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Sample records for pyrans

  1. Synthesis of Polyfunctionalized 4H-Pyrans

    Directory of Open Access Journals (Sweden)

    Manisha Bihani

    2013-01-01

    Full Text Available Amberlyst A21 catalyzed one-pot three-component coupling of aldehyde and malononitrile with active methylene compounds such as acetylacetone and ethyl acetoacetate for the synthesis of pharmaceutically important polyfunctionalized 4H-pyrans has been reported. Simple experimental procedure, no chromatographic purification, no hazardous organic solvents, easy recovery and reusability of the catalyst, and room temperature reaction conditions are some of the highlights of this protocol for the synthesis of pharmaceutically relevant focused libraries.

  2. Synthesis of fused pyran and arylbis(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)methane in ionic liquid

    Institute of Scientific and Technical Information of China (English)

    Xue Sen Fan; Ying Ying Qu; Xin Ying Zhang; Xia Wang; Jian Ji Wang

    2009-01-01

    Promoted and mediated by an ionic liquid-[bmim][BF4].fused pyrans or arylbis(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)methanes were efficiently and selectively prepared from the reaction of aldehyde and 4-hydroxy-6-methyl-2-oxo-pyran with or Without acetic anhydride.By using these novel procedures,pyrimidine nucleoside-fused pyran and arylbis(pyranon-3-yl)methane hybrids with potential biological activities were constructed.

  3. Synthesis of novel photochromic pyrans via palladium-mediated reactions

    NARCIS (Netherlands)

    Böttcher, Christoph; Zeyat, Gehad; Ahmed, Saleh A.; Irran, Elisabeth; Cordes, Thorben; Elsner, Cord; Zinth, Wolfgang; Rueck-Braun, Karola

    2009-01-01

    Photochromic pyrans for applications in material and life sciences were synthesized via palladium-mediated cyanation, carbonylation and Sonogashira cross-coupling starting from a bromo-substituted naphthopyran and benzopyrans. A novel photoswitchable benzopyran-based ω-amino acid for Fmoc-based soli

  4. Enzymology of Pyran Ring A Formation in Salinomycin Biosynthesis.

    Science.gov (United States)

    Luhavaya, Hanna; Dias, Marcio V B; Williams, Simon R; Hong, Hui; de Oliveira, Luciana G; Leadlay, Peter F

    2015-11-09

    Tetrahydropyran rings are a common feature of complex polyketide natural products, but much remains to be learned about the enzymology of their formation. The enzyme SalBIII from the salinomycin biosynthetic pathway resembles other polyether epoxide hydrolases/cyclases of the MonB family, but SalBIII plays no role in the conventional cascade of ring opening/closing. Mutation in the salBIII gene gave a metabolite in which ring A is not formed. Using this metabolite in vitro as a substrate analogue, SalBIII has been shown to form pyran ring A. We have determined the X-ray crystal structure of SalBIII, and structure-guided mutagenesis of putative active-site residues has identified Asp38 and Asp104 as an essential catalytic dyad. The demonstrated pyran synthase activity of SalBIII further extends the impressive catalytic versatility of α+β barrel fold proteins.

  5. Pyran-2-one Derivatives from the Roots of Croton crassifolius.

    Science.gov (United States)

    Huang, Weihuan; Wang, Jiajian; Liang, Yeyin; Li, Yaolan; Wang, Guocai

    2016-06-01

    One new pyran-2-one derivative [crotonpyrone C (1)] and two known ones (2-3) were isolated from the supercritical fluid extract (SFE) of the roots of Croton crassifolius. Their structures were elucidated using spectroscopic (IR, UV, 1D and 2D NMR) and HRESIMS methods. The isolated compounds were evaluated for their anti-angiogenic activity using a zebrafish model, but showed little activity.

  6. Synthesis of novel photochromic pyrans via palladium-mediated reactions

    Directory of Open Access Journals (Sweden)

    Christoph Böttcher

    2009-05-01

    Full Text Available Photochromic pyrans for applications in material and life sciences were synthesized via palladium-mediated cyanation, carbonylation and Sonogashira cross-coupling starting from bromo-substituted naphthopyran 1 and benzopyrans 2a/b. A novel photoswitchable benzopyran-based ω-amino acid 6 for Fmoc-based solid-phase peptide synthesis is presented. The photochromic behaviour of the 3-cyano-substituted benzopyran 5a was investigated by time-resolved absorption spectroscopy in the picosecond time domain.

  7. Crystal structure of di-bromo-meth-oxy-seselin (DBMS), a photobiologically active pyran-ocoumarin.

    Science.gov (United States)

    Bauri, A K; Foro, Sabine; Rahman, A F M M

    2017-05-01

    The title compound, C15H14Br2O4 [systematic name: rac-(9S,10R)-3,9-dibromo-10-methoxy-8,8-dimethyl-9,10-dihydropyrano[2,3-h]chromen-2(8H)-one], is a pyran-ocoumarin derivative formed by the bromination of seselin, which is a naturally occurring angular pyran-ocoumarin isolated from the Indian herb Trachyspermum stictocarpum. In the mol-ecule, the benzo-pyran ring system is essentially planar, with a maximum deviation of 0.044 (2) Å for the O atom. The di-hydro-pyran ring is in a half-chair conformation and the four essentially planar atoms of this ring form a dihedral angle of 4.6 (2)° with the benzo-pyran ring system. In the crystal, mol-ecules are linked by weak C-H⋯O hydrogen bonds, forming chains propagating along [010]. In addition, π-π stacking inter-actions, with centroid-centroid distances of 3.902 (2) and 3.908 (2) Å, link the hydrogen-bonded chains into layers parallel to (001).

  8. One-Pot Synthesis of Tetrahydrobenzo-[b]-pyran Derivatives in Aqueous Media

    Institute of Scientific and Technical Information of China (English)

    JIN,Tong-Shou; WANG,Ai-Qing; ZHANG,Jian-She; LI,Tong-Shuang

    2004-01-01

    @@ In modem organic chemical research, 4H-benzo-[b]-pyran and their derivatives have attracted strong interest due to their useful biological and pharmacological properties. Herein, we report a clean one-pot synthesis of 2-amino-3-cyano-4-aryl-7,7-dimethyl-5-oxo-4H-5,6,7,8-tetrahydro-benzo-[b]-pyrans from aromatic aldehyde, malononitrile and 5,5-dimethyl-1,3-cyclohexadione using hexadecyl trimethyl ammonium bromide (HTMAB) as the catalyst. This method provides several advantages such as high yield, simple work-up procedure and environmental friendliness. All the products were characterized by 1H NMR and IR analyses.

  9. Convergent assembly of highly potent analogues of bryostatin 1 via pyran annulation: bryostatin look-alikes that mimic phorbol ester function.

    Science.gov (United States)

    Keck, Gary E; Kraft, Matthew B; Truong, Anh P; Li, Wei; Sanchez, Carina C; Kedei, Noemi; Lewin, Nancy E; Blumberg, Peter M

    2008-05-28

    Highly potent bryostatin analogues which contain the complete bryostatin core structure have been synthesized using a pyran annulation approach as a key strategic element. The A ring pyran was assembled using a pyran annulation reaction between a C1-C8 hydroxy allylsilane and an aldehyde comprising C9-C13. This pyran was transformed to a new hydroxy allylsilane and then coupled with a preformed C ring aldehyde subunit in a second pyran annulation, with concomitant formation of the B ring. This tricyclic intermediate was elaborated to bryostatin analogues which displayed nanomolar to subnanomolar affinity for PKC, but displayed properties indistinguishable from a phorbol ester in a proliferation/attachment assay.

  10. Antimicrobial activity of new 4,6-disubstituted pyrimidine, pyrazoline, and pyran derivatives.

    Science.gov (United States)

    Ramiz, Mahmoud M M; El-Sayed, Wael A; El-Tantawy, Asmaa I; Abdel-Rahman, Adel A-H

    2010-05-01

    A number of new 2,6-didisubstituted pyrimidine, pyrazoline, and pyran derivatives were synthesized starting from their chalcone derivative. The synthesized compounds displayed different degrees of antimicrobial activity against Bscillus subtilis (Gram-positive), Pseudomonas aeruginosa (Gram-negative), and Streptomyces species (Actinomycetes).

  11. ETM and ANN study for polysubstituted 2H-pyran-2-ones.

    Science.gov (United States)

    Saracoglu, Murat; Basaran, Murat Alper; Thul, Pallavi; Sayiner, Hakan; Kandemirli, Sedat Giray; Gupta, Ved Prakash; Kandemirli, Fatma

    2013-09-01

    The structure glutamate pyruvate transaminase (GPT), glutamate oxaloacetate transaminase (GOT), acid phosphatase (ACP), alkaline phosphatase (ALP) and glutamate dehydrogenase (GlDH) activity relationships of 2H-pyran-2- ones polysubstitutes being a new class of hepatoprotective agents have been investigated by means of the Electronic- Topological Method (ETM) and two Statistical Analysis. Molecular fragments specific for active compounds were calculated for 2H-pyran-2-ones polysubstitutes by applying the ETM. QSAR descriptors such as molecular weight, EHOMO, ELUMO, ΔE, chemical potential, softness, electrophilicity index, dipole moment, etc were calculated. In order to examine the relationship between independent and dependent variables, both Partial Least Squares Regression and ANNs are employed to determine the relationship since the data set consists of highly nonlinearity and multicolinearity. It is observed that ANN has surpassed both PLS2 and PLS1 in terms of better modeling and validation.

  12. Optically active 6-acetyloxy-2H-pyran-3(6H)-one obtained by lipase catalyzed transesterification and esterification

    NARCIS (Netherlands)

    van den Heuvel, M.; Cuiper, A.D; van der Deen, H.; Kellogg, R.M; Feringa, B.L.

    1997-01-01

    Kinetic resolution of 6-acetyloxy-2H-pyran-3(6H)-one (1) is achieved by immobilized lipase PS on Hyflo Super Cell in organic solvents. Transesterification in hexane/n-butanol yields enantiomerically pure R-(-)-6-acetyloxy-2H-pyran-3(6H)-one, whereas esterification of 6-hydroxy-2H-pyran-3(6H)-one (2)

  13. An efficient three-step synthesis of cyclopenta[b]pyrans via 2-donor-substituted fischer ethenylcarbenechromium complexes.

    Science.gov (United States)

    de Meijere, Armin; Schirmer, Heiko; Stein, Frank; Funke, Frank; Duetsch, Michael; Wu, Yao-Ting; Noltemeyer, Mathias; Belgardt, Thomas; Knieriem, Burkhard

    2005-07-04

    A wide range of cyclopenta[b]pyrans 4 has been synthesized in a one-pot reaction by treatment of different 2-donorsubstituted ethenylcarbenechromium complexes 2 with alkynes in THF in moderate to excellent yields (41-90 % for 14 out of 25 examples). The starting materials 2 are readily available in good to excellent yields (76-99 % for 25 out of 36 examples) by Michael addition of amines, alcohols and thiols, respectively, to the corresponding alkynylcarbenechromium complexes 1. Due to their 10 pi-electrons in a cross-conjugated bicyclic system, cyclopenta[b]pyrans have been termed pseudoazulenes, as they indeed have similar UV/Vis-spectroscopic properties.

  14. (E-4-Hydroxy-6-methyl-3-[1-(2-phenylhydrazinylideneethyl]-2H-pyran-2-one

    Directory of Open Access Journals (Sweden)

    Samra Rahmouni

    2016-05-01

    Full Text Available The title compound, C14H14N2O3, crystallized with three crystallographically independent molecules (A, B and C in the asymmetric unit. The three molecules each have an E conformation about the C=N bond but differ in the orientation of the phenyl and pyran rings. The dihedral angles between the phenyl and pyran ring planes are 14.30 (1, 28.38 (1 and 25.58 (1° in molecules A, B and C, respectively. There is an intramolecular O—H...N hydrogen bond in each molecule with an S(6 ring motif. In the crystal, molecules are linked by N—H...O and C—H...O hydrogen bonds, forming layers parallel to (001, enclosing R22(8 and R33(21 ring motifs. The layers are linked via C—H...π interactions, forming bilayers, which are joined by a further C—H...π interaction, forming a three-dimensional structure.

  15. Temperature dependence of (+)-catechin pyran ring proton coupling constants as measured by NMR and modeled using GMMX search methodology

    Science.gov (United States)

    Fred L. Tobiason; Stephen S. Kelley; M. Mark Midland; Richard W. Hemingway

    1997-01-01

    The pyran ring proton coupling constants for (+)-catechin have been experimentally determined in deuterated methanol over a temperature range of 213 K to 313 K. The experimental coupling constants were simulated to 0.04 Hz on the average at a 90 percent confidence limit using a LAOCOON method. The temperature dependence of the coupling constants was reproduced from the...

  16. pyran Derivatives

    African Journals Online (AJOL)

    NICO

    supported ... various organic transformations such as oxidation, dehydro- genation .... precipitate was next washed with distilled water and acetone. The product ... was stirred for 5–10 min before been treated with dimedone. (1 mmol) and ...

  17. Prins fluorination cyclisations: Preparation of 4-fluoro-pyran and -piperidine heterocycles

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    Guillaume G. Launay

    2010-04-01

    Full Text Available The Prins reaction was investigated using BF3·OEt2 as a Lewis acid. It has been recently demonstrated, that if BF3·OEt2 is used in stoichiometric amounts then these reactions generate fluorinated products where the BF3·OEt2 contributes fluoride ion to quench the intermediate carbocations. In this study oxa- and aza-Prins reactions for the synthesis of 4-fluoro-pyrans and -piperidines were investigated. The products were obtained in good yields, but only with moderate diastereoselectivity. These Prins fluorination reactions can be accelerated under microwave conditions. The study extends the Prins fluorination methodology for the generation of the C–F bond in heterocycles.

  18. Condensation Reaction of 5, 6-Dihydro-6-methyl-6-piperonyl-2H- pyran-2,4-dione, Ethyl Orthoformate and Substituted Anilines

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Piperonyl methyl ketone was obtained by oxidizing isosafrole with hydrogen peroxide and formic acid. Dianion of ethyl acetoacetate reacted with piperonyl methyl ketone and 5, 6-dihydro-6-methyl-6-piperonyl-2H-pyran-2, 4-dione was prepared, which reacted with substituted anilines in the presence of ethyl orthoformate to obtain 3-anilinomethylene-5, 6- dihydro- 6-methyl-6-piperonyl-2H-pyran-2, 4-diones. Their structures were confirmed by 1HNMR and elemental analysis.

  19. Snail shell as a new natural and reusable catalyst for synthesis of 4H-Pyrans derivatives

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    Zakaria Benzekri

    2016-07-01

    Full Text Available A simple, efficient and general method for the synthesis of 4H-pyrans is established through a multi component cyclocondensation of aromatic aldehydes, malononitrile and ethyl acetoacetate or acetyl acetone using snail shell as a natural catalyst. In this method the snail shell was used as green and reusable natural catalyst. Excellent yields, short reaction times and availability of the catalyst are the advantages of this method.

  20. 6-Pentyl-2H-pyran-2-one: a potent peach-derived kairomone for New Zealand flower thrips, Thrips obscuratus.

    Science.gov (United States)

    El-Sayed, A M; Mitchell, V J; Suckling, D M

    2014-01-01

    New Zealand flower thrips, Thrips obscuratus (Thysanoptera: Thripidae), are attracted to ripening fruits, especially peaches. Volatiles from unripe and ripe peach fruits were collected and analyzed by gas chromatography/mass spectrometry. Six lactones were found only in ripe peach volatiles: γ-heptalactone, γ-octalactone, γ-nonalactone, 6-pentyl-2H-pyran-2-one, γ-decalactone, and δ-decalactone. When these compounds were tested individually in field-trapping experiments, three of them (γ-octalactone, γ-nonalactone, and 6-pentyl-2H-pyran-2-one) attracted New Zealand flower thrips. In another field-trapping experiment, aimed at testing various combinations of the three active compounds, no synergistic effects were found among all combinations tested; no combination caught more thrips than 6-pentyl-2H-pyran-2-one, alone. A further field-trapping experiment was conducted to determine the dose (10, 100, and 500 mg) of 6-pentyl-2H-pyran-2-one that gave the greatest catch of T. obscuratus, while also comparing it against another attractant, ethyl nicotinate, for T. obscuratus. The greatest catches in traps baited with either attractant were at loadings of 500 mg. At both 10 and 500 mg, traps baited with 6-pentyl-2H-pyran-2-one caught more T. obscuratus than those baited with the same amounts of ethyl nicotinate. 6-Pentyl-2H-pyran-2-one is a potent attractant for New Zealand flower thrips and, therefore, could be used for monitoring and control of New Zealand flower thrips. Work is underway developing monitoring and control options utilizing 6-pentyl-2H-pyran-2-one for this important pest.

  1. NEW PYRAN OF AN ENDOPHYTIC FUNGUS Fusarium sp. ISOLATED FROM THE LEAVES OF BROTOWALI (Tinaspora crispa

    Directory of Open Access Journals (Sweden)

    Elfita Elfita

    2013-12-01

    Full Text Available Endophytes are microorganisms that reside asymptomatically in the tissues of higher plants and are relatively unstudied and a promising source of novel organic natural metabolites exhibiting a variety of biological activities. As a part of our systematic search for new bioactive lead structures from endophytic, the endophytic fungus Fusarium sp. isolated from the leaves of Brotowali (Tinaspora crispa, was cultured for isolation of metabolite. The endophytic fungus was cultivated on 6 L of Potatos Dextose Broth (PDB medium at room temperature (no shaking for 8 weeks. The cultures were then extracted with ethyl acetate to afford 9.4 g of residue after removal of the solvent under reduced pressure. The extract was separated into the fractions by column chromatography (CC on silica gel. The fractions were further separated by silica gel column chromatography to give one compound. The molecular structure was established on the basis of spectroscopic analysis including UV, IR, 1H-NMR, 13C-NMR, HMQC, HMBC, COSY, and MS. The compound was determined as a new pyran.

  2. Crystal structure of a photobiologically active brominated angular pyran-ocoumarin: bromo-hy-droxy-seselin.

    Science.gov (United States)

    Bauri, A K; Foro, Sabine; Rahman, A F M Mustafizur

    2017-03-01

    The title compound, C14H13BrO3 [systematic name: rac-(9S,10R)-9-bromo-10-hy-droxy-8,8-dimethyl-9,10-di-hydro-2H,8H-pyrano[2,3-f]chromen-2-one], is a substituted pyran-ocoumarin, obtained by bromination of seselin [8,8-dimethyl-2H,8H-pyrano[2,3-f]chromen-2-one], which was isolated from the Indian herb Trachyspermum stictocarpum (Aajmod). The pyrano ring has a distorted half-chair conformation and its mean plane is inclined to the coumarin mean plane by 1.6 (2)°. In the crystal, mol-ecules are linked by pairs of O-H⋯O hydrogen bonds, forming inversion dimers with an R(2)2(16) ring motif. The dimers stack along the a-axis direction and are linked by offset π-π inter-actions, forming columns [inter-centroid distance = 3.514 (4) Å].

  3. An Efficient and Green Synthesis of 5-Oxo-5,6,7,8-tetrahydro 4H-benzo-[b]-pyran Derivatives Promoted by InCl3·4H2O Under Microwave Irradiation

    Institute of Scientific and Technical Information of China (English)

    Xue Yuan HU; Xue Sen FAN; Xin Ying ZHANG; Gui Rong QU; Yan Zhen LI

    2005-01-01

    A rapid and facile preparation of benzo-[b]-pyran derivatives through condensation of chalcone and 5, 5-dimethyl-1,3-cyclohexandione under microwave irradiation in the presence of simplicity and environmental benignancy, this method may provide a useful alternative for the preparation of benzo-[b]-pyran derivatives.

  4. Ethyl 2,2-dimethyl-4-oxo-6-phenyl-3,4-dihydro-2H-pyran-5-carboxylate

    Directory of Open Access Journals (Sweden)

    N. Sharmila

    2016-12-01

    Full Text Available The title compound, C16H18O4, is a derivative of 3,4-dihydro-2H-pyran-4-one. The plane of the pyranone ring system forms a dihedral angle of 42.76 (10° with that of the phenyl group. The crystal structure is stabilized by C—H...O interactions that enclose an R21(6 ring motif and link the molecules into chains along the c axis. A short intramolecular O...O contact [2.942 (3 Å] gives rise to an S(5 motif.

  5. Synthesis and transformations of 4-chromene 4-hydroxy-2-pyran-2-one and 4-chromene 4-hydroxycoumarin conjugates

    Indian Academy of Sciences (India)

    H Surya Prakash Rao; Venkata Swamy Tangeti

    2013-07-01

    The reaction of -methyl-4-(methylthio)-3-nitro-4-chromen-2-amine and its derivatives with 4-hydroxy-6-methyl-2-pyran-2-one in EtOH reflux for 5 min furnish 4-hydroxy-6-methyl-3-(2-(methylamino)-3-nitro-4-chromen-4-yl)-2-pyran-2-ones in quantitative yield. By extending EtOH reflux for 2 h, the 4-chromene 4-hydroxy-2-pyranone conjugates get converted into acetoacetyl coumarins. Similar reaction of -methyl-4-(methylthio)-3-nitro-4-chromen-2-amine and its derivatives with 4-hydroxycoumarin in EtOH reflux furnish 4-hydroxy-2'-(methylamino)-3'-nitro-2,4'-3,4'-bichromen-2-ones. In contrast to earlier system, prolonging reflux in EtOH or in -PrOH reflux the product gets transformed into trans-ethyl 3-(2-hydroxyaryl)-4-oxo-3,4-dihydro-2-furo[3,2-c]chromene-2-carboxylates. Thus, facile synthesis and characterization of 4-chromene 4-hydroxy-2-pyrone, 4-chromene 4-hydroxycoumarin conjugates, acetoacetyl coumarins and trans2,3-disubstituted dihydrofuro[3,2-c]coumarins is described.

  6. Sodium alginate: An efficient biopolymeric catalyst for green synthesis of 2-amino-4H-pyran derivatives.

    Science.gov (United States)

    Dekamin, Mohammad G; Peyman, S Zahra; Karimi, Zahra; Javanshir, Shahrzad; Naimi-Jamal, M Reza; Barikani, Mehdi

    2016-06-01

    Sodium alginate, a naturally occurring macromolecule, in its granular form and without any post-modification was found to be an efficient and recoverable bifunctional heterogeneous organocatalyst for the domino synthesis of various 2-amino-3-cyano-4H-pyran annulated derivatives through three-component condensation of different aldehydes, malononitrile and diverse 1,3-dicarbonyl compounds under mild conditions. Corresponding 4H-pyran derivatives were obtained in high to excellent yields after 25-150min stirring in 2mL EtOH under reflux conditions in the presence of 10mol% of sodium alginate, equimolar amounts of aldehydes, malononitrile and 1,3-dicarbonyl compounds. The catalyst was easily separated from the reaction mixture to obtain desired products in excellent purity as shown by FTIR and (1)H NMR spectroscopic methods. Avoiding the use of any transition metal, one-pot and multi-component procedure catalyzed by a renewable biopolymer, the reusability of the catalyst, broad substrate scope and operational simplicity are important features of this methodology for preparation of medicinally important compounds. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Replacement of the Bryostatin A- and B-Pyran Rings With Phenyl Rings Leads to Loss of High Affinity Binding With PKC.

    Science.gov (United States)

    Petersen, Mark E; Kedei, Noemi; Lewin, Nancy E; Blumberg, Peter M; Keck, Gary E

    2016-10-19

    We describe a convergent synthesis of a bryostatin analogue in which the natural A- and B-ring pyrans have been replaced by phenyl rings. The new analogue exhibited PMA like behavior in cell assays, but failed to maintain high affinity binding for PKC, despite retaining an unaltered C-ring 'binding domain'.

  8. One-pot three-component synthesis of tetrahydrobenzo[b]pyrans catalyzed by cost-effective ionic liquid in aqueous medium☆

    Institute of Scientific and Technical Information of China (English)

    Jianguo Yang; Shuo Liu; Huanan Hu; Shibin Ren; Anguo Ying

    2015-01-01

    A simple and efficient method is proposed for the synthesis of tetrahydrobenzo[b]pyrans with aromatic alde-hydes, active methylene compounds, and dimedone using basic ionic liquid catalyst in water. The procedure offers several advantages including short reaction time, good yield, easy procedure, and good recyclability of catalysts, which may be a practical alternative to conventional processes for preparation of 4-hpyrans.

  9. Novel and Efficient Method for The Synthesis of 4-Chloro-5, 6-Dihydro Pyran Derivatives using Lewis Acidic Chloroaluminate Ionic Liquids

    Directory of Open Access Journals (Sweden)

    N. Maruthi Raju

    2016-08-01

    Full Text Available The reaction of aldehydes/ketones with homopropargylic alcohols in the presence of 1-n-Butyl-3-methylimidazolium chloroaluminate [bmim]Cl·AlCl3 (N = 0.56-0.67 ionic liquid generates the 4-chloro-5,6-dihydro-2H-pyran derivatives in excellent yield and in short reaction times.

  10. Genotoxicity evaluation of two kinds of smoke-water and 3,7-dimethyl-2H-furo[2,3-c]pyran-2-one.

    Science.gov (United States)

    Trinh, Cécile; Gevaert, Lieven; Kohout, Ladislav; Van Staden, Johannes; Verschaeve, Luc

    2010-08-01

    Smoke, smoke-water and aerosols have a stimulatory effect on seed germination and growth vigour of many seedlings, making them potentially useful for different purposes, provided they do not pose a health risk. Therefore, the genotoxicity of two kinds of smoke-water and 3,7-dimethyl-2H-furo[2,3-c]pyran-2-one, a variant of the most active smoke compound (3-methyl-2H-furo[2,3-c]pyran-2-one) was evaluated using the Vitotox assay. Smoke-water extracts were obtained from burning leaves: Themeda triandra (smoke-water Tt) and a mix of Themeda triandra and Passerina vulgaris (smoke-water Kb). No genotoxic effect was observed for any of the three samples. However, the three samples are toxic at the highest concentrations (3,7-dimethyl-2H-furo[2,3-c]pyran-2-one, 2 ppm; smoke-water Tt, dilutions 1 : 1, 1 : 2, 1 : 4; smoke-water Kb, dilution 1 : 1) without addition of S9 mix. Both the butenolide 3,7-dimethyl-2H-furo[2,3-c]pyran-2-one and smoke-water Tt are also toxic at high doses in the presence of S9 (2 ppm and dilutions 1 : 1 and 1 : 2, respectively), but not smoke-water Kb. Thus, from these results, no genotoxicity of these three samples can be assumed, which is accordance with the previous tests performed with 3-methyl-2H-furo[2,3-c]pyran-2-one and a smoke-water.

  11. Synthesis of 6-Substituted 2-Pyrones Starting from Renewable Resources: Total Synthesis of Sibirinone, (E)-6-(Pent-1-en-1-yl)-2H-pyran-2-one, and (E)-6-(Hept-1-en-1-yl)-2H-pyran-2-one.

    Science.gov (United States)

    Dobler, Daniel; Reiser, Oliver

    2016-11-04

    An atom-economic reaction sequence to 6-substituted 2-pyrones was developed starting from furfuryl alcohol, a renewable resource made from bran or bagasse, and aldehydes, utilizing a thermal rearrangement of cyclopentadienone epoxides as key step. Derivatives bearing a hydroxyalkyl side chain could be enzymatically resolved, providing access to enantiomerically pure 2-pyrones, or converted to alkenyl-substituted 2-pyrones such as naturally occurring sibirinone, (E)-6-(pent-1-en-1-yl)-2H-pyran-2-one, and (E)-6-(hept-1-en-1-yl)-2H-pyran-2-one.

  12. Silica-bonded N-propylpiperazine sodium n-propionate as recyclable catalyst for synthesis of 4H-pyran derivatives

    Institute of Scientific and Technical Information of China (English)

    Khodabakhsh Niknam; Nassim Borazjani; Reza Rashidian; Abbas Jamali

    2013-01-01

    Silica-bonded N-propylpiperazine sodium n-propionate (SBPPSP) was found to act as an efficient solid base for the preparation of a series of 4H-benzo[b]pyran derivatives. SBPPSP was used as a recyclable heterogeneous solid base catalyst for the synthesis of 3,4-dihydropyrano[c]chromenes, 2-amino-4H-pyrans, 1,4-dihydropyrano[2,3-c]pyrazoles, and 2-amino-4H-benzo[e]-chromenes via the condensation reaction of dimedone, ethyl acetoacetate, 3-methyl-1-phenyl-1H-pyrazol-5(4H)-one, andα-naphthol, respectively, with aromatic aldehydes and malononitrile in refluxing aqueous ethanol. The heterogeneous solid base showed similar efficiency when reused in consecutive reac-tions.

  13. Diastereoselective synthesis of 3,4-dihydro-2H-pyran-4-carboxamides through an unusual regiospecific quasi-hydrolysis of a cyano group

    Directory of Open Access Journals (Sweden)

    Mikhail Yu. Ievlev

    2016-09-01

    Full Text Available An efficient diastereoselective approach for the synthesis of functionalized 3,4-dihydro-2H-pyran-4-carboxamides with variable frame was developed based on the reaction of available 4-oxoalkane-1,1,2,2-tetracarbonitriles (adducts of TCNE and ketones with aldehydes in an acidic media. An unusual process of quasi hydrolysis of the cyano group was observed in the course of the described regio- and diastereoselective transformation.

  14. PbO as an efficient and reusable catalyst for one-pot synthesis of tetrahydro benzo pyrans and benzylidene malonitriles

    Indian Academy of Sciences (India)

    Ashok V Borhade; Bhagwat K Uphade; Dipak R Tope

    2013-05-01

    PbO nanoparticles have been employed as an efficient catalyst for the solvent-free synthesis of tetrahydrobenzo pyrans (yields 81-91%) and benzylidene malonitriles (yields 90-96%) at room temperature using green chemistry approach. PbO nanoparticles were found to be highly efficient, eco-friendly and recyclable heterogeneous catalyst. PbO nanoparticles were prepared by hydrothermal method and characterized by IR, XRD, BET Surface area, SEM, EDAX and TEM with SAED techniques.

  15. An efficient one-pot three-component synthesis of tetrahydrobenzo[b]pyran and 3,4-dihydropyrano[c]chromene derivatives using starch solution as catalyst

    Institute of Scientific and Technical Information of China (English)

    Nourallah Hazeri; Malek Taher Maghsoodlou; Fatemeh Mir; Mehrnoosh Kangani; Hamideh Saravani; Ebrahim Molashahi

    2014-01-01

    Tetrahydrobenzo[b]pyran and 3,4-dihydropyrano[c]chromene derivatives were synthesized via a one-pot three-component condensation of aromatic aldehydes with malononitrile and dimedone or 4-hydroxycoumarin in excellent yields in the presence of starch solution as a highly efficient ho-mogenous catalyst. The use of a nontoxic and biodegradable catalyst, simple work-up procedure, and short reaction time are advantages of this method.

  16. Computational assessment of the electronic structures of cyclohexa-1,2,4-triene, 1-oxacyclohexa-2,3,5-triene (3delta(2)-pyran), their benzo derivatives, and cyclohexa-1,2-diene. An experimental approach to 3delta(2)-pyran.

    Science.gov (United States)

    Engels, Bernd; Schöneboom, Jan C; Münster, Arno F; Groetsch, Stefan; Christl, Manfred

    2002-01-16

    The six-membered cyclic allenes given in the title have been studied theoretically by means of an MR-CI approach. For all compounds, the allene structures were found to be the ground states in the gas phase. In the cases of cyclohexa-1,2-diene (1), the isobenzene 2, and the isonaphthalene 7, the most stable structures having a planar allene moiety are the diradicals 1b, 2b, and 7b, representing the transition states for the racemization of 1a, 2a, and 7a and being less stable than the latter by 14.1, 8.9, and 11.2 kcal/mol, respectively. At variance with this order, the 3delta(2)-pyran 4 and the chromene 5 have the zwitterions 4c and 5c as the most stable planar structures, which lie only 1.0 and 5.4 kcal/mol above 4a and 5a, respectively. According to the simulation of the solvent effect, 4c even becomes the ground state of 4 in THF solution. The frontier orbitals of the respective states of 2 and 4 suggest different rates and sites for the reaction with nucleophiles. For the first time, the pyran 4 has been generated and trapped. As a precursor for 4, 3-bromo-4H-pyran (9) was chosen, the synthesis of which was achieved on two routes from 4H-pyran. The treatment of 9 with potassium tert-butoxide (KOt-Bu)/18-crown-6 gave 4-tert-butoxy-4H-pyran as the only discernible product, whether styrene or furan was present, indicating the interception of 4 by KOt-Bu. Finally, the disagreement between the experiment and the theory concerning the heat of formation and the electronic nature of the isobenzene 2 is resolved by demonstrating that the experimental data can provide only an upper limit of the DeltaH(f) degrees value.

  17. Organobase-catalyzed three-component reactions for the synthesis of 4H-2-aminopyrans, condensed pyrans and polysubstituted benzenes

    Directory of Open Access Journals (Sweden)

    Moustafa Sherief Moustafa

    2014-01-01

    Full Text Available Novel routes for the preparation of 2-amino-4H-pyran-3-carbonitrile 9, amino-arylbenzoic acid ester derivatives 13a,b, 2-aminotetrahydro-4H-chromene-3-carbonitrile 18, 3-amino-4-cyanotetrahydronaphthalene-2-carboxylic acid ester 26 and 4-amino-3,5-dicyanophthalic acid ester derivatives 37a–c were developed. The synthetic methods utilize one-pot reactions of acetylene carboxylic acid esters, α,β-unsaturated nitriles and/or active methylenenitriles in the presence of L-proline or DABCO. Plausible mechanisms are suggested for the formation of the products. Finally, these compounds were used for the efficient synthesis of 6-amino-5-cyanonicotinic acid ester derivatives 31a,b, ethyl 4-amino-5H-pyrano[2,3-d]pyrimidine-6-carboxylates 33a,b, 4-amino-6H-pyrrolo[3,4-g]quinazoline-9-carbonitrile 39, and 1,7-diamino-6-(N'-hydroxycarbamimidoyl-3-oxo-5-phenyl-3H-isoindole-4-carboxylate (40.

  18. Characterization and hypoglycemic activity of a β-pyran polysaccharides from bamboo shoot (Leleba oldhami Nakal) shells.

    Science.gov (United States)

    Zheng, Yafeng; Zhang, Shuai; Wang, Qi; Lu, Xu; Lin, Liangmei; Tian, Yuting; Xiao, Jianbo; Zheng, Baodong

    2016-06-25

    The bamboo shoot (Leleba oldhami Nakal) shell is a by-product during bamboo shoot processing. It is a cheap and available resource for dietary polysaccharides. Herein, a novel polysaccharide BSSP2a was isolated and characterized from the bamboo shoot shell polysaccharides, and it was identified as a homogeneous highly-branched beta type pyran polysaccharide with a molecular weight of 1.63×10(4)kDa, which consisted of arabinose, xylose, mannose, glucose and galactose at a molar ratio of 20.4:4.9:1:3.4:20.6. The crude polysaccharides (BSSP) from the bamboo shoots shell showed hypoglycemic activity on the high fat diet and streptozotocin induced diabetic mice in a dose-dependent manner. The administration of high dose BSSP (400mg/kg) improved body weight loss and serum insulin loss, and significantly decreased the blood glucose level, serum triglycerides as well as total cholesterol levels by 48.7%, 34.8% and 26.5%, respectively. The results highlight the potential of the bamboo shoot shell polysaccharides as a natural anti-diabetic agent.

  19. An Efficient, Simple and Green Zn(Phen2Cl2 Complex Catalyzed Synthesis of 4-H-Benzo[b]pyrans in Water at Ambient Temperature

    Directory of Open Access Journals (Sweden)

    E. Mosaddegh

    2011-01-01

    Full Text Available An efficient method for the synthesis of 4-H-benzo[b]pyrans has been developed by the use of Zn(Phen2Cl2(2 mol% as an ecofriendly catalyst. The mixture of an appropriate aldehyde, malononitrile and dimedone in the presence of the Zn(Phen2Cl2 as an inorganic catalyst in water at room temperature resulted excellent yields of the corresponding products in 5 min. Very short experimental time of the reaction, excellent yields, use of water as a green solvent, simple work-up and uses no extra catalyst and purification are the advantages of this method.

  20. Ethyl 6-(4-chlorophenyl-2,2-dimethyl-4-oxo-3,4-dihydro-2H-pyran-5-carboxylate

    Directory of Open Access Journals (Sweden)

    N. Sharmila

    2017-01-01

    Full Text Available The title compound, C16H17ClO4, is a derivative of 3,4-dihydro-2H-pyran-4-one in which the root moiety forms a dihedral angle of 49.36 (5° with the pendent chlorobenzene ring. The crystal structure features weak methyl-C—H...O(ring carbonyl contacts, leading to an R22(12 ring motif, and benzene-C—H...O(ester interactions, leading to a supramolecular chain along the b axis, to form a three-dimensional network.

  1. INTERACTION OF LASER RADIATION WITH MATTER. LASER PLASMA: Limitation of high-power optical radiation by organic molecules: I. Substituted pyranes and cyanine dyes

    Science.gov (United States)

    Kopylova, T. N.; Svetlichnyi, Valerii A.; Mayer, G. V.; Reznichenko, A. V.; Podgaetskii, Vitalii M.; Ponomareva, O. V.; Samsonova, L. G.; Filinov, D. N.; Pomogaev, V. A.; Tel'minov, E. N.; Lapin, I. N.; Svetlichnaya, N. N.; Sinchenko, E. I.

    2003-11-01

    Photophysical processes proceeding in polyatomic organic molecules (pyran derivatives and cyanines) excited by high-power laser radiation at 532 nm are studied. Some properties of their changes depending on the structure, solvent, and excitation conditions are determined. The effect of limitation of high-power exciting radiation by the organic molecules is found. The maximum limitation (Kmax = 15.0 at the initial transmission equal to 70%) was observed for the cyanine derivative and is comparable to this effect for fullerenes C60, which are widely used as radiation limiters.

  2. Ethyl (E-2-(2,7-dimethyl-5-oxo-4H,5H-pyrano[4,3-b]pyran-4-ylideneacetate

    Directory of Open Access Journals (Sweden)

    Oulemda Bassou

    2017-02-01

    Full Text Available In the title compound, C14H14O5, the two heterocyclic rings are coplanar (r.m.s. deviation = 0.008 Å, with the largest deviation from the mean plane being 0.012 (1 Å. The mean plane through the acetate group is inclined slightly with respect to the oxopyrano[4,3-b]pyran-4-yl system, as indicated by the dihedral angle of 1.70 (7° between them. Two intramolecular hydrogen bonds, completing S(6 ring motifs, are observed in the molecule. In the crystal, molecules are linked by weak C—H...O hydrogen bonds involving the same acceptor atom, forming chains propagating along the c-axis direction and enclosing R21(6 ring motifs. The chains are linked via offset π–π interactions [intercentroid distance = 3.622 (1 Å], involving inversion-related oxopyrano[4,3-b]pyran-4-yl ring systems, forming slabs parallel to the bc plane.

  3. Spin-orbit Coupling and Intersystem Crossing in 4H-Pyran-4-thione: CASSCF//TD-B3LYP Study

    Institute of Scientific and Technical Information of China (English)

    L(U), Ling-Ling; LIU, Xin-Wen; YUAN, Kun; WANG, Yong-Cheng; WANG, Han-Qing

    2007-01-01

    The intersystem crossing channels of gaseous 4H-pyran-4-thione were investigated using the CASSCF//TD-B3LYP methods and group theory. Using the effective one-electron spin-orbit Hamiltonian, the strengths of spin-orbit coupling were estimated, which plays an essential role in the spin transitions between different spin states. Calculated results show that phosphorescence and non-radiative decay via intersystem crossing to the S0 state are concurrent processes occurring at the T1 state. A rapid depletion of the S1 state via intersystem crossing to the T1 state can be mediated by the T2 state, if spin relaxation is fast within the triplet levels. Our calculated results are in close agreement with experimental observations.

  4. Synthesis, characterization, and crystal structure of 2-amino-7-methyl-5-oxo-4-phenyl-4,5-dihydropyrano[3,2-c] pyran-3-carbonitrile

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, S. [University of Jammu, X-ray Crystallography Laboratory, Post-Graduate Department of Physics and Electronics (India); Banerjee, B.; Brahmachari, G. [Visva-Bharati (a Central University), Laboratory of Natural Products & Organic Synthesis, Department of Chemistry (India); Kant, Rajni; Gupta, V. K., E-mail: vivek-gupta2k2@hotmail.com [University of Jammu, X-ray Crystallography Laboratory, Post-Graduate Department of Physics and Electronics (India)

    2015-12-15

    2-Amino-7-methyl-5-oxo-4-phenyl-4,5-dihydropyrano[3,2-c] pyran-3-carbonitrile, C{sub 16}H{sub 12}N{sub 2}O{sub 3} is synthesized via one-pot multi-component reaction at room temperature using commercially available urea as inexpensive and environmentally benign organo-catalyst. Its structure is determined by single-crystal X-ray diffraction technique The crystals are monoclinic, a = 10.7357(12), b = 8.7774(8), c = 15.0759(16) Å, β = 103.575(11)°, Z = 4, sp. gr. P2{sub 1}/n, R = 0.0551 for 1696 observed reflections. The crystal structure is stabilized by N–H···N, C–H···O, and C–H···π interactions.

  5. Type II Anion Relay Chemistry: Exploiting Bifunctional Weinreb Amide Linchpins for the One-Pot Synthesis of Differentiated 1,3-Diketones, Pyrans, and Spiroketals.

    Science.gov (United States)

    Farrell, Mark; Melillo, Bruno; Smith, Amos B

    2016-01-04

    The design, synthesis, and validation of new highly effective bifunctional linchpins for type II anion relay chemistry (ARC) has been achieved. The mechanistically novel negative-charge migration that comprises the Brook rearrangement is now initiated by a stabilized tetrahedral intermediate, which is generated by nucleophilic addition to a Weinreb amide, rather than by a simple oxyanion that is generated from an epoxide. As a result, the linchpin preserves the carbonyl functionality in the ARC adducts, thus permitting access to functionally complex systems in a single flask without the need for further chemical manipulations. This tactic was validated with the one-pot preparation of monoprotected 1,3-diketones as well as pyran and spiroketal scaffolds, depending on the choice of nucleophile, electrophile, and work-up conditions.

  6. Direct alkenylation of indolin-2-ones by 6-aryl-4-methylthio-2H-pyran-2-one-3-carbonitriles: a novel approach

    Directory of Open Access Journals (Sweden)

    Sandeep Kumar

    2013-04-01

    Full Text Available A direct one-pot base-induced alkenylation of indolin-2-ones has been developed by using 6-aryl-4-methylthio-2H-pyran-2-one-3-carbonitriles. Different bases such as MeONa, NaH and t-BuONa have been used to optimize the reaction conditions to obtain the desired product. NaH in THF was found to be the most suitable for the alkenylation of indolin-2-ones. Reaction in the presence of other bases led to the formation of 1-aryl-3-methoxy/methylthio-5H-dibenzo[d,f][1,3]diazepin-6(7H-ones. Quantum chemical calculations have been performed to explain the nature of the weak noncovalent interactions operating in the supramolecular architectures of alkenylated indoline-2-ones and to explain the relative stability of one of the tautomers with respect to the others.

  7. Crystal structure of 2-amino-3-cyano-4-(4-methoxyphenyl-4H-1-benzothieno[3,2-b]pyran

    Directory of Open Access Journals (Sweden)

    Mohamed Bakhouch

    2015-12-01

    Full Text Available The three fused five- and six-membered rings in the title compound, C19H14N2O2S, are virtually coplanar, with the maximum deviation from the mean plane being 0.060 (1 Å. This benzothieno[3,2-b]pyran ring system is nearly perpendicular to the plane of the 4-methoxyphenyl ring, forming a dihedral angle of 83.65 (5°. In the crystal, molecules are linked by pairs of N—H...N hydrogen bonds into inversion dimers. The dimeric units are further connected by an N—H...O hydrogen bond into a tape running along the b axis. The tapes are linked together by C—H...N and π–π interactions [centroid–centroid distance = 3.7743 (8 Å], forming a three-dimensional network.

  8. Synthesis and in vitro antimicrobial screening of new pyrano[4,3-b]pyrane derivatives of 1H-pyrazole

    Institute of Scientific and Technical Information of China (English)

    Chetan B. Sangani; Divyesh C. Mungra; Manish P. Patel; Ranjan G. Patel

    2012-01-01

    A new series of pyrano[4,3-b]pyrane 4a-(I) bearing 1H-pyrazole has been synthesized by one pot base catalyzed cyclocondensation reaction of 1H-pyrazole-4-carbaldehyde 1a-(1),malononitrile 2 and 4-hydroxy-6-methylpyrone 3.All the synthesized compounds were screened against six bacterial pathogens,namely B.subtilis,C.tetani,S.pneumoniae,S.typhi,V.cholerae,E.coli and antifungal activity against,two fungal pathogens,A.fumigatus and C.albicans using broth microdilution MIC method.Some of the compounds are found to be equipotent or more potent than that of commercial drugs,against most of employed strains.

  9. CaCl(2) as a bifunctional reusable catalyst: diversity-oriented synthesis of 4H-pyran library under ultrasonic irradiation.

    Science.gov (United States)

    Safaei, Hamid Reza; Shekouhy, Mohsen; Shirinfeshan, Athar; Rahmanpur, Sudabeh

    2012-11-01

    CaCl(2) is applied as an efficient reusable and eco-friendly bifunctional catalyst for the one-pot three-component synthesis of 4H-pyrans under ultrasonic irradiation. A broad range of substrates including the aromatic and heteroaromatic aldehydes, indoline-2,3-dione (isatin) derivatives, acenaphthylene-1,2-dione (acenaphthenequinone) and 2, 2-dihydroxy-2H-indene-1,3-dione (ninhydrin) were condensed with carbonyl compounds possessing a reactive α-methylene group and alkylmalonates. All reactions are completed in short times, and the products are obtained in good to excellent yields. The catalyst could be recycled and reused several times without any loss of efficiency.

  10. Ceria-Vanadia/Silica-Catalyzed Cascade for C-C and C-O Bond Activation: Green One-Pot Synthesis of 2-Amino-3-cyano-4H-pyrans.

    Science.gov (United States)

    Maddila, Surya Narayana; Maddila, Suresh; van Zyl, Werner E; Jonnalagadda, Sreekantha B

    2016-02-01

    We designed a ceria-vanadia/silica (Ce-V/SiO2) heterogeneous catalyst and used it for the green and efficient synthesis of 2-amino-3-cyano-4H-pyran derivatives. The green reaction was a multicomponent one-pot condensation of 5,5-dimethylcyclohexane-1,3-dione, aromatic aldehyde, and malononitrile in an eco-compatible solvent (ethanol). The catalyst was synthesized and fully characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and Brunauer-Emmett-Teller (BET) surface area analysis. The reported procedure offers a number of advantages including decreased reaction times, mild conditions, high yields, operational simplicity, and environmentally benign and simple work-up procedures. Furthermore, the catalyst is economical, fully recyclable, and reusable for over five runs while preserving its high activity. The synthesized 2-amino-3-cyano-4H-pyran products can later be used for pharmaceutical purposes.

  11. Preparation and characterization of nano-CaO based on eggshell waste:Novel and green catalytic approach to highly efficient synthesis of pyrano[4,3-b]pyrans

    Institute of Scientific and Technical Information of China (English)

    Elaheh Mosaddegh; Asadollah Hassankhani

    2014-01-01

    Nano-CaO was prepared by calcination of ball-milled chicken eggshell waste. This novel, bioactive, heterogeneous catalyst, which had high catalytic activity and reusability, was used in the green synthesis of pyrano[4,3-b]pyrans via condensation of various aromatic aldehydes, malononitrile, and 4-hydroxy-6-methyl-2H-pyran-2-one at 120 °C under solvent-free conditions. The reaction proceeded to completion within 5-45 min in 93%-98% yield. The nano-CaO was fully characterized by scanning electron microscopy, X-ray powder diffraction, infrared spectroscopy, X-ray fluores-cence spectroscopy, and thermal gravimetric, surface area, and elemental analyses.

  12. A New and Facile Protocol for the Synthesis of Dithiocarbamate-linked 3,4-Dihydro-2H-pyran Using N-Halo Catalysts Under Mild Conditions Reaction

    Energy Technology Data Exchange (ETDEWEB)

    Ramin, Ghorbanivaghei; Amiri, Mostafa [Bu-Ali-Sina Univ., Hamedan (Iran, Islamic Republic of); Veisi, Hojat [Payame Noor Univ., Tehran (Iran, Islamic Republic of)

    2012-12-15

    A new and facile protocol for the synthesis of dithiocarabamate in EtOH/H{sub 2}O is described. Reaction of aromatic and aliphatic amines with CS{sub 2} and 3,4-dihydro-2H-pyran in the presence of N,N,N',N'-tetrabromo-benzene-1,3-disulfonamide [TBBDA] and poly(N-bromo-N-ethylbenzene-1,3-disulfonamide) [PBBS] gives the corresponding dithiocarbamates in good to high yields.

  13. Synthesis and antimicrobial evaluation of new pyrano[4,3-b]pyran and Pyrano[3,2-c]chromene derivatives bearing a 2-thiophenoxyquinoline nucleus.

    Science.gov (United States)

    Makawana, Jigar A; Patel, Manish P; Patel, Ranjan G

    2012-04-01

    A new series of pyrano[4,3-b]pyran 4a-i and pyrano[3,2-c]chromene 6a-r derivatives bearing a 2-thiophenoxyquinoline nucleus were synthesized by reaction of 2-(4-(un)-substituted thiophenoxy)quinoline-3-carbaldehydes 2a-i with 6-methyl-4-hydroxypyran-2-one 3 and 4-hydroxy-6-(un)-substituted-2H-chromen-2-one 5a-b respectively and malononitrile at room temperature in the presence of KOH as a basic catalyst. All the compounds were screened against three Gram-positive bacteria (Streptococcus pneumoniae, Bacillus subtilis, Clostridium tetani), three Gram-negative bacteria (Salmonella typhi, Escherichia coli, Vibrio cholerae) and two fungi (Candida albicans, Aspergillus fumigatus) using the broth microdilution MIC (minimum inhibitory concentration) method. Upon antimicrobial screening, it was observed that the majority of the compounds were found to be active against Bacillus subtilis, Clostridium tetani and Candida albicans as compared to standard drugs. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. 5-Bromo-3-(3-hydroxyprop-1-ynyl-2H-pyran-2-one targets prostate cancer cells by down-regulating inflammation-related genes

    Directory of Open Access Journals (Sweden)

    Zhao-Yang Wang

    2016-06-01

    Full Text Available The present study was performed to examine the effect of 5-bromo-3-(3-hydroxyprop-1-ynyl-2H-pyran-2-one (BHP on the rate of cell proliferation and apoptosis induction in the PC3, human prostate carcinoma cell line. The cell viability was assayed by using sulphorhodamine B staining and apoptosis by annexin V and flow cytometry analyses. The results revealed that BHP treatment in PC3 cells caused a significant reduction in the rate of cell proliferation in dose- and time-dependent manner. Compared to the un-treated cells, the formation of HUVEC tubes was markedly inhibited on treatment with BHP at a concentration of 30 µM. Further investigation revealed the expression of HMGB1, IL-6 and IL-8, pro-inflammatory cytokines was also inhibited on treatment with BHP. Therefore, BHP treatment plays an important role in inducing apoptosis in the prostrate cells and can be of therapeutic value for the prostate cancer treatment.

  15. Antimicrobial assay and genetic screening of selected freshwater Cyanobacteria and identification of a biomolecule dihydro-2H-pyran-2-one derivative.

    Science.gov (United States)

    Srivastava, A; Singh, V K; Patnaik, S; Tripathi, J; Singh, P; Nath, G; Asthana, R K

    2017-04-01

    Explorations of freshwater Cyanobacteria as antimicrobial (bacteria, fungi and methicillin-resistant Staphylococcus aureus (MRSA) strains) drug resource using bioassay, NRPS (non-ribosomal polypeptide synthetase) and PKS (polyketide synthase) genes, as well as in silico approach. We have bioassayed the extracts of Phormidium CCC727, Geitlerinema CCC728, Arthrospira CCC729, Leptolyngbya CCC732, Phormidium CCC730, Phormidium CCC731 against six pathogenic bacteria comprising Gram (+ve): S. aureus including seven clinical MRSA and Enterococcus faecalis, Gram (-ve): Escherichia coli, Salmonella Typhimurium, Klebsiella pneumoniae and Shigella boydii along with non-pathogenic Enterobacter aerogenes as well as fungal strains (Cryptococcus neoformans and Candida albicans, C. krusei, C. tropicalis and Aspergillus niger) exhibiting antimicrobial potential. The NRPS and PKS genes of the target strains were also amplified and sequenced. The putative protein structures were predicted using bioinformatics approach. PKS gene expression indicated β keto-acyl synthase as one of the important active domains in the biomolecules related to antitumour and antifungal group. The simultaneous identification of the biomolecule (dihydro-2H-pyran-2-one derivative) was also inferred spectroscopically. Freshwater Cyanobacteria are prolific producers of secondary metabolite(s) that may act as the antimicrobial drug resource in addition to their much explored marine counterpart. © 2016 The Society for Applied Microbiology.

  16. Synthesis and Molecular Structure of Acetic Acid-3,5-diacetoxy-2-acetoxymethyl-6-(4-quinoxalin-2-yl-phenoxy)-tetrahydro-pyran-4-yl-ester

    Institute of Scientific and Technical Information of China (English)

    WEI Hui-Qin; ZENG Run-Sheng; WU Gui-Ping; WANG Bao-An; ZOU Jian-Ping

    2006-01-01

    The title compound, acetic acid-3,5-diacetoxy-2-acetoxymethyl-6-(4-quinoxalin-2-yl-phenoxy)-tetrahydro-pyran-4-yl-ester 8 (C28H28N2O10, Mr = 552.54), has been synthesized and its crystal structure was determined by X-ray diffraction analysis. It crystallizes in monoclinic,space group P21, a = 10.060(8), b = 5.648(4), c=24.11(2)(A), β=91.078(10)O, Z = 2, V =1369.9(19)(A)3, Dc = 1.339 g/cm3,μ(MoKα) = 1.03 cm-1, F(000) = 580.00, T=193.1 K,θmax =25.03, (△/σ)max = 0.0000, Flack = -0.0(24), the final R = 0.0680 and wR= 0.140 (w =1/[0.0016Fo2+ 1.0000σ(Fo2)]/(4Fo2)) for 3126 observed reflections (I>2σ(I)). The pyranoid ring adopts chair conformation in the sugar moiety, and all of the acetyl groups are in the e bond of the pyranoid ring, so the sugar moiety is very stable.

  17. 3-cinnamoyl-4-hydroxy-6-methyl-2H-pyran-2-one (CHP) inhibits human ovarian cell proliferation by inducing apoptosis.

    Science.gov (United States)

    Lan, Qiong-Yu; Liu, Que-Ling; Cai, Jing; Liu, An-Wen

    2015-01-01

    Coumarins induce apoptosis by activating mitochondrial pathway and caspase-3-dependent apoptotic pathway. In the present study, we first time investigated the effect of 3-cinnamoyl-4-hydroxy-6-methyl-2H-pyran-2-one (CHP) on induction of apoptosis in human ovarian carcinoma cells. The data from MTT assay revealed a significant inhibitory effect on cell viability at 30 (87%) and 50 μM (74%) concentration of CHP in OVCAR-3 and OVCAR-420 cells, respectively after 72 h. Apoptosis analysis using annexin V/PI double staining followed by flow cytometry showed 59 and 52% binding to annexin V-FITC in OVCAR-3 and OVCAR-420 cells respectively. propidium iodide (PI) staining and flow cytometry examination indicated a significant increase in percentage of cells in G2/M phase after treatment with CHP compared to DMSO control group. Reactive oxygen species (ROS) assay kit showed increase in levels of ROS. We used rhodamine-123 (Rh-123) staining and flow cytometry assay to determine changes in mitochondrial membrane potential (ΛΨm). The results revealed that CHP significantly decreased MMP to 85.65 ± 1.2443% & 49.78 ± 1.6554% at 10 and 30 μM respectively in OVCAR-3 compared to 95.97 ± 2.1243% in control group. Western blot analysis clearly indicated a significant increase in the expression of Caspase-3, Bax, and release of Cytochrome c and decrease in Bcl-2, CDK1 and Cyclin B1 expression on treatment with CHP. Therefore, CHP may become a potential candidate for the treatment of human ovarian cancers.

  18. The novel trisubstituted pyran derivative D-142 has triple monoamine reuptake inhibitory activity and exerts potent antidepressant-like activity in rodents

    Science.gov (United States)

    Dutta, Aloke K.; Gopishetty, Bhaskar; Gogoi, Sanjib; Ali, Solav; Zhen, Juan; Reith, Maarten

    2011-01-01

    Major depression disorder is a significant health problem with 10-20% of all adults suffering from this disease. The underlying causes of depression are still unclear and 15% of depressed patients are resistant to all known therapies. Monoamine therapies have so far been the most successful approach for treating depression. Triple monoamine reuptake inhibitors have recently been implicated in generation of potent antidepressant activity while possibly exhibiting a low side-effect profile in addition to treating anhedonia. The additional, previously under-appreciated involvement of dopaminergic systems in depression prompted our efforts to develop novel asymmetric trisubstituted and disubstituted pyran derivatives as triple reuptake inhibitors. One of the lead compounds, D-142, exhibited uptake inhibition (Ki) values of 29.3 nM, 14.7 nM and 37.4 nM for norepinephrine, serotonin and dopamine transporters, respectively. Its affinity for serotonin transporter was comparable to fluoxetine , a well known SSRI. In the rat forced swimming test, compound D-142 exhibited potent antidepressant activity in the dose range tested (2.5, 5 and 10 mg/kg) and was far more efficacious than the reference compound imipramine. In the mouse tail suspension test, compound D-142 reduced immobility in a dose (2.5, 5 and 10 mg/kg) dependent manner, indicating a potent antidepressant effect. In locomotor activity tests, compound D-142 did not exhibit any stimulation in the same dose ranges. In the extended CNS receptors screening assay this molecule exhibited little or no non-specific interaction in the CNS, indicating high specificity for monoamine transporters. These results advance D-142 as a potential potent antidepressant. PMID:21963455

  19. Synthesis and characterization of ES/Cu(OH){sub 2} nanocomposite: A novel and high effective catalyst in the green synthesis of pyrano[4,3-b]pyrans

    Energy Technology Data Exchange (ETDEWEB)

    Mosaddegh, Elaheh, E-mail: emosaddegh@gmail.com [Department of New Materials, Institute of Science and High Technology and Environmental Sciences, Graduate University of Advanced Technology, PO Box 76315-117, Kerman (Iran, Islamic Republic of); Hassankhani, Asadollah, E-mail: ahassankhani@gmail.com [Department of New Materials, Institute of Science and High Technology and Environmental Sciences, Graduate University of Advanced Technology, PO Box 76315-117, Kerman (Iran, Islamic Republic of); Karimi-Maleh, Hassan, E-mail: h.karimi.maleh@gmail.com [Department of Chemistry, Graduate University of Advanced Technology, PO Box 76315-117, Kerman (Iran, Islamic Republic of)

    2015-01-01

    The eggshell (ES) supported Cu(OH){sub 2} nanoribbons containing 8 wt.% Cu{sup 2+} as a novel and heterogeneous catalyst was synthesized by simply adding an aqueous solution of CuSO{sub 4} on the eggshell support at ambient temperature. The nanocomposite system was characterized by scanning electron microscopy (SEM), transition electron microscopy (TEM), X-ray diffraction (XRD), energy dispersive X-ray (EDX), thermogravimetric analysis (TGA), Fourier transform infrared (FTIR) spectroscopy and BET surface area analysis. Also, electrochemical impedance spectroscopy was used as powerful techniques for an electrical conductivity investigation. The loading of copper on the mesoporous supports provides high catalytic activity for the green synthesis of pyrano[4,3-b]pyrans. The reaction proceeds to completion in 5 min with excellent yields of 93–97%. The suggested strategy for synthesis of pyrano[4,3-b]pyrans is very interesting due to application of a green and low cost composite as a heterogeneous catalyst and its simplicity in preparation, short reaction time, high yields without further purification and high reusability without any loss of catalytic activity. - Highlights: • Synthesis and full characterization of ES/Cu(OH){sub 2} nanocomposite • ES/Cu(OH){sub 2} characterization with XRD, TGA, FTIR spectra, SEM, TEM and BET • Green and rapid synthesis of pyrano[4,3-b]pyrans in the presence of eggshell supported Cu(OH){sub 2} nanoribbons • High catalytic activity and reusability of nanocomposite even after three cycles • Investigation of electrical conductivity of nanocatalyst.

  20. A Facile Synthesis of New 2-Amino-4H-pyran-3-carbonitriles by a One-Pot Reaction of ,′-Bis(arylidene Cycloalkanones and Malononitrile in the Presence of KCO

    Directory of Open Access Journals (Sweden)

    Zahed Karimi-Jaberi

    2012-01-01

    Full Text Available A rapid and environmentally friendly method is developed for the synthesis of a series of new substituted 2-amino-4H-pyran-3-carbonitriles through a one-pot condensation of malononitrile and ,-bis(arylidene cycloalkanones in ethanol by using K2CO3 as a catalyst. Short experimental reaction times, excellent yields, no need to use cumbersome apparatus for purification of the products, and inexpensiveness and commercially availability of the catalyst are the advantages of this method.

  1. Ultrasound promoted one-pot synthesis of 2-amino-4,8-dihydropyrano[3,2-b]pyran-3-carbonitrile scaffolds in aqueous media: a complementary 'green chemistry' tool to organic synthesis.

    Science.gov (United States)

    Banitaba, Sayed Hossein; Safari, Javad; Khalili, Shiva Dehghan

    2013-01-01

    A green and simple approach to assembling of 2-amino-4,8-dihydropyrano[3,2-b]pyran-3-carbonitrile scaffolds via three-component reaction of kojic acid, malononitrile, and aromatic aldehydes in aqueous media under ultrasound irradiation is described. The combinatorial synthesis was achieved for this methodology with applying ultrasound irradiation while making use of water as green solvent. In comparison to conventional methods, experimental simplicity, good functional group tolerance, excellent yields, short routine, and selectivity without the need for a transition metal or base catalyst are prominent features of this green procedure.

  2. Crystal structure of 3-{1-[(1-allyl-1H-indazol-6-ylamino]ethylidene}-6-methyl-2H-pyran-2,4(3H-dione

    Directory of Open Access Journals (Sweden)

    Mohamed El Ghozlani

    2014-12-01

    Full Text Available In the title compound, C18H17N3O3, the dihedral angle between the planes of the indazole ring system [maximum deviation = 0.012 (1 Å] and the pyran-2,4-dione ring is 54.03 (6°. An intramolecular N—H...O hydrogen bond closes an S(6 ring. The same H atom also participates in an intermolecular N—H...O hydrogen bond, which generates an inversion dimer. The dimers are linked by weak C—H...O contacts, thereby forming a three-dimensional network.

  3. 5′-Amino-2-oxo-2′,3′-dihydrospiro[indoline-3,7′-thieno[3,2-b]pyran]-6′-carbonitrile 1′,1′-dioxide

    Directory of Open Access Journals (Sweden)

    Shi-De Shen

    2010-09-01

    Full Text Available In the title compound, C15H11N3O4S, the dihedral angle between the mean planes of the dihydroindol-2-one (r.m.s. deviation = 0.015 Å and dihydrothieno[3,2-b]pyran (r.m.s. deviation = 0.011 Å ring systems is 89.53 (3°. The crytal packing is consolidated by intermolecular N—H...O and N—H...N hydrogen bonds, which link the molecules into a two-dimensional network into sheets lying parallel to (100.

  4. Kinetics and Mechanism Investigation on Green and Three –Component One Spot Synthesis of 4H-Tetrahydrobenzo[B]Pyrans using Caffeine as A Facile and Green Catalyst

    Directory of Open Access Journals (Sweden)

    Sayyed Mostafa Habibi-Khorassani

    2016-06-01

    Full Text Available In this article, UV-vis spectroscopy has been used in order to study the reaction kinetics between benzaldehyde 1, malononitrile 2 and dimedone 3 in a mixture of (ethanol / water, 1:2 as solvents in the presence of caffeine as a biodegradable catalyst. A mechanistic insight into the synthesis of 4H-tetrahydrobenzo[b]pyrans included spectral kinetics approaches is revealed. To investigate the influence of various parameters (temperature, solvent, concentration on the degradation efficiency and to discuss whether describing the reaction by the means of the pseudo-first order kinetic model is convenient. The overall order of reaction for the formation of tetrahydrobenzo[b]pyran followed second-order kinetics and the partial orders with respect to 1, 2 and 3 were one, one and zero, respectively. The calculation of kinetic parameters would be an integral part of the report. The results showed that the first step of the reaction mechanism is a rate determining step (RDS and this is confirmed based upon the steady state approximation.

  5. One pot synthesis of pyrano[3,2-c]pyran derivatives in ionic liquid%离子液体中吡喃并[3,2-c]吡喃衍生物的一步合成

    Institute of Scientific and Technical Information of China (English)

    史亚南; 宋飞跃; 丁凯娜; 杜百祥; 李玉玲

    2015-01-01

    A series of pyrano[3,2-c]pyran derivatives were synthesized by the reaction of aromatic aldehydes,mal-ononitrile or cyanoacetate and 4-hydroxy-6-methylpyran-2-one in ionic liquid [bmim+ ][BF-4 ].The structures of the products were characterized by IR and 1 HNMR spectrum.%芳醛、丙二腈或氰乙酸酯和4-羟基-6-甲基吡喃-2-酮在离子液体[bmim+][BF-4]中反应,合成了吡喃并[3,2-c]吡喃衍生物。产物的结构通过红外光谱、核磁共振氢谱进行表征。

  6. The Knoevenagel reaction of cyanoacetylhydrazine with pregnenolone: Synthesis of thiophene, thieno[2,3-d]pyrimidine, 1,2,4-triazole, pyran and pyridine derivatives with anti-inflammatory and anti-ulcer activities.

    Science.gov (United States)

    El-Sayed, Nahed N E; Abdelaziz, Mahmoud A; Wardakhan, Wagnat W; Mohareb, Rafat M

    2016-03-01

    The reaction of pregnenolone with cyanoacetylhydrazine and ammonium acetate at 120°C gave the Knoevenagel condensation product 3. The latter reacted with different reagents to give thiophene, thieno[2,3-d]pyrimidine, 1,2,4-triazole and pyran derivatives. The anti-inflammatory and anti-ulcer evaluations of the newly synthesized products were evaluated and the results showed that compounds 4, 8c, 10, 11, 13c, 15a, 15c, 17a, 17b, 17e, 18a and 18f possessed higher activity compared to the rest of the compounds. In addition to this, the toxicity of these active compounds was studied against shrimp larvae where compounds 15a, 15c and 18a showed non-toxicity against the tested organisms.

  7. Diels-Alder Reactions of 6-Hydroxy-2H-pyran-3(6H)-ones with Cyclopentadiene and Its Application for the Synthesis of New Skeletal Oxa-Cage Compounds

    Institute of Scientific and Technical Information of China (English)

    WU Hsien-Jen; LIU HuiChang; CHENG Lui

    2001-01-01

    @@ The 2(5H)-furanone and 3(6H)-pyranone structures are frequently found in natural products, which have a broad range of biological activities. In addition, furanones and pyranones have served as versatile intermediates in the synthesis of a variety of products. 1 Recently, we envisioned that studies on the synthesis and chemistry of heterocyclic cage compounds can greatly expand the scopes and utilities of cage compounds.2 As part of a program that involves the synthesis, chemistry, and applications of heterocyclic cage compounds, we report here the Diels-Alder reactions of 6-hydroxy2H-pyran-3(6H)-ones 1 and 2 with cyclopentadiene and the application of the cycloadducts for the synthesis of oxa-cage compounds 3-6 with new skeleton. Compound 6 is a potential new chiral amino-alcohol.

  8. 2-Acetyl­amino-1,3,4,6-tetra-O-(tri­methyl­silyl)-2-de­oxy-α-d-gluco­pyran­ose

    Science.gov (United States)

    Cheng, Zhao-Dong; Cui, Yan-Li; Mao, Jian-Wei

    2013-01-01

    The title compound, C20H47NO6Si4, was synthesized by per-O-tri­methyl­silylation of N-acetyl-d-glucosa­mine using chloro­tri­methyl­silane in the presence of hexa­methyl­disiloxane. The tri­methyl­silyl group and acetamido group are located on the same side of the pyran ring, showing an α-configuration glycoside. One of the tri­methyl­silyl groups is disordered over two orientations, with site-occupancy factors of 0.625 (9) and 0.375 (9). In the crystal, N—H⋯O hydrogen bonds link the mol­ecules into supra­molecular chains along the a-axis direction. PMID:23795087

  9. (2-Methyl-4-oxo-4H-pyran-3-olato-κ2O3,O4bis(triphenylphosphane-κPcopper(I–triphenylphosphane–methanol (1/1/1

    Directory of Open Access Journals (Sweden)

    Fabian M. A. Muller

    2011-05-01

    Full Text Available In the title compound, [Cu(C6H5O3(C18H15P2]·C18H15P·CH3OH, the pyran-4-one ring is appromimately planar (r.m.s deviation = 0.0138 Å, with the CuI atom 0.451 (5 Å out of the plane. The CuI atom has a distorted tetrahedral coordination. The O—Cu—O angle is 80.07 (8° and the P—Cu—P angle is 123.49 (3°. The crystal packing is stablized by intramolecular C—H...O interactions and intermolecular C—H...O and O—H...O interactions.

  10. Estudio Cinético de la Descomposición Térmica de Tres Derivados del Pirano (C5H6O Kinetic Study of the Thermal Decomposition of Three Derived from the Pyran (C5H6O

    Directory of Open Access Journals (Sweden)

    Jennifer J Lafont

    2009-01-01

    Full Text Available El artículo presenta el estudio cinético de descomposición térmica de tres compuestos derivados del pirano que no han sido reportados en la literatura. Estos compuestos son ampliamente utilizados en farmacología y en la obtención de importantes productos a nivel tecnológico e industrial. Los compuestos 2,6-dietoxitetrahidro-2H-pirano; 2-etoxi-6-propoxitetrahidro-2H-pirano y 2-etoxi-6-butoxi-tetrahidro-2H-pirano se escogieron variando el sustituyente ubicado en la posición 6 del núcleo. Cada experimento cinético fue realizado a cinco temperaturas con intervalos de 10 grados en un rango entre 333 a 373 K, utilizando un sistema de reacción a microescala. Se obtuvieron los productos 2-etoxi-6-hidroxi-tetrahidro-2H-pirano y etileno, propeno, o buteno para cada caso, fueron identificados mediante la técnica de cromatografía de gases acoplada a masas. Las reacciones resultaron ser unimoleculares homogéneas y de primer orden. Teniendo en cuenta los parámetros cinéticos y termodinámicos obtenidos, se puede decir que la reacción es compatible con un estado de transición cíclico de seis miembros, concertado y semipolar.The article presents a kinetic study of the thermal decomposition of three compounds derived from pyran that have not been reported in the literature. These compounds are widely used in pharmacology to obtain important products of technological and industrial interest. The compound (2,6-dietoxitetrahydro-2H-pyran; 2-etoxi-6-propoxytetrahydro-2H-pyran and 2-etoxi-6-butoxytetra-hydro-2H-pyran were chosen by varying the substituent located in the 6 position of the nucleus. Each experiment was done at five temperature with intervals of 10 degrees in a range between 333 and 373 K, using a microscale reaction system. The products obtained, 2-etoxy-6-hydroxy-tetrahydro-2H-pyran and ethylene, propene, or butene for each case, were identified using gas chromatography connected to masses. The reactions turned out to be unimolecular

  11. Identification of a novel glucosylsulfate conjugate as a metabolite of 3,4-dihydro-2,2-dimethyl-2H-naphtho[1,2-b]pyran-5,6-dione (ARQ 501, beta-lapachone) in mammals.

