stereochemistry assigned on the basis of 31P NMR spectroscopy. For

  17. Aminodiols via stereocontrolled oxidation of methyleneaziridines.

    Science.gov (United States)

    Rigoli, Jared W; Guzei, Ilia A; Schomaker, Jennifer M

    2014-03-21

    A highly diastereoselective Ru-catalyzed oxidation/reduction sequence of bicyclic methyleneaziridines provides a facile route to complex 1-amino-2,3-diol motifs. The relative anti stereochemistry between the amine and the vicinal alcohol are proposed to result from 1,3-bischelation in the transition state by the C1 and C3 heteroatoms.

  18. Synthesis of a new intercalating nucleic acid 6H-INDOLO[2,3-b] quinoxaline oligonucleotides to improve thermal stability of Hoogsteen-type triplexes

    DEFF Research Database (Denmark)

    Osman, Amany M A; Pedersen, Erik Bjerregaard; Bergman, Jan

    2013-01-01

    A new intercalating nucleic acid monomer X was obtained in high yield starting from alkylation of 4-iodophenol with (S)-(+)-2-(2,2-dimethyl-1,3-dioxolan-4-yl)ethanol under Mitsunobu conditions followed by hydrolysis with 80% aqueous acetic acid to give a diol which was coupled under Sonogashira c...

  19. Production of advanced fuels and of chemicals by yeasts on the basis of second generation feedstocks

    NARCIS (Netherlands)

    Bont, de J.A.M.; Raab, A.; Schilling, M.; Tamame González, M.M.; los Ángeles Santos García, De M.; Martins Dos Santos, V.A.P.; Arjona Antolín, R.; Gutiérrez Gómez, P.

    2014-01-01

    The present invention relates to modified eukaryotic microbial cells that have been engineered for producing fermentation products such as fatty acids, 1-alcohols, [beta]- keto-acids and -alcohols, [beta]-hydroxyacids, 1,3-diols, trans-[Delta]2-fatty acids, alkenes, alkanes and derivatives thereof,

  20. Assessing the stereoselectivity of Serratia marcescens CECT 977 2,3-butanediol dehydrogenase

    NARCIS (Netherlands)

    Medici, R.; Stammes, J.K.; Otten, L.G.; Hanefeld, U.; Kwakernaak, Stender

    2017-01-01

    α-Hydroxy ketones and vicinal diols constitute well-known building blocks in organic synthesis. Here we describe one enzyme that enables the enantioselective synthesis of both building blocks starting from diketones. The enzyme 2,3-butanediol dehydrogenase (BudC) from S. marcescens CECT 977 belongs

  1. High regioselective acetylation of vitamin A precursors using lipase ...

    African Journals Online (AJOL)

    The effect of different reaction parameters was explored on the acylation of primary hydroxyl group of 1,6-diol by lipase B from Candida antarctica catalysis in organic solvent. First, the effect of the organic solvents was investigated, and the highest conversion rate was obtained in n-hexane. Then, the effect of the acyl donor ...

  2. Novel 1,3-dioxanes from apple juice and cider.

    Science.gov (United States)

    Kavvadias, D; Beuerle, T; Wein, M; Boss, B; König, T; Schwab, W

    1999-12-01

    Extracts obtained by XAD solid-phase extraction of apple juice and cider were separated by liquid chromatography on silica gel. Several new 1,3-dioxanes including the known 2-methyl-4-pentyl-1,3-dioxane and 2-methyl-4-[2'(Z)-pentenyl]-1,3-dioxane, were identified in the nonpolar fractions by GC/MS analysis and confirmed by chemical synthesis. The enantioselective synthesis of the stereoisomers of the 1,3-dioxanes was performed using (R)- and (R,S)-octane-1,3-diol and (R)- and (R,S)-5(Z)-octene-1,3-diol as starting material. Comparison with the isolated products indicated that the natural products consisted of a mixture of (2S,4R) and (2R,4R) stereoisomers in the ratio of approximately 10:1, except for 1,3-dioxanes generated from acetone and 2-butanone. It is assumed that the 1, 3-dioxanes are chemically formed in the apples and cider from the natural apple ingredients (R)-octane-1,3-diol, (R)-5(Z)-octene-1, 3-diol, (3R,7R)- and (3R,7S)-octane-1,3,7-triol, and the appropriate aldehydes and ketones, which are produced either by the apples or by yeast during fermentation of the apple juice.

  3. Acetoin catabolism and acetylbutanediol formation by Bacillus pumilus in a chemically defined medium.

    Directory of Open Access Journals (Sweden)

    Zijun Xiao

    Full Text Available BACKGROUND: Most low molecular diols are highly water-soluble, hygroscopic, and reactive with many organic compounds. In the past decades, microbial research to produce diols, e.g. 1,3-propanediol and 2,3-butanediol, were considerably expanded due to their versatile usages especially in polymer synthesis and as possible alternatives to fossil based feedstocks from the bioconversion of renewable natural resources. This study aimed to provide a new way for bacterial production of an acetylated diol, i.e. acetylbutanediol (ABD, 3,4-dihydroxy-3-methylpentan-2-one, by acetoin metabolism. METHODOLOGY/PRINCIPAL FINDINGS: When Bacillus pumilus ATCC 14884 was aerobically cultured in a chemically defined medium with acetoin as the sole carbon and energy source, ABD was produced and identified by gas chromatography--chemical ionization mass spectrometry and NMR spectroscopy. CONCLUSIONS/SIGNIFICANCE: Although the key enzyme leading to ABD from acetoin has not been identified yet at this stage, this study proposed a new metabolic pathawy to produce ABD in vivo from using renewable resources--in this case acetoin, which could be reproduced from glucose in this study--making it the first facility in the world to prepare this new bio-based diol product.

  4. Cycloartane triterpenoids of propolis from Teresina - PI; Triterpenoides tipo cicloartano de propolis de Teresina - PI

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Maria do Socorro Sousa da; Cito, Antonia Maria das Gracas Lopes; Chaves, Mariana H.; Lopes, Jose Arimateia Dantas [Universidade Federal do Piaui, Teresina, PI (Brazil). Dept. de Quimica]. E-mail: gracito@ufpi.br

    2005-09-15

    The chemical study of the propolis produced in Teresina city, state of Piaui, resulted in the identification of six cycloartane triterpenoids: isomangiferolic acid, 24-methylenecycloartane-3{beta},26-diol, mangiferolic acid, mangiferonic acid, ambonic acid and ambolic acid. The substances were characterized by one and two-dimensional {sup 1}H and {sup 13}C NMR analysis. (author)

  5. Triterpenóides tipo cicloartano de própolis de Teresina - PI Cycloartane triterpenoids of propolis from Teresina - PI

    Directory of Open Access Journals (Sweden)

    Maria do Socorro Sousa da Silva

    2005-10-01

    Full Text Available The chemical study of the propolis produced in Teresina city, state of Piaui, resulted in the identification of six cycloartane triterpenoids: isomangiferolic acid, 24-methylenecycloartane-3beta,26-diol, mangiferolic acid, mangiferonic acid, ambonic acid and ambolic acid. The substances were characterized by one and two-dimensional ¹H and 13C NMR analysis.

  6. Fluorination of some highly functionalized cycloalkanes: chemoselectivity and substrate dependence

    Directory of Open Access Journals (Sweden)

    Attila Márió Remete

    2017-11-01

    Full Text Available A study exploring the chemical behavior of some dihydroxylated β-amino ester stereo- and regioisomers, derived from unsaturated cyclic β-amino acids is described. The nucleophilic fluorinations involving hydroxy–fluorine exchange of some highly functionalized alicyclic diol derivatives have been carried out in view of selective fluorination, investigating substrate dependence, neighboring group assistance and chemodifferentiation.

  7. GC-MS analysis of pesticidal essential oils from four Kenyan plants

    African Journals Online (AJOL)

    Gladys

    2015-04-01

    Apr 1, 2015 ... 3Center for Biotechnology Research and Development (CBRD), Kenya Medical Institute(KEMRI), P.O Box, 54840-. 00200 ... Others possess antifungal, insecticidal and antiseptic properties. Essential .... climate, the soil type, and other factors. ..... compounds 3,8-pmenthane-diol (from lemon eucalyptus),.

  8. Novel polycarbonate-based polyurethane elastomers: composition–property relationship

    Czech Academy of Sciences Publication Activity Database

    Špírková, Milena; Pavličevic, J.; Strachota, Adam; Poreba, Rafal; Bera, O.; Kaprálková, Ludmila; Baldrian, Josef; Šlouf, Miroslav; Lazić, N.; Budinski-Simendic, J.

    2011-01-01

    Roč. 47, č. 5 (2011), s. 959-972 ISSN 0014-3057 R&D Projects: GA ČR GAP108/10/0195 Institutional research plan: CEZ:AV0Z40500505 Keywords : polyurethane elastomer * polycarbonate diol * montmorillonite Subject RIV: CD - Macromolecular Chemistry Impact factor: 2.739, year: 2011

  9. Synthesis, characterization, thermal degradation and electrical ...

    African Journals Online (AJOL)

    Poly-4-[(pyridin-2-yl-imino)methyl]benzene-1,3-diol (P-4-PIMBD) was synthesized via the oxidative polycondensation reaction by using sodium hypo chloride (NaOCl) oxidant in an aqueous alkaline medium at 70 oC. The yield of the polymer was found to be 68 %. The structures of the compounds were confirmed by FT-IR, ...

  10. 1,2- and 1,3-dihydroxylated and hydroxynitrogenated monoterpenes as chiral ligands in the asymmetric reformatsky reaction

    International Nuclear Information System (INIS)

    Ribeiro, Carlos Magno R.; Morita, Cristina M.; Maia, Monica P.

    2008-01-01

    This study describes the use of three (-)-α-pinene derivatives, one diol-1,2 [(-)- (1R, 2R, 3S, 5R)-2,6,6-trimethylbicyclo[3.1.1]heptane-2,3-diol 4] and two pyridine-hydroxy derivatives [(+)-(1R,2S,3R,5S)-2,6,6- trimethyl-3-(2-pyridinylmethyl)bicyclo[3.1.1]heptane-3-ol 7 and (-)-(1R,2S,3R,5S)-2,6,6-trimethyl-3-[2-(2-pyridinyl) ethyl]bicyclo[3.1.1]heptane-3-ol 8]; one diol-1,3 [(-)-(1S,2R,5S)-2-(1-hydroxy-1-methylethyl)-5-methylcyclohexanol 5] derived from (+)-isopulegol 2 and one diol-1,3 [(+)-(1R,2R,5R)-2-(1-hydroxy-1-methylethyl)-5-methylcyclohexanol 6] derived from (+)-neoisopulegol 3, as ligands in the asymmetric Reformatsky reaction. The best enantiomeric excess of β-hydroxy ester obtained in the Reformatsky asymmetric reaction was 18% using ligand 6, and the chemical yield of the reactions was 65% on average. (author)

  11. Journal of Chemical Sciences | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Chemical Sciences. Seema Kothari. Articles written in Journal of Chemical Sciences. Volume 113 Issue 1 February 2001 pp 43-54 Organic. Kinetics and mechanism of the oxidation of some diols by benzyltrimethylammonium tribromide · Garima Goswami Seema Kothari Kalyan K Banerji.

  12. Application of HPLC capacity coefficients to characterize the sorption of polycyclic aromatic compounds to humic acid

    DEFF Research Database (Denmark)

    Nielsen, T.; Helweg, C.; Siigur, K.

    1997-01-01

    The sorption coefficients to humic acid of 46 PAC having a wide range in polarity were compared with the capacity coefficients of the PAC to a non-polar HPLC column material (ODS) and a polar one (Diol). It is shown that polar interactions contribute to the sorption of polar PAC in addition...

  13. Synthesis, complexation chemistry and a case of self-recognition of chiral phosphite ligands

    NARCIS (Netherlands)

    Dros, AC; Meetsma, A; Kellogg, RM

    1999-01-01

    Reaction of (R)-(-)-1-phenyl-2,2,3-trimethylbutane-1,3-diol with PCl3 affords trans-(S)-2-chloro-4,4,5,5-tetramethyl-6-(R)-phenyl-1,3,2-dioxaphosphorinane, which couples smoothly with catechol, resorcinol, 2,2-dimethyl-1,3-propanediol and fluorenedimethanol to form the corresponding diphosphites. By

  14. Sea surface temperature variations in the western Mediterranean Sea over the last 20 kyr: A dual-organic proxy (U

    NARCIS (Netherlands)

    Rodrigo-Gámiz, M.; Martínez-Ruiz, F.; Rampen, S.W.; Schouten, S.; Sinninghe Damsté, J.S.

    2014-01-01

    A high-resolution sea surface temperature (SST) reconstruction of the western Mediterranean was accomplished using two independent, algae-based molecular organic proxies, i.e., the U-37(K) index based on long-chain unsaturated ketones and the novel long-chain diol index (LDI) based on the relative

  15. Biotransformation of limonene by bacteria, fungi, yeasts, and plants

    NARCIS (Netherlands)

    Duetz, W.A.; Bouwmeester, H.J.; Beilen, J.B.; Witholt, B.

    2003-01-01

    The past 5 years have seen significant progress in the field of limonene biotransformation, especially with regard to the regiospecificity of microbial biocatalysts. Whereas earlier only regiospecific biocatalysts for the 1,2 position (limonene-1,2-diol) and the 8-position (¿±-terpineol) were

  16. Scientific opinion: Risks for human health related to the presence of 3- and 2-monochloropropanediol (MCPD), and their fatty acid esters, and glycidyl fatty acid esters in food

    NARCIS (Netherlands)

    Hoogenboom, L.A.P.

    2016-01-01

    EFSA was asked to deliver a scientific opinion on free and esterified 3- and 2-monochloropropane-1,2-diol (MCPD) and glycidyl esters in food. Esters of 3- and 2-MCPD and glycidol are contaminants of processed vegetable oils; free MCPDs are formed in some processed foods. The Panel on Contaminants in

  17. Refined hazard characterization of 3-MCPD using benchmark dose modeling

    NARCIS (Netherlands)

    Rietjens, I.M.C.M.; Scholz, G.; Berg, van den I.; Schilter, B.; Slob, W.

    2012-01-01

    3-Monochloropropane-1,2-diol (3-MCPD)-esters represent a newly identified class of food-borne process contaminants of possible health concern. Due to hydrolysis 3-MCPD esters constitute a potentially significant source of free 3-MCPD exposure and their preliminary risk assessment was based on

  18. Hydrolysis of glyoxal in water-restricted environments: formation of organic aerosol precursors through formic acid catalysis.

    Science.gov (United States)

    Hazra, Montu K; Francisco, Joseph S; Sinha, Amitabha

    2014-06-12

    The hydrolysis of glyoxal involving one to three water molecules and also in the presence of a water molecule and formic acid has been investigated. Our results show that glyoxal-diol is the major product of the hydrolysis and that formic acid, through its ability to facilitate intermolecular hydrogen atom transfer, is considerably more efficient than water as a catalyst in the hydrolysis process. Additionally, once the glyoxal-diol is formed, the barrier for further hydrolysis to form the glyoxal-tetrol is effectively reduced to zero in the presence of a single water and formic acid molecule. There are two important implications arising from these findings. First, the results suggest that under the catalytic influence of formic acid, glyoxal hydrolysis can impact the growth of atmospheric aerosols. As a result of enhanced hydrogen bonding, mediated through their polar OH functional groups, the diol and tetrol products are expected to have significantly lower vapor pressure than the parent glyoxal molecule; hence they can more readily partition into the particle phase and contribute to the growth of secondary organic aerosols. In addition, our findings provide insight into how glyoxal-diol and glyoxal-tetrol might be formed under atmospheric conditions associated with water-restricted environments and strongly suggest that the formation of these precursors for secondary organic aerosol growth is not likely restricted solely to the bulk aqueous phase as is currently assumed.

  19. Scientific opinion on the risks for human health related to the presence of 3-and 2-monochloropropanediol (MCPD), and their fatty acid esters, and glycidyl fatty acid esters in food

    DEFF Research Database (Denmark)

    Petersen, Annette

    EFSA was asked to deliver a scientific opinion on free and esterified 3- and 2-monochloropropane-1, 2-diol (MCPD) and glycidyl esters in food. Esters of 3- and 2-MCPD and glycidol are contaminants of processed vegetable oils; free MCPDs are formed in some processed foods. The Panel on Contaminant...

  20. Dehydrogenative Coupling of Primary Alcohols To Form Esters Catalyzed by a Ruthenium N-Heterocyclic Carbene Complex

    DEFF Research Database (Denmark)

    Sølvhøj, Amanda Birgitte; Madsen, Robert

    2011-01-01

    The ruthenium complex [RuCl2(IiPr)(p-cymene)] catalyzes the direct condensation of primary alcohols into esters and lactones with the release of hydrogen gas. The reaction is most effective with linear aliphatic alcohols and 1,4-diols and is believed to proceed with a ruthenium dihydride...

  1. CHARACTERIZATION OF STABLE BENZO(A)PYRENE-7,8-QUINONE-DNA ADDUCTS IN CALF THYMUS DNA

    Science.gov (United States)

    Benzo[alpyrene-7,8-dione (BPQ) is a reactive aldo-keto reductase-mediated product of B[a]P-7,8-diol, a major P450/epoxide hydrolase metabolite of the multi-species carcinogen, B[a]P. The role of BPQ in B[a]P's genotoxicity and carcinogenesis is evolving. Toxicity pathways involvi...

  2. LC/MSMS STUDY OF BENZO[A]PYRENE-7,8-QUINONE ADDUCTION TO GLOBIN TRYPTIC PEPTIDES AND N-ACETYLAMINO ACIDS

    Science.gov (United States)

    Benzo[a]pyrene-7,8-quinone (BPQ) is regarded as a reactive genotoxic compound enzymatically formed from a xenobiotic precursor benzo[a]pyrene-7,8-diol by aldo-keto-reductase family of enzymes. Because BPQ, a Michael electrophile, was previously shown to react with oligonucleotide...

  3. CHARACTERIZATION OF STABLE BENZOLALPYRENE-7,8-QUINONE-DNA ADDUCTS IN CALF THYMUS DNA AND POLYDEOXYNUCLEOTIDES

    Science.gov (United States)

    Bcnzo[a]pyrene-7,8-dione (BPQ) is a reactive aldo-keto reductase-mediated product of B[a]P-7,8-diol, a major P450/epoxide hydrolase metabolite of the multi-species carcinogen, B[a]P. The role of BPQ in B[a]P's genotoxicity and carcinogenesis is evolving. Toxicity pathways involvi...

  4. Steroidal saponins from Tribulus terrestris.

    Science.gov (United States)

    Kang, Li-Ping; Wu, Ke-Lei; Yu, He-Shui; Pang, Xu; Liu, Jie; Han, Li-Feng; Zhang, Jie; Zhao, Yang; Xiong, Cheng-Qi; Song, Xin-Bo; Liu, Chao; Cong, Yu-Wen; Ma, Bai-Ping

    2014-11-01

    Sixteen steroidal saponins, including seven previously unreported compounds, were isolated from Tribulus terrestris. The structures of the saponins were established using 1D and 2D NMR spectroscopy, mass spectrometry, and chemical methods. They were identified as: 26-O-β-d-glucopyranosyl-(25R)-furost-4-en-2α,3β,22α,26-tetrol-12-one (terrestrinin C), 26-O-β-d-glucopyranosyl-(25R)-furost-4-en-22α,26-diol-3,12-dione (terrestrinin D), 26-O-β-d-glucopyranosyl-(25S)-furost-4-en-22α,26-diol-3,6,12-trione (terrestrinin E), 26-O-β-d-glucopyranosyl-(25R)-5α-furostan-3β,22α,26-triol-12-one (terrestrinin F), 26-O-β-d-glucopyranosyl-(25R)-furost-4-en-12β,22α,26-triol-3-one (terrestrinin G), 26-O-β-d-glucopyranosyl-(1→6)-β-d-glucopyranosyl-(25R)-furost-4-en-22α,26-diol-3,12-dione (terrestrinin H), and 24-O-β-d-glucopyranosyl-(25S)-5α-spirostan-3β,24β-diol-12-one-3-O-β-d-glucopyranosyl-(1→4)-β-d-galactopyranoside (terrestrinin I). The isolated compounds were evaluated for their platelet aggregation activities. Three of the known saponins exhibited strong effects on the induction of platelet aggregation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Fluorination of some highly functionalized cycloalkanes: chemoselectivity and substrate dependence.

    Science.gov (United States)

    Remete, Attila Márió; Nonn, Melinda; Fustero, Santos; Haukka, Matti; Fülöp, Ferenc; Kiss, Loránd

    2017-01-01

    A study exploring the chemical behavior of some dihydroxylated β-amino ester stereo- and regioisomers, derived from unsaturated cyclic β-amino acids is described. The nucleophilic fluorinations involving hydroxy-fluorine exchange of some highly functionalized alicyclic diol derivatives have been carried out in view of selective fluorination, investigating substrate dependence, neighboring group assistance and chemodifferentiation.

  6. Application of the Solid-Phase Julia–Lythgoe Olefination in Vitamin D Side-Chain Construction

    Directory of Open Access Journals (Sweden)

    Pierre J. De Clercq

    2006-08-01

    Full Text Available An example of the Julia–Lythgoe attachment of the vitamin D side chain to a solid-phase linked Inhoffen–Lythgoe diol derived CD-ring fragment is reported.

  7. Ring-opening of gamma-valerolactone with amino compounds

    NARCIS (Netherlands)

    Chalid, Mochamad; Heeres, Hero J.; Broekhuis, Antonius A.

    2012-01-01

    Diols obtained by the ring-opening of biomass-based gamma-valerolactone (GVL) are potentially valuable building blocks that can be used as precursors in the manufacture of green polymers and resins. We report here a study on the ring-opening of GVL through adding amine compounds. The reactivity of

  8. New phenolic esters from the resinous exudate of Haplopappus taeda.

    Science.gov (United States)

    Faini, Francesca; Labbé, Cecilia; Torres, René; Rodilla, Jesús M; Silva, Lucía; Delle Monache, Franco

    2007-12-01

    Two new phenolic esters 9-trans-p-coumaroyloxy-alpha-terpineol (1) and 7-trans-p-coumaroyloxy-taedol (2), both endowed with free radical scavenger activity and cleroda-3,13 (E)-dien-15,18-diol (3) for which a cis stereochemistry at the decalin junction was found, were isolated from the resinous exudate from Haplopappus taeda upper parts.

  9. Author Details

    African Journals Online (AJOL)

    Obikeze, KC. Vol 61 (2008) - Articles Characterization and Cardiovascular Effects of (13S)-9α,13α-epoxylabda-6β(19),15(14)diol Dilactone, a Diterpenoid Isolated from Leonotis leonurus. Abstract PDF. ISSN: 0379-4350. AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors ...

  10. Glyoxylate as a reducing agent for manganese(III) in salen scaffold ...

    Indian Academy of Sciences (India)

    being the monohydrate gem-diol forms) followed by the slow electron transfer ... stress and implicated as possible therapeutic agents .... excess HGl at different pHs (1.8–2.5) were set aside ...... sion (UGC), New Delhi in terms of a Teacher Fel-.