    Science.gov (United States)

    Savage, Ronald E; Tyler, Andrew N; Miao, Xiu-Sheng; Chan, Thomas C K

    2008-04-01

    3,4-Dihydro-2,2-dimethyl-2H-naphtho[1,2-b]pyran-5,6-dione (ARQ 501) is a fully synthetic version of the natural product beta-lapachone, which has been isolated from the lapacho tree (Tabebuia impetiginosa or Tabebuia avellanedae) and has demonstrated promising anticancer activity. ARQ 501 formulated with hydroxypropyl-beta-cyclodextrin has successfully completed phase I clinical trials and is currently in several phase II human clinical trials for the treatment of pancreatic cancer, head and neck cancer, and leiomyosarcoma. The metabolites of ARQ 501 were investigated by low-resolution and high-resolution mass spectrometry in plasma from (nu/nu) mice, rats, and humans treated with the compound. The data for one of the metabolites identified are consistent with conjugation of ARQ 501 with a glucosylsulfate moiety (m/z 241; fragment ion). Although other glucosylsulfate conjugates have been identified as metabolites of pesticides in cotton plants and in crustaceans as phase II metabolites of pyrenes, none have been previously identified in mammals. Data reported here identify a novel metabolic pathway for humans.

  12. Synthesis,Crystal Structure and Anti-tumor Activity of Ethyl 3-(4-methoxyphenyl)-4-oxo-3,3a,4,6-tetrahydro-1H-furo[3,4-c]pyran-3a-carboxylate

    Institute of Scientific and Technical Information of China (English)

    ZHONG Han-Yu; WANG Tian-Tian; ZHANG Yi-Kai; CHEN Huan; LV Zhi-Liang; ZHANG Ming-Feng; GENG Dong-Ping; NIU Chun-Juan; LI Ke

    2011-01-01

    The title compound(ethyl 3-(4-methoxyphenyl)-4-oxo-3,3a,4,6-tetrahydro-1H-furo[3,4-c]pyran-3a-carboxylate) has been synthesized,and its crystal structure was characterized by X-ray single-crystal diffraction.The crystal belongs to monoclinic,space group P21/n,with a = 10.124(4),b = 11.754(4),c = 13.792(5) ,β = 111.533(3)o,V = 1526.6(10) 3,Z = 4,C17H19O6,Mr = 319.32,Dc = 1.389 g/cm3,F(000) = 676,λ(MoKα) = 0.71073 ,μ = 0.105 mm-1,R = 0.0660 and wR = 0.2027 for 2993 observed reflections(I 2σ(I)).The compound shows potent anti-tumor activity in vitro.

  13. Synthesis and Structural Studies of Transition Metal Complexes with Bidentate Schiff Base Derived from 3-Acetyl-6-methyl-(2H-pyran-2,4(3H-dione

    Directory of Open Access Journals (Sweden)

    Praveen S. Mane

    2011-01-01

    Full Text Available The solid complexes of Cu(II, Ni(II, Co(II, Mn(II and Fe(III with Schiff base ligands derived from heterocyclic compounds 3-acetyl-6-methyl-(2H-pyran-2,4(3H-dione (Dehydroacetic acid and o-chloroaniline were synthesized and characterized by elemental analysis, conductance, magnetic, thermal, UV-Vis and 1H-NMR spectroscopy. The ligand field parameters have been evaluated for Cu(II, Ni(II, Co(II, Mn(II and Fe(III complexes which suggest an octahedral geometry for each of them. The magnetic moment and spectral data suggest the dimeric nature of Mn(II complexes with octahedral geometry. The fungicidal activities of the ligands and their metal complexes have been screened in vitro against Aspergillus niger and the percentage inhibition of the metal complexes is found to be increased considerably then that of their corresponding ligands and the order is Cu>Ni>Fe>Mn>Co.

  14. Continuous irradiation and flash-photolysis studies of new[3H]naphtho[2,1-b]pyrans linked by covalent bonds to oligothiophene units. Effect of thiophene substituents on the photochromism.

    Science.gov (United States)

    Frigoli, Michel; Pimienta, Véronique; Moustrou, Corinne; Samat, André; Guglielmetti, Robert; Aubard, Jean; Maurel, François; Micheau, Jean-Claude

    2003-08-01

    The influence of oligothiophene substituents on five new [3H]naphtho[2,1-b]pyrans has been investigated using flash photolysis and continuous irradiation techniques. Photochromic properties strongly depend on the number and position of the thienyl units. Thienyl substitution increases the UV/visible absorbance of the lower energy transition of both the naphthopyran and merocyanine isomers. The rate constants of the thermal fading processes also increase with the number of thiophenic entities. Although several minor photoisomers, whose relative amounts depend on the irradiation conditions could be involved, it has been assumed that under continuous monochromatic irradiation, the evolution of the photochromic reaction can be described by the formation of only one photoisomer. Under these conditions, quantum yields of photocolouration and molar absorption coefficients of the non-isolable photomerocyanine isomer were evaluated by photokinetic analysis. Flash-photolytic colourability can be interpreted using continuous irradiation parameters. A linear correlation has been established between experimental and calculated colourability. This result shows that similar photochromic reactions leading to similar photoisomers are triggered either by polychromatic flash photolysis or by continuous monochromatic irradiation.

  15. Synthesis and Crystal Structure of Methyl (7,7-Dimethyl-2-amino-4-(4-chlorophenyl)-5-oxo-5,6,7,8-tetrahydro-4H-benzo-[b]-pyran-3-yl) Carboxylate

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The title compound methyl (7,7-dimethyl-2-amino-4-(4-chlorophenyl)-5-oxo- 5,6,7,8-tetrahydro-4H-benzo-[b]-pyran-3-yl) carboxylate (C19H20ClNO4, Mr = 361.81) was synthesized and crystallized. The crystal belongs to triclinic, space group P ī with a = 8.519(2), b = 10.346(2), c = 11.481(3) ?, ( = 108.16(1), ( = 107.78(2), ( = 91.83(2)(, Z = 2, V = 906.5(3) ?3, Dc = 1.326 g/cm3, ((MoK() = 0.234 mm-1, F(000) = 380, R = 0.0467 and wR = 0.1270 for 3142 observed reflections (I ( 2((I)). X-ray analysis reveals that the C(7), C(8), C(9), O(1), C(10) and C(11) atoms form a six-membered ring which adopts a boat conformation. In the ring, the distances of C(8)-C(9) and C(10)-C(11) are 1.332(3) and 1.357(3) (A), respectively, which indicates that they are C=C double bonds. Another six-membered ring (C(8)-C(9)-C(15)-C(14)-C(13)-C(12)) adopts the half-chair conformation. In addition, there are intermolecular hydrogen bonds in the crystal structure.

  16. Synthesis, spectroscopic, crystal structure and DNA binding of Ru(II) complexes with 2-hydroxy-benzoic acid [1-(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)-ethylidene]-hydrazide

    Science.gov (United States)

    Chitrapriya, Nataraj; Sathiya Kamatchi, Thangavel; Zeller, Matthias; Lee, Hyosun; Natarajan, Karuppannan

    2011-10-01

    Reactions of 2-hydroxy-benzoic acid [1-(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)-ethylidene]-hydrazide (H 2L) with [RuHCl(CO)(EPh 3) 3] (E = P or As) were carried out and the new complexes obtained were characterized by elemental analysis, electronic, IR, 1H NMR and 13C NMR spectroscopic techniques and single crystal X-ray diffraction studies. Complex ( 1) crystallizes in the monoclinic space group P2(1)/ c with unit cell dimensions a = 18.6236(17) Å, b = 12.8627(12) Å, c = 21.683(2) Å, α = 90.00, β = 114.626(2), γ = 90.00 V = 4721.8(8) Å, Z = 4. The crystal structure of the complex shows Ru(II) atom is six-coordinated, forming a slightly distorted octahedral geometry with two P atoms in axial positions, and three chelating donor atoms of the tridentate Schiff base ligand and one carbonyl group located in the equatorial plane. The molecular structure is stabilized by intramolecular O—H···N interactions. No intermolecular hydrogen bond was observed. The intramolecular hydrogen bond exists between the oxygen atom from salicylic acid moiety and nitrogen from the same moiety. A variety of solution studies were carried out for the determination of DNA binding mode of the complexes. The results suggest that both complexes bind to Herring sperm DNA via non intercalative mode.

  17. Synthesis of new 2-amino-4H-pyran-3,5-dicarboxylate derivatives using nanocrystalline M{sup II}Zr{sub 4}(PO{sub 4}){sub 6} ceramics as reusable and robust catalysts under microwave irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Safaei-Ghomi, Javad, E-mail: safaei@kashanu.ac.ir [University of Kashan, Department of Organic Chemistry, Faculty of Chemistry (Iran, Islamic Republic of); Javidan, Abdollah [Imam Hossein University, Nano-Research Center (Iran, Islamic Republic of); Ziarati, Abolfazl [University of Tehran, School of Chemistry, College of Science (Iran, Islamic Republic of); Shahbazi-Alavi, Hossein [University of Kashan, Department of Organic Chemistry, Faculty of Chemistry (Iran, Islamic Republic of)

    2015-08-15

    In the present paper, we report the successful synthesis of nanocrystalline M{sup II}Zr{sub 4}(PO{sub 4}){sub 6} ceramics (M: Mn, Ni, Fe, Co). These nano-structures were characterized by X-ray diffraction, scanning electron microscopy, and vibrating sample magnetometer (VSM). Size of nano-structures was in the range of 20–150 nm. Nano-M{sup II}Zr{sub 4}(PO{sub 4}){sub 6} as an efficient and green catalyst has been used for the preparation of 2-amino-4H-pyran-3,5-dicarboxylate derivatives by the three-component condensation reaction of ethyl cyanoacetate, ethyl acetoacetate, and various aromatic aldehydes under microwave irradiation. Extraordinarily, the best results were obtained using MnZr{sub 4}(PO{sub 4}){sub 6} nanocrystallines as an efficient catalyst. This method provides several advantages including easy work-up, excellent yields, short reaction times, using of microwave as green method, recoverability of the catalyst, and little catalyst loading.

  18. Synthesis of 6-Trimethylsilyl-a-pyrone from 2,6-Bis(trimethylsilyl)-pyran via Mild Aerobic Oxidation%氧气氧化2,6-二-(三甲基硅基)吡喃为6-三甲基硅基-α-吡喃酮

    Institute of Scientific and Technical Information of China (English)

    周德军; Matsuya Yuji

    2013-01-01

    In this study,an effective and mild method for the synthesis of 6-trimethylsilyl-α-pyrone was successfully developed. 6-Trimethylsilyl-α-pyrone,a very important intermediate in organic synthesis,was mildly synthesized from pyrane derivative via an aerobic oxidation at room temperature,without any solvents and catalysts. Furthermore,the possible mechanism of the reaction was proposed.%开发出一种合成6-三甲基硅基α-吡喃酮的有效方法.在无溶剂无任何催化剂的氧气气氛中,室温条件下温和地将2,6-二-(三甲基硅基)吡喃通过氧化反应转化成6-三甲基硅基α-吡喃酮,并且给出了该反应可能的机理.

  19. A Study on Spectro-Analytical Aspects, DNA - Interaction, Photo-Cleavage, Radical Scavenging, Cytotoxic Activities, Antibacterial and Docking Properties of 3 - (1 - (6 - methoxybenzo [d] thiazol - 2 - ylimino) ethyl) - 6 - methyl - 3H - pyran - 2, 4 - dione and its Metal Complexes.

    Science.gov (United States)

    Ravi, Mudavath; Chennam, Kishan Prasad; Ushaiah, B; Eslavath, Ravi Kumar; Perugu, Shyam; Ajumeera, Rajanna; Devi, Ch Sarala

    2015-09-01

    The focus of the present work is on the design, synthesis, characterization, DNA-interaction, photo-cleavage, radical scavenging, in-vitro cytotoxicity, antimicrobial, docking and kinetic studies of Cu (II), Cd (II), Ce (IV) and Zr (IV) metal complexes of an imine derivative, 3 - (1 - (6 - methoxybenzo [d] thiazol - 2 - ylimino) ethyl) - 6 - methyl - 3H - pyran - 2, 4 - dione. The investigation of metal ligand interactions for the determination of composition of metal complexes, corresponding kinetic studies and antioxidant activity in solution was carried out by spectrophotometric methods. The synthesized metal complexes were characterized by EDX analysis, Mass, IR, (1)H-NMR, (13)C-NMR and UV-Visible spectra. DNA binding studies of metal complexes with Calf thymus (CT) DNA were carried out at room temperature by employing UV-Vis electron absorption, fluorescence emission and viscosity measurement techniques. The results revealed that these complexes interact with DNA through intercalation. The results of in vitro antibacterial studies showed the enhanced activity of chelating agent in metal chelated form and thus inferring scope for further development of new therapeutic drugs. Cell viability experiments indicated that all complexes showed significant dose dependent cytotoxicity in selected cell lines. The molecular modeling and docking studies were carried out with energy minimized structures of metal complexes to identify the receptor to metal interactions.

  20. Theoretical investigation on the effect of protonation on the absorption and emission spectra of two amine-group-bearing, red "push-pull" emitters, 4-dimethylamino-4'-nitrostilbene and 4-(dicyanomethylene)-2-methyl-6-p-(dimethylamino) styryl-4H-pyran, by DFT and TDDFT calculations.

    Science.gov (United States)

    Petsalakis, I D; Georgiadou, D G; Vasilopoulou, M; Pistolis, G; Dimotikali, D; Argitis, P; Theodorakopoulos, G

    2010-05-06

    A theoretical investigation on the electronic structure of 4-dimethylamino-4'-nitrostilbene (DANS), 4-(dicyanomethylene)-2-methyl-6-p-(dimethylamino) styryl-4H-pyran (DCM), and their protonated forms is presented in an effort to rationalize recent experimental results on the tuning of the emitted color of organic light-emitting diodes through photochemically induced protonation. Density functional theory (DFT) and time-dependent density functional theory (TDDFT) calculations have been carried out on the neutral and protonated forms of DANS and DCM, employing both the B3LYP and the CAM-B3LYP functionals. It was found that the CAM-B3LYP functional leads to better agreement than the B3LYP of the calculated with the experimental absorption lambda(max) for DANS, whereas B3LYP is more appropriate than CAM-B3LYP for DCM. The results of the calculations aid in a rationalization of the observed differences of the spectra of DANS and DCM upon protonation, and in particular those differences that make DANS a more attractive system for absorbance and emission tuning.

  1. 6a-Nitro-6-(2,2,7,7-tetramethyltetrahydro-3aH-bis[1,3]dioxolo[4,5-b:4′,5′-d]pyran-5-yl-6a,6b,7,8,9,11a-hexahydro-6H-spiro[chromeno[3,4-a]pyrrolizine-11,11′-indeno[1,2-b]quinoxaline

    Directory of Open Access Journals (Sweden)

    T. Anuradha

    2014-01-01

    Full Text Available In the title compound, C39H38N4O8, the quinoxaline and indene subunits are essentially planar, with maximum deviations of 0.071 (2 and 0.009 (2 Å, respectively. The indenoquinoxaline system forms a dihedral angle of 72.81 (3° with the chromenopyrrolizine system. The two dioxolane rings, as well as the pyran ring of the chromeno group and the terminal pyrrolizine, each adopt an envelope conformation with O and C as flap atoms. The central pyrrolizine ring adopts a twisted conformation. Intramolecular C—H...O and C—H...N hydrogen bonds occur. The crystal structure exhibits C—H...O hydrogen bonds, and is further stablized by C—H...π interactions, forming a two-dimensional network along the bc plane.

  2. The identification of a novel phosphodiesterase 4 inhibitor, 1-ethyl-5-{5-[(4-methyl-1-piperazinyl)methyl]-1,3,4-oxadiazol-2-yl}-N-(tetrahydro-2H-pyran-4-yl)-1H-pyrazolo[3,4-b]pyridin-4-amine (EPPA-1), with improved therapeutic index using pica feeding in rats as a measure of emetogenicity.

    Science.gov (United States)

    Davis, T Gregg; Peterson, John J; Kou, Jen-Pyng; Capper-Spudich, Elizabeth A; Ball, Doug; Nials, Anthony T; Wiseman, Joanne; Solanke, Yemisi E; Lucas, Fiona S; Williamson, Richard A; Ferrari, Livia; Wren, Paul; Knowles, Richard G; Barnette, Mary S; Podolin, Patricia L

    2009-09-01

    Clinical utility of phosphodiesterase 4 (PDE4) inhibitors as anti-inflammatory agents has, to date, been limited by adverse effects including nausea and emesis, making accurate assessment of emetic versus anti-inflammatory potencies critical to the development of inhibitors with improved therapeutic indices. In the present study we determined the in vitro and in vivo anti-inflammatory potencies of the first-generation PDE4 inhibitor, rolipram, the second-generation inhibitors, roflumilast and cilomilast, and a novel third generation inhibitor, 1-ethyl-5-{5-[(4-methyl-1-piperazinyl)methyl]-1,3,4-oxadiazol-2-yl}-N-(tetrahydro-2H-pyran-4-yl)-1H-pyrazolo[3,4-b]pyridin-4-amine (EPPA-1). The rank-order potency against lipopolysaccharide (LPS)-induced tumor necrosis factor-alpha production by human peripheral blood mononuclear cells was roflumilast (IC(50) = 5 nM) > EPPA-1 (38) > rolipram (269) > cilomilast (389), and against LPS-induced pulmonary neutrophilia in the rat was EPPA-1 (D(50) = 0.042 mg/kg) > roflumilast (0.24) > rolipram (3.34) > cilomilast (4.54). Pica, the consumption of non-nutritive substances in response to gastrointestinal stress, was used as a surrogate measure for emesis, giving a rank-order potency of rolipram (D(50) = 0.495 mg/kg) > roflumilast (1.6) > cilomilast (6.4) > EPPA-1 (24.3). The low and high emetogenic activities of EPPA-1 and rolipram, respectively, detected in the pica model were confirmed in a second surrogate model of emesis, reversal of alpha(2)-adrenoceptor-mediated anesthesia in the mouse. The rank order of therapeutic indices derived in the rat [(pica D(50))/(neutrophilia D(50))] was EPPA-1 (578) > roflumilast (6.4) > cilomilast (1.4) > rolipram (0.15), consistent with the rank order derived in the ferret [(emesis D(50))/(neutrophilia D(50))]. These data validate rat pica feeding as a surrogate for PDE4 inhibitor-induced emesis in higher species, and identify EPPA-1 as a novel PDE4 inhibitor with an improved therapeutic index.

  3. 5-Hydroxy-2-methyl-4H-pyran-4-one

    Directory of Open Access Journals (Sweden)

    Bernhard K. Keppler

    2009-02-01

    Full Text Available The title compound, C6H6O3, is a member of the pyrone family. The molecules are planar (r.m.s. deviation of the asymmetric unit is 0.0248 Å, whereas that of the dimer is 0.0360 Å and they are dimerized due to intermolecular O—H...O hydrogen bonds. The dimers are connected to each other through hydrogen bonds involving the CH3 group and the hydroxy O atom. There are π–π interactions between the centroids of the pyrone rings at a distance of 3.8552 (13 Å. A C—H...π interaction also exists between the carbonyl group and the centroid CgA of the pyrone ring, with O...CgA = 3.65 (1 Å and C...CgA = 4.363 (2 Å.

  4. Regiospecific synthesis of 2-substituted 4-methyl-3,6-dihydro-2h-pyrans

    Energy Technology Data Exchange (ETDEWEB)

    Kazaryan, P.I.; Avakyan, O.V.; Avakyan, S.V.; Gevorkyan, A.A.

    1986-03-01

    The chloroalkylation of 3-halo-2-methyl-1-buten-4-ols was used to synthesize 4,5-dihalo-4-methyl-2-substituted tetrahydropyrans, which were converted regio-specifically to 3,6-dihydropyrans by reaction with magnesium. A similar reaction with zinc dust gave mixtures of 3,6- and 5,6-dihydropyrans.

  5. 6-Hydroxymethyl-4-methoxy-2H-pyran-2-one (Opuntiol

    Directory of Open Access Journals (Sweden)

    Muhammad Athar Abbasi

    2010-01-01

    Full Text Available The title compound, C7H8O4, isolated from Opuntia dillenii Haw (Cactaceae, is almost planar [maximum deviation of 0.027 (2 Å] except for the H atoms of the methylene and methyl groups. The crystal packing is stabilized by C—H...O and O—H...O intermolecular hydrogen bonds, resulting in the formation of a three-dimensional network.

  6. 6-Hydroxy-methyl-4-meth-oxy-2H-pyran-2-one (Opuntiol).

    Science.gov (United States)

    Abbasi, Muhammad Athar; Shahzadi, Tayyaba; Akkurt, Mehmet; Aziz-Ur-Rehman; Riaz, Tauheeda

    2009-12-19

    The title compound, C(7)H(8)O(4), isolated from Opuntia dillenii Haw (Cacta-ceae), is almost planar [maximum deviation of 0.027 (2) Å] except for the H atoms of the methylene and methyl groups. The crystal packing is stabilized by C-H⋯O and O-H⋯O inter-molecular hydrogen bonds, resulting in the formation of a three-dimensional network.

  7. Diethyl 3H-naphtho[2,1-b]pyran-2,3-dicarboxylate

    Directory of Open Access Journals (Sweden)

    Abdullah Mohamed Asiri

    2009-04-01

    Full Text Available The sp3-hybridized methine C atom in the title compound, C19H18O5, lies out of the mean plane of the remaining 13 atoms of the naphthopyran fused-ring system by 0.571 (1 Å, and its H atom occupies a pseudo-equatorial site.

  8. 6-Hydroxy­methyl-4-meth­oxy-2H-pyran-2-one (Opuntiol)

    OpenAIRE

    Muhammad Athar Abbasi; Tayyaba Shahzadi; Mehmet Akkurt; Aziz-ur-Rehman,; Tauheeda Riaz

    2009-01-01

    The title compound, C7H8O4, isolated from Opuntia dillenii Haw (Cactaceae), is almost planar [maximum deviation of 0.027 (2) Å] except for the H atoms of the methylene and methyl groups. The crystal packing is stabilized by C—H...O and O—H...O intermolecular hydrogen bonds, resulting in the formation of a three-dimensional network.

  9. Bis(3-acetyl-6-methyl-2-oxo-2H-pyran-4-olatobis(dimethyl sulfoxidenickel(II

    Directory of Open Access Journals (Sweden)

    Amel Djedouani

    2009-10-01

    Full Text Available In the title compound, [Ni(C8H7O42{(CH32SO}2], the NiII atom is located on a crystallographic centre of symmetry and has a distorted octahedral coordination geometry of type MO6. The bidentate dehydroacetic acid (DHA ligands occupy the equatorial plane of the complex in a trans configuration, and the dimethyl sulfoxide (DMSO ligands are weakly coordinated through their O atoms in the axial positions.

  10. Method to convert biomass to 5-(hydroxymethyl)-furfural (HMF) and furfural using lactones, furans, and pyrans as solvents

    Science.gov (United States)

    Dumesic, James A.; Ribeiro Gallo, Jean Marcel; Alonso, David

    2014-07-08

    Described is a process to produce hydroxymethyl furfural (HMF) from biomass-derived sugars. The process includes the steps of reacting a C5 and/or C6 sugar-containing reactant derived from biomass in a monophasic or biphasic reaction solution comprising water and a co-solvent. The co-solvent can be beta-, gamma-, and/or delta-lactones derived from biomass, tetrahydrofuran (THF) derived from biomass, and/or methyltetrahydrofuran (MTHF) derived from biomass. The reaction takes place in the presence of an acid catalyst and a dehydration catalyst for a time and under conditions such that at least a portion of glucose or fructose present in the reactant is converted to HMF.

  11. Surveying approaches to the formation of carbon-carbon bonds between a pyran and an adjacent ring

    OpenAIRE

    Frein, Jeffrey D.; Rovis, Tomislav

    2006-01-01

    We have examined several methods for the stereoselective formation of carbon-carbon bonds between contiguous rings where a stereogenic center is already present. The approaches investigated were a [1,3] oxygen to carbon rearrangement of cyclic vinyl acetals, an intermolecular enolsilane addition into an in situ generated oxocarbenium ion, an intramolecular conjugate addition of tethered alkoxy enones, and epimerization of several α-pyranyl cycloalkanones. These routes have been found to be co...

  12. PM-3, a benzo-gamma-pyran derivative isolated from propolis, inhibits growth of MCF-7 human breast cancer cells.

    Science.gov (United States)

    Luo, J; Soh, J W; Xing, W Q; Mao, Y; Matsuno, T; Weinstein, I B

    2001-01-01

    Propolis has numerous biologic activities including antibiotic, antifungal, antiviral and anti-inflammatory properties. Several components isolated from propolis have been shown to have anticancer activity. This study demonstrates that the compound PM-3 (3-[2-dimethyl-8-(3-methyl-2-butenyl)benzopyran]-6-propenoic acid) isolated from Brazilian propolis markedly inhibits the growth of MCF-7 human breast cancer cells. This effect was associated with inhibition of cell cycle progression and induction of apoptosis. Treatment of MCF-7 cells with PM-3 arrested cells in the G1 phase and resulted in a decrease in the protein levels of cyclin D1 and cyclin E. PM-3 also inhibited the expression of cyclin D1 at the transcriptional level when examined in cyclin D1 promoter luciferase assays. Induction of apoptosis by PM-3 occurred within 48 hours after treatment of MCF-7 cells. The MCF-7 treated cells also displayed a decrease in the level of the estrogen receptor (ER) protein and inhibition of estrogen response element (ERE) promoter activity. Therefore, PM-3 merits further investigation with respect to breast cancer chemoprevention or therapy.

  13. 6-Hydroxy­methyl-4-meth­oxy-2H-pyran-2-one (Opuntiol)

    Science.gov (United States)

    Abbasi, Muhammad Athar; Shahzadi, Tayyaba; Akkurt, Mehmet; Aziz-ur-Rehman; Riaz, Tauheeda

    2010-01-01

    The title compound, C7H8O4, isolated from Opuntia dillenii Haw (Cacta­ceae), is almost planar [maximum deviation of 0.027 (2) Å] except for the H atoms of the methylene and methyl groups. The crystal packing is stabilized by C—H⋯O and O—H⋯O inter­molecular hydrogen bonds, resulting in the formation of a three-dimensional network. PMID:21580082

  14. Ethyl 2-amino-4-phenyl-4H-1-benzothieno[3,2-b]pyran-3-carboxylate

    Directory of Open Access Journals (Sweden)

    Adil Boughaleb

    2011-08-01

    Full Text Available The title heterocyclic compound, C20H17NO3S, was synthesized by condensation of ethyl cyanoacetate with (Z-2-benzylidenebenzo[b]thiophen-3(2H-one in the presence of a basic catalyst in ethanol. The phenyl and ester groups make dihedral angles of 77.67 (6 and 8.52 (6°, respectively, with the benzothienopyran ring system [maximum r.m.s. deviation = 0.1177 (13 Å]. In the crystal, centrosymmetric dimers are formed through pairs of N—H...O hydrogen bonds between the amine and ester groups. Intermolecular C—H...N hydrogen bonds and C—H...π interactions involving the thiophene ring are also observed.

  15. (5S,6R-6-Bromo-6-methyl-5-phenyl-3,4,5,6-tetrahydro-2H-cyclopenta[b]pyran-7-one

    Directory of Open Access Journals (Sweden)

    Winai Ieawsuwan

    2011-10-01

    Full Text Available The title compound, C15H15BrO2, was synthesized by a Brønsted acid-catalysed domino electrocyclization-halogenation reaction. The five-membered ring is essentially planar (r.m.s. deviation 0.006 Å and forms a dihedral angle of 72.7 (3° with the attached phenyl ring. The six-membered heterocycle adopts a half-chair conformation. The crystal packing is stabilized by a C—H...O contact.

  16. Crystal structure of (E-4-hydroxy-3-{1-[(4-hydroxyphenylimino]ethyl}-6-methyl-2H-pyran-2-one

    Directory of Open Access Journals (Sweden)

    Amel Djedouani

    2015-08-01

    Full Text Available In the title Schiff base, C14H13NO4, which adopts the phenol–imine tautomeric form, the dihedral angle between the planes of the benzene and heterocyclic (r.m.s. deviation = 0.037 Å rings is 53.31 (11°. An intramolecular O—H...N hydrogen bond closes an S(6 ring. In the crystal, molecules are linked by O—H...O hydrogen bonds to generate C(11 chains propagating in the [010] direction. A weak C—H...O link is also observed, leading to the formation of R55(32 rings extending parallel to the (101 plane.

  17. Domino Cyclization of 1,n-Enynes (n = 7, 8, 9) Giving Derivatives of Pyrane, Chromene, Fluorene, Phenanthrene and Dibenzo[7]annulene by Ruthenium Complexes.

    Science.gov (United States)

    Ma, Hao-Wei; Chen, Pei-Min; Lo, Ji-Xian; Lin, Ying-Chih; Huang, Shou-Ling; Chen, Chi-Ren; Chia, Pi-Yeh

    2016-06-03

    Cyclization of the ether enyne 1 catalyzed by [Ru]NCCH3(+) ([Ru] = Cp(PPh3)2Ru) in CHCl3 generates a diastereomeric mixture of the substituted tetrahydropyran 11. Presumably, formation of an allenylidene complex is followed by a cyclization by nucleophilic addition of the olefinic group to Cγ of the ligand giving a boat-like six-membered ring. The diastereoselectivity is controlled by the 1,3-diaxial interaction. The vinylidene complex 7, a precursor of 11, is obtained from 1 and [Ru]Cl. In a mixture of MeOH/CHCl3, the domino cyclization of 1 further affords 14a, a chromene product catalytically. The second cyclization proceeds via nucleophilic addition of the resulting olefinic unit to Cα of 7. But the ether enyne 3 with a cyclopentyl ring on the olefinic unit undergoes only single cyclization due to steric effect. The propargyl alcohol and the two terminal methyl groups on the olefinic unit shape the cyclization. Thus, similar all-carbon 1,n-enynes (n = 7, 8, 9) 4-6 each with an aromatic linker undergo direct domino cyclization catalyzed by [Ru]NCCH3(+), to give derivatives of tricyclic fluorene, phenanthrene and dibenzo[7]annulene, respectively, with no intermediate observed.

  18. Identification of 5,6-dihydro-6-propyl-2H-pyran-2-one as the Major Volatile Constituent in Mesquite (Prosopis) Flour

    Science.gov (United States)

    Mesquite (Prosopis spp.) are woody leguminous plants that belong to the family Leguminosae and grow in arid and semiarid regions of America, Africa and Asia. Prosopis spp. produce indehiscent fruit (pods) that can be milled to yield flour that is sold commercially and is used in pastries and baked ...

  19. Simultaneous quantification of differently glycosylated, acetylated and 2,3-dihydro-2,5-dihydroxy-6-methyl-4h-pyran-4-one-conjugated soyasaponins using reversed-phase high-performance liquid chromatography with evaporative light scattering detection

    NARCIS (Netherlands)

    DeCroos, K.; Vincken, J.P.; Heng, L.; Bakker, R.; Gruppen, H.; Verstraete, W.

    2005-01-01

    A novel method utilizing high-performance liquid chromatography (HPLC) with evaporative light scattering detection (ELSD) and electrospray ionisation mass spectrometry (ESI-MS) was developed for the analysis of soyasaponins, a divers group of triterpenic compounds with one or two sugar side chains,

  20. Methyl 5,7-dihydroxy-2,2,9-trimethyl-6,11-dioxo-6,11-dihydro-2H-anthra[2,3-b]pyran-8-carboxylate

    Directory of Open Access Journals (Sweden)

    Annelise Lobstein

    2008-12-01

    Full Text Available The title compound, C22H18O7, also known as laurentiquinone B, is a new anthraquinone which was isolated from Vismia laurentii, a Cameroonian medicinal plant. The asymmetric unit contains two independent molecules. Each of them contains four fused rings, three of which are coplanar and typical of anthracene, while the heterocyclic rings adopt envelope conformations. Intramolecular O—H...O hydrogen bonds result in the formation of two planar rings, which are also almost coplanar with the adjacent rings. In the crystal structure, intermolecular O—H...O and C—H...O hydrogen bonds link the molecules and a π–π contact is also present [centroid-centroid distance = 3.967 (3 Å].

  1. An improved asymmetric synthetic route to a novel triple uptake inhibitor antidepressant (2S,4R,5R)-2-benzhydryl-5-((4-methoxybenzyl)amino)tetrahydro-2H-pyran-4-ol (D-142)

    Science.gov (United States)

    Gopishetty, Bhaskar; Gogoi, Sanjib; Dutta, Aloke

    2011-01-01

    Triple monoamine reuptake inhibitors have been implicated in the development of a new generation of antidepressants with higher efficacy than the currently existing therapies. In this paper, we have developed an alternative efficient synthetic route for triple monoamine reuptake inhibitor D-142 in 18.5% overall yield in 11 steps starting from diphenylmethane. D-142 was developed by us recently. The key step of the present synthetic strategy is the preferential formation of a bromohydrin from olefin via a cis-bromoinum intermediate, which introduced significant efficiency in the overall synthesis. Furthermore, we have developed an efficient way to recycle the optically active intermediate diol back to the desired chiral epoxide. PMID:21927543

  2. 6-Alkoxymethyl-3-hydroxy-4H-pyranones: potential ligands for cell-labelling with indium

    Energy Technology Data Exchange (ETDEWEB)

    Ellis, B.L. [Royal Infirmary, Manchester (United Kingdom). Dept. of Nuclear Medicine; Sampson, C.B. [Addenbrooke' s Hospital, Cambridge (United Kingdom). Dept. of Nuclear Medicine and Rheumatology; Abeysinghe, R.D.; Porter, J.B. [Univ. Medical School, London (United Kingdom). Dept. of Clinical Haematology,; Hider, R.C. [King' s College London, London (United Kingdom). Dept. of Pharmacy

    1999-11-01

    We have identified ligands for cell labelling with indium-111: 3-hydroxy-6-propoxymethyl-4H-pyran-4-one and 6-butoxymethyl-3-hydroxy-4H-pyran-4-one. The leucocyte labelling efficiencies of {sup 111}In complexes of these ligands were higher and label stabilities were found to be similar compared with those obtained using {sup 111}In-tropolonate. High labelling efficiencies of neutrophils and lymphocytes were achieved with {sup 111}In complexes of pyranones. Tropolone was found to have a greater inhibitory effect on metalloenzymes and to cause greater impairment of platelet function than 3-hydroxy-6-propoxymethyl-4H-pyran-4-one. Thus 6-alkoxymethyl-3-hydroxy-4H-pyran-4-ones may have advantages over current ligands used in cell labelling with {sup 111}In. (orig.)

  3. 1,5-Anhydro-D-fructose as Chiral Building Block: A Novel Approach to 1-Deoxymannojirimycin

    DEFF Research Database (Denmark)

    Maier, Peter; Andersen, Søren Møller; Lundt, Inge

    2006-01-01

    A novel six-step synthesis of 1-deoxymannojirimycin from 1,5-anhydro-D-fructose in 35% overall yield is reported. The key steps are nucleophilic piperidine ring formation and subsequent Lewis acid induced pyran ether cleavage.......A novel six-step synthesis of 1-deoxymannojirimycin from 1,5-anhydro-D-fructose in 35% overall yield is reported. The key steps are nucleophilic piperidine ring formation and subsequent Lewis acid induced pyran ether cleavage....

  4. 9-(4-Hydroxy-3,5-dimethoxyphenyl-3,3,6,6-tetramethyl-3,4,5,6,7,9-hexahydro-1H-xanthene-1,8(2H-dione

    Directory of Open Access Journals (Sweden)

    V. Sughanya

    2012-04-01

    Full Text Available In the title compound, C25H30O6, the two fused cyclohexanone rings have envelope conformations, whereas the central pyran ring is roughly planar [mximum deviation = 0.045 (2 Å]. The pyran and benzene rings are almost perpendicular to each other, making a dihedral angle of 86.32 (2°. In the crystal, molecules are linked via pairs of O—H...O hydrogen bonds, forming inversion dimers.

  5. 6-Methyl-2-pyridyl N-acetyl-1-thio-β-d-glucosa-minide methanol monosolvate.

    Science.gov (United States)

    Chen, Bo; Guo, Miao; Jin, Wei-Hua; Wang, Yan-Wei; Liang, Hong-Ze

    2010-09-15

    In the title compound, C(14)H(20)N(2)O(5)S·CH(4)O, the pyran-ose and pyridine rings are linked through an S atom. The pyran-ose ring has a normal chair conformation. An intra-molecular O-H⋯N hydrogen bond occurs. Inter-molecular O-H⋯O, N-H⋯O, O-H⋯N and weak C-H⋯O hydrogen bonding is present in the crystal structure.

  6. Efficient Synthesis of 2-Amino-4-aryl-7,7-dimethyl-5-oxo-4H-5,6,7,8-tetrahydrobenzo[b]pyran-3-carboxylate in Aqueous Media%水介质中2-氨基-4-芳基-7,7-二甲基-5-氧代-4H-5,6,7,8-四氢苯并[b]吡喃-3-羧酸酯的有效合成

    Institute of Scientific and Technical Information of China (English)

    史达清; 张姝; 庄启亚

    2005-01-01

    水介质中在三乙基苄基氯化铵(TEBA)存在下,芳亚甲基氰乙酸酯与5,5-二甲基-1,3-环己二酮反应为2-氨基-4-芳基-7,7-二甲基-5-氧代-4H-5,6,7,8-四氢苯并[b]吡喃-3-羧酸酯提供了一种快速、方便、高效和洁净的合成方法.产物的结构通过红外光谱、核磁共振氢谱、元素分析和单晶X射线衍射确定.

  7. Clean Synthesis of 2-Amino-3-cyano-4-aryl-7,7-dimethyl-5-oxo-4H-5,6,7,8-tetrahydrobenzo [b] pyran in Water%水中2-氨基-3-氰基-4-芳基-7,7-二甲基-5-氧代-4H- 5,6,7,8-四氢苯并[b]吡喃的洁净合成

    Institute of Scientific and Technical Information of China (English)

    史达清; 张姝; 庄启亚; 屠树江; 胡宏纹

    2003-01-01

    在水溶剂中在三乙基苄基氯化铵(TEBA)存在下,取代肉桂腈与5,5-二甲基-1,3-环己酮反应为2-氨基-3-氰基-4-芳基-7,7-二甲基-5-氧代-4H-5,6,7,8-四氢苯并[b]吡喃提供了一种快速、方便、高效和洁净的合成方法.

  8. 阿西替尼中间体(E)-6-碘-3-(2-(吡啶-2-基)乙烯基)-1-(四氢-2H-吡喃-2-基)-1H-吲唑的合成研究%Study on Synthesis of (E)-6-Iodo-3-(2-(pyridine-2-yl)vinyl)-1-(tetrahydro-2H-pyran-2-yl)-1H-indazole

    Institute of Scientific and Technical Information of China (English)

    孟凡星; 张诗缇; 蔡东; 贾云宏

    2015-01-01

    (E)-6-碘-3-(2-(吡啶-2-基)乙烯基)-1-(四氢-2H-吡喃-2-基)-1H-吲唑是阿西替尼的关键中间体,以6-硝基-1H-吲唑为起始原料,经过碘代、加成、偶联、还原、碘代得到目标化合物.探讨了用微波辐射加热偶联反应的问题,并对各步反应合成条件进行了优化.改进后工艺总收率达42.32%(6-硝基-1H-吲唑为原料计),收率比文献报道值提高近5%,目标化合物和各中间体经1HNMR和MS等确证结构.改进后的工艺降低了成本,简单可行,适合工业化生产.

  9. Comparative Chemical Analysis of the Essential Oil Constituents in the Bark, Heartwood and Fruits of Cryptocarya massoy (Oken Kosterm. (Lauraceae from Papua New Guinea

    Directory of Open Access Journals (Sweden)

    David N. Leach

    2007-02-01

    Full Text Available Exhaustive hydro-distillation of the bark, heartwood and fruits of Cryptocarya massoy (Lauraceae afforded pale yellow-coloured oils in 0.7, 1.2 and 1.0 % yields, respectively. Detailed chemical evaluation of these distillates using GC/MS revealed the major components in the bark and the heartwood oils to be the C-10 (5,6-dihydro-6-pentyl-2H-pyran-2-one and C-12 (5,6-dihydro-6-heptyl-2H-pyran-2-one massoia lactones, while the major fruit oil constituent was benzyl benzoate (68.3 %. The heartwood also contained trace amounts of the C-14 (5,6-dihydro-6-nonyl-2H-pyran-2-one massoia lactone (1.4 % and the saturated C-10 derivative d-decalactone (2.5 %.

  10. Photochromic properties and reaction mechanism of naphthopyran

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The photochromic properties and reaction mechanism of title compounds have been examined with steady method on compounds 3-phenyl-3-[3-methylbenzothiophene-2-yl]-3H- naphtho[2,1-b]pyran (1) and 3-phenyl-3-[benzofuran-2-yl]-3H-naphtho[2,1-b]pyran (2) and nanosecond laser flash photolysis techniques on compound 3-phenyl-3-[1,2-dimethylindol-3-yl]- 3H-naphtho[2,1-b]pyran (3). The influence of oxygen on transient spectra and decay kinetics of compound 3 has been investigated. Both excited singlet state and triplet state are involved in the photochromic mechanism of compound 3. The influence of molecular structure on photochromic behavior has been studied also. Decay kinetics indicated that the lifetime of colored forms of 1 and 2 were several orders of magnitude longer than that of 3.

  11. Photochromic properties and reaction mechanism of naphthopyran

    Institute of Scientific and Technical Information of China (English)

    潘桂兰; 魏景强; 朱爱平; 明阳福; 樊美公; 姚思德

    2001-01-01

    The photochromic properties and reaction mechanism of title compounds have been examined with steady method on compounds 3-phenyl-3-[3-methylbenzothiophene-2-yl]-3H-naphtho[2,1-b]pyran (1) and 3-phenyl-3-[benzofuran-2-yl]-3H-naphtho[2,1-b]pyran (2) and nanosecond laser flash photolysis techniques on compound 3-phenyl-3-[1,2-dimethylindol-3-yl]-3H-naphtho[2,1-b]pyran (3). The influence of oxygen on transient spectra and decay kinetics of compound 3 has been investigated. Both excited singlet state and triplet state are involved in the photochromic mechanism of compound 3. The influence of molecular structure on photochromic behavior has been studied also. Decay kinetics indicated that the lifetime of colored forms of 1 and 2 were several orders of magnitude longer than that of 3.

  12. Methyl 2-(2,2-dimethyl-3a,6a-dihydrofuro[3,2-d][1,3]dioxol-5-yl-4-oxo-4H-chromene-3-carboxylate

    Directory of Open Access Journals (Sweden)

    Devadasan Velmurugan

    2013-08-01

    Full Text Available In the title molecule, C18H16O7, the dioxolane ring adopts an envelope conformation with the dimethyl-substituted C atom as the flap. The furan ring is almost coplanar with the pyran ring, with a dihedral angle of 1.04 (10° between the planes, and it makes a dihedral angle of 67.97 (11° with the mean plane of the dioxolane ring. The latter makes a dihedral angle of 67.15 (10° with the pyran ring. The O atom attached to the pyran ring deviates by −0.009 (1 Å. The crystal packing features C—H...O hydrogen bonds, forming a three-dimensional structure. The methoxycarbonyl atoms are disordered over two positions, with a refined occupancy ratio of 0.508 (18:0.492 (18.

  13. Fluorine effect on pericyclic and pseudopericyclic processes: Evidences and ab initio theory

    Indian Academy of Sciences (India)

    Lakshminarayanan Akilandeswari; Madhavan Jaccob; Ponnambalam Venuvanalingam

    2009-09-01

    Electrocyclic ring opening (ERO) reactions of 2-pyrone, 2-pyranol and pyran and their fluoro compounds (1-6) have been studied at MP2/6-31G() level with special emphasis on the influence of fluorine on these pericyclic/pseudopericyclic processes. Calculations clearly predict that substitution of fluorine at C6 favour the reaction both kinetically and thermodynamically. Magnetic susceptibility anisotropy (aniso), NICS(0), NBO and bond critical property (BCP) analyses clearly illustrate the following; 2-pyrone (1) and 6-fluoro-2-pyrone (2) reactions are pseudopericyclic; 6-fluoro-2-pyranol (reaction 4) corresponds to a borderline case; 2-pyranol (3) and pyran (5) and 6-fluoro pyran (6) reactions are clearly pericyclic in character. Correspondingly pseudeopericyclic reactions show up orbital disconnections and fluorine delays the occurrence of orbital disconnections on the reaction trajectory.

  14. 8-Chloro-4-oxo-4H-chromene-3-carbaldehyde.

    Science.gov (United States)

    Ishikawa, Yoshinobu

    2014-07-01

    In the title compound, C10H5ClO3, a chlorinated 3-formyl-chromone derivative, all atoms are essentially coplanar (r.m.s. deviation = 0.032 Å for the non-H atoms), with the largest deviation from the least-squares plane [0.0598 (14) Å] being for a pyran-ring C atom. In the crystal, mol-ecules are linked through stacking inter-actions along the b axis [shortest centroid-centroid distance between the pyran and benzene rings = 3.566 (2) Å].

  15. Indenopyrans – synthesis and photoluminescence properties

    Science.gov (United States)

    Diac, Andreea Petronela; Ţepeş, Ana-Maria; Soran, Albert; Grosu, Ion; Terec, Anamaria; Roncali, Jean

    2016-01-01

    Summary New indeno[1,2-c]pyran-3-ones bearing different substituents at the pyran moiety were synthesized and their photophysical properties were investigated. In solution all compounds were found to be blue emitters and the trans isomers exhibited significantly higher fluorescence quantum yields (relative to 9,10-diphenylanthracene) as compared to the corresponding cis isomers. The solid-state fluorescence spectra revealed an important red shift of λmax due to intermolecular interactions in the lattice, along with an emission-band broadening, as compared to the solution fluorescence spectra. PMID:27340473

  16. A two step facile synthesis of new steroidal linear and angular pyranones having anti-mycobacterial activity

    Institute of Scientific and Technical Information of China (English)

    Shams-uz-zaman; Tabassum Siddiqui; Mohd.Gulfam Alam; Najmul Islam

    2009-01-01

    Title compounds 2',2'-dimethylcholesta-2,4-dien[3,2-b]-pyran-4'-one(3),2',2'-dimethyl-3β-substituted cholesta-4,6-dien[7,6-b]-pyran-4'-one(6a,b)and(6c)were prepared by the cyclization of 2-acetylcholesta-2,4-dien-3-ol(2),6-acetyl-3β-substituted-cholesta-4,6-dien-7-ol(Sa,b)and(5c)respectively,with pyrrolidine,dry benzene and dry acetone using Dean Stark separator through conventional heating.Furthermore,compounds were also found to be active against Mycobacterium tuberculosis.

  17. rac-Dimethyl 2-(tert-butylamino-5-oxo-4,5-dihydropyrano[3,2-c]chromene-3,4-dicarboxylate

    Directory of Open Access Journals (Sweden)

    S. Antony Inglebert

    2011-11-01

    Full Text Available The title compound, C20H21NO7, is asymmetric with a chiral centre located in the pyran ring and crystallizes as a racemate. The molecular framework is somewhat bent; the coumarin moiety and the pyran ring are inclined by 7.85 (5°. The molecular structure is characterized by an intramolecular N—H...O hydrogen bond, which generates an S(6 ring motif, and the crystal packing is stabilized by intermolecular C—H...O hydrogen bonds. The 3-carboxylate O atom is involved in both of them, having a bifurcated character.

  18. 8-Chloro-4-oxo-4H-chromene-3-carbaldehyde

    Directory of Open Access Journals (Sweden)

    Yoshinobu Ishikawa

    2014-07-01

    Full Text Available In the title compound, C10H5ClO3, a chlorinated 3-formylchromone derivative, all atoms are essentially coplanar (r.m.s. deviation = 0.032 Å for the non-H atoms, with the largest deviation from the least-squares plane [0.0598 (14 Å] being for a pyran-ring C atom. In the crystal, molecules are linked through stacking interactions along the b axis [shortest centroid–centroid distance between the pyran and benzene rings = 3.566 (2 Å].

  19. Two new iridoids from roots of Patrinia scabra Bunge.

    Science.gov (United States)

    Liu, R H; Zhang, W D; Gu, Z B; Zhang, C; Su, J; Xu, X K

    2006-07-20

    Two new iridoids 1,3-dimethyloxy-7-hydroxymethyl-4-(3-methyl-butyryloxymethyl)-1-hydrocyclopenta-4,7-diene[c]pyran-6-one (1) and 1,3-dimethyloxy-7-hydroxymethyl-4-methyloxymethyl-1-hydrocyclopenta-4,7-diene[c]pyran-6-one (2) were isolated from the roots of Patrinia scabra Bunge. The structure elucidation of the isolated compounds was based primarily on HRESIMS, EIMS, IR, UV, 1D- and 2D-NMR analyses, including COSY, HMQC, HMBC and NOESY correlations, as well as X-ray crystallographic analysis.

  20. Ionic modified crosslinked salep: a highly loaded and efficient heterogeneous organocatalyst.

    Science.gov (United States)

    Pourjavadi, Ali; Hosseini, Seyed Hassan; Fakoorpoor, Seyed Mahmoud

    2013-02-15

    In this work, a novel heterogeneous organocatalyst was synthesized by immobilization of hydroxide ions on the modified salep as a natural polymer. Because of the grafting of ionic polymer chains onto the salep backbone, catalyst has high loading level of hydroxide ions (3.01 mmol/g). The resulting catalyst shows excellent activity in the synthesis of 4H-benzo[b]pyrans in water at room temperature in short reaction times. The present catalyst and protocol represent a simple, ecologically safe and cost-effective route to synthesize 4H-benzo[b]pyrans with high product yield, as well as easy catalyst recycling.

  1. Phenyl 2,3-O-isopropylidene-1-thio-α-d-rhamnopyranoside

    Directory of Open Access Journals (Sweden)

    Hasnah Osman

    2008-01-01

    Full Text Available In the title compound, C15H20O4S, a dioxolane ring is fused to the pyran ring of the sugar which carries a thiophenyl substituent on the anomeric C atom. The dioxolane ring adopts an envelope conformation and the pyran ring system a distorted 4C1 chair. The structure is stabilized by O—H...O hydrogen bonds, forming centrosymmetric dimers that generate an R22(10 ring motif. Additional C—H...O interactions form an extended network. Two C atoms of the phenyl ring are disordered over two positions; the site occupancy factors are ca. 0.7 and 0.3.

  2. 6-Methyl-2-pyridyl N-acetyl-1-thio-β-d-glucosa­minide methanol monosolvate

    Science.gov (United States)

    Chen, Bo; Guo, Miao; Jin, Wei-Hua; Wang, Yan-Wei; Liang, Hong-Ze

    2010-01-01

    In the title compound, C14H20N2O5S·CH4O, the pyran­ose and pyridine rings are linked through an S atom. The pyran­ose ring has a normal chair conformation. An intra­molecular O—H⋯N hydrogen bond occurs. Inter­molecular O—H⋯O, N—H⋯O, O—H⋯N and weak C—H⋯O hydrogen bonding is present in the crystal structure. PMID:21587547

  3. Liposomes as vehicles for water insoluble platinum-based potential drug

    DEFF Research Database (Denmark)

    Kaluđerović, Goran N; Dietrich, Andrea; Kommera, Harish

    2012-01-01

    Formulation of liposome delivery system loaded with water insoluble 2-(4-(tetrahydro-2H-pyran-2-yloxy)-undecyl)-propane-1,3-diamminedichloroplatinum(II), LipoTHP-C11 was carried out. The particle size distributions were determined by dynamic light scattering and asymmetrical flow field-flow fract...

  4. Scope and mechanism of the highly stereoselective metal-mediated domino aldol reactions of enolates with aldehydes

    Science.gov (United States)

    Engelen, Bernward; Panthöfer, Martin; Deiseroth, Hans-Jörg; Schlirf, Jens

    2016-01-01

    Summary A one-pot transformation, which involves the reaction of ketones with aldehydes in the presence of metal halides to furnish tetrahydro-2H-pyran-2,4-diols in a highly diastereoselective manner, is investigated thoroughly by experiments and computations. The reaction was also successfully implemented on a flow micro reactor system. PMID:27340472

  5. Synthesis and antimicrobial activities of some sulphur containing chromene derivatives.

    Science.gov (United States)

    Serbetçi, Tuba; Birteksöz, Seher; Prado, Soizic; Michel, Sylvie; Tillequin, François

    2012-07-01

    A series of 3,3-dimethyl-3Hbenzothieno[3,2-f][1]-benzopyran analogues modified at the pyran 1,2-double bond were synthesized. The corresponding dihydro and (+/-)-cis-diol derivatives were converted into diacetate and cyclic carbonate upon acylation. The title compounds were characterized by spectroscopic analysis and screened for their antimicrobial activity in vitro.

  6. 1-(5-Hydroxy-2,2,8,8-tetramethyl-2H,8H-pyrano[2,3-f]chromen-6-ylethanone

    Directory of Open Access Journals (Sweden)

    Sunayna Pawar

    2012-10-01

    Full Text Available In the title compound, C18H20O4,the pyran ring of the chromene unit adopts a half-chair conformation. An intramolecular O—H...O hydrogen bond occurs. In the crystal, molecules are linked along the b axis by C—H...O hydrogen bonds.

  7. Methyl 3-(4-isopropylphenyl-1-phenyl-3,3a,4,9b-tetrahydro-1H-chromeno[4,3-c]isoxazole-3a-carboxylate

    Directory of Open Access Journals (Sweden)

    J. Kanchanadevi

    2011-08-01

    Full Text Available In the title compound, C27H27NO4, the five-membered isoxazole ring adopts an envelope conformation and the six-membered pyran ring adopts a half-chair conformation. The dihedral angle between the mean planes of the isoxazole ring and the chromene ring system is 54.95 (4°.

  8. 2-Amino-4-[4-(dimethylaminophenyl]-5-oxo-5,6,7,8-tetrahydro-4H-chromene-3-carbonitrile

    Directory of Open Access Journals (Sweden)

    Yan Qiao

    2011-11-01

    Full Text Available In the title molecule, C18H19N3O2, the fused cyclohexenone and pyran rings adopt sofa conformations. Intermolecular N—H...N and N—H...O hydrogen bonds link molecules into corrugated layers parallel to the bc plane.

  9. Synthesis and studies of antibacterial activity of pongaglabol

    Indian Academy of Sciences (India)

    Sayed Alam; Zakaria Sarkar; Azizul Islam

    2004-01-01

    Pongaglabol [8-hydroxy-5-phenyl-furo[2,3-h]benzo(b)pyran-7-one] was synthesized and tested for antibacterial effects against Shigella dysenteriae, Salmonella typhi, Streptococcus -haemolyticus and Staphylococcus aureus. The synthesized compounds were characterized using UV, IR and 1H NMR spectral data.

  10. Crystal structure of 1-(8-meth-oxy-2H-chromen-3-yl)ethanone.

    Science.gov (United States)

    Koh, Dongsoo

    2014-09-01

    In the structure of the title compound, C12H12O3, the di-hydro-pyran ring is fused with the benzene ring. The di-hydro-pyran ring is in a half-chair conformation, with the ring O and methyl-ene C atoms positioned 1.367 (3) and 1.504 (4) Å, respectively, on either side of the mean plane formed by the other four atoms. The meth-oxy group is coplanar with the benzene ring to which it is connected [Cb-Cb-Om-Cm torsion angle = -0.2 (4)°; b = benzene and m = meth-oxy], and similarly the aldehyde is coplanar with respect to the double bond of the di-hydro-pyran ring [Cdh-Cdh-Ca-Oa = -178.1 (3)°; dh = di-hydro-pyran and a = aldehyde]. In the crystal, mol-ecules are linked by weak meth-yl-meth-oxy C-H⋯O hydrogen bonds into supra-molecular chains along the a-axis direction.

  11. Efficacy of Ambruticin Analogs in a Murine Model of Coccidioidomycosis

    OpenAIRE

    Shubitz, Lisa F.; Galgiani, John N.; Tian, Zong-Qiang; Zhong, Ziyang; Timmermans, Pieter; Katz, Leonard

    2006-01-01

    Ambruticin S, an antifungal cyclopropyl-pyran acid, showed curative effects against murine coccidioidal infection. Two analogs of this compound with greater in vitro potency were tested against lethal murine Coccidioides infection. Both improved the survival of mice over that of controls; one resulted in near-sterilization of infection.

  12. Gal3 Catalyzed Tetrahydropyranylation of Alcohols and Phenols

    Institute of Scientific and Technical Information of China (English)

    SUN, Pei-Pei(孙培培); HU, Zhi-Xin(胡志新)

    2004-01-01

    In dichloromethane, the nucleophilic addition of alcohols or phenols to 3,4-dihydro-2H-pyran (DHP) was catalyzed effectively by gallium triiodide which was generated in situ by the reaction of gallium metal and iodine to give the corresponding tetrahydropyranyl acetals in good to excellent yields.

  13. Investigating the Influence of Karrikins on Seed Germination

    Science.gov (United States)

    de Beer, Josef

    2012-01-01

    Recent research has identified a karrikin (a butenolide derative) known as 3-methyl-2H-furo[2,3-c]pyran-2-one, formed from burning cellulose, that stimulates seed germination. Here, I present ideas on how to investigate the influence of karrikins on seed germination in the laboratory.

  14. Synthesis of furo[3,2-c ]- and pyrano[ 3,2-c ] quinolines by lanthanide triflate catalyzed imino-Diels-Alder reaction

    Institute of Scientific and Technical Information of China (English)

    MA, Yun(马云); QIAN, Chang-Tao(钱长涛); SUN, Jie(孙杰); XIE, Mei-Hua(谢美华)

    2000-01-01

    Imino Diels-Alder reaction of imines witth 2,3-dihydrofuran or 3,4-dihydro-2H-pyran proceeded smothly in the presence of a catalytic amount (0.5 mol %) of ytterbium triflate to afford furo[3,2-c]- and pyrano[3,2-c] quinolines conveniently in high yield.

  15. A Research-Based Undergraduate Organic Laboratory Project: Investigation of a One-Pot, Multicomponent, Environmentally Friendly Prins-Friedel-Crafts-Type Reaction

    Science.gov (United States)

    Dintzner, Matthew R.; Maresh, Justin J.; Kinzie, Charles R.; Arena, Anthony F.; Speltz, Thomas

    2012-01-01

    Students in the undergraduate organic laboratory synthesize tetrahydro-2-(4-nitrophenyl)-4-phenyl-2"H"-pyran via the Montmorillonite K10 clay-catalyzed reaction of p-nitrobenzaldehye with methanol, 3-buten-1-ol, and benzene. The synthesis comprises an environmentally friendly tandem Prins-Friedel-Crafts-type multicomponent reaction (MCR) and sets…

  16. One-pot three-component synthesis of spirooxindoles catalyzed by nano Ag/kaolin

    Directory of Open Access Journals (Sweden)

    Bahareh Sadeghi

    2015-06-01

    Full Text Available Nano Ag/kaolin has been used as an effective heterogeneous catalyst for one-pot synthesis of spiro[4H-pyran-3,3'-oxindoles] via reaction of isatin derivatives, malononitrile and cyclic 1,3-diketones under mild reaction conditions in excellent yields.

  17. Investigating the Influence of Karrikins on Seed Germination

    Science.gov (United States)

    de Beer, Josef

    2012-01-01

    Recent research has identified a karrikin (a butenolide derative) known as 3-methyl-2H-furo[2,3-c]pyran-2-one, formed from burning cellulose, that stimulates seed germination. Here, I present ideas on how to investigate the influence of karrikins on seed germination in the laboratory.

  18. Synthesis of 2-Alkyl(aryl)-3-methylthio-6-methyl-6-arylpyrano-[4, 3-c] pyrazol-4(2H)-ones

    Institute of Scientific and Technical Information of China (English)

    Yu Xin LI; You Ming WANG; Xiao Ping YANG; Su Hua WANG; Zheng Ming LI

    2004-01-01

    The synthesis of 2-alkyl(aryl)-3-methylthiopyrano[4,3-c]pyrazol-4(2H)-ones via 5, 6-dihydro-2H-pyran-2, 4-dione-3-dithioacetals with (un)substituted hydrazines is described and the mechanism of the formation of title compounds is discussed. Their structures were confirmed by 1HNMR spectra and elemental analysis.

  19. 3,4,6-Tri-O-acetyl-1,2-[(S-ethylidene]-β-d-mannopyranose

    Directory of Open Access Journals (Sweden)

    Henok H. Kinfe

    2012-08-01

    Full Text Available In the title compound, C14H20O9, the six-membered pyran and the five-membered dioxalane rings adopt chair and twisted conformations, respectively. In the crystal, the molecules are linked by C—H...O interactions.

  20. Synthesis and Crystal Structure of Ethyl 2-amino-7,7-dimethyl-4-(4′-fluorophenyl)-5-oxo-5,6,7,8-tetrahydro-4H -benzo[b]pyran-2-carboxylate in Water%水相中2-氨基-7,7-二甲基-4-对氟苯基-5-氧代-5,6,7,8-四氢-4H-苯并吡喃-2-甲酸乙酯的合成和晶体结构

    Institute of Scientific and Technical Information of China (English)

    庄启亚; 张姝; 史达清; 屠树江; 王香善

    2003-01-01

    标题化合物C20H22FNO4由4-氟苯亚甲基氰乙酸乙酯和5,5-二甲基-1,3-环己二酮在三乙基苄基氯化铵(TEBA)存在下在水中加热反应而得,结构通过单晶X射线衍射法确定,其晶体属三斜晶系,空间群 P-1, Mr=359.39, a=0.826 6(1) nm, b=0.977 3(1) nm, c=1.237 5(2) nm, α=81.40(1)°,β=73.41(1)°,γ=82.15(1)°,V=0.942 6(2) nm3,Z=2,Dc=1.266g*mm-3,μ=0.094 mm-1,F(000)=380, 最终的偏离因子为R=0.040 3, Rw=0.105 7, 在分子结构中平面1(苯环)与平面2 (C(8)、C(13)、C(14)、C(15)) 之间的二面角为89.56°,平面2与平面3 (C(8)、C(9)、C(10)、C(12)、C(13)) 之间的二面角为13.37°,平面1与平面3之间的二面角为102.70°.吡喃环为船式构象,而与吡喃环稠合的六元环为信封式构象.

  1. Estudo do comportamento fotocrómico de um naftopirano: uma experiência simples ilustrativa do fotocromismo

    Directory of Open Access Journals (Sweden)

    Coelho Paulo J.

    2006-01-01

    Full Text Available An easy experiment on the synthesis of 3,3-diphenyl-3H-naphtho[2,1-b]pyran and characterization of its photochromic behaviour is reported. Upon irradiation of an uncoloured toluene solution of 3,3-diphenyl-3H-naphtho[2,1-b]pyran with near UV light, an intense yellow colouration is produced due to the formation of two coloured open forms. When the irradiation source is removed the coloured open forms return to the uncoloured state. The analysis of the absorbance decay with time allows the determination of the discoloration rate constants of each open form. The reversibility of the photochromic phenomenon, well demonstrated by the exposure of the solution to sunlight for a few seconds, is particularly attractive to the students.

  2. Total synthesis of bryostatin 1.

    Science.gov (United States)

    Keck, Gary E; Poudel, Yam B; Cummins, Thomas J; Rudra, Arnab; Covel, Jonathan A

    2011-02-02

    Bryostatin 1 is a marine natural product that is a very promising lead compound because of the potent biological activity it displays against a variety of human disease states. We describe herein the first total synthesis of this agent. The synthetic route adopted is a highly convergent one in which the preformed, heavily functionalized pyran rings A and C are united by "pyran annulation", the TMSOTf-promoted reaction between a hydroxyallylsilane appended to the A-ring fragment and an aldehyde contained in the C-ring fragment, with concomitant formation of the B ring. Further elaborations of the resulting very highly functionalized intermediate include macrolactonization and selective cleavage of just one of five ester linkages present.

  3. Surprising Coordination Geometry Differences in Ce(IV)- and Pu(IV)-Maltol Complexes

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence Berkeley National Laboratory; Raymond, Kenneth; Szigethy, Geza; Xu, Jide; Gorden, Anne E.V.; Teat, Simon J.; Shuh, David K.; Raymond, Kenneth N.

    2008-02-12

    As part of a study to characterize the detailed coordination behavior of Pu(IV), single crystal X-ray diffraction structures have been determined for Pu(IV) and Ce(IV) complexes with the naturally-occurring ligand maltol (3-hydroxy-2-methyl-pyran-4-one) and its derivative bromomaltol (5-bromo-3-hydroxy-2-methyl-pyran-4-one). Although Ce(IV) is generally accepted as a structural analog for Pu(IV), and the maltol complexes of these two metals are isostructural, the corresponding bromomaltol complexes are strikingly different with respect to ligand orientation about the metal ion: All complexes exhibit trigonal dodecahedral coordination geometry but the Ce(IV)-bromomaltol complex displays an uncommon ligand arrangement not mirrored in the Pu(IV) complex, although the two metal species are generally accepted to be structural analogs.

  4. A triclinic polymorph of (-)-(S)-N-benzyl-2-[(R)-6-fluoro-chroman-2-yl]-2-hy-droxy-ethanaminium bromide.

    Science.gov (United States)

    Rousselin, Yoann; Laureano, Hugo; Clavel, Alexandre

    2013-12-01

    The title salt, C18H21FNO2 (+)·Br(-), determined at 115 K, crystallizes in the triclinic space group P1. The previously reported polymorph occurs in the monoclinic space group P21 and has two independent mol-ecules in the asymmetric unit [Peeters et al. (1993 ▶). Acta Cryst. C49, 2157-2160]. In the title molecule, the pyran rings adopt half-chair conformations. The absolute configuration is S for the hy-droxy-bearing C atom and R for the asymmetric C atom in the di-hydro-pyran unit. In the crystal, the components are linked by N-H⋯Br and O-H⋯Br hydrogen bonds, forming chains along the c-axis direction. The crystal studied was refined as an inversion twin.

  5. Crystal structure of 3-acetyl-4H-chromen-4-one

    Directory of Open Access Journals (Sweden)

    Yoshinobu Ishikawa

    2015-07-01

    Full Text Available In the title compound, C11H8O3, the fused-ring system is almost planar (r.m.s. deviation = 0.020 Å, with the largest deviation from the least-squares plane [0.0462 (17 Å] being for a pyran C atom. The dihedral angle between the plane of the fused-ring system and acetyl plane is 5.149 (16°. In the crystal, the fused rings are linked by aromatic π–π stacking interactions [centroid–centroid distance between the benzene and pyran rings = 3.643 (6 Å] and C—H...O hydrogen bonds, generating a three-dimensional network.

  6. 5-Methylspiro[indoline-3,7′-[6H,7H,8H]pyrano[3,2-c:5,6-c′]di[1]benzopyran]-2,6′,8′-trione chloroform hemisolvate

    Directory of Open Access Journals (Sweden)

    Abdulrahman I. Almansour

    2012-04-01

    Full Text Available In the title compound, C27H15NO6·0.5CHCl3, the central pyran ring and both the benzopyran systems are planar, with the dihedral angle between the outer rings being 3.24 (6°. The indolin-2-one system is in a perpendicular configuration with respect to the pyran ring [dihedral angle = 87.58 (2°]. Supramolecular layers in the ac plane are formed in the crystal structure whereby inversion-related molecules are connected by N—H...O hydrogen bonds. These are further linked by C—H...O interactions, forming a supramolecular layer in the ac plane. Disordered CHCl3 solvent in the structure was modelled with the SQUEEZE routine in PLATON [Spek (2009. Acta Cryst. D65, 148–155].

  7. Coumarins from the leaves of Bambusa pervariabilis McClure.

    Science.gov (United States)

    Sun, Jia; Yue, Yong-De; Tang, Feng; Guo, Xue-Feng

    2010-03-01

    A new pyrone-coumarin, 7,8-dihydroxy-3-(3-hydroxy-4-oxo-4H-pyran-2-yl)-2H-chromen-2-one (1), along with two known coumarins, scopoletin (2) and scopolin (3), was isolated from the 95% EtOH extract of the leaves of Bambusa pervariabilis McClure. Their structures were determined on the basis of spectroscopic techniques and chemical methods.

  8. (6-Bromo-2-oxo-2H-chromen-4-ylmethyl diethylcarbamodithioate

    Directory of Open Access Journals (Sweden)

    M. Vinduvahini

    2016-01-01

    Full Text Available In the title compound, C15H16BrNO2S2, the 2H-chromene ring system is nearly planar, with a maximum deviation of 0.0182 (22 Å. In the crystal, π–π interactions between pyran and benzene rings of chromene [shortest centroid–centroid distance = 3.7588 (14 Å] occur.

  9. A modular approach to marine macrolide construction. 4. Assembly of C36-C51 and C29-C44 building blocks and evaluation of key coupling reactions targeting spongistatin 1 (altohyrtin A).

    Science.gov (United States)

    Ciblat, Stephane; Kim, Jungchul; Stewart, Catherine A; Wang, Jizhou; Forgione, Pat; Clyne, Dean; Paquette, Leo A

    2007-02-15

    Routes have been developed for the stereocontrolled elaboration of two highly functionalized sectors of spongistatin 1. The approach to ring F takes advantage of B-alkyl Suzuki-Miyaura coupling to install the C44-C45 bond. The E-ring pyran moiety was generated by acylation of an alpha-sulfonyl carbanion, the stereogenic centers of which were incorporated by sequential asymmetric aldol reactions. [structure: see text].

  10. Novel secoiridoid lactones from Jasminum multiflorum.

    Science.gov (United States)

    Shen, Y C; Chen, C H

    1989-01-01

    Four new secoiridoid lactones, jasmolactones A [1], B [2], C [3], and D [4], were isolated from the aerial part of Jasminum multiflorum. The structures of these compounds, which contain a novel bicyclic 2-oxo-oxepano[4,5-c]pyran ring system, were established by spectral analyses and chemical correlations. Pharmacological testing revealed that jasmolactones B and D possess coronary vasodilating and cardiotropic activities.

  11. Molecular design of donor-acceptor dyes for efficient dye-sensitized solar cells I: a DFT study.

    Science.gov (United States)

    El-Shishtawy, Reda M; Asiri, Abdullah M; Aziz, Saadullah G; Elroby, Shaaban A K

    2014-06-01

    Dye-sensitized solar cells (DSSCs) have drawn great attention as low cost and high performance alternatives to conventional photovoltaic devices. The molecular design presented in this work is based on the use of pyran type dyes as donor based on frontier molecular orbitals (FMO) and theoretical UV-visible spectra in combination with squaraine type dyes as an acceptor. Density functional theory has been used to investigate several derivatives of pyran type dyes for a better dye design based on optimization of absorption, regeneration, and recombination processes in gas phase. The frontier molecular orbital (FMO) of the HOMO and LUMO energy levels plays an important role in the efficiency of DSSCs. These energies contribute to the generation of exciton, charge transfer, dissociation and exciton recombination. The computations of the geometries and electronic structures for the predicted dyes were performed using the B3LYP/6-31+G** level of theory. The FMO energies (EHOMO, ELUMO) of the studied dyes are calculated and analyzed in the terms of the UV-visible absorption spectra, which have been examined using time-dependent density functional theory (TD-DFT) techniques. This study examined absorption properties of pyran based on theoretical UV-visible absorption spectra, with comparisons between TD-DFT using B3LYP, PBE, and TPSSH functionals with 6-31+G (d) and 6-311++G** basis sets. The results provide a valuable guide for the design of donor-acceptor (D-A) dyes with high molar absorptivity and current conversion in DSSCs. The theoretical results indicated 4-(dicyanomethylene)-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran dye (D2-Me) can be effectively used as a donor dye for DSSCs. This dye has a low energy gap by itself and a high energy gap with squaraine acceptor type dye, the design that reduces the recombination and improves the photocurrent generation in solar cell.

  12. Electrochemical selenium- and iodonium-initiated cyclisation of hydroxy-functionalised 1,4-dienes

    Directory of Open Access Journals (Sweden)

    Philipp Röse

    2015-01-01

    Full Text Available The cobalt(I-catalysed 1,4-hydrovinylation reaction of allyloxytrimethylsilane and allyl alcohol with substituted 1,3-dienes leads to hydroxy-functionalised 1,4-dienes in excellent regio- and diastereoselective fashion. Those 1,4-dienols can be converted into tetrahydrofuran and pyran derivatives under indirect electrochemical conditions generating selenium or iodonium cations. The reactions proceed in good yields and regioselectivities for the formation of single diastereomers.

  13. (1R,1′R,3S,3′S-5,5′,10,10′-Tetramethoxy-1,1′,3,3′-tetramethyl-3,3′,4,4′-tetrahydro-1H,1′H-8,8′-bi[benzo[g]isochromene

    Directory of Open Access Journals (Sweden)

    Margaret A. Brimble

    2008-04-01

    Full Text Available In the title compound, C34H38O6, the methyl groups on each pyran ring exhibit 1,3-cis stereochemistry, established during synthesis by pseudo-axial delivery of hydride during a lactol reduction step. In the crystal structure, the molecule lies on a twofold rotation axis and the torsion angle about the central diaryl bond is 41.3 (1°. The molecules pack in a herringbone arrangement.

  14. 6-Methyl-4-oxo-4H-chromene-3-carbaldehyde

    Directory of Open Access Journals (Sweden)

    Sammer Yousuf

    2012-10-01

    Full Text Available In the title compound, C11H8O3, the benzopyran-4-one or chromone ring system is almost planar, with a maximum deviation of 0.045 (2 Å. The crystal structure is stablized by π–π interactions between the benzene and pyran rings of inversion-related molecules stacked along the b axis, with a centroid–centroid distance of 3.5463 (12 Å

  15. 6′-Amino-3′-methyl-11H,2′H-spiro[indeno[1,2-b]quinoxaline-11,4′-pyrano[2,3-c]pyrazole]-5′-carbonitrile ethanol monosolvate

    Directory of Open Access Journals (Sweden)

    Jia Zheng

    2012-07-01

    Full Text Available In the title spiroindenoquinoxaline compound, C22H14N6O·C2H6O, the five-membered ring of the indene unit and the pyran ring are perpendicular [89.11 (3°]. In the crystal, N—H...N hydrogen bonds connect the spiroindenoquinoxaline molecules, and the ethanol solvent molecules complete the hydrogen-bond network via O—H...N and N—H...O interactions.

  16. Development of fast switching photochromic coatings on transparent plastics and glass

    OpenAIRE

    Mennig, Martin; Fries, Kira; Lindenstruth, Marion; Schmidt, Helmut K.

    1999-01-01

    A new photochromic organic-inorganic nanocomposite (Nanomer(R)) coating system has been developed. It is based on an epoxysilane as network former, an organic bisepoxide as spacer, an organic amine as thermal cross-linker and surface modified SiO2 nanoparticles as fillers. This coating system is compatible with different photochromic dyes, like oxazines and pyrans. Photochromic coatings with blue, yellow, red, green, violet and neutral tints were prepared on flat glass and PMMA substrates by ...

  17. Determination of the Thermodegradation of deoxyArbutin in Aqueous Solution by High Performance Liquid Chromatography

    OpenAIRE

    Chih-Chien Lin; Chao-Hsun Yang; Yi-Shyan Chen; Willy W. L. Hong; Jeng-Shiow Lai

    2010-01-01

    Tyrosinase is the key and rate-limiting enzyme responsible for the conversion of tyrosine into melanin. Competitive inhibition of tyrosinase enzymatic activity results in decreased or absent melanin synthesis by melanocytes in human skin. DeoxyArbutin (4-[(tetrahydro-2H-pyran-2-yl)oxy]phenol), a novel skin whitening agent, was synthesized through the removal of hydroxyl groups from the glucose side-chain of arbutin. DeoxyArbutin not only shows greater inhibition of tyrosinase activity but is ...

  18. Pomegranate Ellagitannin-Derived Compounds Exhibit Anti-proliferative and Anti-aromatase Activity in Breast Cancer Cells In Vitro

    OpenAIRE

    Adams, Lynn S.; Zhang, Yanjun; Seeram, Navindra P.; Heber, David; Chen, Shiuan

    2010-01-01

    Estrogen stimulates the proliferation of breast cancer cells and the growth of estrogen-responsive tumors. The aromatase enzyme, which converts androgen to estrogen, plays a key role in breast carcinogenesis. The pomegranate fruit, a rich source of ellagitannins (ETs), has attracted recent attention due to its anti-cancer and anti-atherosclerotic properties. On consumption, pomegranate ETs hydrolyze, releasing ellagic acid (EA) which is then converted to 3,8-dihydroxy-6H-dibenzo[b,d]pyran-6-o...

  19. Copper methanesulfonate-acetic acid as a novel catalytic system for tetrahydropyranylation of alcohols and phenols

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A synergistic catalytic effect between copper methanesulfonate and acetic acid in tetrahydropyranylation of alcohols and phenol at room temperature under solvent free condition has been described. Both alcohols (primary, secondary and tertiary) and phenols reacted with 3,4-dihydro-2H-pyran smoothly to afford the corresponding tetrahydropyranyl ethers in good yields.(C) 2007 Min Wang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

  20. 'Unconventional' coordination chemistry by metal chelating fragments in a metalloprotein active site.

    Science.gov (United States)

    Martin, David P; Blachly, Patrick G; Marts, Amy R; Woodruff, Tessa M; de Oliveira, César A F; McCammon, J Andrew; Tierney, David L; Cohen, Seth M

    2014-04-01

    The binding of three closely related chelators: 5-hydroxy-2-methyl-4H-pyran-4-thione (allothiomaltol, ATM), 3-hydroxy-2-methyl-4H-pyran-4-thione (thiomaltol, TM), and 3-hydroxy-4H-pyran-4-thione (thiopyromeconic acid, TPMA) to the active site of human carbonic anhydrase II (hCAII) has been investigated. Two of these ligands display a monodentate mode of coordination to the active site Zn(2+) ion in hCAII that is not recapitulated in model complexes of the enzyme active site. This unprecedented binding mode in the hCAII-thiomaltol complex has been characterized by both X-ray crystallography and X-ray spectroscopy. In addition, the steric restrictions of the active site force the ligands into a 'flattened' mode of coordination compared with inorganic model complexes. This change in geometry has been shown by density functional computations to significantly decrease the strength of the metal-ligand binding. Collectively, these data demonstrate that the mode of binding by small metal-binding groups can be significantly influenced by the protein active site. Diminishing the strength of the metal-ligand bond results in unconventional modes of metal coordination not found in typical coordination compounds or even carefully engineered active site models, and understanding these effects is critical to the rational design of inhibitors that target clinically relevant metalloproteins.

  1. Crystal structure of 7,8-dichloro-4-oxo-4H-chromene-3-carbaldehyde

    Directory of Open Access Journals (Sweden)

    Yoshinobu Ishikawa

    2015-08-01

    Full Text Available In the title compound, C10H4Cl2O3, a dichlorinated 3-formylchromone derivative, the fused-ring system is slightly puckered [dihedral angle between the benzene and pyran rings = 3.66 (10°]. The dihedral angle between the pyran ring and the formyl plane is 8.64 (7°. In the crystal, molecules are linked through π–π stacking interactions [centroid–centroid distance between the benzene and pyran rings = 3.727 (2 Å], C—H...O hydrogen bonds and short C...O contacts [2.838 (4 Å]. Halogen bonds between the formyl O atoms and the Cl atoms at the 7-position [Cl...O = 2.984 (3 Å, C—Cl...O = 170.83 (12° and Cl...O—C = 116.05 (19°] are also formed along the a axis, resulting in helical structures constructed by C—H...O hydrogen bonds and Cl...O halogen bonds along the b axis. In addition, type II halogen–halogen contacts between the chlorine atoms at the 7- and 8-positions [Cl...Cl = 3.519 (2 Å, C–Cl...Cl = 171.24 (10° and 88.74 (11°] are observed.

  2. The monoterpenes of Artemisia tridentata ssp. vaseyana, Artemisia cana ssp. viscidula and Artemisia tridentata ssp. spiciformis.

    Science.gov (United States)

    Gunawardena, K; Rivera, S B; Epstein, W W

    2002-01-01

    Monoterpenes from three different members of the Anthemideae family, Artemisia tridentata ssp. vaseyana, Artemisia cana ssp. viscidula and Artemisia tridentata ssp. spiciformis were isolated and their structures determined using spectroscopic techniques. A total of 26 irregular and regular monoterpenes were identified. Among these, 20 had previously been identified in the Anthemideae family. Of the remaining six, four were known, but previously unidentified in this family. 2,2-Dimethyl-6-isopropenyl-2H-pyran, 2,3-dimethyl-6-isopropyl-4H-pyran and 2-isopropenyl-5-methylhexa-trans-3,5-diene-1-ol were isolated from both A. tridentata ssp. vaseyana and A. cana ssp. viscidula. The irregular monoterpene 2,2-dimethyl-6-isopropenyl-2H-pyran has a carbon skeleton analogous to the biologically important triterpene squalene. Two additional irregular monoterpenes, artemisia triene and trans-chrysanthemal were isolated from A. cana ssp. viscidula and lavandulol was isolated from A. tridentata ssp. spiciformis. This is the first time a compound possessing a lavandulyl-skeletal type has been found in the Anthemideae family.

  3. Solvent-Dependent Pyranopterin Cyclization in Molybdenum Cofactor Model Complexes.

    Science.gov (United States)

    Williams, Benjamin R; Gisewhite, Douglas; Kalinsky, Anna; Esmail, Alisha; Burgmayer, Sharon J Nieter

    2015-09-08

    The conserved pterin dithiolene ligand that coordinates molybdenum (Mo) in the cofactor (Moco) of mononuclear Mo enzymes can exist in both a tricyclic pyranopterin dithiolene form and as a bicyclic pterin-dithiolene form as observed in protein crystal structures of several bacterial molybdoenzymes. Interconversion between the tricyclic and bicyclic forms via pyran scission and cyclization has been hypothesized to play a role in the catalytic mechanism of Moco. Therefore, understanding the interconversion between the tricyclic and bicyclic forms, a type of ring-chain tautomerism, is an important aspect of study to understand its role in catalysis. In this study, equilibrium constants (K(eq)) as well as enthalpy, entropy, and free energy values are obtained for pyran ring tautomerism exhibited by two Moco model complexes, namely, (Et4N)[Tp*Mo(O)(S2BMOPP)] (1) and (Et4N)[Tp*Mo(O)(S2PEOPP)] (2), as a solvent-dependent equilibrium process. Keq values obtained from (1)H NMR data in seven deuterated solvents show a correlation between solvent polarity and tautomer form, where solvents with higher polarity parameters favor the pyran form.

  4. Chenopodolans A-C: phytotoxic furopyrans produced by Phoma chenopodiicola, a fungal pathogen of Chenopodium album.

    Science.gov (United States)

    Cimmino, Alessio; Andolfi, Anna; Zonno, Maria Chiara; Avolio, Fabiana; Berestetskiy, Alexander; Vurro, Maurizio; Evidente, Antonio

    2013-12-01

    Three tetrasubstituted furopyrans, named chenopodolans A-C, were isolated together with the well known fungal metabolite (-)-(R)-6-hydroxymellein from the liquid culture of Phoma chenopodiicola, a fungal pathogen proposed for the biological control of Chenopodium album, a common worldwide weed of arable crops. The structures of chenopodolans A-C were established by spectroscopic and chemical methods as 2-(3-methoxy-2,6-dimethyl-7aH-furo[2,3-b]pyran-4-yl)-butane-2,3-diol, 1-(3-methoxy-2,6-dimethyl-7aH-furo[2,3-b]pyran-4-yl)ethanol and 3-methoxy-2,6-dimethyl-4-(1-methylpropenyl)-7aH-furo[2,3-b]pyran, respectively. The absolute configuration R to the hydroxylated secondary carbon (C-11) of the side chain at C-4 of chenopodolan A was determined by applying an advanced Mosher's method. Assayed by leaf puncture on host and non-host weeds chenopodolans A and B, and the 11-O-acetylchenopodolan A showed a strong phytotoxicity. These results showed that the nature of the side chain attached to C-4 is an important feature for the phytotoxicity. A weak zootoxic activity was only showed by chenopodolan B.

  5. Polyethyleneimine-modified superparamagnetic Fe{sub 3}O{sub 4} nanoparticles: An efficient, reusable and water tolerance nanocatalyst

    Energy Technology Data Exchange (ETDEWEB)

    Khoobi, Mehdi [Department of Medicinal Chemistry, Faculty of Pharmacy and Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences, Tehran 14176 (Iran, Islamic Republic of); Delshad, Tayebeh Modiri [Department of Chemistry, Islamic Azad University, Tehran-North Branch, Zafar St., Tehran (Iran, Islamic Republic of); Vosooghi, Mohsen; Alipour, Masoumeh [Department of Medicinal Chemistry, Faculty of Pharmacy and Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences, Tehran 14176 (Iran, Islamic Republic of); Hamadi, Hosein [Department of Chemistry, College of Science, Shahid Chamran University, Ahvaz (Iran, Islamic Republic of); Alipour, Eskandar [Department of Chemistry, Islamic Azad University, Tehran-North Branch, Zafar St., Tehran (Iran, Islamic Republic of); Hamedani, Majid Pirali [Iran Polymer and Petrochemical Institute, P.O. Box 14965/115, Tehran (Iran, Islamic Republic of); Sadat ebrahimi, Seyed Esmaeil [Department of Medicinal Chemistry, Faculty of Pharmacy and Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences, Tehran 14176 (Iran, Islamic Republic of); Safaei, Zahra [Department of Chemistry, Islamic Azad University, Tehran-North Branch, Zafar St., Tehran (Iran, Islamic Republic of); Foroumadi, Alireza [Department of Medicinal Chemistry, Faculty of Pharmacy and Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences, Tehran 14176 (Iran, Islamic Republic of); Shafiee, Abbas, E-mail: ashafiee@ams.ac.ir [Department of Medicinal Chemistry, Faculty of Pharmacy and Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences, Tehran 14176 (Iran, Islamic Republic of)

    2015-02-01

    A novel magnetically separable catalyst was prepared based on surface modification of Fe{sub 3}O{sub 4} magnetic nanoparticle (MNPs) with polyethyleneimine (PEI) via covalent bonding. [3-(2,3-Epoxypropoxy)propyl]trimethoxysilane (EPO) was used as cross linker to bond PEI on the surface of MNPs with permanent stability in contrast to PEI coating via electrostatic interactions. The synthesized catalyst was characterized by Fourier transform infrared (FT-IR), thermogravimetric analysis (TGA), X-ray powder diffraction (XRD), transmission electron microscopy (TEM) and vibrating sample magnetometry (VSM). The catalyst show high efficiency for one-pot synthesis of 2-amino-3-cyano-4H-pyran derivatives via multi-component reaction (MCR). This procedure offers the advantages of green reaction media, high yield, short reaction time, easy purification of the products and simple recovery and reuse of the catalyst by simple magnetic decantation without significant loss of catalytic activity. - Graphical abstract: Covalently grafted polyethyleneimine on Fe{sub 3}O{sub 4} magnetic nanoparticles as easily reusable catalyst for the synthesis of various 4H-pyrans. - Highlights: • Polyethyleneimine modified Fe{sub 3}O{sub 4} via covalent bonding as a novel water tolerance catalyst. • The catalyst showed high efficiency for one-pot synthesis of 2-amino-3-cyano-4H-pyrans in water. • Catalysts could be easily recovered and reused for several times without a significant loss in their catalytic activity.

  6. Pyranone natural products as inspirations for catalytic reaction discovery and development.

    Science.gov (United States)

    McDonald, Benjamin R; Scheidt, Karl A

    2015-04-21

    Natural products continue to provide a wealth of opportunities in the areas of chemical and therapeutic development. These structures are effective measuring sticks for the current state of chemical synthesis as a field and constantly inspire new approaches and strategies. Tetrahydropryans and tetrahydropyran-4-ones are found in numerous bioactive marine natural products and medicinal compounds. Our interest in exploring the therapeutic potential of natural products containing these motifs provided the impetus to explore new methods to access highly functionalized, chiral pyran molecules in the most direct and rapid fashion possible. This goal led to exploration and development of a Lewis acid-mediated Prins reaction between a chiral β-hydroxy-dioxinone and aldehyde to produce a pyran-dioxinone fused product that can be processed in a single pot operation to the desired tetrahydropyran-4-ones in excellent yield and stereoselectivity. Although the Prins reaction is a commonly employed approach toward pyrans, this method uniquely provides a 3-carboxy-trisubstituted pyran and utilizes dioxinones in a manner that was underexplored at the time. The 3-carboxy substituent served as a key synthetic handhold when this method was applied to the synthesis of highly functionalized pyrans within the macrocyclic natural products neopeltolide, okilactiomycin, and exiguolide. When employed in challenging macrocyclizations, this tetrahydropyranone forming reaction proved highly stereoselective and robust. Another major thrust in our lab has been the synthesis of benzopyranone natural products, specifically flavonoids, because this broad and diverse family of compounds possesses an equally broad range of biological and medicinal applications. With the goal of developing a broad platform toward the synthesis of enantioenriched flavonoid analogs and natural products, a biomimetic, asymmetric catalytic approach toward the synthesis of 2-aryl benzopyranones was developed. A

  7. Vicinal 1H-1H NMR coupling constants from density functional theory as reliable tools for stereochemical analysis of highly flexible multichiral center molecules.

    Science.gov (United States)

    López-Vallejo, Fabian; Fragoso-Serrano, Mabel; Suárez-Ortiz, Gloria Alejandra; Hernández-Rojas, Adriana C; Cerda-García-Rojas, Carlos M; Pereda-Miranda, Rogelio

    2011-08-05

    A protocol for stereochemical analysis, based on the systematic comparison between theoretical and experimental vicinal (1)H-(1)H NMR coupling constants, was developed and applied to a series of flexible compounds (1-8) derived from the 6-heptenyl-5,6-dihydro-2H-pyran-2-one framework. The method included a broad conformational search, followed by geometry optimization at the DFT B3LYP/DGDZVP level, calculation of the vibrational frequencies, thermochemical parameters, magnetic shielding tensors, and the total NMR spin-spin coupling constants. Three scaling factors, depending on the carbon atom hybridizations, were found for the (1)H-C-C-(1)H vicinal coupling constants: f((sp3)-(sp3)) = 0.910, f((sp3)-(sp2)) = 0.929, and f((sp2)-(sp2))= 0.977. A remarkable correlation between the theoretical (J(pre)) and experimental (1)H-(1)H NMR (J(exp)) coupling constants for spicigerolide (1), a cytotoxic natural product, and some of its synthetic stereoisomers (2-4) demonstrated the predictive value of this approach for the stereochemical assignment of highly flexible compounds containing multiple chiral centers. The stereochemistry of two natural 6-heptenyl-5,6-dihydro-2H-pyran-2-ones (14 and 15) containing diverse functional groups in the heptenyl side chain was also analyzed by application of this combined theoretical and experimental approach, confirming its reliability. Additionally, a geometrical analysis for the conformations of 1-8 revealed that weak hydrogen bonds substantially guide the conformational behavior of the tetraacyloxy-6-heptenyl-2H-pyran-2-ones.

  8. Study on the Chemical Compositions of Valeriana Jatamansi%蜘蛛香的化学成分研究

    Institute of Scientific and Technical Information of China (English)

    李元旦; 李蓉涛; 李海舟

    2011-01-01

    目的:对蜘蛛香根中的化学成分进行研究.方法:采用硅胶柱色谱,羟丙基葡萄糖凝胶柱层析Sephadex LH-20及HPLC(高效液相色谱)等分离纯化手段,从蜘蛛香(Valeriana jatamansi)根中分离出了17个化合物,通过理化性质和光谱数据分析.结果:分别被鉴定为(3S,4R,5S,7S,8S,9S)-3,8-epoxy-7-hydroxy-4,8-dimethylper-hydrocyclopenta[c]pyran(1),(3S,4S,5S,7S,8S,9S)-3,8-ethoxy-7-hydroxy-4,8-dimethylperhydrocyclopenta[c]pyran(2),4-β-hydroxy-8-β-methoxy-10-methylene-2,9-dioxatricyclo[4.3.1.03.7]decan(3),6-hydroxy-7-(hydroxymethyl)-4-methyl-enehexahydrocyclopenta[c]pyran-1-(3H)-one(4),jatamansi A(5),jatamansi G(6),8-hydroxypinoresinol(7),2,5-di(4-hydroxy-3-methoxyphenyl)-1,4-dioxan(8),pinoresinol(9),(+)-2-(3,4-dimethoxyphenyl)-6-(3,4-dihydroxyphenyl)-2,7-dioxabi-cyclo[3,3,0]octane(10),pinoresinol monomethyl ether(11),prinsepoil(12),(-)-massoniresinol(13),cinnamolide(14),valeriananoid A(15),valeriananoid C(16)和volvatrate A(17).结论:化合物3、4和17与化合物7~14为首次在该植物中发现.

  9. 12-(3,4,5-Trimethoxyphenyl-2,3,4,12-tetrahydro-1H-5-oxatetraphen-1-one: crystal structure and Hirshfeld surface analysis

    Directory of Open Access Journals (Sweden)

    Mukesh M. Jotani

    2016-06-01

    Full Text Available In the title compound, C26H24O5, the pyran ring has a flattened-boat conformation, with the 1,4-related ether O and methine C atoms lying 0.1205 (18 and 0.271 (2 Å, respectively, above the least-squares plane involving the doubly bonded C atoms (r.m.s deviation = 0.0208 Å. An envelope conformation is found for the cyclohexene ring, with the flap atom being the middle methylene C atom, lying 0.616 (2 Å out of the plane defined by the remaining atoms (r.m.s. deviation = 0.0173 Å. The fused four-ring system is approximately planar, with the dihedral angle between the least-squares planes through the cyclohexene and naphthyl rings being 10.78 (7°. The trisubstituted benzene ring occupies a position almost perpendicular to the pyran ring [dihedral angle = 83.97 (4°]. The most prominent feature of the packing is the formation of zigzag supramolecular chains mediated by aryl-C—H...O(methoxy interactions; chains are connected into a three-dimensional architecture by methylene- and methyl-C—H...π interactions. The prevalence of C—H...O and C—H...π interactions is confirmed by an analysis of the Hirshfeld surface. A comparison with related structures suggests that the molecular conformation of the title compound is relatively robust with respect to varying substitution patterns at the methine C atom of the pyran ring.

  10. Cascading radical cyclization of bis-vinyl ethers: mechanistic investigation reveals a 5-exo/3-exo/retro-3-exo/5-exo pathway.

    Science.gov (United States)

    O'Rourke, Natasha F; Davies, Katherine A; Wulff, Jeremy E

    2012-10-05

    We recently described an iterative synthesis of oligo-vinyl ethers, followed by a radical cascade to provide a family of hexahydro-2H-furo[3,4-b]pyrans. Our results for the radical cascade were consistent with either a direct 6-endo-trig addition of a vinyl radical onto the first vinyl ether function or an initial 5-exo-trig addition, followed by rearrangement to the more stable anomeric radical intermediate. In this report, we describe our further mechanistic studies aimed at distinguishing between these two possibilities and conclude that the 5-exo/3-exo/retro-3-exo pathway is dominant.

  11. Red Organic Light—Emitting Diodes Based on Energy Levels Matching of Dopant with the Host Materials

    Institute of Scientific and Technical Information of China (English)

    朱文清; 蒋雪茵; 张志林; 许少鸿

    2003-01-01

    By doping red dye 4-dicyanomethylene-2-(tert-butyl)-6-methyl-4H-pyran(DCJTB) in the tris-(8-hydroxyquinolinato) metal Mq3 (where M = AI, Ga, In) chelate complexes, a series of red-dopant organic light-emitting diodes with different doping concentra-tions have been fabricated. The electroluminescence efficiency of these red diodes with a DCJTB doped Mq3 emitting layer is found to be decreased markedly with the increasing of doping concentration. Electroluminescence characteristics of these devices are studied in terms of energy levels matching of red-dopant with the host materials and carrier transporting layers.

  12. Red Organic Light-Emitting Diodes Based on Energy Levels Matching of Dopant with the Host Materials%掺杂剂与基质材料能量匹配的红色有机发光二极管

    Institute of Scientific and Technical Information of China (English)

    朱文清; 蒋雪茵; 张志林; 许少鸿

    2003-01-01

    By doping red dye 4-dicyanomethylene-2-(tert-butyl)-6-methyl-4H-pyran(DCJTB) in the tris-(8-hydroxyquinolinato) metalMq3 (where M = Al, Ga, In) chelate complexes, a series of red-dopant organic light-emitting diodes with different doping concentra-tions have been fabricated. The electroluminescence efficiency of these red diodes with a DCJTB doped Mq3 emitting layer is found tobe decreased markedly with the increasing of doping concentration. Electroluminescence characteristics of these devices are studied interms of energy levels matching of red-dopant with the host materials and carrier transporting layers.

  13. Binary heterocyclic systems containing the ethylideneamino linkage: synthesis of some new heterocyclic compounds bearing the naphtho-[2,1-b]furan moiety

    Directory of Open Access Journals (Sweden)

    A. H. BEDAIR

    2006-05-01

    Full Text Available Ethylidene hydrazine (4a,b and thiazolidin-4-one (5 derivatives were synthesized by the reaction of ethylidenethiosemicarbazide derivative (3a with a-haloketone/ethyl bromoacetate, respectively. Hetrocyclization of ethylideneacetohydrazide derivative (7 with o-phenolic aldehydes gave the corresponding coumarin derivatives (8,9. The interaction of 7 with acetylacetone afforded the corresponding pyridine derivative (10. Treatment of the arylidene derivative 11b with malononitrile afforded the corresponding pyran derivative (12. The new products 3-12 were subjected to IR, 1H NMR and mass spectra studies.

  14. A new naphthoquinoneimine derivative from the marine algal-derived endophytic fungus Aspergillus niger EN-13

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Cultivation of an endophytic fungus Aspergillus niger EN-13 that was isolated from the inner tissue of the marine brown alga Colpomenia sinuosa resulted in the characterization of a new naphthoquinoneimine derivative, namely, 5,7-dihydroxy-2-[1-(4-methoxy-6-oxo-6H-pyran-2-yl)-2-phenylethylamino]-[ 1,4]naphthoquinone. The structure of the new compound was established on the basis of various NMR spectroscopic analyses including 2D NMR techniques, EI-MS, and HR-ESI-MS. This compound displayed moderate antifungal activity.

  15. A versatile route to benzodiazocine and spiropyran derivatives through chalcones

    Indian Academy of Sciences (India)

    Johnson George; Saurabh Singh; Rahul Joshi; Ramchand T Pardasani

    2013-05-01

    Syntheses of 3-(phenyl)-benzo[b]thiophene [2, 3-d][1,2] benzodiazocine derivatives have been accomplished by the reaction of 3-phenacylidine-2-benzo[b]thiophene-2-ones with o-phenylene diamine. The photolytic reaction with trans-stilbene resulted in the exclusive formation of spiro{2',5',6'-triphenyl-2H-pyran-4',3}-benzo[b]thiophene-2-one derivatives. Theoretical calculations have been performed to study the mechanism and stereoselectivity of products. Good yield and broad scope of usable substrates of industrial relevance are other prominent features of the present methodologies.

  16. 3,3-Dimethyl-cis-9a,13a-diphenyl-2,3,9a,11,12,13a-hexahydro-1H-benzo[h][1,4]dioxino[2′,3′:5,6][1,4]dioxino[2,3-f]chromene

    Directory of Open Access Journals (Sweden)

    Bauer O. Bernardes

    2013-09-01

    Full Text Available In the title dihydrodioxin, C31H28O5, the dioxane ring has a chair conformation, whereas each of the pyran and dioxine rings has an envelope conformation with methylene and quaternary C atoms, respectively, being the flap atoms. The phenyl rings are cis and form a dihedral angle of 82.11 (10°. The molecular structure is stabilized by C—H...O contacts. In the crystal packing, supramolecular layers parallel to (101 are sustained by C—H...π interactions.

  17. 3-Amino-1-phenyl-1H-benzo[f]chromene-2-carbonitrile

    Directory of Open Access Journals (Sweden)

    Sabry H. H. Younes

    2013-03-01

    Full Text Available In the title compound, C20H14N2O, the phenyl ring is almost normal to the naphthalene ring system with a dihedral angle of 86.72 (9°. The 4H-pyran ring fused with the naphthalene ring system has a boat conformation. In the crystal, molecules are linked into a helical supramolecular chain along the b axis via N—H...N hydrogen bonds. The chains are consolidated into a three-dimensional architecture by C—H...π interactions.

  18. 1-(5-Hydroxy-2,2,8,8-tetramethyl-2H,8H-pyrano[2,3-f]chromen-6-yl-3-(4-methoxyphenylprop-2-en-1-one

    Directory of Open Access Journals (Sweden)

    Sunayna Pawar

    2013-04-01

    Full Text Available In the biologically active title compound, C26H26O5, the pyran ring of the chromene unit adopts a half-chair conformation. The C=C double bond of the propenone unit exhibits a trans conformation and the carbonyl group is syn conformation to the double bond. The dihedral angle between the benzene ring and the benzopyranone moiety is 31.54 (4°. The molecular structure is stabilized by an intramolecular C=O...H—O hydrogen bond.

  19. 2-Amino-4-(2-chlorophenyl-5-oxo-5,6,7,8-tetrahydro-4H-chromene-3-carbonitrile ethanol monosolvate

    Directory of Open Access Journals (Sweden)

    Yan Qiao

    2011-11-01

    Full Text Available In the title compound, C16H13ClN2O2·C2H6O, the fused cyclohexene and pyran rings adopt envelope and flattened boat conformations, respectively. In the crystal, N—H...O and O—H...O hydrogen bonds link the chromene and ethanol solvent molecules into infinite chains along the c axis, and N—H...N hydrogen bonds link these chains into a three-dimensional framework. Weak C—H...π interactions are also present.

  20. (4R,7S-2-Amino-4-(3,4-dimethoxyphenyl-5-oxo-7-phenyl-5,6,7,8-tetrahydro-4H-chromene-3-carbonitrile monohydrate

    Directory of Open Access Journals (Sweden)

    Rong Sun

    2012-02-01

    Full Text Available The title compound, C24H22N2O4·H2O, was obtained by the reaction of 3,4-dimethoxybenzaldehyde, malononitrile and 5-phenylcyclohexane-1,3-dione. The cyclohexyl and pyran rings show half-boat and V-shaped conformations, respectively. The dihedral angle between the phenyl and benzene ring planes is 30.67 (9°. The organic molecules are packed in a two-dimensional network parallel to the bc plane stabilized by intermolecular N—H...N and N—H...O hydrogen bonds.

  1. Lewis acid-promoted cyclization reactions of alkenyl ethenetricarboxylates: stereoselective synthesis of 2-oxotetrahydrofurans and 2-oxopyrrolidines.

    Science.gov (United States)

    Yamazaki, Shoko; Fujinami, Ken; Maitoko, Yuki; Ueda, Khota; Kakiuchi, Kiyomi

    2013-09-06

    Lewis acid-promoted intramolecular reactions of alkenyl ethenetricarboxylates and the corresponding amides have been examined. Reaction of allyl ethenetricarboxylates and the amides with Lewis acids (1-2 equiv) such as TiCl4, TiBr4, AlCl3, and AlBr3 gave 3,4-trans-halogenomethyl 2-oxotetrahydrofuran and pyrrolidine derivatives stereoselectively in high yields. The stereochemistries were determined by NOE experiments. Reaction of alkyl-substituted allylic ethenetricarboxylates with Lewis acids gave chloro 2-oxotetrahydrofurans and pyrans. For some alkyl-substituted substrates, cationic intermediates may be formed under the reaction conditions, and rearranged products have been obtained.

  2. 2-Acetylamino-1,3,4,6-tetra-O-(trimethylsilyl-2-deoxy-α-d-glucopyranose

    Directory of Open Access Journals (Sweden)

    Zhao-Dong Cheng

    2013-06-01

    Full Text Available The title compound, C20H47NO6Si4, was synthesized by per-O-trimethylsilylation of N-acetyl-d-glucosamine using chlorotrimethylsilane in the presence of hexamethyldisiloxane. The trimethylsilyl group and acetamido group are located on the same side of the pyran ring, showing an α-configuration glycoside. One of the trimethylsilyl groups is disordered over two orientations, with site-occupancy factors of 0.625 (9 and 0.375 (9. In the crystal, N—H...O hydrogen bonds link the molecules into supramolecular chains along the a-axis direction.

  3. (2-Oxo-2H-benzo[h]chromen-4-ylmethyl morpholine-4-carbodithioate

    Directory of Open Access Journals (Sweden)

    Rajni Kant

    2012-04-01

    Full Text Available In the title compound, C19H17NO3S2, the morpholine ring is in a chair conformation. In the coumarin ring system, the dihedral angle between the benzene and pyran rings is 3.9 (1°. In the crystal, weak C—H...O interactions link the molecules into corrugated layers parallel to (102. The crystal packing also exhibits π–π interactions, with distances of 3.644 (1 and 3.677 (1 Å between the centroids of the benzene rings of neighbouring molecules.

  4. Iodine - catalyzed prins cyclization of aliphatic and aromatic ketones

    Energy Technology Data Exchange (ETDEWEB)

    Kishore, K.R.; Reddy, K.; Silva Junior, Luiz F., E-mail: luizfsjr@iq.usp.br [Universidade de Sao Paulo (IQ/USP), SP (Brazil). Inst. de Quimica. Dept. de Quimica Fundamental

    2013-09-15

    Iodine-catalyzed Prins cyclization of homoallylic alcohols and ketones was investigated. Anhydrous conditions and inert atmosphere are not required in this metal-free protocol. The reaction of 2-(3,4-dihydronaphthalene-1-yl)propan-1-ol with six aliphatic symmetric ketones gave the desired products in 67-77% yield. Cyclization was performed with four aliphatic unsymmetric ketones, leading to corresponding pyrans in 66-76% yield. Prins cyclization was also accomplished with four aromatic ketones in 37-66% yield. Finally, Prins cyclization of the monoterpene isopulegol and acetone was successfully achieved. (author)

  5. Synthesis, Reactions and Evaluation of the Antimicrobial Activity of Some 4-(p-Halophenyl-4H-naphthopyran, Pyranopyrimidine and Pyranotriazolopyrimidine Derivatives

    Directory of Open Access Journals (Sweden)

    Ashraf H. F. Abd El-Wahab

    2012-07-01

    Full Text Available A series of naphthopyran derivatives 3a–f were prepared. Reaction of 2-amino-4-(p-chlorophenyl-7-methoxy-4H-naphtho[2,1-b]pyran-3-carbonitrile (3b with Ac2O afforded two products, 2-acetylamino-7-methoxy-4-(p-chlorophenyl-4H-naphtho-[2,1-b]pyran-3-carbonitrile (4 and 10,11-dihydro-3-methoxy-9-methyl-12-(p-chloro-phenyl-12H-naphtho[2,1-b]pyran[2,3-d]pyrimidine-11-one (5 and treatment of 3b with benzoyl chloride gave the pyranopyrimidin-11-one derivative 6. While treatment of 3b with formamide afforded 11-amino-3-methoxy-12-(p-chlorophenyl-12H-naphtho[2,1-b]pyrano[2,3-d]pyrimidine (7. Reaction of 3b with triethyl orthoformate gave the corresponding 2-ethoxymethyleneamino-7-methoxy-4-(p-chlorophenyl-4H-naphtho-[2,1-b]pyran-3-carbonitrile (8. Hydrazinolysis of 8 in EtOH at room temperature yielded 10-amino-10,11-dihydro-11-imino-3-methoxy-12-(p-chlorophenyl-12H-naphtho[2,1-b]pyrano-[2,3-d]pyrimidine (9, while aminolysis of 8 with methylamine or dimethylamine gave the corresponding pyranopyrimidine and N,N-dimethylaminomethylene derivatives 10 and 11. Condensation of 9 with some carboxylic acid derivatives afforded triazolopyrimidine derivatives 12–16, while reaction of 9 with benzaldehyde gave 10-benzalamino-10,11-dihydro-11-imino-3-methoxy-12-(p-chlorophenyl12H-naphtho[2,1-b]pyrano[2,3-d]pyrimidine (17. The structures of the newly synthesized compounds were confirmed by spectral data. The

  6. Synthesis of (±)-8-deisopropyladunctin B.

    Science.gov (United States)

    Nomura, Sayo; Arimitsu, Kenji; Yamaguchi, Satoshi; Kosuga, Yuya; Kakimoto, Yuko; Komai, Takanori; Hasegawa, Kazumasa; Nakanishi, Akira; Miyoshi, Tamami; Iwasaki, Hiroki; Ozeki, Minoru; Kawasaki, Ikuo; Kurume, Ai; Ohta, Shunsaku; Yamashita, Masayuki

    2012-01-01

    (±)-8-Deisopropyladunctin B, the deisopropyl form of adunctin B, which was isolated from the leaves of Piper aduncum (Piperaceae) collected in Papua New Guinea, was synthesized in 0.77% overall yield in 17 steps from 5,7-dimethoxycoumarin-3-carboxylate. The key step was our original stereoconvergent skeleton transformation from 1,2,2a,8b-tetrahydro-3H-benzo[b]cyclobuta[d]pyran-3-one to 1,2,4a,9b-tetrahydrodibenzofuran-4-ol with dimethylsulfoxonium methylide.

  7. Conversion of 3-Carbethoxy-4-methyl Coumarin Derivatives into Several New Annelated Coumarin Derivatives

    Institute of Scientific and Technical Information of China (English)

    BAKEER; HadeerMohammed

    2003-01-01

    The reaction of ethyl esters of 4-methyl-2-oxo-2H-l-benzo(naphtho) pyran.3-carboxylic acids (1) with aromatic aldehy-des in the presence of piperidine yielded 4-styryl-3-carboxami-dopiperidyl connmrin derivatives 4. The reaction of hydrazlne hydrate with 1 gave acetophenone hydrozone derivatives 5 and acetophenone azine derivatives 6. The reaction of 1 with prima-ry amines afforded compomlds 7—9. And the treatment of la with Grignard reagents afforded 3-aroyl-4-methyl coumarin derivatives 10.

  8. Nano-titania-supported Preyssler-type heteropolyacid: An efficient and reusable catalyst in ultrasound-promoted synthesis of 4-chromenes and 4-pyrano[2,3-c]pyrazoles

    Indian Academy of Sciences (India)

    Davood Azarifar; Seyed-Mola Khatami; Razieh Nejat-Yami

    2014-01-01

    An efficient and convenient procedure has been described for one-pot multi-component synthesis of tetrahydrobenzo[b]pyrans known as 4-chromenes and 1,4-dihydropyrano[2,3-c]pyrazole derivatives in the presence of nano-titania-supported Preyssler-type heteropolyacid, n-TiO2/H14[NaP5W30O110], as a heterogeneous catalyst. The reactions proceeded smoothly under ultrasound irradiation condition to afford the corresponding products in quantitative yields. The catalyst can be easily recovered and reused for several successive fresh runs with no significant loss of catalytic activity.

  9. Dye alignment in luminescent solar concentrators: II. Horizontal alignment for energy harvesting in linear polarizers.

    Science.gov (United States)

    Mulder, C L; Reusswig, P D; Beyler, A P; Kim, H; Rotschild, C; Baldo, M A

    2010-04-26

    We describe Linearly Polarized Luminescent Solar Concentrators (LP-LSCs) to replace conventional, purely absorptive, linear polarizers in energy harvesting applications. As a proof of concept, we align 3-(2-Benzothiazolyl)-N,N-diethylumbelliferylamine (Coumarin 6) and 4-dicyanomethyl-6-dimethylaminostiryl-4H-pyran (DCM) dye molecules linearly in the plane of the substrate using a polymerizable liquid crystal host. We show that up to 38% of the photons polarized on the long axis of the dye molecules can be coupled to the edge of the device for an LP-LSC based on Coumarin 6 with an order parameter of 0.52.

  10. Enantioselctive Syntheses of Sulfur Analogues of Flavan-3-Ols

    Directory of Open Access Journals (Sweden)

    Richard Lombardy

    2010-08-01

    Full Text Available The first enantioselective syntheses of sulfur flavan-3-ol analogues 1–8 have been accomplished, whereby the oxygen atom of the pyran ring has been replaced by a sulfur atom. The key steps were: (a Pd(0 catalyzed introduction of –S t-butyl group, (b Sharpless enantioselective dihydroxylation of the alkene, (c acid catalyzed ring closure to produce the thiopyran ring, and (d removal of benzyl groups using N,N-dimethylaniline and AlCl3. The compounds were isolated in high chemical and optical purity.

  11. Fullerene-Based Macro-Heterocycle Prepared through Selective Incorporation of Three N and Two O Atoms into C60.

    Science.gov (United States)

    Li, Yanbang; Zhang, Gaihong; Wang, Dian; Xu, Beidi; Xu, Dan; Lou, Ning; Gan, Liangbing

    2016-11-14

    A 14-membered heterocycle is created on the C60 cage skeleton through a multistep procedure. Key steps involve repeated PCl5 -induced hydroxylamino N-O bond cleavage leading to insertion of nitrogen atoms, and also piperidine-induced peroxo O-O bond cleavage leading to insertion of oxygen atoms. The hetero atoms form one pyrrole, two pyran, and one diazepine rings in conjunction with the C60 skeleton carbon atoms. The fullerene-based macrocycle showed unique reactivities towards fluoride ion and copper salts. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Piperidine-mediated synthesis of thiazolyl chalcones and their derivatives as potent antimicrobial agents.

    Science.gov (United States)

    Venkatesan, P; Maruthavanan, T

    2012-01-01

    A series of new thiazolyl chalcones, 1-[2-amino-4-methyl-1,3-thiazol-5-yl]-3-aryl-prop-2-en-1-one were prepared by piperidine mediated Claisen-Schmidt condensation of thiazolyl ketone with aromatic aldehyde. These chalcones on cyclisation gave 2-amino-6-(2-amino-4-methyl-1,3-thiazol-5-yl)-4-aryl-4H-pyridine-3-carbonitrile and 2-amino-6-(2-amino-4-methyl-1,3-thiazol-5-yl)-4-aryl-4H-pyran-3-carbonitrile. The result showed that the compounds exhibited marked potency as antimicrobial agents.

  13. Methyl N-{4-[(4-methoxyphenoxymethyl]-2-oxo-2H-chromen-7-yl}carbamate

    Directory of Open Access Journals (Sweden)

    K. Mahesh Kumar

    2012-06-01

    Full Text Available In the title compound, C19H17NO6, the dihedral angle between the 2H-chromene ring system and benzene ring is 5.34 (6°. A short intramolecular C—H...O contact occurs. In the crystal, molecules are linked by N—H...O hydrogen bonds, generating C(8 chains propagating in [010]. The chains are linked by C—H...O interactions and the packing also exhibits π–π stacking interactions between benzene and pyran rings, with a centroid–centroid distance of 3.676 (9 Å.

  14. Unexpected Formation of Highly Functionalized Dihydropyrans via Addition-Cyclization Reactions Between Dimethyl Oxoglutaconate and α,β-Unsaturated Hydrazones.

    Science.gov (United States)

    Mullins, Jason E; Etoga, Jean-Louis G; Gajewski, Mariusz; Degraw, Joseph I; Thompson, Charles M

    2009-05-20

    The condensation between dienophiles and α,β-unsaturated hydrazone azadienes was previously reported to afford piperidines. During an attempt to adapt this reaction to the preparation of piperidine-based conformationally-restricted analogs of glutamate, it was discovered that the electrophile, dimethyl oxoglutaconate (DOG) led to highly substituted dihydropyrans in 20-50% yield. The unexpected pyran product likely results from an initial 1,4-addition of the hydrazone to the oxoglutaconate followed by intramolecular cyclization of the resultant enolate oxygen to the α,β-unsaturated iminium ion. Further manipulations afford substituted tetrahydropyran 6-methamino-2,4-dicarboxylic acids.

  15. Synthesis and functionalization of bicyclic N,O-acetal scaffolds from furfural.

    Science.gov (United States)

    van der Pijl, Ferdi; van Delft, Floris L; Rutjes, Floris P J T

    2015-06-01

    We have synthesized biologically relevant 6-aza-8-oxa[3.2.1]bicyclooctane scaffolds in a five-step procedure starting from furfural. Besides showing that these scaffolds are amenable to decoration via standard functional group interconversions, we also describe investigations for further functionalization via Lewis acid-mediated N,O-acetal opening, followed by nucleophilic trapping of the resulting intermediate cation. By using different nucleophiles, we have successfully prepared a modest library of 2,6-trans-disubstituted pyrans in good yields and in a highly diastereoselective manner.

  16. 6-Fluoro-4-oxo-4H-chromene-3-carbaldehyde

    Directory of Open Access Journals (Sweden)

    Yoshinobu Ishikawa

    2014-05-01

    Full Text Available In the title compound, C10H5FO3, the non-H atoms are essentially coplanar (r.m.s. deviation = 0.0071 Å, with the largest deviation from the mean plane [0.0203 (15 Å] being found for the ring C atom in the 2-position. In the crystal, molecules are linked into a three-dimensional architecture via C—H...O hydrogen bonds and π–π stacking interactions between the chromone units along the a-axis direction [centroid–centroid distance between the benzene and pyran rings = 3.707 (2 Å].

  17. Synthesis and Antibacterial Evaluation of Novel Heterocyclic Compounds Containing a Sulfonamido Moiety

    Directory of Open Access Journals (Sweden)

    Eman A. El-Bordany

    2013-01-01

    Full Text Available Aiming for the synthesis of new heterocyclic compounds containing a sulfonamido moiety suitable for use as antibacterial agents, the precursor ethyl {[4-N-(4,6-dimethylpyrimidin-2-ylsulfamoyl]phenylazo}cyanoacetate was reacted with a variety of active methylene compounds producing pyran, pyridine and pyridazine derivatives. Also, the reactivity of the precursor hydrazone towards hydrazine derivatives to give pyrazole and oxazole derivatives was studied. On the other hand, treatment of the same precursor with urea, thiourea and/or guanidine hydrochloride furnished pyrimidine and thiazine derivatives, respectively. The newly synthesized compounds were tested for antibacterial activity, whereby eight compounds were found to have high activities.

  18. Two New Iridoids from Verbena officinalis L.

    Directory of Open Access Journals (Sweden)

    Jicheng Shu

    2014-07-01

    Full Text Available Two new iridoids, 3-(5-(methoxycarbonyl-2-oxo-2H-pyran-3-ylbutanoic acid, named verbeofflin I (1, and 7-hydroxydehydrohastatoside (2, were isolated from the aerial part of Verbena officinalis L, along with three known iridoids, verbenalin (3, 3,4-dihydroverbenalin (4, hastatoside (5 by means of various column chromatography steps. The structures of these compounds were elucidated through analysis of their spectroscopic data obtained using 1D and 2D NMR and MS techniques. Verbeofflin I (1 is the new class of secoiridoid in the family Verbenaceae.

  19. 6-Chloro-4-oxo-4H-chromene-3-carb-aldehyde.

    Science.gov (United States)

    Ishikawa, Yoshinobu

    2014-05-01

    In the title compound, C10H5ClO3, a chlorinated 3-formyl-chromone derivative, the non-H atoms are essentially coplanar (r.m.s. deviation = 0.0456 Å) with the largest deviation from the least-squares plane [0.1136 (16) Å] being found for the ring-bound carbonyl O atom. In the crystal, mol-ecules are linked through stacking inter-actions along the b axis [shortest centroid-centroid distance between the pyran and benzene rings = 3.4959 (15) Å].

  20. Diversity-Oriented Synthesis of a Library of Substituted Tetrahydropyrones Using Oxidative Carbon-Hydrogen Bond Activation and Click Chemistry

    Directory of Open Access Journals (Sweden)

    Paul E. Floreancig

    2011-05-01

    Full Text Available Eighteen (2RS,6RS-2-(4-methoxyphenyl-6-(substituted ethyldihydro-2H-pyran-4(3Hones were synthesized via a DDQ-mediated oxidative carbon-hydrogen bond activation reaction. Fourteen of these tetrahydropyrans were substituted with triazoles readily assembled via azide-alkyne click-chemistry reactions. Examples of a linked benzotriazole and pyrazole motif were also prepared. To complement the structural diversity, the alcohol substrates were obtained from stereoselective reductions of the tetrahydropyrone. This library provides rapid access to structurally diverse non-natural compounds to be screened against a variety of biological targets.

  1. Occurrence of urolithins, gut microbiota ellagic acid metabolites and proliferation markers expression response in the human prostate gland upon consumption of walnuts and pomegranate juice.

    Science.gov (United States)

    González-Sarrías, Antonio; Giménez-Bastida, Juan A; García-Conesa, María T; Gómez-Sánchez, María B; García-Talavera, Noelia V; Gil-Izquierdo, Angel; Sánchez-Alvarez, Carmen; Fontana-Compiano, Luis O; Morga-Egea, Juan P; Pastor-Quirante, Francisco A; Martínez-Díaz, Francisco; Tomás-Barberán, Francisco A; Espín, Juan Carlos

    2010-03-01

    Epidemiology supports the important role of nutrition in prostate cancer (PCa) prevention. Pomegranate juice (PJ) exerts protective effects against PCa, mainly attributed to PJ ellagitannins (ETs). Our aim was to assess whether ETs or their metabolites ellagic acid and urolithins reach the human prostate upon consumption of ET-rich foods and to evaluate the effect on the expression of three proliferation biomarkers. Sixty-three patients with BPH or PCa were divided into controls and consumers of walnuts (35 g walnuts/day) or pomegranate (200 mL PJ/day) for 3 days before surgery. Independently of the ETs source, the main metabolite detected was urolithin A glucuronide, (3,8-dihydroxy-6H-dibenzo[b,d]pyran-6-one glucuronide) (up to 2 ng/g) together with the traces of urolithin B glucuronide, (3-hydroxy-6H-dibenzo[b,d]pyran-6-one glucuronide) and dimethyl ellagic acid. The small number of prostates containing metabolites was likely caused by clearance of the compounds during the fasting. This was corroborated in a parallel rat study and thus the presence of higher quantities of metabolites at earlier time points cannot be discarded. No apparent changes in the expression of CDKN1A, MKi-67 or c-Myc were found after consumption of the walnuts or PJ. Our results suggest that urolithin glucuronides and dimethyl ellagic acid may be the molecules responsible for the beneficial effects of PJ against PCa.

  2. 2-Chloro-8,8-dimethyl-8,9-dihydro-7H-chromeno[2,3-b]quinoline-10,12-dione

    Directory of Open Access Journals (Sweden)

    Thothadri Srinivasan

    2013-02-01

    Full Text Available The asymmetric unit of the title compound, C18H14ClNO3, contains two independent molecules (A and B. In both molecules, the cyclohexanone ring has a chair conformation. The dihedral angles between the pyran ring and the pyridine and chlorophenyl rings are 2.13 (9 and 2.19 (9°, respectively, in A, and 0.82 (9 and 1.93 (9°, respectively, in B. The carbonyl O atoms deviate from the pyran and benzene rings to which they are attached by −0.092 (2 and 0.064 (2 Å, respectively, in A, and by −0.080 (2 and −0.063 (2 Å, respectively, in B. In the crystal, the A molecules are linked via C—H...O hydrogen bonds, forming double-stranded chains along [100]. They lie parallel to the double-stranded chains formed by the B molecules, which are also linked via C—H...O hydrogen bonds. The chains stack up the c axis in an –A–A–B–B–A–A– manner, with a number of π–π interactions involving A and B molecules; the centroid–centroid distances vary from 3.4862 (11 to 3.6848 (11 Å

  3. Solvent-dependent fluorescence enhancement and piezochromism of a carbazole-substituted naphthopyran

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Lihui; Wang, Aixia [Faculty of Chemistry, Northeast Normal University, Changchun 130024 (China); Wang, Guang, E-mail: wangg923@nenu.edu.cn [Faculty of Chemistry, Northeast Normal University, Changchun 130024 (China); Munyentwari, Alexis [Faculty of Chemistry, Northeast Normal University, Changchun 130024 (China); Zhou, Yihan, E-mail: yhzhou@ciac.ac.cn [National Analytical Research Center of Electrochemistry and Spectroscopy, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China)

    2015-09-15

    A novel carbazole-substituted naphthopyran, 3,3-bis-(4-carbazolylphenyl)-[3H]-naphtho[2,1-b]pyran (CzNP) was designed and synthesized. The new compound exhibited normal photochromism in dichloromethane solution and the UV irradiation did not influence its fluorescence. On the contrary, the fluorescence of CzNP in N,N-dimethylformamide (DMF) was intensively enhanced to 29 times after 60 min of the UV irradiation and this enhanced fluorescence can be quenched by addition of triethylamine (TEA). The study of enhanced extent of fluorescence of CzNP in solvents with different polarities and in mixed solvents demonstrated that the enhanced fluorescence is dependent on the polarity of solvents. The larger the polarity of solvent was, the stronger was the fluorescence of CzNP. CzNP also exhibited piezochromic performance and the pressure led to the cleavage of the C–O bond of pyran ring. - Highlights: • A carbazole-substituted photochromic naphthopyran was designed and synthesized. • The fluorescence was enhanced under the existence of DMF and UV irradiation. • The polarity of solvent was the dominating factor to affect the fluorescence. • The new compound also displayed piezochromic performance.

  4. Crystal structure of canagliflozin hemihydrate.

    Science.gov (United States)

    Liu, Kai-Hang; Gu, Jian-Ming; Hu, Xiu-Rong; Tang, Gu-Ping

    2016-05-01

    There are two canagliflozin mol-ecules (A and B) and one water mol-ecule in the asymmetric unit of the title compound, C24H25FO5S·0.5H2O [systematic name: (2S,3R,4R,5S,6R)-2-(3-{[5-(4-fluoro-phen-yl)thio-phen-2-yl]meth-yl}-4-methylphen-yl)-6-(hy-droxy-meth-yl)-3,4,5,6-tetra-hydro-2H-pyran-3,4,5-triol hemihydrate]. The dihedral angles between the methyl-benzene and thio-phene rings are 115.7 (4) and 111.7 (4)°, while the dihedral angles between the fluoro-benzene and thio-phene rings are 24.2 (6) and 20.5 (9)° in mol-ecules A and B, respectively. The hydro-pyran ring exhibits a chair conformation in both canagliflozin mol-ecules. In the crystal, the canagliflozin mol-ecules and lattice water mol-ecules are connected via O-H⋯O hydrogen bonds into a three-dimensional supra-molecular architecture.

  5. 3′-[Hydroxy(4-oxo-4H-chromen-3-ylmethyl]-2-oxospiro[indoline-3,2′-pyrrolidine]-3′-carbonitrile

    Directory of Open Access Journals (Sweden)

    E. Govindan

    2012-01-01

    Full Text Available In the title compound, C23H19N3O4, the pyran ring adopts a half-chair conformation, while the pyrrolidine (with a C atom as the flap atom and the five-membered ring in the indoline (with a C atom as the flap atom ring system adopt slight envelope conformations. The pyrrolidine ring makes dihedral angles of 83.3 (1 and 60.4 (1° with the mean plane through all non-H atoms of the indoline and chromene ring systems, respectively. In the crystal, molecules are connected by two unique N—H...O and O—H...O hydrogen-bonding interactions, which form centrosymmetric patterns described by graph-set motifs R22(18 and R22(14. These two motifs combine to form a hydrogen-bonded chain which propagates in the a-axis direction. The crystal structure is also stablized by C—H...O interactions and by aromatic π–π stacking interactions between the pyran and benzene rings of neighbouring molecules [centroid–centroid distance = 3.755 (1 Å and slippage = 1.371 (2 Å].

  6. 2-Amino-4-(4-chlorophenyl-7,7-dimethyl-5-oxo-5,6,7,8-tetrahydro-4H-chromene-3-carbonitrile propan-2-one monosolvate

    Directory of Open Access Journals (Sweden)

    Shaaban K. Mohamed

    2012-06-01

    Full Text Available In the title compound, C18H17ClN2O2·C3H6O, the 4H-pyran ring is nearly planar [maximum deviation = −0.108 (1 Å] and the cyclohexene ring is puckered [puckering parameters QT = 0.4596 (17 Å, θ = 55.9 (2° and ϕ = 226.5 (3°]. The 4H-pyran ring is approximately perpendicular to the benzene ring [dihedral angle = 84.35 (7°] and is almost coplanar with the mean plane of the cyclohexene ring [dihedral angle = 8.64 (7°]. In the crystal, inversion-related main molecules are linked into dimers by pairs of N—H...N hydrogen bonds, generating an R22(12 graph-set motif. These dimers are further connected by N—H...O and C—H...N hydrogen bonds, forming a layer structure extending parallel to the (011 plane. In addition, the molecules within the layers interact with each other via C—H...π interactions.

  7. Crystal structure of 4-(4-methoxyphenyl-7,7-dimethyl-2-methylamino-3-nitro-7,8-dihydro-4H-chromen-5(6H-one

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    S. Antony Inglebert

    2014-09-01

    Full Text Available In the title compound, C19H22N2O5, the six-membered carbocyclic ring of the chromene moiety adopts an envelope conformation with the dimethyl-substituted C atom as the flap. The pyran ring has a flat-boat conformation. The methoxyphenyl ring is orthogonal to the mean plane of the chromene moiety, with a dihedral angle of 89.97 (8°. The amine N atom deviates from the chromene mean plane by 0.1897 (16 Å. The methylamine and the nitro group are involved in an intramolecular N—H...O hydrogen bond which generates an S(6 ring motif. They are slightly twisted out of the plane of the chromene moiety with torsion angles of C—N—C—O(pyran = 2.2 (3° and O(nitro—N—C—C = −5.6 (2°. In the crystal, there are only C—H...π interactions present, forming inversion-related dimers.

  8. New constituents from the trunk bark of Tabebuia heptaphylla; Novos constituintes quimicos das cascas do caule de Tabebuia heptaphylla

    Energy Technology Data Exchange (ETDEWEB)

    Garcez, Fernanda Rodrigues; Garcez, Walmir Silva; Mahmoud, Talal Suleiman; Figueiredo, Patricia de Oliveira [Universidade Federal de Mato Grosso do Sul (UFMS), Campo Grande, MS (Brazil). Dept. de Quimica]. E-mail: frgarcez@nin.ufms.br; Resende, Ubirazilda Maria [Universidade Federal de Mato Grosso do Sul (UFMS), Campo Grande, MS (Brazil). Dept. de Biologia

    2007-07-01

    A new triterpene, 3beta,6beta,21beta-trihydroxyolean-12-ene and a new iridoid, 8alpha-methyl-8beta-hydroxy-6beta-(3',4'-dimethoxy)benzoyloxy-1alpha, 3alpha-dimethoxy-octahydro-cyclopenta[c]pyran were isolated from the trunk bark of a specimen of Tabebuia heptaphylla (Bignoniaceae) collected in the 'Pantanal' of Mato Grosso do Sul, Brazil. Twelve known compounds were also obtained in this work, comprising four iridoids, 6-O-p-hydroxybenzoylajugol, 6-O-p-methoxybenzoylajugol, 6-O-3{sup ,}4{sup -}dimethoxybenzoylajugol, 8alpha-methyl-8beta-hydroxy-6beta-(4'-hydroxy)benzoyloxy-1alpha, 3alpha-dimethoxy-octahydro-cyclopenta[c]pyran, a cyclopentene dialdehyde, 2-formyl-5-(3',4'-dimethoxybenzoyloxy) -3-methyl-2-cyclopentene-1-acetaldehyde, a phenylethanoid glycoside, verbascoside and three benzoic acid derivatives, p-hydroxybenzoic, pmethoxybenzoic and 3,4-dimethoxybenzoic acids, in addition to squalene, sitostenone and sitosterol. The antioxidant properties of the isolated compounds were also evaluated in this work. (author)

  9. Crystal structure of 4-oxo-4H-chromene-3-carboxylic acid

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    Yoshinobu Ishikawa

    2015-08-01

    Full Text Available In the title compound, C10H6O4, also known as 3-carboxychromone, the non-H atoms of the chromone ring are essentially coplanar (r.m.s. deviation = 0.0057 Å, with the maximum deviation from their least-squares plane [0.011 (2 Å] being for a pyran C atom. The dihedral angle between the fused ring and plane of the carboxy group is 3.06 (2°. An intramolecular hydrogen bond is formed between the ring carbonyl O atom and the carboxy O—H atom, closing an S(6 loop. In the crystal, molecules are assembled by stacking interactions [centroid–centroid distance between the benzene and pyran rings = 3.844 (3 Å] and C—H...O hydrogen bonds, generating a three-dimensional network. Short contacts are also observed between the carboxy O and C atoms [C=O...C=O = 3.002 (3 Å].

  10. Three isoflavanones with cannabinoid-like moieties from Desmodium canum.

    Science.gov (United States)

    Botta, B; Gacs-Baitz, E; Vinciguerra, V; Delle Monache, G

    2003-09-01

    Three further derivatives of 5,7,2',4'-tetrahydroxy-6-methyl isoflavanone have been isolated from the root extract of Desmodium canum and assigned the structures 2,3-dihydro-5,7-dihydroxy-6-methyl-3-(1a,2,3,3a,8b,8c-hexahydro-6-hydroxy-1,1,3a-trimethyl-1H-4-oxabenzo[f]cyclobut[c,d]inden-7-yl)-4H-1-benzopyran-4-one (1) 2,3-dihydro-5,7-dihydroxy-6-methyl-3-(6a,7,8,10a-tetrahydro-3-hydroxy-6,6,9-trimethyl-6H-dibenzo[b,d]pyran-2-yl)-4H-1-benzopyran-4-one (2) 2,3-dihydro-5,7-dihydroxy-6-methyl-3-(3-hydroxy-6,6,9-trimethyl-6H-dibenzo[b,d]pyran-2-yl) 4H-1-benzopyran-4-one (3). The three compounds and the previously isolated chromene 4 all derive from the geranylated precursor 5 by a series of cannabinoid-like oxidative rearrangements.

  11. Identification of New Lactone Derivatives Isolated from Trichoderma sp., An Endophytic Fungus of Brotowali (Tinaspora crispa

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    Elfita

    2014-03-01

    Full Text Available Endophytic fungi is a rich source of novel organic compounds with interesting biological activities and a high level of structural diversity. As a part of our systematic search for new bioactive lead structures and specific profiles from endophytic fungi, an endophytic fungus was isolated from roots of brotowali (Tinaspora crispa, an important medicinal plant. Colonial morphological trait and microscopic observation revealed that the endophytic fungus was Trichoderma sp. The pure fungal strain was cultivated on 7 L Potatos Dextose Broth (PDB medium under room temperature (no shaking for 8 weeks. The ethyl acetate were added to cultur medium and left overnight to stop cell growth. The culture filtrates were collected and extracted with EtOAc and then taken to evaporation. Two new lactone derivatives, 5-hydroxy-4-hydroxymethyl-2H-pyran-2-one (1 and (5-hydroxy-2-oxo-2H pyran-4-yl methyl acetate (2 were obtained from the EtOAc extracts of Trichoderma sp. Their structures were determined on the basic of spectroscopic methods including UV, IR, 1H-NMR, 13C-NMR, HMQC, and HMBC.

  12. Ethyl 6-amino-5-cyano-4-phenyl-2,4-dihydropyrano[2,3-c]pyrazole-3-carboxylate dimethyl sulfoxide monosolvate

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    Naresh Sharma

    2014-07-01

    Full Text Available In the asymmetric unit of the title compound, C16H14N4O3·C2H6OS, there are two independent main molecules (A and B and two dimethyl sulfoxide solvent molecules. In molecule A, the pyran ring is in a flattened sofa conformation, with the sp3-hydridized C atom forming the flap. In molecule B, the pyran ring is in a flattened boat conformation, with the sp3-hydridized C atom and the O atom deviating by 0.073 (3 and 0.055 (3 Å, respectively, from the plane of the other four atoms. The mean planes the pyrazole and phenyl rings form dihedral angles of 84.4 (2 and 84.9 (2°, respectively, for molecules A and B. In the crystal, N—H...O and N—H...N hydrogen bonds link the components of the structure into chains along [010]. In both solvent molecules, the S atoms are disordered over two sites, with occupancy ratios of 0.679 (4:0.321 (4 and 0.546 (6:0.454 (6.

  13. Crystal structure of 4-oxo-4H-chromene-3-carb-oxy-lic acid.

    Science.gov (United States)

    Ishikawa, Yoshinobu

    2015-08-01

    In the title compound, C10H6O4, also known as 3-carb-oxy-chromone, the non-H atoms of the chromone ring are essentially coplanar (r.m.s. deviation = 0.0057 Å), with the maximum deviation from their least-squares plane [0.011 (2) Å] being for a pyran C atom. The dihedral angle between the fused ring and plane of the carb-oxy group is 3.06 (2)°. An intra-molecular hydrogen bond is formed between the ring carbonyl O atom and the carb-oxy O-H atom, closing an S(6) loop. In the crystal, mol-ecules are assembled by stacking inter-actions [centroid-centroid distance between the benzene and pyran rings = 3.844 (3) Å] and C-H⋯O hydrogen bonds, generating a three-dimensional network. Short contacts are also observed between the carb-oxy O and C atoms [C=O⋯C=O = 3.002 (3) Å].

  14. Geranylated flavonoids displaying SARS-CoV papain-like protease inhibition from the fruits of Paulownia tomentosa.

    Science.gov (United States)

    Cho, Jung Keun; Curtis-Long, Marcus J; Lee, Kon Ho; Kim, Dae Wook; Ryu, Hyung Won; Yuk, Heung Joo; Park, Ki Hun

    2013-06-01

    SARS-CoV papain-like protease (PLpro) is an important antiviral target due to its key roles in SARS virus replication. The MeOH extracts of the fruits of the Paulownia tree yielded many small molecules capable of targeting PLpro. Five of these compounds were new geranylated flavonoids, tomentin A, tomentin B, tomentin C, tomentin D, tomentin E (1-5). Structure analysis of new compounds (1-5) by NMR showed that they all contain a 3,4-dihydro-2H-pyran moiety. This chemotype is very rare and is derived from cyclization of a geranyl group with a phenol functionality. Most compounds (1-12) inhibited PLpro in a dose dependent manner with IC50's raging between 5.0 and 14.4 μM. All new compounds having the dihydro-2H-pyran group showed better inhibition than their parent compounds (1 vs 11, 2 vs 9, 4 vs 12, 5 vs 6). In kinetic studies, 1-12 emerged to be reversible, mixed inhibitors.

  15. Afritoxinones A and B, dihydrofuropyran-2-ones produced by Diplodia africana the causal agent of branch dieback on Juniperus phoenicea.

    Science.gov (United States)

    Evidente, Antonio; Masi, Marco; Linaldeddu, Benedetto T; Franceschini, Antonio; Scanu, Bruno; Cimmino, Alessio; Andolfi, Anna; Motta, Andrea; Maddau, Lucia

    2012-05-01

    Two phytotoxic dihydrofuropyran-2-ones, named afritoxinones A and B, were isolated from liquid culture of Diplodia africana, a fungal pathogen responsible for branch dieback of Phoenicean juniper in Italy. Additionally, six others known metabolites were isolated and characterized: oxysporone, sphaeropsidin A, epi-sphaeropsidone, R-(-)-mellein, (3R,4R)-4-hydroxymellein and (3R,4S)-4-hydroxymellein. The structures of afritoxinones A and B were established by spectroscopic and optical methods and determined to be as (3aS(*),6R(*),7aS)-6-methoxy-3a,7a-dihydro-3H,6H-furo[2,3-b]pyran-2-one and (3aR(*),6R(*),7aS)-6-methoxy-3a,7a-dihydro-3H,6H-furo[2,3-b]pyran-2-one, respectively. The phytotoxic activity of afritoxinones A and B and oxysporone was evaluated on host (Phoenicean juniper) and non-host plant (holm oak, cork oak and tomato) by cutting and leaf puncture assay. Oxysporone proved to be the most phytotoxic compound. This study represents the first report of secondary metabolites produced by D. africana. In addition, the taxonomic implications of secondary metabolites in Botryosphaeriaceae family studies are discussed.

  16. Generation of Maillard compounds from inulin during the thermal processing of Agave tequilana Weber Var. azul.

    Science.gov (United States)

    Mancilla-Margalli, Norma A; López, Mercedes G

    2002-02-13

    During the cooking process of Agave tequilana Weber var. azul to produce tequila, besides the hydrolysis of inulin to generate fermentable sugars, many volatiles, mainly Maillard compounds, are produced, most of which may have a significant impact on the overall flavor of tequila. Exudates (agave juice) from a tequila company were collected periodically, and color, Brix, fructose concentration, and reducing sugars were determined as inulin breakdown took place. Maillard compounds were obtained by extraction with CH(2)Cl(2), and the extracts were analyzed by GC-MS. Increments in color, Brix, and reducing sugars were observed as a function of time, but a decrease in fructose concentration was found. Many Maillard compounds were identified in the exudates, including furans, pyrans, aldehydes, and nitrogen and sulfur compounds. The most abundant Maillard compounds were methyl-2-furoate, 2,3-dihydroxy-3,5-dihydro-6-methyl-4(H)-pyran-4-one, and 5-(hydroxymethyl)furfural. In addition, a series of short- and long-chain fatty acids was also found. A large number of the volatiles in A. tequilana Weber var. azul were also detected in tequila extracts, and most of these have been reported as a powerful odorants, responsible for the unique tequila flavor.

  17. Novos constituintes químicos das cascas do caule de Tabebuia heptaphylla New constituents from the trunk bark of Tabebuia heptaphylla

    Directory of Open Access Journals (Sweden)

    Fernanda Rodrigues Garcez

    2007-01-01

    Full Text Available A new triterpene, 3beta,6beta,21beta-trihydroxyolean-12-ene and a new iridoid, 8alpha-methyl-8beta-hydroxy-6beta-(3',4'-dimethoxybenzoyloxy-1 alpha,3alpha-dimethoxy-octahydro-cyclopenta[c]pyran were isolated from the trunk bark of a specimen of Tabebuia heptaphylla (Bignoniaceae collected in the "Pantanal" of Mato Grosso do Sul, Brazil. Twelve known compounds were also obtained in this work, comprising four iridoids, 6-O-p-hydroxybenzoylajugol, 6-O-p-methoxybenzoylajugol, 6-O-3",4"-dimethoxybenzoylajugol, 8alpha-methyl-8beta-hydroxy-6beta-(4'-hydroxybenzoyloxy-1alpha,3 alpha-dimethoxy-octahydro-cyclopenta[c]pyran, a cyclopentene dialdehyde, 2-formyl-5-(3',4'-dimethoxybenzoyloxy-3-methyl-2-cyclopentene-1-acetaldehyde, a phenylethanoid glycoside, verbascoside and three benzoic acid derivatives, p-hydroxybenzoic, p-methoxybenzoic and 3,4-dimethoxybenzoic acids, in addition to squalene, sitostenone and sitosterol. The antioxidant properties of the isolated compounds were also evaluated in this work.