  11. Journal of Chemical Sciences | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    An asymmetric route to 2,3-epoxy-syn-1,4-cyclohexane diol derivatives using ring closing ... The phase shows insulator-metal (I-M) transition at low temperature, the ... Synthesis, characterization and self-assembly with gold nanoparticles ... and interfacial behaviour of systems derived from sodium dodecylsulfate and ...

  12. Journal of Chemical Sciences | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    ... in the reduction of PPh2Cl to give [Ru(6-cymene)Cl2(PPh2H)] and the expected phosphinite. The yield of the hydride complex is highest when the alcohol is 1-phenyl-ethane-1,2-diol. All three half-sandwich complexes are characterized by X-ray crystallography. Surprisingly, the conversion of chlorodiphenylphosphine ...

  13. Synthesis of ergostane-type brassinosteroids with modifications in ring A

    Czech Academy of Sciences Publication Activity Database

    Zhabinskii, V.N.; Osiyuk, D.A.; Ermolovich, Y.V.; Chaschina, N.M.; Dalidovich, T.S.; Strnad, Miroslav; Khripach, V.A.

    2017-01-01

    Roč. 13, NOV 2 (2017), s. 2326-2331 ISSN 1860-5397 R&D Projects: GA MŠk(CZ) LO1204 Institutional support: RVO:61389030 Keywords : biosynthetic precursors * brassinosteroids * diols Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Organic chemistry Impact factor: 2.337, year: 2016

  14. Sustainable Chemistry for Biomass Utilization

    DEFF Research Database (Denmark)

    Nielsen, Lasse Bo

    Vanadium catalyzed deoxydehydration (DODH) of vicinal diols to alkenes have been investigated. The aim of the project was to examine the possibility of using an alcohol as both the solvent and the reductant. Development of a process that functions in a polar solvent was thought to be especially i...

  15. Influence of hydrogen bonding on the generation and stabilization

    Indian Academy of Sciences (India)

    Induction and stabilization of liquid crystallinity through hydrogen bonding (HB) are now well-established. Interesting observations made on the influence of HB on LC behaviour of amido diol-based poly(esteramide)s, poly(esteramide)s containing nitro groups and azobenzene mesogen-based polyacrylates will be ...

  16. 15-00443_SI_NP.docx

    Indian Academy of Sciences (India)

    suresh

    Supporting Information. A Facile and Efficient Synthesis of (15R)-Latanoprost from Chiral Precursor Corey Lactone Diol. K VIJENDHARa,b, B SRINIVASb and SATHYANARAYANA BOODIDA*,a. aDepartment of Chemistry, JNTUH College of Engineering Jagtial, Karimnagar 505 501, India. bR&D Division, Aspen Bio Pharma ...

  17. Antioxidant and cytotoxic activity of mono- and bissalicylic acid derivatives

    Directory of Open Access Journals (Sweden)

    Đurendić Evgenija A.

    2014-01-01

    Full Text Available A simple synthesis of mono- and bis-salicylic acid derivatives 1-10 by the transesterification of methyl salicylate (methyl 2-hydroxybenzoate with 3-oxapentane-1,5-diol, 3,6- dioxaoctane-1,8-diol, 3,6,9-trioxaundecane-1,11-diol, propane-1,2-diol or 1-aminopropan- 2-ol in alkaline conditions is reported. All compounds were tested in vitro on three malignant cell lines (MCF-7, MDA-MB-231, PC-3 and one non-tumor cell line (MRC- 5. Strong cytotoxicity against prostate PC-3 cancer cells expressed compounds 3, 4, 6, 9 and 10, all with the IC50 less than 10 μmol/L, which were 11-27 times higher than the cytotoxicity of antitumor drug doxorubicin. All tested compounds were not toxic against the non-tumor MRC-5 cell line. Antioxidant activity of the synthesized derivatives was also evaluated. Compounds 2, 5 and 8 were better OH radical scavengers than commercial antioxidants BHT and BHA. The synthesized compounds showed satisfactory scavenger activity, which was studied by QSAR modeling. A good correlation between the experimental variables IC50 DPPH and IC50 OH and MTI (molecular topological indices molecular descriptors and CAA (accessible Connolly solvent surface area for the new compounds 1, 3, and 5 was observed.

  18. Enantioselective Evans-Tishchenko Reduction of b-Hydroxyketone Catalyzed by Lithium Binaphtholate

    Directory of Open Access Journals (Sweden)

    Makoto Nakajima

    2011-06-01

    Full Text Available Lithium diphenylbinaphtholate catalyzed the enantioselective Evans-Tishchenko reduction of achiral b-hydroxyketones to afford monoacyl-protected 1,3-diols with high stereoselectivities. In the reaction of racemic b-hydroxyketones, kinetic optical resolution occurred in a highly stereoselective manner.

  19. Glycosidically bound flavor compounds of cape gooseberry (Physalis peruviana L.).

    Science.gov (United States)

    Mayorga, H; Knapp, H; Winterhalter, P; Duque, C

    2001-04-01

    The bound volatile fraction of cape gooseberry (Physalis peruviana L.) fruit harvested in Colombia has been examined by HRGC and HRGC-MS after enzymatic hydrolysis using a nonselective pectinase (Rohapect D5L). Forty bound volatiles could be identified, with 21 of them being reported for the first time in cape gooseberry. After preparative isolation of the glycosidic precursors on XAD-2 resin, purification by multilayer coil countercurrent chromatography and HPLC of the peracetylated glycosides were carried out. Structure elucidation by NMR, ESI-MS/MS, and optical rotation enabled the identification of (1S,2S)-1-phenylpropane-1,2-diol 2-O-beta-D-glucopyranoside (1) and p-menth-4(8)-ene-1,2-diol 1-O-alpha-L-arabinopyranosyl-(1-6)-beta-D-glucopyranoside (2). Both glycosides have been identified for the first time in nature. They could be considered as immediate precursors of 1-phenylpropane-1,2-diol and p-menth-4(8)-ene-1,2-diol, typical volatiles found in the fruit of cape gooseberry.

  20. Rhodococcus erythropolis DCL14 Contains a Novel Degradation Pathway for Limonene

    Science.gov (United States)

    van der Werf, Mariët J.; Swarts, Henk J.; de Bont, Jan A. M.

    1999-01-01

    Strain DCL14, which is able to grow on limonene as a sole source of carbon and energy, was isolated from a freshwater sediment sample. This organism was identified as a strain of Rhodococcus erythropolis by chemotaxonomic and genetic studies. R. erythropolis DCL14 also assimilated the terpenes limonene-1,2-epoxide, limonene-1,2-diol, carveol, carvone, and (−)-menthol, while perillyl alcohol was not utilized as a carbon and energy source. Induction tests with cells grown on limonene revealed that the oxygen consumption rates with limonene-1,2-epoxide, limonene-1,2-diol, 1-hydroxy-2-oxolimonene, and carveol were high. Limonene-induced cells of R. erythropolis DCL14 contained the following four novel enzymatic activities involved in the limonene degradation pathway of this microorganism: a flavin adenine dinucleotide- and NADH-dependent limonene 1,2-monooxygenase activity, a cofactor-independent limonene-1,2-epoxide hydrolase activity, a dichlorophenolindophenol-dependent limonene-1,2-diol dehydrogenase activity, and an NADPH-dependent 1-hydroxy-2-oxolimonene 1,2-monooxygenase activity. Product accumulation studies showed that (1S,2S,4R)-limonene-1,2-diol, (1S,4R)-1-hydroxy-2-oxolimonene, and (3R)-3-isopropenyl-6-oxoheptanoate were intermediates in the (4R)-limonene degradation pathway. The opposite enantiomers [(1R,2R,4S)-limonene-1,2-diol, (1R,4S)-1-hydroxy-2-oxolimonene, and (3S)-3-isopropenyl-6-oxoheptanoate] were found in the (4S)-limonene degradation pathway, while accumulation of (1R,2S,4S)-limonene-1,2-diol from (4S)-limonene was also observed. These results show that R. erythropolis DCL14 metabolizes both enantiomers of limonene via a novel degradation pathway that starts with epoxidation at the 1,2 double bond forming limonene-1,2-epoxide. This epoxide is subsequently converted to limonene-1,2-diol, 1-hydroxy-2-oxolimonene, and 7-hydroxy-4-isopropenyl-7-methyl-2-oxo-oxepanone. This lactone spontaneously rearranges to form 3-isopropenyl-6-oxoheptanoate. In

  1. Molecular fossils of diatoms. Applications in petroleum geochemistry and palaeoenvironmental studies

    Energy Technology Data Exchange (ETDEWEB)

    Rampen, S.W.

    2009-06-11

    Diatoms are one of the major groups of algae which originated relatively recently and evolved in the Late Jurassic/Cretaceous. This thesis presents the results of a comprehensive study of diatom lipids in cultures and in the environment and their applications in the age determination of petroleum and in palaeoenvironmental studies. Diatom DNA sequences were analyzed in order to relate the phylogenetic positions of diatoms to the lipid chemotaxonomy. Forty four different sterols were identified in diatoms, with 24-methylcholesta-5,24(28)-dien-3-beta-ol being most common. 24-Methylcholesta-5,22E-dien-3-beta-ol, previously described as a diatom biomarker, was only the fifth most common sterol and absent in some major diatom groups. All identified sterols have been reported in other algae, but within the diatoms, some sterols and sterol compositions seem to be specific for specific phylogenetic clusters. Sterol compositions confirmed the separate phylogenetic position of the genus Attheya, as also indicated by molecular phylogeny and microscopy. 23-Methyl and 23,24-dimethyl sterols, often associated with dinoflagellate algae, were present in a substantial number of diatoms, suggesting that diatoms may also be a major source. Their phylogenetic position suggests that these diatoms originated from a single common ancestor which evolved in the late Jurassic. In addition to 23-methyl and 23,24-dimethyl sterols, the unusual sterol gorgosterol was found in two diatom cultures of the genus Delphineis. 24-Norsterols were found in the diatom species Thalassiosira aff. antarctica and in dinoflagellate cultures. The evolutionary history of dinoflagellates and diatoms explains the stepwise increases of 24-norsterane concentrations, diagenetic products of 24-norsterols, in petroleum. Long-chain 1,14-diols and 12-hydroxy methyl alkanoates were detected in Proboscia diatoms and may be used as indicators for high-nutrient conditions and upwelling. Their distributions varied between

  2. Subject-based steroid profiling and the determination of novel biomarkers for DHT and DHEA misuse in sports.

    Science.gov (United States)

    Van Renterghem, Pieter; Van Eenoo, Peter; Sottas, Pierre-Edouard; Saugy, Martial; Delbeke, Frans

    2010-01-01

    Doping with natural steroids can be detected by evaluating the urinary concentrations and ratios of several endogenous steroids. Since these biomarkers of steroid doping are known to present large inter-individual variations, monitoring of individual steroid profiles over time allows switching from population-based towards subject-based reference ranges for improved detection. In an Athlete Biological Passport (ABP), biomarkers data are collated throughout the athlete's sporting career and individual thresholds defined adaptively. For now, this approach has been validated on a limited number of markers of steroid doping, such as the testosterone (T) over epitestosterone (E) ratio to detect T misuse in athletes. Additional markers are required for other endogenous steroids like dihydrotestosterone (DHT) and dehydroepiandrosterone (DHEA). By combining comprehensive steroid profiles composed of 24 steroid concentrations with Bayesian inference techniques for longitudinal profiling, a selection was made for the detection of DHT and DHEA misuse. The biomarkers found were rated according to relative response, parameter stability, discriminative power, and maximal detection time. This analysis revealed DHT/E, DHT/5β-androstane-3α,17β-diol and 5α-androstane-3α,17β-diol/5β-androstane-3α,17β-diol as best biomarkers for DHT administration and DHEA/E, 16α-hydroxydehydroepiandrosterone/E, 7β-hydroxydehydroepiandrosterone/E and 5β-androstane-3α,17β-diol/5α-androstane-3α,17β-diol for DHEA. The selected biomarkers were found suitable for individual referencing. A drastic overall increase in sensitivity was obtained. The use of multiple markers as formalized in an Athlete Steroidal Passport (ASP) can provide firm evidence of doping with endogenous steroids. Copyright © 2010 John Wiley & Sons, Ltd.

  3. Seasonal lake surface water temperature trends reflected by heterocyst glycolipid-based molecular thermometers

    Science.gov (United States)

    Bauersachs, T.; Rochelmeier, J.; Schwark, L.

    2015-06-01

    It has been demonstrated that the relative distribution of heterocyst glycolipids (HGs) in cultures of N2-fixing heterocystous cyanobacteria is largely controlled by growth temperature, suggesting a potential use of these components in paleoenvironmental studies. Here, we investigated the effect of environmental parameters (e.g., surface water temperatures, oxygen concentrations and pH) on the distribution of HGs in a natural system using water column filtrates collected from Lake Schreventeich (Kiel, Germany) from late July to the end of October 2013. HPLC-ESI/MS (high-performance liquid chromatography coupled to electrospray ionization-mass spectrometry) analysis revealed a dominance of 1-(O-hexose)-3,25-hexacosanediols (HG26 diols) and 1-(O-hexose)-3-keto-25-hexacosanol (HG26 keto-ol) in the solvent-extracted water column filtrates, which were accompanied by minor abundances of 1-(O-hexose)-3,27-octacosanediol (HG28 diol) and 1-(O-hexose)-3-keto-27-octacosanol (HG28 keto-ol) as well as 1-(O-hexose)-3,25,27-octacosanetriol (HG28 triol) and 1-(O-hexose)-3-keto-25,27-octacosanediol (HG28 keto-diol). Fractional abundances of alcoholic and ketonic HGs generally showed strong linear correlations with surface water temperatures and no or only weak linear correlations with both oxygen concentrations and pH. Changes in the distribution of the most abundant diol and keto-ol (e.g., HG26 diol and HG26 keto-ol) were quantitatively expressed as the HDI26 (heterocyst diol index of 26 carbon atoms) with values of this index ranging from 0.89 in mid-August to 0.66 in mid-October. An average HDI26 value of 0.79, which translates into a calculated surface water temperature of 15.8 ± 0.3 °C, was obtained from surface sediments collected from Lake Schreventeich. This temperature - and temperatures obtained from other HG indices (e.g., HDI28 and HTI28) - is similar to the one measured during maximum cyanobacterial productivity in early to mid-September and suggests that HGs

  4. Comparison of chemical solution deposition systems for the fabrication of lead zirconate titanate thin films

    International Nuclear Information System (INIS)

    Lecarpentier, F.; Daglish, M.; Kemmitt, T.

    2001-01-01

    Ferroelectric thin films of lead zirconate titanate Pb(Zr x Ti 1-x )O 3 (PZT) were prepared from five chemical solution deposition (CSD) systems, namely methoxyethanol, citrate, diol, acetic acid and triethanolamine. Physical characteristics of the solutions, processing parameters and physical and electrical properties of the films were used to assess the relative advantages and disadvantages of the different chemical systems. All the CSD systems decomposed to produce single phase perovskite PZT at temperatures above 650 deg C. Thin film deposition was influenced by the specific characteristics of each system such as wetting on the substrate and viscosity. Distinct precursor effects on the thin film crystallinity and electrical performance were revealed. The diol route yielded films with the highest crystallite size, highest permittivity and lowest loss tangent. The relative permittivity exhibited by films made by the other routes were 25% to 35% lower at equivalent thicknesses. Copyright (2001) The Australian Ceramic Society

  5. Synthesis of monoterpene piperidines from the iridoid glucoside antirrhinoside

    DEFF Research Database (Denmark)

    Franzyk, Henrik; Frederiksen, Signe Maria; Jensen, Søren Rosendal

    1997-01-01

    Synthesis of five novel piperidine monoterpene alkaloids using the iridoid glucoside antirrhinoside as a synthon is described. Two strategies for their preparation were investigated: the first possible pathway involved an intermediate diol from which the piperidine ring was expected to be constru......Synthesis of five novel piperidine monoterpene alkaloids using the iridoid glucoside antirrhinoside as a synthon is described. Two strategies for their preparation were investigated: the first possible pathway involved an intermediate diol from which the piperidine ring was expected...... to be constructed via reaction of its ditosylate with an amine; the second strategy involved a double reductive amination as the key step to the piperidine ring, which proved successful. The stereochemistry of C-5 and C-9 in the obtained piperidine monoterpenes was the same as that reported for alfa...

  6. Flow cytometric measurement of the metabolism of benzo [a] pyrene by mouse liver cells in culture

    International Nuclear Information System (INIS)

    Bartholomew, J.C.; Wade, C.G.; Dougherty, K.

    1984-01-01

    The metabolism of benzo[a]pyrene in individual cells was monitored by flow cytometry. The measurements are based on the alterations that occur in the fluorescence emission spectrum of benzo[a]pyrene when it is converted to various metabolities. Using present instrumentation the technique could easily detect 1 x 10/sup 6/ molecules per cells of benzo [a]pyrene and 1 x 10/sup 7/ molecules per cell of the diol epoxide. The analysis of C3H IOT 1/2 mouse fibroblasts growing in culture indicated that there was heterogeneity in the conversion of the parent compound into diol epoxide derivative suggesting that some variation in sensitivity to transformation by benzo[a]pyrene may be due to differences in cellular metabolism

  7. Flow cytometric measurement of the metabolism of benzo[a]pyrene by mouse liver cells in culture

    International Nuclear Information System (INIS)

    Bartholomew, J.C.; Wade, C.G.; Dougherty, K.K.

    1984-01-01

    The metabolism of benzo[a]pyrene in individual cells was monitored by flow cytometry. The measurements are based on the alterations that occur in the fluorescence emission spectrum of benzo[a]pyrene when it is converted to various metabolites. Using present instrumentation the technique could easily detect 1x10 6 molecules per cells of benzo[a]pyrene and 1x10 7 molecules per cell of the diol epoxide. The analysis of C3H IOT 1/2 mouse fibroblasts growing in culture indicated that there was heterogeneity in the conversion of the parent compound into diol epoxide derivatives suggesting that some variation in sensitivity to transformation by benzo[a]pyrene may be due to differences in cellular metabolism. The technique allows sensitive detection of metabolites in viable cells, and provides a new approach to the study of factors that influence both metabolism and transformation. (orig.)

  8. Synthesis of 3-aminopropyl glycosides of linear β-(1 → 3)-D-glucooligosaccharides.

    Science.gov (United States)

    Yashunsky, Dmitry V; Tsvetkov, Yury E; Grachev, Alexey A; Chizhov, Alexander O; Nifantiev, Nikolay E

    2016-01-01

    3-Aminopropyl glycosides of a series of linear β-(1 → 3)-linked D-glucooligosaccharides containing from 3 to 13 monosaccharide units were efficiently prepared. The synthetic scheme featured highly regioselective glycosylation of 4,6-O-benzylidene-protected 2,3-diol glycosyl acceptors with a disaccharide thioglycoside donor bearing chloroacetyl groups at O-2' and -3' as a temporary protection of the diol system. Iteration of the deprotection and glycosylation steps afforded the series of the title oligoglucosides differing in length by two monosaccharide units. A novel procedure for selective removal of acetyl groups in the presence of benzoyl ones consisting in a brief treatment with a large excess of hydrazine hydrate has been proposed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Copolímeros de poliuretano del tipo poli[(hexametilencarbamatobutanodiol- co-(carbonato-co-éster

    Directory of Open Access Journals (Sweden)

    Borja Fernández-d'Arlas

    2016-12-01

    Full Text Available Los poliuretanos segmentados termoplástico elastoméricos (PUSTE comprenden una familia de materiales muy versátiles debido a su potencial empleo en diversos campos tales como biomedicina. Entre los PUSTE los formados por policarbonatos dioles y diisocianatos alifáticos son especialmente atractivos debido a su bioestabilidad y biocompatibilidad. En este trabajo se presentan los resultados del análisis morfológico y conducta mecánica de una familia de PUSTEs formados por 1,6-hexametilen diisocianato (HDI, 1,4-butanodiol (BD y un copolímero cauchoso de policaprolactona y polihexametilen carbonato diol, PCL-b-PHMC-b-PCL, sintetizados con distinta relación entre bloques rígidos (HDI-BD y copolímero cauchoso.

  10. Transformation of ergosterol peroxide to cytotoxic substances by rat intestinal bacteria.

    Science.gov (United States)

    Lee, Joo-Sang; Ma, Chao-Mei; Park, Dong-Ki; Yoshimi, Yasuharu; Hatanaka, Minoru; Hattori, Masao

    2008-05-01

    Ergosterol peroxide (EPO, 1) is a major antitumor sterol produced by edible or medicinal mushrooms. Following oral administration of 1 to rats or anaerobic in vitro incubation of 1 with rat fecal bacteria, three metabolites were detected and their structures were identified to be 5alpha,6alpha-epoxyergosta-8(14),22-diene-3beta,7alpha-diol (M1, 2), 5alpha,6alpha-epoxyergosta-8,22-diene-3beta,7alpha-diol (M2, 3), and 5alpha,6alpha-epoxy-3beta-hydroxyergosta-22-ene-7-one (M3, 4) by spectroscopic analysis. Of these, M2 and M3 showed more potent inhibitory activity than the original compound 1 against proliferation of CACO-2, WiDr, DLD-1 and Colo320 human colorectal adenocarcinoma cells. These findings suggest that bacterial metabolites of EPO play a significant role in its cytotoxic activity against human colorectal cancer cells.

  11. Determinación de entalpías de mezcla de sistemas muy viscosos usando un ITC y un microcalorímetro de flujo de construcción propia

    OpenAIRE

    Salmerón Hernández, Víctor

    2016-01-01

    Programa de doctorado: Física, Matemáticas, Geología y Clima. La fecha de publicación es la fecha de lectura [ES]Para la presente memoria se han determinado las entalpías molares de exceso HE, a 298.15 K, a la presión atmosférica normal y para todo el intervalo de fracciones molares x, de diversos sistemas binarios del tipo amida + 1,2-diol y agua + 1,2-diol, con el objetivo de valorar la capacidad de operación de un ITC comercial y un microcalorímetro de flujo (FM) construido en nuestro l...

  12. Carotenoids in the cells of the alga Trentepohlia gobii Meyer

    Directory of Open Access Journals (Sweden)

    Bazyli Czeczuga

    2014-01-01

    Full Text Available Column-, and thin-layer chromatography revealed the presence of the following carotenoids in the cells of the species Trentepohlia gobii Meyer from cobbles in the river Urmi in the Badzhal mountains of Khabarovsk Territory in the Far East: ß, ß-carotene, ß, ε-carotene, ß, ß-carotene-2-ol, ß, ε-carotene-2-ol, ß, ß-carotene-2, 2'-diol, 5,6-epoxy-5,6-dihydro-ß, ß-carotene-2-ol, 5,6-epoxy-5,6-dihydro-ß, ε-carotene-2-ol and 5,6,5',6'-diepoxy-5,6,5',6'-tetrahydro-ß, ß-carotene-2,2'-diol.