  18. Design and synthesis of a novel series of histamine H3 receptor antagonists through a scaffold hopping strategy.

    Science.gov (United States)

    Gao, Zhongli; Hurst, William J; Hall, Daniel; Hartung, Ryan; Reynolds, William; Kang, Jiesheng; Nagorny, Raisa; Hendrix, James A; George, Pascal G

    2015-02-01

    Lead compounds 5-fluoro-2-methyl-N-[2-methyl-4-(2-methyl-[1,3']bipyrrolidinyl-1'-yl)-phenyl]-benzamide (1), tetrahydro-pyran-4-carboxylic acid [((2S,3'S)-2-methyl-[1,3']bipyrrolidinyl-1'-yl)-phenyl]-amide (2), and 3,5-dimethyl-isoxazole-4-carboxylic acid [((2S,3'S)-2-methyl-[1,3']bipyrrolidinyl-1'-yl)-phenyl]-amide (3) discovered in our laboratory, displayed high histamine H3 receptor (H3R) affinity, good selectivity and weak human Ether-à-go-go-Related Gene (hERG) channel affinity with desirable overall physico-chemical and pharmacokinetic (PK) profiles. Herein, we describe the design and synthesis of a novel series of H3R antagonists utilizing a scaffold hopping strategy. Further structure-activity relationship (SAR) studies of the series culminated in the identification of ((2S,3'S)-2-methyl-[1,3']bipyrrolidinyl-1'-yl)-naphthalene-2-carboxylic acid (tetrahydro-pyran-4-yl)-amide (4c) and -[4-((2S,3'S)-2-methyl-[1,3']bipyrrolidinyl-1'-yl)-phenyl]-N-(tetrahydro-pyran-4-yl)-acetamide (4d), which exhibited good H3R affinity in vitro, good selectivity, and desirable PK properties. Compounds 4c and 4d were also assessed in cardiac safety experiments. In particular, the effects of the compounds on action potentials recorded from ventricular myocytes isolated from guinea pigs were used to screen compounds that not only displayed a low affinity towards hERG channel, but also had lower interference with other cardiac ion channels. Compound 4c did not alter the major parameters in this model system at ⩽10 μM, and no significant induction of any major haemodynamic effect when intravenously administered at 3mg/kg dose to anaesthetized mongrel dogs. Compound 4c is a new promising lead as orally potent and selective H3R antagonist belonging to a distinct structural class.

  19. Random lasing from dye-doped negative liquid crystals using ZnO nanoparticles as tunable scatters

    Science.gov (United States)

    Li, Long-Wu; Shang, Zhen-Zhen; Deng, Luogen

    2016-09-01

    This work demonstrates the realization of a lasing in scattering media, which contains dispersive solution of ZnO nanoparticles (NPs) and laser dye 4-dicyanomethylene-2-methyle-6-(p-dimethylaminostyryl)-4H-pyran(DCM) in negative liquid crystals (LCs) that was injected into a cell. The lasing intensity of the dye-doped negative LC laser can be tuned from low to high if the NPs concentration is increased. The tunability of the laser is attributable to the clusters-sensitive feature in effective refractive index of the negative LCs. Such a tunable negative liquid crystal laser can be used in the fabrication of new optical sources, optical communication, and liquid crystal laser displays. Project supported by the Doctoral Science Research Start-up Funding of Guizhou Normal University, China (Grant No. 11904-0514162) and the National Natural Science Foundation of China (Grant No. 11474021).

  20. 8,8-Dimethyl-8,9-dihydro-7H-chromeno[2,3-b]quinoline-10,12-dione

    Directory of Open Access Journals (Sweden)

    Thothadri Srinivasan

    2013-02-01

    Full Text Available In the title compound, C18H15NO3, the fused benzopyran and pyridine rings are essentially coplanar [r.m.s. deviation = 0.0533 Å with a maximum deviation of 0.080 (1 Å for a benzene C atom]. The cyclohexanone ring adopts an envelope conformation with the dimethyl-substituted C atom 0.660 (2 Å out of the plane formed by the remaining ring atoms (r.m.s. deviation = 0.0305 Å. The dihedral angle between the mean planes of the pyran and cyclohexanone rings is 12.95 (6°. In the crystal, molecules are linked via C—H...O hydrogen bonds, leading to chains running along [011].

  1. Predictive Modeling of Antioxidant Coumarin Derivatives Using Multiple Approaches: Descriptor-Based QSAR, 3D-Pharmacophore Mapping, and HQSAR

    Directory of Open Access Journals (Sweden)

    Indrani MITRA

    2016-09-01

    Full Text Available The inability of the systemic antioxidants to alleviate the exacerbation of free radical formation from metabolic outputs and environmental pollutants claims an urgent demand for the identification and design of new chemical entities with potent antioxidant activity. In the present work, different QSAR approaches have been utilized for identifying the essential structural attributes imparting a potential antioxidant activity profile of the coumarin derivatives. The descriptor-based QSAR model provides a quantitative outline regarding the structural prerequisites of the molecules, while 3D pharmacophore and HQSAR models emphasize the favourable spatial arrangement of the various chemical features and the crucial molecular fragments, respectively. All the models infer that the fused benzene ring and the oxygen atom of the pyran ring constituting the parent coumarin nucleus capture the prime pharmacophoric features, imparting superior antioxidant activity to the molecules. The developed models may serve as indispensable query tools for screening untested molecules belonging to the class of coumarin derivatives.

  2. Pentafluorophenylammonium triflate (PFPAT catalyzed facile construction of substituted chromeno[2,3-d]pyrimidinone derivatives and their antimicrobial activity

    Directory of Open Access Journals (Sweden)

    Majid Ghashang

    2014-03-01

    Full Text Available A new, simple thermally efficient and solvent-free condensation of 2-amino-3-cyano-6-methyl-4-phenyl-4H-pyran-5-ethylcarboxylate derivatives with coumarin-3-carboxylic acid employing pentafluorophenylammonium triflate (PFPAT as an inexpensive organocatalyst for the synthesis of a series of ethyl 4,5-dihydro 7-methyl-2-(2-oxo-2H-chromen-3-yl-4-oxo-5-aryl-3H-chromeno[2,3-d]pyrimidine-6-carboxylate derivatives is described. This method has the advantages of high yields, a cleaner reaction, simple methodology, short reaction times, easy workup, and greener conditions. All the compounds were evaluated for their in vitro antimicrobial activity against different bacterial and fungal strains.

  3. Synthesis and Biological Evaluation of Some New Coumarin Derivatives

    Directory of Open Access Journals (Sweden)

    M. Y. El-Kady

    2003-02-01

    Full Text Available Pyrimidino[5`,4`-6,5]-,pyridino[3`,2`-6,5]- and pyrrolo[3`,2`-5,6]4H-pyrano-[3,2-c][1]benzopyran-6-one derivatives (5-7 and 10 could be obtained via reaction of 2-amino-4-(p-bromophenyl-3-cyano(carboethoxy-4H,5H-pyrano[3,2-c][1]benzopyran-5-ones (3a,b with a variety of reagents. Alkylation of (3b with either 2-furoyl chloride or chloroacetyl chloride gave the 2-N-substituted derivatives (9a,b. Benzofurano[3,2-b]4H-pyran derivative (12 was also prepared. The antimicrobial activity of the prepared compounds was tested.

  4. A fluorescence switch based on a controllable photochromic naphthopyran group

    Energy Technology Data Exchange (ETDEWEB)

    Chen Lizhen [Faculty of Chemistry, Northeast Normal University, Changchun 130024 (China); Wang Guang, E-mail: wangg923@nenu.edu.cn [Faculty of Chemistry, Northeast Normal University, Changchun 130024 (China); Zhao Xiancai [Faculty of Chemistry, Northeast Normal University, Changchun 130024 (China)

    2011-08-15

    A fluorescence switch based on photoisomerization of naphthopyran (NP) has been designed by employing 2-(pyridin-2-yl)-benzimidazole (BPI) and the naphthopyran containing two pyran rings (NP) as fluorescent dye and photochromic compound, respectively. The fluorescence switch of benzimidazole derivative can be modulated either by controlling the irradiation time of UV light or by adjusting the amount ratio of fluorescent benzimidazole derivative to photochromic naphthopyran in both solution and polymethyl methacrylate (PMMA) film. The experimental results indicated that the decrease of fluorescence intensity of benzimidazole derivative is attributed to the interaction of benzimidazole with naphthopyran. - Highlights: > Naphthopyran was first used to fabricate fluorescence switch with benzimidazole derivative. > Fluorescence intensity can be modulated by controlling the UV irradiation time. > Fluorescence intensity can be adjusted by changing the ratio of benzimidazole derivative to naphthopyran. > Decrease of fluorescence intensity is attributed to the interaction of benzimidazole derivative and naphthopyran.

  5. Optimization of lasing in an inverted-opal titania photonic crystal cavity as an organic solid-state dye-doped laser.

    Science.gov (United States)

    Zhang, Dingke; Chen, Shijian; Jiang, Maohua; Ye, Lijuan

    2014-11-10

    Lasing performance of a dye-doped laser by encapsulating orange fluorescent dye 4-(Dicyanomethylene)-2-methyl-6-(4-dimethylaminostyryl)-4H-pyran (DCM) with different concentrations in a highly ordered three-dimensional (3D) inverted-opal titania (TiO2) photonic crystal (PC) microcavity was studied. The lasing threshold and laser quality were improved by optimizing the concentration of the laser dye DCM. When the concentration of DCM is optimized to 10-4  mol/l, the photoluminescence (PL) efficiency of DCM is sufficient to achieve lasing emission and meanwhile no fluorescence quantum quenching occurs. Therefore, the emission spectrum was greatly narrowed and the threshold was significantly improved, which reached 0.8  mJ pulse-1 cm-2. Our findings are promising results toward the realization of fabricating a highly efficient low-threshold organic laser.

  6. Lewis acid catalyzed cyclization of glycals/2-deoxy-D-ribose with arylamines: additional findings on product structure and reaction diastereoselectivity.

    Science.gov (United States)

    Du, Chengtang; Li, Fulong; Zhang, Xuefeng; Hu, Wenxiang; Yao, Qizheng; Zhang, Ao

    2011-11-01

    The cyclization reactions of arylamines with 2-deoxy-D-ribose or glycals were reinvestigated in the current report. In the montmorillonite KSF- or InCl(3)-initiated reactions of 2-deoxy-D-ribose with arylamines, a pair of diastereomeric tetrahydro-2H-pyran-fused tetrahydroquinolines was obtained in a nearly 1:1 ratio where the structure of one diastereomer was incorrectly assigned in the literature. Meanwhile, the diastereoselectivity in InBr(3)-catalyzed cyclization of glycals with arylamines was also incorrectly reported previously. It was found that high diastereomeric selectivity was achieved only when a C5-substituted glycal was used; otherwise, a pair of diastereomers was obtained in moderate yield with 1:1 diastereomeric ratio. Furthermore, tetrahydrofuran-fused tetrahydroquinolines 5b and 5b' were also prepared successfully by using TBDPS-protected ribose as the glycal precursor and montmorillonite KSF as the activator.

  7. A green approach to the production of 2-pyridone derivatives promoted by infrared irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez, F.; De la Cruz, F.; Lopez, J.; Pena, E.; Vazquez, M. A. [Universidad de Guanajuato, Dapartamento de Quimica, Noria Alta s/n, 36050 Guanajuato, Gto. (Mexico); Delgado, F. [IPN, Escuela Nacional de Ciencias Biologicas, Departamento de Quimica Organica, Prol. Carpio y Plan de Ayala s/n, 11340 Mexico D. F. (Mexico); Alcaraz, Y.; FRobles, J.; Martinez A, M., E-mail: mvazquez@ugto.mx [Universidad de Guanajuato, Departamento de Farmacia, Noria Alta s/n, 36050 Guanajuato, Gto. (Mexico)

    2014-10-01

    An alternative is presented by promoting a reaction with infrared irradiation to obtain different 4-aryl-3-cyano-5-ethoxycarbonyl-6-methyl-2-pyridone derivatives 9 a-k. The process was carried out with a green approach from the corresponding 4 H-pyrans, using mild reaction conditions and infrared irradiation as the energy source. In the first stage, the reaction produced 1,2,3,4-tetrahydropyridine-2-one derivatives 8 a-k, followed by an oxidative step to afford the target molecules in good yields. The structure of products 9 a-k was confirmed by Ft-IR, {sup 1}H NMR and {sup 13}C NMR spectroscopic techniques and X-ray diffraction. It was found that the efficiency of the reaction depends on the catalyst and the solvent, as well as on the aldehyde substituents. (Author)

  8. Pyroligneous acid-the smoky acidic liquid from plant biomass.

    Science.gov (United States)

    Mathew, Sindhu; Zakaria, Zainul Akmar

    2015-01-01

    Pyroligneous acid (PA) is a complex highly oxygenated aqueous liquid fraction obtained by the condensation of pyrolysis vapors, which result from the thermochemical breakdown or pyrolysis of plant biomass components such as cellulose, hemicellulose, and lignin. PA produced by the slow pyrolysis of plant biomass is a yellowish brown or dark brown liquid with acidic pH and usually comprises a complex mixture of guaiacols, catechols, syringols, phenols, vanillins, furans, pyrans, carboxaldehydes, hydroxyketones, sugars, alkyl aryl ethers, nitrogenated derivatives, alcohols, acetic acid, and other carboxylic acids. The phenolic components, namely guaiacol, alkyl guaiacols, syringol, and alkyl syringols, contribute to the smoky odor of PA. PA finds application in diverse areas, as antioxidant, antimicrobial, antiinflammatory, plant growth stimulator, coagulant for natural rubber, and termiticidal and pesticidal agent; is a source for valuable chemicals; and imparts a smoky flavor for food.

  9. Crystal structure of canagliflozin hemihydrate

    OpenAIRE

    Liu, Kai-Hang; Gu, Jian-Ming; Hu, Xiu-Rong; Tang, Gu-ping

    2016-01-01

    There are two canagliflozin mol­ecules (A and B) and one water mol­ecule in the asymmetric unit of the title compound, C24H25FO5S·0.5H2O [systematic name: (2S,3R,4R,5S,6R)-2-(3-{[5-(4-fluoro­phen­yl)thio­phen-2-yl]meth­yl}-4-methylphen­yl)-6-(hy­droxy­meth­yl)-3,4,5,6-tetra­hydro-2H-pyran-3,4,5-triol hemihydrate]. The dihedral angles between the methyl­benzene and thio­phene rings are 115.7 (4) and 111.7 (4)°, while the dihedral angles between the fluoro­benzene and thio­phene rings are 24.2 ...

  10. Crystal structure of canagliflozin hemihydrate

    OpenAIRE

    Kai-Hang Liu; Jian-Ming Gu; Xiu-Rong Hu; Gu-Ping Tang

    2016-01-01

    There are two canagliflozin molecules (A and B) and one water molecule in the asymmetric unit of the title compound, C24H25FO5S·0.5H2O [systematic name: (2S,3R,4R,5S,6R)-2-(3-{[5-(4-fluorophenyl)thiophen-2-yl]methyl}-4-methylphenyl)-6-(hydroxymethyl)-3,4,5,6-tetrahydro-2H-pyran-3,4,5-triol hemihydrate]. The dihedral angles between the methylbenzene and thiophene rings are 115.7 (4) and 111.7 (4)°, while the dihedral angles between the fluorobenzene and thiophene rings are 24.2 (6) and 20.5 (9...

  11. All-polymer organic semiconductor laser chips: Parallel fabrication and encapsulation

    DEFF Research Database (Denmark)

    Vannahme, Christoph; Klinkhammer, Sönke; Christiansen, Mads Brøkner

    2010-01-01

    Organic semiconductor lasers are of particular interest as tunable visible laser light sources. For bringing those to market encapsulation is needed to ensure practicable lifetimes. Additionally, fabrication technologies suitable for mass production must be used. We introduce all-polymer chips...... comprising encapsulated distributed feedback organic semiconductor lasers. Several chips are fabricated in parallel by thermal nanoimprint of the feedback grating on 4? wafer scale out of poly(methyl methacrylate) (PMMA) and cyclic olefin copolymer (COC). The lasers consisting of the organic semiconductor...... tris(8- hydroxyquinoline) aluminum (Alq3) doped with the laser dye 4-dicyanomethylene-2- methyl-6-(p-dimethylaminostyril)-4H-pyrane (DCM) are hermetically sealed by thermally bonding a polymer lid. The organic thin film is placed in a basin within the substrate and is not in direct contact to the lid...

  12. High Excitation Transfer Efficiency from Energy Relay Dyes in Dye-Sensitized Solar Cells

    KAUST Repository

    Hardin, Brian E.

    2010-08-11

    The energy relay dye, 4-(Dicyanomethylene)-2-methyl-6-(4- dimethylaminostyryl)-4H-pyran (DCM), was used with a near-infrared sensitizing dye, TT1, to increase the overall power conversion efficiency of a dye-sensitized solar cell (DSC) from 3.5% to 4.5%. The unattached DCM dyes exhibit an average excitation transfer efficiency (EÌ?TE) of 96% inside TT1-covered, mesostructured TiO2 films. Further performance increases were limited by the solubility of DCM in an acetonitrile based electrolyte. This demonstration shows that energy relay dyes can be efficiently implemented in optimized dye-sensitized solar cells, but also highlights the need to design highly soluble energy relay dyes with high molar extinction coefficients. © 2010 American Chemical Society.

  13. Crystal structure of 3-amino-1-(4-hydroxyphenyl-1H-benzo[f]chromene-2-carbonitrile

    Directory of Open Access Journals (Sweden)

    Mehmet Akkurt

    2015-08-01

    Full Text Available In the title compound, C20H14N2O2, the hydroxybenzene ring is almost perpendicular to the mean plane of the naphthalene ring system, making a dihedral angle of 85.56 (4°. The 4H-pyran ring fused with the naphthalene ring system has a flattened boat conformation. In the crystal, O—H...N and N—H...O hydrogen bonds link the molecules into a supramolecular layer in the bc plane; N—H...π interactions also contribute to this arrangement. The layers are linked by weak by C—H...π and π–π [inter-centroid separation = 3.8713 (7 Å] interactions.

  14. Crystal structure of (7-fluoro-2-oxo-2H-chromen-4-ylmethyl morpholine-4-carbodithioate

    Directory of Open Access Journals (Sweden)

    B. R. Anitha

    2015-12-01

    Full Text Available In the title compound, C15H14FNO3S2, the 2H-chromene ring system is close to being planar (r.m.s. deviation = 0.024 Å and the morpholine ring adopts a chair conformation. The dihedral angle between the 2H-chromene ring system and the morpholine ring (all atoms is 88.21 (11°. In the crystal, inversion dimers linked by pairs of very weak C—H...F hydrogen bonds generate R22(8 loops; C—H...O hydrogen bonds connect the dimers into [010] chains. Weak aromatic π–π stacking interactions between the pyran rings of the chromene systems [centroid–centroid distance = 3.6940 (16 Å] are also observed.

  15. 2-Amino-4-(2-chlorophenyl-7,7-dimethyl-5-oxo-5,6,7,8-tetrahydro-4H-chromene-3-carbonitrile hemihydrate

    Directory of Open Access Journals (Sweden)

    Fang-Ming Wang

    2012-03-01

    Full Text Available The asymmetric unit of the title compound, C18H17ClN2O2·0.5H2O, contains two organic molecules and one solvent water molecule. In each organic molecule, the cyclohexene ring adopts an envelope conformation with the C atom connecting the two methyl groups on the flap; the 4H-pyran ring is nearly planar [maximum deviation = 0.113 (3 Å in one molecule and 0.089 (3 Å in the other molecule] and is approximately perpendicular to the chlorophenyl ring [dihedral angle = 86.43 (15° in one molecule and 89.73 (15° in the other molecule]. Intermolecular N—H...N, N—H...O, O—H...O and O—H...Cl hydrogen bonding is present in the crystal.

  16. 4-Oxo-N-phenyl-4H-chromene-2-carboxamide and of a new polymorph of 7-methoxy-4-oxo-N-p-tolyl-4H-chromene-2-carboxamide and its hemihydrate.

    Science.gov (United States)

    Reis, Joana; Gaspar, Alexandra; Borges, Fernanda; Gomes, Ligia R; Low, John Nicolson

    2013-12-15

    4-Oxo-N-phenyl-4H-chromene-2-carboxamide, C16H11NO3, crystallizes in the space group P2(1)/n and its derivative 7-methoxy-4-oxo-N-p-tolyl-4H-chromene-2-carboxamide, C18H15NO4, forms two polymorphs which crystallize in the space groups P2(1)/c and P1. The structures have an anti-rotamer conformation about the C-N bond; however, the amide O atom can be either trans- or cis-related to the O atom of the pyran ring. The latter compound also crystallizes as a hemihydrate, C18H15NO4·0.5H2O, in the space group C2/c. This compound has a similar structure to that of the unsolvated compound.

  17. 6-Iodo-4-oxo-4H-chromene-3-carbaldehyde

    Directory of Open Access Journals (Sweden)

    Yoshinobu Ishikawa

    2014-07-01

    Full Text Available In the title compound, C10H5IO3, an iodinated 3-formylchromone derivative, the non-H atoms are essentially coplanar (r.m.s. deviation = 0.0259 Å, with the largest deviation from the least-squares plane [0.056 (5 Å] being found for the formyl O atom. In the crystal, molecules are linked through I...O halogen bonds [I...O = 3.245 (4 Å, C—I...O = 165.95 (13 and C=O...I = 169.7 (4°] along [101]. The supramolecular chains are assembled into layers via π–π stacking interactions along the b axis [shortest centroid–centroid distance between the pyran and benzene rings = 3.558 (3 Å].

  18. (R,S-2′-Amino-6′-methyl-2,5′,5′-trioxo-6′H-spiro[indoline-3,4′-pyrano[3,2-c][2,1]benzothiazine]-3′-carbonitrile dimethylformamide monosolvate

    Directory of Open Access Journals (Sweden)

    Svitlana V. Shishkina

    2014-07-01

    Full Text Available The title solvate, C20H14N4O4S·C3H7NO, comprises a stereogenic centre but the centrosymmetric space group causes the presence of the racemate in the crystal. The spiro-joined fragments are almost orthogonal, with a dihedral angle of 86.8 (2° between the mean planes of the pyrane ring and the dihydroindolone ring system. The atoms of the indolinone bicycle are coplanar, with an r.m.s. deviation of 0.005 Å. In the crystal, pairs of N—H...O hydrogen bonds link the molecules into centrosymmetric dimers which are linked to the dimethylformamide solvent molecules by further N—H...O hydrogen bonds. N—H...N hydrogen bonds link neighbouring dimers into [010] chains.

  19. Pyranonaphthoquinones - isolation, biology and synthesis: an update.

    Science.gov (United States)

    Naysmith, Briar J; Hume, Paul A; Sperry, Jonathan; Brimble, Margaret A

    2017-01-04

    Covering: 2008 to 2015. A review on the isolation, biological activity and synthesis of pyranonaphthoquinone natural products from 2008-2015 is providedThis review discusses the isolation, biological activity and synthesis of pyranonaphthoquinone natural products, covering the years 2008-2015. The pyranonaphthoquinones are a group of metabolites sharing a common naphtho[2,3-c]pyran-5,10-dione ring system that have been isolated from a wide range of microorganisms, plants and insects. In addition to their synthetically challenging molecular structures, pyranonaphthoquinones exhibit a wide array of biological activity, including anti-bacterial, anti-fungal and anti-cancer properties. The therapeutic potential of these compounds has led to a dynamic interplay between total synthesis and biological evaluation.

  20. Antibacterial Bisabolane-Type Sesquiterpenoids from the Sponge-Derived Fungus Aspergillus sp.

    Directory of Open Access Journals (Sweden)

    Chang-Yun Wang

    2012-01-01

    Full Text Available Four new bisabolane-type sesquiterpenoids, aspergiterpenoid A (1, (−-sydonol (2, (−-sydonic acid (3, and (−-5-(hydroxymethyl-2-(2′,6′,6′-trimethyltetrahydro-2H- pyran-2-ylphenol (4 together with one known fungal metabolite (5 were isolated from the fermentation broth of a marine-derived fungus Aspergillus sp., which was isolated from the sponge Xestospongia testudinaria collected from the South China Sea. Four of them (1–4 are optically active compounds. Their structures and absolute configurations were elucidated by using NMR spectroscopic techniques and mass spectrometric analysis, and by comparing their optical rotations with those related known analogues. Compounds 1–5 showed selective antibacterial activity against eight bacterial strains with the MIC (minimum inhibiting concentrations values between 1.25 and 20.0 µM. The cytotoxic, antifouling, and acetylcholinesterase inhibitory activities of these compounds were also examined.

  1. Optical Features of Spherical Gold Nanoparticle-Doped Solid-State Dye Laser Medium

    Science.gov (United States)

    Hoa, D. Q.; Lien, N. T. H.; Duong, V. T. T.; Duong, V.; An, N. T. M.

    2016-05-01

    The development of a new laser medium based on gold nanoparticle/dye-doped polymethylmethacrylate (PMMA) has been investigated. In particular, gold nanoparticles with small (16 nm diameter) spherical shape strongly influenced the absorption and fluorescence emission spectra of [2-[2-[4-(dimethylamino)phenyl]ethenyl]-6-methyl-4 H-pyran-4-ylidene]-propanedinitrile (DCM) laser dye. Fluorescence quenching and enhancement of DCM emission were observed for various concentrations of gold nanoparticles (GNPs). Fluorescence intensity enhancement was recorded for the sample containing 1.5 × 1010 par/mL GNPs and doped with 3 × 10-5 mol/L DCM. Thermal photodegradation was significantly decreased by using low pump energy for laser emission.

  2. Phenolic compounds from Anaphalis aureo-punctata

    Institute of Scientific and Technical Information of China (English)

    WU Yan-Qi; LOU Ning; LI Yu

    2003-01-01

    @@ From the ethanolic extract of the whole plant of Anaphalis aureo-punctata, a new acylated flavonoid glycoside 3-O-kaempferol-3-O-acetyl-6-O-(p-coumaroyl)-β-D-glucopyranoside (1), and five known phenolic compounds 3-O-kaempferol-6- O- ( p-coumaroyl )-β-D-glucopyranoside ( 2 ), kaempferol-3- O-β-D-glucopyranoside 3,6-(4′-hydroxystyryl)-4-methoxy-2-pyrone (4), 2H-pyran-2-one, 6-[ 2-( 4-(β-D-glucopyranosyloxy ) phenyl ) ethenyl ]-4-methoxy-( E ) (5) and 4-hydroxy-3-methoxycinnamic hexacosyl ester (6) were isolated. Their structures were established by spectral methods (UV, IR, MS, 1D, 2D-NMR). The flavonoid glycosides, 1, 2 and 3 showed markedly inhibited oxidative DNA strand breaks induced by Fenton reaction and NADH/PMS in a concentration-dependent manner.

  3. Reduction of Concentration Quenching in a Nondoped DCM Organic Light-Emitting Diode

    Institute of Scientific and Technical Information of China (English)

    LIU Zhen-Gang; CHEN Zhi-Jian; GONG Qi-Huang

    2005-01-01

    @@ We obtain a nondoped red organic light-emitting diode (OLED) structure ITO/pc-PPV (~30 nm)/DCM (~30 nm)/BCP (~30nm)/Mg:Ag, where DCM refers to 4-(dicyanomethylene)-2-methyl-6-[(4-dimethylaninostyryl)-4-H-pyran]. The OLED shows pure and stable red luminescence depending on the driving voltages. The maximum luminance is 330 Cd/m2 and the turn-on voltage is as low as ~2 V. The reason why the concentration quenching of DCM could be reduced in this structure is investigated. In the preparation process, both the hole-transporting layer and the emitter layer are formed by the spin-coated method. It is believed that this method can lead to a new way to avoid the concentration quenching of red-emitting materials.

  4. (S,S,S,S)-Nebivolol hydro-chloride hemihydrate.

    Science.gov (United States)

    Rousselin, Yoann; Bruel, Amelie; Clavel, Alexandre

    2012-12-01

    The asymmetric unit of the title hydrated salt, C22H26F2NO4(+)·Cl(-)·0.5H2O, consists of an (S,S,S,S)-nebivolol {nebivol = bis-[2-(6-fluoro-3,4-dihydro-2H-1-benzopyran-2-yl)-2-hy-droxy-eth-yl]ammonium} cation, a chloride anion and a half-occupancy water mol-ecule. The dihedral angle between the mean planes of the benzene rings is 50.34 (12)°. The pyran rings adopt half-chair conformations. The crystal packing features O-H⋯O hydrogen bonds and weak N-H⋯Cl, O-H⋯Cl, and O-H⋯Cl inter-actions, producing layers along (010).

  5. (S,S,S,S-Nebivolol hydrochloride hemihydrate

    Directory of Open Access Journals (Sweden)

    Yoann Rousselin

    2012-12-01

    Full Text Available The asymmetric unit of the title hydrated salt, C22H26F2NO4+·Cl−·0.5H2O, consists of an (S,S,S,S-nebivolol {nebivol = bis[2-(6-fluoro-3,4-dihydro-2H-1-benzopyran-2-yl-2-hydroxyethyl]ammonium} cation, a chloride anion and a half-occupancy water molecule. The dihedral angle between the mean planes of the benzene rings is 50.34 (12°. The pyran rings adopt half-chair conformations. The crystal packing features O—H...O hydrogen bonds and weak N—H...Cl, O—H...Cl, and O—H...Cl interactions, producing layers along (010.

  6. White organic light emitting devices with hybrid emissive layers combining phosphorescence and fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Lei Gangtie; Chen Xiaolan; Wang Lei; Zhu Meixiang; Zhu Weiguo [Key Lab of Environmental-friendly Chemistry and Application of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan 411105 (China); Wang Liduo; Qiu Yong [Key Lab of Organic-Optoelectronics and Molecular Sciences of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing 100084 (China)], E-mail: lgt@xtu.edu.cn

    2008-05-21

    We fabricated a white organic light-emitting diode (WOLED) by hybrid emissive layers which combined phosphorescence with fluorescence. In this device, the thin layer of 4-(dicyanomethylene)-2-(t-butyl)-6-(1, 1, 7, 7-tetramethyljulolidyl-9-enyl)-4H-pyran played the role of undoped red emissive layer which was inserted between two blue phosphorescence emissive layers. The blue phosphorescent dye was bis[(4, 6-difluorophenyl)-pyridinato-N, C{sup 2}] (picolinato) Ir(III), which was doped in the host material, N, N'-dicarbazolyl-1, 4-dimethene-benzene. The WOLED showed stable Commission Internationale de L'Eclairage coordinates and a high efficency of 9.6 cd A{sup -1} when the current density was 1.8 A m{sup -2}. The maximum luminance of the device achieved was 17 400 cd m{sup -2} when the current density was 3000 A m{sup -2}.

  7. The nanometer cavity structure of a photochromic naphthopyran

    Science.gov (United States)

    Tan, Tingfeng; Fu, Yifang; Han, Jie; Pang, Meili; Meng, Jiben

    2005-05-01

    A novel photochromic compound, 3, 3-(2, 4-dimethoxy-phenyl)-3H-naphtho [2, 1-b] pyran (Compound I), was synthesized and the structure was determined by X-ray diffraction and TEM. Introduction of methoxy groups in the 2, 4-position of the phenyl moiety affects the whole arrangement of molecular self-assembly. The structure displays motifs formed by only weak C-H⋯π interactions. The motifs thus generated show cavities, which could serve as hosts for complexation. To our surprise, it was shown that the aperture of the cavity structure is up to nanometer level by TEM, which is rarely seen in organic compound. Moreover, the photochromic properties of the compound I in solid state and polyvinyl butyral film were studied. The results showed compound I exhibited good reversible photochromism.

  8. The preparation of 3-substituted-1,5-dibromopentanes as precursors to heteracyclohexanes

    Directory of Open Access Journals (Sweden)

    Piotr Kaszynski

    2011-03-01

    Full Text Available The methodology to prepare 3-substituted 1,5-dibromopentanes I and their immediate precursors, which include 3-substituted 1,5-pentanediols VII or 4-substituted tetrahydropyrans VIII, is surveyed. Such dibromides I are important intermediates in the preparation of liquid crystalline derivatives containing 6-membered heterocyclic rings. Four dibromides 1a–1d containing simple alkyl and more complex fragments at the 3-position were prepared. 3-Propyl- and 3-pentyl-pentane-1,5-diol (2a,b were prepared starting from either glutaconate or malonate diesters, while tetrahydropyrans 3c and 3d were obtained from tetrahydro-4H-pyran-4-one. The advantages and disadvantages of each route are discussed. Dibromides 1c and 1d were used to prepare sulfonium zwitterions 11c and 11d.

  9. New Bicyclic Cembranoids from the South China Sea Soft Coral Sarcophyton trocheliophorum

    Science.gov (United States)

    Liang, Lin-Fu; Chen, Wen-Ting; Li, Xu-Wen; Wang, He-Yao; Guo, Yue-Wei

    2017-04-01

    Nine new bicyclic cembranoids, sarcophytrols M-U(1-9), were isolated from the South China Sea soft coral Sarcophyton trocheliophorum as minor components, along with one known related cembranoid 10. Their structures were elucidated by detailed spectroscopic analysis and chemical conversion. The chemical structures of these metabolites are characterized by the different patterns of the additional cyclization within the 14-member skeleton, which leading to the formation of furan, pyran, oxepane, and peroxyl rings, respectively. Among them, sarcophytrols R and S(6 and 7) share a rare decaryiol skeleton with an unusual C12/C15 cyclization. In addition, the absolute configurations of sarcophytrols M and T(1 and 8) were determined by the modified Mosher’s method. The research of these new secondary metabolites provided a further understanding of the diversity of cyclized cembranoids from the title species.

  10. 8-Fluoro-4-oxo-4H-chromene-3-carbaldehyde

    Directory of Open Access Journals (Sweden)

    Yoshinobu Ishikawa

    2014-07-01

    Full Text Available In the title compound, C10H5FO3, the non-H atoms of the 8-fluorochromone unit are essentially coplanar (r.m.s. deviation = 0.0259 Å, with a largest deviation from the mean plane of 0.0660 (12 Å for the chromone carbonyl O atom. The formyl group is twisted with respect to the attached ring [C—C—C—O torsion angles = −11.00 (19 and 170.81 (11°]. In the crystal, molecules are linked via weak C—H...O hydrogen bonds along the a axis and [-101], forming corrugated layers parallel to (010. In addition, π–π stacking interactions [centroid–centroid distance between the planes of the pyran and benzene rings = 3.519 (2 Å] are observed between these layers.

  11. Crystal structure of 7-bromo-4-oxo-4H-chromene-3-carbaldehyde

    Directory of Open Access Journals (Sweden)

    Yoshinobu Ishikawa

    2014-09-01

    Full Text Available In the title compound, C10H5BrO3, a brominated 3-formylchromone derivative, all atoms are essentially coplanar (r.m.s. = 0.0631 Å for the non-H atoms, with the largest deviation from the least-squares plane [0.215 (3 Å] being for the formyl O atom. In the crystal, molecules are linked into tapes through C—H...O hydrogen bonds and these tapes are assembled by stacking interactions [centroid–centroid distance between the pyran rings = 3.858 (3 Å] to form supramolecular layers that stack along the c axis.

  12. GC-MS ANALYSIS OF SOME BIOACTIVE CONSTITUENTS OF THE LEAVES OF DESMODIUM GYRANS DC.

    Directory of Open Access Journals (Sweden)

    S.Gopalakrishnan

    2012-08-01

    Full Text Available Desmodium gyrans DC is one of the medicinally valuable plants belonging to the family Fabaceae, commonly known as “Thozhukanni” in Tamil and ‘ Namaskari’ in Sanskrit. Traditionally leaves are used as antidote, cardiac-tonic and for wound healing. In the present study the ethanolic extract of Desmodium gyrans has been subjected to GC-MS analysis. Eighteen chemical constituents have been identified, The major chemical constituents are: 4,5-Dihydro-2-amino-4-(2,4-dichlorophenyl-7-methyl-5-oxo- pyrano[3,2-c]pyran-3-carbonitrile (59.07%, Pentaborane (13.86%, Pentanedinitrile (6.63% and 3-Chloro-1-butyne, (4.82%.

  13. In vitro and in vivo studies of ambruticin (W7783): new class of antifungal antibiotics.

    Science.gov (United States)

    Ringel, S M

    1978-05-01

    Ambruticin is a cyclopropyl-pyran acid, representing a new class of antibiotics. It has a relatively broad antifungal spectrum in vitro and is highly active against dimorphic as well as filamentous organisms. Of 24 strains of dermatophytic fungi tested, the majority were susceptible to ambruticin at 0.049 mug/ml or less. The minimal inhibitory concentration for the systemic fungi Histoplasma capsulatum and Blastomyces dermatitidis was 0.049 to 0.39 mug/ml. Ambruticin is fungicidal for metabolizing cells of Microsporum fulvum and does not cause cell leakage of 260-nm absorbing material. The antibiotic is effective orally as well as topically in guinea pigs experimentally infected with Trichophyton mentagrophytes. In mice, a single oral dose of 75 mg/kg produced peak serum levels of 45 mug/ml in 1 h with a serum half-life of 3.1 h. Excretion of the antibiotic is principally by the biliary route.

  14. Antioxidant effects of green tea polyphenols

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The unprecedented interest in the antioxidant activity of green tea polyphenols (GTP) is due to the apparent health benefits of tea drinking and the experimental results with the polyphenols. The results suggest that the galloylated catechins show stronger antioxidant effect than that of nongalloylated catechins and the double bond in C ring also plays an important role in this effect. There are synergic effects between different catechins and the antioxidant effectof (+)-epimers is stronger than that of (-)-epimers. The active site to scavenge free radicals mainly locates in p-hydroxyl of phenol in gallic acid and hydroxyl of phenol in the pyrane also shows activity. The large π bond in chromane and benzene ring of catechin is the structure base for their antioxidant effects. The prevent effect of GTP against diseases and their redox regulation in cell signal pathway are very important to be studied in the future.

  15. Transition metal complexes with oxygen donor ligands: a synthesis, spectral, thermal and antimicrobial study

    Directory of Open Access Journals (Sweden)

    VAIBHAV N. PATANGE

    2008-10-01

    Full Text Available Transition metal complexes of chalcones derived from the conden¬sation of 3-acetyl-6-methyl-2H-pyran-2,4(3H-dione (dehydroacetic acid and p-methoxybenzaldehyde (HL1 or p-nitrobenzaldehyde (HL2 were synthesized and characterized by elemental analysis, conductometry, thermal analysis, magnetic measurements, IR, 1H-NMR, UV–Vis spectroscopy and a microbial study. From the analytical and thermal data, the stoichiometry of the complexes was found to be 1:2 (metal:ligand. The molar conductance data revealed that all the metal chelates were non-electrolytes. The thermal stability of the complexes was studied by thermogravimetry and the decomposition schemes of the complexes are given. The ligands and their metal complexes were screened for antibacterial activity against Staphylococcus aureus and Escherichia coli, and fungicidal activity against Aspergillus flavus, Curvularia lunata and Penicillium notatum.

  16. Rhodium(III)-Catalyzed ortho C-H Heteroarylation of (Hetero)aromatic Carboxylic Acids: A Rapid and Concise Access to π-Conjugated Poly-heterocycles.

    Science.gov (United States)

    Qin, Xurong; Li, Xiaoyu; Huang, Quan; Liu, Hu; Wu, Di; Guo, Qiang; Lan, Jingbo; Wang, Ruilin; You, Jingsong

    2015-06-08

    Rh(III)-catalyzed oxidative C-H/C-H cross-coupling between (hetero)aromatic carboxylic acids and various heteroarenes has been accomplished to construct highly functionalized ortho-carboxy-substituted bi(hetero)aryls. The use of a carboxy group as the directing group obviates tedious steps for installation and removal of extra directing groups, and enables a facile one-step synthesis of ortho-carboxy bi(hetero)aryls. The method provides opportunities for rapid assembly of a library of important fluorene and coumarin-type poly-heterocycles through intramolecular electrophilic substitution or oxidative lactonization. As illustrative examples, the strategy developed herein greatly streamlines accesses to a variety of appealing polyheterocycles such as DTPO (5H-dithieno[3,2-b:2',3'-d]pyran-5-one), CPDTO (cyclopentadithiophen-4-one), and indenothiophenes.

  17. Synthesis and biological evaluation of kojic acid derivatives containing 1,2,4-triazole as potent tyrosinase inhibitors.

    Science.gov (United States)

    Xie, Wenlin; Zhang, Jingai; Ma, Xiaojing; Yang, Wenqian; Zhou, Ying; Tang, Xufu; Zou, Yan; Li, Hui; He, Jingjing; Xie, Shimin; Zhao, Yunhui; Liu, Fengping

    2015-11-01

    A series of 5-substituted-3-[5-hydroxy-4-pyrone-2-yl-methymercapto]-4-amino-1,2,4-triazole derivatives were synthesized by nucleophilic substitution reaction of 5-hydroxy-2-chloromethyl -4H-pyran-4-one with 5-substituted-3-mercapto-4-amino-1,2,4-triazole, and their inhibitory effects on mushroom tyrosinase were evaluated. The results indicated that most of the synthesized compounds exhibited significant inhibitory activity. Specifically, 5-(4-chlorophenyl)-3-[5-hydroxy-4-pyrone-2-yl-methymercapto]-4-amino-1,2,4-triazole (6j) exhibited the most potent tyrosinase inhibitory activity with IC50 value of 4.50 ± 0.34 μm. The kinetic studies of the compound (6j) demonstrated that the inhibitory effects of the compound on the tyrosinase were belonging to competitive inhibitors. Meanwhile, the structure-activity relationship was also discussed.

  18. The Structure-Function Relationships of Classical Cannabinoids: CB1/CB2 Modulation.

    Science.gov (United States)

    Bow, Eric W; Rimoldi, John M

    2016-01-01

    The cannabinoids are members of a deceptively simple class of terpenophenolic secondary metabolites isolated from Cannabis sativa highlighted by (-)-Δ(9)-tetrahydrocannabinol (THC), eliciting distinct pharmacological effects mediated largely by cannabinoid receptor (CB1 or CB2) signaling. Since the initial discovery of THC and related cannabinoids, synthetic and semisynthetic classical cannabinoid analogs have been evaluated to help define receptor binding modes and structure-CB1/CB2 functional activity relationships. This perspective will examine the classical cannabinoids, with particular emphasis on the structure-activity relationship of five regions: C3 side chain, phenolic hydroxyl, aromatic A-ring, pyran B-ring, and cyclohexenyl C-ring. Cumulative structure-activity relationship studies to date have helped define the critical structural elements required for potency and selectivity toward CB1 and CB2 and, more importantly, ushered the discovery and development of contemporary nonclassical cannabinoid modulators with enhanced physicochemical and pharmacological profiles.

  19. Structure-Based Design of Inhibitors Against Maltosyltransferase Glge

    Directory of Open Access Journals (Sweden)

    Junie B. Billones

    2014-09-01

    Full Text Available The emergence of Mycobacterium tuberculosis(Mtb drug resistant strains calls for research of novel anti-TB drugs. In this study,structure-based pharmacophore generation, virtual screening, molecular docking and de novolead optimization were employed in the search for possible inhibitors of MaltosyltransferaseGlgE enzyme,a recently validated anti-TB drug target. Chemical libraries containing only natural products were screened. The top hits were docked and the resulting leads were subsequently modified usingDe Novo Evolution. Three modified compounds were found to have greaterbinding energy than the substrate. All were derived from the lead compound ZINC39010596 (5,7-dihydroxy-2-propan-2-yl-8-[(2S,3R,4S,5S,6R-3,4,5-trihydroxy-6-(hydroxymethyltetrahydro-2H-pyran-2-yl]oxychromen-4-one. Toxicity predictions of these compounds revealed that they were non-carcinogenic, non-mutagenic, and biodegradable.

  20. Study on the interaction between different solute molecules in a molecular beam produced by the spray-jet technique: an application to dendrimer/dye system

    Science.gov (United States)

    Yamada, Toshiki; Ge, Maofa; Shinohara, Hidenori; Kimura, Katsumi; Mashiko, Shinro

    2003-10-01

    We report on an investigation into the interaction between different neutral non-volatile solute molecules in a molecular beam produced by the spray-jet technique that enables us to produce a molecular beam from a sprayed mist of a sample solution. This technique is applied to poly(propylene imine) dendrimer and 4-dicyanomethylene-2-methyl-6- p-dimethylaminostyryl-4H-pyran (DCM) systems. Resonantly enhanced multiphoton ionization of DCM in the DCM/dendrimer molecular beam leads to an efficient reaction between the dendrimer and DCM. The REMPI excitation spectra provide insights into the interaction between DCM and dendrimer molecules in the gas phase for the first time in these experiments.

  1. The Structure–Function Relationships of Classical Cannabinoids: CB1/CB2 Modulation

    Science.gov (United States)

    Bow, Eric W.; Rimoldi, John M.

    2016-01-01

    The cannabinoids are members of a deceptively simple class of terpenophenolic secondary metabolites isolated from Cannabis sativa highlighted by (−)-Δ9-tetrahydrocannabinol (THC), eliciting distinct pharmacological effects mediated largely by cannabinoid receptor (CB1 or CB2) signaling. Since the initial discovery of THC and related cannabinoids, synthetic and semisynthetic classical cannabinoid analogs have been evaluated to help define receptor binding modes and structure–CB1/CB2 functional activity relationships. This perspective will examine the classical cannabinoids, with particular emphasis on the structure–activity relationship of five regions: C3 side chain, phenolic hydroxyl, aromatic A-ring, pyran B-ring, and cyclohexenyl C-ring. Cumulative structure–activity relationship studies to date have helped define the critical structural elements required for potency and selectivity toward CB1 and CB2 and, more importantly, ushered the discovery and development of contemporary nonclassical cannabinoid modulators with enhanced physicochemical and pharmacological profiles. PMID:27398024

  2. Biosynthesis of pyranonaphthoquinone polyketides reveals diverse strategies for enzymatic carbon-carbon bond formation.

    Science.gov (United States)

    Metsä-Ketelä, Mikko; Oja, Terhi; Taguchi, Takaaki; Okamoto, Susumu; Ichinose, Koji

    2013-08-01

    Pyranonaphthoquinones synthesized by Streptomyces bacteria via type II polyketide pathways are aromatic compounds build around a common three-ring structure, which is composed of pyran, quinone and benzene rings. Over the years, actinorhodin in particular has served as a model compound for studying the biosynthesis of aromatic polyketides, while some of the other metabolites such as granaticin, medermycin, frenolicin and alnumycin A have enabled comparative studies that complement our understanding how these complex biological systems function and have evolved. In addition, despite the similarity of the aglycone units, pyranonaphthoquinones in effect display remarkable diversity in tailoring reactions, which include numerous enzymatic carbon-carbon bond forming reactions. This review focuses on the current status of molecular genetic, biochemical and structural investigations on this intriguing family of natural products.

  3. Catecholase activity investigations using in situ copper complexes continuing Schiff base derivatives with a theoretical calculation

    Directory of Open Access Journals (Sweden)

    A. Djedouani

    2015-03-01

    Full Text Available The study of catecholase activity of a series of Schiff base compounds using in situ copper complexes of 4-hydroxy-6-methyl-3-(1-(phenyliminoethyl-2H-pyran-2-one derivatives has been reported. The reaction rate depends on four parameters: The nature of the substitution in para position to the benzene ring, the nature of counter anion, the concentration of ligand and the nature of solvent. The highest rate activity is given by complex resulting from one equivalent of ligand L2 and two equivalents of copper acetate in methanol, which equal to 62.25 µmol.min-1.L-1.In other part, a theoretical study of such ligands using the semi-empirical method AM1 were also investigated. A good relationship founded between the maximal reaction rate (Vmax and the HOMO energy (Pearson correlation: r=-0.794.

  4. Fourier transform two-dimensional fluorescence excitation spectrometer by using tandem Fabry-Pérot interferometer.

    Science.gov (United States)

    Anzai, Hiroshi; Joshi, Neeraj Kumar; Fuyuki, Masanori; Wada, Akihide

    2015-01-01

    A Fourier transform two-dimensional fluorescence excitation spectrometer (FT-2DFES) was developed based on the multiplex technique using a tandem Fabry-Pérot interferometer (tandem FPI). In addition to the advantage of the multiplex technique, the main advantage of the tandem FPI is applicable to the modulation of transition with a large absorption bandwidth (larger than 100 nm) and is thus applicable to the modulation of the excitation of molecules in the condensed phase. As a demonstration of the effectiveness of FT-2DFES, we succeeded in separately observing the fluorescence excitation peaks from a mixed methanol solution of laser dyes (coumarin 480, rhodamine 6G, DCM (4-dicyanomethylene-2-methyl-6-(p-(dimethylamino)styryl)-4H-pyran), and LDS750). Furthermore, the energy transfer from rhodamine 6G to LDS750 was observed.

  5. Manipulation of spontaneous emission dynamics of organic dyes in the porous silicon matrix.

    Science.gov (United States)

    Makhal, Abhinandan; Kumar, Pushpendra; Lemmens, Peter; Pal, Samir Kumar

    2010-01-01

    The control of the spontaneous emission (SE) rate of dye molecules (4-dicyanomethylene-2-methyl-6-p-dimethylaminostyryl-4H-pyran (DCM) and Coumarin 523 (C523)) embedded in the Porous Silicon (PS) matrix has been studied using picosecond resolved fluorescence decay and polarization studies. We have shown that the SE rates of the two organic dyes embedded in the PS matrix depend on the relative positions of the emission maxima of the dyes with respect to electronic band gap energy of the PS matrix. We have also explored that the electronic band gap of the host PS matrix can easily be tuned by partial oxidation of the PS and the nature of SE of the embedded dyes can be tuned accordingly. The demonstrated retardation or enhancement of the spontaneous photon emission may enable the application of fluorescent organic molecules in PS matrix in several quantum optical devices including the realization of single photon sources.

  6. Improved Carrier Transfer in Red Organic Light Emitting Diodes Doped with Rubrene

    Institute of Scientific and Technical Information of China (English)

    刘宏宇; 高文宝; 杨开霞; 刘式墉

    2002-01-01

    A red organic light emitting diode doped with rubrene is constructed with the configuration of ITO/NPB/Alq3:rubrene:DCM/Alq3/LiF/Al. In the device, N,N'-bis-(1-naphthl)-N,N:diphenyl-1,1'-biphenyl-4,4'-diamine (NPB) is used as the hole-transporting layer, tris(8-quinolinolato) aluminium (Alq3) as the electron-transporting layer and Alq3 doped with 5,6,11,12-tetraphenylnaphthacene (rubrene) and 4-dicyanomethylene-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran (DCM) as the emitting layer. When the doping concentration of rubrene is 6% and that of DCM is 4%, red purity of the device is improved effectively. The experimental phenomena are explained as the result of the improved carrier transfer from rubrene to DCM.

  7. The Influence of Oxygen Atoms on Conformation and π-π Stacking of Ladder-Type Donor-Based Polymers and Their Photovoltaic Properties.

    Science.gov (United States)

    Qin, Tong; Zang, Yue; Bai, Wei-Yun; Yao, Kai; Xu, Yun-Xiang

    2017-08-01

    A novel ladder-type donor pyran-bridged indacenodithiophene (IDTP) is developed by introducing two oxygen atoms into indacenodithiophene unit. IDTP possesses a twisted backbone and leads to facially asymmetric arrangement of side chains, resulting in enhanced local π-π stacking of according polymer poly[(5,5,11,11-tetrakis(4-octylphenyl)-5,11-dihydrothieno[2',3':5,6]pyrano[3,4-g]thieno[3,2-c]isochromene)-alt-4,7-(5-fluoro-2,1,3-benzothiadiazole)] (PIDTP)-FBT, which shows extended absorption range. Moreover, oxygen atoms render deeper highest occupied molecular orbital (HOMO) levels of poly[indacenodithiophene-alt-4,7-(5-fluoro-2,1,3-benzothiadiazole)] (PIDTP)-FBT compared with PIDT-FBT, therefore bringing a higher open-circuit voltage (Voc ). © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. The isolation and antioxidant activity of polysaccharides from the marine microalgae Isochrysis galbana.

    Science.gov (United States)

    Sun, Yingying; Wang, Hui; Guo, Ganlin; Pu, Yinfang; Yan, Binlun

    2014-11-26

    Three polysaccharides, IPSI-A, IPSI-B and IPSII, were successfully isolated from the marine microalgae Isochrysis galbana through a combination of anion-exchange column chromatography and repeated gel chromatography. These three polysaccharides were demonstrated to have moderate scavenging activities against superoxide and hydroxyl radicals and moderate reductive power in a concentration-dependent manner. The IPSII demonstrated more effective antioxidant activities than IPSI-A and IPSI-B. IPSII had a molecular weight of 15.934 kDa belonging to a β-type heteropolysaccharide with a pyran group and primarily contained mannose with variable amounts of glucose, galactose and rhamnose based on an analysis of infrared spectroscopy (IR), electrospray ionization-mass spectrometry (ESI-MS) and (1)H nuclear magnetic resonance ((1)H NMR).

  9. Anti-TMV activity flavones from the leaves of Yunnan local air cured tobacco.

    Science.gov (United States)

    Miao, Ming-Ming; Li, Lan; Shen, Qin-Peng; Liu, Chun-Bo; Li, Yin-Ke; Zhang, Tao; Zhang, Feng-Mei; He, Pei; Wang, Kun-Miao; Zhu, Rui-Zhi; Chen, Yong-Kuan; Yang, Guang-Yu

    2015-06-01

    Four new flavones, tobaflavones E-H (1-4), together with two known flavones (5 and 6), were isolated from the leaves of Dali Tiandeng tobacco (a variety of Yunnan local air cured tobacco). Their structures were elucidated by spectroscopic methods, including extensive 1D- and 2D NMR techniques. Compound 2 is the first naturally occurring flavone bearing a (4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)methyl moiety. These compounds were also evaluated for their anti-tobacco mosaic virus (anti-TMV) activity. The results revealed that compounds 1 and 2 exhibited high anti-TMV activity with inhibition rate of 35.3% and 39.6%, respectively. The rates are higher than those of positive control. The other compounds also showed potential anti-TMV activity with inhibition rates in the range of 18.7-28.4%, respectively. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. A new methodology capable of characterizing most volatile and less volatile minor edible oils components in a single chromatographic run without solvents or reagents. Detection of new components.

    Science.gov (United States)

    Alberdi-Cedeño, Jon; Ibargoitia, María L; Cristillo, Giovanna; Sopelana, Patricia; Guillén, María D

    2017-04-15

    The possibilities offered by a new methodology to determine minor components in edible oils are described. This is based on immersion of a solid-phase microextraction fiber of PDMS/DVB into the oil matrix, followed by Gas Chromatography/Mass Spectrometry. It enables characterization and differentiation of edible oils in a simple way, without either solvents or sample modification. This methodology allows simultaneous identification and quantification of sterols, tocols, hydrocarbons of different natures, fatty acids, esters, monoglycerides, fatty amides, aldehydes, ketones, alcohols, epoxides, furans, pyrans and terpenic oxygenated derivatives. The broad information provided by this methodology is useful for different areas of interest such as nutritional value, oxidative stability, technological performance, quality, processing, safety and even the prevention of fraudulent practices. Furthermore, for the first time, certain fatty amides, gamma- and delta-lactones of high molecular weight, and other aromatic compounds such as some esters derived from cinnamic acid have been detected in edible oils.

  11. Microwave-assisted synthesis and tyrosinase inhibitory activity of chalcone derivatives.

    Science.gov (United States)

    Liu, Jinbing; Chen, Changhong; Wu, Fengyan; Zhao, Liangzhong

    2013-07-01

    A series of chalcones and their derivatives were synthesized, and their inhibitory effects on the diphenolase activity of mushroom tyrosinase were evaluated. The results showed that some of the synthesized compounds exhibited significant inhibitory activity, and four compounds exhibited more potent tyrosinase inhibitory activity than the reference standard inhibitor kojic acid (5-hydroxy-2-(hydroxymethyl)-4H-pyran-4-one). Specifically, 1-(-1-(4-methoxyphen- yl)-3-phenylallylidene)thiosemicarbazide (18) exhibited the most potent tyrosinase inhibitory activity with IC₅₀ value of 0.274 μM. The inhibition mechanism analysis of 1-(-1-(2,4-dihydroxyphenyl)-3-phenylallylidene) thiosemicarbazide (16) and 1-(-1-(4-methoxyphenyl)-3-phenylallylidene) thiosemicarbazide (18) demonstrated that the inhibitory effects of the two compounds on the tyrosinase were irreversible. Preliminary structure activity relationships' analysis suggested that further development of such compounds might be of interest.

  12. 3,5,7-Trimethoxy-2-(4-methoxyphenyl-4H-1-benzopyran-4-one

    Directory of Open Access Journals (Sweden)

    Thammarat Aree

    2009-11-01

    Full Text Available In the title compound, C19H18O6, also known as 3,4′,5,7-tetramethoxyflavone, the dihedral angle between the benzopyran-4-one group and the attached benzene ring is 11.23 (8°. An intramolecular C—H...O hydrogen bond generates an S(6 ring motif. In the crystal, molecules are linked into a two-dimensional network parallel to (0overline{1}1 by intermolecular C—H...O hydrogen bonds, which generate R44(20, R44(12 and R22(14 ring motifs. Adjacent networks interact by π–π interactions between the pyran ring and its methoxyphenyl substituent [centroid–centroid distance = 3.5267 (8 Å].

  13. A new diketopiperazine heterodimer from an endophytic fungus Aspergillus niger.

    Science.gov (United States)

    Li, Xiao-Bin; Li, Yue-Lan; Zhou, Jin-Chuan; Yuan, Hui-Qing; Wang, Xiao-Ning; Lou, Hong-Xiang

    2015-01-01

    One new diketopiperazine heterodimer, asperazine A (1), and eight known compounds, asperazine (2), cyclo(d-Phe-l-Trp) (3), cyclo(l-Trp-l-Trp) (4), 4-(hydroxymethyl)-5,6-dihydro-pyran-2-one (5), walterolactone A (6), and campyrones A-C (7-9), were isolated from an endophytic fungus Aspergillus niger. Their structures were determined unequivocally on the basis of extensive spectroscopic data analysis. This is the first report of the presence of compound 3 as a natural product. Cytotoxicity test against human cancer cell lines PC3, A2780, K562, MBA-MD-231, and NCI-H1688 revealed that compounds 1 and 2 had weak activities.

  14. A Novel Schiff Base of 3-acetyl-4-hydroxy-6-methyl-(2Hpyran-2-one and 2,2'-(ethylenedioxydiethylamine as Potential Corrosion Inhibitor for Mild Steel in Acidic Medium

    Directory of Open Access Journals (Sweden)

    Jonnie N. Asegbeloyin

    2015-05-01

    Full Text Available The corrosion inhibition activity of a newly synthesized Schiff base (SB from 3-acetyl-4-hydroxy-6-methyl-(2H-pyran-2-one and 2,2'-(ethylenedioxydiethylamine was investigated on the corrosion of mild steel in 1 M HCl solution using potentiodynamic polarization and electrochemical impedance spectroscopic techniques. Ultraviolet-visible (UV-vis and Raman spectroscopic techniques were used to study the chemical interactions between SB and mild steel surface. SB was found to be a relatively good inhibitor of mild steel corrosion in 1 M HCl. The inhibition efficiency increases with increase in concentration of SB. The inhibition activity of SB was ascribed to its adsorption onto mild steel surface, through physisorption and chemisorption, and described by the Langmuir adsorption model. Quantum chemical calculations indicated the presence of atomic sites with potential nucleophilic and electrophilic characteristics with which SB can establish electronic interactions with the charged mild steel surface.

  15. Assignment of the absolute configuration of (+)-diplopyrone, the main phytotoxin produced by Diplodia mutila, the pathogen of the cork oak decline, by a nonempirical analysis of its chiroptical properties.

    Science.gov (United States)

    Giorgio, Egidio; Maddau, Lucia; Spanu, Emanuela; Evidente, Antonio; Rosini, Carlo

    2005-01-07

    The nonempirical assignment of the absolute configuration of (+)-diplopyrone, the main phytotoxin of Diplodia mutila, i.e., an endophytic fungus, widespread in Sardinian oak forests, and considered one of the main causes of cork oak decline, has been approached by two different methods: (a) the exciton analysis of the circular dichroism (CD) spectrum and (b) the ab initio calculation of the optical rotatory power. Both methods indicate that (+)-diplopyrone is 6-[(1S)-1-hydroxyethyl]-2,4a(S),6(R),8a(S)-tetrahydropyrano[3,2-b]pyran-2-one, so the stereostructure of this important biomolecule is safely determined for the first time. A comparison of advantages and limitations of the two methods of analysis is also presented.

  16. Biscopyran, a phytotoxic hexasubstituted pyranopyran produced by Biscogniauxia mediterranea, a fungus pathogen of cork oak.

    Science.gov (United States)

    Evidente, Antonio; Andolfi, Anna; Maddau, Lucia; Franceschini, Antonio; Marras, Francesco

    2005-04-01

    A new phytotoxic hexasubstituted pyranopyran, biscopyran (3), was isolated together with phenylacetic acid (2) and previously isolated 5-methylmellein (1) from the liquid culture filtrates of Biscogniauxiamediterranea, a major fungal pathogen involved in oak decline in Sardinia. Biscopyran was characterized by spectroscopic methods as a new (Z)-2-methoxy-1-[7-((Z)-2-methoxybut-2-enoyl)-3,4,5,6-tetramethyl-2H,7H-pyrano[2,3-b]pyran-2-yl]but-2-en-1-one. Biscopyran assayed at 0.26-0.026 mM concentration range caused epinasty on cork oak cuttings. On a nonhost plant, tomato, biscopyran caused wilting. Phenylacetic acid, assayed at the same concentration, was toxic to Q. suber, while on tomato cuttings it induced internal tissue collapse on the stem.

  17. Diplopyrone, a new phytotoxic tetrahydropyranpyran-2-one produced by Diplodia mutila, a fungus pathogen of cork oak.

    Science.gov (United States)

    Evidente, Antonio; Maddau, Lucia; Spanu, Emanuela; Franceschini, Antonio; Lazzaroni, Silvia; Motta, Andrea

    2003-02-01

    A new phytotoxic monosubstituted tetrahydropyranpyran-2-one, named diplopyrone (1), was isolated from the liquid culture filtrates of Diplodia mutila, a plant pathogenic fungus causing a form of canker disease of cork oak (Quercus suber). Diplopyrone was characterized, using spectroscopic and chemical methods, as 6-[(1S)-1-hydroxyethyl]-2,4a,6,8a-tetrahydropyran[3,2-b]pyran-2-one. The absolute stereochemistry of the chiral secondary hydroxylated carbon (C-9), determined by application of Mosher's method, proved to be S. Diplopyrone assayed at a 0.01-0.1 mg/mL concentration range caused necrosis and wilting on cork oak cuttings. On a nonhost plant, tomato, diplopyrone caused brown discoloration or stewing on the stem.

  18. 7-Chloro-4-oxo-4H-chromene-3-carbaldehyde

    Directory of Open Access Journals (Sweden)

    Yoshinobu Ishikawa

    2014-08-01

    Full Text Available In the title compound, C10H5ClO3, a chlorinated 3-formylchromone derivative, all atoms are essentially coplanar (r.m.s. deviation = 0.0592 Å for all non-H atoms, with the largest deviation from the least-squares plane [0.1792 (19 Å] being for the chromone-ring carbonyl O atom. In the crystal, molecules are linked through C—H...O hydrogen bonds to form tetrads, which are assembled by stacking interactions [centroid–centroid distance between the pyran rings = 3.823 (3 Å] and van der Waals contacts between the Cl atoms [Cl...Cl = 3.4483 (16 Å and C—Cl...Cl = 171.73 (7°] into a three-dimensional architecture.

  19. Spectral assignments and structural studies of a warfarin derivative stereoselectively formed by tandem cyclization

    Science.gov (United States)

    Velayutham Pillai, M.; Rajeswari, K.; Vidhyasagar, T.

    2015-11-01

    The structural elucidation of a Mannich condensation product of rac-Warfarin with benzaldehyde and methyl amine was carried out using IR, Mass, 1H NMR, 13C NMR, 1H-1H COSY, 1H-13C COSY, DEPT-135, HMBC, NOESY spectra and single crystal X-ray diffraction. Formation of a new pyran ring via a tandem cyclization in the presence of methyl amine was observed. The optimized geometry and HOMO-LUMO energy gap along with other important physical parameters were found by Gaussian 09 program using HF 6-31G (d, p) and B3YLP/DFT 6-31G (d, p) level of theory. The preferred conformation of the piperidine ring in solution state was found to be chair from the NMR spectra. Single crystal X-ray diffraction and optimized geometry (by theoretical study) also confirms the chair conformation in the solid state.

  20. 2D-NMR, X-ray crystallography and theoretical studies of the reaction mechanism for the synthesis of 1,5-benzodiazepines from dehydroacetic acid derivatives and o-phenylenediamines

    Science.gov (United States)

    Rabahi, Amal; Hamdi, Safouane M.; Rachedi, Yahia; Hamdi, Maamar; Talhi, Oualid; Almeida Paz, Filipe A.; Silva, Artur S. M.; Fadila, Balegroune; Malika, Hamadène; Kamel, Taïbi

    2014-03-01

    The synthesis of 1,5-benzodiazepines by the reaction of o-phenylenediamines (o-PDAs) with dehydroacetic acid DHAA [3-acetyl-4-hydroxy-6-methyl-2H-pyran-2-one] or conjugate analogues is largely reported in the literature, but still with uncontrolled stereochemistry. In this work, a comprehensive mechanistic study on the formation of some synthesized 1,5-benzodiazepine models following different organic routes is established based on liquid-state 2D NMR, single-crystal X-ray diffraction and theoretical calculations allowing the classification of two prototropic forms A (enaminopyran-2,4-dione) and B (imino-4-hydroxypyran-2-one). Evidences are presented to show that most of the reported 1,5-benzodiazepine structures arising from DHAA and derivatives preferentially adopt the (E)-enaminopyran-2,4-diones A.

  1. Screen-printed photochromic textiles through new inks based on SiO2@naphthopyran nanoparticles.

    Science.gov (United States)

    Pinto, Tânia V; Costa, Paula; Sousa, Céu M; Sousa, Carlos A D; Pereira, Clara; Silva, Carla J S M; Pereira, Manuel Fernando R; Coelho, Paulo J; Freire, Cristina

    2016-10-05

    Photochromic silica nanoparticles (SiO2@NPT), fabricated through covalent immobilization of silylated naphthopyrans based on 2H-naphtho[1,2-b]pyran (S1, S2) and 3H-naphtho[2,1-b]pyran (S3, S4) or through direct adsorption of parent naphthopyrans (NPT 1, 3) onto silica nanoparticles, were successfully incorporated onto cotton fabrics by screen-printing process. Two aqueous acrylic (AC) and polyurethane (PU)-based inks were used as dispersing media. All textiles exhibited reversible photochromism under UV and solar irradiation, developing fast response and intense coloration. The fabrics coated with SiO2@S1 and SiO2@S2 showed a rapid color change and high contrast (ΔE*ab = 39-52), despite presenting slower bleaching kinetics (2-3 h to fade to the original color), whereas the textiles coated with SiO2@S3 and SiO2@S4 exhibited an excellent engagement between coloration and decoloration rates (coloration and fading times of 1 and 2 min, respectively; ΔE*ab = 27-53). The PU-based fabrics showed excellent results during the washing fastness tests, while the AC-based textiles only evidenced good results when a protective transfer film was applied over the printed design. In general, all textiles presented high color contrast, high photostability (during continuous UV irradiation) and stable photochromic responses upon twelve successive UV light/dark cycles, becoming excellent alternatives to other photochromic textiles reported in the literature.

  2. Novel mechanisms of biotransformation of p-tert-amylphenol by bacteria and fungi with special degradation abilities and simultaneous detoxification of the disinfectant.

    Science.gov (United States)

    Schlueter, Rabea; Röder, Anja; Czekalski, Nadine; Gliesche, Daniel; Mikolasch, Annett; Schauer, Frieder

    2014-01-01

    The compound p-tert-amylphenol (p-(1,1-dimethylpropyl)phenol) is a widely used disinfectant belonging to the group of short branched-chain alkylphenols. It is produced in or imported into the USA with more than one million pounds per year and can be found in the environment in surface water, sediments, and soil. We have investigated for the first time the biotransformation of this disinfectant and the accumulation of metabolites by five bacterial strains, three yeast strains, and three filamentous fungi, selected because of their ability to transform either aromatic or branched-chain compounds. Of the 11 microorganisms tested, one yeast strain and three bacteria could not transform the disinfectant despite of a very low concentration applied (0.005%). None of the other seven organisms was able to degrade the short branched alkyl chain of p-tert-amylphenol. However, two yeast strains, two filamentous fungi, and two bacterial strains attacked the aromatic ring system of the disinfectant via the hydroxylated intermediate 4-(1,1-dimethyl-propyl)-benzene-1,2-diol resulting in two hitherto unknown ring fission products with pyran and furan structures, 4-(1,1-dimethyl-propyl)-6-oxo-6-H-pyran-2-carboxylic acid and 2-[3-(1,1-dimethyl-propyl)-5-oxo-2H-furan-2-yl]acetic acid. While the disinfectant was toxic to the organisms applied, one of the ring cleavage products was not. Thus, a detoxification of the disinfectant was achieved by ring cleavage. Furthermore, one filamentous fungus formed sugar conjugates with p-tert-amylphenol as another mechanism of detoxification of toxic environmental pollutants. With this work, we can also contribute to the allocation of unknown chemical compounds within environmental samples to their parent compounds.

  3. Study on chemical composition of ethylacetate fraction from Bolbostemma paniculatum (Maxim.) Franquet%藤贝母乙酸乙酯部位化学成分研究

    Institute of Scientific and Technical Information of China (English)

    何峰; 向梅先; 胡亚京; 刘新桥

    2015-01-01

    采用薄层色谱、正相硅胶柱、反向硅胶柱、葡聚糖凝胶、半制备高效液相柱对植物药藤贝母乙酸乙酯部位的化学成分进行了系统的研究.共分离得到8个单体化合物,分别为:7-羟基-6-甲氧基香豆素(7-hydroxy-6-methoxy coumarin) (1),表儿茶素(epicatechin) (2),儿茶素(catechin) (3),(E)-N-(4-羟基苯乙基)-3-(4-羟基-3-甲氧基苯基)丙烯酰胺[(E)-N hydroxy phenyl ethyl-3-(4-hydroxy-3-methoxy phenyl) acrylamide] (4),邻苯二甲酸二丁酯(Dibutyl phthalate) (5),(Z)-3-O-咖啡酰基-4-0-甲基奎宁酸甲酯[(Z)-3-O-Coffee acyl-4-O-methyl quinic acid methyl ester] (6),绿原酸甲酯(methyl chlorogenate) (7),3-O-[β-D-吡喃鼠李糖-(1-6)-β-D-吡喃半乳糖]-5,7,4'-三羟基黄酮(3-0-[beta-D-pyran rhamnose-(1-6)-beta-D-pyran galactose]-5,7,4'-three hydroxy flavone)(8).所有化合物均首次从该植物分离得到.

  4. Identification of urolithin a as a metabolite produced by human colon microflora from ellagic acid and related compounds.