  13. Synthesis, Characterization and Tribological Evaluation of New Generation Materials for Aluminum Cold Rolling Oils

    Directory of Open Access Journals (Sweden)

    Ponnekanti Nagendramma

    2016-06-01

    Full Text Available The present concept of being globally “green” puts additional demands on lubricants. They are to be biodegradable and ecofriendly. Therefore, in a search for alternate lubricants meeting the above demands, we have synthesized biodegradable new generation esters using alcohols such as 2,2-dimethyl-1,3-propane diol and 2,2-diethyl-1,3-propane diol and fatty acids like caproic and 2-ethyl caproic in presence of indigenous ion exchange resin catalyst. The synthesized esters were analyzed and characterized for their physico chemical properties. In addition, with a view to finding out the possibility of using these esters as aluminum cold rolling oils, their lubricity characteristics, biodegradability and toxicity were also investigated. The products were found to have good potential for use in biodegradable aluminum cold rolling oils meeting IS: 14385-2002 specification.

  14. Application of gas chromatography-mass spectrometry/combustion/isotope ratio mass spectrometry (GC-MS/C/IRMS) to detect the abuse of 17β-estradiol in cattle.

    Science.gov (United States)

    Janssens, Geert; Mangelinckx, Sven; Courtheyn, Dirk; Prévost, Stéphanie; De Poorter, Geert; De Kimpe, Norbert; Le Bizec, Bruno

    2013-07-31

    Although the ability to differentiate between endogenous steroids and synthetic homologues on the basis of their (13)C/(12)C isotopic ratio has been known for over a decade, this technique has been scarcely implemented for food safety purposes. In this study, a method was developed using gas chromatography-mass spectrometry/combustion/isotope ratio mass spectrometry (GC-MS/C/IRMS) to demonstrate the abuse of 17β-estradiol in cattle, by comparison of the (13)C/(12)C ratios of the main metabolite 17α-estradiol and an endogenous reference compound (ERC), 5-androstene-3β,17α-diol, in bovine urine. The intermediate precisions were determined as 0.46 and 0.26‰ for 5-androstene-3β,17α-diol and 17α-estradiol, respectively. This is, to the authors' knowledge, the first reported use of GC-MS/C/IRMS for the analysis of steroid compounds for food safety issues.

  15. Thermoplastic polyurethanes from undecylenic acid-based soft segments: structural features and release properties.

    Science.gov (United States)

    Lluch, Cristina; Lligadas, Gerard; Ronda, Joan C; Galià, Marina; Cádiz, Virginia

    2013-05-01

    A set of thermoplastic polyurethanes is synthesized, combining undecylenic acid-derived telechelic diols as soft segments and 1,4-butanediol/4,4'-methylenebis(phenylisocyanate) as a hard segment (HS). These polymers are fully chemically and physically characterized by means of NMR and Fourier transform IR (FTIR) spectroscopy, size-exclusion chromatography (SEC), DSC, thermogravimetric analysis (TGA), tensile testing, and contact angle measurements. The obtained results reveal that both the molecular weight of the diol and the HS content greatly influence the physical and mechanical properties of these polymers. In addition, given the potential use of these materials for biomedical applications, hydrolytic degradation, their biocompatibility using a human fibroblast cell line, and performance as drug delivery carriers are evaluated. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Microbiological and chemical transformations of argentatin B.

    Science.gov (United States)

    Maatooq, Galal T

    2003-01-01

    Argentatin B is a naturally occurring tetracyclic triterpene isolated from Parthenium argentatum x P. tomentosa. It was microbiologically transformed to 16, 24-epoxycycloartan-3alpha, 25-diol, (isoargentatin D), by Nocardia corallina var. taoka ATCC 31338, Mycobacterium species NRRL B3683 and Septomyxa affinis ATCC 6737. The later microbe also produced 16, 24-epoxycycloartan-3beta, 25-diol (argentatin D) and 1, 2-didehydroargentatin B, (isoargentatin D). Sodium hydroxide converted argentatin B to argentatin D and isoargentatin D. Hydrochloric acid treatment gave cycloartan-25-ol-3, 24-dione. Cerium sulfate/sulfuric acid/aqueous methanol induced scission of the isopropanol moiety and provided an isomeric mixture of 24-methoxy-25-27-trinorargentatin B. Oxidation of this isomeric mixture with pyridinium chlorochromate, selectively, attacked the isomer with the equatorial proton at position-24 to give the corresponding lactone, 24-oxo-25-27-trinorargentatin B. The produced compounds were characterized by spectroscopic methods.

  17. A Mild Catalytic Oxidation System: FePcOTf/H2O2 Applied for Cyclohexene Dihydroxylation

    Directory of Open Access Journals (Sweden)

    Baocheng Zhou

    2015-05-01

    Full Text Available Iron (III phthalocyanine complexes were employed for the first time as a mild and efficient Lewis acid catalyst in the selective oxidation of cyclohexene to cyclohexane-1,2-diol. It was found that the catalyst FePcOTf shown excellent conversion and moderate selectivity relative to other iron (III phthalocyanine complexes. The optimum conditions of the oxidation reaction catalyzed by FePcOTf/H2O2 have been researched in this paper. Iron (III phthalocyanine triflate (1 mol % as catalyst, hydrogen peroxide as oxidant, methanol as solvent, and a mole ratio of substrate and oxidant (H2O2 of 1:1 were used for achieving moderate yields of 1,2-diols under reflux conditions after eight hours.

  18. Efficient oxidation of alcohols to carbonyl compounds with molecular oxygen catalyzed by N-hydroxyphthalimide combined with a Co species

    Science.gov (United States)

    Iwahama; Yoshino; Keitoku; Sakaguchi; Ishii

    2000-10-06

    Highly efficient catalytic oxidation of alcohols with molecular oxygen by N-hydroxyphthalimide (NHPI) combined with a Co species was developed. The oxidation of 2-octanol in the presence of catalytic amounts of NHPI and Co(OAc)2 under atmospheric dioxygen in AcOEt at 70 degrees C gave 2-octanone in 93% yield. The oxidation was significantly enhanced by adding a small amount of benzoic acid to proceed smoothly even at room temperature. Primary alcohols were oxidized by NHPI in the absence of any metal catalyst to form the corresponding carboxylic acids in good yields. In the oxidation of terminal vic-diols such as 1,2-butanediol, carbon-carbon bond cleavage was induced to give one carbon less carboxylic acids such as propionic acid, while internal vic-diols were selectively oxidized to 1,2-diketones.

  19. Investigation of benzo(a)pyrene-globin adducts

    Energy Technology Data Exchange (ETDEWEB)

    Wallin, H; Jeffre, A M; Santella, R M

    1987-05-01

    The nature of the adducts formed between benzo(a)pyrene (BP) and globin were investigated in animals treated with (/sup 3/H)BP. Modification levels on globin were determined by radioactivity measurements. Since BP tetraols can be released from benzo(a)pyrene diol epoxide modified protein and DNA by acid treatment, globin samples were treated with acid, released tetraols separated by HPLC and quantitated by scintillation counting. In addition, acid released material was measured in competitive enzyme linked immunosorbent assay (ELISA) using antibodies which recognize BP tetraols. Both measurements indicate that only 2% of bound radioactivity could be released as free BP tetraols. These studies indicate that benzo(a)pyrene diol epoxide may not be the major metabolite of BP involved in globin binding. (author). 14 refs.

  20. Radioiodinated ligands for the estrogen receptor: Effect of different 7-cyanoalkyl chains on the binding affinity of novel iodovinyl-6-dehydroestradiols

    International Nuclear Information System (INIS)

    Neto, Carina; Oliveira, Maria Cristina; Gano, Lurdes; Marques, Fernanda; Santos, Isabel; Morais, Goreti Ribeiro; Yasuda, Takumi; Thiemann, Thies; Botelho, Filomena; Oliveira, Carlos F.

    2009-01-01

    Three novel 17α-ethynyl-Δ 6,7 -estra-3,17β-diols and their 17α-[ 125 I]-iodovinyl derivatives, containing different C7-cyanoalkyl chains, were studied as potential radioligands for the estrogen receptor. The influence of the chain length on the biological behaviour of the compounds was assessed through in vitro ER binding assays of the ethynyl derivatives and breast cancer cell uptake studies of the 17α-[ 125 I]-iodovinyl-Δ 6,7 -estra-3,17β-diols. A difference in alkyl chain induced a decrease in ER binding affinities of substances, however, the receptor-binding affinities (RBA) of all compounds were lower than that of estradiol itself. In addition, a non-specific cell binding was observed which is in accordance with the encountered ethynyl RBA values suggesting that the uptake is not ER mediated

  1. Cycloartane triterpenes from marine green alga Cladophora fascicularis

    Science.gov (United States)

    Huang, Xinping; Zhu, Xiaobin; Deng, Liping; Deng, Zhiwei; Lin, Wenhan

    2006-12-01

    Six cycloartanes were isolated from ethanol extract of marine green alga Cladophora fascicularis by column chromatography. Procedure of isolation and description of these compounds are given in this paper. The structures were elucidated as (1). 24-hydroperoxycycloart-25- en-3β-ol; (2). cycloart-25-en-3β 24-diol; (3). 25-hydroperoxycycloart-23-en-3β-ol; (4). cycloart-23-en-3β, 25-diol; (5). cycloart-23, 25-dien-3β-ol; and (6). cycloart-24-en-3β-ol by spectroscopic (MS, ID and 2D NMR) data analysis. Cycloartane derivatives are widely distributed in terrestrial plants, but only few were obtained in the alga. All these compounds that have been isolated from terrestrial plants, were found in the marine alga for the first time.

  2. Material Evaluation of Optical Fibers and Payout Bobbins: An Overview

    Science.gov (United States)

    1990-03-01

    Viscosity at 25"C = 5 cps. Diacrylates 1. 1,4-butane-diol diacrylate 2. Neopentyl glycol diacrylate. Shrinkage = 14.2%; volatilization rate = 0.07 mg...min; b.p. = 1228C at 2 mm; viscosity = 32 cps at 25°C. 3. Diethylene glycol diacrylate 4. 1,6-Hexanediol diacrylate. Volatilization rate - 0.02 mg/min

  3. Waterborne Polymeric Films.

    Science.gov (United States)

    1981-02-01

    polymer of neopentyl glycol (NPC) and isophoronediisocyanate (IPDI) as an example: CH 3 0 CH3 0 CH- HO !Ch,,C h OCNH CH.NHCO, HCCH.OH CIF CH- Groun...copolymer of isophoronediisocyanate with neopentyl glycol and dimethylolpropionic acid. And the solibilitv parameter calculations must include this...copolymer of isophoronediiisocyanate with a diol mixture of 85 inol percent neopentyl glycol and 15 inol percent dimethyl- olpropionic acid. 0 0 0 it 0

  4. Synthesis and purification of /sup 14/C N-2-hydroxyethyl-N-nitrosourea

    Energy Technology Data Exchange (ETDEWEB)

    Perez, G.; Possagno, E.; Caponecchi, G.; Lilla, E.; Polcaro, C.

    1986-04-01

    /sup 14/C N-2-hydroxyethyl-N-nitrosourea was prepared at a specific activity of 30 mCi/mmol and 1.29 mCi/mmol by a two-step synthetic sequence using /sup 14/C ethanolamine as the labelled precursor. Its purification was performed by HPLC using a Lichrosorb-DIOL column eluted by ethyl ether. The overall radiochemical yield was 10%.

  5. Synthesis and purification of 14C N-2-hydroxyethyl-N-nitrosourea

    International Nuclear Information System (INIS)

    Perez, G.; Possagno, E.; Caponecchi, G.; Lilla, E.

    1986-01-01

    14 C N-2-hydroxyethyl-N-nitrosourea was prepared at a specific activity of 30 mCi/mmol and 1.29 mCi/mmol by a two-step synthetic sequence using 14 C ethanolamine as the labelled precursor. Its purification was performed by HPLC using a Lichrosorb-DIOL column eluted by ethyl ether. The overall radiochemical yield was 10%. (author)

  6. An efficient synthesis of S-[gamma]-[(4-trifluoromethyl)phenoxy] benzenepropanamine-[1-[sup 14]C]maleate, an important metabolite of fluoxetine hydrochloride. [Antidepressant, serotonin uptake inhibitor

    Energy Technology Data Exchange (ETDEWEB)

    Wheeler, W.J. (Lilly (Eli) and Co., Indianapolis, IN (United States). Lilly Research Labs.)

    1992-02-01

    S-[gamma]-[(4-Trifluoromethyl)phenoxy]benzenepropanamine-[1-[sup 14]C] maleate has been prepared in six steps from R-(-)1-phenyl-1,2-ethanediol. The isotope was incorporated by the reaction of NaCN-[[sup 14]C] with the tert. butyldimethylsilyl ether of R-(-)1-phenyl-1,2-ethane-diol 2-tosylate. Borane reduction and arylation, followed by salt formation yielded S-[gamma]-[(4-trifluoromethyl)phenoxy]benzenepropanamine-[1-[sup 14]C] maleate. (Author).

  7. An efficient synthesis of S-γ-[(4-trifluoromethyl)phenoxy] benzenepropanamine-[1-14C]maleate, an important metabolite of fluoxetine hydrochloride

    International Nuclear Information System (INIS)

    Wheeler, W.J.

    1992-01-01

    S-γ-[(4-Trifluoromethyl)phenoxy]benzenepropanamine-[1- 14 C] maleate has been prepared in six steps from R-(-)1-phenyl-1,2-ethanediol. The isotope was incorporated by the reaction of NaCN-[ 14 C] with the tert. butyldimethylsilyl ether of R-(-)1-phenyl-1,2-ethane-diol 2-tosylate. Borane reduction and arylation, followed by salt formation yielded S-γ-[(4-trifluoromethyl)phenoxy]benzenepropanamine-[1- 14 C] maleate. (Author)

  8. High-level production of diacetyl in a metabolically engineered lactic acid bacterium

    DEFF Research Database (Denmark)

    2017-01-01

    .1.1.5); water-forming NADH oxidase (E.C. 1.6.3.4); phosphotransacetylase (E.C.2.3.1.8) activity; and optionally devoid of or deleted for genes encoding polypeptides having diacetyl reductase ((R)-acetoin forming; EC: 1.1.1.303); D-acetoin reductase; butanediol dehydrogenase ((R,R)-butane-2,3-diol forming; E...

  9. Chemical composition and evaluation of allelopathic potentials of Adiantum tetraphyllum Humb.and Bonpl. Ex. Willd (Pteridaceae)

    International Nuclear Information System (INIS)

    Melos, Jorge L.R.; Silva, Luciana B.; Peres, Marize T. L. P.; Mapeli, Ana M.; Faccenda, Odival; Anjos, Hatino H.; Torres, Thais G.; Tiviroli, Soraia C.; Batista, Ana L.; Almeida, Felipe G. N.; Flauzino, Natasha S.; Tibana, Leticia A.; Hess, Sonia C.; Honda, Neli K.

    2007-01-01

    Chemical studies of green leaves of A. tetraphyllum afforded β-sitosterol, a mixture containing the ethyl esters of long chain carboxylic acids, 30-normethyl-lupan-20-one, hopan-22-ol, phytol, phyten-3(20)-1,2-diol, quercetin and quercetin-3-O-β-D-glucoside. The structures of the compounds were elucidated by spectroscopic and GC analysis. The allelopathic potentials of the crude ethanolic extract and fractions were evaluated against Lactuca sativa (letuce) and Allium cepa (onion) seeds. (author)

  10. Stereo-specific synthesis of (13r)-manoyl oxide

    DEFF Research Database (Denmark)

    2015-01-01

    The present invention relates to a method for manufacturing enantiomerically pure (13R)-manoyl oxide, said method comprising the steps of contacting geranylgeranyl diphosphate (GGPP) with a class II diterpene synthase to obtain labd-13-en-8,15-diol diphosphate (LPP), and then contacting the LPP...... with a class I diterpene synthase to obtain (13R)-manoyl oxide. The invention further relates to (13R)-manoyl oxide obtained by the method of the invention....

  11. Determination of carbohydrates in fermentation processes by high-performance liquid chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Plaga, A.; Stuempfel, J.; Fiedler, H.P. (Tuebingen Univ. (Germany, F.R.). Fakultaet fuer Biologie)

    1989-11-01

    HPLC is a universal, fast, accurate and selective method for the quantification of carbohydrates during fermentation processes. HPLC is not affected by complex constituents of fermentation media, such as meat extract, soybean meal or distillers solubles. The detection limit of the different investigated carbohydrates by refractive index monitoring ranges between 20 and 40 mg/l using a cation-exchange resin and between 50 and 100 mg/l using amino- or diol-bonded phases. (orig.).

  12. QSPR models based on molecular mechanics and quantum chemical calculations. 2. Thermodynamic properties of alkanes, alcohols, polyols, and ethers

    DEFF Research Database (Denmark)

    Dyekjær, Jane Dannow; Jonsdottir, Svava Osk

    2003-01-01

    Quantitative Structure-Property Relationship (QSPR) models for prediction of various thermodynamic properties of simple organic compounds have been developed. A number of new descriptors are proposed and used alongside with descriptors available within the Codessa program. An important feature...... for alkanes, alcohols, diols, ethers, and oxyalcohols, including cyclic alkanes and alcohols. Several good models, having good predictability, have been developed. To enhance the applicability of the QSPR models, simpler expressions for each descriptor have also been developed. This allows for the prediction...

  13. New Flame-Retardant Poly(ester-imide)s Containing Phosphine Oxide Moieties in the Main Chain: Synthesis and Properties

    OpenAIRE

    FAGHIHI, Khalil

    2014-01-01

    Six new flame-retardant poly(ester-imide)s (9a-f) with high inherent viscosity and containing phosphine oxide moieties in the main chain were synthesized from the polycondensation reaction of N,N-(3,3-diphenylphenyl phosphine oxide) bistrimellitimide diacid chloride (7) with 6 aromatic diols (8a-f) by 2 different methods:--solution and microwave-assisted polycondensation. The results showed that compared to solution polycondensation, the microwave-assisted polycondensation reaction us...

  14. Distributions of Heterocyst Glycolipids in Settling Particulate Matter Record Ecological and Environmental Parameters in a Tropical Lake

    Science.gov (United States)

    Meegan Kumar, D.; Hopmans, E.; S Sinninghe Damsté, J.; Schouten, S.; Bauersachs, T.; Werne, J. P.

    2017-12-01

    Temperature is a critical component of paleoenvironmental reconstructions, yet it is notoriously difficult to measure in terrestrial archives. Presented here is an investigation of unique glycolipids produced by heterocystous cyanobacteria, so-called heterocyst glycolipids (HGs), in the water column of Lake Malawi (East Africa). The goal of the study is to evaluate the potential of HGs to function as a paleotemperature proxy in tropical lacustrine environments. HGs in Lake Malawi were extracted from settling particulate matter (SPM) collected at bi-monthly intervals from 2011 - 2013. Sediment traps were moored in the metalimnion of both the north and south basins of the lake in order to evaluate the spatial and the temporal trends in lipid production and export. This study is the first to analyze HGs in SPM and contains the longest time-series of HG production in a natural environment to date. HGs are consistently present throughout the three-year study period, but maximum fluxes occur annually in December, coincident with the timing of cyanobacterial blooms in the lake. HGs in SPM appear to be sourced from living cyanobacteria populations, indicating rapid export of the lipids through the water column. Temperatures reconstructed with published HG-based indices, which are derived from the relative abundances of HG diols and triols to HG keto-(di)ols, do not accurately reflect the seasonal variability in measured surface water temperatures. Rather, the production of C28 HG keto-ols appears to be related to the timing of heterocyst differentiation. Heterocystous cyanobacteria in Lake Malawi may instead respond to growth temperatures by elongating the alkyl side chain of HG diols, as indicated by increases in the abundance of the C28 HG diol relative to the C26 HG diol with warmer surface water temperatures. Distributions of HGs thus may indeed provide a novel tool for paleotemperature reconstructions in tropical lakes.

  15. Chemical composition and evaluation of allelopathic potentials of Adiantum tetraphyllum Humb.and Bonpl. Ex. Willd (Pteridaceae); Constituintes quimicos e avaliacao do potencial alelopatico de Adiantum tetraphyllum Humb. and Bonpl. Ex. Willd (Pteridaceae)

    Energy Technology Data Exchange (ETDEWEB)

    Melos, Jorge L.R. [Colegio Militar de Campo Grande, MS (Brazil). Secao de Ensino ' C' ; Silva, Luciana B.; Peres, Marize T. L. P.; Mapeli, Ana M.; Faccenda, Odival; Anjos, Hatino H.; Torres, Thais G.; Tiviroli, Soraia C.; Batista, Ana L.; Almeida, Felipe G. N.; Flauzino, Natasha S.; Tibana, Leticia A.; Hess, Sonia C. [Universidade Federal de Mato Grosso do Sul, Campo Grande, MS(Brazil). Dept. de Hidraulica e Transportes; Honda, Neli K. [Universidade Federal de Mato Grosso do Sul, Campo Grande, MS (Brazil). Dept. de Quimica]. E-mail: schess@nin.ufms.br

    2007-03-15

    Chemical studies of green leaves of A. tetraphyllum afforded {beta}-sitosterol, a mixture containing the ethyl esters of long chain carboxylic acids, 30-normethyl-lupan-20-one, hopan-22-ol, phytol, phyten-3(20)-1,2-diol, quercetin and quercetin-3-O-{beta}-D-glucoside. The structures of the compounds were elucidated by spectroscopic and GC analysis. The allelopathic potentials of the crude ethanolic extract and fractions were evaluated against Lactuca sativa (letuce) and Allium cepa (onion) seeds. (author)

  16. Four new ent-kaurane diterpenoids from the fruits of Annona cherimola.

    Science.gov (United States)

    Miyashita, Hiroyuki; Nishida, Makiko; Okawa, Masafumi; Nohara, Toshihiro; Yoshimitsu, Hitoshi

    2010-05-01

    Four new ent-kaurane diterpenoids (16R)-ent-kauran-17,19-diol (1), (16R)-17-hydroxy-ent-kauran-19-oic acid (2), (16S)-17-hydroxy-ent-kauran-19-oic acid (3), and (16R)-17-dimethoxy-ent-kauran-19-oic acid (4) have been isolated from the fresh fruits of Annona cherimola together with eight known compounds. Their structures are determined on the basis of spectroscopic data and optical rotation.

  17. Long-Chain Diacrylate Crosslinkers and Use of PEG Crosslinks in Poly(potassium acrylate-acrylic acid)/Kaolin Composite Superabsorbents

    OpenAIRE

    Koroush Kabiri; Siavash Nafisi; Mohammad jalaledin Zohuriaan-Mehr; Ali Akbar Yousefi

    2013-01-01

    Long-chain diacrylate crosslinkers based on linear α,ω-diols were synthesized and characterized using FTIR and 1H NMR spectroscopy. The highest reaction yield (99.5%) was due to polyethylene glycol diacrylate 1000 (PEGDA-1000). Then, kaolin-containing poly(potassium acrylate-acrylic acid) superabsorbent composites and kaolin-free counterparts were synthesized using PEGDA-1000.The effect of the crosslinker concentration on swelling, rheological and thermo-mechanical properties was investigated...

  18. Column chromatography with almecega resin: a project for experimental organic chemistry

    International Nuclear Information System (INIS)

    Vieira Junior, Gerardo Magela; Carvalho, Adonias Almeida; Gonzaga, Wellington de Abreu; Chaves, Mariana H.

    2007-01-01

    The use of natural products to demonstrate the silica gel column chromatography technique is proposed in the present article. It describes the separation of the triterpenes α- and β-amirin from the diol breine and maniladiol, obtained from almecega resin (Protium heptaphyllum March.). The experiment uses an accessible material, was accomplished in 4 h, and can be applied with success an the experimental course of organic chemistry for undergraduate students. (author)

  19. Terpenos y flavonoides de ageratina fastigiata (H.B.K. King & Robinson

    Directory of Open Access Journals (Sweden)

    Rubén Torrenegra G.

    2010-07-01

    Full Text Available De los extractos lipofílicos tanto de hojas como de flores, se aislaron e identificaron dos derivados del kaurano: el ent-kauran-16B-ol y el entkauran-] 6,20-diol y, dos flavonas metoxiladas: la 5-hidroxi-7,4'-dimetoxiflavona y la 5-hidroxi-3,7,4'-trimetoxi-flavona, Los dos diterpenos confirman la ubicación taxonómica de dicha especie según King y Robinson.

  20. A new one-dimensional NiII coordination polymer with a two-dimensional supramolecular architecture

    Directory of Open Access Journals (Sweden)

    Kai-Long Zhong

    2017-02-01

    Full Text Available A new one-dimensional NiII coordination polymer of 1,3,5-tris(imidazol-1-ylmethylbenzene, namely catena-poly[[aqua(sulfato-κOhemi(μ-ethane-1,2-diol-κ2O:O′[μ3-1,3,5-tris(1H-imidazol-1-ylmethylbenzene-κ3N3,N3′,N3′′]nickel(II] ethane-1,2-diol monosolvate monohydrate], {[Ni(SO4(C18H18N6(C2H6O20.5(H2O]·C2H6O2·H2O}n, was synthesized and characterized by elemental analysis, IR spectroscopy and single-crystal X-ray diffraction. The NiII cation is coordinated by three N atoms of three different 1,3,5-tris(imidazol-1-ylmethylbenzene ligands, one O atom of an ethane-1,2-diol molecule, by a sulfate anion and a water molecule, forming a distorted octahedral NiN3O3 coordination geometry. The tripodal 1,3,5-tris(imidazol-1-ylmethylbenzene ligands link the NiII cations, generating metal–organic chains running along the [100] direction. Adjacent chains are further connected by O—H...O hydrogen bonds, resulting in a two-dimensional supermolecular architecture running parallel to the (001 plane. Another water molecule and a second ethane-1,2-diol molecule are non-coordinating and are linked to the coordinating sulfate ions via O—H...O hydrogen bonds.

  1. The use of stable isotopes and gas chromatography/mass spectrometry in the identification of steroid metabolites in the equine

    International Nuclear Information System (INIS)

    Houghton, E.; Dumasia, M.C.; Teale, P.; Smith, S.J.; Cox, J.; Marshall, D.; Gower, D.B.

    1990-01-01

    Stable isotope gas chromatography/mass spectrometry has been used successfully in the elucidation of structures of urinary steroid metabolites in the horse and in the identification of metabolites isolated from in vivo perfusion and in vitro incubation studies using equine tissue preparations. Deuterium-labeled steroids, testosterone, dehydroepiandrosterone, and 5-androstene-3 beta,17 beta-diol have been synthesized by base-catalyzed isotope exchange methods and the products characterized by gas chromatography/mass spectrometry. [16,16(-2)H2]Dehydroepiandrosterone (plus radiolabeled dehydroepiandrosterone) was perfused into a testicular artery of a pony stallion and was shown to be metabolized into 2H2-labeled testosterone, 4-androstenedione, isomers of 5-androstene-3,17-diol, 19-hydroxytestosterone, and 19-hydroxy-4-androstenedione. In further studies, equine testicular minces have been incubated with 2H2-labeled and radiolabeled dehydroepiandrosterone and 5-androstene-3 beta, 17 beta-diol. The metabolites, whose identity was confirmed by stable isotope gas chromatography/mass spectrometry, proved the interconversion of the two substrates, as well as formation of testosterone and 4-androstenedione. The aromatization of dehydroepiandrosterone was also confirmed, together with the formation of an isomer of 5(10)-estrene-3,17-diol from both substrates showing 19-demethylation without concomitant aromatization. In studies of the feto-placental unit, the allantochorion was shown to aromatize [2H5]testosterone to [2H4]estradiol, the loss of one 2H from the substrate being consistent with aromatization of the A ring. The formation of 6-hydroxyestradiol was also confirmed in this study. The same technique has been valuable in determining the structure of two metabolites of nandrolone isolated from horse urine

  2. TERPENOS Y FLAVONOIDES DE Ageratina fastigiata (H.B.K. King & Robinson

    Directory of Open Access Journals (Sweden)

    Ruben Torrenegra G.

    2010-09-01

    Full Text Available De los extractos lipofílicos tanto de hojas como de flores, se aislaron e identificaron dos derivados del kaurano: el ent-kauran-16B-ol y el entkauran-] 6,20-diol y, dos flavonas metoxiladas: la 5-hidroxi-7,4' dimetoxiflavona y la 5-hidroxi-3,7,4'-trimetoxi-flavona, Los dos diterpenos confirman la ubicación taxonómica de dicha especie según King y Robinson.

  3. A new biphenyl derivative from the mangrove endophytic fungus Phomopsis longicolla HL-2232.

    Science.gov (United States)

    Li, Xiao-Bao; Chen, Guang-Ying; Liu, Rui-Jie; Zheng, Cai-Juan; Song, Xin-Ming; Han, Chang-Ri

    2017-10-01

    A new biphenyl derivative 5,5'-dimethoxybiphenyl-2,2'-diol (1), together with five known compounds (2-5), was isolated from the mangrove endophytic fungus Phomopsis longicolla HL-2232. The structures of these compounds were elucidated using comprehensive spectroscopic methods. The absolute configuration of 4 was determined by single-crystal X-ray diffraction for the first time. The inhibitory activities of all compounds against two Vibrio bacteria were evaluated.

  4. Tools for Chemical Biology: New Macrocyclic Compounds from Diversity-Oriented Synthesis and Toward Materials from Silver(I) Acetylides

    DEFF Research Database (Denmark)

    Madsen, Charlotte Marie

    Part I The formation of a library of diverse macrocyclic compounds with different functionalities and ring sizes in a few steps from two easily accessible α,ω-diol building blocks is presented. The building blocks are combined by esteriffcations in four different ways leading to the formation of ...... of uoro-iodoadamantanes. However, overall the results provide a good starting point for the synthesis of new triptycene and adamantane-containing molecules that can interact with carbon nanotubes....

  5. Propheromones that release pheromonal carbonyl compounds in light.

    Science.gov (United States)

    Liu, X; Macaulay, E D; Pickett, J A

    1984-05-01

    Pheromonal carbonyl compounds; (Z)-11-hexadecanal, (E)-citral, and 2-heptanone were treated with six alcohols to give acetals or ketals, some of which acted as propheromones by releasing the pheromonal carbonyl compounds in ultraviolet or simulated sunlight. Highest yields of pheromone were obtained from adducts prepared witho-nitrobenzyl alcohol ando-nitrophenylethane-1,2-diol. Adducts from (Z)-11-hexadecenal and these two alcohols were employed in lures to catch diamondback moths,Plutella xylostella (L.).

  6. Crystal structure of 2,2′′-bis(2,7-dichloro-9-hydroxy-9H-fluoren-9-yl-1,1′:4′,1′′-terphenyl triethylamine trisolvate

    Directory of Open Access Journals (Sweden)

    Henrik Klien

    2015-12-01

    Full Text Available In the title solvate, C44H26Cl4O2·3C6H15N, the asymmetric part of the unit cell comprises two halves of the diol molecules, 2,2′′-bis(2,7-dichloro-9-hydroxy-9H-fluoren-9-yl-1,1′:4′,1′′-terphenyl, and three molecules of triethylamine, i. e. the diol molecules are located on crystallographic symmetry centres. Two of the solvent molecules are disordered over two positions [occupancy ratios of 0.567 (3:0.433 (3 and 0.503 (3:0.497 (3]. In the diol molecules, the outer rings of the 1,1′:4′,1′′-terphenyl elements are twisted with reference to their central arene ring and the mean planes of the fluorenyl moieties are inclined with respect to the terphenyl ring to which they are connected, the latter making dihedral angles of 82.05 (8 and 82.28 (8°. The presence of two 9-fluoren-9-ol units attached at positions 2 and 2′′ of the terphenyl moiety induces a `folded' geometry which is stabilized by intramolecular C—H...O hydrogen bonds and π–π stacking interactions, the latter formed between the fluorenyl units and the central ring of the terphenyl unit [centroid–centroid distances = 3.559 (1 and 3.562 (1 Å]. The crystal is composed of 1:2 complex units, in which the solvent molecules are associated with the diol molecules via O—H...N hydrogen bonds, while the remaining solvent molecule is linked to the host by a C—H...N hydrogen bond. The given pattern of intermolecular interactions results in formation of chain structures extending along [010].

  7. Three new drimane sesquiterpenoids from cultures of the fungus Penicillium sp.

    Science.gov (United States)

    Ding, Jian-Hai; Ding, Zhang-Gui; Chunyu, Wei-Xun; Zhao, Jiang-Yuan; Wang, Hai-Bin; Liu, Shi-Wei; Wang, Fei

    2017-08-01

    Three new drimane sesquiterpenoids, 12-hydroxyalbrassitriol (1), drim-8(12)-en-6β,7α, 9α,11-tetraol (2), and drim-68(12)-dien-9α,11-diol (3), along with one known analog albrassitriol (4), were isolated from cultures of the tin mine tailings-associated fungus Penicillium sp. The new structures were determined on the basis of extensive spectroscopic analyses. All compounds were tested for their cytotoxicities against five human cancer cell lines.

  8. Preparation of dual-responsive hybrid fluorescent nano probe based on graphene oxide and boronic acid/BODIPY-conjugated polymer for cell imaging

    Energy Technology Data Exchange (ETDEWEB)

    Khoerunnisa [Department of IT Convergence, Korea National University of Transportation, Chungju 380–702 (Korea, Republic of); Kang, Eun Bi [Department of Chemical and Biological Engineering, Korea National University of Transportation, Chungju 380–702 (Korea, Republic of); Mazrad, Zihnil Adha Islamy [Department of IT Convergence, Korea National University of Transportation, Chungju 380–702 (Korea, Republic of); Lee, Gibaek [Department of Chemical and Biological Engineering, Korea National University of Transportation, Chungju 380–702 (Korea, Republic of); In, Insik [Department of IT Convergence, Korea National University of Transportation, Chungju 380–702 (Korea, Republic of); Department of Polymer Science and Engineering, Korea National University of Transportation, Chungju 380–702 (Korea, Republic of); Park, Sung Young, E-mail: parkchem@ut.ac.kr [Department of IT Convergence, Korea National University of Transportation, Chungju 380–702 (Korea, Republic of); Department of Chemical and Biological Engineering, Korea National University of Transportation, Chungju 380–702 (Korea, Republic of)

    2017-02-01

    Here, we report a pH- and thermo-responsive fluorescent nanomaterial of functionalized reduced graphene oxide (rGO) with cross-linked polymer produced via catechol-boronate diol binding mechanism. When conjugated with the hydrophobic dye boron dipyrromethane (BODIPY), this material can act as a dual-responsive nanoplatform for cells imaging. 2-Chloro-3′,4′-dihydroxyacetophenone (CCDP)-quaternized-poly(dimethylaminoethyl methacrylate-co-N-isopropylacrylamide) [C-PDN] was cross-linked with BODIPY and 4-chlorophenyl boronic acid (BA)-quaternized-poly(ethylene glycol)-g-poly(dimethylaminoethyl methacrylate-co-N-isopropylacrylamide) [BB-PPDN]. The GO was then reduced by the catechol group in the cross-linked polymer to synthesize rGO nanoparticles, which able to stabilize the quenching mechanism. This nanoplatform exhibits intense fluorescence at acidic pH and low fluorescence at physiological pH. Confocal laser scanning microscopy (CLSM) images shows bright fluorescence at lysosomal pH and total quench at physiological pH. Therefore, we have successfully developed a promising sensitive bio-imaging probe for identifying cancer cells. - Graphical abstract: [BB-PPDN]-[C-PDN]/rGO nanoparticles with boronic acid-catechol cis-diol binding mechanism toward change in pH demonstrated good biocompatibility and effective quenching for cancer cell detection. - Highlights: • Dual responsive (pH- and thermo) fluorescent nano probe was proposed for cells imaging. • The mechanism was based on cis-diol binding mechanism of boronic acid and catechol. • Reduced graphene oxide was used as quencher on nano-platform. • Detection was controlled dependent on pH based on diol compound of boron chemistry.

  9. Preparation and characterization of polyurethane - Fe powder composites

    Czech Academy of Sciences Publication Activity Database

    Špírková, Milena; Bureš, R.; Fáberová, M.; Trchová, Miroslava; Strachota, Adam; Kaprálková, Ludmila

    2011-01-01

    Roč. 11, 3/4 (2011), s. 290-299 ISSN 1335-8987 R&D Projects: GA ČR GAP108/10/0195 Institutional research plan: CEZ:AV0Z40500505 Keywords : polyurethanes * polybutadiene diol * Fe powder Subject RIV: CD - Macromolecular Chemistry http://www.imr.saske.sk/pmp/issue/3-4-2011/PMP_Vol11_No3-4_p_290-299.pdf

  10. [New cerebroside from leaves of pineapple].

    Science.gov (United States)

    Wang, Jin-Ping; Wang, Hong-Ying; Du, Li-Jun; Ding, Yi; Xing, Dong-Ming; Wang, Wei

    2007-03-01

    To study the chemical constituents of the leaves of pineapple. Chromatographic methods were used to isolate compounds from the leaves of pineapple and spectral methods were used to identify the structures of the isolated compounds. Compound 1 was isolated from the leaves of pineapple. It was identified as 1-O-beta-D-glucopyranosyl-(2S, 3R, 4E, 11E)-2-[(2(R)-hydroxydocosanoyl) amido]-4, 11-hexadecanediene-1, 3-diol. Compound 1 was a new compound.

  11. Assessment of PAH-exposure among coke oven workers

    Energy Technology Data Exchange (ETDEWEB)

    Vahakangas, K. [and others] [Oulu University, Oulu (Finland)

    1992-12-31

    Levels of BaP diol epoxide - DNA adducts in urine and blood were monitored for workers at the Raahe coking plant, Finland, and other relevant information was collected. All adduct values were low, but oven battery workers had slightly higher values than matched controls. Antibodies to these adducts increased somewhat after work at the plant started, no differences between smokers and non-smokers were found.

  12. Total syntheses of Prelactone V and Prelactone B.

    Science.gov (United States)

    Raghavendra, S; Tadiparthi, Krishnaji; Yadav, J S

    2017-04-10

    The total syntheses of natural products Prelactone-V and Prelactone-B have been accomplished by a novel Chiron approach starting from d-glucose. The synthesis involves isopropylidene acetal formation of d-glucose using Poly(4-vinylpyridine) supported iodine as a catalyst, Tebbe olefination, Grignard reaction, Wittig olefination, selective mono deprotection of acetal using PMA/SiO 2 , hydrogenation and anti-1,3-diol formation are as key steps. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Isolation of Triterpenoid Glycoside from Bark of Terminalia arjuna using Chromatographic Technique and Investigation of Pharmacological Behavior upon Muscle Tissues

    Directory of Open Access Journals (Sweden)

    Tanushree Patnaik

    2007-01-01

    Full Text Available This study reports the isolation and characterization of a new triterpenoid glycoside extracted from the bark of Terminalia arjuna. The isolation of the organic compounds was done using simple chromatographic technique. Compound characterization using various spectroscopic technique identify the final isolated compound as Olean-3β,22β-diol-12-en-28β-D-glucopyranoside-oic acid. The method of isolation is simple, cost effective and efficient. The preliminary bioactivity of the compound was also evaluated.

  14. Stability of biodegradable waterborne polyurethane films in buffered saline solutions.

    Science.gov (United States)

    Lin, Ying Yi; Hung, Kun-Che; Hsu, Shan-Hui

    2015-09-21

    The stability of polyurethane (PU) is of critical importance for applications such as in coating industry or as biomaterials. To eliminate the environmental concerns on the synthesis of PU which involves the use of organic solvents, the aqueous-based or waterborne PU (WBPU) has been developed. WBPU, however, may be unstable in an electrolyte-rich environment. In this study, the authors reported the stability of biodegradable WBPU in the buffered saline solutions evaluated by atomic force microscopy (AFM). Various biodegradable WBPU films were prepared by spin coating on coverslip glass, with a thickness of ∼300 nm. The surface AFM images of poly(ε-caprolactone) (PCL) diol-based WBPU revealed nanoglobular structure. The same feature was observed when 20% molar of the PCL diol soft segment was replaced by polyethylene butylenes adipate diol. After hydration in buffered saline solutions for 24 h, the surface domains generally increased in sizes and became irregular in shape. On the other hand, when the soft segment was replaced by 20% poly(l-lactide) diol, a meshlike surface structure was demonstrated by AFM. When the latter WBPU was hydrated, the surface domains appeared to be disconnected. Results from the attenuated total reflectance infrared spectroscopy and x-ray photoelectron spectroscopy indicated that the surface chemistry of WBPU films was altered after hydration. These changes were probably associated with the neutralization of carboxylate by ions in the saline solutions, resulting in the rearrangements of soft and hard segments and causing instability of the WBPU.

  15. Identification of In-Chain-Functionalized Compounds and Methyl-Branched Alkanes in Cuticular Waxes of Triticum aestivum cv. Bethlehem.

    Directory of Open Access Journals (Sweden)

    Radu C Racovita

    Full Text Available In this work, cuticular waxes from flag leaf blades and peduncles of Triticum aestivum cv. Bethlehem were investigated in search for novel wax compounds. Seven wax compound classes were detected that had previously not been reported, and their structures were elucidated using gas chromatography-mass spectrometry of various derivatives. Six of the classes were identified as series of homologs differing by two methylene units, while the seventh was a homologous series with homologs with single methylene unit differences. In the waxes of flag leaf blades, secondary alcohols (predominantly C27 and C33, primary/secondary diols (predominantly C28 and esters of primary/secondary diols (predominantly C50, combining C28 diol with C22 acid were found, all sharing similar secondary hydroxyl group positions at and around C-12 or ω-12. 7- and 8-hydroxy-2-alkanol esters (predominantly C35, 7- and 8-oxo-2-alkanol esters (predominantly C35, and 4-alkylbutan-4-olides (predominantly C28 were found both in flag leaf and peduncle wax mixtures. Finally, a series of even- and odd-numbered alkane homologs was identified in both leaf and peduncle waxes, with an internal methyl branch preferentially on C-11 and C-13 of homologs with even total carbon number and on C-12 of odd-numbered homologs. Biosynthetic pathways are suggested for all compounds, based on common structural features and matching chain length profiles with other wheat wax compound classes.

  16. Trachylobane and kaurane diterpenes from Croton floribundus spreng

    Energy Technology Data Exchange (ETDEWEB)

    Uchoa, Paula Karina S.; Silva Junior, Jose Nunes da; Silveira, Edilberto Rocha; Lima, Mary Anne S., E-mail: mary@dqoi.ufc.br [Departamento de Quimica Organica e Inorganica, Centro de Ciencias, Universidade Federal do Ceara, Fortaleza, CE (Brazil); Braz-Filho, Raimundo [Laboratorio de Ciencias Quimicas, Centro de Ciencias Tecnologicas, Universidade Estadual do Norte Fluminense, Campo dos Goytacazes, RJ (Brazil); Costa-Lotufo, Leticia Veras; Araujo, Ana Jersia; Moraes, Manoel Odorico de; Pessoa, Claudia do O [Departamento de Farmacologia e Fisiologia, Centro de Ciencias da Saude, Universidade Federal do Ceara, Fortaleza, CE (Brazil)

    2013-09-01

    A new trachylobane diterpene ent-trachyloban-18,19-diol (1) was isolated from root bark of Croton floribundus, along with known diterpenes ent-trachyloban-19-oic acid (2), 15{beta}-hydroxy-ent-trachyloban-19-oic acid (3), ent-trachyloban-19-ol (4), ent-kaur-16-en-19-oic acid (5), ent-kaur-16-ene-6{alpha},19-diol (6) and ent-16{alpha}-hydroxykaur-11-en-19-oic acid (7). ent-trachyloban-18,19-diol (1) was submitted to derivatization reactions affording four new compounds (8-11). Cytotoxic activity of diterpenes 1, 3, 4, 7-11 against three human cancer cell lines was evaluated. No compounds showed cytotoxic potential with IC{sub 50} values greater than 25 {mu}g/mL. Compound 6 was evaluated against five human cancer cell lines, showing moderate effect against three cancer cell lines, MDA-MB-435, HCT-8 and HCT-116, with IC{sub 50} values of 14.32, 13.47 and 12.1 {mu}g/mL, respectively. (author)

  17. Increased 5α-reductase activity in idiopathic hirsutism

    International Nuclear Information System (INIS)

    Serafini, P.; Lobo, R.A.

    1985-01-01

    In vitro, genital skin 5α-reductase activity (5α-RA) was measured in ten hirsute women with normal androgen levels (idiopathic hirsutism (IH)) and in ten hirsute women with elevated androgen levels (polycystic ovary syndrome (PCO)) in order to determine the influence of secreted androgens on 5α-RA. In vitro 5α-RA was assessed by incubations of skin with 14 C-testosterone (T) for 2 hours, after which steroids were separated and the radioactivity of dihydrotestosterone (DHT) and 5α-androstane 3α-17β-estradiol (3α-diol) in specific eluates were determined. All androgens were normal in IH with the exception of higher levels of 3α-diol glucuronide which were similar to the levels of PCO. The conversion ratio (CR) of T to DHT in IH and PCO were similar, yet significantly greater than the CR of control subjects. The CR of T to 3α-diol in IH and PCO were similar, yet higher than in control subjects. Serum androgens showed no correlation with 5α-RA, while the CR of T to DHT showed a significant positive correlation with the Ferriman and Gallwey score. The increased 5α-RA in IH appears to be independent of serum androgen levels and is, therefore, an inherent abnormality. The term idiopathic is a misnomer, because hirsutism in these patients may be explained on the basis of increased skin 5α-RA

  18. Biotransformation of limonene by an endophytic fungus using synthetic and orange residue-based media.

    Science.gov (United States)

    Bier, Mário Cesar Jucoski; Medeiros, Adriane Bianchi Pedroni; Soccol, Carlos Ricardo

    2017-02-01

    Aroma and fragrances have high commercial value for use in food, cosmetics and perfumes. The biotransformation of terpenes by microorganisms represents an attractive alternative method for production of flavourings. Endophytic fungi offer a great potential for the production of several groups of compounds; however, few studies have evaluated the biotransformation of limonene. Following preliminary studies on the biotransformation of limonene, submerged fermentation was carried out using an endophytic fungus isolated from Pinus taeda and identified as Phomopsis sp. The presence of several biotransformation products was detected and identified by mass spectrometry (GC-MS). The studied strain showed a divergent metabolic behaviour, as compounds of interest such as α-terpineol, carvone, and limoneno-1,2-diol were produced under different conditions. In addition to the minor metabolites terpinen-4-ol, menthol and carveol, this strain also produced major metabolites, including 0.536 g L -1 carvone and 2.08 g L -1 limonene-1,2-diol in synthetic medium and 2.10 g L -1 limonene-1,2-diol in a natural orange extract medium with single fed-batch, while the cyclic fed-batch resulted in concentrations less than 1 g L -1 . Therefore, our study produced a wide variety of limonene derivatives at a high concentration using a natural medium and a newly isolated endophytic fungal strain. Copyright © 2016 British Mycological Society. Published by Elsevier Ltd. All rights reserved.