    Science.gov (United States)

    Cerdá, Begoña; Periago, Paula; Espín, Juan Carlos; Tomás-Barberán, Francisco A

    2005-07-13

    Dietary ellagic acid and related polyphenols are metabolized in humans to dibenzopyran-6-one derivatives, and the microbial origin of these metabolites has been suggested. However, this has not been demonstrated so far. Fecal samples donated by six volunteers were incubated under anaerobic conditions, and aliquots were used to evaluate the fecal metabolism of ellagic acid, the ellagitannin punicalagin, and an ellagitannin rich extract from walnuts. The isoflavone daidzein was also incubated with the same fecal samples to follow the production of the microbial metabolites previously reported (dihydrogenistein, O-demethylangolensin, and equol) as a positive control of the system and to evaluate similarities between isoflavone and ellagic acid fecal flora metabolism. After fermentation the metabolite "urolithin A" (3,8-dihydroxy-6H-dibenzo[b,d]pyran-6-one) was produced from ellagic acid, punicalagin, and the ellagitannin extract in all the fecal cultures from different volunteers, but with very different production rates and concentrations. This large variability in the concentration of metabolite and kinetics of metabolite production is consistent with the large variability found in the excretion of these metabolites in urine in vivo after human consumption of ellagitannins, and with differences in the composition of the fecal microflora. No correlation between isoflavone and ellagic acid metabolism by fecal microflora was observed. The present study confirms the microbial origin of the recently reported in vivo generated hydroxy-6H-dibenzo[b,d]pyran-6-one derivatives in humans and is a further step in the study of the bioavailability and metabolism of ellagic acid and ellagitannins.

  5. Removal of aflatoxin M1 from artificially contaminated yoghurt by using of new synthesized dehydroacetic acid analogues

    Directory of Open Access Journals (Sweden)

    Frane Delaš

    2012-09-01

    Full Text Available Dehydroacetic acid (DHA and its new synthesized analogues, 4-hydroxy-3-(p-toluoyl-6-(ptolyl-2H-pyrane-2-one (DHT and 5-Bromo-4-hydroxy-3-(p-toluoyl-6-(p-tolyl-2H-pyrane-2-one (BrDHT were tested for removal of aflatoxin M1 (AFM1 from artificially contaminated yoghurt with known concentrations of this toxin to determine the possible use of these chemicals as a means of controlling AFM1 accumulation. Yoghurt from cow’s milk was artificially contaminated with AFM1 at levels of 0.01 to 0.5 μg/L. Yoghurts were stored at 4 °C and 7 °C, respectively, for up to 28 days. Analysis of AFM1 in yoghurt was carried out using two dimensional thin-layer chromatography (TLC - visual estimation. The limit of detection was 0.15 ng/L. The recoveries of AFM1 from the samples spiked at levels of 10, 50, 100, and 500 ng/L were between 80.6 and 107.8 %, respectively. Concentrations of DHA and DHT of 0.01 and 0.03 μmol/L had non or little effect on AFM1 content in experimentally contaminated yoghurt, whereas concentrations higher than 0.05 μmol/L, partially inhibited AFM1 content. The percentage loss of the initial AFM1 amount in yoghurt was estimated by about 15 and 25 %, and 22 to 45 % by the end of storage, respectively. In experiments with 0.01 and 0.05 μmol/L of BrDHT or higher, the concentration of AFM1 was reduced after 28 days by 20 to 95 % or completely, respectively, depending on the time and temperature of deposit. Detection of toxicity of investigated analogues was evaluated by using the brine shrimp (Artemia salina larvae as a screening system for the determination of their sensitivity to some chemicals

  6. Naphthopyran-Based Silica Nanoparticles as New High-Performance Photoresponsive Materials.

    Science.gov (United States)

    Pinto, Tânia V; Costa, Paula; Sousa, Céu M; Sousa, Carlos A D; Monteiro, Andreia; Pereira, Clara; Soares, Olívia Salomé G P; Silva, Carla S M; Pereira, Manuel Fernando R; Coelho, Paulo J; Freire, Cristina

    2016-03-23

    Hybrid nanomaterials based on the covalent grafting of silylated naphthopyrans (NPTs) onto silica nanoparticles (SiO2 NPs) were successfully prepared and studied as new photochromic materials. They were prepared by a two-step protocol consisting of (i) NPTs (derivatives from 2H-naphtho[1,2-b]pyran (2H-NPT) and 3H-naphtho[2,1-b]pyran (3H-NPT)) silylation by a microwave-assisted reaction between hydroxyl-substituted NPTs and 3-(triethoxysilyl)propyl isocyanate, followed by (ii) covalent post-grafting onto SiO2 NPs. In order to study the role of the silylation step, the analogous non-silylated nanomaterials were also prepared by direct adsorption of NPTs. The characterization techniques confirmed the successful NPTs silylation and subsequent grafting to SiO2 NPs. All SiO2-based nanomaterials revealed photoswitching behavior, following a biexponential decay. The SiO2 NPs functionalized with silylated 3H-NPTs (SiO2@S3 and SiO2@S4) presented the most promising photochromic properties, showing fast coloration/decoloration kinetics (coloring in 1 min under UV irradiation and fading in only 2 min) and high values of total color difference (ΔE*ab = 30-50). Also, the 2H-NPTs-based SiO2 NPs (SiO2@S1 and SiO2@S2) presented fast coloration and good color contrasts (ΔE*ab = 54), but slower fading kinetic rates, taking more than 2 h to return to their initial color. In contrast, the SiO2 NPs functionalized with non-silylated NPTs (SiO2@1 and SiO2@3) showed weaker color contrasts (ΔE*ab = 6-10) and slower fading kinetics, proving that the NPT silylation step was crucial to enhance the photochromic behavior of SiO2 NPs based on NPTs. Furthermore, the silylated-based nanomaterials showed good photostability upon prolonged UV light exposure, keeping their photochromic performance unchanged for at least 12 successive UV/dark cycles, anticipating interesting technological applications in several areas.

  7. SINTESIS SENYAWA C18H26O9 DARI HIPTOLIDA HASIL ISOLASI DAUN HYPTIS PECTINATA

    Directory of Open Access Journals (Sweden)

    Meiny Suzery

    2012-05-01

    Full Text Available SYNTHESIS OF C18H26O9 COMPOUNDS FROM HYPTOLIDE ISOLATED FROM HYPTIS PECTINATA LEAVES. Isolation of hyptolide has been done from Hyptis pectinata, and alkene group transformation through oxidation reactions using H3B: OEt2 to the isolated compound was also conducted. Product analyses were carried out using TLC, UV spectrometry, IR, and LC-MS. Pure crystal with melting point of 86-87oC was isolated. The yield was 1.75% (w/w. After analysing and compilating of spectroscopic data it was confirmed as hyptolide compound. Hydroboration of this compound (followed by hydrolysis using H2O2 under alkaline conditions produce its alcohol derivatives, with 28.9% the percentage of transformation, it was demonstrated by LCMS data. IR spectrum at 3600cm-1, confirming the replacement of hydroxyl bond by alkene. Regioselectivity of addition reaction is proposed through simulation with Chem Office. The reaction product was suspected as 6-hydroxy-7-(6-oxo-3,6-dihydro-2H-pyran-2-yl heptane-2,3,5-tryil triacetate. Extension of reaction time to 24 hours, has increase hydroboration product to 78.3%. This research has opened other studies of natural materials in accordance to the roadmap set.  Telah dilakukan isolasi hiptolida dari bahan alam Hyptis pectinata, dan transformasinya melalui reaksi oksidasi menggunakan H3B:OEt2 terhadap gugus alkena pada senyawa hasil isolasi. Analisis produk dilakukan menggunakan KLT, spektrometri UV, IR, dan LC-MS. Kristal murni dengan titik leleh 86-87oC berhasil diisolasi dengan rendemen 1,75 % (b/b, dirujuk sebagai senyawa hiptolida setelah melalui analisis dan kompilasi data-data spektroskopi. Hidroborasi terhadap senyawa hiptolida (yang diikuti hidrolisis menggunakan H2O2 dalam suasana basa menghasilkan senyawa alkohol turunannya, dengan persentase transformasi sebesar 28,9%, dapat ditunjukkan melalui data LCMS. Data spectrum IR menunjukkan adanya puncak pada 3600cm-1, memperkuat dugaan  adanya ikatan hidroksil menggantikan gugus

  8. Extension of the SAFT-VR Mie EoS To Model Homonuclear Rings and Its Parametrization Based on the Principle of Corresponding States.

    Science.gov (United States)

    Müller, Erich A; Mejía, Andrés

    2017-06-28

    The statistical associating fluid theory of variable range employing a Mie potential (SAFT-VR-Mie) proposed by Lafitte et al. (J. Chem Phys. 2013, 139, 154504) is one of the latest versions of the SAFT family. This particular version has been shown to have a remarkable capability to connect experimental determinations, theoretical calculations, and molecular simulations results. However, the theoretical development restricts the model to chains of beads connected in a linear fashion. In this work, the capabilities of the SAFT-VR Mie equation of state for modeling phase equilibria are extended for the case of planar ring compounds. This modification proposed replaces the Helmholtz energy of chain formation by an empirical contribution based on a parallelism to the second-order thermodynamic perturbation theory for hard sphere trimers. The proposed expression is given in terms of an extra parameter, χ, that depends on the number of beads, ms, and the geometry of the ring. The model is used to describe the phase equilibrium for planar ring compounds formed of Mie isotropic segments for the cases of ms equals to 3, 4, 5 (two configurations), and 7 (two configurations). The resulting molecular model is further parametrized, invoking a corresponding states principle resulting in sets of parameters that can be used indistinctively in theoretical calculations or in molecular simulations without any further refinements. The extent and performance of the methodology has been exemplified by predicting the phase equilibria and vapor pressure curves for aromatic hydrocarbons (benzene, hexafluorobenzene, toluene), heterocyclic molecules (2,5-dimethylfuran, sulfolane, tetrahydro-2H-pyran, tetrahydrofuran), and polycyclic aromatic hydrocarbons (naphthalene, pyrene, anthracene, pentacene, and coronene). An important aspect of the theory is that the parameters of the model can be used directly in molecular dynamics (MD) simulations to calculate equilibrium phase properties and

  9. Fungal Endophyte Diversity and Bioactivity in the Indian Medicinal Plant Ocimum sanctum Linn.

    Directory of Open Access Journals (Sweden)

    Kanika Chowdhary

    Full Text Available Endophytic mycopopulation isolated from India's Queen of herbs Tulsi (Ocimum sanctum were explored and investigated for their diversity and antiphytopathogenic activity against widespread plant pathogens Botrytis cinerea, Sclerotinia sclerotiorum, Rhizoctonia solani and Fusarium oxysporum. 90 fungal isolates, representing 17 genera were recovered from 313 disease-free and surface sterilised plant segments (leaf and stem tissues from three different geographic locations (Delhi, Hyderabad and Mukteshwar during distinct sampling times in consequent years 2010 and 2011 in India. Fungal endophytes were subjected to molecular identification based on rDNA ITS sequence analysis. Plant pathogens such as F. verticillioides, B. maydis, C. coarctatum, R. bataticola, Hypoxylon sp., Diaporthe phaseolorum, Alternaria tenuissima and A. alternata have occurred as endophyte only during second sampling (second sampling in 2011 in the present study. Bi-plot generated by principal component analysis suggested tissue specificity of certain fungal endophytes. Dendrogram revealed species abundance as a function of mean temperature of the location at the time of sampling. Shannon diversity in the first collection is highest in Hyderabad leaf tissues (H' = 1.907 whereas in second collection it was highest from leaf tissues of Delhi (H' = 1.846. Mukteshwar (altitude: 7500 feet reported least isolation rate in second collection. Nearly 23% of the total fungal isolates were considered as potent biocontrol agent. Hexane extract of M. phaseolina recovered from Hyderabad in first collection demonstrated highest activity against S. sclerotiorum with IC50 value of 0.38 mg/ml. Additionally, its components 2H-pyran-2-one, 5,6-dihydro-6-pentyl and palmitic acid, methyl ester as reported by GC-MS Chromatogram upon evaluation for their antiphytopathogenic activity exhibited IC50 value of 1.002 and 0.662 against respectively S. sclerotiorum indicating their significant role in

  10. (18)F-FBHGal for asialoglycoprotein receptor imaging in a hepatic fibrosis mouse model.

    Science.gov (United States)

    Kao, Hao-Wen; Chen, Chuan-Lin; Chang, Wen-Yi; Chen, Jenn-Tzong; Lin, Wuu-Jyh; Liu, Ren-Shyan; Wang, Hsin-Ell

    2013-02-15

    Quantification of the expression of asialoglycoprotein receptor (ASGPR), which is located on the hepatocyte membrane with high-affinity for galactose residues, can help assess ASGPR-related liver diseases. A hepatic fibrosis mouse model with lower asialoglycoprotein receptor expression was established by dimethylnitrosamine (DMN) administration. This study developed and demonstrated that 4-(18)F-fluoro-N-(6-((3,4,5-trihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-yl)oxy)hexyl)benzamide ((18)F-FBHGal), a new (18)F-labeled monovalent galactose derivative, is an asialoglycoprotein receptor (ASGPR)-specific PET probe in a normal and a hepatic fibrosis mouse models. Immunoassay exhibited a linear correlation between the accumulation of GalH-FITC, a fluorescent surrogate of FBHGal, and the amount of ASGPR. A significant reduction in HepG2 cellular uptake (P ASGPR blocking agent. Animal studies showed the accumulation of (18)F-FBHGal in fibrosis liver (14.84±1.10 %ID/g) was appreciably decreased compared with that in normal liver (20.50±1.51 %ID/g, P ASGPR-related liver dysfunction.

  11. Establishing a molecular relationship between chondritic and cometary organic solids.

    Science.gov (United States)

    Cody, George D; Heying, Emily; Alexander, Conel M O; Nittler, Larry R; Kilcoyne, A L David; Sandford, Scott A; Stroud, Rhonda M

    2011-11-29

    Multidimensional solid-state NMR spectroscopy is used to refine the identification and abundance determination of functional groups in insoluble organic matter (IOM) isolated from a carbonaceous chondrite (Murchison, CM2). It is shown that IOM is composed primarily of highly substituted single ring aromatics, substituted furan/pyran moieties, highly branched oxygenated aliphatics, and carbonyl groups. A pathway for producing an IOM-like molecular structure through formaldehyde polymerization is proposed and tested experimentally. Solid-state (13)C NMR analysis of aqueously altered formaldehyde polymer reveals considerable similarity with chondritic IOM. Carbon X-ray absorption near edge structure spectroscopy of formaldehyde polymer reveals the presence of similar functional groups across certain Comet 81P/Wild 2 organic solids, interplanetary dust particles, and primitive IOM. Variation in functional group concentration amongst these extraterrestrial materials is understood to be a result of various degrees of processing in the parent bodies, in space, during atmospheric entry, etc. These results support the hypothesis that chondritic IOM and cometary refractory organic solids are related chemically and likely were derived from formaldehyde polymer. The fine-scale morphology of formaldehyde polymer produced in the experiment reveals abundant nanospherules that are similar in size and shape to organic nanoglobules that are ubiquitous in primitive chondrites.

  12. Computational Insight to Improve the Thermal Isomerisation Performance of Overcrowded Alkene-Based Molecular Motors through Structural Redesign.

    Science.gov (United States)

    Oruganti, Baswanth; Wang, Jun; Durbeej, Bo

    2016-11-04

    Synthetic overcrowded alkene-based molecular motors achieve 360° unidirectional rotary motion of one motor half (rotator) relative to the other (stator) through sequential photochemical and thermal isomerisation steps. In order to facilitate and expand the use of these motors for various applications, it is important to investigate ways to increase the rates and efficiencies of the reactions governing the rotary motion. Here, we use computational methods to explore whether the thermal isomerisation performance of some of the fastest available motors of this type can be further improved by reducing the sizes of the motor halves. Presenting three new redesigned motors that combine an indanylidene rotator with a cyclohexadiene, pyran or thiopyran stator, we first use multiconfigurational quantum chemical methods to verify that the photoisomerisations of these motors sustain unidirectional rotary motion. Then, by performing density functional calculations, we identify both stepwise and concerted mechanisms for the thermal isomerisations of the motors and show that the rate-determining free-energy barriers of these processes are up to 25 kJ mol(-1) smaller than those of the original motors. Furthermore, the thermal isomerisations of the redesigned motors proceed in fewer steps. Altogether, the results suggest that the redesigned motors are useful templates for improving the thermal isomerisation performance of existing overcrowded alkene-based motors.

  13. Observation of Photovoltaic Effects in Bright Red Organic Electroluminescent Diodes Doped with Red Dopant

    Institute of Scientific and Technical Information of China (English)

    WEI Han-Zhi; Li Wen-Lian; WANG Dong-Yue; CHU Bei; Li Ming-Tao; ZHANG Zhi-Qiang; HU Zhi-Zhi

    2004-01-01

    @@ Photovoltaic (PV) effects for red bright organic light-emitting diodes (OLEDs) in which the red light emitted from the dopant 4-(dicyanomethylene)-2-t-butyl-6- (1,1,7, 7-tetramethyljulolidyl-9-enyl)-4H-pyran (DCJTB) have been observed. The OLEDs show organic photovoltaic properties. At the optimum doping concentration, the main eletroluminescence parameters including the maximum brightness and the maximum luminous efficiency under current density of 20mA/cm2 are 3280cd/m2 and 1.54cd/A, respectively. When irradiated by a 365-nm UVlight (4 mW/cm2), the device exhibits the PV parameters of the open-circuit voltage 1.4 V, short-circuit current 2.9 μA/cm2, fill factor 0.22, and power conversion efficiency 0.022%. Effects of every organic layer, especially the doped DCJTB on the PV performance, are also discussed. It is expected that the research for the PV property of the small molecular doping OLEDs will be of benefit for flat panel display technology in the future.

  14. Hydrogen-bonded structures and interaction energies in two forms of the SGLT-2 inhibitor sotagliflozin.

    Science.gov (United States)

    Gelbrich, Thomas; Adamer, Verena; Stefinovic, Marijan; Thaler, Andrea; Griesser, Ulrich J

    2017-09-01

    The sotagliflozin molecule exhibits two fundamentally different molecular conformations in form 1 {systematic name: (2S,3R,4R,5S,6R)-2-[4-chloro-3-(4-ethoxybenzyl)phenyl]-6-(methylsulfanyl)tetrahydro-2H-pyran-3,4,5-triol, C21H25ClO5S, (I)} and the monohydrate [C21H25ClO5S·H2O, (II)]. Both crystals display hydrogen-bonded layers formed by intermolecular interactions which involve the three -OH groups of the xyloside fragment of the molecule. The layer architectures of (I) and (II) contain a non-hydrogen-bonded molecule-molecule interaction along the short crystallographic axis (a axis) whose total PIXEL energy exceeds that of each hydrogen-bonded molecule-molecule pair. The hydrogen-bonded layer of (I) has the topology of the 4-connected sql net and that formed by the water and sotagliflozin molecules of (II) has the topology of a 3,7-connected net.

  15. Crystal structure of canagliflozin hemihydrate

    Directory of Open Access Journals (Sweden)

    Kai-Hang Liu

    2016-05-01

    Full Text Available There are two canagliflozin molecules (A and B and one water molecule in the asymmetric unit of the title compound, C24H25FO5S·0.5H2O [systematic name: (2S,3R,4R,5S,6R-2-(3-{[5-(4-fluorophenylthiophen-2-yl]methyl}-4-methylphenyl-6-(hydroxymethyl-3,4,5,6-tetrahydro-2H-pyran-3,4,5-triol hemihydrate]. The dihedral angles between the methylbenzene and thiophene rings are 115.7 (4 and 111.7 (4°, while the dihedral angles between the fluorobenzene and thiophene rings are 24.2 (6 and 20.5 (9° in molecules A and B, respectively. The hydropyran ring exhibits a chair conformation in both canagliflozin molecules. In the crystal, the canagliflozin molecules and lattice water molecules are connected via O—H...O hydrogen bonds into a three-dimensional supramolecular architecture.

  16. Interaction between {beta}-Lapachone and Ionizing Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Eun Kyung; Song, Si Yeol; Shin, Seong Soo; Lee, Sang Wook; Ahn, Seung Do; Kim, Jong Hoon [College of Medicine, University of Ulsan, Seoul (Korea, Republic of); Park, Heon Joo [College of Medicine, Inha University, Incheon (Korea, Republic of); Song, Chang Won [University of Minnesota Medical School, Minneapolis (United States)

    2006-07-01

    {beta}-Lapachone (3,4-dihydro-2,2-dimethyl-2Hnaphtho[ 1,2-b]pyran-5,6-dione)({beta}-lap) was originally isolated from the bark of the Lapacho tree growing in South America (1). This drug has attracted considerable interest in recent years because of its potent cytotoxicity against various cancer cell lines through a mechanism that works independent of the cell cycle of p53 status. Interestingly, {beta}-lap has been reported to react synergistically with Taxol, mitomycin C, genistein, and ionizing radiation (IR) (2-3) in vitro against cultured cancer cells. It has also been reported that {beta}-lap inhibits the repair of potentially lethal radiation damage by converting repairable single-stranded DNA breaks into repair-resistant, double-stranded DNA breaks. Thus {beta}- lap has been thought to act as a radiation sensitizer by inhibiting DNA damage repair. In the present study, we observed that IR sensitizes cancer cells to {beta}-lap. It thus appeared that the synergistic interaction of IR and {beta}-lap in killing cancer cells was due to an increase in cellular susceptibility to {beta}-lap, probably in addition to {beta}-lap. induced radiosensitization.

  17. Schiff base: A high affinity chemical agent to decrease the concentration of aflatoxin M1 in raw milk contaminated artificially

    Directory of Open Access Journals (Sweden)

    Frane Delaš

    2012-03-01

    Full Text Available In the present study were conducted the effect of pH (5.5, 6.0 and 6.5 and concentration of new synthesized 3-/2-aminophenylimino-(p-toluoyl/-4-hydroxy-6-(p-tolyl-2H-pyrane-2-one (Schiff base on decrease the concentration of aflatoxin M1 (AFM1 in raw milk contaminated with known concentration of this toxin. Experiments were carried out at temperature of 4 °C during 35 days. At pH 5.5 Schiff base concentration of 0.1 µmol/L was lessening the concentration of AFM1 after 35 days by 55 %. However, at pH 6.5 the most effective concentration for lessening of AFM1 was 0.5 µmol/L. Schiff base was not effective at pH value of 7 or higher. The ability of Schiff base to act as antimycotoxigenic agent provides new perspective for possibly using this compound to control AFM1 contamination in milk and to extent shelf lives of this food. Detection of toxicity of investigated Schiff base was performed by using the brine shrimp (Artemia salina larvae as an biological indicator to determine their sensitivity to this chemical agent.

  18. Tunable Two-color Luminescence and Host–guest Energy Transfer of Fluorescent Chromophores Encapsulated in Metal-Organic Frameworks

    Science.gov (United States)

    Yan, Dongpeng; Tang, Yanqun; Lin, Heyang; Wang, Dan

    2014-01-01

    Co-assembly of chromophore guests with host matrices can afford materials which have photofunctionalities different from those of individual components. Compared with clay and zeolite materials, the use of metal–organic frameworks (MOFs) as a host structure for fabricating luminescent host–guest materials is still at an early stage. Herein, we report the incorporation of a laser dye, 4-(dicyanomethylene)-2-methyl-6-(4-dimethylaminostyryl)-4H-pyran (DCM), into stilbene-based and naphthalene-based MOF systems. The resulting materials exhibit blue/red two-color emission, and the intensity ratio of blue to red fluorescence varies in different planes within the MOF crystal as detected by 3D confocal fluorescence microscopy. The observed changes in ratiometric fluorescence suggest the occurrence of energy transfer from MOF host to DCM molecules, which can be further confirmed by periodic density functional theoretical (DFT) calculations. Moreover, selective changes in luminescence behavior are observed on treating the guest@MOF samples with volatile organic compounds (methanol, acetone and toluene), indicating that these host–guest systems have potential applications as fluorescence sensors. It can be expected that by rational selection of MOF hosts and guest chromophores with suitable emissive colors and energy levels, a wide variety of multi-color luminescent and energy-transfer systems can readily be prepared in a similar manner. PMID:24614015

  19. Organosulphur compounds in coals as determined by reaction with Raney nickel and microscale pyrolysis techniques. Fifth quarterly report, October 1, 1995--December 31, 1995

    Energy Technology Data Exchange (ETDEWEB)

    Philp, R.P.

    1996-01-31

    This project is designed to study the nature of sulphur-containing organic compounds and their respective linkages in coals and related materials using a variety of microscale pyrolysis techniques combined with gas chromatography--mass spectrometry. The majority of the work will be undertaken using a PYRAN pyrolysis system purchased with funds from the DOE University Instrumentation Program. Since the last report, we have reached the point in the project that we are satisfied with the nickel boride chemical degradation method, and are now working our way through the large amounts of data collected by gas chromatography-mass spectrometry analysis. While we have tentatively identified a variety of compounds produced by the chemical degradation method with spectra from the literature, we have yet to confirm many of these identifications with pure standards or specialized oil samples. As a result we will present in this report chromatograms of one of the coals (Illinois No. 6) and compare the free aliphatic hydrocarbons with those compounds cleaved from the polar extract, asphaltenes and pre-extracted coal matrix.

  20. Comparative metabolism study of β-lapachone in mouse, rat, dog, monkey, and human liver microsomes using liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Lee, Sangkyu; Kim, In Sook; Kwak, Tae Hwan; Yoo, Hye Hyun

    2013-09-01

    β-Lapachone (3,4-dihydro-2,2-dimethyl-2H-naphthol[1,2-b]pyran-5,6-dione) is a natural compound extracted from the bark of the lapacho tree (Tabebuia avellanedae) and is undergoing phase II clinical trials as an antitumor drug candidate. The present study characterized in vitro metabolites of β-lapachone in mouse, rat, dog, monkey and human liver microsomes. β-Lapachone (10 μM) was incubated with mouse, rat, dog, monkey, and human liver microsomes in the presence of NADPH. The reaction mixtures were analyzed by LC/MS and the metabolites were identified based on their elemental composition and product ion spectra. A total of 6 metabolites (M1-M6) were detected in liver microsomes with a slight difference between species. M1 and M6 were identified as a decarbonated metabolite and a carboxylated metabolite, respectively; M2, M3, and M4 were identified as monohydroxylated metabolites; and M5 was identified as an O-methylated metabolite. M5, an O-methylated metabolite was found in rat and human liver microsomes, which is thought to be formed from a catechol intermediate by MB-COMT-mediated methylation and reported here for the first time.

  1. Pyrophen Produced by Endophytic Fungi Aspergillus sp Isolated from Piper crocatum Ruiz and Pav Exhibits Cytotoxic Activity and Induces S Phase Arrest in T47D Breast Cancer Cells.

    Science.gov (United States)

    Astuti, Puji; Erden, Willy; Wahyono; Wahyuono, Subagus; Hertiani, Triana

    2016-01-01

    Ethyl acetate extracts obtained from culture of endophytic fungi Aspergillus sp isolated from Piper crocatum Ruiz and Pav, have been shown to possess cytotoxic activity against T47D breast cancer cells. Investigations were here conducted to determine bioactive compounds responsible for the activity. Bioassay guided fractionation was employed to obtain active compounds. Structure elucidation was performed based on analysis of LC-MS, 1H-NMR, 13C-NMR, COSY, DEPT, HMQC, HMBC data. Cytotoxity assays were conducted in 96 well plates against T47D and Vero cell lines. Bioassay guided isolation and chemical investigation led to the isolation of pyrophen, a 4-methoxy-6-(1'-acetamido-2'-phenylethyl)-2H-pyran-2-one. Further analysis of its activity against T47D and Vero cells showed an ability to inhibit the growth of T47D cells with IC50 values of 9.2 μg/mL but less cytotoxicity to Vero cells with an IC50 of 109 μg/mL. This compound at a concentration of 400 ng/mL induced S-phase arrest in T47D cells.

  2. The Biological Profile of the Less Lipophilic and Synthetically More Accessible Bryostatin 7 Closely Resembles That of Bryostatin 1

    Science.gov (United States)

    Kedei, Noemi; Lewin, Nancy E.; Geczy, Tamas; Selezneva, Julia; Braun, Derek C.; Chen, Jinqiu; Herrmann, Michelle A.; Heldman, Madeleine R.; Lim, Langston; Mannan, Poonam; Garfield, Susan; Poudel, Yam B.; Cummins, Thomas J.; Rudra, Arnab; Blumberg, Peter M.; Keck, Gary E.

    2013-01-01

    The bryostatins are a group of twenty macrolides isolated by Pettit and coworkers from the marine organism Bugula neritina. Bryostatin 1, the flagship member of the family, has been the subject of intense chemical and biological investigations due to its remarkably diverse biological activities, including promising indications as therapy for cancer, Alzheimer’s disease, and HIV. Other bryostatins, however, have attracted far less attention, most probably due to their relatively low natural abundance and associated scarcity of supply. Among all macrolides in this family, bryostatin 7 is biologically the most potent PKC (protein kinase C) ligand (in terms of binding affinity) and also the first bryostatin to be synthesized in the laboratory. Nonetheless, almost no biological studies have been carried out on this agent. We describe herein the total synthesis of bryostatin 7 based on our pyran annulation technology, which allows for the first detailed biological characterizations of bryostatin 7 with side-by-side comparisons to bryostatin 1. The results suggest that the more easily synthesized and less lipophilic bryostatin 7 may be an effective surrogate for bryostatin 1. PMID:23369356

  3. Biological profile of the less lipophilic and synthetically more accessible bryostatin 7 closely resembles that of bryostatin 1.

    Science.gov (United States)

    Kedei, Noemi; Lewin, Nancy E; Géczy, Tamás; Selezneva, Julia; Braun, Derek C; Chen, Jinqiu; Herrmann, Michelle A; Heldman, Madeleine R; Lim, Langston; Mannan, Poonam; Garfield, Susan H; Poudel, Yam B; Cummins, Thomas J; Rudra, Arnab; Blumberg, Peter M; Keck, Gary E

    2013-04-19

    The bryostatins are a group of 20 macrolides isolated by Pettit and co-workers from the marine organism Bugula neritina. Bryostatin 1, the flagship member of the family, has been the subject of intense chemical and biological investigations due to its remarkably diverse biological activities, including promising indications as therapy for cancer, Alzheimer's disease, and HIV. Other bryostatins, however, have attracted far less attention, most probably due to their relatively low natural abundance and associated scarcity of supply. Among all macrolides in this family, bryostatin 7 is biologically the most potent protein kinase C (PKC) ligand (in terms of binding affinity) and also the first bryostatin to be synthesized in the laboratory. Nonetheless, almost no biological studies have been carried out on this agent. We describe herein the total synthesis of bryostatin 7 based on our pyran annulation technology, which allows for the first detailed biological characterizations of bryostatin 7 with side-by-side comparisons to bryostatin 1. The results suggest that the more easily synthesized and less lipophilic bryostatin 7 may be an effective surrogate for bryostatin 1.

  4. Litter Quality of Populus Species as Affected by Free-Air CO2 Enrichment and N-Fertilization

    Directory of Open Access Journals (Sweden)

    Esther Vermue

    2009-01-01

    Full Text Available The effect of elevated CO2 and nitrogen fertilization on the molecular chemistry of litter of three Populus species and associated soil organic matter (SOM was investigated by pyrolysis-gas chromatography/mass spectrometry. The results are based on 147 quantified organic compounds in 24 litter samples. Litter of P. euramerica was clearly different from that of P. nigra and P. alba. The latter two had higher contents of proteins, polysaccharides, and cutin/cutan, while the former had higher contents of phenols and benzofurans/pyrans. The difference between replications was at least as large as the effect of treatments, so that no systematic chemical changes were attributable to CO2 effect or N-fertilization effect. The chemistry of SOM under the various species and treatments did not show significant changes either. The low number of available replicates that is two was clearly insufficient to overcome the effect of spatial variation on litter chemistry and detect small differences in molecular litter chemistry.

  5. Is the hypoglycemic action of vanadium compounds related to the suppression of feeding?

    Science.gov (United States)

    Huang, Meiling; Wu, Yaling; Wang, Na; Wang, Ziwei; Zhao, Pan; Yang, Xiaoda

    2014-03-01

    Vanadium compounds exhibit effective hypoglycemic activity in both type I and type II diabetes mellitus. However, there was one argument that the hypoglycemic action of vanadium compounds could be attributable to the suppression of feeding-one common toxic aspect of vanadium compounds. To clarify this question, we investigated in this work the effect of a vanadyl complex, BSOV (bis((5-hydroxy-4-oxo-4H-pyran-2-yl)methyl-2-hydroxy-benzoatato) oxovanadium (IV)), on diabetic obese (db/db) mice at a low dose (0.05 mmol/kg/day) when BSOV did not inhibit feeding. The experimental results showed that this dose of BSOV effectively normalized the blood glucose level in diabetic mice without affecting the body weight growth. Western blotting assays on the white adipose tissue of db/db mice further indicated that BSOV treatment significantly improved expression of peroxisome proliferator-activated receptor γ (PPARγ) and activated AMP-activated protein kinase (AMPK). In addition, vanadium treatment caused a significant suppression of phosphorylation of c-Jun N-terminal protein kinase (JNK), which plays a key role in insulin-resistance in type II diabetes. This is the first evidence that the mechanism of insulin enhancement action involves interaction of vanadium compounds with JNK. Overall, the present work indicated that vanadium compounds exhibit antidiabetic effects irrelevant to food intake suppression but by modulating the signal transductions of diabetes and other metabolic disorders.

  6. Pharmacological and behavioral characterization of D-473, an orally active triple reuptake inhibitor targeting dopamine, serotonin and norepinephrine transporters.

    Directory of Open Access Journals (Sweden)

    Aloke K Dutta

    Full Text Available Major depressive disorder (MDD is a debilitating disease affecting a wide cross section of people around the world. The current therapy for depression is less than adequate and there is a considerable unmet need for more efficacious treatment. Dopamine has been shown to play a significant role in depression including production of anhedonia which has been one of the untreated symptoms in MDD. It has been hypothesized that drugs acting at all three monoamine transporters including dopamine transporter should provide more efficacious antidepressants activity. This has led to the development of triple reuptake inhibitor D-473 which is a novel pyran based molecule and interacts with all three monoamine transporters. The monoamine uptake inhibition activity in the cloned human transporters expressed in HEK-293 cells (70.4, 9.18 and 39.7 for DAT, SERT and NET, respectively indicates a serotonin preferring triple reuptake inhibition profile for this drug. The drug D-473 exhibited good brain penetration and produced efficacious activity in rat forced swim test under oral administration. The optimal efficacy dose did not produce any locomotor activation. Microdialysis experiment demonstrated that systemic administration of D-473 elevated extracellular level of the three monoamines DA, 5-HT, and NE efficaciously in the dorsal lateral striatum (DLS and the medial prefrontal cortex (mPFC area, indicating in vivo blockade of all three monoamine transporters by D-473. Thus, the current biological data from D-473 indicate potent antidepressant activity of the molecule.

  7. First report about pharmaceutical properties and phytochemicals analysis of Rosa abyssinica R. Br. ex Lindl. (Rosaceae).

    Science.gov (United States)

    Moustafa, Mahmoud Fawzy; Alrumman, Sulaiman Abdullah

    2015-11-01

    In vitro antimicrobial efficacy of seven solvent extracts from leaves and hips of Saudi Arabian weed Rosa abyssinica against a variety of human pathogenic bacteria and Candida species have been evaluated using well diffusion methods. Phytochemicals present in the leaves and hips of Rosa abyssinica has been characterized using Gas Chromatogram Mass spectrometry analysis. The extracts comparative efficacy against tested microbes gained from the fresh and dry leaves exhibited more prominent activity than fresh and dry hips. The methanol, chloroform, petroleum ether, acetone and diethyl ether extracts have a greater lethal effect on pathogenic microbes than hot water extracts, while cold-water extracts showed no activity. Twenty-four phytochemicals have been characterized from ethanol extract of the leaves of Rosa abyssinica and fifteen from hips by GC-MS. The major compounds detected in the leaves were squalene (38.21%), ethane, 1,1-diethoxy- (9.65%), β-D-glucopyranose, 1,6-anhydro- (8.55%), furfural (5.50%) and 2-furancarboxaldehyde 5-(hydroxymethyl)- (5.19%). The major compounds in the hips were 2-furancarboxaldehyde 5-(hydroxymethyl)- (51.27%), β-D-glucopyranose, 1,6-anhydro- (8.18%), 4H-pyran-4-one, 2,3-dihydro-3,5-dihydroxy-6-methyl- (7.42%), 2,5-furandione, dihydro-3-methylene- (6.79%) and furfural (5.99%). Current findings indicate that extract from leaves and hips of Rosa abyssinica and the bioactive components present could be used as pharmaceutical agents.

  8. Molecular imprinted polymer-coated optical fiber sensor for the identification of low molecular weight molecules.

    Science.gov (United States)

    Lépinay, Sandrine; Ianoul, Anatoli; Albert, Jacques

    2014-10-01

    A biomimetic optical probe for detecting low molecular weight molecules (maltol, 3-hydroxy-2-methyl-4H-pyran-4-one, molecular weight of 126.11 g/mol), was designed, fabricated, and characterized. The sensor couples a molecular imprinted polymer (MIP) and the Bragg grating refractometry technology into an optical fiber. The probe is fabricated first by inscribing tilted grating planes in the core of the fiber, and then by photopolymerization to immobilize a maltol imprinted MIP on the fiber cladding surface over the Bragg grating. The sensor response to the presence of maltol in different media is obtained by spectral interrogation of the fiber transmission signal. The results showed that the limit of detection of the sensor reached 1 ng/mL in pure water with a sensitivity of 6.3 × 10(8)pm/M. The selectivity of the sensor against other compounds and its reusability were also studied experimentally. Finally, the unambiguous detection of concentrations as little as 10nM of maltol in complex media (real food samples) by the MIP-coated tilted fiber Bragg grating sensor was demonstrated.

  9. A variety of volatile compounds as markers in unifloral honey from dalmatian sage (Salvia officinalis L.).

    Science.gov (United States)

    Jerković, Igor; Mastelić, Josip; Marijanović, Zvonimir

    2006-12-01

    Volatile compounds of unifloral Salvia officinalis L. honey has been investigated for the first time. The botanical origin of ten unifloral Salvia honey samples has been ascertained by pollen analysis (the honey samples displayed 23-60% of Salvia pollen). Fifty-four volatile compounds were identified by GC and GC/MS in ten Salvia honey extracts obtained by ultrasound-assisted extraction (USE) with pentane/Et(2)O 1 : 2. The yield of isolated volatiles varied from 25.7 to 30.5 mg kg(-1). Salvia honey could be distinguished on the basis of the high percentage of benzoic acid (6.4-14.8%), and especially phenylacetic acid (5.7-18.4%). Minor, but floral-origin important volatiles were identified such as shikimate pathway derivatives, 'degraded-carotenoid-like' structures (3,5,5-trimethylcyclohex-2-ene derivatives) and 2,6,6-trimethylcyclohex-2-ene derivatives. Compounds from other metabolic pathways such as aliphatic acids and higher linear hydrocarbons, as well as heterocycles (pyrans, furans, and pyrroles), were also present. Most of the identified compounds do not constitute specific Salvia honey markers, due to their presence in honeys of other botanical origins; however, their ratio in different honeys could be useful to distinguish floral origin. Salvia-honey volatile markers were: benzoic acid, phenylacetic acid, p-anisaldehyde, alpha-isophorone, 4-ketoisophorone, dehydrovomifoliol, 2,6,6-trimethyl-4-oxocyclohex-2-ene-1-carbaldehyde, 2,2,6-trimethylcyclohexane-1,4-dione, and coumaran.

  10. GSH-Activated NIR Fluorescent Prodrug for Podophyllotoxin Delivery.

    Science.gov (United States)

    Liu, Yajing; Zhu, Shaojia; Gu, Kaizhi; Guo, Zhiqian; Huang, Xiaoyu; Wang, Mingwei; Amin, Hesham M; Zhu, Weihong; Shi, Ping

    2017-09-06

    Theranostic prodrug therapy enables the targeted delivery of anticancer drugs with minimized adverse effects and real-time in situ monitoring of activation of the prodrugs. In this work, we report the synthesis and biological assessment of the near-infrared (NIR) prodrug DCM-S-PPT and its amphiphilic copolymer (mPEG-DSPE)-encapsulated nanoparticles. DCM-S-PPT is composed of podophyllotoxin (PPT) as the anticancer moiety and a dicyanomethylene-4H-pyran (DCM) derivative as the NIR fluorescent reporter, which are linked by a thiol-specific cleavable disulfide bond. In vitro experiments indicated that DCM-S-PPT has low cytotoxicity and that glutathione (GSH) can activate DCM-S-PPT resulting in PPT release and a concomitant significant enhancement in NIR fluorescence at 665 nm. After being intravenously injected into tumor-bearing nude mice, DCM-S-PPT exhibited excellent tumor-activated performance. Furthermore, we have demonstrated that mPEG-DSPE as a nanocarrier loaded with DCM-S-PPT (mPEG-DSPE/DCM-S-PPT) showed even greater tumor-targeting performance than DCM-S-PPT on account of the enhanced permeability and retention effect. Its tumor-targeting ability and specific drug release in tumors make DCM-S-PPT a promising prodrug that could provide a significant strategy for theranostic drug delivery systems.

  11. NATURAL POLYACETYLENE COMPOUNDS

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    D. A. Konovalov

    2014-01-01

    Full Text Available Polyacetylenes (polyynes are compounds which contain two or more triple bonds in its structure. About 2 000 different polyacetylenes and biogenetically related substances were identified in 24 families of higher plants. However, most of these compounds were found in seven families of flowering plants: Apiaceae (Umbelliferae, Araliaceae, Asteraceae (Compositae, Campanulaceae, Olacaceae, Pittosporaceae and Santalaceae. Polyacetylenes are relatively unstable, chemically and biologically active compounds, and present in fungi, microorganisms, marine invertebrates and other organisms except for plants. Acetylenes form distinct specialized group of chemically active natural compounds, which are biosynthesized in plants of unsaturated fatty acids. In addition to widespread aliphatic polyacetylenes thiophenes dithiacyclohexadienes (thiarubrines, thioethers, sulphoxides, sulphones, alkamides, chlorohydrins, lactones, spiroacetal enol ethers, furans, pyrans, tetrahydropyrans, isocoumarins, aromatic acetylenes were also found in plant species. Polyacetylenes are localized in different plant organs, and can be found both individually and as a compound with carbohydrates, terpene, phenolic and other compounds. Many polyacetylenes are found in the composition of the essential oils of plants and it confirms their strongly marked ecological functions. From biological point of view these compounds are often synthesized by plants as toxic or bitter antifeedants, allelopathic compounds, phytoalexins or broadly antibiotic components. Polyynes are strong photosensitizers. They exhibit anti-inflammatory, anti-coagulant, anti-bacterial, antituberculosis, anti-fungal, anti-viral, neuroprotective and neurotoxic activity. Immunostimulatory influence associated with certain allergenicity of some of these substances was established. Therefore, without a doubt polyacetylenes are of interest for the modern pharmacy and medicine.

  12. Enhancement of the Color Rendering Index of White Organic Light-Emitting Devices Based on a Blue and Red Emitting Layer with a Y3Al5O12:Ce3+ Green Phosphor Color-Conversion Layer.

    Science.gov (United States)

    Jang, J S; Lee, K S; Lee, E J; Kwon, M S; Kim, T W

    2015-01-01

    White organic light-emitting devices (WOLEDs) were fabricated utilizing blue and red emitting organic light-emitting devices and a color conversion layer (CCL) made of yttrium aluminum garnet (YAG:Ce3+) phosphors embedded into polymethylmethacrylate. The good color balance for the color conversion of the WOLEDs was achieved utilizing 20-nm blue and 10-nm red OLEDs. The electroluminescence spectrum for the fabricated device showed a white color consisting of the blue color from the 4,4-bis(2,2-diphenylethen-1-yl)bipheny layer, the red color from the tris-(8-hydroxyquinolinato) aluminum: 4-(dicyanomethylene)-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran layer, and the green color from the YAG:Ce3+ phosphor. The Commission Internationale de l'Eclairage coordinates of the WOLEDs slightly shifted from (0.25, 0.23) of the blue and red emission OLEDs without phosphors to (0.34, 0.35) of the OLEDs with green phosphors, indicative of the pure white color. WOLEDs with a CCL exhibited three wavelength white emissions with a color rendering index of 86.

  13. GC-MS analysis of bioactive compounds in the methanol extract of Clerodendrum viscosum leaves

    Directory of Open Access Journals (Sweden)

    Pritipadma Panda

    2015-01-01

    Full Text Available Background: Clerodendrum viscosum is commonly found in India and Bangladesh. Previously, various parts of this plant were reported for treatment of different types of diseases and there was no report on GC-Ms analysis. Objective: To analyze and characterize the phytochemical compounds of methanol extract of Clerodendrum viscosum using GC-MS. Materials and Methods: The preliminary phytochemical screening of methanol extract was carried out according to standard procedures described in WHO guidelines. Various bioactive compounds of the extract were determined by GC-MS technique. Results: The presence of steroids, triterpenoids, alkaloids, saponins, flavonoids, tannins and carbohydrate was found on phytochemical screening of methanol extract of the leaves. The GC-MS analysis showed 16 peaks of different phytoconstituents namely acetamide,N,N-carbonylbis-, 4-Pyranone,2,3-dihydro-, alpha-D-Galactofuranoside, methyl 2,3,5,6-tetra-O-methyl-, Glycerin, Xylitol, N,N-Dimethylglycine, 4H-Pyran-4-one,2,3-dihydro-3, 5-dihydroxy-6-methyl-, Benzofuran,2,3-dihydro-, 5-Hydroxymethylfurfural, 2(1HPyrimidinone,1-methyl-, 2,4-Dihydroxy-5,6-dimethylpyrimidine, 3-Deoxy-d-mannoic lactone, 1,3-Methylene-d-arabitol, Orcinol, n-Hexadecanoic acid and Phenol,4,4′-(1-methyl ethylidene bis etc. Conclusion: The bioactive compounds present in the methanol extract of Clerodendrum viscosum suggest the application of this extract for the treatment of various diseases by the aborigine tribes.

  14. 4-Cyano-N-ethylspiro[chromene-2,4′-piperidine]-1′-carboxamide

    Directory of Open Access Journals (Sweden)

    P. Rajalakshmi

    2013-01-01

    Full Text Available The title compound, C17H19N3O2, crystallizes with two independent molecules (A and B in the asymmetric unit. In both molecules, the pyran ring has a twisted conformation (5S4, with Q = 0.301 (3 Å, θ = 116.7 (6 and ϕ= 213.6 (7° for molecule A, and Q = 0.364 (2 Å, θ = 113.7 (3 and ϕ = 213.0 (4° for molecule B. In molecule B, the terminal ethyl group is disordered over two orientations with an occupancy ratio of 0.55 (1:0.45 (1. In the crystal, molecules A and B form very similar but separate R12(7 motifs through N—H...O and C—H...O hydrogen bonds. The resulting chains along [001] are interlinked by weaker C—H...O and C—H...π interactions, forming layers parallel to the bc plane.

  15. 6-Chloro-7-fluoro-4-oxo-4H-chromene-3-carbaldehyde

    Directory of Open Access Journals (Sweden)

    Yoshinobu Ishikawa

    2014-07-01

    Full Text Available In the title compound, C10H4ClFO3, a chlorinated and fluorinated 3-formylchromone derivative, all atoms are essentially coplanar (r.m.s. = 0.0336 Å for the non-H atoms, with the largest deviation from the least-squares plane [0.062 (2 Å] being for a benzene-ring C atom. In the crystal, molecules are linked through stacking interactions [centroid–centroid distance between the benzene and pyran rings = 3.958 (3 Å and interplanar distance = 3.259 (3 Å], C—H...O hydrogen bonds, and short C...O contacts [2.879 (3 Å]. Unsymmetrical halogen–halogen interactions between the Cl and F atoms [Cl...F = 3.049 (3 Å, C—Cl...F = 148.10 (9° and C—F...Cl = 162.06 (13°] are also formed, giving a meandering two-dimensional network along the a axis.

  16. (6′R*,7′R*-7′-(1,3,-Diphenyl-1H-pyrazol-4-yl-1,2,5′,6′,7′,7a',3′′,4′′-octahydro-1′H,2′′H-dispiro[acenaphthylene-1,5′-pyrrolo[1,2-c][1,3]thiazole-6′,3′′-[1]benzopyran]-2,4′′-dione

    Directory of Open Access Journals (Sweden)

    J. Murugan

    2013-04-01

    Full Text Available In the title compound, C40H29N3O3S, the pyran ring adopts a sofa conformation, the thiazolidine ring adopts a twisted conformation and the pyrrolidine ring adopts an envelope conformation with the N atom as the flap. The pyrazole ring is essentially planar [maximum deviation = 0.002 (2 Å] and forms dihedral angles of 4.8 (1 and 39.0 (1°, respectively, with the benzene rings attached to the N and C atoms. The acenapthylene ring system is approximately planar [maximum deviation = 0.058 (2 Å] and forms dihedral angles of 85.9 (1 and 48.5 (1°, respectively, with the pyrollothiazole and chromene ring systems. The molecular conformation is stabilized by three weak intramolecular C—H...O hydrogen bonds, which generate one S(8 and two S(6 ring motifs. In the crystal, pairs of C—H...O hydrogen bonds link centrosymmetrically related molecules into dimers, generating R22(14 ring motifs. The crystal packing also features pairs of C—H...π interactions, which link the dimers into a supramolecular chain along the b axis.

  17. Detailed analysis of ultrathin fluorescent red dye interlayer for organic photovoltaic cells

    Institute of Scientific and Technical Information of China (English)

    Zang Yue; Yu Jun-Sheng; Wang Na-Na; Jiang Ya-Dong

    2011-01-01

    The influence of an ultrathin 4-(dicyanomethylene)-2-t-butyl-6-(1,1,7,7-tetramethyljulolidyl-9-enyl)-4H-pyran (DCJTB) fluorescent dye layer at donor/acceptor heterojunction on the performance of small-molecule organic photovoltaic (OPV) cell is studied. The structure of OPV cell is of indium-tin oxide (ITO)/copper phthalocyanine (CuPc)/DCJTB/fullerene (C60)/bathophenanthroline (Bphen)/Ag. The results show that open circuit voltage (Voc)increases to 0.57 V as the fihn thicknees of DCJTB layer increases from 0.2 to 2.0 nm. By using an equivalent circuit model, the enhancement of Voc is found to be attributed to the reduced reverse saturation current density (Js) which is due to the lower highest occupied molecular orbital (HOMO) level in DCJTB than that in CuPc. Also, the short circuit current density (Jsc) is affected when the DCJTB layer becomes thicker, resulting from the high series resistance RsA due to the low charge carrier mobility of fluorescent red dye.

  18. Metabolomics by Proton High-Resolution Magic-Angle-Spinning Nuclear Magnetic Resonance of Tomato Plants Treated with Two Secondary Metabolites Isolated from Trichoderma.

    Science.gov (United States)

    Mazzei, Pierluigi; Vinale, Francesco; Woo, Sheridan Lois; Pascale, Alberto; Lorito, Matteo; Piccolo, Alessandro

    2016-05-11

    Trichoderma fungi release 6-pentyl-2H-pyran-2-one (1) and harzianic acid (2) secondary metabolites to improve plant growth and health protection. We isolated metabolites 1 and 2 from Trichoderma strains, whose different concentrations were used to treat seeds of Solanum lycopersicum. The metabolic profile in the resulting 15 day old tomato leaves was studied by high-resolution magic-angle-spinning nuclear magnetic resonance (HRMAS NMR) spectroscopy directly on the whole samples without any preliminary extraction. Principal component analysis (PCA) of HRMAS NMR showed significantly enhanced acetylcholine and γ-aminobutyric acid (GABA) content accompanied by variable amount of amino acids in samples treated with both Trichoderma secondary metabolites. Seed germination rates, seedling fresh weight, and the metabolome of tomato leaves were also dependent upon doses of metabolites 1 and 2 treatments. HRMAS NMR spectroscopy was proven to represent a rapid and reliable technique for evaluating specific changes in the metabolome of plant leaves and calibrating the best concentration of bioactive compounds required to stimulate plant growth.

  19. 2-Amino-4-(4-bromophenyl-6-methoxy-4H-benzo[h]chromene-3-carbonitrile

    Directory of Open Access Journals (Sweden)

    Al-anood M. Al-dies

    2013-04-01

    Full Text Available In the title compound, C21H15BrN2O2, the 14 non-H atoms of the 4H-benzo[h]chromene fused-ring system are approximately coplanar (r.m.s. deviation = 0.129 Å. Within this system, the 4H-pyran ring adopts a flattened half-chair conformation with the methine C atom lying 0.281 (4 Å above the plane of the remaining atoms (r.m.s. deviation = 0.0446 Å. The bromobenzene ring is almost perpendicular to the fused-ring system [dihedral angle = 85.34 (13°]. In the crystal, supramolecular layers parallel to (101 are sustained by amine–cyano N—H...N and amine–methoxy N—H...O hydrogen bonds. The layers stack with interactions of the type (bromobenzeneC—H...π(outer-C6 ring of the fused-ring system connecting them.

  20. Ethyl 2-amino-4-(4-bromophenyl-6-methoxy-4H-benzo[h]chromene-3-carboxylate

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    Seik Weng Ng

    2013-03-01

    Full Text Available In the title compound, C23H20BrNO4, the pyran ring has a flattened boat conformation with the O and methine C atoms lying to one side of the plane [0.160 (5 and 0.256 (6 Å, respectively] defined by the remaining atoms. Nevertheless, the 4H-benzo[h]chromene ring system approximates a plane (r.m.s. deviation = 0.116 Å with the bromobenzene ring almost perpendicular [dihedral angle = 83.27 (16°] and the ester group coplanar [C—C—C—O = 3.4 (5°]; the methoxy substituent is also coplanar [C—O—C—C = 174.5 (3°]. In addition to an intramolecular N—H...O(ester carbonyl hydrogen bond, the ester carbonyl O atom also forms an intermolecular N—H...O hydrogen bond with the second amine H atom, generating a zigzag supramolecular chain along the c axis in the crystal packing. The chains are linked into layers in the bc plane by N—H...Br hydrogen bonds, and these layers are consolidated into a three-dimensional architecture by C—H...π interactions.

  1. A novel strategy for the development of selective active-site inhibitors of the protein tyrosine phosphatase-like proteins islet-cell antigen 512 (IA-2) and phogrin (IA-2 beta)

    DEFF Research Database (Denmark)

    Drake, P.G.; Peters, Günther H.j.; Andersen, H.S.

    2003-01-01

    ] pyran-3-carboxylic acid ('Compound 6' shown in the main paper), which inhibited IA-2beta((S762Y/Y898P/D933A)) (IA-2beta in which Ser(762) has been mutated to tyrosine, Tyr(898) to proline, and Asp(933) to alanine) with a K-i value of approximate to 8 muM, appeared ideal for future lead optimization...... into highly selective and potent inhibitors of PTP1B. However. since wild-type IA-2 and IA-2beta lack conventional PTP activity, a novel strategy was designed whereby catalytically active species were generated by 'back-mutating key non-consensus catalytic region residues to those of PTP1B. These mutants were...... then used as tools with which to test the potency and selectivity of OBA and a variety of its derivatives. Catalytically competent IA-2 and IA-2beta species were generated by 'back-mutation' of only three key residues (equivalent to Tyr(46). Asp(181) and Ala(217) using the human PTP1B numbering) to those...

  2. Oxovitisins: a new class of neutral pyranone-anthocyanin derivatives in red wines.

    Science.gov (United States)

    He, Jingren; Oliveira, Joana; Silva, Artur M S; Mateus, Nuno; De Freitas, Victor

    2010-08-11

    A new class of stable yellowish pigments with similar unique spectral features, displaying only a pronounced broad band around 370 nm in the UV-vis spectrum, was detected in an aged Port wine fraction obtained by a combination of chromatography on TSK Toyopearl HW-40(s) and Polyamide resins. These compounds were identified by liquid chromatography-diode array detector/electrospray ionization mass spectrometry (LC-DAD/ESI/MS) and shown to be direct oxidative derivatives of carboxy-pyranoanthocyanins (vitisins A) by synthesis experiments performed in a wine model solution. Their structures were fully characterized by MS and NMR spectroscopy ((1)H, gCOSY, gHSQC, and gHMBC) and found to correspond to alpha-pyranone-anthocyanins (lactone or pyran-2-one-anthocyanins). Their formation involves first the nucleophilic attack of water into the positively charged C-10 position of vitisins, followed by decarboxylation, oxidation, and dehydration steps, yielding a new and neutral pyranone structure. The occurrence of these novel pigments in aged wines points to a new pathway involving anthocyanin secondary products (vitisins A) as precursors of new pigments in subsequent stages of wine aging that may contribute to its color evolution.

  3. White organic light emitting diodes based on DCM dye sandwiched in 2-methyl-8-hydroxyquinolinolatolithium

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Amit [Center for Organic Electronics, Polymeric and Soft Materials Section, National Physical Laboratory (Council of Scientific and Industrial Research), Dr. K.S. Krishnan Road, New Delhi 110012 (India); Department of Chemistry, M.D. University, Rohtak, Haryana 124001 (India); Srivastava, Ritu, E-mail: ritu@mail.nplindia.ernet.i [Center for Organic Electronics, Polymeric and Soft Materials Section, National Physical Laboratory (Council of Scientific and Industrial Research), Dr. K.S. Krishnan Road, New Delhi 110012 (India); Bawa, Sukhwant S. [Center for Organic Electronics, Polymeric and Soft Materials Section, National Physical Laboratory (Council of Scientific and Industrial Research), Dr. K.S. Krishnan Road, New Delhi 110012 (India); Singh, Devender; Singh, Kapoor [Department of Chemistry, M.D. University, Rohtak, Haryana 124001 (India); Chauhan, Gayatri [Center for Organic Electronics, Polymeric and Soft Materials Section, National Physical Laboratory (Council of Scientific and Industrial Research), Dr. K.S. Krishnan Road, New Delhi 110012 (India); Singh, Ishwar [Department of Chemistry, M.D. University, Rohtak, Haryana 124001 (India); Kamalasanan, Modeeparampil N. [Center for Organic Electronics, Polymeric and Soft Materials Section, National Physical Laboratory (Council of Scientific and Industrial Research), Dr. K.S. Krishnan Road, New Delhi 110012 (India)

    2010-08-15

    Stable white electroluminescence (EL) has been achieved from organic LED, in which an ultrathin 4-(dicyanomethylene)-2-methyl-6-(p-dimethyl-aminostyryl)-4H-pyran (DCM) dye layer has been inserted in between two 2-methyl-8-hydroxyquinolinolatolithium [LiMeq] emitter layer and by optimizing the position of the DCM dye layer from the {alpha}-NPD/LiMeq interface. Electroluminescence spectra, current-voltage-luminescence (I-V-L) characteristics of the devices have been studied by changing the position of the dye layer. As the distance of DCM layer from {alpha}-NPD/LiMeq interface is increased, the intensity of host emission enhances rapidly. Introduction of thin layer of DCM in emissive layer increases the turn on voltage. The best Commission International de L' Eclairage (CIE) coordinates i.e. (0.32, 0.33) were obtained with device structure ITO/{alpha}-NPD(30 nm) /LiMeq(10 nm)/DCM(1 nm)/LiMeq(25 nm)/BCP(6 nm)/Alq{sub 3}(28 nm)/LiF(1 nm)/Al(100 nm). The EL spectrum covers the whole visible spectra range 400-700 nm. The color rendering index (CRI) for our best white light (Device 4) is 47.4. The device shows very good color stability in terms of CIE coordinates with voltages. The maximum luminescence 1240 cd/m{sup -2} has been achieved at 19 V.

  4. Sex pheromone of browntail moth, Euproctis chrysorrhea (L.): synthesis and field deployment.

    Science.gov (United States)

    Khrimian, Ashot; Lance, David R; Schwarz, Meier; Leonhardt, Barbara A; Mastro, Victor C

    2008-04-09

    The browntail moth, Euproctis chrysorrhea (L.), is native to Eurasia, where periodic outbreaks result in defoliation of forest, shade, and ornamental trees. In addition to the damage caused by defoliation, human contact with larval urticating hairs often results in severe dermatitis. Hence, tools for monitoring and controlling the moth populations are desirable. The female-produced sex pheromone of the browntail moth was identified previously, but the synthesis had not been published. This paper reports the synthesis of the pheromone of the browntail moth, (7Z,13Z,16Z,19Z)-docosatetraenyl isobutyrate, using in a key step a Wittig olefination of (6Z)-13-(tetrahydo-2H-pyran-2-yloxy)tridecenal. Field trapping studies were conducted with rubber septa and string formulations of the pheromone and included dose-response, pheromone purity, and dispenser-aging trials. It was found that traps baited with 250 microg of pheromone of 91-94% isomeric purity (main impurity presumably being the 13E isomer) on rubber septa are suitable for monitoring moth populations during the entire flight season.

  5. Visual detection and sequential injection determination of aluminium using a cinnamoyl derivative.

    Science.gov (United States)

    Elečková, Lenka; Alexovič, Michal; Kuchár, Juraj; Balogh, Ioseph S; Andruch, Vasil

    2015-02-01

    A cinnamoyl derivative, 3-[4-(dimethylamino)cinnamoyl]-4-hydroxy-6-methyl-3,4-2H-pyran-2-one, was used as a ligand for the determination of aluminium. Upon the addition of an acetonitrile solution of the ligand to an aqueous solution containing Al(III) and a buffer solution at pH 8, a marked change in colour from yellow to orange is observed. The colour intensity is proportional to the concentration of Al(III); thus, the 'naked-eye' detection of aluminium is possible. The reaction is also applied for sequential injection determination of aluminium. Beer׳s law is obeyed in the range from 0.055 to 0.66 mg L(-1) of Al(III). The limit of detection, calculated as three times the standard deviation of the blank test (n=10), was found to be 4 μg L(-1) for Al(III). The method was applied for the determination of aluminium in spiked water samples and pharmaceutical preparations. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Geranyl flavonoids from the leaves of Artocarpus altilis.

    Science.gov (United States)

    Wang, Yu; Xu, Kedi; Lin, Lin; Pan, Yuanjiang; Zheng, Xiaoxiang

    2007-05-01

    Five geranyl dihydrochalcones, 1-(2,4-dihydroxyphenyl)-3-{4-hydroxy-6,6,9-trimethyl-6a,7,8,10a-tetrahydro-6H-dibenzo[b,d]pyran-5-yl}-1-propanone (2), 1-(2,4-dihydroxyphenyl)-3-[3,4-dihydro-3,8-dihydroxy-2-methyl-2-(4-methyl-3-pentenyl)-2H-1-benzopyran-5-yl]-1-propanone (4), 1-(2,4-dihydroxyphenyl)-3-[8-hydroxy-2-methyl-2-(3,4-epoxy-4-methyl-1-pentenyl)-2H-1-benzopyran-5-yl]-1-propanone (5), 1-(2,4-dihydroxyphenyl)-3-[8-hydroxy-2-methyl-2-(4-hydroxy-4-methyl-2-pentenyl)-2H-1-benzopyran-5-yl]-1-propanone (8), and 2-[6-hydroxy-3,7-dimethylocta-2(E),7-dienyl]-2',3,4,4'-tetrahydroxydihydrochalcone (9), along with four known geranyl flavonoids (1, 3, 6, 7), were isolated from the leaves of Artocarpus altilis. Their structures were established by spectroscopic means and by comparison with the literature values. Compounds 2, 4, and 9 exhibited moderate cytotoxicity against SPC-A-1, SW-480, and SMMC-7721 human cancer cells.

  7. Characterization of the Key Aroma Compounds in Heat-Processed Licorice (Succus Liquiritiae) by Means of Molecular Sensory Science.

    Science.gov (United States)

    Wagner, Juliane; Schieberle, Peter; Granvogl, Michael

    2017-01-11

    Application of the sensomics concept elucidated the key odorants of heat-processed licorice (Succus Liquiritiae). Forty-nine aroma-active compounds with flavor dilution (FD) factors between 16 and 2048 were detected; 47 thereof were identified, 23 for the first time in heated licorice. 4-Hydroxy-2,5-dimethylfuran-3(2H)-one revealed the highest FD factor of 2048, followed by 3-hydroxy-4,5-dimethylfuran-2(5H)-one, 4-hydroxy-3-methoxybenzaldehyde, 3-hydroxy-2-methyl-4H-pyran-4-one, and 2-methoxyphenol (all 1024). Forty-two substances were quantitated by stable isotope dilution assays (SIDAs), and odor activity values (OAVs; ratio of concentration to the respective odor threshold) were calculated revealing OAVs ≥ 1 for 29 compounds. Thereby, 3-hydroxy-4,5-dimethylfuran-2(5H)-one, 2,3-butanedione, 2-methoxyphenol, and 1,8-cineole showed the highest OAVs in Succus Liquiritiae. To validate the obtained data, a reconstitution model based on an aqueous sucrose solution (50%) was prepared, containing all 29 odorants with an OAV ≥ 1 in their naturally occurring concentrations. The recombinate elicited an aroma profile matching very well with the profile of the original heat-processed licorice, proving the correct identification and quantitation of all key aroma compounds of Succus Liquiritiae.

  8. Analysis of the volatiles emitted by whole flowers and isolated flower organs of the carob tree using HS-SPME-GC/MS.

    Science.gov (United States)

    Custódio, Luísa; Serra, Hugo; Nogueira, José Manuel F; Gonçalves, Sandra; Romano, Anabela

    2006-05-01

    The volatiles emitted by fresh whole flowers and isolated flower organs of male, female, and hermaphrodite carob trees (Ceratonia siliqua L.; Leguminosae) were analyzed by headspace solid-phase microextraction followed by capillary gas chromatography and mass spectrometry. The headspace of carob flowers is mainly constituted of high amounts of monoterpenes and sesquiterpenes, and more than 25 compounds were identified. The gender and cultivar affected both the qualitative profile and the relative abundances of the volatiles of whole flowers and isolated floral organs. Linalool and its derivatives (cis-linalool furan oxide, 2,2,6-trimethyl-3-keto-6-vinyltetrahydropyran, cis-linalool pyran oxide, and trans-linalool furan oxide), alpha-pinene, and alpha-farnesene were the dominant volatiles. Female flowers had a higher diversity of volatile compounds than males and hermaphrodites, but a lower abundance of the major ones. Similarly, the floral scent of female flowers of cv. Mulata had a higher content of volatiles but a lower abundance of the major ones, when compared to cv. Galhosa. In each of the three gender types of flowers, the nectary disks seemed to be the major source of volatiles.

  9. Sac-0601 prevents retinal vascular leakage in a mouse model of diabetic retinopathy.

    Science.gov (United States)

    Maharjan, Sony; Lee, Sujin; Agrawal, Vijayendra; Choi, Hyun-Jung; Maeng, Yong-Sun; Kim, Kyeojin; Kim, Nam-Jung; Suh, Young-Ger; Kwon, Young-Guen

    2011-04-25

    Endothelium integrity is important for the normal functioning of vessels, the disruption of which can lead to disease. The blood-retinal barrier required for normal retinal function is compromised in diabetic retinopathy, causing retinal vascular leakage. Previously, we demonstrated the ability of Sac-0601[((2R,3S)-3-acetoxy-6-((3S,10R,13R,17R)-10,13-dimethyl-17-((R)-6-methylheptan-2-yl)-2,3,4,7,8,9,10,11,12,13,14,15,16,17-tetradecahydro-1H-cyclopenta[a]phenanthren-3-yloxy)-3,6-dihydro-2H-pyran-2-yl)methyl acetate], a pseudo-sugar derivative of cholesterol, to increase survival of retinal endothelial cells. In the present study, we evaluated the ability of Sac-0601 to prevent retinal vascular leakages in vitro and in vivo. Sac-0601 treatment blocked VEGF-induced formation of actin stress fibers and stabilized the cortical actin ring in retinal endothelial cells. It also inhibited degradation of occludin, an important tight junction protein, and blocked VEGF-induced disruption of its linear pattern at the cell border. The [(14)C] sucrose permeability assay demonstrated that Sac-0601 was able to prevent VEGF-induced retinal endothelial permeability. The compound inhibited the vascular leakage in retina of mice intravitreally injected with VEGF. And it also significantly reduced the leakage in retina of diabetic retinopathy mice model. Taken together, our findings suggest the potential therapeutic usefulness of Sac-0601 for retinal vascular permeability diseases.

  10. Physical and optical properties of DCJTB dye for OLED display applications: Experimental and theoretical investigation

    Science.gov (United States)

    Kurban, Mustafa; Gündüz, Bayram

    2017-06-01

    In this study, 4-(dicyanomethylene)-2-tert-butyl-6-(1,1,7,7-tetramethyljulolidin-4-yl-vinyl)-4H-pyran (DCJTB) was achieved using the experimental and theoretical studies. The electronic, optical and spectroscopic properties of DCJTB molecule were first investigated by performing experimental both solution and thin film techniques and then theoretical calculations. Theoretical results showed that one intense electronic transition is 505.26 nm a quite reasonable and agreement with the measured experimental data 505.00 and 503 nm with solution technique and film technique, respectively. Experimental and simple models were also taken into consideration to calculate the optical refractive index (n) of DCJTB molecule. The structural and electronic properties were next calculated using density functional theory (DFT) with B3LYP/6-311G (d, p) basis set. UV, FT-IR spectra characteristics and the electronic properties, such as frontier orbitals, and band gap energy (Eg) of DCJTB were also recorded time-dependent (TD) DFT approach. The theoretical Eg value were found to be 2.269 eV which is consistent with experimental results obtained from solution technique for THF solvent (2.155 eV) and literature (2.16 eV). The results herein obtained reveal that solution is simple, cost-efficient and safe for optoelectronic applications when compared with film technique.

  11. Exploration of flexible phenylpropylurea scaffold as novel cardiac myosin activators for the treatment of systolic heart failure.

    Science.gov (United States)

    Manickam, Manoj; Jalani, Hitesh B; Pillaiyar, Thanigaimalai; Sharma, Niti; Boggu, Pulla Reddy; Venkateswararao, Eeda; Lee, You-Jung; Jeon, Eun-Seok; Jung, Sang-Hun

    2017-07-07

    A series of flexible urea derivatives have been synthesized and demonstrated as selective cardiac myosin ATPase activator. Among them 1-phenethyl-3-(3-phenylpropyl)urea (1, cardiac myosin ATPase activation at 10 μM = 51.1%; FS = 18.90; EF = 12.15) and 1-benzyl-3-(3-phenylpropyl)urea (9, cardiac myosin ATPase activation = 53.3%; FS = 30.04; EF = 18.27) showed significant activity in vitro and in vivo. The change of phenyl ring with tetrahydropyran-4-yl moiety viz., 1-(3-phenylpropyl)-3-((tetrahydro-2H-pyran-4-yl)methyl)urea (14, cardiac myosin ATPase activation = 81.4%; FS = 20.50; EF = 13.10), and morpholine moiety viz., 1-(2-morpholinoethyl)-3-(3-phenylpropyl)urea (21, cardiac myosin ATPase activation = 44.0%; FS = 24.79; EF = 15.65), proved to be efficient to activate the cardiac myosin. The potent compounds 1, 9, 14 and 21 were found to be selective for cardiac myosin over skeletal and smooth myosins. Thus, these urea derivatives are potent scaffold to develop as a newer cardiac myosin activator for the treatment of systolic heart failure. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  12. Spectroscopic and biological activities studies of bivalent transition metal complexes of Schiff bases derived from condensation of 1,4-phenylenediamine and benzopyrone derivatives.