  19. Synthesis of three bromophenols from red algae as PTP1B inhibitors

    Science.gov (United States)

    Guo, Shuju; Li, Jing; Li, Ting; Shi, Dayong; Han, Lijun

    2011-01-01

    Bromophenols are a set of natural products widely distributed in seaweed, most of which exhibit interesting and useful biological activities. To develop a reliable and efficient synthetic route to these natural bromophenols, three of them, 3,4-dibromo-5-(2'-bromo-3',4'-dihydroxy-6'-methoxymethyl-benzyl)-benzene-1,2-diol (compound 9), 3,4-dibromo-5-(2'-bromo-6'-ethoxy methyl-3',4'-dihydroxybenzyl)-benzene-1,2-diol (compound 10), and 3-bromo-4-(3'-bromo-4',5'-dihydroxy benzyl)-5-(ethoxymethyl)-benzene-1,2-diol (compound 14), isolated from red marine algae, have been synthesized in eight steps with an overall yield of 14.4%, 14.4%, and 18.2% respectively, via a practical approach employing bromination, Wolff-Kishner-Huang reduction and a Friedel-Crafts reaction as key steps. The protein tyrosine phosphatase 1B (PTP1B) inhibitory activities of the synthetic compounds were evaluated by the colorimetric assay. The results show that these compounds are moderate PTP1B inhibitors. The synthesis of these bromophenol derivatives makes in vivo studies of their structure-activity relationships and inhibition activity against PTP1B possible.

  20. Synthesis of specifically deuterium-labelled pregnanolone and pregnanediol sulphates for metabolic studies in humans.

    Science.gov (United States)

    Baillie, T A; Sjövall, J; Herz, J E

    1975-10-01

    A synthesis is reported of 3beta-hydroxy-5alpha-pregnan-20-one sulphate and the disulphate and 3-monosulphate of 5alpha-pregnane-3beta,20alpha-diol, labelled specifically with deuterium in high isotopic purity for metabolic studies in humans. Base-catalyzed equilibration of 3beta-hydroxy-5alpha-25R-spirostan-12-one (hemcogenin, II) with deuterium oxide, followed by removal of the 12-keto group and degradation of the sapogenin side-chain afforded 3beta-hydroxy-5alpha-[11,11-2H2]pregn-16-en-20-one (VII). Further deuterium atoms were introduced at the 3alpha and 20beta positions by reductions with sodium borodeuteride and lithium aluminum deuteride, respectively. These reactions led to 3beta-hydroxy-5alpha-[3alpha,11,11-2H3]pregnan-20-one (X; isotopic purity 87.2%) and 5alpha-[3alpha,11,11,20beta-2H4]pregnane-3beta,20alpha-diol (XIV; isotopic purity 83.9%). The 3-sulphate of the pregnanolone and the 3,20-disulphate of the pregnanediol were prepared directly form the free alcohols, while the 3-monosulphate of the pregnanediol was obtained via 5alpha-[3alpha,11,11,20beta-2H4]pregnane-3beta,20alpha-diol 20-acetate (XVII).

  1. An Undergraduate Experiment in Polyester (PET) Synthesis

    Science.gov (United States)

    Cammidge, Andrew N.

    1999-02-01

    The most important polyester manufactured industrially is PET (polyethyleneterephthalate). We describe an experiment that conveniently mimics the industrial synthesis in the undergraduate laboratory. The first step of the reaction is a base-catalyzed transesterification between ethane diol and dimethylterephthalate. Methanol is distilled off to drive the reaction to completion. Excess ethane diol is employed to suppress formation of higher oligomers. The intermediate (bis-(2-hydroxyethyl)terephthalate) is isolated by crystallization and filtration and characterized by 1H NMR spectroscopy. In the second step the monomer is heated (with and without acid catalyst) to form polymer. Samples are removed at intervals and their physical properties are recorded as they cool. These properties are used to qualitatively monitor polymerization. This experiment reinforces some fundamental chemical concepts and introduces the students to new laboratory procedures. The students perform a distillation and apply their knowledge of the reaction equilibrium to calculate the volume of distillate (methanol) expected. The reversible nature of esterification reactions is emphasized during the polymerization step (acid-catalyzed), where the process is driven towards polymer formation by the removal (evaporation) of ethane diol.

  2. Spectrophotometric determination of boric acid in boron powder with curcumin

    International Nuclear Information System (INIS)

    Grotheer, E.W.

    1979-01-01

    A rapid and accurate method was needed to determine trace amounts of boric acid for quality control and specification testing of elemental boron. The reaction between boric acid and curcumin occurs at a measurable rate only when the curcumin molecule is protonated. Protonation takes place at the carbonyl groups in the presence of a strong acid and occurs completely and rapidly when sulfuric acid is added to a solution of curcumin in acetic acid. Spectrophotometric measurements were made. The extraction of boric acid from boron powder was found to be complete within 2h when either water or the diol solution was used. Whatman No. 40 cr 42 filter paper was used to obtain diol samples free of boron particles. The extraction efficiency of 2-ethyl-1,3-hexanediol was evaluated by adding 1 ml of 500 ppM aqueous boric acid and 1 drop of 10% NaOH to accurately weighed samples of boron powder. The water then was evaporated at room temperature and the samples were extracted with diol solution. The data obtained are included. The extraction efficiency also was evaluated by determining the boric acid content of boron which had been recovered from a previous extraction and boric acid determination. The determination of boric acid using curcumin is unaffected by the presence of other compounds, except for fluoride and nitrate ions. 2 tables

  3. A short-term study on the interaction of bacteria, fungi and endosulfan in soil microcosm.

    Science.gov (United States)

    Xie, Huijun; Gao, Fuwei; Tan, Wei; Wang, Shu-Guang

    2011-12-15

    Endosulfan is one of the few organic chlorine insecticides still in use today in many developing countries. It has medium toxicity for fish and aquatic invertebrates. In this study, we added different concentrations of endosulfan to a series of soil samples collected from Baihua Park in Jinan, Shandong Province, China. Interactions of exogenous endosulfan, bacteria and fungi were analyzed by monitoring the changes in microbe-specific phospholipid fatty acids (PLFA), residual endosulfan and its metabolites which include; endosulfan sulfate, endosulfan lactone and endosulfan diol during a 9 days incubation period. Our results showed that endosulfan reduced fungi biomass by 47% on average after 9 days, while bacteria biomass increased 76% on average. In addition, we found that endosulfan degraded 8.62% in natural soil (NE), 5.51% in strepolin soil (SSE) and 2.47% in sterile soil (SE). Further analysis of the endosulfan metabolites in NE and SSE, revealed that the amount of endosulfan sulfate (ES) significantly increased and that of endosulfan lactone (EL) slightly decreased in both samples after 9 days. However, that of endosulfan diol (ED) increased in NE and decreased in SSE. After collective analysis our data demonstrated that fungi and bacteria responded differently to exogeous endosulfan, in a way that could promote the formation of endosulfan diol during endosulfan degradation. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. Fluorometric detection of nitroaromatics by fluorescent lead complexes: A spectroscopic assessment of detection mechanism

    Science.gov (United States)

    Chattopadhyay, Tanmay; Chatterjee, Sourav; Majumder, Ishani; Ghosh, Soumen; Yoon, Sangee; Sim, Eunji

    2018-04-01

    Three Schiff base ligands such as 2-[(2-Hydroxy-3-methoxy-benzylidene)-amino]-2-hydroxymethyl-propane-1,3-diol (HL1), 2-[(2-Hydroxy-benzylidene)-amino]-2-hydroxymethyl-propane-1,3-diol (HL2), 2-[(3,5-Dichloro-2-hydroxy-benzylidene)-amino]-2-hydroxymethyl-propane-1,3-diol (HL3) have been synthesized by condensation of aldehydes (such as 3,5-Dichloro-2-hydroxy benzaldehyde, 2-Hydroxy-benzaldehyde, and 2-Hydroxy-3-methoxy-benzaldehyde) with Tris-(hydroxymethyl)amino methane and characterized by IR, UV-vis and 1H NMR spectroscopy. Then all these three ligands have been used to prepare Pb(II) complexes by reaction with lead(II) acetate tri-hydrate in methanol. In view of analytical and spectral (IR, UV-vis and Mass) studies, it has been concluded that, except HL2, other two ligands form 1:1 metal complexes (1 and 3) with lead. Between two complexes, complex 3 is highly fluorescent and this property has been used to identify the pollutant nitroaromatics. Finally, the quenching mechanism has been established by means of spectroscopic investigation.

  5. Binary boronic acid-functionalized attapulgite with high adsorption capacity for selective capture of nucleosides at acidic pH values

    International Nuclear Information System (INIS)

    Li, Huihui; Zhu, Shuqiang; Cheng, Ting; Wang, Shuxia; Zhu, Bin; Liu, Xiaoyan; Zhang, Haixia

    2016-01-01

    Boronate affinity materials have been widely used for selective capture of cis-diols such as nucleosides. Adsorbents with features of low binding pH and high adsorption capacity are highly desired. However, most reported materials only possess one of the two features. We have synthesized a 1,3,5-triazine-containing binary boronic acid by reacting cyanuric chloride with 3-amino phenylboronic acid, and the product was then grafted onto attapulgite (a fibrous aluminum-magnesium silicate). The resulting functionalized attapulgite exhibit low binding pH (5.0) and display high adsorption capacity (19.5 ± 1.1 mg⋅g"−"1 for adenosine). The material exhibits high selectivity for cis-diols even in the presence of a 1000-fold excess of interferences. It was applied to the selective extraction of nucleosides from human urine. Typical features of the method include (a) limits of detection in the range from 4 to 17 ng⋅mL"−"1, (b) limits of quantification between 13 and 57 ng⋅mL"−"1, (c) relative standard deviations of ≤9.1 %, and (d) recoveries of nucleosides from spiked human urine between 85.0 and 112.9 %. In our perception, the material and method offer a promising strategy for selective capture of cis-diols in the areas of proteomics, metabolomics and glycomics. (author)

  6. The effect of cell immobilization on the antibacterial activity of Lactobacillus reuteri DPC16 cells during passage through a simulated gastrointestinal tract system.

    Science.gov (United States)

    Zhao, Qian; Maddox, Ian S; Mutukumira, Anthony; Lee, Sung Je; Shu, Quan

    2012-10-01

    Cell immobilization has the ability to influence the survival and functional characteristics of probiotic bacterial strains in harsh environments. This study investigated the effect of cell immobilization and passage through a simulated gastrointestinal tract (GI) on the antibacterial activity of Lactobacillus reuteri DPC16. Antibacterial activity, reuterin production and diol dehydratase activity were assayed in recovered isolates of L. reuteri that had been immobilized in Ca alginate-skim milk, and incubated in simulated GI fluids. Among all the recovered isolates tested, any that had undergone immobilization followed by immediate recovery of the cells without subsequent incubation in any fluids demonstrated the highest reuterin production, antimicrobial activity and diol dehydratase enzyme activity. L. reuteri DPC16 cells that had been immobilized, incubated in simulated GI fluids, and subsequently recovered from the beads often showed some loss of antimicrobial activity compared to the immobilized cells. The data confirm that the process of immobilization of L. reuteri in Ca alginate-skim milk, rather than the passage through simulated GI fluids, resulted in enhanced antibacterial activity. This is attributed to increased diol dehydratase activity, resulting in increased reuterin production.

  7. Composition of secondary alcohols, ketones, alkanediols, and ketols in Arabidopsis thaliana cuticular waxes

    Science.gov (United States)

    Wen, Miao; Jetter, Reinhard

    2009-01-01

    Arabidopsis wax components containing secondary functional groups were examined (i) to test the biosynthetic relationship between secondary alcohols and ketols and (ii) to determine the regiospecificity and substrate preference of the enzyme involved in ketol biosynthesis. The stem wax of Arabidopsis wild type contained homologous series of C27 to C31 secondary alcohols (2.4 μg cm−2) and C28 to C30 ketones (6.0 μg cm−2) dominated by C29 homologues. In addition, compound classes containing two secondary functional groups were identified as C29 diols (∼0.05 μg cm−2) and ketols (∼0.16 μg cm−2). All four compound classes showed characteristic isomer distributions, with functional groups located between C-14 and C-16. In the mah1 mutant stem wax, diols and ketols could not be detected, while the amounts of secondary alcohols and ketones were drastically reduced. In two MAH1-overexpressing lines, equal amounts of C29 and C31 secondary alcohols were detected. Based on the comparison of homologue and isomer compositions between the different genotypes, it can be concluded that biosynthetic pathways lead from alkanes to secondary alcohols, and via ketones or diols to ketols. It seems plausible that MAH1 is the hydroxylase enzyme involved in all these conversions in Arabidopsis thaliana. PMID:19346242

  8. Catalyst Influence on Undesired Side Reactions in the Polycondensation of Fully Bio-Based Polyester Itaconates

    Directory of Open Access Journals (Sweden)

    Ina Schoon

    2017-12-01

    Full Text Available Bio-based unsaturated polyester resins derived from itaconic acid can be an alternative to established resins of this type in the field of radical-curing resins. However, one of the challenges of these polyester itaconates is the somewhat more elaborate synthetic process, especially under polycondensation conditions used on an industrial scale. The α,β-unsaturated double bond of the itaconic acid is prone to side reactions that can lead to the gelation of the polyester resin under standard conditions. This is especially true when bio-based diols such as 1,3-propanediol or 1,4-butanediol are used to obtain resins that are 100% derived from renewable resources. It was observed in earlier studies that high amounts of these aliphatic diols in the polyester lead to low conversion and gelation of the resins. In this work, a catalytic study using different diols was performed in order to elucidate the reasons for this behavior. It was shown that the choice of catalyst has a crucial influence on the side reactions occurring during the polycondensation reactions. In addition, the side reactions taking place were identified and suppressed. These results will allow for the synthesis of polyester itaconates on a larger scale, setting the stage for their industrial application.

  9. Environmentally-Friendly Synthesis of Carbonate-Type Macrodiols and Preparation of Transparent Self-Healable Thermoplastic Polyurethanes

    Directory of Open Access Journals (Sweden)

    Seon-Mi Kim

    2017-11-01

    Full Text Available Carbonate-type macrodiols synthesized by base-catalyzed polycondensation of co-diols and dimethyl carbonate as an environmentally-friendly route were subsequently utilized for the preparation of transparent and self-healable thermoplastic polyurethanes (TPUs containing a carbonate-type soft segment. Three types of macrodiols, obtained from mono, dual and triple diol-monomers for target molecular weights of 1 and 1.5 kg mol−1, were analyzed by 1H NMR integration and the OH titration value. Colorless transparent macrodiols in a liquid state at a room temperature of 20 °C were obtained, except the macrodiol from mono 1,6-hexanediol. Before TPU synthesis, macrodiols require pH neutralization to prevent gelation. TPUs synthesized by a solution pre-polymer method with 4,4′-methylene(bisphenyl isocyanate and 1,4-butanediol as a chain extender exhibited moderate molecular weights, good transparencies and robust mechanical properties. Especially, the incorporation of 3-methyl-1,5-pentanediol within carbonate-type macrodiols enhanced the transparency of the resultant TPUs by decreasing the degree of microphase separation evidenced by ATR-FTIR and DSC. Interestingly, packing density of hard segments and the degree of microphase separation determined the self-healing efficiency of TPUs, which showed good performances in the case of sourced macrodiols from triple diol-monomers.

  10. Trachylobane and kaurane diterpenes from Croton floribundus spreng

    International Nuclear Information System (INIS)

    Uchôa, Paula Karina S.; Silva Junior, José Nunes da; Silveira, Edilberto Rocha; Lima, Mary Anne S.; Braz-Filho, Raimundo; Costa-Lotufo, Letícia Veras; Araújo, Ana Jérsia; Moraes, Manoel Odorico de; Pessoa, Claudia do Ó

    2013-01-01

    A new trachylobane diterpene ent-trachyloban-18,19-diol (1) was isolated from root bark of Croton floribundus, along with known diterpenes ent-trachyloban-19-oic acid (2), 15β-hydroxy-ent-trachyloban-19-oic acid (3), ent-trachyloban-19-ol (4), ent-kaur-16-en-19-oic acid (5), ent-kaur-16-ene-6α,19-diol (6) and ent-16α-hydroxykaur-11-en-19-oic acid (7). ent-trachyloban-18,19-diol (1) was submitted to derivatization reactions affording four new compounds (8-11). Cytotoxic activity of diterpenes 1, 3, 4, 7-11 against three human cancer cell lines was evaluated. No compounds showed cytotoxic potential with IC 50 values greater than 25 μg/mL. Compound 6 was evaluated against five human cancer cell lines, showing moderate effect against three cancer cell lines, MDA-MB-435, HCT-8 and HCT-116, with IC 50 values of 14.32, 13.47 and 12.1 μg/mL, respectively. (author)

  11. Characterization of 17α-hydroxysteroid dehydrogenase activity (17α-HSD and its involvement in the biosynthesis of epitestosterone

    Directory of Open Access Journals (Sweden)

    Breton Rock

    2005-07-01

    Full Text Available Abstract Background Epi-testosterone (epiT is the 17α-epimer of testosterone. It has been found at similar level as testosterone in human biological fluids. This steroid has thus been used as a natural internal standard for assessing testosterone abuse in sports. EpiT has been also shown to accumulate in mammary cyst fluid and in human prostate. It was found to possess antiandrogenic activity as well as neuroprotective effects. So far, the exact pathway leading to the formation of epiT has not been elucidated. Results In this report, we describe the isolation and characterization of the enzyme 17α-hydroxysteroid dehydrogenase. The name is given according to its most potent activity. Using cells stably expressing the enzyme, we show that 17α-HSD catalyzes efficienty the transformation of 4-androstenedione (4-dione, dehydroepiandrosterone (DHEA, 5α-androstane-3,17-dione (5α-dione and androsterone (ADT into their corresponding 17α-hydroxy-steroids : epiT, 5-androstene-3β,17α-diol (epi5diol, 5α-androstane-17α-ol-3-one (epiDHT and 5α-androstane-3α,17α-diol (epi3α-diol, respectively. Similar to other members of the aldo-keto reductase family that possess the ability to reduce the keto-group into hydroxyl-group at different position on the steroid nucleus, 17α-HSD could also catalyze the transformation of DHT, 5α-dione, and 5α-pregnane-3,20-dione (DHP into 3α-diol, ADT and 5α-pregnane-3α-ol-20-one (allopregnanolone through its less potent 3α-HSD activity. We also have over-expressed the 17α-HSD in Escherichia coli and have purified it by affinity chromatography. The purified enzyme exhibits the same catalytic properties that have been observed with cultured HEK-293 stably transfected cells. Using quantitative Realtime-PCR to study tissue distribution of this enzyme in the mouse, we observed that it is expressed at very high levels in the kidney. Conclusion The present study permits to clarify the biosynthesis pathway of epiT. It

  12. Generation and characterization of epoxide hydrolase 3 (EPHX3-deficient mice.

    Directory of Open Access Journals (Sweden)

    Samantha L Hoopes

    Full Text Available Cytochrome P450 (CYP epoxygenases metabolize arachidonic acid into epoxyeicosatrienoic acids (EETs, which play an important role in blood pressure regulation, protection against ischemia-reperfusion injury, angiogenesis, and inflammation. Epoxide hydrolases metabolize EETs to their corresponding diols (dihydroxyeicosatrienoic acids; DHETs which are biologically less active. Microsomal epoxide hydrolase (EPHX1, mEH and soluble epoxide hydrolase (EPHX2, sEH were identified >30 years ago and are capable of hydrolyzing EETs to DHETs. A novel epoxide hydrolase, EPHX3, was recently identified by sequence homology and also exhibits epoxide hydrolase activity in vitro with a substrate preference for 9,10-epoxyoctadecamonoenoic acid (EpOME and 11,12-EET. EPHX3 is highly expressed in the skin, lung, stomach, esophagus, and tongue; however, its endogenous function is unknown. Therefore, we investigated the impact of genetic disruption of Ephx3 on fatty acid epoxide hydrolysis and EET-related physiology in mice. Ephx3-/- mice were generated by excising the promoter and first four exons of the Ephx3 gene using Cre-LoxP methodology. LC-MS/MS analysis of Ephx3-/- heart, lung, and skin lysates revealed no differences in endogenous epoxide:diol ratios compared to wild type (WT. Ephx3-/- mice also exhibited no change in plasma levels of fatty acid epoxides and diols relative to WT. Incubations of cytosolic and microsomal fractions prepared from Ephx3-/- and WT stomach, lung, and skin with synthetic 8,9-EET, 11,12-EET, and 9,10-EpOME revealed no significant differences in rates of fatty acid diol formation between the genotypes. Ephx3-/- hearts had similar functional recovery compared to WT hearts following ischemia/reperfusion injury. Following intranasal lipopolysaccharide (LPS exposure, Ephx3-/- mice were not different from WT in terms of lung histology, bronchoalveolar lavage fluid cell counts, or fatty acid epoxide and diol levels. We conclude that genetic

  13. Overexpression of Catalase Enhances Benzo(a)pyrene Detoxification in Endothelial Microsomes.

    Science.gov (United States)

    Yang, Fang; Yang, Hong; Ramesh, Aramandla; Goodwin, J Shawn; Okoro, Emmanuel U; Guo, ZhongMao