    Science.gov (United States)

    Sherif, Omaima E; Abdel-Kader, Nora S

    2014-01-03

    Many tools of analysis such as elemental analyses, infrared, ultraviolet-visible, electron spin resonance (ESR) and thermal analysis, as well as conductivity and magnetic susceptibility measurements were used to elucidate the structures of the newly prepared Co(II), Ni(II) and Cu(II) complexes with Schiff bases derived from the condensation of 1,4-phenylenediamine with 6-formyl-7-hydroxy-5-methoxy-2-methylbenzo-pyran-4-one (H2L) or 5,7-dihydroxy-6-formyl-2-methylbenzopyran-4-one (H4L). The data showed that all formed complexes are 1:1 or 2:2 (M:L) and non-electrolyte chelates. The Co(II) and Cu(II) complexes of the two Schiff bases were screened for antibacterial activities by the disk diffusion method. The antibacterial activity was screened using Escherichia coli and Staphylococcus capitis but the antifungal activity was examined by using Aspergillus flavus and Candida albicans. The Results showed that the tested complexes have antibacterial, except CuH4L, but not antifungal activities.

  13. Cytotoxic and Antifungal Constituents Isolated from the Metabolites of Endophytic Fungus DO14 from Dendrobium officinale

    Directory of Open Access Journals (Sweden)

    Ling-Shang Wu

    2015-12-01

    Full Text Available Two novel cytotoxic and antifungal constituents, (4S,6S-6-[(1S,2R-1, 2-dihydroxybutyl]-4-hydroxy-4-methoxytetrahydro-2H-pyran-2-one (1, (6S,2E-6-hydroxy-3-methoxy-5-oxodec-2-enoic acid (2, together with three known compounds, LL-P880γ (3, LL-P880α (4, and Ergosta-5,7,22-trien-3b-ol (5 were isolated from the metabolites of endophytic fungi from Dendrobium officinale. The chemical structures were determined based on spectroscopic methods. All the isolated compounds 1–5 were evaluated by cytotoxicity and antifungal effects. Our present results indicated that compounds 1–4 showed notable anti-fungal activities (minimal inhibitory concentration (MIC ≤ 50 μg/mL for all the tested pathogens including Candida albicans, Cryptococcus neoformans, Trichophyton rubrum, Aspergillus fumigatus. In addition, compounds 1–4 possessed notable cytotoxcities against human cancer cell lines of HL-60 cells with the IC50 values of below 100 μM. Besides, compounds 1, 2, 4 and 5 showed strong cytotoxities on the LOVO cell line with the IC50 values were lower than 100 μM. In conclusion, our study suggested that endophytic fungi of D. officinale are great potential resources to discover novel agents for preventing or treating pathogens and tumors.

  14. Chemical and Biological Characterization of Oleanane Triterpenoids from Soy

    Directory of Open Access Journals (Sweden)

    David G. Popovich

    2009-08-01

    Full Text Available Soyasaponins are a group of complex and structural diverse oleanane triterpenoids found in soy (Glycine max and other legumes. They are primarily classified into two main groups − group A and B − based on the attachment of sugar moieties at positions C-3 and C-22 of the ring structures. Group A soyasaponins are bidesmosidic, while group B soyasaponins are monodesmosidic. Group B soyasaponins are further classified into two subcategories known as 2,3-dihydro-2,5-dihydroxy-6 -methyl-4H-pyran-4-one (DDMP and non-DDMP conjugated molecules. The preparation and purification of soyasaponin molecules is complicated by the presence of bioactive soy isoflavones, which often overlap with soyasaponin in polarity and must removed from extracts before biological assessment. Soyasaponin extracts, aglycones of group A and B and individual group B soyasaponins such as soyasaponin I have been reported to posses specific bioactive properties, such as in vitro anti-cancer properties by modulating the cell cycle and inducing apoptosis. The isolation, chemical characterization and detection strategies by HPLC and HPLC-MS are reviewed, along with the reported bioactive effects of soyasaponin extracts and individual molecules in cultured cancer cell experiments.

  15. Intramolecular hydroalkoxylation of non-activated C=C bonds catalysed by zeolites: an experimental and theoretical study.

    Science.gov (United States)

    Pérez-Mayoral, Elena; Matos, Ines; Nachtigall, Petr; Položij, Miroslav; Fonseca, Isabel; Vitvarová-Procházková, Dana; Čejka, Jiří

    2013-06-01

    The high activity and selectivity of zeolites in the cyclisation of unsaturated alcohols is reported for the first time; the details of a reaction mechanism based on quantum chemical calculations are also provided. The high efficiency of zeolites MFI, BEA and FAU in the cyclisation of unsaturated alcohols (cis-decen-1-ol, 6-methylhept-5-en-2-ol and 2-allylphenol) to afford oxygen-containing heterocyclic rings is demonstrated. The best catalytic performance is found for zeolites with the optimum concentration of Brønsted acid sites (ca. 0.2 mmol g(-1)) and the minimum number of Lewis acid sites. It is proposed that the efficiency of the catalysts is reduced by the existence of the so-called dual site, at which a molecule of unsaturated alcohol can simultaneously interact with two acid sites (an OH group with one and the double bond with the other Brønsted site), which increases the interaction strength. The formation of such adsorption complexes leads to a decrease in the catalyst activity because of (i) an increase in the reaction barrier, (ii) an unfavourable conformation and (iii) diffusion limitations. A new procedure for the preparation of tetrahydrofurans and pyrans over zeolite catalysts provides important oxygen-containing heterocycles with numerous applications.

  16. Crystal structure of 2-methylamino-4-(6-methyl-4-oxo-4H-chromen-3-yl-3-nitropyrano[3,2-c]chromen-5(4H-one with an unknown solvate

    Directory of Open Access Journals (Sweden)

    Rajamani Raja

    2015-09-01

    Full Text Available In the title compound, C23H16N2O7, the mean planes of the two chromene units (r.m.s. deviations = 0.031 and 0.064 Å are almost normal to one another with a dihedral angle of 85.59 (6°. The central six-membered pyran ring has a distorted envelope conformation, with the methine C atom at the flap. There is an intramolecular N—H...O hydrogen bond, which generates an S(6 ring motif. In the crystal, molecules are linked by pairs of N—H...O hydrogen bonds, forming inversion dimers with an R22(12 ring motif. The dimers are linked by pairs of C—H...O hydrogen bonds, enclosing R22(6 ring motifs, forming zigzag chains along [001]. The chains are linked by a second pair of C—H...O hydrogen bonds, forming slabs parallel to (110. Within the slabs there are C—H...π interactions present. A region of disordered electron density was treated with the SQUEEZE procedure in PLATON [Spek (2015. Acta Cryst. C71, 9–18] following unsuccessful attempts to model it as plausible solvent molecule(s. The given chemical formula and other crystal data do not take into account the unknown solvent molecule(s.

  17. Total synthesis, assignment of the relative and absolute stereochemistry, and structural reassignment of phostriecin (aka Sultriecin).

    Science.gov (United States)

    Burke, Christopher P; Haq, Nadia; Boger, Dale L

    2010-02-24

    A total synthesis of phostriecin (2), previously known as sultriecin (1), its structural reassignment as a phosphate versus sulfate monoester, and the assignment of its relative and absolute stereochemistry are disclosed herein. Key elements of the work, which provided first the originally assigned sulfate monoester 1 and then the reassigned and renamed phosphate monoester 2, relied on diagnostic (1)H NMR spectroscopic properties of the natural product for the assignment of relative and absolute stereochemistry as well as the subsequent structural reassignment, and a convergent asymmetric total synthesis to provide the unequivocal authentic materials. Key steps of the synthetic approach include a Brown allylation for diastereoselective introduction of the C9 stereochemistry, an asymmetric CBS reduction to establish the lactone C5-stereochemistry, diastereoselective oxidative ring expansion of an alpha-hydroxyfuran to access the pyran lactone precursor, and single-step installation of the sensitive Z,Z,E-triene unit through a chelation-controlled cuprate addition with installation of the C11 stereochemistry. The approach allows ready access to analogues that can now be used to probe important structural features required for protein phosphatase 2A inhibition, the mechanism of action defined herein.

  18. Enantioselective Organocatalyzed Synthesis of 2-Amino-3-cyano-4H-chromene Derivatives

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    Isaac G. Sonsona

    2015-08-01

    Full Text Available The structural motif that results from the fusion of a benzene ring to a heterocyclic pyran ring, known as chromene, is broadly found in nature and it has been reported to be associated with a wide range of biological activity. Moreover, asymmetric organocatalysis is a discipline in expansion that is already recognized as a well-established tool for obtaining enantiomerically enriched compounds. This review covers the particular case of the asymmetric synthesis of 2-amino-3-cyano-4H-chromenes using organocatalysis. Herein, we show the most illustrative examples of the methods developed by diverse research groups, following a classification based on these five different approaches: (1 addition of naphthol compounds to substituted α,α-dicyanoolefins; (2 addition of malononitrile to substituted o-vinylphenols; (3 addition of malononitrile to N-protected o-iminophenols; (4 Michael addition of nucleophiles to 2-iminochromene derivatives; and (5 organocatalyzed formal [4+2] cycloaddition reaction. In most cases, chiral thioureas have been found to be effective catalysts to promote the synthetic processes, and generally a bifunctional mode of action has been envisioned for them. In addition, squaramides and cinchona derivatives have been occasionally used as suitable catalysts for the substrates activation.

  19. Evaluation of Extraction and Degradation Methods to Obtain Chickpeasaponin B1 from Chickpea (Cicer arietinum L.).

    Science.gov (United States)

    Cheng, Kun; Gao, Hua; Wang, Rong-Rong; Liu, Yang; Hou, Yu-Xue; Liu, Xiao-Hong; Liu, Kun; Wang, Wei

    2017-02-21

    The objective of this research is to implement extraction and degradation methods for the obtainment of 3-O-[α-l-rhamnopyranosyl-(1→2)-β-d-galactopyranosyl] soyasapogenol B (chickpeasaponin B1) from chickpea. The effects of microwave-assisted extraction (MAE) processing parameters-such as ethanol concentration, solvent/solid ratio, extraction temperature, microwave irradiation power, and irradiation time-were evaluated. Using 1g of material with 8 mL of 70% aqueous ethanol and an extraction time of 10 min at 70 °C under irradiation power 400W provided optimal extraction conditions. Compared with the conventional extraction techniques, including heat reflux extraction (HRE), Soxhlet extraction (SE), and ultrasonic extraction (UE), MAE produced higher extraction efficiency under a lower extraction time. DDMP (2,3-dihydro-2,5-dihydroxy-6-methyl-4H-pyran-4-one) saponin can be degraded to structurally stable saponin B by the loss of its DDMP group. The influence of pH and the concentration of potassium hydroxide on transformation efficiency of the target compound was investigated. A solution of 0.25 M potassium hydroxide in 75% aqueous ethanol was suitable for converting the corresponding DDMP saponins of chickpeasaponin B1. The implementation by the combining MAE technique and alkaline hydrolysis method for preparing chickpeasaponin B1 provides a convenient technology for future applications.

  20. Produtos naturais da ascídia Botrylloides giganteum, das esponjas Verongula gigantea, Ircinia felix, Cliona delitrix e do nudibrânquio Tambja eliora, da costa do Brasil Natural products from the ascidian Botrylloides giganteum, from the sponges Verongula gigantea, Ircinia felix, Cliona delitrix and from the nudibranch Tambja eliora, from the Brazilian coastline

    Directory of Open Access Journals (Sweden)

    Ana Claudia Granato

    2005-03-01

    Full Text Available Two new marine metabolites, 3Z, 6Z, 9Z-dodecatrien-1-ol (1 from the ascidian Botrylloides giganteum and 4H-pyran-2ol acetate from the sponge Ircinia felix (4 are herein reported. The known bromotyrosine compounds, 2-(3,5-dibromo-4-methoxyphenyl-N,N,N-dimethylethanammonium (2 and 2,6-dibromo-4-(2-(trimethylammoniumethylphenol (3, have been isolated from the sponge Verongula gigantea. Serotonin (5 is reported for the first time from the sponge Cliona delitrix, and tambjamines A (15 and D (16 isolated as their respective salts from the nudibranch Tambja eliora. Only tambjamine D presented cytotoxicity against CEM (IC50 12.2 µg/mL and HL60 (IC50 13.2 µg/mL human leukemya cells, MCF-7 breast cancer cells (IC50 13.2 µg/mL, colon HCT-8 cancer cells (IC50 10.1 µg/mL and murine melanoma B16 cancer cells (IC50 6.7 µg/mL.

  1. Crystal structure of 6-bromo-7-fluoro-4-oxo-4H-chromene-3-carbaldehyde

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    Yoshinobu Ishikawa

    2015-07-01

    Full Text Available In the title compound, C10H4BrFO3, a brominated and fluorinated 3-formylchromone derivative, all atoms are essentially coplanar (r.m.s. deviation of 0.025 Å for the non-H atoms, with the largest deviation from the least-squares plane [0.050 (6 Å] being for a benzene-ring C atom. In the crystal, molecules are linked through stacking interactions [centroid–centroid distance between the benzene and pyran rings = 3.912 (4 Å], C—H...O hydrogen bonds and short C...O contacts [2.865 (7 Å]. Unsymmetrical halogen...halogen interactions between the bromine and fluorine atoms [Br...F = 3.116 (4 Å, C—Br...F = 151.8 (2, C—F...Br = 154.1 (4°] are also formed, giving a meandering two-dimensional network propagating in the (041 plane. A comparison with related structures is made and the various types of weak interactions are ranked in importance.

  2. Crystal structure of 8-bromo-4-oxo-4H-chromene-3-carbaldehyde

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    Yoshinobu Ishikawa

    2015-08-01

    Full Text Available In the title compound, C10H5BrO3, a brominated 3-formylchromone, all atoms are essentially coplanar (r.m.s. = 0.0104 Å for the non-H atoms, with the largest deviation from the least-squares plane [0.028 (5 Å] being for one of the benzene C atoms. In the crystal, molecules are linked through C—H...O hydrogen bonds, which are further assembled by face-to-face π–π stacking interactions [centroid–centroid distance between the pyran rings = 3.854 (4 Å]. Shorter contacts than the sum of van der Waals radii are observed between the Br and formyl O atoms [Br...O = 3.046 (4 Å, C—Br...O = 175.23 (18° and Br...O—C = 132.6 (3°], features that do indicate halogen bonding.

  3. Crystal structure of 6,7-dichloro-4-oxo-4H-chromene-3-carbaldehyde

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    Yoshinobu Ishikawa

    2015-09-01

    Full Text Available In the title compound, C10H4Cl2O3, a dichlorinated 3-formylchromone, the non-H atoms of the 4H-chromene ring are essentially coplanar (r.m.s. = 0.0188 Å, with the largest deviation from the least-squares plane [0.043 (2 Å] being for the pyran C=O C atom. The α,β-unsaturated carbonyl O atom deviates from the least-square plane by 0.124 (2 Å. The dihedral angle between the chromone and formyl least-square planes is 6.76 (3°. In the crystal, molecules are linked through C—H...O hydrogen bonds between the translation-symmetry and inversion-symmetry equivalents to form tetrads, which are further assembled by stacking interactions [centroid–centroid distance between the benzene rings = 3.769 (2 Å]. van der Waals contacts are found between the Cl atoms at the 6-position and the Cl atoms at 7-position of the glide-reflection-symmetry equivalents [Cl...Cl = 3.4785 (16 Å, C—Cl...Cl = 160.23 (7° and Cl...Cl—C = 122.59 (7°].

  4. InCl3·4H2O Promoted Green Preparation of Xanthenedione Derivatives in Ionic Liquids

    Institute of Scientific and Technical Information of China (English)

    HU Xue-yuan; ZHANG Xin-ying; FAN Xue-sen; WANG Jian-ji

    2004-01-01

    Xanthenediones derivatives have attracted considerable interests in recent times because they constitute a structural unit in a number of natural products1 and have been used as versatile synthons due to the inherent reactivity of the inbuilt pyran ring2. The conventional syntheses of xanthenediones were acid or base catalyzed condensation of appropriate active methylene carbonyl compounds with aldehydes3. However, many of these procedures involved longer reaction times,low yields and side reactions of aldehydes. In recent years, room temperature ionic liquids (RTILs) have been used as novel green reaction media4. Considering that InCl3 is an efficient Lewis acid catalyst used in promoting many organic reactions, especially in several condensation processes, we herein wish to report a very simple and green method for the preparation of poly-hydrogenated xanthenediones through InCl3·4H2O promoted cascade reaction of aldehydes and 5,5-dimethyl-l,3-cyclohexanedione in ionic liquid,1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][BF4]). The preparative process presented here is operationally simple, environmentally benign and has the advantage of enhanced atom utilization. Furthermore, the solvent and the catalyst used can be recovered easily and reused efficiently.

  5. The Study of Kinetic Properties and Analytical Pyrolysis of Coconut Shells

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    Mahir Said

    2015-01-01

    Full Text Available The kinetic properties of coconut shells during pyrolysis were studied to determine its reactivity in ground form. The kinetic parameters were determined by using thermogravimetric analyser. The activation energy was 122.780 kJ/mol. The pyrolysis products were analyzed using pyrolysis gas chromatography/mass spectrometry (Py-GC/MS. The effects of pyrolysis temperature on the distribution of the pyrolytic products were assessed in a temperature range between 673 K and 1073 K. The set time for pyrolysis was 2 s. Several compounds were observed; they were grouped into alkanes, acids, ethers and alcohols, esters, aldehydes and ketones, furans and pyrans, aromatic compounds, and nitrogen containing compounds. The product compositions varied with temperature in that range. The highest gas proportion was observed at high temperature while the acid proportion was observed to be highest in coconut shells, thus lowering the quality of bio-oil. It has been concluded that higher pyrolysis temperature increases the amount of pyrolysis products to a maximum value. It has been recommended to use coconut shell for production of gas, instead of production of bio-oil due to its high proportion of acetic acid.

  6. Cytotoxic and Antifungal Constituents Isolated from the Metabolites of Endophytic Fungus DO14 from Dendrobium officinale.

    Science.gov (United States)

    Wu, Ling-Shang; Jia, Min; Chen, Ling; Zhu, Bo; Dong, Hong-Xiu; Si, Jin-Ping; Peng, Wei; Han, Ting

    2015-12-22

    Two novel cytotoxic and antifungal constituents, (4S,6S)-6-[(1S,2R)-1, 2-dihydroxybutyl]-4-hydroxy-4-methoxytetrahydro-2H-pyran-2-one (1), (6S,2E)-6-hydroxy-3-methoxy-5-oxodec-2-enoic acid (2), together with three known compounds, LL-P880γ (3), LL-P880α (4), and Ergosta-5,7,22-trien-3b-ol (5) were isolated from the metabolites of endophytic fungi from Dendrobium officinale. The chemical structures were determined based on spectroscopic methods. All the isolated compounds 1-5 were evaluated by cytotoxicity and antifungal effects. Our present results indicated that compounds 1-4 showed notable anti-fungal activities (minimal inhibitory concentration (MIC) ≤ 50 μg/mL) for all the tested pathogens including Candida albicans, Cryptococcus neoformans, Trichophyton rubrum, Aspergillus fumigatus. In addition, compounds 1-4 possessed notable cytotoxcities against human cancer cell lines of HL-60 cells with the IC50 values of below 100 μM. Besides, compounds 1, 2, 4 and 5 showed strong cytotoxities on the LOVO cell line with the IC50 values were lower than 100 μM. In conclusion, our study suggested that endophytic fungi of D. officinale are great potential resources to discover novel agents for preventing or treating pathogens and tumors.

  7. Separation and identification of hydrocarbons and other volatile compounds from cultures of Aspergillus niger by GC–MS using two different capillary columns and solvents

    Directory of Open Access Journals (Sweden)

    Shafiquzzaman Siddiquee

    2015-05-01

    Full Text Available A simple, fast, repeatable, and less laborious sample-preparation protocol based on gas chromatography–mass spectrometry was developed and applied for the analysis of bioactive compounds derived from the filamentous fungus Aspergillus niger strain SS10. The match factors for the spectra of the samples with reference to the mass-spectral library of fungal volatile compounds were determined and used to study the complex hydrocarbons and other volatile compounds that were separated using two different capillary columns and nonpolar and medium-polar stationary phases. More than 295 volatile compounds (spectral match factor of at least 90%, such as normal saturated hydrocarbons (C7–C30, cyclohexane, cyclopentane, fatty acids, alcohols, esters, sulfur- and bromo-containing compounds, simple pyrane, and benzene derivatives, were identified. Most of these compounds have not been reported earlier. The method described in this article is a suitable research tool for the determination of volatile compounds from the cultures of A. niger.

  8. Ultra-broad range organic solid-state laser from a dye-doped holographic grating quasi-waveguide configuration

    Science.gov (United States)

    Liu, Minghuan; Liu, Yonggang; Peng, Zenghui; Mu, Quanquan; Cao, Zhaoliang; Lu, Xinghai; Ma, Ji; Xuan, Li

    2017-08-01

    This paper reports the ultra-broad 149.1 nm lasing emission from 573.2 to 722.3 nm using a simple [4-(dicyanomethylene)-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran] (DCM)-doped holographic polymer-dispersed liquid crystal (HPDLC) grating quasi-waveguide configuration by varying the grating period. The lasing emission beams show s-polarization property. The quasi-waveguide structure, which contained the cover glass, the DCM-doped HPDLC grating, the semiconducting polymer film poly[-methoxy-5-(2‧-ethyl-hexyloxy)-1,4-phenylene-vinylene] (MEH-PPV), and the substrate were confirmed to decrease lasing threshold and broaden lasing wavelength. The operational lifetime of the device is 240 000 pulses, which corresponds to an overall laser duration of more than 6 h at a repetition rate of 10 Hz. In addition, the dual-wavelength lasing range from the 8th and 9th order is over 40 nm. The electrical tunability of the dual-wavelength lasing emission is over 1 nm. The experimental results facilitated the decreased lasing threshold and broadened lasing wavelength range of organic solid-state lasers.

  9. Synthesis, spectroscopic characterization and crystallographic behavior of a biologically relevant novel indole-fused heterocyclic compound - Experimental and theoretical (DFT) studies

    Science.gov (United States)

    Sharma, Sakshi; Brahmachari, Goutam; Banerjee, Bubun; Nurjamal, Khondekar; Kumar, Abhishek; Srivastava, Ambrish Kumar; Misra, Neeraj; Pandey, Sarvesh Kumar; Rajnikant; Gupta, Vivek K.

    2016-08-01

    The present communication deals with the eco-friendly synthesis, spectral properties and X-ray crystal structure of an indole derivative - Ethyl 2'-amino-3'-cyano-6'-methyl-5-nitro-2-oxospiro [indoline-3,4'-pyran]-5'-carboxylate. The title compound was synthesized in 87% yield. The crystal structure of the molecule is stabilized by intermolecular Nsbnd H … N, Nsbnd H … O and Csbnd H … π interactions. The molecule is organized in the crystal lattice forming sheet like structure. To interpret the experimental data, ab initio computations of the vibrational frequencies were carried out using the Gaussian 09 program followed by the full optimizations done using Density Functional Theory (DFT) at B3LYP/6-31 + G(d,p) level. The combined use of experiments and computations allowed a firm assignment of the majority of observed bands for the compound. The calculated highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) with frontier orbital gap were presented. The electronic and charge transfer properties have been explained on the basis of highest occupied molecular orbitals (HOMOs), lowest unoccupied molecular orbitals (LUMOs) and density of states (DOS). From the optimized geometry of the molecule, molecular electrostatic potential (MEP) distribution, frontier molecular orbitals (FMOs) of the title compound have been calculated in the ground state theoretically. The theoretical results showed good agreement with the experimental values. First hyperpolarizability values have been calculated to describe the nonlinear optical (NLO) property of the synthesized compound.

  10. Highly Bright White Organic Light-Emitting Diode

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@ A highly bright white organic light-emitting diode (OLED) was realized by using a highly bright blue emitting layer, 1,7-diphenyl-4-biphenyl-3,5-dimethyl-l,7-dihydrodipyrazolo[3,4-b;4',3'-e]pyridine (PAP-Ph), together with a 4-(dicyanomethylene)-2-methyl-6-(4-dimethylaminostyryl)-4H-pyran (DCM)-doped Alq [tris(8-hydroxyquinolinato) aluminum (Ⅲ)] layer to provide the blue, red and green emission for color mixing. With appropriate thickness control, the white-light OLED has a performance that reaches 24700 cd/m2 at 15 V, 1.93 lm/W at 6.5 V, and >300 cd/m2 at 7.7 mA/em2. The Commission Internationale de l'Eclairage (CIE) coordinates of the emitted light vary in a very small range, from (0.35, 0.34) to (0.34, 0.35), when forward voltages change from 6 to 12 V.

  11. Highly Bright White Organic Light-Emitting Diode

    Institute of Scientific and Technical Information of China (English)

    KO; C.; W.

    2001-01-01

    A highly bright white organic light-emitting diode (OLED) was realized by using a highly bright blue emitting layer, 1,7-diphenyl-4-biphenyl-3,5-dimethyl-l,7-dihydrodipyrazolo[3,4-b;4',3'-e]pyridine (PAP-Ph), together with a 4-(dicyanomethylene)-2-methyl-6-(4-dimethylaminostyryl)-4H-pyran (DCM)-doped Alq [tris(8-hydroxyquinolinato) aluminum (Ⅲ)] layer to provide the blue, red and green emission for color mixing. With appropriate thickness control, the white-light OLED has a performance that reaches 24700 cd/m2 at 15 V, 1.93 lm/W at 6.5 V, and >300 cd/m2 at 7.7 mA/em2. The Commission Internationale de l'Eclairage (CIE) coordinates of the emitted light vary in a very small range, from (0.35, 0.34) to (0.34, 0.35), when forward voltages change from 6 to 12 V.  ……

  12. Study of the contribution of massoia lactone to the aroma of Merlot and Cabernet Sauvignon musts and wines.

    Science.gov (United States)

    Pons, Alexandre; Allamy, Lucile; Lavigne, Valérie; Dubourdieu, Denis; Darriet, Philippe

    2017-10-01

    Organic extracts of musts and red wines marked by dried fruit and cooked fruit aromas were analyzed by gas chromatography coupled to olfactometry and mass spectrometry. Thanks to this analytical approach we identified a fragrant lactone corresponding to an odorant zone reminiscent of coconut and dried figs as 5,6-dihydro-6-pentyl-2H-pyran-2-one (C10 massoia lactone). Using chiral GC-GC-MS, we show that only the (R)-C10 massoia lactone is found in musts and wines. Its detection thresholds were 10µg/L and 11µg/L in must and wine model solution, respectively. In Merlot and Cabernet Sauvignon musts marked by dried fruit flavors from overripe grapes, its concentration reached 68µg/L. In contrast, in wines marked by these flavors, it never exceeded 20µg/L. We show that (R)-C10 massoia lactone is reduced to (R)-δ-decalactone during alcoholic fermentation. In addition, we underline the contribution of temperature during the growing season on its level in old red wines. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Natural products from the ascidian Botrylloides giganteum, from the sponges Verongula gigantea, Ircinia felix, Cliona delitrix and from the nudibranch Tambja eliora, from the Brazilian coastline; Produtos naturais da ascidia Botrylloides giganteum, das esponjas Verongula gigantea, Ircinia felix, Cliona delitrix e do nudibranquio Tambja eliora, da costa do Brasil

    Energy Technology Data Exchange (ETDEWEB)

    Granato, Ana Claudia; Oliveira, Jaine H.H.L. de; Seleghim, Mirna H.R.; Berlinck, Roberto G.S. [Sao Paulo Univ., Sao Carlos, SP (Brazil). Inst. de Quimica]. E-mail: rgsberlinck@iqsc.usp.br; Macedo, Mario L.; Ferreira, Antonio G. [Sao Carlos Univ., SP (Brazil). Dept. de Quimica; Rocha, Rosana M. da [Parana Univ., Curitiba, PR (Brazil). Setor de Ciencias Biologicas. Dept. de Zoologia; Hajdu, Eduardo [Universidade Federal, Rio de Janeiro, RJ (Brazil). Museu Nacional; Peixinho, Solange [Bahia Univ., Salvador, BA (Brazil). Dept. de Biologia; Pessoa, Claudia O.; Moraes, Manoel O.; Cavalcanti, Bruno C. [Ceara Univ., Fortaleza, CE (Brazil). Dept. de Fisiologia e Farmacologia

    2005-04-01

    Two new marine metabolites, 3Z, 6Z, 9Z-dodecatrien-1-ol (1) from the ascidian Botrylloides giganteum and 4H-pyran-2ol acetate from the sponge Ircinia felix (4) are herein reported. The known bromotyrosine compounds, 2-(3,5-dibromo-4-methoxyphenyl)-N,N,Ndimethylethanammonium (2) and 2,6-dibromo-4-(2-(trimethylammonium)ethyl)phenol (3), have been isolated from the sponge Verongula gigantea. Serotonin (5) is reported for the first time from the sponge Cliona delitrix, and tambjamines A (15) and D (16) isolated as their respective salts from the nudibranch Tambja eliora. Only tambjamine D presented cytotoxicity against CEM (IC{sub 5})0 12.2 {mu}g/mL) and HL60 (IC{sub 50} 13.2 {mu}g/mL) human leukemia cells, MCF-7 breast cancer cells (IC{sub 50} 13.2 {mu}g/mL), colon HCT-8 cancer cells (IC{sub 50} 10.1 {mu}g/mL) and murine melanoma B16 cancer cells (IC{sub 50} 6.7 {mu}g/mL). (author)

  14. Microstructure, morphology, and ultrafast dynamics of a novel edible microemulsion.

    Science.gov (United States)

    Saha, Ranajay; Rakshit, Surajit; Mitra, Rajib Kumar; Pal, Samir Kumar

    2012-06-05

    An edible microemulsion (ME) composed of Tween 80/butyl lactate/isopropyl myristate (IPM)/water has been formulated. Pseudoternary phase diagram of the system contains a large single isotropic region. The phase behavior of the system is also studied at low pH (2.6) and in 0.9% NaCl solution. Conductivity, viscosity, ultrasonic velocity, and compressibility studies find consistent results in the structural transition (from water-in-oil (w/o) to bicontinuous, and from bicontinuous to oil-in-water (o/w)) behavior of the ME. Dynamic light scattering studies reveal the size of the MEs. The absorption and steady state emission spectra of 4-(dicyanomethylene)-2-methyl-6-(p-dimethylamino-styryl)-4H-pyran (DCM) successfully probe the polarity of the ME at its solvation shell and shows the efficacy of hosting model drug molecules. The rotational anisotropy of the dye has been studied to ascertain the geometrical restriction of the probe molecule. Picosecond-resolved fluorescence spectroscopy applies well to study the relaxation dynamics of water in the solvation shell of the MEs. The study finds strong correlation in the relaxation dynamics of water with the structure of host assembly and offers an edible ME system which could act as a potential drug delivery system and nontoxic nanotemplate for other applications.

  15. Analysis of liquid and solid products from liquefaction of paulownia in hot-compressed water

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Peiqin; Heng, Mingxing; Sun, Shao-Hui; Chen, Junwu [School of Chemical and Energy Engineering, Zhengzhou University, Zhengzhou 450001 (China)

    2011-02-15

    Biomass has been proposed to be an alternative source of fuels for industrial applications. The liquefaction of paulownia was studied in hot-compressed water with iron catalyst at temperatures ranging from 280 to 360 C, using a 1000 ml stainless steel autoclave with a magnetic stirrer. With an increase of the reaction temperature, the yield of heavy oil increased and then decreased. The maximum yield of heavy oil of 36.34 wt.% was obtained at 340 C. The experimental results show that the reaction temperature significantly influenced the process of biomass liquefaction. The liquid products and solid residues produced at various reaction temperatures were analyzed using Fourier transform infrared (FTIR) spectrophotometer and the heavy oil got at 340 C were analyzed using gas chromatograph with mass selective detector (GC-MS), respectively. The analytical results show that the heavy oil and water-soluble oil is complicated compound. The water-soluble oil mainly contains carbohydrates, acetic acid, alcohols, aldehydes and pyran derivatives. In addition, the heavy oil mainly consists of phenol and its derivatives, ketone, long-chain carboxylic acids/esters, benzene derivatives and long-chain alkanes. (author)

  16. Analysis of liquid and solid products from liquefaction of paulownia in hot-compressed water

    Energy Technology Data Exchange (ETDEWEB)

    Sun Peiqin; Heng Mingxing [School of Chemical and Energy Engineering, Zhengzhou University, Zhengzhou 450001 (China); Sun Shaohui, E-mail: hengjim@hotmail.co [School of Chemical and Energy Engineering, Zhengzhou University, Zhengzhou 450001 (China); Chen Junwu [School of Chemical and Energy Engineering, Zhengzhou University, Zhengzhou 450001 (China)

    2011-02-15

    Biomass has been proposed to be an alternative source of fuels for industrial applications. The liquefaction of paulownia was studied in hot-compressed water with iron catalyst at temperatures ranging from 280 to 360 {sup o}C, using a 1000 ml stainless steel autoclave with a magnetic stirrer. With an increase of the reaction temperature, the yield of heavy oil increased and then decreased. The maximum yield of heavy oil of 36.34 wt.% was obtained at 340 {sup o}C. The experimental results show that the reaction temperature significantly influenced the process of biomass liquefaction. The liquid products and solid residues produced at various reaction temperatures were analyzed using Fourier transform infrared (FTIR) spectrophotometer and the heavy oil got at 340 {sup o}C were analyzed using gas chromatograph with mass selective detector (GC-MS), respectively. The analytical results show that the heavy oil and water-soluble oil is complicated compound. The water-soluble oil mainly contains carbohydrates, acetic acid, alcohols, aldehydes and pyran derivatives. In addition, the heavy oil mainly consists of phenol and its derivatives, ketone, long-chain carboxylic acids/esters, benzene derivatives and long-chain alkanes.

  17. Evaluation of Extraction and Degradation Methods to Obtain Chickpeasaponin B1 from Chickpea (Cicer arietinum L.

    Directory of Open Access Journals (Sweden)

    Kun Cheng

    2017-02-01

    Full Text Available The objective of this research is to implement extraction and degradation methods for the obtainment of 3-O-[α-l-rhamnopyranosyl-(1→2-β-d-galactopyranosyl] soyasapogenol B (chickpeasaponin B1 from chickpea. The effects of microwave-assisted extraction (MAE processing parameters—such as ethanol concentration, solvent/solid ratio, extraction temperature, microwave irradiation power, and irradiation time—were evaluated. Using 1g of material with 8 mL of 70% aqueous ethanol and an extraction time of 10 min at 70 °C under irradiation power 400W provided optimal extraction conditions. Compared with the conventional extraction techniques, including heat reflux extraction (HRE, Soxhlet extraction (SE, and ultrasonic extraction (UE, MAE produced higher extraction efficiency under a lower extraction time. DDMP (2,3-dihydro-2,5-dihydroxy-6-methyl-4H-pyran-4-one saponin can be degraded to structurally stable saponin B by the loss of its DDMP group. The influence of pH and the concentration of potassium hydroxide on transformation efficiency of the target compound was investigated. A solution of 0.25 M potassium hydroxide in 75% aqueous ethanol was suitable for converting the corresponding DDMP saponins of chickpeasaponin B1. The implementation by the combining MAE technique and alkaline hydrolysis method for preparing chickpeasaponin B1 provides a convenient technology for future applications.

  18. Photoerasing paper and thermocoloring film

    Science.gov (United States)

    Kanakkanatt, Sebastian V.

    1997-08-01

    Thermal coloration of spiropyrans and spiroxazines at or above their melting point is well known to photochromists. The erasure of the color developed by exposure of photochromic paper by radiations of certain wavelengths in the visible region is little known. Six-nitrospirobenzopyran and 8- nitrospirobenzopyran, 8-methoxy-6-nitrospirobenzo-pyran, 6- methoxy-8-nitrospirobenzopyran, and 6,8-dinitrospirobenzopyran have been studied. The medium in which these photochromic dyes were dissolved or incorporated was limited to cellulose derivatives such as cellulose acetate, cellulose acetate- butyrate, and cellulose trinitrate. Paper coated with 6- nitrospirobenzopyran dissolved in an ethyl acetate solution of cellulose trinitrate readily colored on exposure to UV light or IR radiation and faded on exposure to light in the visible range. This unusual phenomenon, although not fully understood, is believed to be a selective light sensitizing ability of nitro groups. The applications of photoerasing paper and thermally colorable films are numerous, such as in polaroid type photography, in copy machines, and in thermally stable photochromic ophthalmic lenses.

  19. Improvement of color purity in white OLED based on Zn(HPB){sub 2} as blue emitting layer

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dong-Eun [Department of Electrical Engineering and NTRC, Dong-A University, Busan, 604-714 (Korea, Republic of); Kim, Won-Sam [Department of Chemistry and Institute of Functional Materials, Inje University, Gimhae, 621-749 (Korea, Republic of); Kim, Byoung-Sang [Department of Electrical Engineering and NTRC, Dong-A University, Busan, 604-714 (Korea, Republic of); Lee, Burm-Jong [Department of Chemistry and Institute of Functional Materials, Inje University, Gimhae, 621-749 (Korea, Republic of); Kwon, Young-Soo [Department of Electrical Engineering and NTRC, Dong-A University, Busan, 604-714 (Korea, Republic of)], E-mail: yskwon@dau.ac.kr

    2008-04-01

    We synthesized zinc (II) [2-(2-hydroxyphenyl)benzoxazole] (Zn(HPB){sub 2}) as blue emitting materials and evaluated in the organic light emitting diodes (OLEDs). The layer of Zn(HPB){sub 2} doped with 4-(dicyanomethylene)-2-t-butyl-6(1,1,7,7-tetramethyljulolidyl-9-enyl) -4H-pyran (DCJTB) (Zn(HPB){sub 2}:DCJTB) as emitters has been demonstrated. The structure of the device is indium-tin-oxide (ITO)/N,N'-bis-(1-naphthl)-diphenyl-1,1'-biphenyl-4,4'-diamine (NPB, 40 nm)/Zn(HPB){sub 2}/Zn(HPB){sub 2}:DCJTB/Alq{sub 3} (20 nm)/LiF/Al. The thickness of Zn(HPB){sub 2} layer was 0, 10, 20, 30 nm at the same time the thickness of Zn(HPB){sub 2}:DCJTB layer were 40, 30, 20, 10 nm. When thickness of Zn(HPB){sub 2} layer was 30 nm and the thickness of Zn(HPB){sub 2}:DCJTB layer was 10 nm, white emission is achieved. The Commission Internationale de l'Eclairage (CIE) coordinates of the white emission are (0.304, 0.332) at an applied voltage of 10.5 V.

  20. Sulfur-containing constituents and one 1H-pyrrole-2-carboxylic acid derivative from pineapple [Ananas comosus (L.) Merr.] fruit.

    Science.gov (United States)

    Zheng, Zong-Ping; Ma, Jinyu; Cheng, Ka-Wing; Chao, Jianfei; Zhu, Qin; Chang, Raymond Chuen-Chung; Zhao, Ming; Lin, Zhi-Xiu; Wang, Mingfu

    2010-12-01

    Two sulfur-containing compounds, (S)-2-amino-5-((R)-1-carboxy-2-((E)-3-(4-hydroxy-3-methoxyphenyl)allylthio)ethyl-amino)-5-oxopentanoic acid (1) and (S)-2-amino-5-((R)-1-(carboxymethylamino)-3-((E)-3-(4-hydroxyphenyl)allylthio)-1-oxopropan-2-ylamino)-5-oxopentanoic acid (2), and one 1H-pyrrole-2-carboxylic acid derivative, 6-(3-(1H-pyrrole-2-carbonyloxy)-2-hydroxypropoxy)-3,4,5-trihydroxy-tetrahydro-2H-pyran-2-carboxylic acid (3), together with eighteen known phenolic compounds, were isolated from the fruits of pineapple. Their structures were elucidated by a combination of spectroscopic analyses. Some of these compounds showed inhibitory activities against tyrosinase. The half maximal inhibitory concentration values of compounds 1, 4, 5, 6, 7 are lower than 1 mM. These compounds may contribute to the well-known anti-browning effect of pineapple juice and be potential skin whitening agents in cosmetic applications.

  1. Chimerical pyrene-based [7]helicenes as twisted polycondensed aromatics.

    Science.gov (United States)

    Buchta, Michal; Rybáček, Jiří; Jančařík, Andrej; Kudale, Amit A; Buděšínský, Miloš; Chocholoušová, Jana Vacek; Vacek, Jaroslav; Bednárová, Lucie; Císařová, Ivana; Bodwell, Graham J; Starý, Ivo; Stará, Irena G

    2015-06-01

    Chimerical pyrene-based dibenzo[7]helicene rac-1 and 2H-pyran[7]helicene (M,R,R)-(-)-2, in which two pyrene subunits are fused to the [7]helicene/[7]heterohelicene scaffold, were synthesised by means of Ni(0) - or Co(I) -mediated [2+2+2] cycloisomerisation of dipyrenyl-acetylene-derived triynes. Pyrene-based dibenzo[7]helicene 1 was obtained in enantioenriched form by enantioselective cycloisomerisation under Ni(0) /QUINAP catalysis (57 % ee) or in enantiopure form by racemate resolution by liquid chromatography on a chiral column. 1,3-Allylic-type strain-controlled diastereoselective cycloisomerisation was employed in the synthesis of enantiopure (M,R,R)-(-)-2. Physicochemical properties of 1 and 2 encompassing the helicity assignment, stability to racemisation, X-ray crystal structure, UV/Vis, experimental/calculated electronic circular dichroism and fluorescence spectra were studied. Accordingly, comparison of the X-ray crystal structure of (M,R,R)-(-)-2 with calculated structures (DFT: B3LYP/cc-pVDZ, B97D/cc-pVDZ) indicated that its helical backbone is slightly over-flattened owing to intramolecular dispersion forces between tert-butylated pyrene subunits. Both 1 and 2 are fluorescent (with quantum yields in dichloromethane of ΦF =0.10 and 0.17, respectively) and are suggested to form intramolecular excimer states upon excitation, which are remarkably stabilised and exhibit large Stokes shifts (296 and 203 nm, respectively).

  2. Flupentixol tartrate.

    Science.gov (United States)

    Yamuna, Thammarse S; Kaur, Manpreet; Anderson, Brian J; Jasinski, Jerry P; Yathirajan, H S

    2014-02-01

    In the title salt, C23H26F3N2OS(+)·C4H5O6 (-) [systematic name: 1-(2-hy-droxy-eth-yl)-4-[3-(2-(tri-fluoro-meth-yl)thioxanthen-9-yl-idene)prop-yl]piperazin-1-ium 3-carb-oxy-2,3-di-hydroxy-pro-pion-ate], the monoprotonated piperazine ring in the cation adopts a chair conformation, while the thio-pyran ring of the thioxanthene group has a boat conformation. The dihedral angle between the mean planes of the two outer aromatic rings of the thioxanthene groups is 31.6 (2)°. In the crystal, the cations and anions are linked via O-H⋯O, N-H⋯O, O-H⋯N and C-H⋯O hydrogen bonds, forming chains propagating along [100]. In addition, R (2) 2(7), R (2) 2(11), R (2) 2(10) and R (2) 2(12) graph-set ring motifs involving the anions, and R (2) 2(9) graph-set ring motifs involving both the cations and anions are observed. The three F atoms of the tri-fluoro-methyl group are disordered over two sets of sites and the individual atoms were refined with occupancy ratios of 0.54 (6):0.46 (6), 0.72 (2):0.28 (2) and 0.67 (3):0.33 (3).

  3. Metabolites of Trichoderma species isolated from damp building materials.

    Science.gov (United States)

    McMullin, David R; Renaud, Justin B; Barasubiye, Tharcisse; Sumarah, Mark W; Miller, J David

    2017-07-01

    Buildings that have been flooded often have high concentrations of Trichoderma spores in the air while drying. Inhaled spores and spore and mycelial fragments contain large amounts of fungal glucan and natural products that contribute to the symptoms associated with indoor mould exposures. In this study, we considered both small molecules and peptaibol profiles of T. atroviride, T. koningiopsis, T. citrinoviride, and T. harzianum strains obtained from damp buildings in eastern Canada. Twenty-residue peptaibols and sorbicillin-derived metabolites (1-6) including a new structure, (R)-vertinolide (1), were characterized from T. citrinoviride. Trichoderma koningiopsis produced several koninginins (7-10), trikoningin KA V, and the 11-residue lipopeptaibols trikoningin KB I and trikoningin KB II. Trichoderma atroviride biosynthesized a mixture of 19-residue trichorzianine-like peptaibols, whereas T. harzianum produced 18-residue trichokindin-like peptaibols and the 11-residue harzianin HB I that was subsequently identified from the studied T. citrinoviride strain. Two α-pyrones, 6-pentyl-pyran-2-one (11) and an oxidized analog (12), were produced by both T. atroviride and T. harzianum. Aside from exposure to low molecular weight natural products, inhalation of Trichoderma spores and mycelial fragments may result in exposure to membrane-disrupting peptaibols. This investigation contributes to a more comprehensive understanding of the biologically active natural products produced by fungi commonly found in damp buildings.

  4. Analysis of commercial proanthocyanidins. Part 2: An electrospray mass spectrometry investigation into the chemical composition of sulfited quebracho (Schinopsis lorentzii and Schinopsis balansae) heartwood extract.

    Science.gov (United States)

    Venter, Pieter B; Senekal, Nadine D; Amra-Jordaan, Maryam; Bonnet, Susan L; Van der Westhuizen, Jan H

    2012-06-01

    Proanthocyanidins (PACs) are natural plant-derived polymers used in leather tanning, wood adhesives, water purification, and mud additives for oil drilling. Quebracho (Schinopsis lorentzii and Schinopsis balansae) heartwood and mimosa (Acacia mearnsii) bark extracts are the major industrial sources of PACs. These commercial extracts are often sulfited via treatment with sodium hydrogen sulfite to reduce their viscosity and increase their solubility in water. An ESI-MS investigation into the molecular composition of sulfited (cold-water-soluble) quebracho heartwood extract indicates that sulfitation of the PACs occurs via S(N)2 attack of a sulfite ion at both C-2 and C-4 of the constituent flavan-3-ol monomer extender units. Attack at C-2 leads to the opening of the pyran ring. This releases an additional electron-donating phenolic hydroxy group on the A-ring and renders the extract more nucleophilic and suitable for the manufacturing of adhesives. Attack at C-4 leads to interflavanyl bond fission and decrease of the PAC oligomer chain length. The introduction of sulfonic acid moieties at C-2 or C-4 increases the polarity and water solubility of the hot water soluble (unsulfited) extract and transforms it into a cold-water-soluble extract.

  5. Solvation dynamics of DCM in a polypeptide-surfactant aggregate: gelatin-sodium dodecyl sulfate.

    Science.gov (United States)

    Halder, Arnab; Sen, Pratik; Burman, Anupam Das; Bhattacharyya, Kankan

    2004-02-03

    Solvation dynamics of 4-(dicyanomethylidene)-2-[p-(dimethylamino)styryl]-6-methyl-4H-pyran (DCM) is studied in a polypeptide-surfactant aggregate consisting of gelatin and sodium dodecyl sulfate (SDS) in potassium dihydrogen phosphate (KP) buffer. The average solvation time (tauS) in gelatin-SDS aggregate at 45 degrees C is found to be 1780 ps, which is about 13 times slower than that in 15 mM SDS in KP buffer at the same temperature. The fluorescence anisotropy decay in gelatin-SDS aggregate is also different from that in SDS micelles in KP buffer. DCM displays negligible emission in the presence of gelatin in aqueous solution. Thus the solvation dynamics in the presence of gelatin and SDS is exclusively due to the probe (DCM) molecules at the gelatin-micelle interface. The slow solvation dynamics is ascribed to the restrictions imposed on the water molecules trapped between the polypeptide chain and micellar aggregates. The critical association concentration (cac) of SDS for gelatin is determined to be 0.5 +/- 0.1 mM.

  6. Phytochemical Profile of Erythrina variegata by Using High-Performance Liquid Chromatography and Gas Chromatography-Mass Spectroscopy Analyses.

    Science.gov (United States)

    Muthukrishnan, Suriyavathana; Palanisamy, Subha; Subramanian, Senthilkumar; Selvaraj, Sumathi; Mari, Kavitha Rani; Kuppulingam, Ramalingam

    2016-08-01

    Natural products derived from plant sources have been utilized to treat patients with numerous diseases. The phytochemical constituents present in ethanolic leaf extract of Erythrina variegata (ELEV) were identified by using high-performance liquid chromatography (HPLC) and gas chromatography-mass spectroscopy (GC-MS) analyses. Shade dried leaves were powdered and extracted with ethanol for analyses through HPLC to identify selected flavonoids and through GC-MS to identify other molecules. The HPLC analysis of ELEV showed the presence of gallic and caffeic acids as the major components at concentrations of 2.0 ppm and 0.1 ppm, respectively, as well as other components. GC-MS analysis revealed the presence of 3-eicosyne; 3,7,11,15-tetramethyl-2-hexadecen-1-ol; butanoic acid, 3-methyl-3,7-dimethyl-6-octenyl ester; phytol; 1,2-benzenedicarboxylic acid, diundecyl ester; 1-octanol, 2-butyl-; squalene; and 2H-pyran, 2-(7-heptadecynyloxy) tetrahydro-derivative. Because pharmacopuncture is a new evolving natural mode that uses herbal extracts for treating patients with various ailments with minimum pain and maximum effect, the results of this study are particularly important and show that ELEV possesses a wide range of phytochemical constituents, as indicated above, as effective active principle molecules that can be used individually or in combination to treat patients with various diseases.

  7. Phytochemical Profile of Erythrina variegata by Using High-Performance Liquid Chromatography and Gas Chromatography-Mass Spectroscopy Analyses

    Directory of Open Access Journals (Sweden)

    Suriyavathana Muthukrishnan

    2016-08-01

    Full Text Available Natural products derived from plant sources have been utilized to treat patients with numerous diseases. The phytochemical constituents present in ethanolic leaf extract of Erythrina variegata (ELEV were identified by using high-performance liquid chromatography (HPLC and gas chromatography-mass spectroscopy (GC-MS analyses. Shade dried leaves were powdered and extracted with ethanol for analyses through HPLC to identify selected flavonoids and through GC-MS to identify other molecules. The HPLC analysis of ELEV showed the presence of gallic and caffeic acids as the major components at concentrations of 2.0 ppm and 0.1 ppm, respectively, as well as other components. GC-MS analysis revealed the presence of 3-eicosyne; 3,7,11,15-tetramethyl-2-hexadecen-1-ol; butanoic acid, 3-methyl-3,7-dimethyl-6-octenyl ester; phytol; 1,2-benzenedicarboxylic acid, diundecyl ester; 1-octanol, 2-butyl-; squalene; and 2H-pyran, 2-(7-heptadecynyloxy tetrahydro-derivative. Because pharmacopuncture is a new evolving natural mode that uses herbal extracts for treating patients with various ailments with minimum pain and maximum effect, the results of this study are particularly important and show that ELEV possesses a wide range of phytochemical constituents, as indicated above, as effective active principle molecules that can be used individually or in combination to treat patients with various diseases.

  8. Crystal Structure of the Streptomyces coelicolor TetR-Like Protein ActR Alone and in Complex with Actinorhodin or the Actinorhodin Biosynthetic Precursor (S)-DNPA

    Energy Technology Data Exchange (ETDEWEB)

    Willems,A.; Tahlan, K.; Taguchi, T.; Zhang, K.; Lee, Z.; Ichinose, K.; Junop, M.; Nodwell, J.

    2008-01-01

    Actinorhodin, an antibiotic produced by Streptomyces coelicolor, is exported from the cell by the ActA efflux pump. actA is divergently transcribed from actR, which encodes a TetR-like transcriptional repressor. We showed previously that ActR represses transcription by binding to an operator from the actA/actR intergenic region. Importantly, actinorhodin itself or various actinorhodin biosynthetic intermediates can cause ActR to dissociate from its operator, leading to derepression. This suggests that ActR may mediate timely self-resistance to an endogenously produced antibiotic by responding to one of its biosynthetic precursors. Here, we report the structural basis for this precursor-mediated derepression with crystal structures of homodimeric ActR by itself and in complex with either actinorhodin or the actinorhodin biosynthetic intermediate (S)-DNPA [4-dihydro-9-hydroxy-1-methyl-10-oxo-3-H-naphtho-[2, 3-c]-pyran-3-(S)-acetic acid]. The ligand-binding tunnel in each ActR monomer has a striking hydrophilic/hydrophobic/hydrophilic arrangement of surface residues that accommodate either one hexacyclic actinorhodin molecule or two back-to-back tricyclic (S)-DNPA molecules. Moreover, our work also reveals the strongest structural evidence to date that TetR-mediated antibiotic resistance may have been acquired from an antibiotic-producer organism.

  9. Unique Polybrominated Hydrocarbons from the Australian Endemic Red Alga Ptilonia australasica.

    Science.gov (United States)

    Tran, Trong D; Pham, Ngoc B; Quinn, Ronald J

    2016-03-25

    The red alga Ptilonia australasica is endemic to Australian temperate waters. Chemical investigation of P. australasica led to the identification of four new polybrominated compounds, ptilones A-C (1-3) and australasol A (4). Their planar structures were established by extensive NMR and MS analyses. The low H/C ratio and the presence of a large number of heteroatoms made the structure elucidation challenging. The absolute configurations of 1, 2, and 4 were determined by quantum chemical ECD calculations employing time-dependent density functional theory. Ptilones A-C (1-3) show unique 4-ethyl-5-methylenecyclopent-2-enone (1 and 2) and 2-methyl-6-vinyl-4H-pyran-4-one (3) skeletons not previously reported in algal metabolites. Ptilone A displayed the most potent cytotoxicity against the human prostate cancer PC3 cells with an IC50 value of 0.44 μM and induced the PC3 cell cycle arrest in the G0/G1 phase.

  10. Minor C-geranylated flavanones from Paulownia tomentosa fruits with MRSA antibacterial activity.

    Science.gov (United States)

    Navrátilová, Alice; Schneiderová, Kristýna; Veselá, Daniela; Hanáková, Zuzana; Fontana, Anna; Dall'Acqua, Stefano; Cvačka, Josef; Innocenti, Gabbriella; Novotná, Jana; Urbanová, Marie; Pelletier, Jerry; Čížek, Alois; Žemličková, Helena; Šmejkal, Karel

    2013-05-01

    Exhaustive chromatographic separation of the chloroform portion of the ethanolic extract obtained from Paulownia tomentosa (Thunb). Steud. (Paulowniaceae) fruits has led to isolation of ten C-6 geranylated flavanones tomentodiplacone C-I and mimulone C-E, featured by 3'-methoxy and 4'-hydroxy or 4'-hydroxy substitution of the B-ring of the flavonoid, respectively. The structures of these compounds were determined by using mass spectrometry (including HRMS) and 1D and 2D NMR spectroscopy. The absolute configurations of the compounds at C-2 were determined using circular dichroism. The obtained compounds showed the presence of a geranyl moiety functionalized by a carbonyl, hydroxyl or methoxyl group, or by formation of tetrahydrofuran or fused-pyrane ring, respectively. All of the flavanones described were isolated for the first time from a natural source. The antibacterial activities of selected compounds isolated along with the previously isolated geranylated flavanones were evaluated against a common panel of microbes and MRSA strains. The selected isolated compounds were tested for their ability to affect eukaryotic translation initiation via dual-luciferase reporter assay (firefly and renilla).

  11. Characterization of Chemical Compounds with Antioxidant and Cytotoxic Activities in Bougainvillea x buttiana Holttum and Standl, (var. Rose) Extracts

    Science.gov (United States)

    Abarca-Vargas, Rodolfo; Peña Malacara, Carlos F.; Petricevich, Vera L.

    2016-01-01

    Bougainvillea is widely used in traditional Mexican medicine to treat several diseases. This study was designed to characterize the chemical constituents of B. x buttiana extracts with antioxidant and cytotoxic activities using different solvents. The extraction solvents used were as follows: distilled water (dH2O), methanol (MeOH), acetone (DMK), ethanol (EtOH), ethyl acetate (EtOAc), dichloromethane (DCM), and hexane (Hex) (100%) at an extraction temperature of 26 °C. Analysis of bioactive compounds present in the B. x buttiana extracts included the application of common phytochemical screening assays, GC-MS analysis, and cytotoxicity and antioxidant assays. The results show that the highest extraction yield was observed with water and methanol. The maximum total phenolic content amount and highest antioxidant potential were obtained when extraction with methanol was used. With the exceptions of water and ethanol extractions, all other extracts showed cytotoxicity ranging between 31% and 50%. The prevailing compounds in water, methanol, ethanol, and acetone solvents were as follows: 4H-pyran-4-one, 2,3-dihydro-3, 5-dihydroxy-6-methyl (2), 2-propenoic acid, 3-(2-hydrophenyl)-(E)- (3), and 3-O-methyl-d-glucose (6). By contrast, the major components in the experiments using solvents such as EtOH, DMK, EtOAc, DCM, and Hex were n-hexadecanoic acid (8), 9,12-octadecadienoic acid (Z,Z) (12); 9-octadecenoic acid (E)- (13), and stigmasta-5,22-dien-3-ol (28). PMID:27918436

  12. The relationship between the violet pigment PP-V production and intracellular ammonium level in Penicillium purpurogenum.

    Science.gov (United States)

    Kojima, Ryo; Arai, Teppei; Matsufuji, Hiroshi; Kasumi, Takafumi; Watanabe, Taisuke; Ogihara, Jun

    2016-12-01

    Penicillium purpurogenum is the fungus that produces an azaphilone pigment. However, details about the pigment biosynthesis pathway are unknown. The violet pigment PP-V is the one of the main pigments biosynthesized by this fungus. This pigment contains an amino group in a pyran ring as its core structure. We focused on this pigment and examined the relationship between intracellular ammonium concentration and pigment production using glutamine as a nitrogen source. The intracellular ammonium level decreased about 1.5-fold in conditions favoring PP-V production. Moreover, P. purpurogenum was transferred to medium in which it commonly produces the related pigment PP-O after cultivating it in the presence or absence of glutamine to investigate whether this fungus biosynthesizes PP-V using surplus ammonium in cells. Only mycelia cultured in medium containing 10 mM glutamine produced the violet pigment, and simultaneously intracellular ammonium levels decreased under this condition. From comparisons of the amount of PP-V that was secreted with quantity of surplus intracellular ammonium, it is suggested that P. purpurogenum maintains ammonium homeostasis by excreting waste ammonium as PP-V.

  13. Glyceollins and dehydroglyceollins isolated from soybean act as SERMs and ER subtype-selective phytoestrogens.

    Science.gov (United States)

    van de Schans, Milou G M; Vincken, Jean-Paul; de Waard, Pieter; Hamers, Astrid R M; Bovee, Toine F H; Gruppen, Harry

    2016-02-01

    Seven prenylated 6a-hydroxy-pterocapans and five prenylated 6a,11a-pterocarpenes with different kinds of prenylation were purified from an ethanolic extract of fungus-treated soybean sprouts. The activity of these compounds toward both human estrogen receptors (hERα and hERβ) was determined in a yeast bioassay and the activity toward hERα was additionally tested in an U2-OS based hERα CALUX bioassay. In the yeast bioassay, compounds with chain prenylation showed in general an agonistic mode of action toward hERα, whereas furan and pyran prenylation led to an antagonistic mode of action. Five of these antagonistic compounds had an agonistic mode of action in the U2-OS based hERα CALUX bioassay, implying that these compounds can act as SERMs. The yeast bioassay also identified 8 ER subtype-selective compounds, with either an antagonistic mode of action or no response toward hERα and an agonistic mode of action toward hERβ. The ER subtype-selective compounds were characterized by 6a-hydroxy-pterocarpan or 6a,11a-pterocarpene backbone structure. It is suggested that either the extra D-ring or the increase in length to 12-13.5Å of these compounds is responsible for an agonistic mode of action toward hERβ and, thereby, inducing ER subtype-selective behavior.

  14. Cloning and characterization of the first polysaccharide lyase family 6 oligoalginate lyase from marine Shewanella sp. Kz7.

    Science.gov (United States)

    Li, Shangyong; Wang, Linna; Han, Feng; Gong, Qianhong; Yu, Wengong

    2016-01-01

    Alginate, the most abundant carbohydrate in brown macroalgae, is widely used in the food and pharmaceutical industries. Recently, alginate has attracted increasing attention, as it may serve as an alternative biomass for the production of biofuel. The degradation of alginate into monomeric units is the prerequisite for bioethanol production. All known oligoalginate lyases belong to the polysaccharide lyase (PL) family 7, 14, 15 and 17, and most of them preferred to degrade the polyM blocks to yield 4-deoxy-l-erythro-5-hexoseulose uronic acid as the primary product. In this study, we cloned an oligoalginate lyase gene, oalS6, from Shewanella sp. Kz7 and expressed it in Escherichia coli. The PL family 6 oligoalginate lyase (OalS6) has no significant sequence similarity with other known oligoalginate lyases. OalS6 contains a chondroitinase-like domain and was assigned to the PL family 6. This lyase is an exo-type oligoalginate lyase and prefer to depolymerize polyG block into 2, 4, 5, 6-tetrahydroxytetrahydro-2H-pyran-2-carboxylic acid. All of these results indicate that OalS6 is a novel oligoalginate lyase that is structurally and functionally different from other known oligoalginate lyases. This finding provides new insights into the development of biofuel processing biotechnologies from seaweed.

  15. Organic Solid-State Tri-Wavelength Lasing from Holographic Polymer-Dispersed Liquid Crystal and a Distributed Feedback Laser with a Doped Laser Dye and a Semiconducting Polymer Film.

    Science.gov (United States)

    Liu, Minghuan; Liu, Yonggang; Peng, Zenghui; Wang, Shaoxin; Wang, Qidong; Mu, Quanquan; Cao, Zhaoliang; Xuan, Li

    2017-05-07

    Organic solid-state tri-wavelength lasing was demonstrated from dye-doped holographic polymer-dispersed liquid crystal (HPDLC) distributed feedback (DFB) laser with semiconducting polymer poly[-methoxy-5-(2'-ethyl-hexyloxy)-1,4-phenylene-vinylene] (MEH-PPV) and laser dye [4-(dicyanomethylene)-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran] (DCM) by a one-step holography technique, which centered at 605.5 nm, 611.9 nm, and 671.1 nm. The temperature-dependence tuning range for the tri-wavelength dye-doped HPDLC DFB laser was as high as 8 nm. The lasing emission from the 9th order HPDLC DFB laser with MEH-PPV as active medium was also investigated, which showed excellent s-polarization characterization. The diffraction order is 9th and 8th for the dual-wavelength lasing with DCM as the active medium. The results of this work provide a method for constructing the compact and cost-effective all solid-state smart laser systems, which may find application in scientific and applied research where multi-wavelength radiation is required.

  16. Bioactive Compound Evaluation of Ethanol Extract from Geodorum densiflorum (Lam. Schltr. by GC-MS analysis

    Directory of Open Access Journals (Sweden)

    Keerthiga Manohar

    2015-06-01

    Full Text Available The phytochemical constituents are responsible for medicinal value of the plant species. The present investigation was carried out to analyze the bioactive components from the whole plant of Geodorum densiflorum (Lam. Schltr using GC-MS technique. The chemical compositions of the ethanolic extract of G. densiflorum were investigated using Perkin - Elmer Gas Chromatography – Mass Spectrometry and about twenty one bioactive phytochemical compounds were identified. The prevailing compounds where Hexadecanoic acid, Ethyl ester (38.884 %, Ionone (7.125 %, 3-Deoxy-d-mannoic lactone (7.4441 %, 2,3-Butanediol (4.725 % and 2-Piperidinone, N-[4-bromo-n-butyl]- (4.004 %, (E-9-Octadeconoic acid ethyl ester (3.891 %, 1H-Pyrrole-2-Carbonitrile (3.778 %, Pyridinium, 1-amino-, chloride (3.305 %, 4H- Pyran-4-one, 3,5-dihydroxy-2-methyl- (3.274 and having various biological activities. This was the first report on the identification of bioactive compounds from ethanol extract of G. densiflorum.

  17. Characterisation of the flavour profile from Graciano Vitis vinifera wine variety by a novel dual stir bar sorptive extraction methodology coupled to thermal desorption and gas chromatography-mass spectrometry.

    Science.gov (United States)

    Arbulu, Maria; Sampedro, M Carmen; Sanchez-Ortega, Alicia; Gómez-Caballero, Alberto; Unceta, Nora; Goicolea, M Aranzazu; Barrio, Ramón J

    2013-05-13

    The aim of this work was to develop a new analytical technique for the study of the organoleptic compounds (flavour profile) of the Graciano Vitis vinifera wine variety. The cv. Graciano is a singular variety of red grapes with its origins in La Rioja and Navarra (northern Spain). This variety transfers an intense red colour, aroma and high acidity to musts and provides greater longevity and, consequently, a better capacity for ageing wine. A new dual-stir bar sorptive extraction approach coupled with thermal desorption (TD) and GC-MS has been used to extract the volatile and semivolatile compounds. In this extraction step, the optimal values for the experimental variables were obtained through the Response Surface Methodology (RSM). Full scan chromatogram data were evaluated with two deconvolution software tools, and the results were compared. The volatile and semivolatile components were identified with an MS match ≥80%. As a result, the flavour metabolome of the Graciano Vitis vinifera wine variety was obtained, and 205 metabolites were identified using different databases. These metabolites were grouped into esters, acids, alcohols, nitrogen compounds, furans, lactones, ketones, aldehydes, phenols, terpenes, norisoprenoids, sulphur compounds, acetals and pyrans. The majority of the metabolites observed had already been reported in the literature; however, this work also identified new, previously unreported metabolites in red wines, which may be characteristic of the Graciano variety. Copyright © 2013 Elsevier B.V. All rights reserved.

  18. A novel melatonin agonist Neu-P11 facilitates memory performance and improves cognitive impairment in a rat model of Alzheimer' disease.

    Science.gov (United States)

    He, Pingping; Ouyang, Xinping; Zhou, Shouhong; Yin, Weidong; Tang, Chaoke; Laudon, Moshe; Tian, Shaowen

    2013-06-01

    Previous studies have shown that melatonin is implicated in modulating learning and memory processing. Melatonin also exerts neuroprotective activities against Aβ-induced injury in vitro and in vivo. Neu-P11 (piromelatine, N-(2-(5-methoxy-1H-indol-3-yl)ethyl)-4-oxo-4H-pyran-2-carboxamide) is a novel melatonin (MT1/MT2) receptor agonist and a serotonin 5-HT1A/1D receptor agonist recently developed for the treatment of insomnia. In the present study we firstly investigated whether Neu-P11 and melatonin enhance memory performance in the novel object recognition (NOR) task in rats, and then assessed whether Neu-P11 and melatonin improve neuronal and cognitive impairment in a rat model of Alzheimer' disease (AD) induced by intrahippocampal Aβ(1-42) injection. The results showed that a single morning or afternoon administration of Neu-P11 enhanced object recognition memory measured at 4 or 24h after training. Melatonin was effective in the memory facilitating effects only when administered in the afternoon. Further results showed that intrahippocampal Aβ(1-42) injection resulted in hippocampal cellular loss, as well as decreased learning ability and memory in the Y maze and NOR tasks in rats. Neu-P11 but not melatonin attenuated cellular loss and cognitive impairment in the rat AD model. The current data suggest that Neu-P11 may serve as a novel agent for the treatment of AD.

  19. Di-(2-ethylhexylphthalate and Pyranon Derivated from Endophytic fungi Penicillium sp the Leave of Kunyit Putih (Curcuma zedoaria

    Directory of Open Access Journals (Sweden)

    Muharni Muharni

    2014-10-01

    Full Text Available Two compounds from cultivation of the endophytic fungi Penicillium sp of leaves of kunyit putih (Curcuma zedoaria have been isolated. The endophytic fungus was cultivated on 5 L of Potatos Dextrose Broth (PDB medium at room temperature (no shaking for 3 weeks. The cultures were extracted with ethyl acetate to afford 3.0 g of residue after removal of the solvent under reduced pressure. The extract was separated and purified by silica gel column chromatography (CC and afforded two pure compounds as colorless oily liquid (compound 1 and yellow crystal (compound 2. The structure of these compounds were characterized by detailed UV, IR, and NMR spectroscopic analysis and compound 1 as well as comparison with the reported data. Base on spectra analysis the compound 1 was determined as Di-(2-ethylhexylphthalate and compound 2 as 5-(4’-ethoxy-2’-hydroxy-5’-methyl-2’,3’-dihydrofuran-3’-il (hydroxy methyl-4-isopropyl-3-methyl-2-pyran-2-on. Compound 1 is not new compound, but it is new for endophytic fungus from C. zeodoria and compound 2 is new compound.

  20. Inhibition of auxin transport and auxin signaling and treatment with far red light induces root coiling in the phospholipase-A mutant ppla-I-1. Significance for surface penetration?

    Science.gov (United States)

    Perrineau, F; Wimalasekera, R; Effendi, Y; Scherer, G F E

    2016-06-01

    When grown on a non-penetretable at a surface angle of 45°, Arabidopsis roots form wave-like structures and, in wild type rarely, but in certain mutants the tip root even may form circles. These circles are called coils. The formation of coils depends on the complex interaction of circumnutation, gravitropism and negative thigmotropism where - at least - gravitropism is intimately linked to auxin transport and signaling. The knockout mutant of patatin-related phospholipase-AI-1 (pplaI-1) is an auxin-signaling mutant which forms moderately increased numbers of coils on tilted agar plates. We tested the effects of the auxin efflux transport inhibitor NPA (1-naphthylphtalamic acid) and of the influx transport inhibitor 1-NOA (1-naphthoxyacetic acid) which both further increased root coil formation. The pPLAI-1 inhibitors HELSS (haloenol lactone suicide substrate=E-6-(bromomethylene)tetrahydro-3-(1-naphthalenyl)-2H-pyran-2-one) and ETYA (eicosatetraynoic acid) which are auxin signaling inhibitors also increased coil formation. In addition, far red light treatment increased coil formation. The results point out that a disturbance of auxin transport and signaling is one potential cause for root coils. As we show that the mutant pplaI-1 penetrates horizontal agar plates better than wild type plants root movements may help penetrating the soil.

  1. Structurally diverse secondary metabolites from a deep-sea-derived fungus Penicillium chrysogenum SCSIO 41001 and their biological evaluation.

    Science.gov (United States)

    Chen, Shengtian; Wang, Junfeng; Wang, Zhen; Lin, Xiuping; Zhao, Bingxin; Kaliaperumal, Kumaravel; Liao, Xiaojian; Tu, Zhengchao; Li, Jianlin; Xu, Shihai; Liu, Yonghong

    2017-03-01

    Five new compounds, including a cytotoxic dimeric isocoumarin, bipenicilisorin (1), a merosesquiterpenoid, yaminterritrem C (2), a citrinin dimer, penicitrinone F (3), a alkaloid, terremide D (4), and a δ-valerolacton, (E)-4-(propen-1-yl)-5,6-dihydro-2H-pyran-2-one (5), along with ten known compounds (6-15) were isolated from a deep-sea-derived fungus Penicillium chrysogenum SCSIO 41001. Their structures and absolute configurations were elucidated by NMR spectra, MS, CD, optical rotation, X-ray crystallography, and compared with literature data. Biological evaluation results revealed that 1 exhibited significant cytotoxic activities against K562, A549, and Huh-7 cell lines with IC50 values of 6.78, 6.94, and 2.59μM, respectively. Compound 3 exhibited moderate inhibitory activity against EV71 with IC50 value of 14.50μM. In addition, 13 and 14 showed specific COX-2 inhibitory activities with IC50 values of 1.09 and 1.97μM, respectively.

  2. Useful dual Diels-Alder behavior of 2-azetidinone-tethered aryl imines as azadienophiles or azadienes: a beta-lactam-based stereocontrolled access to optically pure highly functionalized indolizidine systems.

    Science.gov (United States)

    Alcaide, Benito; Almendros, Pedro; Alonso, Jose M; Aly, Moustafa F

    2003-07-21

    Imines derived from 4-oxoazetidine-2-carbaldehydes have been found to be versatile Diels-Alder reagents in that they exhibit two reactivity patterns. 2-Azetidinone-tethered imines undergo diastereoselective reaction with Danishefsky's diene in the presence of different Lewis acids. The effect of the amount of catalyst on the conversion rate as well as on the product ratio has been studied. Under standard reaction conditions, indium(III) chloride and zinc(II) iodide provided the best yields, and indium(III) triflate the highest diastereoselectivity in the Lewis acid promoted aza-Diels-Alder cycloaddition. Treatment of the aforementioned imines with cyclopentadiene, 2,3-dimethyl-1,3-butadiene or 3,4-dihydro-2 H-pyran led to cycloadducts arising from inverse electron-demand condensation involving the beta-lactam-tethered aryl imine as the heterodiene component. In addition, the first methodology for preparing indolizidines from beta-lactams has been developed. This process involves amide bond cleavage of the beta-lactam ring in the aza-Diels-Alder cycloadducts with concomitant cyclization. Full chirality transfer occurs when the reaction is performed with an enantiomerically pure substrate.

  3. Single step synthesis of strigolactone analogues from cyclic keto enols, germination stimulants for seeds of parasitic weeds.

    Science.gov (United States)

    Mwakaboko, Alinanuswe S; Zwanenburg, Binne

    2011-08-15

    The single step synthesis of a newly designed series of strigolactones (SLs) from cyclic keto enols is described. The germinating activity of these SL analogues towards seeds of the parasitic weeds Striga and Orobanche spp. is reported. The first of these SL analogues are derived from the hydroxyl γ-pyrones kojic acid and maltol, the second type from hydroxyl α-pyrones, namely, 4-hydroxy-6-methyl-2H-pyran-2-one and 4-hydroxy-coumarin and the third type from 1,3-diketones, namely, 1,3-cyclohexane-dione (dimedone) and tricyclic 1,3-dione. All keto enols are coupled in a single step with the appropriate D-ring precursor in the presence of a base to give the desired SL analogues. All SL analogues are acceptably biologically active in inducing the germination of seeds of Striga hermonthica and Orobanchecernua. Most interesting are the analogues derived from 4-hydroxy coumarin and dimedone, as they have a remarkably high biological activity towards the seeds of parasitic weeds at relatively low concentrations, comparable with that of the general standard stimulant GR24. Copyright © 2011 Elsevier Ltd. All rights reserved.

  4. Pyridine analogues of spirocyclic σ₁ receptor ligands.

    Science.gov (United States)

    Miyata, Kengo; Möller, Guido; Schepmann, Dirk; Wünsch, Bernhard

    2014-08-01

    Spirocyclic benzopyrans 2 interact with high affinity and selectivity with σ₁ receptors. Bioisosteric replacement of the benzene ring of the benzopyran substructure with the electron rich thiophene ring (3) led to increased σ₁ affinity. Herein the synthesis and pharmacological evaluation of electron deficient pyridine bioisosteres 4 are reported. Homologation of the aldehyde 6 to afford the pyridylacetaldehyde derivative 8 was performed by a Wittig reaction. Bromine lithium exchange of the bromopyridine 8, addition to 1-benzylpiperidin-4-one and cyclization led to the spirocyclic pyrranopyridine 10. Hydrogenolytic removal of the N-benzyl moiety of 10 provided the secondary amine 11, which allowed the introduction of various N-substituents (12a-d). Cyclization of the hydroxy acetal 9 with HCl led to various modifications of the substituent in 3'-position. Generally the σ₁ affinity of the pyridine derivatives is reduced compared with those of the benzene and thiophene derivatives 2 and 3. However, the relationships between the structure and the σ₁ affinity follow the same rules as for the benzene and thiophene derivatives. The most promising σ₁ ligand within this class of compounds is the pyranopyridine 15 with a double bond in the pyran ring revealing a Ki-value of 4.6 nM and a very high selectivity (>217-fold) over the σ₂ subtype.

  5. Identification of prenylated pterocarpans and other isoflavonoids in Rhizopus spp. elicited soya bean seedlings by electrospray ionisation mass spectrometry.

    Science.gov (United States)

    Simons, Rudy; Vincken, Jean-Paul; Bohin, Maxime C; Kuijpers, Tomas F M; Verbruggen, Marian A; Gruppen, Harry

    2011-01-15

    Phytoalexins from soya are mainly characterised as prenylated pterocarpans, the glyceollins. Extracts of non-soaked and soaked soya beans, as well as that of soya seedlings, grown in the presence of Rhizopus microsporus var. oryzae, were screened for the presence of prenylated flavonoids with a liquid chromatography/mass spectrometry (LC/MS)-based screening method. The glyceollins I-III and glyceollidins I-II, belonging to the isoflavonoid subclass of the pterocarpans, were tentatively assigned. The formation of these prenylated pterocarpans was accompanied by that of other prenylated isoflavonoids of the subclasses of the isoflavones and the coumestans. It was estimated that approx. 40% of the total isoflavonoid content in Rhizopus-challenged soya bean seedlings were prenylated pterocarpans, whereas 7% comprised prenylated isoflavones and prenylated coumestans. The site of prenylation (A-ring or B-ring) of the prenylated isoflavones was tentatively annotated using positive-ion mode MS by comparing the (1,3) A(+) retro-Diels-Alder (RDA) fragments of prenylated and non-prenylated isoflavones. Furthermore, the fragmentation pathways of the five pterocarpans in negative-ion (NI) mode were proposed, which involved the cleavage of the C-ring and/or D-ring. The absence of the ring-closed prenyl (pyran or furan) gave exclusively -H(2) O(x,y) RDA fragments, whereas its presence gave predominantly the common RDA fragments. Copyright © 2010 John Wiley & Sons, Ltd.

  6. Primary study on the Characterization of polysaccharides from Anoectochilus Roxburghii%金线莲多糖结构的初步分析

    Institute of Scientific and Technical Information of China (English)

    杨振国; 张晓辉; 余杰

    2015-01-01

    目的:初步分析活性药物金线莲多糖(PSA)化学结构特征。方法采用红外光谱分析法分析多糖官能团和糖苷键构型,气相色谱法测定多糖的单糖组成。结果 PSA由葡萄糖、阿拉伯糖、木糖、半乳糖、鼠李糖和甘露糖6种单糖组成。其中半乳糖和葡萄糖的比例占75%以上。多糖中单糖含有α-和β-吡喃环。结论 PSA复杂的结构构象是其具有多种药效活性的原因之一。%Objective Study on the structure feature of polysaccharides from Anoectochilus roxburghi (PSA).Methods The characterization and component of PSA were analyzed by infrared spectrum and gas chromato- graphy.Results PSA is composed of glucose, Arabia sugar, xylose, galactose, rhamnose and mannose composed of 6 monosaccharides. The galactose and glucose accounted for more than 75%. PSA possess alpha and beta pyran ring characterization. Conclusion Complex conformation of PSA maybe is the reason of its various pharmacod-ynamic activity.

  7. 黑壳楠叶片精油挥发性成分的GC/MS 鉴定与应用分析%GC/MS Analysis of Volatile Substances in Essential Oil of Lindera megaphylla Blade and Its Application

    Institute of Scientific and Technical Information of China (English)

    卞京军; 程密密; 罗思源; 陈思伶; 刘世尧; 白志川

    2014-01-01

    The essential oil was extracted from the leaves of the Lauraceae plant L indera megaphylla with steam distillation, and the volatile substances in it were analyzed and identified with GC-MS. A total of 87 volatile aromatic substances were separated and identified, accounting for 95.6% of the total essential oil, hydrocarbons (37% ) and alcohols (34.74% ) being the principal components. The first ten kinds of volatile components were Phytol (14.3% ), n-Hexadecanoic acid (6.09% ), D-Limonene (4.67% ), 2H-Pyran, 2-(2-heptadecynyloxy)tetrahydro-(4.65% ), Copaene (4.3% ), alpha-Cadinol (4.23% ), Caryophyllene ox-ide (4.11% ), 1, 6, 10-Dodecatrien-3-ol, 3, 7, 11-trimethyl-(3.32% ), Cyclohexane, 1-ethenyl-1-methyl-2, 4-bis (1-methyle thenyl)-, [1S-(1.alpha., 2. beta., 4. beta. )]-(3.24% ), Bicyclo[2.2.1]heptan-2-ol, 1, 7, 7-trimethyl-, acetate, (1S-endo)-(2.62% ), of which Phytol, n-Hexadecanoic acid and D-Limonene might be of considerable value of development and utilization.%采用水蒸气蒸馏法对樟科植物黑壳楠叶片进行精油提取,并对其挥发性成分进行气相色谱质谱联用仪(GC/MS)分离鉴定与应用分析.结果表明:在重庆黑壳楠叶片中分离鉴定出挥发性成分87种,占精油总量的95.6%,以烃类(37%)、醇类(34.74%)化合物为主.前10种挥发性成分分别为:植物醇(14.3%)、棕榈酸(6.09%)、右旋柠檬烯(4.67%)、2H-Pyran ,2-(2-heptadecynyloxy)tetrahydro-(4.65%)、古巴烯(4.3%)、荜茄醇(4.23%)、氧化石竹烯(4.11%)、反式橙花叔醇(3.32%)、β榄香烯(3.24%)、乙酸龙脑酯(2.62%),其中植物醇、棕榈酸、右旋柠檬烯等有较大开发利用价值.

  8. Comprehensive two-dimensional gas chromatography - time-of-flight mass spectrometry and simultaneous electron capture detection/nitrogen phosphorous detection for incense analysis

    Science.gov (United States)

    Tran, Tin C.; Marriott, Philip J.

    This study reports comprehensive two-dimensional gas chromatography hyphenated to time-of-flight mass spectrometry detection (GC × GC/TOFMS) for characterisation and identification of components generated by four different types of powdered incense headspace (H/S) and incense smoke. GC × GC/TOFMS allowed simultaneous separation and identification of compounds emitted into the atmosphere as a result of combustion of incense powder. The smoke stream comprised compounds originating from the incense powder, and combustion products such as saturated and unsaturated hydrocarbons, essential oil type compounds, nitromusks, fatty acid methyl esters (FAMEs), polycyclic aromatic hydrocarbons (PAHs, which possibly include oxygenated and nitrated PAH), N-heterocyclics, pyrans and furans, which were detected and tentatively identified by GC × GC/TOFMS. GC × GC-electron capture detector/nitrogen phosphorous detector (ECD/NPD) potentially offers the prospect of providing selective chemical compositional information of incense powder and smoke, such as nitrogen-containing (N-containing) and halogenated compounds. Results of GC×GC-ECD/NPD showed that both incense powder and smoke generated emission of N-containing and halogenated compounds. A significant number of halogenated and N-containing compounds were emitted during the incomplete combustion of incense. However, one further objective of this paper is to demonstrate the capacity of comprehensive two-dimensional gas chromatography coupled to specific and/or selective detectors such as those used in this study (GC × GC-ECD/NPD) for the detection of particular classes of compounds such as N-containing and halogenated compounds at trace level concentrations in complex smoke samples.

  9. Combined optical gain and degradation measurements in DCM2 doped Tris-(8-hydroxyquinoline)aluminum thin-films

    Science.gov (United States)

    Čehovski, Marko; Döring, Sebastian; Rabe, Torsten; Caspary, Reinhard; Kowalsky, Wolfgang

    2016-04-01

    Organic laser sources offer the opportunity to integrate flexible and widely tunable lasers in polymer waveguide circuits, e.g. for Lab-on-Foil applications. Therefore, it is necessary to understand gain and degradation processes for long-term operation. In this paper we address the challenge of life-time (degradation) measurements of photoluminescence (PL) and optical gain in thin-film lasers. The well known guest-host system of aluminum-chelate Alq3 (Tris-(8-hydroxyquinoline)aluminum) as host material and the laser dye DCM2 (4-(Dicyanomethylene)-2- methyl-6-julolidyl-9-enyl-4H-pyran) as guest material is employed as laser active material. Sample layers have been built up by co-evaporation in an ultrahigh (UHV) vacuum chamber. 200nm thick films of Alq3:DCM2 with different doping concentrations have been processed onto glass and thermally oxidized silicon substrates. The gain measurements have been performed by the variable stripe length (VSL) method. This measurement technique allows to determine the thin-film waveguide gain and loss, respectively. For the measurements the samples were excited with UV irradiation (ƛ = 355nm) under nitrogen atmosphere by a passively Q-switched laser source. PL degradation measurements with regard to the optical gain have been done at laser threshold (approximately 3 μJ/cm2), five times above laser threshold and 10 times above laser threshold. A t50-PL lifetime of > 107 pulses could be measured at a maximum excitation energy density of 32 μJ/cm2. This allows for a detailed analysis of the gain degradation mechanism and therefore of the stimulated cross section. Depending on the DCM2 doping concentration C the stimulated cross section was reduced by 35 %. Nevertheless, the results emphasizes the necessity of the investigation of degradation processes in organic laser sources for long-term applications.

  10. Density functional theory and RRKM calculations of decompositions of the metastable E-2,4-pentadienal molecular ions.

    Science.gov (United States)

    Solano Espinoza, Eduardo A; Vallejo Narváez, Wilmer E

    2010-07-01

    The potential energy profiles for the fragmentations that lead to [C(5)H(5)O](+) and [C(4)H(6)](+*) ions from the molecular ions [C(5)H(6)O](+*) of E-2,4-pentadienal were obtained from calculations at the UB3LYP/6-311G + + (3df,3pd)//UB3LYP/6-31G(d,p) level of theory. Kinetic barriers and harmonic frequencies obtained by the density functional method were then employed in Rice-Ramsperger-Kassel-Marcus calculations of individual rate coefficients for a large number of reaction steps. The pre-equilibrium and rate-controlling step approximations were applied to different regions of the complex potential energy surface, allowing the overall rate of decomposition to be calculated and discriminated between three rival pathways: C-H bond cleavage, decarbonylation and cyclization. These processes should have to compete for an equilibrated mixture of four conformers of the E-2,4-pentadienal ions. The direct dissociation, however, can only become important in the high-energy regime. In contrast, loss of CO and cyclization are observable processes in the metastable kinetic window. The former involves a slow 1,2-hydrogen shift from the carbonyl group that is immediately followed by the formation of an ion-neutral complex which, in turn, decomposes rapidly to the s-trans-1,3-butadiene ion [C(4)H(6)](+*). The predominating metastable channel is the second one, that is, a multi-step ring closure which starts with a rate-limiting cis-trans isomerization. This process yields a mixture of interconverting pyran ions that dissociates to the pyrylium ions [C(5)H(5)O](+). These results can be used to rationalize the CID mass spectrum of E-2,4-pentadienal in a low-energy regime.

  11. Stereoselective synthesis of 2,2-bis(C-branched-chain) glucopyranosid-3-ulose via autoxidation reaction

    Institute of Scientific and Technical Information of China (English)

    LIU Hong-Min; ZHANG Fuyi; TAO Jing-Chao

    2004-01-01

    Many different approaches for synthesis of branched chain sugars have beenestablished,1 because they are very useful intermediates for synthesis of other non-sugar chiralmolecules, and usually occur in nature. Branched chain glycosidulose can be used for construction offive- and six-membered carbocyclic rings to which two chiral carbons of sugar are incorporated byintramolecular aldol condensation and Robinson annulation,2 Therefore they are useful in thesynthesis of natural products which consist of annulated carbohydrates or where a highlyfunctionalised enantiomerically pure cyclopentane or cyclohexane is required. Also, this type ofbranched chain sugar can be considered as the synthons of monoterpenoid natural products of theiridoid class which have the cyclopentan-(c)-pyran structure. In view of the importance of branchedchain glycosiduloses, it is desirable to have a general, convenient methodology to their synthesis.However, none of the literature methods was reported on their synthesis by a nuclephilic addition toa partially protected glycosidulose, due to the fact that these glycosiduloses are very difficult tosynthesize selectively and unstable;3 and what is more, one-step synthesis branched chainglycosidulose using this method is almost impossible.In this paper, we report on a general, convenient method for stereoselective syntheses of2,2-bis(C-branched-chain)glucopyranosid-3-uloses by the new reaction of 1 with various activemethylene compounds. The generality of this method was examined in detail. The optimumtemperature was 18-25℃. The solvent DMF was better than the others. In all cases he yields werehigher than 60%.All the 2,2-bis(C-branched-chain)glucopyranosid-3-uloses were characterized by X-raycrystallographic analyses. In addition, the important iintermediate in this reaction was isolated,which is the product of autoxidation of 1 at C-3 position. Thus the reaction mechanism for thesynthesis of 2,2-bis(C-branched-chain) glucopyranosid-3-uloses

  12. HARNESSING THE CHEMISTRY OF CO2

    Energy Technology Data Exchange (ETDEWEB)

    Louie, Janis

    2010-05-11

    Our research program is broadly focused on activating CO{sub 2} through the use of organic and organometallic based catalysts. Some of our methods have centered on annulation reactions of unsaturated hydrocarbons (and carbonyl substrates) to provide a diverse array of carbocycles and heterocycles. We use a combination of catalyst discovery and optimization in conjunction with classical physical organic chemistry to elucidate the key mechanistic features of the cycloaddition reactions such that the next big advances in catalyst development can be made. Key to all of our cycloaddition reactions is the use of a sterically hindered, electron donating N heterocyclic carbene (NHC) ligand, namely IPr (or SIPr), in conjunction with a low valent nickel pre-catalyst. The efficacy of this ligand is two-fold: (1) the high {delta}-donating ability of the NHC increases the nucleophilicity of the metal center which thereby facilitates interaction with the electrophilic carbonyl and (2) the steric hindrance prevents an otherwise competitive side reaction involving only the alkyne substrate. Such a system has allowed for the facile cycloaddition to prepare highly functionalized pyrones, pyridones, pyrans, as well as novel carbocycles. Importantly, all reactions proceed under extremely mild conditions (room temperature, atmospheric pressures, and short reaction times), require only catalytic amounts of Ni/NHC and readily available starting materials, and afford annulated products in excellent yields. Our current focus revolves around understanding the fundamental processes that govern these cycloadditions such that the next big advance in the cyclization chemistry of CO{sub 2} can be made. Concurrent to our annulation chemistry is our investigation of the potential for imidazolylidenes to function as thermally-actuated CO{sub 2} sequestering and delivery agents.

  13. DCJTB掺杂浓度对OLED器件性能的影响%Effects of DCJCB Doping Concentration on Performances of Organic Light-Emitting Diodes

    Institute of Scientific and Technical Information of China (English)

    刘丁菡; 张方辉; 牟强

    2010-01-01

    A highly efficient white organic light-emitting device could be achieved by changing doping concentration in the emissive layer of the device containing 9,10-di-(2-naph-thyl)anthracene ( AND ),2,5,8,11-tetra-butyl-perylene(TBPe) and 4- ( Dicyanomethylene)-2-t-butyl6-(1,1,7,7-tetramethylj-ulolidyl-9-enyl)-4H-pyran(DCJT B).By examining the device characteristics of uniformly doped devices with varying dopant concentration,it is found that the device with the doping concentration(mass fraction) of 1% DCJTB gains the maximum current(ηL) and power(ηP) efficiencies,which are 6.6 cd/A and 3.21 lm/W at luminance of 10 520 cd/m2 with CIE coordinates of (0.318 6,0.352 0).The different color of devices can be obtained by changing doping concentration of DCJTB.%通过在发光层ADN:TBPe:DCJTB中改变DCJTB的掺杂浓度,得到了一种高效的白光OLED器件.考察了同一掺杂浓度TBPe下不同浓度的DCJTB的器件性能,发现当DCJTB掺杂浓度为1%(质量分数)时,器件获得最大电流效率6.6 cd/A和最大功率效率3.21 lm/W,此时亮度为10 520 cd/m2,对应的CIE坐标为(0.318 6,0.352 0).通过改变DCJTB浓度,能够获得不同的器件颜色.

  14. Synthesis, characterization, ab initio calculations, thermal behaviour and thermodynamics of some oxovanadium(IV) complexes involving O,O- and ,-donor moieties

    Indian Academy of Sciences (India)

    Mozaffar Asadi; Mohammad Hadi Ghatee; Susan Torabi; Khosro Mohammadi; Fatemeh Moosavi

    2010-07-01

    Some oxovanadium(IV) complexes, namely bis(1,1,1-trifluro-2,4-pentanedionato-,') oxovanadium (IV), [VO(tfac)2(H2O)], bis(1-phenyl-2,4-pentanedionato-,')oxovanadium(IV), [VO(phac)2(H2O)], bis(1,3-diphenyl-2,4-pentanedionato-,')oxovanadium(IV), [VO(dphac)2 (H2O)], of the type [VO(O4)] and bis(pyrolidineaniline)oxovanadium(IV), [VO(pyran)2(H2O)], bis(-hydroxypyrolidineaniline) oxovanadium(IV), [VO(-hydroxypyran)2(H2O)], bis(-methoxypyrolidineaniline)oxovanadium(IV), [VO(-MeOpyran)2 (H2O)], bis(-chloropyrolidineaniline)oxovanadium(IV), [VO(-chloropyran)2(H2O)], bis(-bromopyrolidineaniline)oxovanadium(IV), [VO(-bromopyran)2(H2O)], bis(-cyano pyrolidineaniline)oxovanadium(IV), [VO(-cyanopyran)2(H2O)], and bis(pyrolidinebenzylamine)oxovanadium(IV), [VO(pyrbz)2(H2O)], of the type [VO(N4)] were synthesized and characterized by IR, UV-Vis, mass spectrometry, elemental analysis, magnetic moment and thermogravimetry in order to evaluate their thermal stability and thermal decomposition pathways. The number of steps and, in particular, the starting temperature of decomposition of these complexes depends on the equatorial ligand. Also, formation constants of the complexes have been determined by UV-Vis absorption spectroscopy through titration of the ligands with the metal ions at constant ionic strength (0.1 M NaClO4) and at 25°C. According to the thermodynamic studies, as the steric character of the ligand increases, the complexation tendency to VO(IV) center decreases. Also, the ab initio calculations were carried out to determine the structural and the geometrical properties of the complexes.

  15. 5‑bromo‑3‑(3‑hydroxyprop‑1‑ynyl)‑2H‑pyran‑2‑one induces apoptosis in T24 human bladder cancer cells through mitochondria-dependent signaling pathways.

    Science.gov (United States)

    Yu, Guo-Qiang; Dou, Zhong-Ling; Jia, Zhao-Hui

    2017-01-01

    The present study was performed to investigate the effect of 5-bromo-3-(3-hydroxyprop-1-ynyl)-2H-pyran-2-one (BHP) on the induction of apoptosis and cell cycle arrest in T24 human bladder carcinoma cells. An MTT assay was used to investigate the inhibition of cell proliferation. Flow cytometry was used to observe alterations in the cell cycle, generation of reactive oxygen species (ROS), alterations in mitochondrial membrane potential (MMP) and induction of apoptosis in the T24 cells following BHP treatment. Western blot analysis was performed for the determination of expression levels of apoptotic proteins, and 4,6‑diamidino‑2‑phenylindole dihydrochloride staining was used to observe apoptosis and DNA damage. The results demonstrated that treatment of the bladder cancer cells with BHP enhanced the activation of caspases and increased the production of ROS. It also caused damage to DNA, reduced MMP, and increased the secretion of endonuclease G and apoptosis‑inducing factor from the mitochondria. The expression levels of cyclin E and cell division cycle 25C were reduced, whereas the expression levels of p21 and phosphorylated p53 were increased in the BHP‑treated cells. In addition, treatment with BHP caused cell cycle arrest at the G0/G1 phase, increased the expression levels of B cell lymphoma‑2 (Bcl‑2)‑associated X protein and poly(ADP‑ribose) polymerase, decreased the expression of Bcl‑2 and ultimately induced apoptosis of the T24 cells. Thus, BHP inhibited the proliferation of bladder cancer cells by inducing cell apoptosis through the mitochondrial pathway.

  16. Correlating the motion of electrons and nuclei with two-dimensional electronic-vibrational spectroscopy.

    Science.gov (United States)

    Oliver, Thomas A A; Lewis, Nicholas H C; Fleming, Graham R

    2014-07-15

    Multidimensional nonlinear spectroscopy, in the electronic and vibrational regimes, has reached maturity. To date, no experimental technique has combined the advantages of 2D electronic spectroscopy and 2D infrared spectroscopy, monitoring the evolution of the electronic and nuclear degrees of freedom simultaneously. The interplay and coupling between the electronic state and vibrational manifold is fundamental to understanding ensuing nonradiative pathways, especially those that involve conical intersections. We have developed a new experimental technique that is capable of correlating the electronic and vibrational degrees of freedom: 2D electronic-vibrational spectroscopy (2D-EV). We apply this new technique to the study of the 4-(di-cyanomethylene)-2-methyl-6-p-(dimethylamino)styryl-4H-pyran (DCM) laser dye in deuterated dimethyl sulfoxide and its excited state relaxation pathways. From 2D-EV spectra, we elucidate a ballistic mechanism on the excited state potential energy surface whereby molecules are almost instantaneously projected uphill in energy toward a transition state between locally excited and charge-transfer states, as evidenced by a rapid blue shift on the electronic axis of our 2D-EV spectra. The change in minimum energy structure in this excited state nonradiative crossing is evident as the central frequency of a specific vibrational mode changes on a many-picoseconds timescale. The underlying electronic dynamics, which occur on the hundreds of femtoseconds timescale, drive the far slower ensuing nuclear motions on the excited state potential surface, and serve as a excellent illustration for the unprecedented detail that 2D-EV will afford to photochemical reaction dynamics.

  17. Synthesis and antitumor activity of [1,2-bis(4-fluorophenyl)ethylenediamine][dicarboxylato]platinum(II) complexes.

    Science.gov (United States)

    Gust, R; Krauser, R; Schmid, B; Schönenberger, H

    1998-01-01

    The synthesis of the diastereomeric [1,2-bis(4-fluorophenyl)-ethylenediamine][dicarboxylato]platinum(I I) complexes, rac- and meso-4F-Pt(X) [X: oxalato (Ox), malonato (Mal), hydroxymalonato (OHMal), phenylmalonato (PhMal), tetrahydro-4H-pyran-4,4-dicarboxylato (Thpdc)], the evaluation of their structure, water solubility, resistance against attack by nucleophiles, and growth inhibiting properties on the human MCF-7 breast cancer cell line are described [parent compounds: rac-4F-Pt(CBDC) and meso-4F-Pt(CBDC); reference complexes: carboplatin, cisplatin, rac- and meso-4F-PtCl2]. The most active 4F-Pt(X) complexes, rac-4F-Pt(Mal), rac-4F-Pt(OHMal) and rac-4F-Pt(Thpdc), equal the parent compound rac-4F-Pt(CBDC) as well as cisplatin and surpass carboplatin in their effect on the MCF-7 breast cancer cell line. Their water solubility, which is of importance for an application in the cancer chemotherapy, is higher than that of rac-4F-Pt(CBDC), especially in the case of rac-4F-Pt(OHMal) and rac-4F-Pt(Thpdc). In comparison to the dichloroplatinum(II) analogue (4F-PtCl2) the stability of the three compounds in the presence of the strong nucleophile iodide is markedly enhanced, which means a reduction of the protein bound drug fraction in the blood and tissue compartments accompanied by an increase of the active, free drug level. The found physiochemical properties of these compounds meet the requirements for the transferability of their promising breast cancer inhibiting effects detected in cell culture experiments to in vivo conditions.

  18. Exploring the Saccharomyces cerevisiae Volatile Metabolome: Indigenous versus Commercial Strains.

    Directory of Open Access Journals (Sweden)

    Zélia Alves

    Full Text Available Winemaking is a highly industrialized process and a number of commercial Saccharomyces cerevisiae strains are used around the world, neglecting the diversity of native yeast strains that are responsible for the production of wines peculiar flavours. The aim of this study was to in-depth establish the S. cerevisiae volatile metabolome and to assess inter-strains variability. To fulfill this objective, two indigenous strains (BT2652 and BT2453 isolated from spontaneous fermentation of grapes collected in Bairrada Appellation, Portugal and two commercial strains (CSc1 and CSc2 S. cerevisiae were analysed using a methodology based on advanced multidimensional gas chromatography (HS-SPME/GC×GC-ToFMS tandem with multivariate analysis. A total of 257 volatile metabolites were identified, distributed over the chemical families of acetals, acids, alcohols, aldehydes, ketones, terpenic compounds, esters, ethers, furan-type compounds, hydrocarbons, pyrans, pyrazines and S-compounds. Some of these families are related with metabolic pathways of amino acid, carbohydrate and fatty acid metabolism as well as mono and sesquiterpenic biosynthesis. Principal Component Analysis (PCA was used with a dataset comprising all variables (257 volatile components, and a distinction was observed between commercial and indigenous strains, which suggests inter-strains variability. In a second step, a subset containing esters and terpenic compounds (C10 and C15, metabolites of particular relevance to wine aroma, was also analysed using PCA. The terpenic and ester profiles express the strains variability and their potential contribution to the wine aromas, specially the BT2453, which produced the higher terpenic content. This research contributes to understand the metabolic diversity of indigenous wine microflora versus commercial strains and achieved knowledge that may be further exploited to produce wines with peculiar aroma properties.

  19. Thermochemical properties and contribution groups for ketene dimers and related structures from theoretical calculations.

    Science.gov (United States)

    Morales, Giovanni; Martínez, Ramiro

    2009-07-30

    This research's main goals were to analyze ketene dimers' relative stability and expand group additivity value (GAV) methodology for estimating the thermochemical properties of high-weight ketene polymers (up to tetramers). The CBS-Q multilevel procedure and statistical thermodynamics were used for calculating the thermochemical properties of 20 cyclic structures, such as diketenes, cyclobutane-1,3-diones, cyclobut-2-enones and pyran-4-ones, as well as 57 acyclic base compounds organized into five groups. According to theoretical heat of formation predictions, diketene was found to be thermodynamically favored over cyclobutane-1,3-dione and its enol-tautomeric form (3-hydroxycyclobut-2-enone). This result did not agree with old combustion experiments. 3-Hydroxycyclobut-2-enone was found to be the least stable dimer and its reported experimental detection in solution may have been due to solvent effects. Substituted diketenes had lower stability than substituted cyclobutane-1,3-diones with an increased number of methyl substituents, suggesting that cyclobutane-1,3-dione type dimers are the major products because of thermodynamic control of alkylketene dimerization. Missing GAVs for the ketene dimers and related structures were calculated through linear regression on the 57 acyclic base compounds. Corrections for non next neighbor interactions (such as gauche, eclipses, and internal hydrogen bond) were needed for obtaining a highly accurate and precise regression model. To the best of our knowledge, the hydrogen bond correction for GAV methodology is the first reported in the literature; this correction was correlated to MP2/6-31Gdagger and HF/6-31Gdagger derived geometries to facilitate its application. GAVs assessed by the linear regression model were able to reproduce acyclic compounds' theoretical thermochemical properties and experimental heat of formation for acetylacetone. Ring formation and substituent position corrections were calculated by consecutively

  20. Tailoring molecularly imprinted polymer beads for alternariol recognition and analysis by a screening with mycotoxin surrogates.

    Science.gov (United States)

    Abou-Hany, Rahma A G; Urraca, Javier L; Descalzo, Ana B; Gómez-Arribas, Lidia N; Moreno-Bondi, María C; Orellana, Guillermo

    2015-12-18

    Molecularly imprinted porous polymer microspheres have been prepared for selective binding of alternariol (AOH), a phenolic mycotoxin produced by Alternaria fungi. In order to lead the synthesis of recognition materials, four original AOH surrogates have been designed, prepared and characterized. They bear different number of phenol groups in various positions and different degree of O-methylation on the dibenzo[b,d]pyran-6-one skeleton. A comprehensive library of mixtures of basic, acidic or neutral monomers, with divinylbenzene or ethyleneglycol dimethacrylate as cross-linkers, were polymerized at a small scale in the presence of the four molecular mimics of the toxin molecule. This polymer screening has allowed selection of the optimal composition of the microbeads (N-(2-aminoethyl)methacrylamide, EAMA, and ethylene glycol dimethacrylate). The latter are able to bind AOH in water-acetonitrile (80:20, v/v) with an affinity constant of 109±10mM(-1) and a total number of binding sites of 35±2μmolg(-1), being alternariol monomethylether the only competitor species. Moreover, (1)H NMR titrations have unveiled a 1:2 surrogate-to-EAMA stoichiometry, the exact interaction sites and a binding constant of 1.5×10(4)M(-2). A molecularly imprinted solid phase extraction (MISPE) method has been optimized for selective isolation of the mycotoxin from aqueous samples upon a discriminating wash with 3mL of acetonitrile/water (20:80, v/v) followed by determination by HPLC with fluorescence detection. The method has been applied, in combination to ultrasound-assisted extraction, to the analysis of AOH in tomato samples fortified with the mycotoxin at five concentration levels (33-110μgkg(-1)), with recoveries in the range of 81-103% (RSD n=6). To the best of our knowledge, this is the first imprinted material capable of molecularly recognizing this widespread food contaminant.

  1. Cytochrome P450-mediated oxidative metabolism of abused synthetic cannabinoids found in K2/Spice: identification of novel cannabinoid receptor ligands.

    Science.gov (United States)

    Chimalakonda, Krishna C; Seely, Kathryn A; Bratton, Stacie M; Brents, Lisa K; Moran, Cindy L; Endres, Gregory W; James, Laura P; Hollenberg, Paul F; Prather, Paul L; Radominska-Pandya, Anna; Moran, Jeffery H

    2012-11-01

    Abuse of synthetic cannabinoids (SCs), such as [1-naphthalenyl-(1-pentyl-1H-indol-3-yl]-methanone (JWH-018) and [1-(5-fluoropentyl)-1H-indol-3-yl]-1-naphthalenyl-methanone (AM2201), is increasing at an alarming rate. Although very little is known about the metabolism and toxicology of these popular designer drugs, mass spectrometric analysis of human urine specimens after JWH-018 and AM2201 exposure identified monohydroxylated and carboxylated derivatives as major metabolites. The present study extends these initial findings by testing the hypothesis that JWH-018 and its fluorinated counterpart AM2201 are subject to cytochrome P450 (P450)-mediated oxidation, forming potent hydroxylated metabolites that retain significant affinity and activity at the cannabinoid 1 (CB(1)) receptor. Kinetic analysis using human liver microsomes and recombinant human protein identified CYP2C9 and CYP1A2 as major P450s involved in the oxidation of the JWH-018 and AM2201. In vitro metabolite formation mirrored human urinary metabolic profiles, and each of the primary enzymes exhibited high affinity (K(m) = 0.81-7.3 μM) and low to high reaction velocities (V(max) = 0.0053-2.7 nmol of product · min(-1) · nmol protein(-1)). The contribution of CYP2C19, 2D6, 2E1, and 3A4 in the hepatic metabolic clearance of these synthetic cannabinoids was minimal (f(m) = receptor, which was attenuated by the CB(1) receptor antagonist (6aR,10aR)-3-(1-methanesulfonylamino-4-hexyn-6-yl)-6a,7,10,10a-tetrahydro-6,6,9-trimethyl-6H-dibenzo[b,d]pyran (O-2050). Results from the present study provide critical, missing data related to potential toxicological properties of "K2" parent compounds and their human metabolites, including mechanism(s) of action at cannabinoid receptors.

  2. Extraction and identification of bioactive components in Sida cordata (Burm.f.) using gas chromatography-mass spectrometry.

    Science.gov (United States)

    Ganesh, Mani; Mohankumar, Murugan

    2017-09-01

    Sida cordata (Burm.f.) is a pineal tropical plant in the family Malvaceae that is found throughout India and used to treat various diseases and ailments in many complementary and alternative medicine systems. This study identified the bioactive components present in whole-plant ethanol extracts of S. cordata using gas chromatography-mass spectrometry (GC-MS). Based on their retention times (RT) and mass-to-charge ratios (m/z), 29 bioactive compounds were identified: nonanoic acid, vitamin D3, 3-trifluroacetoxypentadecane, α-d-glucopyranoside, O-α-d-glucopyranosyl-(1.fwdarw.3)-α-d-fructofuranosyl,3,7,11,15-tetramethyl-2-hexadecan-1-ol, octadecanoic acid, ethyl ester, phytol, 9,12-octadecadienoic acid, methyl ester (E,E), 9,12,15-octadecadienoic acid, methyl ester (Z,Z,Z), oleic acid, 1,2-15,16-diepoxyhexadecane, 3-hexadecyloxycarbonyl-5-(2-hydroxyethyl)-4-methylimidazolium ion, methoxyacetic acid, 4-tetradecyl ester, 1,2-benzenedicarboxylic acid, mono (2-ethylhexyl) ester, 1-iodo-2-methylundecane, dodecane, 2,6,10-trimethyl-, 2-piperidinone-N-[4-bromo-n-butyl]-, squalene, octadecane-1-(ethenyloxy)-, Z,Z-2,5-pentadecadien-1-ol, 1-hexadecanol, 2-methyl-, spiro[androst-5ene-17,1'-cyclobutan]-2'-one-3-hydroxy-, (3a,17a)-, diethylene glycol monododecyl ether, vitamin E, cholestan-3-ol, 2-methylene-, (3a,5a)-, 2H-pyran, 2-(7-heptadecynyloxy)tetrahydro-, and cis-Z-α-bisabolene epoxide. The presence of various bioactive compounds justifies the use of this plant for treating various ailments by traditional practitioners.

  3. Effect of Some Heterocyclic Derivatives on the Removal of Copper Ions from Wastewater by Cementation

    Institute of Scientific and Technical Information of China (English)

    A.A. Taha; M.G.Marei; D.E.Abd El-khalek

    2004-01-01

    Removal of copper ions from copper sulphate solutions on a rotating zinc rod in absence and in presence of 3(2H)-furanones and 4H-pyran-4-one derivatives was investigated experimentally. Variables studied were initial copper ions concentration,rotational speed of the zinc rod, temperature and concentration of organic additives. It was found that cementation reaction is first order in presence and in absence of additives. Increasing concentration of initial copper ions, rotational speed of the zinc rod and temperature were found to increase the rate of cementation. In presence of organic additives an enhancement of the rate was observed, except in presence of methoxyfuranone the rate was found to decrease by an amount ranging from 11.74% to 33.79%. Rate acceleration or inhibition is associated mainly with changes in the structure of the additives as well as its concentration. The apparent activation energy for the cementation process in presence of different additives was estimated and was found to be ranged between 11.8 k J/mol and 25.95 k J/mol. These values suggest that the copper removal process in presence of these additives is controlled by diffusion. A scanning electron microscopy study of copper deposits obtained in presence of tolylfuranone, phenylpyrone and methoxyfuranone correlate with their behaviour during the kinetic study. Different reaction conditions and the physical properties of solutions were studied to obtain dimensionless correlation among all these parameters. It was found that on applying cementation reaction on a sample from industrial wastewater in presence of phenylpyrone about 91.9% of Cu2+ are removed.

  4. In vivo and in situ tracking cancer chemotherapy by highly photostable NIR fluorescent theranostic prodrug.

    Science.gov (United States)

    Wu, Xumeng; Sun, Xuanrong; Guo, Zhiqian; Tang, Jianbin; Shen, Youqing; James, Tony D; Tian, He; Zhu, Weihong

    2014-03-05

    In vivo monitoring of the biodistribution and activation of prodrugs is urgently required. Near infrared (NIR) fluorescence-active fluorophores with excellent photostability are preferable for tracking drug release in vivo. Herein, we describe a NIR prodrug DCM-S-CPT and its polyethylene glycol-polylactic acid (PEG-PLA) loaded nanoparticles as a potent cancer therapy. We have conjugated a dicyanomethylene-4H-pyran derivative as the NIR fluorophore with camptothecin (CPT) as the anticancer drug using a disulfide linker. In vitro experiments verify that the high intracellular glutathione (GSH) concentrations in tumor cells cause cleavage of the disulfide linker, resulting in concomitantly the active drug CPT release and significant NIR fluorescence turn-on with large Stokes shift (200 nm). The NIR fluorescence of DCM-S-CPT at 665 nm with fast response to GSH can act as a direct off-on signal reporter for the GSH-activatable prodrug. Particularly, DCM-S-CPT possesses much better photostability than ICG, which is highly desirable for in situ fluorescence-tracking of cancer chemotherapy. DCM-S-CPT has been successfully utilized for in vivo and in situ tracking of drug release and cancer therapeutic efficacy in living animals by NIR fluorescence. DCM-S-CPT exhibits excellent tumor-activatable performance when intravenously injected into tumor-bearing nude mice, as well as specific cancer therapy with few side effects. DCM-S-CPT loaded in PEG-PLA nanoparticles shows even higher antitumor activity than free CPT, and is also retained longer in the plasma. The tumor-targeting ability and the specific drug release in tumors make DCM-S-CPT as a promising prodrug, providing significant advances toward deeper understanding and exploration of theranostic drug-delivery systems.

  5. Elucidation of binding sites of dual antagonists in the human chemokine receptors CCR2 and CCR5.

    Science.gov (United States)

    Hall, Spencer E; Mao, Allen; Nicolaidou, Vicky; Finelli, Mattea; Wise, Emma L; Nedjai, Belinda; Kanjanapangka, Julie; Harirchian, Paymann; Chen, Deborah; Selchau, Victor; Ribeiro, Sofia; Schyler, Sabine; Pease, James E; Horuk, Richard; Vaidehi, Nagarajan

    2009-06-01

    Design of dual antagonists for the chemokine receptors CCR2 and CCR5 will be greatly facilitated by knowledge of the structural differences of their binding sites. Thus, we computationally predicted the binding site of the dual CCR2/CCR5 antagonist N-dimethyl-N-[4-[[[2-(4-methylphenyl)-6,7-dihydro-5H-benzohepten-8-yl] carbonyl]amino]benzyl]tetrahydro-2H-pyran-4-aminium (TAK-779), and a CCR2-specific antagonist N-(carbamoylmethyl)-3-trifluoromethyl benzamido-parachlorobenzyl 3-aminopyrrolidine (Teijin compound 1) in an ensemble of predicted structures of human CCR2 and CCR5. Based on our predictions of the protein-ligand interactions, we examined the activity of the antagonists for cells expressing thirteen mutants of CCR2 and five mutants of CCR5. The results show that residues Trp98(2.60) and Thr292(7.40) contribute significantly to the efficacy of both TAK-779 and Teijin compound 1, whereas His121(3.33) and Ile263(6.55) contribute significantly only to the antagonistic effect of Teijin compound 1 at CCR2. Mutation of residues Trp86(2.60) and Tyr108(3.32) adversely affected the efficacy of TAK-779 in antagonizing CCR5-mediated chemotaxis. Y49A(1.39) and E291A(7.39) mutants of CCR2 showed a complete loss of CCL2 binding and chemotaxis, despite robust cell surface expression, suggesting that these residues are critical in maintaining the correct receptor architecture. Modeling studies support the hypothesis that the residues Tyr49(1.39), Trp98(2.60), Tyr120(3.32), and Glu291(7.39) of CCR2 form a tight network of aromatic cluster and polar contacts between transmembrane helices 1, 2, 3, and 7.

  6. Density functional theory study of model complexes for the revised nitrate reductase active site in Desulfovibrio desulfuricans NapA.

    Science.gov (United States)

    Hofmann, Matthias

    2009-09-01

    [Mo(SSCH3)(S2C2(CH3)2)2](x) complexes with charges x between -3 and +3 were investigated by density functional theory computations as minimal nitrate reductase active-site models. The strongly reduced species (x = -2, -3) exist preferentially as pentacoordinate sulfo complexes separated from a thiolate anion. The oxidized extremes (x > 0) clearly prefer hexacoordinate complexes with an eta(2)-MeSS ligand. Among the neutral and especially for the singly negatively charged species structures with eta(2)-MeSS and eta(1)-MeSS ligands are energetically close to the sulfo methyl sulfide complex without SS bonding. For x = -1 the three isomers lie in a 1.5 kcal mol(-1) energy range. Putative mechanistic pathways for nitrate reduction from the literature were investigated computationally: (1) reduction at a pentacoordinate sulfo complex, (2) reduction at the ligand, and (3) reduction at the molybdenum center with an R-S-S ligand. All three pathways could be traced at least for some overall charges but no definite conclusion can be drawn about the mechanism. Complexes with larger dithiolato ligands were also computed in order to model the tricyclic metallopterin framework more accurately: the first heterocyclus (5,6-dihydro-2H-pyran) stabilizes the nitrate complex and the molybdenum oxo product complex by approximately 10 kcal mol(-1) and also reduces the activation barrier (by approximately 5 kcal mol(-1)). The effect of the second (1,2,3,4-tetrahydropyrazin) and third heterocyclus (2-amino-3H-pyrimidin-4-one) on the relative energies is relatively small. For bigger models derived from an experimental protein structure, nitrate reduction at a persulfo molybdenum(IV) complex fragment (mechanism 3) is clearly favored over the oxidation of a molybdenum-bound sulfur atom (mechanism 2). Mechanism 1 could not be investigated for the big models but seems the least favorable on the basis of the results from smaller models.

  7. Molecular host-guest energy-transfer system with an ultralow amplified spontaneous emission threshold employing an ambipolar semiconducting host matrix.

    Science.gov (United States)

    Toffanin, Stefano; Capelli, Raffaella; Hwu, Tsyr-Yuan; Wong, Ken-Tsung; Plötzing, Tobias; Först, Michael; Muccini, Michele

    2010-01-14

    We report on the characteristics of a host-guest lasing system obtained by coevaporation of an oligo(9,9-diarylfluorene) derivative named T3 with the red-emitter 4-(dicyanomethylene)-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran dye (DCM). We demonstrate that the ambipolar semiconductor T3 can be implemented as an active matrix in the realization of a host-guest system in which an efficient energy transfer takes place from the T3 matrix to the lasing DCM molecules. We performed a detailed spectroscopic study on the system by systematically varying the DCM concentration in the T3 matrix. Measurements of steady-state photoluminescence (PL), PL quantum yield (PLQY), time-resolved picosecond PL, and amplified spontaneous emission (ASE) threshold are used to optimize the acceptor concentration at which the ASE from DCM molecules takes place with the lowest threshold. The sample with a DCM relative deposition ratio of 2% shows an ASE threshold as low as 0.6 kW/cm(2) and a net optical gain measured by femtosecond time-resolved pump-and-probe spectroscopy as high as 77 cm(-1). The reference model system Alq(3):DCM sample measured in exactly the same experimental conditions presents an one-order-of-magnitude higher ASE threshold. The ASE threshold of T3:DCM is the lowest reported to date for a molecular host-guest energy-transfer system, which makes the investigated blend an appealing system for use as an active layer in lasing devices. In particular, the ambipolar charge transport properties of the T3 matrix and its field-effect characteristics make the host-guest system presented here an ideal candidate for the realization of electrically pumped organic lasers.

  8. Synthesis, spectral, thermal, potentiometric and antimicrobial studies of transition metal complexes of tridentate ligand

    Directory of Open Access Journals (Sweden)

    Sarika M. Jadhav

    2014-01-01

    Full Text Available A series of metal complexes of Cu(II, Ni(II, Co(II, Fe(III and Mn(II have been synthesized with newly synthesized biologically active tridentate ligand. The ligand was synthesized by condensation of dehydroacetic acid (3-acetyl-6-methyl-(2H pyran-2,4(3H-dione or DHA, o-phenylene diamine and fluoro benzaldehyde and characterized by elemental analysis, molar conductivity, magnetic susceptibility, thermal analysis, X-ray diffraction, IR, 1H-NMR, UV–Vis spectroscopy and mass spectra. From the analytical data, the stoichiometry of the complexes was found to be 1:2 (metal:ligand with octahedral geometry. The molar conductance values suggest the non-electrolyte nature of metal complexes. The IR spectral data suggest that the ligand behaves as a dibasic tridentate ligand with ONN donor atoms sequence towards central metal ion. Thermal behaviour (TG/DTA and kinetic parameters calculated by the Coats–Redfern and Horowitz–Metzger method suggest more ordered activated state in complex formation. To investigate the relationship between stability constants of metal complexes and antimicrobial activity, the dissociation constants of Schiff bases and stability constants of their binary metal complexes have been determined potentiometrically in THF–water (60:40% solution at 25 ± 1 °C and at 0.1 M NaClO4 ionic strength. The potentiometric study suggests 1:1 and 1:2 complexation. Antibacterial and antifungal activities in vitro were performed against Staphylococcus aureus, Escherichia coli and Aspergillus niger, Trichoderma, respectively. The stability constants of the metal complexes were calculated by the Irving–Rosotti method. A relation between the stability constant and antimicrobial activity of complexes has been discussed. It is observed that the activity enhances upon complexation and the order of antifungal activity is in accordance with stability order of metal ions.

  9. α-Terpineol reactions with the nitrate radical: Rate constant and gas-phase products

    Science.gov (United States)

    Jones, Brian T.; Ham, Jason E.

    The bimolecular rate constant of k rad +α-terpineol (16 ± 4) × 10 -12 cm 3 molecule -1 s -1 was measured using the relative rate technique for the reaction of the nitrate radical (NO 3rad ) with α-terpineol (2-(4-methyl-1-cyclohex-3-enyl)propan-2-ol) at 297 ± 3 K and 1 atmosphere total pressure. To more clearly define part of α-terpineol's indoor environment degradation mechanism, the products of α-terpineol + NO 3rad reaction were investigated. The identified reaction products were: acetone, glyoxal (HC( dbnd O)C( dbnd O)H), and methylglyoxal (CH 3C( dbnd O)C( dbnd O)H). The use of derivatizing agents O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine (PFBHA) and N, O-bis(trimethylsilyl) trifluoroacetamide (BSTFA) were used to propose the other major reaction products: 6-hydroxyhept-5-en-2-one, 4-(1-hydroxy-1-methylethyl)-1-methyl-2-oxocyclohexyl nitrate, 5-(1-hydroxy-1-methylethyl)-2-oxocyclohexyl nitrate, 1-formyl-5-hydroxy-4-(hydroxymethyl)-1,5-dimethylhexyl nitrate, and 1,4-diformyl-5-hydroxy-1,5-dimethylhexyl nitrate. The elucidation of these products was facilitated by mass spectrometry of the derivatized reaction products coupled with plausible α-terpineol + NO 3rad reaction mechanisms based on previously published volatile organic compound + NO 3rad gas-phase mechanisms. The additional gas-phase products (2,6,6-trimethyltetrahydro-2 H-pyran-2,5-dicarbaldehyde and 2,2-dimethylcyclohexane-1,4-dicarbaldehyde) are proposed to be the result of cyclization through a reaction intermediate.

  10. Pyranopterin Coordination Controls Molybdenum Electrochemistry in Escherichia coli Nitrate Reductase*

    Science.gov (United States)

    Wu, Sheng-Yi; Rothery, Richard A.; Weiner, Joel H.

    2015-01-01

    We test the hypothesis that pyranopterin (PPT) coordination plays a critical role in defining molybdenum active site redox chemistry and reactivity in the mononuclear molybdoenzymes. The molybdenum atom of Escherichia coli nitrate reductase A (NarGHI) is coordinated by two PPT-dithiolene chelates that are defined as proximal and distal based on their proximity to a [4Fe-4S] cluster known as FS0. We examined variants of two sets of residues involved in PPT coordination: (i) those interacting directly or indirectly with the pyran oxygen of the bicyclic distal PPT (NarG-Ser719, NarG-His1163, and NarG-His1184); and (ii) those involved in bridging the two PPTs and stabilizing the oxidation state of the proximal PPT (NarG-His1092 and NarG-His1098). A S719A variant has essentially no effect on the overall Mo(VI/IV) reduction potential, whereas the H1163A and H1184A variants elicit large effects (ΔEm values of −88 and −36 mV, respectively). Ala variants of His1092 and His1098 also elicit large ΔEm values of −143 and −101 mV, respectively. An Arg variant of His1092 elicits a small ΔEm of +18 mV on the Mo(VI/IV) reduction potential. There is a linear correlation between the molybdenum Em value and both enzyme activity and the ability to support anaerobic respiratory growth on nitrate. These data support a non-innocent role for the PPT moieties in controlling active site metal redox chemistry and catalysis. PMID:26297003

  11. Structural insights, protein-ligand interactions and spectroscopic characterization of isoformononetin

    Science.gov (United States)

    Srivastava, Anubha; Singh, Harshita; Mishra, Rashmi; Dev, Kapil; Tandon, Poonam; Maurya, Rakesh

    2017-04-01

    Isoformononetin, a methoxylated isoflavone present in medicinal plants, has non-estrogenic bone forming effect via differential mitogen-activated protein kinase (MAPK) signaling. Spectroscopic (FT-Raman, FT-IR, UV-vis and NMR spectra) and quantum chemical calculations using density functional theory (DFT) and 6-311++G(d,p) as a large basis set have been employed to study the structural and electronic properties of isoformononetin. A detailed conformational analysis is performed to determine the stability among conformers and the various possibilities of intramolecular hydrogen bonding formation. Molecular docking studies with different protein kinases were performed on isoformononetin and previously studied isoflavonoid, formononetin in order to understand their inhibitory nature and the effect of functional groups on osteogenic or osteoporosis associated proteins. It is found that the oxygen atoms of methoxy, hydroxyl groups attached to phenyl rings R1, R3 and carbonyl group attached to pyran ring R2, play a major role in binding with the protein kinases that is responsible for the osteoporosis; however, no hydrophobic interactions are observed between rings of ligand and protein. The electronic properties such as HOMO and LUMO energies were determined by time-dependent TD-DFT which predict that conformer II is a little bit more stable and chemically low reactive than conformer I of isoformononetin. To estimate the structure-activity relationship, the molecular electrostatic potential (MEP) surface map, and reactivity descriptors are calculated from the optimized geometry of the molecule. From these results, it is also found that isoformononetin is kinetically more stable, less toxic, weak electrophile and chemically less reactive than formononetin. The atoms in molecules and natural bond orbital analysis are applied for the detailed analysis of intra and intermolecular hydrogen bonding interactions.

  12. Biodegradation of benzo[a]pyrene in soil by Mucor sp. SF06 and Bacillus sp. SB02 co-immobilized on vermiculite

    Institute of Scientific and Technical Information of China (English)

    SU Dan; LI Pei-jun; FRANK Stagnitti; XIONG Xian-zhe

    2006-01-01

    Two indigenous microorganisms, Bacillus sp. SB02 and Mucor sp. SF06, capable of degrading polycyclic aromatic hydrocarbons (PAHs) were co-immobilized on vermiculite by physical adsorption and used to degrade benzo[a] pyrane (BaP). The characteristics of BaP degradation by both free and co-immobilized microorganism were then investigated and compared. The removal rate using the immobilized bacterial-ftmgal mixed consortium was higher than that of the freely mobile mixed consortium. 95.3% of BaP was degraded using the co-immobilized system within 42 d, which was remarkably higher than the removal rate of that by the free strains. The optimal amount of inoculated co-immobilized system for BaP degradation was 2%. The immobilized bacterial-ftmgal mixed consortium also showed better water stability than the free strains. Kinetics of BaP biodegradation by co-immobilized SF06 and SB02 were also studied. The results demonstrated that BaP degradation could be well described by a zero-order reaction rate equation when the initial BaP concentration was in the range of 10-200 mg/kg. The scanning electronic microscope (SEM) analysis showed that the co-immobilized microstructure was suitable for the growth of SF06 and SB02. The mass transmission process of co-immobilized system in soil is discussed. The results demonstrate the potential for employing the bacterial-fungal mixed consortium,co-immobilized on vermiculite, for in situ bioremediation of BaP.

  13. Synthesis of erbium,ytterbium-doped hexagonal phase sodium yttrium fluoride nanoparticles and application to ligand exchange and energy transfer studies

    Science.gov (United States)

    Goel, Vishya

    Nanoparticles containing rare earth ions have the ability to absorb and convert infrared light into visible light. The purpose of this work is to synthesize rare earth ion-doped NaYF4 nanoparticles in their most efficient form, the hexagonal phase. These nanoparticles are then used in ligand exchange and energy transfer studies. The synthesis procedure produces gram scale quantities of nanoparticles. Such a scale is important for reproducibility and application of these materials. Oleylamine-capped NaYF4 nanoparticles were synthesized and were doped with 2 % Er3+ and 20 % Yb3+ using a thermal decomposition method. The procedure was optimized in terms of precursor concentration and injection rate. The samples were characterized using photoluminescence spectroscopy, transmission electron microscopy, and X-ray diffraction. Photoluminescence spectra were collected using infrared excitation (980 nm). Control of the temperature and injection resulted in 15 nm (diameter) hexagonal phase NaYF4:Er3+,Yb3+ nanoparticles capped with oleylamine. The nanoparticles exhibited bright emission in the red (640 nm) and green (540 nm) portions of the visible spectrum. The surface of the nanoparticles was modified with decanoic acid, dodecanedioic acid, or dodecane sulfonic acid using a ligand exchange reaction. Energy transfer was studied from the oleylamine-capped nanoparticles to the fluorophores Nile Red, 4-(dicyanomethylene)-2-t-butyl-6(1,1,7,7-tetramethyljulolidyl-9-enyl)-4H-pyran, and poly(2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene vinylene). Successful surface ligand exchange was achieved and the preliminary exploration of upconverting nanoparticles as an energy transfer donor was performed.

  14. Pyridostigmine restores cardiac autonomic balance after small myocardial infarction in mice.

    Directory of Open Access Journals (Sweden)

    Marina T Durand

    Full Text Available The effect of pyridostigmine (PYR--an acetylcholinesterase inhibitor--on hemodynamics and cardiac autonomic control, was never studied in conscious myocardial infarcted mice. Telemetry transmitters were implanted into the carotid artery under isoflurane anesthesia. Seven to ten days after recovery from the surgery, basal arterial pressure and heart rate were recorded, while parasympathetic and sympathetic tone (ΔHR was evaluated by means of methyl atropine and propranolol. After the basal hemodynamic recording the mice were subjected to left coronary artery ligation for producing myocardial infarction (MI, or sham operation, and implantation of minipumps filled with PYR or saline. Separate groups of anesthetized (isoflurane mice previously (4 weeks subjected to MI, or sham coronary artery ligation, were submitted to cardiac function examination. The mice exhibited an infarct length of approximately 12%, no change in arterial pressure and increased heart rate only in the 1st week after MI. Vagal tone decreased in the 1st week, while the sympathetic tone was increased in the 1st and 4th week after MI. PYR prevented the increase in heart rate but did not affect the arterial pressure. Moreover, PYR prevented the increase in sympathetic tone throughout the 4 weeks. Concerning the parasympathetic tone, PYR not only impaired its attenuation in the 1st week, but enhanced it in the 4th week. MI decreased ejection fraction and increased diastolic and systolic volume. Therefore, the pharmacological increase of peripheral acetylcholine availability by means of PYR prevented tachycardia, increased parasympathetic and decreased sympathetic tone after MI in mice.

  15. Determination of Pyrolytic Products of Extract of Raisin by Py-GC-MS%热裂解气相色谱-质谱法测定葡萄干提取物的热裂解产物

    Institute of Scientific and Technical Information of China (English)

    赵国玲

    2012-01-01

    50g葡萄干用70%乙醇溶液300mL在80℃回流提取3h,提取两次,过滤提取物.滤液减压浓缩至干。残渣用5200裂解仪在400℃,50℃.600℃,800℃下处理,在各裂解温度下得到的裂解产物导入仪器进行气相色谱质谱分析。结果表明:主要裂解产物是糠醛、呋喃甲醇、5-甲基糠醛、5-羟甲基-2呋喃甲醛、2,3-二氢-3,5二羟基6-甲基-4H-吡喃酮,这些裂解产物是赋予卷烟具有独特香味和较好口感的重要物质。%50 g of raisin were exlracted twice by refluxing with 300 mI. of 70% ethanol at 80℃ for 3 h. The extracts wgre filtered and the filtrate was evaporated to dryness under reduced pressure. The residue was lrealed whh Pyroprohc 5200 at 400 C, 500℃, 600℃ and 800℃, the pyrolytic products obtained al eaeh of lhe pyrolylie tempuratures were introduced into the instrument and analyzed by (GC-MS. It was shown that the main pyrolytic products obtained were furfural, 2-furanmethanol, 5 mcthyl 2-furancarboxaldehyde, 5 hydroxymethyl 2 furancarboxaldehyde, and 2, 3-dihydro-3, 5 dihydroxy6methyl.-4H-pyran-4one. These pyrolysates are the important substances to make cigarettes to have distinctive fragrance and better taste.

  16. Logical design of an anti-cancer agent targeting the plant homeodomain in Pygopus2.

    Science.gov (United States)

    Ali, Ferdausi; Yamaguchi, Keiichi; Fukuoka, Mayuko; Elhelaly, Abdelazim Elsayed; Kuwata, Kazuo

    2016-09-01

    Pygopus2 (Pygo2) is a component of the Wnt signaling pathway, which is required for β-catenin mediated transcription. Plant homeodomain (PHD) finger in Pygo2 intercalates the methylated histone 3 (H3K4me) tail and HD1 domain of BCL9 that binds to β-catenin. Thus, PHD finger may be a potential target for the logical design of an anti-cancer drug. Here, we found that Spiro[2H-naphthol[1,2-b]pyran-2,4'-piperidine]-1'ethanol,3,4-dihydro-4-hydroxy-α-(6-methyl-1H-indol-3-yl)) termed JBC117 interacts with D339, A348, R356, V376 and A378 in PHD corresponding to the binding sites with H3K4me and/or HD1, and has strong anti-cancer effects. For colon (HCT116) and lung (A549) cancer cell lines, IC50 values were 2.6 ± 0.16 and 3.3 ± 0.14 μM, respectively, while 33.80 ± 0.15 μM for the normal human fibroblast cells. JBC117 potently antagonized the cellular effects of β-catenin-dependent activity and also inhibited the migration and invasion of cancer cells. In vivo studies showed that the survival time of mice was significantly prolonged by the subcutaneous injection of JBC117 (10 mg/kg/day). In conclusion, JBC117 is a novel anti-cancer lead compound targeting the PHD finger of Pygo2 and has a therapeutic effect against colon and lung cancer.

  17. A highly productive, whole-cell DERA chemoenzymatic process for production of key lactonized side-chain intermediates in statin synthesis.

    Directory of Open Access Journals (Sweden)

    Matej Ošlaj

    Full Text Available Employing DERA (2-deoxyribose-5-phosphate aldolase, we developed the first whole-cell biotransformation process for production of chiral lactol intermediates useful for synthesis of optically pure super-statins such as rosuvastatin and pitavastatin. Herein, we report the development of a fed-batch, high-density fermentation with Escherichia coli BL21 (DE3 overexpressing the native E. coli deoC gene. High activity of this biomass allows direct utilization of the fermentation broth as a whole-cell DERA biocatalyst. We further show a highly productive bioconversion processes with this biocatalyst for conversion of 2-substituted acetaldehydes to the corresponding lactols. The process is evaluated in detail for conversion of acetyloxy-acetaldehyde with the first insight into the dynamics of reaction intermediates, side products and enzyme activity, allowing optimization of the feeding strategy of the aldehyde substrates for improved productivities, yields and purities. The resulting process for production of ((2S,4R-4,6-dihydroxytetrahydro-2H-pyran-2-ylmethyl acetate (acetyloxymethylene-lactol has a volumetric productivity exceeding 40 g L(-1 h(-1 (up to 50 g L(-1 h(-1 with >80% yield and >80% chromatographic purity with titers reaching 100 g L(-1. Stereochemical selectivity of DERA allows excellent enantiomeric purities (ee >99.9%, which were demonstrated on downstream advanced intermediates. The presented process is highly cost effective and environmentally friendly. To our knowledge, this is the first asymmetric aldol condensation process achieved with whole-cell DERA catalysis and it simplifies and extends previously developed DERA-catalyzed approaches based on the isolated enzyme. Finally, applicability of the presented process is demonstrated by efficient preparation of a key lactol precursor, which fits directly into the lactone pathway to optically pure super-statins.

  18. Antinociceptive activity of extracts and secondary metabolites from wild growing and micropropagated plants of Renealmia alpinia

    Science.gov (United States)

    Gómez-Betancur, Isabel; Cortés, Natalie; Benjumea, Dora; Osorio, Edison; León, Francisco; Cutler, Stephen J.

    2015-01-01

    Ethnopharmacological relevance Renealmia alpinia is native to the American continent and can be found from Mexico to Brazil, and in the Caribbean islands. It is known as “matandrea” in Colombia, and it has been commonly used in traditional medicine to treat painful diseases and ailments. Based on its traditional uses, it is of interest to evaluate the pharmacologic effects of this plant and its secondary metabolites. Materials and methods Methanol and aqueous extracts of wild and micropropagated R. alpinia (leaves) were obtained and chemically compared by High Performance Thin Layer Chromatography (HPTLC). The antinociceptive activity of these extracts was examined using an in vivo assay (Siegmund test). Additionally, the dichloromethane extract of R. alpinia was fractionated and pure compounds were isolated by chromatographic methods. The structure elucidation of isolated compounds was performed by NMR experiments and spectroscopic techniques and comparison with the literature data. Purified compounds were evaluated for their in vitro binding affinity for opioids and cannabinoids receptors. Results The dichloromethane extract of the plant’s aerial part afforded sinostrobin (1), naringenin 7,4′-dimethyl ether (2), 2′,6′-dihydroxy-4′-methoxychalcone (3), 4-methoxy-6-(2-phenylethenyl)-2H-pyran-2-one (4), naringenin 7-methyl ether (5) and 3,5-heptanediol, 1,7-diphenyl (6), which were isolated using chromatographic methods. Their chemical structures were established by physical and spectroscopic techniques. The antinociceptive effects observed in mice by extracts of wild and micropropagated plants were similar. The compounds isolated from R. alpinia do not show affinity to opioid or cannabinoid receptors. Conclusion Aqueous and methanol extracts of R. alpinia provide antinociceptive and analgesic effects in an in vivo model. These results contribute additional insight as to why this plant is traditionally used for pain management. Also, this is the first

  19. Urolithins, ellagic acid-derived metabolites produced by human colonic microflora, exhibit estrogenic and antiestrogenic activities.

    Science.gov (United States)

    Larrosa, Mar; González-Sarrías, Antonio; García-Conesa, María Teresa; Tomás-Barberán, Francisco A; Espín, Juan Carlos

    2006-03-08

    Urolithins A and B (hydroxy-6H-dibenzo[b,d]pyran-6-one derivatives) are colonic microflora metabolites recently proposed as biomarkers of human exposure to dietary ellagic acid derivatives. Molecular models suggest that urolithins could display estrogenic and/or antiestrogenic activity. To this purpose, both urolithins and other known phytoestrogens (genistein, daidzein, resveratrol, and enterolactone) were assayed to evaluate the capacity to induce cell proliferation on the estrogen-sensitive human breast cancer MCF-7 cells as well as the ability to bind to alpha- and beta-estrogen receptors. Both urolithins A and B showed estrogenic activity in a dose-dependent manner even at high concentrations (40 microM), without antiproliferative or toxic effects, whereas the other phytoestrogens inhibited cell proliferation at high concentrations. Overall, urolithins showed weaker estrogenic activity than the other phytoestrogens. However, both urolithins displayed slightly higher antiestrogenic activity (antagonized the growth promotion effect of 17-beta-estradiol in a dose-dependent manner) than the other phytoestrogens. The IC(50) values for the ERalpha and ERbeta binding assays were 0.4 and 0.75 microM for urolithin A; 20 and 11 microM for urolithin B; 3 and 0.02 for genistein; and 2.3 and 1 for daidzein, respectively; no binding was detected for resveratrol and enterolactone. Urolithins A and B entered into MCF-7 cells and were metabolized to yield mainly urolithin-sulfate derivatives. These results, together with previous studies regarding absorption and metabolism of dietary ellagitannins and ellagic acid in humans, suggest that the gut microflora metabolites urolithins are potential endocrine-disrupting molecules, which could resemble other described "enterophytoestrogens" (microflora-derived metabolites with estrogenic/antiestrogenic activity). Further research is warranted to evaluate the possible role of ellagitannins and ellagic acid as dietary "pro-phytoestrogens".

  20. Pomegranate ellagitannin-derived metabolites inhibit prostate cancer growth and localize to the mouse prostate gland.

    Science.gov (United States)

    Seeram, Navindra P; Aronson, William J; Zhang, Yanjun; Henning, Susanne M; Moro, Aune; Lee, Ru-Po; Sartippour, Maryam; Harris, Diane M; Rettig, Matthew; Suchard, Marc A; Pantuck, Allan J; Belldegrun, Arie; Heber, David

    2007-09-19

    Our group has shown in a phase II clinical trial that pomegranate juice (PJ) increases prostate specific antigen (PSA) doubling time in prostate cancer (CaP) patients with a rising PSA. Ellagitannins (ETs) are the most abundant polyphenols present in PJ and contribute greatly towards its reported biological properties. On consumption, ETs hydrolyze to release ellagic acid (EA), which is then converted by gut microflora to 3,8-dihydroxy-6H-dibenzo[b, d]pyran-6-one (urolithin A, UA) derivatives. Despite the accumulating knowledge of ET metabolism in animals and humans, there is no available data on the pharmacokinetics and tissue disposition of urolithins. Using a standardized ET-enriched pomegranate extract (PE), we sought to further define the metabolism and tissue distribution of ET metabolites. PE and UA (synthesized in our laboratory) were administered to C57BL/6 wild-type male mice, and metabolite levels in plasma and tissues were determined over 24 h. ET metabolites were concentrated at higher levels in mouse prostate, colon, and intestinal tissues as compared to other tissues after administration of PE or UA. We also evaluated the effects of PE on CaP growth in severe combined immunodeficient (SCID) mice injected subcutaneously with human CaP cells (LAPC-4). PE significantly inhibited LAPC-4 xenograft growth in SCID mice as compared to vehicle control. Finally, EA and several synthesized urolithins were shown to inhibit the growth of human CaP cells in vitro. The chemopreventive potential of pomegranate ETs and localization of their bioactive metabolites in mouse prostate tissue suggest that pomegranate may play a role in CaP treatment and chemoprevention. This warrants future human tissue bioavailability studies and further clinical studies in men with CaP.

  1. Brazilin from Caesalpinia sappan heartwood and its pharmacological activities:A review

    Institute of Scientific and Technical Information of China (English)

    Nilesh P Nirmal; Mithun S Rajput; Rangabhatla GSV Prasad; Mehraj Ahmad

    2015-01-01

    Caesalpinia sappan L. (CS) is a plant of Leguminosae family, commonly known as Brazil or Sappan wood. CS is distributed in Southeast Asia and its dried heartwood has been used as traditional ingredient of food or beverages and has a wide variety of medicinal properties. Higher extraction yield of CS wood was achieved with 95% ethanol for 2 h. Chemical constituent’s investigation of sappan wood resulted in the isolation of various structural types of phenolic components including one xanthone, one coumarin, three chalcones, two flavones three homoisoflavonoids and brazilin. Brazilin [(6a S-cis)-7, 11b-dihydrobenz[b]indeno[1,2-d] pyran-3,6a,9,10(6H)-tetrol], a major and active compound found in CS heartwood. Most of the folkloric uses of brazilin were validated by the scientific studies such as antioxidant, antibacterial, anti-inflammatory, anti-photoaging, hypoglycemic, vasorelaxant, hepatoprotective and anti-acne activity. CS heartwood extract is safe and did not produce any acute or subacute toxicity in both male and female rats. Brazilin is the safe natural compound having potential to develop as a medicinal compound with application in food, beverage, cosmetics and pharmaceutical industries to screen its clinical use in modern medicine. The information gained could provide the important and potential approach for pharmaceutical researcher to implicate the knowledge of brazilin in the formulation of new drug and to reveal therapeutic and gaps requiring future research opportunities. More studies are needed to evaluate the potential application of brazilin as preservative and coloring agent in food processing industries.