    2016-01-01

    We previously reported that overexpression of catalase upregulated xenobiotic- metabolizing enzyme (XME) expression and diminished benzo(a)pyrene (BaP) intermediate accumulation in mouse aortic endothelial cells (MAECs). Endoplasmic reticulum (ER) is the most active organelle involved in BaP metabolism. To examine the involvement of ER in catalase-induced BaP detoxification, we compared the level and distribution of XMEs, and the profile of BaP intermediates in the microsomes of wild-type and catalase transgenic endothelial cells. Our data showed that endothelial microsomes were enriched in cytochrome P450 (CYP) 1A1, CYP1B1 and epoxide hydrolase 1 (EH1), and contained considerable levels of quinone oxidoreductase-1 (NQO1) and glutathione S-transferase-pi (GSTP). Treatment of wild-type MAECs with 1μM BaP for 2 h increased the expression of microsomal CYP1A1, 1B1 and NQO1 by ~300, 64 and 116%, respectively. However, the same treatment did not significantly alter the expression of EH1 and GSTP. Overexpression of catalase did not significantly increase EH1, but upregulated BaP-induced expression of microsomal CYP1A1, 1B1, NQO1 and GSTP in the following order: 1A1>NQO1>GSTP>1B1. Overexpression of catalase did not alter the distribution of each of these enzymes in the microsomes. In contrast to our previous report showing lower level of BaP phenols versus BaP diols/diones in the whole-cell, this report demonstrated that the sum of microsomal BaP phenolic metabolites were ~60% greater than that of the BaP diols/diones after exposure of microsomes to BaP. Overexpression of catalase reduced the concentrations of microsomal BaP phenols and diols/diones by ~45 and 95%, respectively. This process enhanced the ratio of BaP phenol versus diol/dione metabolites in a potent manner. Taken together, upregulation of phase II XMEs and CYP1 proteins, but not EH1 in the ER might be the mechanism by which overexpression of catalase reduces the levels of all the BaP metabolites, and

  14. Group 4 Metalloporphyrin diolato Complexes and Catalytic Application of Metalloporphyrins and Related Transition Metal Complexes

    Energy Technology Data Exchange (ETDEWEB)

    Du, Guodong [Iowa State Univ., Ames, IA (United States)

    2003-01-01

    In this work, the first examples of group 4 metalloporphyrin 1,2-diolato complexes were synthesized through a number of strategies. In general, treatment of imido metalloporphyrin complexes, (TTP)M=NR, (M = Ti, Zr, Hf), with vicinal diols led to the formation of a series of diolato complexes. Alternatively, the chelating pinacolate complexes could be prepared by metathesis of (TTP)MCl2 (M = Ti, Hf) with disodium pinacolate. These complexes were found to undergo C-C cleavage reactions to produce organic carbonyl compounds. For titanium porphyrins, treatment of a titanium(II) alkyne adduct, (TTP)Ti(η2-PhC≡CPh), with aromatic aldehydes or aryl ketones resulted in reductive coupling of the carbonyl groups to produce the corresponding diolato complexes. Aliphatic aldehydes or ketones were not reactive towards (TTP)Ti(η2-PhC≡CPh). However, these carbonyl compounds could be incorporated into a diolato complex on reaction with a reactive precursor, (TTP)Ti[O(Ph)2C(Ph)2O] to provide unsymmetrical diolato complexes via cross coupling reactions. In addition, an enediolato complex (TTP)Ti(OCPhCPhO) was obtained from the reaction of (TTP)Ti(η2-PhC≡CPh) with benzoin. Titanium porphyrin diolato complexes were found to be intermediates in the (TTP)Ti=O-catalyzed cleavage reactions of vicinal diols, in which atmospheric oxygen was the oxidant. Furthermore, (TTP)Ti=O was capable of catalyzing the oxidation of benzyl alcohol and α-hydroxy ketones to benzaldehyde and α-diketones, respectively. Other high valent metalloporphyrin complexes also can catalyze the oxidative diol cleavage and the benzyl alcohol oxidation reactions with dioxygen. A comparison of Ti(IV) and Sn(IV) porphyrin chemistry was undertaken. While chelated diolato complexes were invariably obtained for titanium porphyrins on treatment with 1,2-diols, the reaction of vicinal diols with tin porphyrins gave a number of products, including mono

  15. Cogeneration of electricity and organic chemicals using a polymer electrolyte fuel cell

    International Nuclear Information System (INIS)

    Yuan, X.; Ma, Z.; Bueb, H.; Drillet, J.-F.; Hagen, J.; Schmidt, V.M.

    2005-01-01

    Several unsaturated organic alcohols (allyl alcohol, propargyl alcohol, 2-butin-1,4-diol, 2- buten-1,4-diol) and acids (maleic acid, acrylic acid, crotonic acid, acetylendicarboxylic acid) were used as oxidants together with hydrogen as fuel in a polymer electrolyte fuel cell (PEFC). The standard free enthalpies (Δ R G θ ) of the overall fuel cell reactions H 2 /oxidant were calculated to be negative and the equilibrium voltages of such systems are in the range of U 00 = 0.4-0.6 V. In this way, the cogeneration of electric energy and desired hydrogenated products in a fuel cell reactor is apparent. Nafion[reg] 117, as polymer electrolyte, and commercial gas diffusion electrodes (ETEK) with carbon supported Pt were used in a PEFC reactor. The aqueous solutions of unsaturated alcohols and organic acids (c = 1-2 mol dm -3 ) were pumped under ambient pressure through the cathode compartment of the cell whereas hydrogen was fed into the cell at p 0.15 MPa. The open circuit voltages were measured to be in the range of 0.1-0.25 V. Current densities up to 50 mA cm -2 and maximum power densities of around 1 mW cm -2 has been achieved in the case of allyl alcohol, 2-butene-1,4-diol and acrylic acid. HPLC analysis indicates that the double or triple bond in unsaturated alcohols and organic acids is selectively hydrogenated. In addition, the electrochemical behaviour of the alcohols and acids was studied by means of cyclic voltammetry at a smooth polycrystalline Pt electrode in H 2 SO 4 . Reduction reactions were observed at potentials of E < 200 mV versus RHE. It was found that the onset potential for electrochemical hydrogenation of the double and triple bond in the cyclic voltamogram correlates well with the fuel cell performances using these compounds as oxidants

  16. Selective reduction of AKR1C2 in prostate cancer and its role in DHT metabolism.

    Science.gov (United States)

    Ji, Qing; Chang, Lilly; VanDenBerg, David; Stanczyk, Frank Z; Stolz, Andrew

    2003-03-01

    As androgens play an essential role in prostate cancer, we sought to develop a real-time PCR to characterize mRNA expression profiles of human members of the Aldo-Keto Reductase (AKR) 1C gene family, as well as of 5 alpha-steroid reductase Type II (SRD5A2) in prostate cancer samples. Functional activity and regulation of AKR1C2, a 3 alpha-hydroxysteroid dehydrogenase (HSD) type III, was also assessed in prostate cancer cell lines. Gene specific PCR primers were established and relative gene expression of human AKR1C family members was determined in paired samples of cancerous and surrounding unaffected prostate tissue. AKR1C2 preferentially reduces DHT to the weak metabolite 5 alpha-androstane-3 alpha,17 beta-diol (3 alpha-diol) without conversion of 3 alpha-diol to DHT in the PC-3 cell line, and its expression was increased by DHT treatment in LNCaP cells. Selectively reduced expression of AKR1C2 mRNA, but not AKR1C1 (97% sequence identity), was found in approximately half of the pairs whereas AKR1C3 relative expression was not significantly altered. No aberrant expression of AKR1C4 expression or significant differences in SRD5A2 gene expression were found. AKR1C2 functions as a DHT reductase in prostate-derived cells lines and is regulated by DHT. Additional studies are needed to further define the significance of reduced AKR1C2 expression in prostate cancer and its potential role in modulating local availability of DHT. Copyright 2003 Wiley-Liss, Inc.

  17. Synthesis of orthogonally protected bacterial, rare-sugar and D-glycosamine building blocks.

    Science.gov (United States)

    Emmadi, Madhu; Kulkarni, Suvarn S

    2013-10-01

    Bacterial glycoconjugates comprise atypical deoxy amino sugars that are not present on the human cell surface, making them good targets for drug discovery and carbohydrate-based vaccine development. Unfortunately, they cannot be isolated with sufficient purity in acceptable amounts, and therefore chemical synthesis is a crucial step toward the development of these products. Here we describe a detailed protocol for the synthesis of orthogonally protected bacterial deoxy amino hexopyranoside (2,4-diacetamido-2,4,6-trideoxyhexose (DATDH), D-bacillosamine, D-fucosamine, and 2-acetamido-4-amino-2,4,6-trideoxy-D-galactose (AAT)), D-glucosamine and D-galactosamine building blocks starting from β-D-thiophenylmannoside. Readily available β-D-thiophenylmannoside was first converted into the corresponding 2,4-diols via deoxygenation or silylation at C6, followed by O3 acylation. The 2,4-diols were converted into 2,4-bis-trifluoromethanesulfonates, which underwent highly regioselective, one-pot, double-serial and double-parallel displacements by azide, phthalimide, acetate and nitrite ions as nucleophiles. Thus, D-rhamnosyl- and D-mannosyl 2,4-diols can be efficiently transformed into various rare sugars and D-galactosamine, respectively, as orthogonally protected thioglycoside building blocks on a gram scale in 1-2 d, in 54-85% overall yields, after a single chromatographic purification. This would otherwise take 1-2 weeks. D-Glucosamine building blocks can be prepared from β-D-thiophenylmannoside in four steps via C2 displacement of triflates by azide in 2 d and in 66-70% overall yields. These procedures have been applied to the synthesis of L-serine-linked trisaccharide of Neisseria meningitidis and a rare disaccharide fragment of the zwitterionic polysaccharide (ZPS) A1 (ZPS A1) of Bacteroides fragilis.

  18. Four new sesqui-lignans isolated from Acanthopanax senticosus and their diacylglycerol acyltransferase (DGAT) inhibitory activity.

    Science.gov (United States)

    Li, Jia-Lin; Li, Na; Lee, Hyun-Sun; Xing, Shan-Shan; Qi, Shi-Zhou; Tuo, Zhen-Dong; Zhang, Le; Li, Ban-Ban; Chen, Jian-Guang; Cui, Long

    2016-03-01

    Four new sesqui-lignans, (7R, 7'R, 7″S, 8S, 8'S, 8″S)-4',5″-dihydroxy-3,5,3',4″-tetramethoxy-7,9':7',9-diepoxy-4,8″-oxy-8,8'-sesquineo-lignan-7″,9″-diol (1), (7R, 7'R, 7″S, 8S, 8'S, 8″S)-4',3″-dihydroxy-3,5,3',5',4″-pentamethoxy-7,9':7',9-diepoxy-4,8″-oxy-8,8'-sesquineo-lignan-7″,9″-diol (2), (7R, 7'R, 7″S, 8S, 8'S, 8″S)-3',4″-dihydroxy-3,5,4',5″-tetramethoxy-7,9':7',9-diepoxy-4,8″-oxy-8,8'-sesquineo-lignan-7″,9″-diol (3) and acanthopanax A (7) together with three known compounds (4-6) were isolated from the EtOAc-soluble extract of Acanthopanax senticosus. Their structures were elucidated on the basis of spectroscopic and physicochemical analyses. All the isolates were evaluated for in vitro inhibitory activity against DGAT1 and DGAT2. Among them, compounds 1-6 were found to exhibit selective inhibitory activity on DGAT1 with IC50 values ranging from 61.1 ± 1.3 to 97.7 ± 1.1 μM and compound 7 showed selective inhibition of DGAT2 with IC50 value 93.2 ± 1.2. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Influence of the molecular structure on hydrolysability of unsaturated polyesters

    International Nuclear Information System (INIS)

    Pays, M.F.; Denis, V.

    1993-09-01

    EDF has decided to replace conventional materials by glass reinforced plastics for certain PWR water distribution systems (raw water system, essential service water system, firefighting water distribution system, etc...). Since steel corrodes rapidly in these pipings, introducing composite materials will be economically beneficial if the long-term resistance of these materials can be guaranteed. However, due to hydrolysis of the resin or of the fiber-matrix interface, composite materials deteriorations may occur during service life. This paper reports on the hydrolysis resistance of polyester and vinylester resins. - Model monomers were studied to relate the molecular structure to the hydrolysis resistance. Two ester categories were determined, the diacids and the diols. For the diacids, we obtained the following classification in increasing order of resistance: < maleates < ethoxysuccinates < succinates < fumerates < terephtalates < orthophtalates < isophtalates and for the diols: trioxyethylene glycol << butane diol ∼ ethylene glycol < neopentyl glycol < bisphenol A. The positions obtained for neopentyl glycol and isophtalic acid on this scale justify their inclusion in the formulation of hydrolysis-resistant resins. Since aliphatic unsaturated esters are highly sensitive to hydrolysis, the cross linking procedures for these materials, notably the post-cure stages, must be the subject of particular care. - The hydrolytic degradation of cross linked materials was studied. It was shown that hydrolysis could be monitored by a simple gravimetric method. Used in association with accelerated aging tests, it predicts the time lapse to initiation of the phenomenon. The better hydrolysis resistance of vinylester resins as compared with unsaturated polyesters has been demonstrated. However, forecasting over a 30-year life span is difficult to guarantee in that this involves indicating in the resin specifications the in-service stress which it will be required to

  20. Sexuality and fertility in women with Addison's disease.

    Science.gov (United States)

    Erichsen, Martina M; Husebye, Eystein S; Michelsen, Trond M; Dahl, Alv A; Løvås, Kristian

    2010-09-01

    Females with primary adrenal insufficiency (Addison's disease) have reduced levels of circulating androgens, which are allegedly important for sexual functioning. The aim was to determine peripheral androgen status, sexual functioning, and birth rates in Addison's disease females. In a postal survey, all 269 females in the Norwegian Addison's registry were invited to complete the Sexual Activity Questionnaire (SAQ) and registration of childbirths. Blood samples were analyzed for 5alpha-androstane-3alpha,17beta-diol-3-glucuronide (3alpha-Diol-G) and compared with blood donor levels. The SAQ scores were compared with 740 age-matched controls from the general population and 234 women subjected to risk-reducing salpingo-oophorectomy. Fertility was estimated as standardized incidence ratio for birth; the expected number of births was estimated from population statistics. The SAQ was completed by 174 (65%) of the Addison's patients. Those not taking DHEA had significantly lower 3alpha-Diol-G levels than blood donors (mean, 0.53 vs. 2.2 ng/ml; P Addison's disease females were equally sexually active as the controls, but they reported significantly higher pleasure and less discomfort. They reported lower pleasure but less discomfort than the risk-reducing salpingo-oophorectomy women. The fertility was significantly reduced in females with Addison's disease; 54 children were born to mothers with established diagnosis (87.5 expected), yielding a standardized incidence ratio for birth of 0.69 (confidence interval, 0.52-0.86). Despite androgen depletion, females with Addison's disease do not report impaired sexuality. The fertility is reduced after the diagnosis is made; the reasons for this remain unknown.

  1. Mechanisms of interaction of radiation with matter

    International Nuclear Information System (INIS)

    Geacintov, N.E.; Pope, M.

    1993-01-01

    This project is concerned with the mechanisms by which polynuclear aromatic (PNA) compounds on the one hand, and ionizing radiation on the other, cause damage to DNA. PNA compounds constitute an important class of environmental pollutants derived from energy-related sources which, upon metabolic activation to diolepoxide derivatives, produce bulky PNA-DNA lesions interfere with the normal DNA replication and transcription processes, and give rise to mutations and the initiation of tumors. Chiral and other stereochemical effects play a key role in determining the biological effects of a given PNA diol epoxide and the potentially mutagenic lesions which are formed. New and efficient methods for synthesizing stereochemically pure and precisely positioned PNA diol epoxide-DNA lesions in small DNA fragments are reported here. We have elucidated the structures of three stereoisomeric benzo[a]pyrene diol epoxide-DNA adducts. How these adducts affect on DNA polymerase fidelity, transcription, and DNA repair are currently being investigated with respect to detailed structure-biological activity correlations. Spectroscopic techniques such as circular dichroism, fluorescence, and photoionization play an important role in the characterizations of the PNA adducts. A new method was developed for measuring the lifetimes as well as the energies of picosecond duration electronically excited states. Using this technique, it is proposed that short-lived (15 ps) charge-transfer (CT) states in the PNA compound tetracene are activated by a 20 ps laser pulse; an unusual external photoemission echo do to the recombination of CT states is observed 85 ps after the pulse

  2. Effect of Prenatal Polycyclic Aromatic Hydrocarbons Exposure on Birth Outcomes: The Polish Mother and Child Cohort Study

    Directory of Open Access Journals (Sweden)

    Kinga Polanska

    2014-01-01

    Full Text Available The aim of this study was to assess the impact of PAH exposure on various anthropometric measures of birth outcomes. The study population consisted of 210 nonsmoking pregnant women. Urine samples collected between 20th and 24th week of pregnancy were used for analysis of the following PAH metabolites: 1-, 2-, 3-, 4-, and 9-hydroxyphenanthrene (1-, 2-, 3-, 4-, and 9-OH-PHE, 1-hydroxypyrene (1-OH-PYR, 1,6 + 1,8-dihydroxypyrene (DI-OH-PYR, phenanthrene trans-1,2-dihydrodiol (PHE-1,2-diol, and phenanthrene trans-9,10-dihydrodiol (PHE-9,10-diol by gas chromatography-mass spectrometry. Environmental tobacco smoke exposure (ETS was assessed by cotinine level in saliva using a stable isotope dilution LC-ESI-MS/MS method. The mean PAH metabolite concentrations were in the range of 0.15 µg/g creatinine for 9-OH-PHE to 5.9 µg/g creatinine for PHE-9,10-diol. It was shown that none of the individual PAH exposure markers demonstrate a statistically significant influence on birth outcomes. Interestingly a statistically significant association was found between the sum of OH-PHE along with cotinine level and the cephalization index after adjusting for potential confounders (P=0.04. This study provides evidence that combined exposure of pregnant women to common environmental pollutants such as PAH and ETS might adversely affect fetal development. Thus, reduction of human exposure to these mixtures of hazardous compounds would in particular result in substantial health benefits for newborns.

  3. Stereodivergent Synthesis of 1,3-Syn-Polyol Natural Product for Stereochemical-Based Structure Activity Relationship Studies

    Science.gov (United States)

    Zheng, Jiamin

    The 1,3-syn-diol functionality is very common in many natural products. An important class containing this moiety are the 1,3-syn-polyol/pyranone natural products, which have been isolated from a variety of plant sources, and possess biological activities like plant growth inhibition as well as antifeedant, antifungal, antibacterial, and antitumor properties. The feature of this class is a 6-membered lactone where the lactoe oxygen is part of a 1,3-syn-diol motif. To pursue the 1,3-syn-polyol/pyranone natural products, an iterative hydration of polyene strategy was utilized to provide the 1,3- syn-diol functionality, and asymmetric synthetic strategies were explored to form the requisite stereochemistry. The versatility of the asymmetric approach was demonstrated in the synthesis of eupatorium pyranone and also in an ongoing project aimed at the synthesis of SIA7248. As an outgrowth of our work on the total syntheses of 1,3-syn -polyol natural products inspired a stereo-divergent synthesis of 1,3-syn-polyol natural products and their analogs for stereochemical-based structure-activity relationship (SSAR) studies. To identify the key structural factors important for the anticancer activity of the 1,3-syn-polyol/pyranones, a stereo-divergent 16-member library of pyranone/polyol congeners was designed, synthesized and tested with variations in both stereochemistry and numbers of polyol repeat units. Having access to stereochemical isomers of the biologically active natural products allowed us to design experiments that help illustrate their mechanisms of action.

  4. The catalytic mechanism of mouse renin studied with QM/MM calculations.

    Science.gov (United States)

    Brás, Natércia F; Ramos, Maria J; Fernandes, Pedro A

    2012-09-28

    Hypertension is a chronic condition that affects nearly 25% of adults worldwide. As the Renin-Angiotensin-Aldosterone System is implicated in the control of blood pressure and body fluid homeostasis, its combined blockage is an attractive therapeutic strategy currently in use for the treatment of several cardiovascular conditions. We have performed QM/MM calculations to study the mouse renin catalytic mechanism in atomistic detail, using the N-terminal His6-Asn14 segment of angiotensinogen as substrate. The enzymatic reaction (hydrolysis of the peptidic bond between residues in the 10th and 11th positions) occurs through a general acid/base mechanism and, surprisingly, it is characterized by three mechanistic steps: it begins with the creation of a first very stable tetrahedral gem-diol intermediate, followed by protonation of the peptidic bond nitrogen, giving rise to a second intermediate. In a final step the peptidic bond is completely cleaved and both gem-diol hydroxyl protons are transferred to the catalytic dyad (Asp32 and Asp215). The final reaction products are two separate peptides with carboxylic acid and amine extremities. The activation energy for the formation of the gem-diol intermediate was calculated as 23.68 kcal mol(-1), whereas for the other steps the values were 15.51 kcal mol(-1) and 14.40 kcal mol(-1), respectively. The rate limiting states were the reactants and the first transition state. The associated barrier (23.68 kcal mol(-1)) is close to the experimental values for the angiotensinogen substrate (19.6 kcal mol(-1)). We have also tested the influence of the density functional on the activation and reaction energies. All eight density functionals tested (B3LYP, B3LYP-D3, X3LYP, M06, B1B95, BMK, mPWB1K and B2PLYP) gave very similar results.

  5. Increased 5. cap alpha. -reductase activity in idiopathic hirsutism

    Energy Technology Data Exchange (ETDEWEB)

    Serafini, P.; Lobo, R.A.

    1985-01-01

    In vitro, genital skin 5..cap alpha..-reductase activity (5..cap alpha..-RA) was measured in ten hirsute women with normal androgen levels (idiopathic hirsutism (IH)) and in ten hirsute women with elevated androgen levels (polycystic ovary syndrome (PCO)) in order to determine the influence of secreted androgens on 5..cap alpha..-RA. In vitro 5..cap alpha..-RA was assessed by incubations of skin with /sup 14/C-testosterone (T) for 2 hours, after which steroids were separated and the radioactivity of dihydrotestosterone (DHT) and 5..cap alpha..-androstane 3..cap alpha..-17..beta..-estradiol (3..cap alpha..-diol) in specific eluates were determined. All androgens were normal in IH with the exception of higher levels of 3..cap alpha..-diol glucuronide which were similar to the levels of PCO. The conversion ratio (CR) of T to DHT in IH and PCO were similar, yet significantly greater than the CR of control subjects. The CR of T to 3..cap alpha..-diol in IH and PCO were similar, yet higher than in control subjects. Serum androgens showed no correlation with 5..cap alpha..-RA, while the CR of T to DHT showed a significant positive correlation with the Ferriman and Gallwey score. The increased 5..cap alpha..-RA in IH appears to be independent of serum androgen levels and is, therefore, an inherent abnormality. The term idiopathic is a misnomer, because hirsutism in these patients may be explained on the basis of increased skin 5..cap alpha..-RA.

  6. Effect of prenatal polycyclic aromatic hydrocarbons exposure on birth outcomes: the Polish mother and child cohort study.

    Science.gov (United States)

    Polanska, Kinga; Dettbarn, Gerhard; Jurewicz, Joanna; Sobala, Wojciech; Magnus, Per; Seidel, Albrecht; Hanke, Wojciech

    2014-01-01

    The aim of this study was to assess the impact of PAH exposure on various anthropometric measures of birth outcomes. The study population consisted of 210 nonsmoking pregnant women. Urine samples collected between 20th and 24th week of pregnancy were used for analysis of the following PAH metabolites: 1-, 2-, 3-, 4-, and 9-hydroxyphenanthrene (1-, 2-, 3-, 4-, and 9-OH-PHE), 1-hydroxypyrene (1-OH-PYR), 1,6 + 1,8-dihydroxypyrene (DI-OH-PYR), phenanthrene trans-1,2-dihydrodiol (PHE-1,2-diol), and phenanthrene trans-9,10-dihydrodiol (PHE-9,10-diol) by gas chromatography-mass spectrometry. Environmental tobacco smoke exposure (ETS) was assessed by cotinine level in saliva using a stable isotope dilution LC-ESI-MS/MS method. The mean PAH metabolite concentrations were in the range of 0.15 µg/g creatinine for 9-OH-PHE to 5.9 µg/g creatinine for PHE-9,10-diol. It was shown that none of the individual PAH exposure markers demonstrate a statistically significant influence on birth outcomes. Interestingly a statistically significant association was found between the sum of OH-PHE along with cotinine level and the cephalization index after adjusting for potential confounders (P = 0.04). This study provides evidence that combined exposure of pregnant women to common environmental pollutants such as PAH and ETS might adversely affect fetal development. Thus, reduction of human exposure to these mixtures of hazardous compounds would in particular result in substantial health benefits for newborns.

  7. Base sequence effects on DNA replication influenced by bulky adducts. Final report, March 1, 1995--February 28, 1997

    Energy Technology Data Exchange (ETDEWEB)

    Geacintov, N.E.

    1997-05-31

    Polycyclic aromatic hydrocarbons (PAH) are environmental pollutants that are present in air, food, and water. While PAH compounds are chemically inert and are sparingly soluble in aqueous solutions, in living cells they are metabolized to a variety of oxygenated derivatives, including the high mutagenic and tumorigenic diol epoxide derivatives. The diol epoxides of the sterically hindered fjord region compound benzo[c]phenanthrene (B[c]PhDE) are among the most powerful tumorigenic compounds in animal model test systems. In this project, site-specifically modified oligonucleotides containing single B[c]PhDE-N{sup 6}-dA lesions derived from the reactions of the 1S,2R,3R,4S and 1R,2S,3S,4R diol epoxides of B[c]PhDE with dA residues were synthesized. The replication of DNA catalyzed by a prokaryotic DNA polymerase (the exonuclease-free Klenow fragment E. Coli Po1 I) in the vicinity of the lesion at base-specific sites on B[c]PhDE-modified template strands was investigated in detail. The Michaelis-Menten parameters for the insertion of single deoxynucleotide triphosphates into growing DNA (primer) strands using the modified dA* and the bases just before and after the dA* residue as templates, depend markedly on the stereochemistry of the B[c]PhDE-modified dA residues. These observations provide novel insights into the mechanisms by which bulky PAH-DNA adducts affect normal DNA replication.

  8. Enantioselective Copper-Catalyzed Oxy-Alkynylation of Diazo Compounds.

    Science.gov (United States)

    Hari, Durga Prasad; Waser, Jerome

    2017-06-28

    Enantioselective catalytic methods allowing the addition of both a nucleophile and an electrophile onto diazo compounds give a fast access into important building blocks. Herein, we report the highly enantioselective oxyalkynylation of diazo compounds using ethynylbenziodoxol-(on)e reagents and a simple copper bisoxazoline catalyst. The obtained α-benzoyloxy propargylic esters are useful building blocks, which are difficult to synthesize in enantiopure form using other methods. The obtained products could be efficiently transformed into vicinal diols and α-hydroxy propargylic esters without loss in enantiopurity.

  9. Preparation of Mesoporous SBA-16 Silica-Supported Biscinchona Alkaloid Ligand for the Asymmetric Dihydroxylation of Olefins

    Directory of Open Access Journals (Sweden)

    Shaheen M. Sarkar

    2014-01-01

    Full Text Available Optically active cinchona alkaloid was anchored onto mesoporous SBA-16 silica and the as-prepared complex was used as a heterogeneous chiral ligand of osmium tetraoxide for the asymmetric dihydroxylation of olefins. The prepared catalytic system provided 90–93% yield of vicinal diol with 92–99% enantioselectivity. The ordered mesoporous SBA-16 silica was found to be a valuable support for the cinchona alkaloid liganded osmium catalyst system which is frequently used in chemical industries and research laboratories for olefin functionalization.

  10. Synthesis, crystal structure and biological activity of novel diester cyclophanes

    International Nuclear Information System (INIS)

    Zhang, Pengfei; Yang, Bingqin; Fang, Xianwen; Cheng, Zhao; Yang, Meipan

    2012-01-01

    A series of novel diester cyclophanes was synthesized by esterification of 1,2-benzenedicarbonyl chloride with eight different diols under high dilution conditions. The structures of the compounds were verified by elemental analysis, 1 H nuclear magnetic resonance (NMR), IR spectroscopy and high resolution mass spectrometry (HRMS). The crystal structures of two compounds were characterized by single crystal X-ray diffractometry (XRD). All the new cyclophanes were evaluated for biological activities and the results showed that some of these compounds have low antibacterial or antifungal activities (author)

  11. Combustion and Heat Transfer Studies Utilizing Advanced Diagnostics: Fuels Research

    Science.gov (United States)

    1992-11-01

    competing reactions (Reactions (6) and (7)) and their respective rate equations (Eqs. 8 and 9). Reaction (6) has the advantage of no activation energy and...cartridges were J&W (diol, cyano and C-18) J.T. Baker (silica gel) and Alltech (IC/Ag). All were conditioned and used according to the vendors...hot fuel through the test section. At the same time the water supply to the fuel cooler is turned on. The main advantage of this procedure is that it

  12. Determination of boron in uranium and aluminium by high pressure liquid chromatography (HPLC)

    International Nuclear Information System (INIS)

    Rao, Radhika M.; Aggarwal, S.K.

    2003-01-01

    Experiments were conducted for the determination of boron in U 3 O 8 powder and aluminium metal using dynamically modified reversed phase high pressure liquid chromatography (RP-HPLC) and using precolumn chromogenic agent viz. curcumin for complexing boron. The complex was separated from the excess of reagent and determined by HPLC. The boron curcumin complex (rosocyanin) was formed after extraction of boron with 2-ethyl-1,3-hexane diol (EHD). Linear calibration curves for boron amounts in the range of 0.02 μg to 0.5 μg were developed and used for the determination of boron in aluminium and uranium samples. (author)

  13. Progress in the chemistry of chromium(V) doping agents used in polarized target materials

    International Nuclear Information System (INIS)

    Krumpolc, M.; Hill, D.; Struhrmann, H.B.

    1990-01-01

    We wish to report progress in two areas of the chromium (V)-based doping agents: Two commonly used chromium (V) complexes, I and II, have been synthesized in perdeuterated form (i.e., all hydrogens replaced by deuterium). They are sodium bis(2-ethyl-2-deuteroxy-butyrato)oxochromate(V)monodeuterate, IV, (acronym EDBA-Cr(V)), and sodium bis(2-deuteroxy-2-methylpropionato)oxochromate(V), III, (acronym DMPA-Cr(V)). A synthetic route leading to the preparation of stable, chromium(III)-free solutions of chromium(V) in diols (1,2-ethanediol/ethylene glycol/and 1,2-propanediol/propylene glycol/) has been outlined

  14. Functionalization of epoxy esters with alcohols as stoichiometric reagents.

    Science.gov (United States)

    Pavlović, Dona; Modec, Barbara; Dolenc, Darko

    2015-01-01

    Glycidyl esters, frequently employed as reactive groups on polymeric supports, were functionalized with alcohols as stoichiometric reagents, yielding β-alkoxyalcohols. Among the solvents studied, best results were obtained in ethers in the presence of a strong proton acid as a catalyst. Alcohols include simple alkanols, diols, protected polyols, 3-butyn-1-ol 3-hydroxypropanenitrile and cholesterol. This protocol represents a convenient way for introduction of various functionalities onto epoxy-functionalized polymers. Under the reaction conditions, some side reactions take place, mostly due to the reactive ester group and water present in the reaction mixture.

  15. Quinine-Promoted, Enantioselective Boron-Tethered Diels-Alder Reaction by Anomeric Control of Transition State Conformation.

    Science.gov (United States)

    Scholl, Katie; Dillashaw, John; Timpy, Evan; Lam, Yu-Hong; DeRatt, Lindsey; Benton, Tyler R; Powell, Jacqueline P; Houk, Kendall N; Morgan, Jeremy B

    2018-05-01

    Diels-Alder reactions of tethered vinyl-metal species offer the opportunity to fashion highly functionalized diol intermediates for synthesis. We have developed the first enantioselective boron-tethered Diels-Alder reaction using quinine as a chiral promoter. Quinine recovery, enantioselectivity enhancement, and manipulation of the cyclohexene core are also investigated. DFT modeling calculations confirm the role of quinine as a bidentate ligand enhancing reaction rates. The enantioselectivity of the cycloaddition is proposed to originate from a boron-centered anomeric effect.

  16. Identification of chemical compounds present in different fractions of Annona reticulata L. leaf by using GC-MS.

    Science.gov (United States)

    Rout, Soumya P; Kar, Durga M

    2014-01-01

    GC-MS analysis of fractions prepared from hydro-alcoholic extract of Annona reticulata Linn (Family Annonaceae) leaf revealed the presence of 9,10-dimethyltricyclo[4.2.1.1(2,5)]decane-9,10-diol; 4-(1,5-dihydroxy-2,6,6-trimethylcyclohex-2-enyl)but-3-en-2-one; 3,7-dimethyl-6-nonen-1-ol acetate; 9-octadecenamide,(Z)-; glycerine; D-glucose,6-O-α-D-galactopyranosyl-; desulphosinigrin and α-methyl-D-mannopyranoside as few of the major compounds in different fractions. The presence of these compounds in the plant has been identified for the first time.

  17. Exploring Cooperative Effects in Oxidative NHC Catalysis: Regioselective Acylation of Carbohydrates.

    Science.gov (United States)

    Cramer, David L; Bera, Srikrishna; Studer, Armido

    2016-05-23

    The utility of oxidative NHC catalysis for both the regioselective and chemoselective functionalization of carbohydrates is explored. Chiral NHCs allow for the highly regioselective oxidative esterification of various carbohydrates using aldehydes as acylation precursors. The transformation was also shown to be amenable to both cis/trans diol isomers, free amino groups, and selective for specific sugar epimers in competition experiments. Efficiency and regioselectivity of the acylation can be improved upon using two different NHC catalysts that act cooperatively. The potential of the method is documented by the regioselective acylation of an amino-linked neodisaccharide. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Sugar-Responsive Pseudopolyrotaxane Composed of Phenylboronic Acid-Modified Polyethylene Glycol and γ-Cyclodextrin

    Directory of Open Access Journals (Sweden)

    Tomohiro Seki

    2015-03-01

    Full Text Available We have designed a sugar-responsive pseudopolyrotaxane (PPRX by combining phenylboronic acid-modified polyethylene glycol (PBA–PEG and γ-cyclodextrin. Phenylboronic acid (PBA was used as a sugar-recognition motif in the PPRX because PBA reacts with a diol portion of the sugar molecule and forms a cyclic ester. When D-fructose or D-glucose was added to a suspension of PPRX, PPRX disintegrated, depending on the concentration of the sugars. Interestingly, catechol does not show a response although catechol has a high affinity for PBA. We analyzed the response mechanism of PPRX by considering equilibria.

  19. Radiation resistance and molecular structure of poly(arylene ether sulphone)s

    International Nuclear Information System (INIS)

    Hill, D.J.T.; Lewis, D.A.; O'Donnell, J.H.; Pomery, P.J.; Hedrick, J.L.; McGrath, J.E.

    1991-01-01

    The radiation resistance of a series of aromatic polysulfones comprising alternating units of diphenyl sulfone and various aromatic diols has been investigated by measuring volatile products, soluble fractions and electron spin resonance (ESR) spectra. The yields of radicals at 77 K observed by ESR and of SO 2 at 423 K have indicated that biphenol gives enhanced resistance to γ radiation, and tetramethyl bisphenol-A decreased resistance, relative to bisphenol-A, bisphenol-S and hydroquinone. The protective effect of biphenol was confirmed by lower scission and crosslinking yields determined from the soluble fractions after high doses. (author)

  20. Cannabinoid Type 1 Receptor (CB1) Ligands with Therapeutic Potential for Withdrawal Syndrome in Chemical Dependents of Cannabis sativa.

    Science.gov (United States)

    Ferreira, Jaderson V; Chaves, Gisele A; Marino, Bianca L B; Sousa, Kessia P A; Souza, Lucilene R; Brito, Maiara F B; Teixeira, Hueldem R C; da Silva, Carlos H T P; Santos, Cleydson B R; Hage-Melim, Lorane I S

    2017-08-22

    Cannabis sativa withdrawal syndrome is characterized mainly by psychological symptoms. By using computational tools, the aim of this study was to propose drug candidates for treating withdrawal syndrome based on the natural ligands of the cannabinoid type 1 receptor (CB1). One compound in particular, 2-n-butyl-5-n-pentylbenzene-1,3-diol (ZINC1730183, also known as stemphol), showed positive predictions as a human CB1 ligand and for facile synthetic accessibility. Therefore, ZINC1730183 is a favorable candidate scaffold for further research into pharmacotherapeutic alternatives to treat C. sativa withdrawal syndrome. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Lanthanide tris(β-diketonates) as useful probes for chirality determination of biological amino alcohols in vibrational circular dichroism: ligand to ligand chirality transfer in lanthanide coordination sphere.

    Science.gov (United States)

    Miyake, Hiroyuki; Terada, Keiko; Tsukube, Hiroshi

    2014-06-01

    A series of lanthanide tris(β-diketonates) functioned as useful chirality probes in the vibrational circular dichroism (VCD) characterization of biological amino alcohols. Various chiral amino alcohols induced intense VCD signals upon ternary complexation with racemic lanthanide tris(β-diketonates). The VCD signals observed around 1500 cm(-1) (β-diketonate IR absorption region) correlated well with the stereochemistry and enantiomeric purity of the targeted amino alcohol, while the corresponding monoalcohol, monoamine, and diol substrates induced very weak VCD signals. The high-coordination number and dynamic property of the lanthanide complex offer an effective chirality VCD probing of biological substrates. © 2014 Wiley Periodicals, Inc.

  2. Local Fatigue Evaluation in PZT Thin Films with Nanoparticles by Piezoresponse Force Microscopy

    OpenAIRE

    B. S. Li

    2012-01-01

    Lead zirconate titanate (PZT) thin films with the morphotropic phase boundary composition (Zr/Ti = 52/48) have been prepared using a modified diol-based sol-gel route by introducing 1–5 mol% barium titanate (BT) nanoseeds into the precursor solution on platinized silicon substrates (Pt/Ti/SiO2/Si). Macroscopic electric properties of PZT film with nanoparticle showed a significant improvement of ferroelectric properties. This work aims at the systematic study of the local switching polarizatio...

  3. Asymmetric Meerwein–Ponndorf–Verley reduction of long chain keto alkanoic acid methyl esters

    Directory of Open Access Journals (Sweden)

    AYE YUSUFOGLU

    2007-05-01

    Full Text Available 3-, 7- and 13-Monoketo tetradecanoic acid methyl esters carrying a ketogroup at the ends and at the middle of the chain with 14 carbon atoms were reduced by a Meerwein–Ponndorf–Verley reaction in the presence of R-(+-1,1'-binaphthalene-2,2'-diol, 1,2:5,6-D-di-O-isopropylidene-D-mannitol and L-(–-menthol. The highest enantiomeric purity of 65% ee was found for 13-hydroxy ester isomer. The enantiomeric excess was determined by 1H-NMR shift with Eu(tfc3 and by optical rotation.

  4. Synthesis, crystal structure and biological activity of novel diester cyclophanes

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Pengfei; Yang, Bingqin; Fang, Xianwen; Cheng, Zhao; Yang, Meipan, E-mail: yangbq@nwu.edu.cn [Department of Chemistry, Key Laboratory of Synthetic and Natural Functional Molecule Chemistry, Northwest University, Shaanxi (China)

    2012-10-15

    A series of novel diester cyclophanes was synthesized by esterification of 1,2-benzenedicarbonyl chloride with eight different diols under high dilution conditions. The structures of the compounds were verified by elemental analysis, {sup 1}H nuclear magnetic resonance (NMR), IR spectroscopy and high resolution mass spectrometry (HRMS). The crystal structures of two compounds were characterized by single crystal X-ray diffractometry (XRD). All the new cyclophanes were evaluated for biological activities and the results showed that some of these compounds have low antibacterial or antifungal activities (author)

  5. trans-2-Tritylcyclohexanol as a chiral auxiliary in permanganate-mediated oxidative cyclization of 2-methylenehept-5-enoates: application to the synthesis of trans-(+)-linalool oxide.

    Science.gov (United States)

    Al Hazmi, Ali M; Sheikh, Nadeem S; Bataille, Carole J R; Al-Hadedi, Azzam A M; Watkin, Sam V; Luker, Tim J; Camp, Nicholas P; Brown, Richard C D

    2014-10-03

    The permanganate-mediated oxidative cyclization of a series of 2-methylenehept-5-eneoates bearing different chiral auxiliaries was investigated, leading to the discovery of trans-2-tritylcyclohexanol (TTC) as a highly effective chiral controller for the formation of the 2,5-substituted THF diol product with high diastereoselectivity (dr ∼97:3). Chiral resolution of (±)-TTC, prepared in one step from cyclohexene oxide, afforded (-)-(1S,2R)-TTC (er >99:1), which was applied to the synthesis of (+)-trans-(2S,5S)-linalool oxide.

  6. Síntese da Epoxone a partir de D-frutose: um experimento didático em laboratório de Química Orgânica com foco nos princípios da Química Verde

    Directory of Open Access Journals (Sweden)

    Tula Beck Bisol

    2012-01-01

    Full Text Available In recent years, the introduction of the Green Chemistry concepts in undergraduate chemistry classes has been intensively pursued. In this regard, the two-step preparation of Epoxone (an organocatalyst developed by Shi & col. from commercial D-fructose, through ketalization of vicinal diols followed by oxidation of a sterically congested secondary alcohol, involves important topics in Organic Chemistry and employs inexpensive and nontoxic reagents. The reactions are easy to perform and the products from both steps are readily obtained as crystalline solids after simple procedures, thus facilitating their chemical characterization.

  7. Bidirectional cross metathesis and ring-closing metathesis/ring opening of a C2-symmetric building block: a strategy for the synthesis of decanolide natural products

    Directory of Open Access Journals (Sweden)

    Bernd Schmidt

    2013-11-01

    Full Text Available Starting from the conveniently available ex-chiral pool building block (R,R-hexa-1,5-diene-3,4-diol, the ten-membered ring lactones stagonolide E and curvulide A were synthesized using a bidirectional olefin-metathesis functionalization of the terminal double bonds. Key steps are (i a site-selective cross metathesis, (ii a highly diastereoselective extended tethered RCM to furnish a (Z,E-configured dienyl carboxylic acid and (iii a Ru–lipase-catalyzed dynamic kinetic resolution to establish the desired configuration at C9. Ring closure was accomplished by macrolactonization. Curvulide A was synthesized from stagonolide E through Sharpless epoxidation.

  8. Stereospecific oxidation of (R)- and (S)-1-indanol by naphthalene dioxygenase from Pseudomonas sp. strain NCIB 9816-4.

    OpenAIRE

    Lee, K; Resnick, S M; Gibson, D T

    1997-01-01

    A recombinant Escherichia coli strain which expresses naphthalene dioxygenase (NDO) from Pseudomonas sp. strain NCIB 9816-4 oxidized (S)-1-indanol to trans-(1S,3S)-indan-1,3-diol (95.5%) and (R)-3-hydroxy-1-indanone (4.5%). The same cells oxidized (R)-1-indanol to cis-1,3-indandiol (71%), (R)-3-hydroxy-1-indanone (18.2%), and cis-1,2,3-indantriol (10.8%). Purified NDO oxidized (S)-1-indenol to both syn- and anti-2,3-dihydroxy-1-indanol.

  9. Stereospecific oxidation of (R)- and (S)-1-indanol by naphthalene dioxygenase from Pseudomonas sp. strain NCIB 9816-4.

    Science.gov (United States)

    Lee, K; Resnick, S M; Gibson, D T

    1997-05-01

    A recombinant Escherichia coli strain which expresses naphthalene dioxygenase (NDO) from Pseudomonas sp. strain NCIB 9816-4 oxidized (S)-1-indanol to trans-(1S,3S)-indan-1,3-diol (95.5%) and (R)-3-hydroxy-1-indanone (4.5%). The same cells oxidized (R)-1-indanol to cis-1,3-indandiol (71%), (R)-3-hydroxy-1-indanone (18.2%), and cis-1,2,3-indantriol (10.8%). Purified NDO oxidized (S)-1-indenol to both syn- and anti-2,3-dihydroxy-1-indanol.

  10. Phosphate Tether-Mediated Ring-Closing Metathesis for the Generation of P-Stereogenic, Z-Configured Bicyclo[7.3.1]- and Bicyclo[8.3.1]phosphates.

    Science.gov (United States)

    Markley, Jana L; Maitra, Soma; Hanson, Paul R

    2016-02-05

    A phosphate tether-mediated ring-closing metathesis (RCM) study to the synthesis of Z-configured, P-stereogenic bicyclo[7.3.1]- and bicyclo[8.3.1]phosphates is reported. Investigations suggest that C3-substitution, olefin substitution, and proximity of the forming olefin to the bridgehead carbon of the bicyclic affect the efficiency and stereochemical outcome of the RCM event. This study demonstrates the utility of phosphate tether-mediated desymmetrization of C2-symmetric, 1,3-anti-diol-containing dienes in the generation of macrocyclic phosphates with potential synthetic and biological utility.

  11. Synthesis of dithiotherdithiols, potential technetium complexing agents

    International Nuclear Information System (INIS)

    Alagui, A.; Apparu, M.; Vidal, M.; Pasqualini, R.

    1991-01-01

    The following dithioetherdithiols: 2.10-dimethyl-4.8-dithiaundecane-2.10-dithiol (1), 5-butyl-3.7-dithianonane-1.9-dithiol (2) and 4.4,6.6-tetramethyl-3.7-dithianonane-1.9-dithiol (3) have been synthesized. These compounds are very attractive as potential precursors of technetiated radiopharmaceuticals. While the syntheses of compounds (1) and (2) have been achieved satisfactorily, that of (3) unfortunately could not be effected: the reaction of ethanedithiol (or of its monobenzylated or monobenzoylated derivatives) with 2.4-dimethylpentane-2.4-diol leads mostly to cyclization or fragmentation products [fr

  12. Studies on the constituents of Gentiana species. II. A new triterpenoid, and (S)-(+)- and (R)-(-)-gentiolactones from Gentiana lutea.

    Science.gov (United States)

    Kakuda, Rie; Machida, Koichi; Yaoita, Yasunori; Kikuchi, Masafumi; Kikuchi, Masao

    2003-07-01

    A new triterpenoid, 12-ursene-3beta, 11alpha-diol 3-O-palmitate (1), has been isolated from the rhizomes and roots of Gentiana lutea, together with the artificial diene derivative, 9 (11), 12-ursadien-3beta-ol 3-O-palmitate (1a) and five known compounds (3-7). Their structures were established on the basis of spectral analysis. In addition, (+/-)-gentiolactone [(+/-)-2], isolated from this plant, was successfully separated into its enantiomers [(+)-2, (-)-2] for the first time, and the absolute configurations at C-9 of (+)-2, (-)-2 were assigned as S and R, respectively, from the optical rotations and the circular dichroism (CD) spectral data.

  13. Novel cross-linkers for PDMS networks for controlled and well distributed grafting of functionalities by click chemistry

    DEFF Research Database (Denmark)

    Bahrt, Frederikke; Dimitrov, Ivaylo; Daugaard, Anders Egede

    2013-01-01

    by 35%. The contact angle of PDMS films was increased from 108° to 116° by the introduction of a small poly(pentafluorostyrene) chain. Finally, 17α-ethynyl-1,3,5(10)-estratriene-3,17β-diol and 1-ethynyl-3,5- bis(trifluoromethyl)benzene were incorporated as examples of other functional groups. © 2013......-linkers have been utilized to prepare novel polydimethylsiloxane (PDMS) networks. All functional cross-linkers were successfully incorporated into the networks and were demonstrated to be well distributed within the PDMS films. This was substantiated by fluorescence microscopy of a film prepared with the 4...

  14. Application of combinatorial biocatalysis for a unique ring expansion of dihydroxymethylzearalenone.

    Science.gov (United States)

    Rich, Joseph O; Budde, Cheryl L; McConeghey, Luke D; Cotterill, Ian C; Mozhaev, Vadim V; Singh, Sheo B; Goetz, Michael A; Zhao, Annie; Michels, Peter C; Khmelnitsky, Yuri L

    2009-06-01

    Combinatorial biocatalysis was applied to generate a diverse set of dihydroxymethylzearalenone analogs with modified ring structure. In one representative chemoenzymatic reaction sequence, dihydroxymethylzearalenone was first subjected to a unique enzyme-catalyzed oxidative ring opening reaction that creates two new carboxylic groups on the molecule. These groups served as reaction sites for further derivatization involving biocatalytic ring closure reactions with structurally diverse bifunctional reagents, including different diols and diamines. As a result, a library of cyclic bislactones and bislactams was created, with modified ring structures covering chemical space and structure activity relationships unattainable by conventional synthetic means.

  15. Chemical constituents of Aristolochia giberti

    International Nuclear Information System (INIS)

    Marchesini, Alessandra M.; Prado, Giovana G.; Messiano, Gisele B.; Machado, Marcos B.; Lopes, Lucia M.X.

    2009-01-01

    Fourteen compounds were isolated from Aristolochia giberti. These included a new triterpene, (-)-onocera-8,8'-diol. In addition, 3-hydroxypropanoate, acetate, and formate were detected by NMR techniques, which suggests that they are derivatives from 2-butynedioate, which is not detected by 1 H NMR. GC-MS and chemometric analyses of essential oils from stems and leaves showed great similarity between this cultivated species in Brazil and that in Argentina, which allowed to confirm the species identity and to differentiate the oils according to the plant parts. (author)

  16. The Determination of Sugars by Chromatographic Method

    OpenAIRE

    Sumartini, Sri; Kantasubrata, Julia

    1992-01-01

    Experiments have been carried out to analyse sugars using TLC and HPLC methods, In the TLC method, separation of sugars was performed on silica plates impregnated with monosodium phosphate and using mixture of ethylacettuel pyridinde/water as an eluent. Whilst in the HPLC method, the use of three column types i.e. diol, RP-18 and modified silica column were tested. The results showed that TLC method was able to measure three sugars i:e. sucrose, glucose and fructose with standard deviations o...

  17. Determination of octanol-water partition coefficients of polar polycyclic aromatic compounds (N-PAC) by high performance liquid chromatography

    DEFF Research Database (Denmark)

    Helweg, C.; Nielsen, T.; Hansen, P.E.

    1997-01-01

    Prediction of 1-octanol water partition coefficients for a range of polar N-PAC from HPLC capacity coefficients has been investigated. Two commercially available columns, an ODS column and a Diol column were tested with water-methanol eluents. The best prediction of log K-ow for N-PAC was achieve...... with size and log K-ow for N-PAC was 1.1-1.3 lower than log K-ow for the equivalent PAH. Shielding of the nitrogen atom in the N-PAC compounds caused an increase in log K-ow. (C) 1997 Elsevier Science Ltd....

  18. Glucose-Sensitive Hydrogel Optical Fibers Functionalized with Phenylboronic Acid.

    Science.gov (United States)

    Yetisen, Ali K; Jiang, Nan; Fallahi, Afsoon; Montelongo, Yunuen; Ruiz-Esparza, Guillermo U; Tamayol, Ali; Zhang, Yu Shrike; Mahmood, Iram; Yang, Su-A; Kim, Ki Su; Butt, Haider; Khademhosseini, Ali; Yun, Seok-Hyun

    2017-04-01

    Hydrogel optical fibers are utilized for continuous glucose sensing in real time. The hydrogel fibers consist of poly(acrylamide-co-poly(ethylene glycol) diacrylate) cores functionalized with phenylboronic acid. The complexation of the phenylboronic acid and cis-diol groups of glucose enables reversible changes of the hydrogel fiber diameter. The analyses of light propagation loss allow for quantitative glucose measurements within the physiological range. © 2017 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Boronate-Modified Interdigitated Electrode Array for Selective Impedance-Based Sensing of Glycated Hemoglobin

    DEFF Research Database (Denmark)

    Boonyasit, Yuwadee; Laiwattanapaisal, Wanida; Chailapakul, Orawon

    2016-01-01

    An impedance-based label-free affinity sensor was developed for the recognition of glycated hemoglobin (HbA1c). Interdigitated gold microelectrode arrays (IDA) were first modified with a self-assembled monolayer of cysteamine followed by cross-linking with glutaraldehyde and subsequent binding of 3......-aminophenylboronic acid (APBA), which selectively binds HbA1c via cis-diol interactions. Impedance sensing was demonstrated to be highly responsive to the clinically relevant HbA1c levels (0.1%-8.36%) with a detection limit of 0.024% (3σ). The specificity of the assay was evaluated with non-glycated hemoglobin (Hb...

  20. Rhodococcus erythropolis DCL14 Contains a Novel Degradation Pathway for Limonene

    OpenAIRE

    van der Werf, Mariët J.; Swarts, Henk J.; de Bont, Jan A. M.

    1999-01-01

    Strain DCL14, which is able to grow on limonene as a sole source of carbon and energy, was isolated from a freshwater sediment sample. This organism was identified as a strain of Rhodococcus erythropolis by chemotaxonomic and genetic studies. R. erythropolis DCL14 also assimilated the terpenes limonene-1,2-epoxide, limonene-1,2-diol, carveol, carvone, and (−)-menthol, while perillyl alcohol was not utilized as a carbon and energy source. Induction tests with cells grown on limonene revealed t...

  1. Simultaneous Analysis of 3-MCPD and 1,3-DCP in Asian Style Sauces Using QuEChERS Extraction and Gas Chromatography���Triple Quadrupole Mass Spectrometry

    OpenAIRE

    Genualdi, Susan; Nyman, Patricia; DeJager, Lowri

    2017-01-01

    Acid hydrolyzed vegetable protein (aHVP) is used for flavoring a wide variety of foods and also in the production of nonfermented soy sauce. During the production of aHVP, chloropropanols including 3-monochloropropane-1,2-diol (3-MCPD) and 1,3 dichloropropane-2-ol (1,3-DCP) can be formed through the reaction of the hydrochloric acid catalyst and residual fat and the reaction of 3-MCPD with acetic acid, respectively. 3-MCPD is a carcinogen, and 1,3-DCP has been classified as a genotoxic carcin...

  2. Infant formula and follow-up formula may contain harmful 3-MCPD fatty acid esters

    OpenAIRE

    German Federal Institute for Risk Assessment

    2007-01-01

    Free 3-monochloropropane-1,2-diol (3-MCPD) has been identified as a contaminant for a long time in various foods like liquid seasoning or bakery goods heated to high temperatures. This substance is formed when fat-containing and salt-containing foods are processed at high temperatures during production. In animal experiments 3-MCPD has led to an increase in the cell count (hyperplasia) in renal tubules and, at higher levels, it triggered benign tumours. No genotoxic effect was observed. BfR h...

  3. Occurrence of 3-MCPD fatty acid esters in human breast milk

    OpenAIRE

    2008-01-01

    Abstract A series of twelve breast milks was analysed by GC/MS operated in SIM mode for 3-chloropropane-1,2-diol (3-MCPD). While none of samples contained free 3-MCPD at the level exceeding the method detection limit of (3 g/kg milk), all of them contained high amount of 3-MCPD esterified with higher fatty acids. The levels of 3-MCPD released by hydrolysis of these esters (bound 3-MCPD) ranged from the limit of detection (300 g/kg, expressed on fat basis) to 2195 &#...

  4. VALIDASI MODIFIKASI METODE WEIßHAAR UNTUK ANALISIS 3-MCPD ESTER DALAM MINYAK GORENG SAWIT [Validation of Modified Weißhaar’s Method for 3-MCPD Esters Analysis in Palm Oil

    OpenAIRE

    Tanti Lanovia1,2)*; Nuri Andarwulan1,3); Purwiyatno Hariyadi1,3)

    2014-01-01

    The 3-monochloropropane-1,2-diol (3-MCPD) and 3-MCPD esters were found in any type of refined vegetable oil -mostly produced during the refining process- and recognized as emerging food contaminants. Several analytical methods have been developed and one of which was a Weißhaar's method. The study aims to validate the modified Weißhaar's method for analysis of 3-MCPD and 3-MCPD esters in refined palm oil. Ion fragments were used for identification and quantification of 3-MCPD and 3-MCPD-d5. 3...

  5. ANALISIS 3-MONOKLORO-1,2-PROPANADIOL (3-MCPD) ESTER DALAM MINYAK SAWIT DENGAN INSTRUMEN KROMATOGRAFI GAS-SPEKTROSKOPI MASSA

    OpenAIRE

    Hanifah Nuryani Lioe; Nancy Dewi Yuliana; Dias Indrasti; Yane Regiyana; Cony Arisya Putri

    2015-01-01

    A group of components called as 3-monochloropropane-1,2-diol (3-MCPD) esters has been found in some vegetable oils, particularly palm oil. Analysis of these components needs GC-MS instrument to reach a low level detection, parts per billion or ppb level. An effort to validate the 3-MCPD esters analysis by GC-MS method (Weiβhaar method) using phenyl boronic acid (PBA) as a derivatizing agent and isotopic internal standard (IS) 3-MCPD-D5 followed by the determination of 3-MCPD in commercial pal...

  6. Highly Efficient Procedure for the Synthesis of Fructone Fragrance Using a Novel Carbon based Acid

    Directory of Open Access Journals (Sweden)

    Xuezheng Liang

    2010-08-01

    Full Text Available The novel carbon based acid has been synthesized via one-step hydrothermal carbonization of furaldehyde and hydroxyethylsulfonic acid. A highly efficient procedure for the synthesis of fructone has been developed using the novel carbon based acid. The results showed that the catalyst possessed high activity for the reaction, giving a yield of over 95%. The advantages of high activity, stability, reusability and low cost for a simple synthesis procedure and wide applicability to various diols and β-keto esters make this novel carbon based acid one of the best choices for the reaction.

  7. Proximally functionalized cavitands and synthesis of a flexible hemicarcerand

    NARCIS (Netherlands)

    Timmerman, P.; Boerrigter, H.; Verboom, Willem; van Hummel, G.J.; Harkema, Sybolt; Reinhoudt, David

    1995-01-01

    A general study on the synthesis of partly bridged octols3a-d and4c-d is described. Tri-bridged diol3c can be prepared in 54% yield in DMSO at 70°C with excess CH2BrCl or in 52% yield in DMF at 70°C with only 4 equiv. of CH2BrCl. 1,3-Di-bridged tetrol4a, one of the two possible di-bridged isomers

  8. A New Furostanol Glycoside from Tribulus terrestris

    Directory of Open Access Journals (Sweden)

    Tonghua Liu

    2010-01-01

    Full Text Available Besides two known glycosides, a new furostanol glycoside was isolated from the Fruits of Tribulus terrestris L. The structure of the new furostanol glycoside was established as 26-O-β-D-glucopyranosyl-(25S-5α-furostane-20(22-en-12-one-3β, 26-diol-3-O-α-L-rhamnopyranosyl-(1→2-[β-D-glucopyranosyl-(1→4]-β-D-galactopyranoside (1 on the basis of 1D and 2D-NMR techniques, including COSY, HMBC, and HMQC correlations.

  9. A new furostanol glycoside from Tribulus terrestris.

    Science.gov (United States)

    Xu, Yajuan; Liu, Yonghong; Xu, Tunhai; Xie, Shengxu; Si, Yunshan; Liu, Yue; Zhou, Haiou; Liu, Tonghua; Xu, Dongming

    2010-01-27

    Besides two known glycosides, a new furostanol glycoside was isolated from the Fruits of Tribulus terrestris L. The structure of the new furostanol glycoside was established as 26-O-beta-D-glucopyranosyl-(25S)-5alpha-furostane-20(22)-en-12-one-3beta, 26-diol-3-O-alpha-L-rhamnopyranosyl-(1-->2)-[beta-D-glucopyranosyl-(1-->4)]-beta-D-galactopyranoside (1) on the basis of 1D and 2D-NMR techniques, including COSY, HMBC, and HMQC correlations.

  10. Cyclodextrin ketones as oxidation catalysts: investigation of bridged derivatives

    DEFF Research Database (Denmark)

    Fenger, Thomas Hauch; Marinescu, Lavinia; Bols, Mikael

    2009-01-01

    A series of alpha-cyclodextrin derivatives containing a 3, 4 or 5 membered ether-linked bridge between the 6A and 6D oxygen atoms, with and without a ketone, were prepared. The synthesis used perbenzylated alpha-cyclodextrin A,D-diol as a starting material upon which O-alkylation and further modi...... derivatives were also made. The 6A,6D-di-O-(propa-2-on-1,3-diyl)-6C,6F-di-O-methyl and di-O-pivaloyl derivatives were also prepared. The new compounds were analysed for catalysis of the oxidation of amines and alcohols....

  11. Method of absorbing UF6 from gaseous mixtures in alkamine absorbents

    International Nuclear Information System (INIS)

    Lafferty, R.H.; Smiley, S.H.; Radimer, K.J.

    1976-01-01

    A method is described for recovering UF 6 from gaseous mixtures by absorption in a liquid. The liquid absorbent must have a relatively low viscosity and at least one component of the absorbent is an alkamine having less than 3 carbon atoms bonded to the amino nitrogen, less than 2 of the carbon atoms other than those bonded to the amino nitrogen are free of the hydroxy radical and precipitate the absorbed uranium from the absorbent. At least one component of the absorbent is chosen from the group consisting of ethanolamine, diethanolamine, and 3-methyl-3-amino-propane-diol-1,2

  12. Organic transformations catalyzed by methylrhenium trioxide

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Zuolin [Iowa State Univ., Ames, IA (United States)

    1995-10-06

    Methylrhenium trioxide (MTO), CH3ReO3, was first prepared in 1979. MTO forms stable or unstable adducts with electron-rich ligands, such as amines (quinuclidine, 1,4-diazabicyclo-octane, pyridine, aniline, 2,2'-bipyridine), alkynes, olefins, 1,2-diols, catechols, hydrogen peroxide, water, thiophenols, 1,2-dithiols, triphenylphosphine, 2-aminophenols, 2-aminothiophenols, 8-hydroxyquinoline and halides (Cl-, Br-, I-). After coordination, different further reactions will occur for different reagents. Reactions described in this report include the dehydration of alcohols, direct amination of alcohols, activation of hydrogen peroxide, oxygen transfer, and decomposition of ethyl diazoacetate.

  13. Enhanced dispersion of carbon nanotubes in hyperbranched polyurethane and properties of nanocomposites

    International Nuclear Information System (INIS)

    Rana, Sravendra; Karak, Niranjan; Cho, Jae Whan; Kim, Young Ho

    2008-01-01

    Hyperbranched polyurethane (HBPU) nanocomposites with multi-walled carbon nanotubes (MWNTs) were prepared by in situ polymerization on the basis of poly(ε-caprolactone)diol as the soft segment, 4,4'-methylene bis(phenylisocyanate) as the hard segment, and castor oil as the multifunctional group for the hyperbranched structure. A dominant improvement in the dispersion of MWNTs in the HBPU matrix was found, and good solubility of HBPU-MWNT nanocomposites in organic solvents was shown. Due to the well-dispersed MWNTs, the nanocomposites resulted in achieving excellent shape memory properties as well as enhanced mechanical properties compared to pure HBPU.

  14. Synthesis of the Demospongic Compounds, (6Z, 11Z-Octadecadienoic Acid and (6Z, 11Z-Eicosadienoic Acid

    Directory of Open Access Journals (Sweden)

    V. R. Mamdapur

    1997-01-01

    Full Text Available A stereoselective synthesis of (6Z, 11Z-octadecadienoic acid (1 and (6Z, 11Z-eicosadienoic acid (2 from easily accessible pentane-1,5-diol (3 is described. Thus, compound 3 on pyranylation and oxidation gave the aldehyde 5 which was converted to the acid 7 by Wittig reaction with a suitable phosphorane. Its depyranylation and oxidation furnished the key aldehyde 9 which upon Wittig reaction with n-heptylidene and n-nonylidene phosphoranes, respectively followed by alkaline hydrolysis afforded the title acids.

  15. The synthesis of benzimidazoles and quinoxalines from aromatic diamines and alcohols by iridium-catalyzed acceptorless dehydrogenative alkylation.

    Science.gov (United States)

    Hille, Toni; Irrgang, Torsten; Kempe, Rhett

    2014-05-05

    Benzimidazoles and quinoxalines are important N-heteroaromatics with many applications in pharmaceutical and chemical industry. Here, the synthesis of both classes of compounds starting from aromatic diamines and alcohols (benzimidazoles) or diols (quinoxalines) is reported. The reactions proceed through acceptorless dehydrogenative condensation steps. Water and two equivalents of hydrogen are liberated in the course of the reactions. An Ir complex stabilized by the tridentate P^N^P ligand N(2) ,N(6) -bis(di-isopropylphosphino)pyridine-2,6-diamine revealed the highest catalytic activity for both reactions. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Bidirectional cross metathesis and ring-closing metathesis/ring opening of a C 2-symmetric building block: a strategy for the synthesis of decanolide natural products.

    Science.gov (United States)

    Schmidt, Bernd; Kunz, Oliver

    2013-01-01

    Starting from the conveniently available ex-chiral pool building block (R,R)-hexa-1,5-diene-3,4-diol, the ten-membered ring lactones stagonolide E and curvulide A were synthesized using a bidirectional olefin-metathesis functionalization of the terminal double bonds. Key steps are (i) a site-selective cross metathesis, (ii) a highly diastereoselective extended tethered RCM to furnish a (Z,E)-configured dienyl carboxylic acid and (iii) a Ru-lipase-catalyzed dynamic kinetic resolution to establish the desired configuration at C9. Ring closure was accomplished by macrolactonization. Curvulide A was synthesized from stagonolide E through Sharpless epoxidation.

  17. Antiproliferative Compounds of Cyphostemma greveana from a Madagascar Dry Forest[1

    OpenAIRE

    Cao, Shugeng; Hou, Yanpeng; Brodie, Peggy; Miller, James S.; Randrianaivo, Richard; Rakotobe, Etienne; Rasamison, Vincent E.; Kingston, David G. I.

    2011-01-01

    Bioassay-guided fractionation of the EtOH extracts obtained from a plant identified as Cyphostemma greveana Desc. (Vitaceae) led to the identification of one macrolide, lasiodiplodin (1), three sesquiterpenoids, 12-hydroxy-15-oxo-selina-4,1l-diene (2), 1β,6α-dihydroxyeudesm-4(15)-ene (3), and (7R*)-opposit-4(15)-ene-1β,7-diol (5), and the new diterpenoid, 16,18-dihydroxykolavenic acid lactone (4). All the isolates were tested against the A2780 human ovarian cancer cell line, and compound 4 an...

  18. Steroids from the Brazilian Zoanthids Palythoa caribaeorum and Palythoa variabilis

    OpenAIRE

    Pinto, Francisco C. L.; Almeida, José Gustavo L.; Silveira, Edilberto R.; Costa, Arinice M.; Guimarães, Larissa A.; Wilke, Diego V.; Costa-Lotufo, Letícia V.; Torres, Maria da Conceição M.; Pessoa, Otília Deusdênia L.

    2017-01-01

    Two unreported ergostane-type sterols 24(R)-7α-hydroperoxy-ergost-5-en-3β-ol and 6β-carboxyl-24(R)-(8→6)-abeo-ergostan-3β,5β-diol, along with seven known ones were isolated from the hexane and alcohol extracts from the zoanthids Palythoa caribaeorum and Palythoa variabilis. The structures of the new compounds were determined using spectroscopic techniques, including 1D and 2D nuclear magnetic resonance (NMR), high-resolution electrospray ionization mass spectrom...

  19. Photometric method to determining boron microamounts in the form of β-diketonate complex in steel and alloys bsed on nickel

    International Nuclear Information System (INIS)

    Ishchenko, A.V.; Stashkova, N.V.; Timoteus, Kh.R.; Fedorova, S.F.

    1988-01-01

    A sensitive technique of determining boron microamounts in steels and alloys based on nickel, doped with chromium, tungsten, molybdenum, titanium and vanadium is developed. After boron preextraction by β-diol chloroform solutions its determination is carried out directly in organic phase in acidic and sulfuric acids by β-diketone class reagent: 4,4'-dihydroxydibensoylmethane (I) or 4,4'-dimethoxydibenzoylmethane. Molar light-absorption coefficient for reagent I at formation of boroxalate complex is 8.48x10 4 , at of complexing in presence of sulfuric acid -10.63x10 4 , of acetic acid-17.27x10 4

  20. 3' end labelling of RNA with /sup 32/P suitable for rapid gel sequencing

    Energy Technology Data Exchange (ETDEWEB)

    Winter, G; Brownlee, G G [Medical Research Council, Cambridge (UK)

    1978-09-01

    A new general method of labelling the 2', 3'-diol end of RNA with /sup 32/P has been devised suitable for gel sequencing. Poly(A) polymerase (E.coli) is incubated with the RNA and limiting amounts of ..cap alpha..-/sup 32/P-ATP. The mono-addition product is then cleaved with periodate and ..beta..-eliminated with aniline, leaving the RNA terminally labelled with 3'/sup 32/P-phosphate. When applied to a model compound, tRNAsup(Phe) from E. coli, over 28 residues could be read from the 3' end.