  2. A competitive nucleotide binding inhibitor: in vitro characterization of Rab7 GTPase inhibition.

    Science.gov (United States)

    Agola, Jacob O; Hong, Lin; Surviladze, Zurab; Ursu, Oleg; Waller, Anna; Strouse, J Jacob; Simpson, Denise S; Schroeder, Chad E; Oprea, Tudor I; Golden, Jennifer E; Aubé, Jeffrey; Buranda, Tione; Sklar, Larry A; Wandinger-Ness, Angela

    2012-06-15

    Mapping the functionality of GTPases through small molecule inhibitors represents an underexplored area in large part due to the lack of suitable compounds. Here we report on the small chemical molecule 2-(benzoylcarbamothioylamino)-5,5-dimethyl-4,7-dihydrothieno[2,3-c]pyran-3-carboxylic acid (PubChem CID 1067700) as an inhibitor of nucleotide binding by Ras-related GTPases. The mechanism of action of this pan-GTPase inhibitor was characterized in the context of the Rab7 GTPase as there are no known inhibitors of Rab GTPases. Bead-based flow cytometry established that CID 1067700 has significant inhibitory potency on Rab7 nucleotide binding with nanomolar inhibitor (K(i)) values and an inhibitory response of ≥97% for BODIPY-GTP and BODIPY-GDP binding. Other tested GTPases exhibited significantly lower responses. The compound behaves as a competitive inhibitor of Rab7 nucleotide binding based on both equilibrium binding and dissociation assays. Molecular docking analyses are compatible with CID 1067700 fitting into the nucleotide binding pocket of the GTP-conformer of Rab7. On the GDP-conformer, the molecule has greater solvent exposure and significantly less protein interaction relative to GDP, offering a molecular rationale for the experimental results. Structural features pertinent to CID 1067700 inhibitory activity have been identified through initial structure-activity analyses and identified a molecular scaffold that may serve in the generation of more selective probes for Rab7 and other GTPases. Taken together, our study has identified the first competitive GTPase inhibitor and demonstrated the potential utility of the compound for dissecting the enzymology of the Rab7 GTPase, as well as serving as a model for other small molecular weight GTPase inhibitors.

  3. Characterization of Chemical Compounds with Antioxidant and Cytotoxic Activities in Bougainvillea x buttiana Holttum and Standl, (var. Rose Extracts

    Directory of Open Access Journals (Sweden)

    Rodolfo Abarca-Vargas

    2016-12-01

    Full Text Available Bougainvillea is widely used in traditional Mexican medicine to treat several diseases. This study was designed to characterize the chemical constituents of B. x buttiana extracts with antioxidant and cytotoxic activities using different solvents. The extraction solvents used were as follows: distilled water (dH2O, methanol (MeOH, acetone (DMK, ethanol (EtOH, ethyl acetate (EtOAc, dichloromethane (DCM, and hexane (Hex (100% at an extraction temperature of 26 °C. Analysis of bioactive compounds present in the B. x buttiana extracts included the application of common phytochemical screening assays, GC-MS analysis, and cytotoxicity and antioxidant assays. The results show that the highest extraction yield was observed with water and methanol. The maximum total phenolic content amount and highest antioxidant potential were obtained when extraction with methanol was used. With the exceptions of water and ethanol extractions, all other extracts showed cytotoxicity ranging between 31% and 50%. The prevailing compounds in water, methanol, ethanol, and acetone solvents were as follows: 4H-pyran-4-one, 2,3-dihydro-3, 5-dihydroxy-6-methyl (2, 2-propenoic acid, 3-(2-hydrophenyl-(E- (3, and 3-O-methyl-d-glucose (6. By contrast, the major components in the experiments using solvents such as EtOH, DMK, EtOAc, DCM, and Hex were n-hexadecanoic acid (8, 9,12-octadecadienoic acid (Z,Z (12; 9-octadecenoic acid (E- (13, and stigmasta-5,22-dien-3-ol (28.

  4. QSAR analysis on Spodoptera litura antifeedant activities for flavone derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Duchowicz, Pablo R., E-mail: pabloducho@gmail.com [Instituto de Investigaciones Fisicoquimicas Teoricas y Aplicadas INIFTA (UNLP, CCT La Plata-CONICET), Diag. 113 y 64, Sucursal 4, C.C. 16, 1900 La Plata (Argentina); Goodarzi, Mohammad [Instituto de Investigaciones Fisicoquimicas Teoricas y Aplicadas INIFTA (UNLP, CCT La Plata-CONICET), Diag. 113 y 64, Sucursal 4, C.C. 16, 1900 La Plata (Argentina); Ocsachoque, Marco A. [Centro de Investigacion y Desarrollo en Ciencias Aplicadas ' Dr. J. J. Ronco' (CINDECA), Departamento de Quimica, Facultad de Ciencias Exactas, UNLP-CONICET. Calle 47 No 257, B1900AJK La Plata (Argentina); Romanelli, Gustavo P. [Centro de Investigacion y Desarrollo en Ciencias Aplicadas ' Dr. J. J. Ronco' (CINDECA), Departamento de Quimica, Facultad de Ciencias Exactas, UNLP-CONICET. Calle 47 No 257, B1900AJK La Plata (Argentina); Catedra de Quimica Organica, Facultad de Ciencias Agrarias y Forestales, UNLP. Calles 60 y 119, B1904AAN La Plata (Argentina); Ortiz, Erlinda del V. [Facultad de Tecnologia y Ciencias Aplicadas, Universidad Nacional de Catamarca, Av. Maximio Victoria 55, (4700), Catamarca (Argentina); Autino, Juan C.; Bennardi, Daniel O.; Ruiz, Diego M. [Catedra de Quimica Organica, Facultad de Ciencias Agrarias y Forestales, UNLP. Calles 60 y 119, B1904AAN La Plata (Argentina); Castro, Eduardo A. [Instituto de Investigaciones Fisicoquimicas Teoricas y Aplicadas INIFTA (UNLP, CCT La Plata-CONICET), Diag. 113 y 64, Sucursal 4, C.C. 16, 1900 La Plata (Argentina)

    2009-12-20

    We establish useful models that relate experimentally measured biological activities of compounds to their molecular structure. The pED{sub 50} feeding inhibition on Spodoptera litura species exhibited by aurones, chromones, 3-coumarones and flavones is analyzed in this work through the hypothesis encompassed in the Quantitative Structure-Activity Relationships (QSAR) Theory. This constitutes a first necessary computationally based step during the design of more bio-friendly repellents that could lead to insights for improving the insecticidal activities of the investigated compounds. After optimizing the molecular structure of each furane and pyrane benzoderivative with the semiempirical molecular orbitals method PM3, more than a thousand of constitutional, topological, geometrical and electronic descriptors are calculated and multiparametric linear regression models are established on the antifeedant potencies. The feature selection method employed in this study is the Replacement Method, which has proven to be successful in previous analyzes. We establish the QSAR both for the complete molecular set of compounds and also for each chemical class, so that acceptably describing the variation of the inhibitory activities from the knowledge of their structure and thus achieving useful predictive results. The main interest of developing trustful QSAR models is that these enable the prediction of compounds having no experimentally measured activities for any reason. Therefore, the structure-activity relationships are further employed for investigating the antifeedant activity on previously synthesized 2-,7-substituted benzopyranes, which do not pose any measured values on the biological expression. One of them, 2-({alpha}-naphtyl)-4H-1-benzopyran-4-one, results in a promising structure to be experimentally analyzed as it has predicted pED{sub 50} = 1.162.

  5. Karrikins discovered in smoke trigger Arabidopsis seed germination by a mechanism requiring gibberellic acid synthesis and light.

    Science.gov (United States)

    Nelson, David C; Riseborough, Julie-Anne; Flematti, Gavin R; Stevens, Jason; Ghisalberti, Emilio L; Dixon, Kingsley W; Smith, Steven M

    2009-02-01

    Discovery of the primary seed germination stimulant in smoke, 3-methyl-2H-furo[2,3-c]pyran-2-one (KAR1), has resulted in identification of a family of structurally related plant growth regulators, karrikins. KAR1 acts as a key germination trigger for many species from fire-prone, Mediterranean climates, but a molecular mechanism for this response remains unknown. We demonstrate that Arabidopsis (Arabidopsis thaliana), an ephemeral of the temperate northern hemisphere that has never, to our knowledge, been reported to be responsive to fire or smoke, rapidly and sensitively perceives karrikins. Thus, these signaling molecules may have greater significance among angiosperms than previously realized. Karrikins can trigger germination of primary dormant Arabidopsis seeds far more effectively than known phytohormones or the structurally related strigolactone GR-24. Natural variation and depth of seed dormancy affect the degree of KAR1 stimulation. Analysis of phytohormone mutant germination reveals suppression of KAR1 responses by abscisic acid and a requirement for gibberellin (GA) synthesis. The reduced germination of sleepy1 mutants is partially recovered by KAR1, which suggests that germination enhancement by karrikin is only partly DELLA dependent. While KAR1 has little effect on sensitivity to exogenous GA, it enhances expression of the GA biosynthetic genes GA3ox1 and GA3ox2 during seed imbibition. Neither abscisic acid nor GA levels in seed are appreciably affected by KAR1 treatment prior to radicle emergence, despite marked differences in germination outcome. KAR1 stimulation of Arabidopsis germination is light-dependent and reversible by far-red exposure, although limited induction of GA3ox1 still occurs in the dark. The observed requirements for light and GA biosynthesis provide the first insights into the karrikin mode of action.

  6. The Effect of Tea Polyphenol on Volatile Flavor Compounds in Pickled Cabbage during Shelf Life%茶多酚对货架期泡菜气味成分的影响

    Institute of Scientific and Technical Information of China (English)

    王向阳; 董欢欢; 俞兴伟

    2016-01-01

    茶多酚在腌菜中防腐效果好,为了解茶多酚对货架期泡菜气味的影响,在泡菜液中添加0.18%茶多酚,采用固相微萃取与气相质谱色谱联用法(SPME-MS/GC),分析泡菜的气味成分变化。结果表明:茶多酚抑制乳酸菌生长量,泡菜的主要风味物质是酮、酸、酯、醛、烯、醇。其中3-乙酰-4-羟基-6-甲基-2H-吡喃-2-酮、苯甲酸类、烯丙基异硫氰酸酯、壬醛、石竹烯、1-辛烯-3-醇是含量较高的气味成分。泡菜后期醛类、酯类比例显著上升。另外,苯衍生物、烯、烷、萘类也有较多比例增加。壬醛、癸醛、烯丙基异硫氰酸酯、丁酸-3-甲基丁酯的大量增加可能是引起泡菜后期异味的主要原因。苯衍生物、烯、萘类增加可能也促进异味。茶多酚处理大幅度降低酸类、酮类,降低后期酯类、醛类,提高醇类和后期烯类,导致其他类中咔唑类消失,蒽醌物质上升,腙类消失,酚类出现。茶多酚处理显著降低了3-乙酰-4-羟基-6-甲基-2H-吡喃-2-酮、苯甲酸类、异硫氰酸酯、壬醛,显著提升了后期 D-柠檬烯。茶多酚处理泡菜后期主要气味物质是 D-柠檬烯、3-乙酰-4-羟基-6-甲基-2H-吡喃-2-酮、1-辛烯-3-醇。%Tea polyphenols is an excellent preservative for pickles.To find out the effects of tea polyphenols on the smell of pickle during shelf life,tea polyphenols (0.18%,W/V)is added into pickled cabbage.The change of volatile components of pickled cabbage is analyzed with solid phase micro-extraction and gas chromatography-mass spectrometry (SPME-GC/MS).The results show that tea polyphenols inhibit the growth of lactic acid bacteria,the main flavor compounds of pickled cabbage are ketones,acids,esters,aldehydes,alkenes and alcohols.The main odors components are 3-acetyl-4-hydroxy-6-methyl-2H-pyran-2-one,benzoic acids,allyl isothiocyanate,nonanal,caryophyllene and 1-octene-3-alcohol

  7. Crystal structures of two substituted thia-zolidine derivatives.

    Science.gov (United States)

    Viswanathan, Vijayan; Rao, Naga Siva; Raghunathan, Raghavachary; Velmurugan, Devadasan

    2016-08-01

    In the first of the compounds reported herein, namely 6'-ferrocenyl-6a'-nitro-6',6a',6b',7',9',11a'-hexa-hydro-2H-spiro-[ace-naphthyl-ene-1,11'-chromeno[3',4':3,4]pyrrolo-[1,2-c]thia-zol]-2-one, [Fe(C5H5)(C29H21N2O4S)], (I), the thia-zolidine ring adopts a twist conformation on the methine N-C atoms. In the second compound, viz. 6'-(4-methoxy-phen-yl)-6a'-nitro-6',6a',6b',7',9',11a'-hexa-hydro-2H-spiro-[ace-naphthyl-ene-1,11'-chromeno[3',4':3,4]pyrrolo-[1,2-c]thia-zol]-2-one, [Fe(C5H5)(C26H19N2O5S)], (II), the thia-zolidine ring adopts an envelope conformation with a methine C atom as the flap. In both compounds, the pyrrolidine ring adopts a twist conformation on the thia-zolidine and tetra-hydro-pyran C atoms. The mean planes of the thia-zolidine and pyrrolidine rings subtend angles of 67.30 (1) and 62.95 (7)° in (I) and (II), respectively, while the mean plane of the pyrrolidine ring makes dihedral angles of 76.53 (1) and 87.74 (7)° with the ace-naphthyl-ene ring system in (I) and (II), respectively. In both compounds, an intra-molecular C-H⋯O hydrogen bond forms an S(7) ring motif. In the crystal of (I), mol-ecules are linked via two different C-H⋯O hydrogen bonds, forming chains along [001] and [100]. In (II), they are linked through C-H⋯O hydrogen bonds, forming dimers with an R 2 (2)(10) ring motif while C-H⋯π inter-actions link the mol-ecules in a head-to-tail fashion, forming chains along the a-axis direction.

  8. Crystal structures of two substituted thia­zolidine derivatives

    Science.gov (United States)

    Viswanathan, Vijayan; Rao, Naga Siva; Raghunathan, Raghavachary; Velmurugan, Devadasan

    2016-01-01

    In the first of the compounds reported herein, namely 6′-ferrocenyl-6a′-nitro-6′,6a′,6b′,7′,9′,11a′-hexa­hydro-2H-spiro­[ace­naphthyl­ene-1,11′-chromeno[3′,4′:3,4]pyrrolo­[1,2-c]thia­zol]-2-one, [Fe(C5H5)(C29H21N2O4S)], (I), the thia­zolidine ring adopts a twist conformation on the methine N—C atoms. In the second compound, viz. 6′-(4-methoxy­phen­yl)-6a′-nitro-6′,6a′,6b′,7′,9′,11a′-hexa­hydro-2H-spiro­[ace­naphthyl­ene-1,11′-chromeno[3′,4′:3,4]pyrrolo­[1,2-c]thia­zol]-2-one, [Fe(C5H5)(C26H19N2O5S)], (II), the thia­zolidine ring adopts an envelope conformation with a methine C atom as the flap. In both compounds, the pyrrolidine ring adopts a twist conformation on the thia­zolidine and tetra­hydro­pyran C atoms. The mean planes of the thia­zolidine and pyrrolidine rings subtend angles of 67.30 (1) and 62.95 (7)° in (I) and (II), respectively, while the mean plane of the pyrrolidine ring makes dihedral angles of 76.53 (1) and 87.74 (7)° with the ace­naphthyl­ene ring system in (I) and (II), respectively. In both compounds, an intra­molecular C—H⋯O hydrogen bond forms an S(7) ring motif. In the crystal of (I), mol­ecules are linked via two different C—H⋯O hydrogen bonds, forming chains along [001] and [100]. In (II), they are linked through C—H⋯O hydrogen bonds, forming dimers with an R 2 2(10) ring motif while C—H⋯π inter­actions link the mol­ecules in a head-to-tail fashion, forming chains along the a-axis direction. PMID:27536396

  9. Cannabinoid Type-2 Receptor Drives Neurogenesis and Improves Functional Outcome After Stroke.

    Science.gov (United States)

    Bravo-Ferrer, Isabel; Cuartero, María I; Zarruk, Juan G; Pradillo, Jesús M; Hurtado, Olivia; Romera, Víctor G; Díaz-Alonso, Javier; García-Segura, Juan M; Guzmán, Manuel; Lizasoain, Ignacio; Galve-Roperh, Ismael; Moro, María A

    2017-01-01

    Stroke is a leading cause of adult disability characterized by physical, cognitive, and emotional disturbances. Unfortunately, pharmacological options are scarce. The cannabinoid type-2 receptor (CB2R) is neuroprotective in acute experimental stroke by anti-inflammatory mechanisms. However, its role in chronic stroke is still unknown. Stroke was induced by permanent middle cerebral artery occlusion in mice; CB2R modulation was assessed by administering the CB2R agonist JWH133 ((6aR,10aR)-3-(1,1-dimethylbutyl)-6a,7,10,10a-tetrahydro-6,6,9-trimethyl-6H-dibenzo[b,d]pyran) or the CB2R antagonist SR144528 (N-[(1S)-endo-1,3,3-trimethylbicyclo-[2.2.1]-heptan-2-yl]-5-(4-chloro-3-methylphenyl)-1-(4-methylbenzyl)-pyrazole-3-carboxamide) once daily from day 3 to the end of the experiment or by CB2R genetic deletion. Analysis of immunofluorescence-labeled brain sections, 5-bromo-2´-deoxyuridine (BrdU) staining, fluorescence-activated cell sorter analysis of brain cell suspensions, and behavioral tests were performed. SR144528 decreased neuroblast migration toward the boundary of the infarct area when compared with vehicle-treated mice 14 days after middle cerebral artery occlusion. Consistently, mice on this pharmacological treatment, like mice with CB2R genetic deletion, displayed a lower number of new neurons (NeuN(+)/BrdU(+) cells) in peri-infarct cortex 28 days after stroke when compared with vehicle-treated group, an effect accompanied by a worse sensorimotor performance in behavioral tests. The CB2R agonist did not affect neurogenesis or outcome in vivo, but increased the migration of neural progenitor cells in vitro; the CB2R antagonist alone did not affect in vitro migration. Our data support that CB2R is fundamental for driving neuroblast migration and suggest that an endocannabinoid tone is required for poststroke neurogenesis by promoting neuroblast migration toward the injured brain tissue, increasing the number of new cortical neurons and, conceivably, enhancing

  10. Infrared matrix-isolation and theoretical studies of the reactions of ferrocene with ozone.

    Science.gov (United States)

    Kugel, Roger W; Pinelo, Laura F; Ault, Bruce S

    2015-03-19

    The reactions between ferrocene (Cp2Fe) (2a) and ozone (O3) were studied using low-temperature matrix-isolation techniques coupled with theoretical density functional theory (DFT) calculations. Co-deposition of Ar/Cp2Fe and Ar/O3 gas mixtures onto a cryogenically cooled CsI window produced a dark-green charge-transfer complex, Cp2Fe-O3, that photodecomposed upon red (λ ≥ 600 nm) and infrared (λ ≥ 1000 nm) irradiation but was stable to green or blue irradiation. Products of photodecomposition were characterized by FT-IR, oxygen-18 labeling, and DFT calculations using the B3LYP functionals and the 6-311G++(d,2p) basis set. Likely, photochemical products included four structures having the molecular formula C10H10FeO, identified by DFT calculations based on their calculated infrared spectra and (18)O isotope shifts. Each of these calculated molecules had one intact and fully coordinated η(5)-C5H5 cyclopentadienyl (Cp) ring and (1) an η(5)-C5H5O cyclic ether (pyran ring) (2b), (2) an η(4)-C5H5O linear aldehyde (2c), (3) a bidentate cyclic aldehyde with a seven-membered ring including the iron atom (2d), or (4) an Fe-O bond and an η(2)-C5H5 (Cp) ring (2e). No conclusive evidence for a gas-phase thermal reaction between ferrocene and ozone was observed under the conditions of these experiments. However, strong evidence for a surface-catalyzed thermal reaction was observed in merged-jet experiments wherein the gases were premixed before deposition. Surface-catalyzed ferrocene-ozone reaction products included a thin film of Fe2O3 observed on the walls of the merged tube as well as cyclopentadiene (C5H6), cyclopentadienone (C5H4O), and further oxidation products observed in the matrix. Possible mechanisms for both the photochemical and the thermal reactions are discussed.

  11. Occupancy of Nociceptin/Orphanin FQ Peptide Receptors by the Antagonist LY2940094 in Rats and Healthy Human Subjects.

    Science.gov (United States)

    Raddad, Eyas; Chappell, Amy; Meyer, Jeffery; Wilson, Alan; Ruegg, Charles E; Tauscher, Johannes; Statnick, Michael A; Barth, Vanessa; Zhang, Xin; Verfaille, Steven J

    2016-09-01

    Therapeutic benefits from nociceptin opioid peptide receptor (NOP) antagonism were proposed for obesity, eating disorders, and depression. LY2940094 ([2-[4-[(2-chloro-4,4-difluoro-spiro[5H-thieno[2,3-c]pyran-7,4'-piperidine]-1'-yl)methyl]-3-methyl-pyrazol-1-yl]-3-pyridyl]methanol) is a novel, orally bioavailable, potent, and selective NOP antagonist. We studied NOP receptor occupancy (RO) after single oral LY2940094 doses in rat hypothalamus and human brain by use of liquid chromatography with tandem mass spectrometry (LC-MS/MS) (LSN2810397) and positron emission tomography (PET) ([(11)C]NOP-1A) tracers, respectively. A bolus plus constant infusion tracer protocol with PET was employed in humans at 2.5 and 26.5 hours after administration of the LY2940094 dose. The RO was calculated from the change in regional distributional volume (VT) corrected for nondisplaceable volume using Lasson plots. The RO followed a simple Emax relationship to plasma LY2940094 concentration, reaching near complete occupancy in both species. For rat hypothalamus, the plasma concentration at half-maximum RO (EC50) was 5.8 ng/ml. In humans, LY2940094 was well tolerated and safe over the 4-40 mg dose range, and it peaked in plasma at 2 to 6 hours after a 1- to 2-hour lag, with approximate dose-proportional exposure. After 4-40 mg doses, NOP RO was similar across the prefrontal cortex, occipital cortex, putamen, and thalamus, with EC50 of 2.94 to 3.46 ng/ml, less than 2-fold lower than in rats. Over 4-40 mg doses, LY2940094 mean plasma levels at peak and 24 hours were 7.93-102 and 1.17-14.1 ng/ml, corresponding to the cross-region average NOP RO of 73%-97% and 28%-82%, respectively. The rat EC50 translates well to humans. LY2940094 readily penetrates the human brain, and a once-daily oral dose of 40 mg achieves sustainably high (>80%) NOP RO levels suitable for testing clinical efficacy.

  12. The Genus Aloe: Phytochemistry and Therapeutic Uses Including Treatments for Gastrointestinal Conditions and Chronic Inflammation.

    Science.gov (United States)

    Cock, I E

    2015-01-01

    Plants of the genus Aloe have perhaps the longest recorded history of medicinal usage and are amongst the most widely used plants for traditional medicinal purposes worldwide. Aloe vera, Aloe ferox, Aloe arborescens and Aloe perryi are the best known and most widely used, but many other species are also used for their therapeutic properties. The Aloes have been used since ancient times, particularly for the treatment of microbial infections, gastrointestinal disorders and inflammatory conditions. In addition to their myriad uses in traditional therapeutics, the Aloes have also been used as components of cosmetic formulations, and in the food and beverage industries. Despite their wide acceptance, studies from different laboratories often report wide variations in the therapeutic bioactivities from within the same Aloe species, even when the same extraction procedures are used. Furthermore, leaves from individual Aloe plants within the same species may have widely varying levels of the bioactive phytochemicals. Phytochemical analyses have shown that many Aloe species contain various carbohydrate polymers (notably glucomannans) and a range of other low molecular weight phenolic compounds including alkaloids, anthraquinones, anthrones, benzene and furan derivatives, chromones, coumarins, flavonoids, phytosterols, pyrans and pyrones. There has been a wealth of information published about the phytochemistry and therapeutic potential of the Aloes (especially Aloe vera). Much of this has been contradictory. Intra- and interspecies differences in the redox state of the individual Aloe components and in the ratios of these components may occur between individual plants. These factors may all affect the physiological properties of Aloe extracts. Due to the structure and chemical nature of many of the Aloe phytochemicals, it is likely that many of the reported medicinal properties are due to antioxidant or prooxidant effects. The antioxidant/prooxidant activities of many Aloe

  13. Materials Design via Optimized Intramolecular Noncovalent Interactions for High-Performance Organic Semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Xiaojie; Liao, Qiaogan; Manley, Eric F.; Wu, Zishan; Wang, Yulun; Wang, Weida; Yang, Tingbin; Shin, Young-Eun; Cheng, Xing; Liang, Yongye; Chen, Lin X.; Baeg, Kang-Jun; Marks, Tobin J.; Guo, Xugang

    2016-03-15

    We report the design, synthesis, and implemention in semiconducting polymers of a novel head-to-head linkage containing the TRTOR (3-alkyl-3'-alkoxy-2,2'-bithiophene) donor subunit having a single strategically optimized, planarizing noncovalent S···O interaction. Diverse complementary thermal, optical, electrochemical, X-ray scattering, electrical, photovoltaic, and electron microscopic characterization techniques are applied to establish structure-property correlations in a TRTOR-based polymer series. In comparison to monomers having double S···O interactions, replacing one alkoxy substituent with a less electron-donating alkyl one yields TRTOR-based polymers with significantly depressed (0.2-0.3 eV) HOMOs. Furthermore, the weaker single S···O interaction and greater TRTOR steric encumberance enhances materials processability without sacrificing backbone planarity. From another perspective, TRTOR has comparable electronic properties to ring-fused 5Hdithieno[ 3,2-b:2',3'-d]pyran (DTP) subunits, but a centrosymmetric geometry which promotes a more compact and ordered structure than bulkier, axisymmetric DTP. Compared to monosubstituted TTOR (3-alkoxy-2,2'-bithiophene), alkylation at the TRTOR bithiophene 3-position enhances conjugation and polymer crystallinity with contracted π-π stacking. Grazing incidence wide-angle X-ray scattering (GIWAXS) data reveal that the greater steric hindrance and the weaker single S···O interaction are not detrimental to close packing and high crystallinity. As a proof of materials design, copolymerizing TRTOR with phthalimides yields copolymers with promising thin-film transistor mobility as high as 0.42 cm2/(V·s) and 6.3% power conversion efficiency in polymer solar cells, the highest of any phthalimide copolymers reported to date. The depressed TRTOR HOMOs imbue these polymers with substantially increased Ion/Ioff ratios and Voc’s versus analogous subunits with multiple electron donating

  14. Methods for the synthesis of polyhydroxylated piperidines by diastereoselective dihydroxylation: Exploitation in the two-directional synthesis of aza-C-linked disaccharide derivatives

    Directory of Open Access Journals (Sweden)

    Nelson Adam

    2005-08-01

    Full Text Available Abstract Background: Many polyhydroxylated piperidines are inhibitors of the oligosaccharide processing enzymes, glycosidases and glycosyltransferases. Aza-C-linked disaccharide mimetics are compounds in which saturated polyhydroxylated nitrogen and oxygen heterocycles are linked by an all-carbon tether. The saturated oxygen heterocycle has the potential to mimic the departing sugar in a glycosidase-catalysed reaction and aza-C-linked disaccharide mimetics may, therefore, be more potent inhibitors of these enzymes. Results: The scope, limitations and diastereoselectivity of the dihydroxylation of stereoisomeric 2-butyl-1-(toluene-4-sulfonyl-1,2,3,6-tetrahydro-pyridin-3-ols is discussed. In the absence of a 6-substituent on the piperidine ring, the Upjohn (cat. OsO4, NMO, acetone-water and Donohoe (OsO4, TMEDA, CH2Cl2 conditions allow complementary diastereoselective functionalisation of the alkene of the (2R*,3R* diastereoisomer. However, in the presence of a 6-substituent, the reaction is largely controlled by steric effects with both reagents. The most synthetically useful protocols were exploited in the two-directional synthesis of aza-C-linked disaccharide analogues. A two-directional oxidative ring expansion was used to prepare bis-enones such as (2R,6S,2'S-6-methoxy-2-(6-methoxy-3-oxo-3,6-dihydro-2H-pyran-2-ylmethyl-1-(toluene-4-sulfonyl-1,6-dihydro-2H-pyridin-3-one from the corresponding difuran. Selective substitution of its N,O acetal was possible. The stereochemical outcome of a two-directional Luche reduction step was different in the two heterocyclic rings, and depended on the conformation of the ring. Finally, two-directional diastereoselective dihydroxylation yielded seven different aza-C-linked disaccharide analogues. Conclusion: A two-directional approach may be exploited in the synthesis of aza-C-linked disaccharide mimetics. Unlike previous approaches to similar molecules, neither of the heterocyclic rings is directly derived

  15. Detection of Volatile Aroma Compounds of Morchella by Headspace Gas Chromatography Mass Spectrometry (HS-GC/MS

    Directory of Open Access Journals (Sweden)

    Hatira TAŞKIN

    2013-05-01

    Full Text Available   This study was conducted at the Horticulture Department of Çukurova University, Adana, Turkey, in 2010 to determine the volatile aroma compounds of Morchella mushroom. Fresh samples of Morchella esculenta (Sample 1 and Morchella elata (Sample 2 were collected from Çanakkale (Sample 1 and Mersin (Sample 2 provinces in Turkey in the spring of 2010. Volatile aroma compounds were analyzed by headspace gas chromatography mass spectrometry (HS-GC/MS. A total of 31 aroma compounds were identified in the 2 analyzed samples: 7 alcohols, 7 esters, 7 ketones, 3 acids, 2 aldehydes, 1 terpene, phenol, 1-propanamine, geranyl linalool, and quinoline. Seventeen aroma components were identified in Sample 1, and 18 compounds were found in Sample 2. Phenol was determined as the major aroma compound in both Sample 1 and Sample 2, at 50.888% and 58.293% content, respectively. Alcohols, especially 1-octen-3-ol, were detected as the second major aroma components in Sample 1 and Sample 2, at 15.500% and 5.660% content, respectively. Carbamic acid, methyl ester was found only in Sample 1, at 11.379% content. The aroma components detected in the two samples differed. 1-Octadecanol; cyclooctylalcohol; trans-2-undecen-1-ol; butanoic acid, butyl ester (CAS; carbamic acid, methyl ester; 2-ethylhexyl-2-ethylhexanoate; phthalic acid, decyl isobutyl ester; 2,2,4-trimethyl-1,3-pentanediol diisobutyrate; decanal; nonanal; 7,9-di-tert-butyl-1-oxaspiro(4.5deca-6,9-diene-2,8-dione; 2,5-cyclohexadiene-1,4-dione; 2,6-bis(1,1-dimethylethyl; and trans-alpha-bisabolene were detected only in Sample 1. Ethanol; silanediol, 2-methylaminoethanol; L-alanine, ethyl ester; carbonic acid, dodecyl isobutyl ester; acetic acid; butanoic acid; 2,3,4H-pyran-4-one; 5,9-undecadien-2-one; cyclooctene; 2-cyclopenten-1-one; 1-propanamine; geranyl linalool; and quinoline were determined only in Sample 2.

  16. 异端基遥爪聚乙二醇的合成%Synthesis of hetero telechelic poly(ethylene glycol)

    Institute of Scientific and Technical Information of China (English)

    杨钊; 郝建原

    2012-01-01

    采用3种新式引发剂,即2-(苄氧基)乙醇钾、2-(四氢-2H-吡喃-2-氧基)乙醇钾、单丙烯基乙二醇钾引发环氧乙烷阴离子开环聚合,反应条件为25℃、48 h、醇与萘钾摩尔比例1∶1,得到3种异端基遥爪聚乙二醇。以2-(苄氧基)乙醇钾引发聚合所得产物为起始物,经一系列反应,得到两种两端均为活性基团的异端基遥爪聚乙二醇,这种方法具有普适性。通过1HNMR及GPC手段,表征了产物的结构、分子量及分子量分布。结果表明可以得到高产率、分子量可控且分布窄的异端基遥爪聚乙二醇。%Three hetero telechelic poly(ethylene glycol)s were obtained via anionic ring-opening polymerization of ethylene oxide using three new initiators :2-(benzyloxy)ethanol potassium、 2-(tetrahydro-2H-pyran-2-yloxy)ethanol potassium,2-allyloxyethanol potassium.The polymerization conditions were as follows:25 ℃,48 h,with equal ethanol and potassium naphthalene feeds.Using the polymerized product from 2-(benzyloxy)ethanol potassium as the start substance,two hetero telechelic poly(ethylene glycol)s with two functional end groups were synthesized through a series of reactions,the method was widely applicable to synthesizing hetero telechelic poly(ethylene glycol)s.The chemical structure,weight average molecular weight and distribution of the resultant products were characterized by 1H-NMR and GPC.The hetero telechelic poly(ethylene glycol)s that have high yields and controlled molecular weights and molecular weight distributions were obtained.

  17. Salvinorin A: allosteric interactions at the mu-opioid receptor.

    Science.gov (United States)

    Rothman, Richard B; Murphy, Daniel L; Xu, Heng; Godin, Jonathan A; Dersch, Christina M; Partilla, John S; Tidgewell, Kevin; Schmidt, Matthew; Prisinzano, Thomas E

    2007-02-01

    Salvinorin A [(2S,4aR,6aR,7R,9S,10aS,10bR)-9-(acetyloxy)-2-(3-furanyl)-dodecahydro-6a,10b-dimethyl-4,10-dioxo-2h-naphtho[2,1-c]pyran-7-carboxylic acid methyl ester] is a hallucinogenic kappa-opioid receptor agonist that lacks the usual basic nitrogen atom present in other known opioid ligands. Our first published studies indicated that Salvinorin A weakly inhibited mu-receptor binding, and subsequent experiments revealed that Salvinorin A partially inhibited mu-receptor binding. Therefore, we hypothesized that Salvinorin A allosterically modulates mu-receptor binding. To test this hypothesis, we used Chinese hamster ovary cells expressing the cloned human opioid receptor. Salvinorin A partially inhibited [(3)H]Tyr-D-Ala-Gly-N-Me-Phe-Gly-ol (DAMGO) (0.5, 2.0, and 8.0 nM) binding with E(MAX) values of 78.6, 72.1, and 45.7%, respectively, and EC(50) values of 955, 1124, and 4527 nM, respectively. Salvinorin A also partially inhibited [(3)H]diprenorphine (0.02, 0.1, and 0.5 nM) binding with E(MAX) values of 86.2, 64, and 33.6%, respectively, and EC(50) values of 1231, 866, and 3078 nM, respectively. Saturation binding studies with [(3)H]DAMGO showed that Salvinorin A (10 and 30 microM) decreased the mu-receptor B(max) and increased the K(d) in a dose-dependent nonlinear manner. Saturation binding studies with [(3)H]diprenorphine showed that Salvinorin A (10 and 40 microM) decreased the mu-receptor B(max) and increased the K(d) in a dose-dependent nonlinear manner. Similar findings were observed in rat brain with [(3)H]DAMGO. Kinetic experiments demonstrated that Salvinorin A altered the dissociation kinetics of both [(3)H]DAMGO and [(3)H]diprenorphine binding to mu receptors. Furthermore, Salvinorin A acted as an uncompetitive inhibitor of DAMGO-stimulated guanosine 5'-O-(3-[(35)S]thio)-triphosphate binding. Viewed collectively, these data support the hypothesis that Salvinorin A allosterically modulates the mu-opioid receptor.

  18. Inhibiting heat-shock protein 90 reverses sensory hypoalgesia in diabetic mice

    Directory of Open Access Journals (Sweden)

    Brian S J Blagg

    2010-08-01

    Full Text Available Increasing the expression of Hsp70 (heat-shock protein 70 can inhibit sensory neuron degeneration after axotomy. Since the onset of DPN (diabetic peripheral neuropathy is associated with the gradual decline of sensory neuron function, we evaluated whether increasing Hsp70 was sufficient to improve several indices of neuronal function. Hsp90 is the master regulator of the heat-shock response and its inhibition can up-regulate Hsp70. KU-32 (N-{7-[(2R,3R,4S,5R-3,4-dihydroxy-5-methoxy-6,6-dimethyl-tetrahydro-2H-pyran-2-yloxy]-8-methyl-2-oxo-2H-chromen-3-yl}acetamide was developed as a novel, novobiocin-based, C-terminal inhibitor of Hsp90 whose ability to increase Hsp70 expression is linked to the presence of an acetamide substitution of the prenylated benzamide moiety of novobiocin. KU-32 protected against glucose-induced death of embryonic DRG (dorsal root ganglia neurons cultured for 3 days in vitro. Similarly, KU-32 significantly decreased neuregulin 1-induced degeneration of myelinated Schwann cell DRG neuron co-cultures prepared from WT (wild-type mice. This protection was lost if the co-cultures were prepared from Hsp70.1 and Hsp70.3 KO (knockout mice. KU-32 is readily bioavailable and was administered once a week for 6 weeks at a dose of 20 mg/kg to WT and Hsp70 KO mice that had been rendered diabetic with streptozotocin for 12 weeks. After 12 weeks of diabetes, both WT and Hsp70 KO mice developed deficits in NCV (nerve conduction velocity and a sensory hypoalgesia. Although KU-32 did not improve glucose levels, HbA1c (glycated haemoglobin or insulin levels, it reversed the NCV and sensory deficits in WT but not Hsp70 KO mice. These studies provide the first evidence that targeting molecular chaperones reverses the sensory hypoalgesia associated with DPN.

  19. Induction of heat shock protein 70 (Hsp70 prevents neuregulin-induced demyelination by enhancing the proteasomal clearance of c-Jun

    Directory of Open Access Journals (Sweden)

    Rick T Dobrowsky

    2012-12-01

    Full Text Available Modulating molecular chaperones is emerging as an attractive approach to treat neurodegenerative diseases associated with protein aggregation, DPN (diabetic peripheral neuropathy and possibly, demyelinating neuropathies. KU-32 [N-(7-((2R,3R,4S,5R-3,4-dihydroxy-5-methoxy-6,6-dimethyl-tetrahydro-2H-pyran-2-yloxy-8-methyl-2-oxo-2H-chromen-3-ylacetamide] is a small molecule inhibitor of Hsp90 (heat shock protein 90 and reverses sensory deficits associated with myelinated fibre dysfunction in DPN. Additionally, KU-32 prevented the loss of myelinated internodes induced by treating myelinated SC (Schwann cell-DRG (dorsal root ganglia sensory neuron co-cultures with NRG1 (neuregulin-1 Type 1. Since KU-32 decreased NRG1-induced demyelination in an Hsp70-dependent manner, the goal of the current study was to clarify how Hsp70 may be mechanistically linked to preventing demyelination. The activation of p42/p44 MAPK (mitogen-activated protein kinase and induction of the transcription factor c-Jun serve as negative regulators of myelination. NRG1 activated MAPK, induced c-Jun expression and promoted a loss of myelin segments in DRG explants isolated from both WT (wild-type and Hsp70 KO (knockout mice. Although KU-32 did not block the activation of MAPK, it blocked c-Jun induction and protected against a loss of myelinated segments in WT mice. In contrast, KU-32 did not prevent the NRG1-dependent induction of c-Jun and loss of myelin segments in explants from Hsp70 KO mice. Overexpression of Hsp70 in myelinated DRG explants prepared from WT or Hsp70 KO mice was sufficient to block the induction of c-Jun and the loss of myelin segments induced by NRG1. Lastly, inhibiting the proteasome prevented KU-32 from decreasing c-Jun levels. Collectively, these data support that Hsp70 induction is sufficient to prevent NRG1-induced demyelination by enhancing the proteasomal degradation of c-Jun.

  20. Inhibiting heat-shock protein 90 reverses sensory hypoalgesia in diabetic mice.

    Science.gov (United States)

    Urban, Michael J; Li, Chengyuan; Yu, Cuijuan; Lu, Yuanming; Krise, Joanna M; McIntosh, Michelle P; Rajewski, Roger A; Blagg, Brian S J; Dobrowsky, Rick T

    2010-08-11

    Increasing the expression of Hsp70 (heat-shock protein 70) can inhibit sensory neuron degeneration after axotomy. Since the onset of DPN (diabetic peripheral neuropathy) is associated with the gradual decline of sensory neuron function, we evaluated whether increasing Hsp70 was sufficient to improve several indices of neuronal function. Hsp90 is the master regulator of the heat-shock response and its inhibition can up-regulate Hsp70. KU-32 (N-{7-[(2R,3R,4S,5R)-3,4-dihydroxy-5-methoxy-6,6-dimethyl-tetrahydro-2H-pyran-2-yloxy]-8-methyl-2-oxo-2H-chromen-3-yl}acetamide) was developed as a novel, novobiocin-based, C-terminal inhibitor of Hsp90 whose ability to increase Hsp70 expression is linked to the presence of an acetamide substitution of the prenylated benzamide moiety of novobiocin. KU-32 protected against glucose-induced death of embryonic DRG (dorsal root ganglia) neurons cultured for 3 days in vitro. Similarly, KU-32 significantly decreased neuregulin 1-induced degeneration of myelinated Schwann cell DRG neuron co-cultures prepared from WT (wild-type) mice. This protection was lost if the co-cultures were prepared from Hsp70.1 and Hsp70.3 KO (knockout) mice. KU-32 is readily bioavailable and was administered once a week for 6 weeks at a dose of 20 mg/kg to WT and Hsp70 KO mice that had been rendered diabetic with streptozotocin for 12 weeks. After 12 weeks of diabetes, both WT and Hsp70 KO mice developed deficits in NCV (nerve conduction velocity) and a sensory hypoalgesia. Although KU-32 did not improve glucose levels, HbA1c (glycated haemoglobin) or insulin levels, it reversed the NCV and sensory deficits in WT but not Hsp70 KO mice. These studies provide the first evidence that targeting molecular chaperones reverses the sensory hypoalgesia associated with DPN.

  1. Induction of heat shock protein 70 (Hsp70) prevents neuregulin-induced demyelination by enhancing the proteasomal clearance of c-Jun.

    Science.gov (United States)

    Li, Chengyuan; Ma, Jiacheng; Zhao, Huiping; Blagg, Brian S J; Dobrowsky, Rick T

    2012-12-06

    Modulating molecular chaperones is emerging as an attractive approach to treat neurodegenerative diseases associated with protein aggregation, DPN (diabetic peripheral neuropathy) and possibly, demyelinating neuropathies. KU-32 [N-(7-((2R,3R,4S,5R)-3,4-dihydroxy-5-methoxy-6,6-dimethyl-tetrahydro-2H-pyran-2-yloxy)-8-methyl-2-oxo-2H-chromen-3-yl)acetamide] is a small molecule inhibitor of Hsp90 (heat shock protein 90) and reverses sensory deficits associated with myelinated fibre dysfunction in DPN. Additionally, KU-32 prevented the loss of myelinated internodes induced by treating myelinated SC (Schwann cell)-DRG (dorsal root ganglia) sensory neuron co-cultures with NRG1 (neuregulin-1 Type 1). Since KU-32 decreased NRG1-induced demyelination in an Hsp70-dependent manner, the goal of the current study was to clarify how Hsp70 may be mechanistically linked to preventing demyelination. The activation of p42/p44 MAPK (mitogen-activated protein kinase) and induction of the transcription factor c-Jun serve as negative regulators of myelination. NRG1 activated MAPK, induced c-Jun expression and promoted a loss of myelin segments in DRG explants isolated from both WT (wild-type) and Hsp70 KO (knockout) mice. Although KU-32 did not block the activation of MAPK, it blocked c-Jun induction and protected against a loss of myelinated segments in WT mice. In contrast, KU-32 did not prevent the NRG1-dependent induction of c-Jun and loss of myelin segments in explants from Hsp70 KO mice. Overexpression of Hsp70 in myelinated DRG explants prepared from WT or Hsp70 KO mice was sufficient to block the induction of c-Jun and the loss of myelin segments induced by NRG1. Lastly, inhibiting the proteasome prevented KU-32 from decreasing c-Jun levels. Collectively, these data support that Hsp70 induction is sufficient to prevent NRG1-induced demyelination by enhancing the proteasomal degradation of c-Jun.

  2. Quantitative determination of sotolon, maltol and free furaneol in wine by solid-phase extraction and gas chromatography-ion-trap mass spectrometry.

    Science.gov (United States)

    Ferreira, Vicente; Jarauta, Idoia; López, Ricardo; Cacho, Juan

    2003-08-22

    A method for the analytical determination of sotolon [4,5-dimethyl-3-hydroxy-2(5H)-furanone], maltol [3-hydroxy-2-methyl-4H-pyran-4-one] and free furaneol [2,5-dimethyl-4-hydroxy-3(2H)-furanone] in wine has been developed. The analytes are extracted from 50 ml of wine in a solid-phase extraction cartridge filled with 800 mg of LiChrolut EN resins. Interferences are removed with 15 ml of a pentane-dichloromethane (20:1) solution, and analytes are recovered with 6 ml of dichloromethane. The extract is concentrated up to 0.1 ml and analyzed by GC-ion trap MS. Maltol and sotolon were determined by selected ion storage of ions in the m/z ranges 120-153 and 79-95, using the ions m/z 126 and 83 for quantitation, respectively. Furaneol was determined by non-resonant fragmentation of the m/z 128 mother ion and subsequent analysis of the m/z 81 ion. The detection limits of the method are in all cases between 0.5 and 1 microg l(-1), well below the olfactory thresholds of the compounds. The precision of the method is in the 4-5% range for levels in wine around 20 microg l(-1). Linearity holds at least up to 400 microg l(-1), and is satisfactory in all cases. The recoveries of maltol and sotolon are constant (70 and 64%, respectively) and do not depend on the type of wine. On the contrary, in the case of furaneol, red wines show constant and high recoveries (97%), while the recoveries on white wines range between 30 and 80%. Different experiments showed that this behavior is probably due to the existence of complexes formed between furaneol and sulphur dioxide or catechols. Sensory experiments confirmed that the complexed forms found in white wines are not perceived by orthonasal olfaction, and that the furaneol determined by the method can be considered as the free and odor-active fraction.

  3. Oxidation Control and Odors Analysis of Lard by GC-MS%猪脂控制氧化及其香气成分GC—MS分析

    Institute of Scientific and Technical Information of China (English)

    刘丽微; 白卫东; 赵文红; 钱敏; 刘朝霞

    2011-01-01

    Peroxide value (POV), acid value (AV) and p-anisidine value (P-AV)are the indexes of oxidation state of lard. The optimal conditions for controlling oxidation are oxidized at 130 ℃ for 4 h. The results shows that the peroxide value is 341 meq/kg, the acid value is 1.40 mgKOH/g and p-anisidine value is 580. The volatile compounds are extracted by solid-phase micro-extraction (SPME) and analyzed by gas chromatography-mass spectrometry (GC-MS). Eighty five sapid compounds are detected, including 20 aldehydes which account for 53.34% of total aroma compounds (E, E) - 2,4-Decadienal was 27.03% , the highest content of the whole components. In addition, ketones, alcohols, olefin, furan, pyran, pyridine, 8- Nonalaetone, γ- Dodecalactone, and other sapid substances are detected as well.%文中以过氧化值(POV)、酸值(AV)、茴香胺值(P—AV)表征猪脂氧化状态,并确定生产优质猪肉味香精的脂肪控制氧化条件为:温度130℃,时间4h,此时油脂的过氧化值为341meq/kg、酸值为1.4mgKOH/g、茴香胺值为580。通过固相微萃取法(SPME)萃取油脂挥发性成分,气-质联用(GC-MS)分析猪脂控制氧化前后的产物,试验共检测出85种呈味物质,其中醛类物质20种,含量占香气成分总量的53.34%,(E,E)-2,4-癸二烯醛含量最高达到27.03%。此外还检测到酮类、醇类、烃类、呋喃、吡喃、吡啶类、6-戊丁基内酯、γ-十二内酯等多种呈味物质。

  4. 胡萝卜果胶的化学结构特征研究与含量测定%Chemical Structure and Content Determination of Carrot Pectin

    Institute of Scientific and Technical Information of China (English)

    李洋; 何立巍; 何睦; 李晓曦; 彭稳稳; 笪婧雯; 耿婷婷; 武圆圆

    2012-01-01

    OBJECTIVE: To study the chemical structure of carrot pectin and to determine the content of it. METHODS: The average molecular weight was determinate by HPGPC; Paper chromatography (PC) and HPLC were used to identify the major monosaccharide component of pectin; UV and IR spectroscopy indentiry the chemical structure; the content of pectin was determined by sulfuric acid-cardyl method. RESULTS: The average molecular weight of carrot pectin was 1 750 625 and monosaccharide mainly composed of D-galactolipin and D-galacturonic acid; monosaccharide was mainly connected by β-pyran type glycosidic bonds. The content of pectin to galacturonic acid was 66.06%. CONCLUSION: The carrot pectin extract has large content of poly-saccharide and obvious chemical structure. The trial provides theory and trial basis for further development of carrot pectin.%目的:研究胡萝卜果胶的化学结构特征,并测定其含量.方法:采用高效凝胶渗透液相色谱法测定胡萝卜果胶的相对分子质量;纸色谱、高效液相色谱法鉴别果胶中主要单糖组成;紫外、红外光谱法鉴别其化学结构特征;硫酸-咔唑法测定果胶的含量.结果:胡萝卜果胶的平均相对分子质量为1750625,主要单糖组成为D-半乳糖和D-半乳糖醛酸;单糖的连接方式主要为β-吡喃型糖苷键连接.果胶含量以半乳糖醛酸计为66.06%.结论:胡萝卜果胶提取物多糖含量较高、化学结构特征明显.本试验结果可为胡萝卜果胶的进一步开发提供理论和试验基础.

  5. Biochemical fingerprint and pharmacological applications of Barleria noctiflora L.f. leaves.

    Science.gov (United States)

    Alagar Yadav, Sangilimuthu; Ramalingam, Sathishkumar; Jebamalairaj, Anitha; Subban, Ravi; Sundaram, Karpagavalli Mennakshi

    2016-12-01

    Background Antioxidant and antihistamine agents from Barleria noctiflora L.f. as natural source due to the existing modern medicine give various adverse effects to overcome these problems with natural products. MethodsB. noctiflora leaves extract was fractionated with column chromatography; the homogenized fractions were monitored with thin layer chromatography (TLC) and characterized by using UV-visible, FT-IR, 1H NMR, 13C NMR and mass spectrometry spectral studies. The volatile phytoconstituents of B. noctiflora extract were analysed by gas chromatography-mass spectrometry. Phytoconstituents from B. noctiflora leaves extract were screened for their antioxidant and antihistamine potential in vitro (2,2-diphenyl-1-picrylhydrazyl radical scavenging activity, 2,2'-azinobis-3-ethylbenzothiozoline-6-sulfonic acid radical decolouration assay, nitric oxide radical scavenging activity, superoxide radical scavenging activity and hydrogen peroxide radical scavenging activity) and in silico (molecular docking), respectively. Results Antioxidant and antihistamine barlerinoside has been isolated and characterized from the leaves of B. noctiflora L.f. Barlerinoside revealed their free-radical scavenging ability on OH-, OH•, NO-, O2- and H2O2 radicals and found high percentage inhibition against OH- radical at the IC50 value of 50.45±2.52  µg. The methanol (MeOH) extract of B. noctiflora leaves contains cyclotene; N,N-dimethylglycine; tetrahydrocyclopenta [1,3] dioxin-4-one; phenol, 2-methoxy-; benzofuran, 2-methyl-; 1,4:3,6-dianhydro-α-d-glucopyranose; 2-methoxy-4-vinylphenol; 1,3;2,5-dimethylene-l-rhamnitol; levoglucosan and bicyclo[2.2.2]oct-7-ene-2,5-dione as being the major compounds. Among phytoconstituents present in the extract, the hexestrol; 1,2-benzenedicarboxylic acid, bis(2-methylpropyl) ester; 1-(3,6,6-trimethyl-1,6,7,7a-tetrahydrocyclopenta[c]pyran-1-yl) ethanone; megastigmatrienone; furan interacted with histamine H1 receptor and bind at GLU-177 and ASP

  6. Triplet-triplet annihilation process in organic light-emitting diodes doped with fluorescent dyes%三重态激子在不同荧光染料掺杂体系中的湮灭过程

    Institute of Scientific and Technical Information of China (English)

    阚敏; 陈平; 曹绍谦; 刘文利; 宋群梁; 熊祖洪

    2010-01-01

    室温下,在红色荧光染料掺杂的有机发光器件ITO/N,N'-bis(naphthalen-1-y)-N,N'-bis(phenyl)benzidine (NPB)/tris(8-hydroxyquinolato) aluminum (Alq3):4-dicyanomethylene-2-methyl-6-p-dimethylaminostyryl-4H-pyran(DCM),Alq3/LiF/A1中,观察到发光随外磁场的变化(即磁致发光)表现为刚开始的快速增加,在~50 mT处达到最大后,随着磁场的进一步增加,又呈现出减弱的特点(即高场效应);而且,器件的掺杂浓度越高、所加偏压越大,该高场减弱就越明显.但在另一类绿色荧光染料5,12-dihydro-5,12-dimethylquino [2,3-b]acridine-7,14-dione (DMQA)的掺杂器件中,磁致发光的高场部分则是在~50 mT后增加变缓并逐渐趋于饱和.分析结果表明,F(o)rster能量转移过程占主导发射的DMQA掺杂器件,不利于染料分子上三重态激子的形成,从而,通过三重态激子对(triplet pairs)湮灭产生单重态激子(triplet-triplet annihilation,TTA)的过程不易发生;但在载流子陷阱效应参与发射的DCM掺杂器件中,室温下在染料分子上就可以形成寿命较长的三重态激子,增加了发生TTA过程的几率.因此,基于掺杂器件中两种不同的发射机制,外加磁场对有机发光中三重态激子对(T…T)的演化表现出了不同的调控作用.

  7. 淀粉水解糖与谷氨酸反应物的制备与分析%Preparation and Analysis of Product From Reaction Between the Hydrolysate of the Sugar and Glutamic Acid

    Institute of Scientific and Technical Information of China (English)

    宋文东; 周靖; 邵艳秋; 刘倩

    2001-01-01

    This paper reported that 5 h reaction between hydrolysate of the sugar (200 g) and glutamic acid (8 0 g,pH=7) at 95~105 ℃ produced a sticky brown product. The ether-soluable compounds of the reaction products from the hy drolysate of the sugar and glutamic acid has been analyzed with GC-MS. The chart s of the mass spec trum was verified by NIST62LIB and NIST12LIB spectrum library index c ombinding with EPA/NIH standard mass spectrum. Unification of the whole iron fl ow has been accepted as quantitative method. The analysis result shows that this condensation product has 21 contants. Five of them are Furans and Pyrans, which are respectively. The above five contants share 60.13%, and their most common charateristic fragr ance is caramel dece at which can be used to color cigarate and fruit and make them fragrant.%报道了用淀粉水解糖与谷氨酸在pH=7,温度95~105 ℃下反应5 h, 得到粘稠状棕色反应物 。用气相色谱-质谱(GC-MS)对其醚溶性产物进行分析。质谱图的确认采用NIST62LIB及N IST12LIB谱库检索及EPA/NIH质谱标准图相结合。定量采用总离子流各峰面积归一化。分析 结果表明:此种缩合产物为21个组分,其中吡喃、呋喃类化合物占5种,其含量占总量的60.13%。香气特征为焦糖香,可用于烟草及食品的着色致香。

  8. 红豆杉多糖的提取与结构初探%Extraction of Maire Yew Polysaccharide and Its Structure

    Institute of Scientific and Technical Information of China (English)

    郑德勇; 徐莉; 郑月梅; 林清霞

    2012-01-01

    A polysaccharide was prepared from the branches and leaves of the Taxus ckinensis var. mairei by the processing of hot water extraction, concentration, alcohol-precipitation, dialysis and protein isolation successively. The polysaccharide molecular weight was determined by Sephadex G-100 gel permeation chromatography. The monosaccharide composition of the taxus polysaccharide was determined by gas chromatography. And IR spectra of taxus polysaccharide were determined, too. The results showed that the taxus polysaccharide' s molecular weight was 59. 2 ku, which composed of 365 monosaccharide groups. The ratio of Rhamnose, Arabinose, Mannose, Glucose and Galactose was 4:6:1:1:4. The taxus polysaccharide was a glycoconjugate that composed of several kinds of monosaccharide, glucuronic acid and amino acid. The monosaccharide was in the form of pyran ring and linked by β-( 1,3) glucosidic bond each other. The peptide in taxus polysaccharide couldn't be destructed by Sevag method.%红豆杉枝叶经热水浸提、浓缩、醇沉、透析等工序制得一种红豆杉多糖,采用Sephadex G-100凝胶渗透法测定分子质量,采用气相色谱法测定其单糖组成,并测定了不同纯度红豆杉多糖的红外光谱.所得红豆杉多糖分子质量约为59.2ku,可视为由约365个糖残基构成的高分子化合物,其单糖残基鼠李糖、阿拉伯糖、甘露糖、葡萄糖、半乳糖数量比约为4∶6∶1∶1∶4.该红豆杉多糖分子结构中含有普通单糖、糖醛酸或氨基酸残基等,单糖主要以吡喃环形式存在、通过β-(1,3)苷键结合形成一种糖蛋白缀合物,Sevag法处理不能完全除去分子中的肽链.

  9. Isolation, Cultivation of a Sponge-Derived Fungus and Studes on Its Bioactive Metabolites%海绵微生物的分离培养及一种活性代谢产物的初步研究

    Institute of Scientific and Technical Information of China (English)

    方玉春; 李凌绪; 朱天骄; 蔡生新; 顾谦群; 朱伟明; 王长云; 郝双红

    2009-01-01

    研究海绵来源真菌Aspergillus repens发酵产物中的活性代谢产物.分离培养微生物进行活性筛选,采用活性追踪的方法、利用色谱手段分离获得单体化合物,根据波谱分析及其理化性质确定其结构,利用SRB评价单体化合物的抗肿瘤活性,利用纸片法测定单体化合物的抗植物病菌活性.获得1个萘并吡喃酮化合物,其结构鉴定为3,4-二氢-9,10-二羟基-7-甲氧基-3-甲基-1H-萘并[2,3c]吡喃-1-酮 (Semivioxanthin).该化合物对肿瘤细胞A-549、HL-60和BEL-7402有一定抑制作用,对植物致病菌作用较强.海绵微生物代谢产物是发现活性物质重要资源,值得深入研究.%To investigate the bioactive metabolites of sponge-derived fungus Aspergillus repens. Sponge-derived fungi were isolated and cultivated. The bioactive compounds were isolated by bioassay-guided separation procedure and their structures were identified by means of spectral analysis and physicochemical properties. Their bioactivities were preliminarily evaluated in vitro by the SRB and paper method. An anthraquinone was isolated and its structure was identified as 3,4-Dihydro-9,10-dihydroxy-7-methoxy-3-methyl-1H-naptho [2,3c] pyran-1-one. The anthraquinone showed moderate cytotoxicity against A-549, HL-60, BEL-7402 and strong fungicidal activity against plant pathogen. Sponge-derived fungi are important resources for drug discovery.

  10. Amaranthus roxburghianus root extract in combination with piperine as a potential treatment of ulcerative colitis in mice

    Institute of Scientific and Technical Information of China (English)

    Sunil A.Nirmal; Jayashri M.Ingale; Shashikant R.Pattan; Sanjay B.Bhawar

    2013-01-01

    OBJECITVE:The present work was undertaken to determine the effects of Amaranthus roxburghianus Nevski.(Amaranthaceae) root alone and in combination with piperine in treating ulcerative colitis (UC) in mice.METHODS:Swiss albino mice were divided into seven groups (n =6).Standard group received prednisolone (5 mg/kg,intraperitoneally).Treatment groups received hydroalcoholic extract of roots of A.roxburghianus (50 and 100 mg/kg,per oral) and a combination of hydroalcoholic extract of roots of A.roxburghianus (50 and 100 mg/kg,per oral) and piperine (5 mg/kg,per oral).Ulcer index,colitis severity,myeloperoxidase (MPO),malondialdehyde and glutathione were estimated from blood and tissue.Column chromatography of the extract was done and purified fractions were analyzed by gas chromatography-mass spectroscopy (GC-MS).RESULTS:Treatment with the combination of hydroalcoholic extract of A.roxburghianus and piperine showed minimal ulceration,hemorrhage,necrosis and leucocyte infiltration by histopathological observation.Acetic acid increased MPO levels in blood and colon tissue to 355 U/mL and 385 U/mg,respectively.The combination of hydroalcoholic extract of A.roxburghianus (100 mg/kg) and piperine (5 mg/kg) significantly decreased MPO in blood and tissue to 182 U/mL and 193 U/mg,respectively (P < 0.05).Similarly,this combination significantly reduced malondialdehyde levels and increased glutathione levels in blood and tissue.Various phytoconstituents were detected by GC-MS.CONCLUSION:The combination of hydroalcoholic extract of A.roxburghianus and piperine is effective in the treatment of UC and the effects are comparable with the standard drug prednisolone.4H-pyran-4-one,2,3-dihydro-3,5-dihydroxy-6-methyl,eugenol and benzene,and 1-(1,5-dimethyl-4-hexenyl)-4-methyl are reported having analgesic,anti-inflammatory,and antioxidant properties; they may play a role in the biological activity of A.roxburghianus root.

  11. Bioactive Secondary Metabolites Produced by the Oak Pathogen Diplodia corticola.

    Science.gov (United States)

    Masi, Marco; Maddau, Lucia; Linaldeddu, Benedetto Teodoro; Cimmino, Alessio; D'Amico, Wanda; Scanu, Bruno; Evidente, Marco; Tuzi, Angela; Evidente, Antonio

    2016-01-13

    Three new lactones and a new fatty acid ester, named sapinofuranones C and D, diplopyrone B, and diplobifuranylone C, respectively, were isolated from Diplodia corticola, together with sphaeropsidins A and C, diplopyrone, diplobifuranylones A and B, diplofuranone A, and the (S,S)-enantiomer of sapinofuranone B. Sapinofuranones C and D, diplopyrone B, and diplobifuranylone C were characterized as (5S)-5-((1,S-1,6-dihydroxyhexa-2,4-dienyl)-dihydrofuran-2-one, 4,5-dihydroxy-deca-6,8-dienoic acid methyl ester, (5S)-5-hydroxy-6-(penta-1,3-dienyl)-5,6-dihydro-pyran-2-one, and 5'-((1R)-1-hydroxyethyl)-2',5'-dihydro-2H-[2,2']bifuranyl-5-one by spectroscopic and chemical methods, respectively. The relative configuration of sapinofuranone C was assigned by X-ray diffraction analysis, whereas its absolute configuration was determined by applying the advanced Mosher's method to its 11-O-p-bromobenzoyl derivative. The same method was used to assign the absolute configuration to C-5 of diplopyrone B and to that of the hydroxyethyl of the side chain of diplobifuranylone C, respectively. The metabolites isolated were tested at 1 mg/mL on leaves of cork oak, grapevine cv. 'Cannonau', and tomato using the leaf puncture assay. They were also tested on tomato cuttings at 0.2, 0.1, and 0.05 mg/mL. Each compound was tested for zootoxic activity on Artemia salina L. larvae. The efficacy of sapinofuranone C and diplopyrone B on three plant pathogens, namely, Athelia rolfsii, Fusarium avenaceum, and Phytophthora nicotianae was also evaluated. In all phytotoxic assays only diplopyrone B was found to be active. It also showed strong inhibition on the vegetative growth of A. rolfsii and P. nicotianae. All metabolites were inactive in the assay performed for the zootoxic activity (A. salina) even at the highest concentration used (200 μg/mL). Diplopyrone B showed a promising antioomycete activity for the control of Phytophthora spp. also taking into account the absence of zootoxic activity.

  12. Organic light emitting devices with doped electron transport and hole blocking layers

    Energy Technology Data Exchange (ETDEWEB)

    Tardy, J. [Laboratoire d' Electronique, Optoelectronique et Microsystemes (LEOM, UMR CNRS no 5512) Ecole Centrale de Lyon, 36 avenue Guy de Collongue, 69134 Ecully Cedex (France)]. E-mail: jacques.tardy@ec-lyon.fr; Khalifa, M. Ben [Laboratoire d' Electronique, Optoelectronique et Microsystemes (LEOM, UMR CNRS no 5512) Ecole Centrale de Lyon, 36 avenue Guy de Collongue, 69134 Ecully Cedex (France); Vaufrey, D. [Laboratoire d' Electronique, Optoelectronique et Microsystemes (LEOM, UMR CNRS no 5512) Ecole Centrale de Lyon, 36 avenue Guy de Collongue, 69134 Ecully Cedex (France)

    2006-03-15

    This study reports on heterostructure OLEDs with n-type molecularly doped electron transport layer and hole blocking layer. The influence of doping on the operating voltage and on light emission performances was investigated. The n-type doping molecule is 2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (PBD) dispersed into either an 8-(hydroquinoline) aluminum (Alq) electron transport layer (ETL) or a 2,9-Dimethyl-4,7-diphenyl-1,10-phenanthroline (Bathocuproine BCP) hole blocking layer (HBL). The typical device structure is glass substrate/indium tin oxide/PEDOT/TPD-F4-TCNQ/Alq-DCM/BCP/Alq/Mg-Ag where Poly(3,4)ethylenedioxythiophene/Polystyrenesulphonate (PEDOT/PSS) is a hole injecting layer, TPD-F4-TCNQ is a hole transport layer (HTL) made of N,N'-Bis(3-methylphenyl)-N,N'-diphenylbenzidine (TPD) doped with 2 wt.% of 2,3,5,6-tetrafluoro-7,7,8,8-tetracyano-quinodimethane (F4-TCNQ) and Alq-DCM is the emitting layer (EML) made of Alq doped with 2 wt.% of 4-dicyanomethylene-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran (DCM) orange dye. The modified cathode consists in a combination of a BCP HBL and an Alq ETL where BCP or/and Alq were doped with PBD. Lowest operating voltage (3 V for a luminance of 10 Cd/m{sup 2}) and brightest devices (6000 Cd/m{sup 2}) were obtained with a hole blocking bilayer made of BCP doped with 28 wt.% deposited onto an undoped BCP (each one being 5 nm thick). Adding an undoped Alq layer improved the device current efficiency (4 Cd/A) but is detrimental to the operating voltage (6 V for a luminance of 10 Cd/m{sup 2}). In the absence of real n-type doping with organic molecules, our results point out that the design of molecular doped injection layer at the cathode will need for a compromise between high luminance and efficiency on one hand and low operating voltage on the other hand.

  13. A novel V(IV)O-pyrimidinone complex: synthesis, solution speciation and human serum protein binding.

    Science.gov (United States)

    Gonçalves, Gisela; Tomaz, Isabel; Correia, Isabel; Veiros, Luís F; Castro, M Margarida C A; Avecilla, Fernando; Palacio, Lorena; Maestro, Miguel; Kiss, Tamás; Jakusch, Tamás; Garcia, M Helena V; Pessoa, João Costa

    2013-09-07

    The pyrimidinones mhcpe, 2-methyl-3H-5-hydroxy-6-carboxy-4-pyrimidinone ethyl ester (mhcpe, 1), 2,3-dimethyl-5-benzyloxy-6-carboxy-4-pyrimidinone ethyl ester (dbcpe, 2) and N-methyl-2,3-dimethyl-5-hydroxy-6-carboxyamido-4-pyrimidinone (N-MeHOPY, 3), are synthesized and their structures determined by single crystal X-ray diffraction. The acid-base properties of 1 are studied by potentiometric and spectrophotometric methods, the pK(a) values being 1.14 and 6.35. DFT calculations were carried out to determine the most stable structure for each of the H2L(+), HL and L(-) forms (HL = mhcpe) and assign the groups involved in the protonation-deprotonation processes. The mhcpe(-) ligand forms stable complexes with V(IV)O(2+) in the pH range 2 to 10, and potentiometry, EPR and UV-Vis techniques are used to identify and characterize the V(IV)O-mhcpe species formed. The results are consistent with the formation of V(IV)O, (V(IV)O)L, (V(IV)O)L2, (V(IV)O)2L2H(-2), (V(IV)O)L2H(-1), (V(IV)O)2L2H(-3), (V(IV)O)LH(-2) species and V(IV)O-hydrolysis products. Calculations indicate that the global binding ability of mhcpe towards V(IV)O(2+) is similar to that of maltol (Hmaltol = 3-hydroxy-2-methyl-4H-pyran-4-one) and lower than that of 1,2-dimethyl-3-hydroxy-4-pyridinone (Hdhp). The interaction of V(IV)O-complexes with human plasma proteins (transferrin and albumin) is studied by circular dichroism (CD), EPR and (51)V NMR spectroscopy. V(IV)O-mhcpe-protein ternary complexes are formed in both cases. The binding of V(IV)O(2+) to transferrin (hTF) in the presence of mhcpe involves mainly (V(IV)O)1(hTF)(mhcpe)1, (V(IV)O)2(hTF)(mhcpe)1 and (V(IV)O)2(hTF)(mhcpe)2 species, bound at the Fe(III) binding sites, and the corresponding conditional formation constants are determined. Under the conditions expected to prevail in human blood serum, CD data indicate that the V(IV)O-mhcpe complexes mainly bind to hTF; the formation of V(IV)O-hTF-mhcpe complexes occurs in the presence of Fe(III) as well

  14. Anti-inflammatory properties of dietary flavonoids Propiedades antiinflamatorias de los flavonoides de la dieta

    Directory of Open Access Journals (Sweden)

    J. González-Gallego

    2007-06-01

    Full Text Available Flavonoids are a group of natural substances that are located in sources of vegetal origin. More than 4,000 varieties of flavonoids have been identified. All of them are phenyl-benzopyrones of low molecular weight with a basic structure formed by two benzene rings united through a heterocyclic pyrane or pyrone. Besides their relevance in plants, flavonoids are important for human health. Their antioxidant capacity confers a therapeutic potential in cardiovascular diseases, gastric or duodenal ulcers, cancer or hepatic pathologies. Also important are their antiviral and anti-allergic actions, as well as their anti-thrombotic and anti-inflammatory properties. Prostaglandins and nitric oxide biosynthesis is involved in inflammation, and isoforms of inducible nitric oxide synthase (iNOS and of cyclooxygenase (COX-2 are responsible for the production of a great amount of these mediators. It has been demonstrated that flavonoids are able to inhibit both enzymes, as well as other mediators of the inflammatory process such as reactive C protein or adhesion molecules. Modulation of the cascade of molecular events leading to the overexpression of those mediators include inhibition of transcription factors such as nuclear factor kappa B and AP-1, through the inhibition of protein kinases involved in signal transduction. Increased antioxidant defenses through activation of the NF-E2 related factor 2 (Nrf2 also contribute to the anti-inflammatory capacity of flavonoidsLos flavonoides son un grupo de las sustancias naturales que se encuentran en fuentes de origen vegetal, existiendo más de 4.000 variedades. Todos son fenilbenzopironas de peso molecular bajo con una estructura básica formada por dos anillos heterocíclicos de benceno unidos a través de un pirano o de una pirona. Además de su función en las plantas, los flavonoides son importantes para la salud humana. Su capacidad antioxidante confiere un potencial terapéutico en enfermedades

  15. Building three-dimensional structures of HIV-1 coreceptor CCR5 and its interaction with antagonist TAK779 by comparative molecular modeling%HIV-共受体CCR5的三维结构及与其拮抗剂TAK 779相互作用的比较分子模拟

    Institute of Scientific and Technical Information of China (English)

    黄小琴; 蒋华良; 罗小民; 陈凯先; 嵇汝运; 曹阳; 裴钢

    2000-01-01

    AIM: To study the mechanism of interaction of CCR5receptor with its antagonist TAK779. METHODS:Comparative molecular modeling has been used to develop the 3D-structural models of CCR5 receptor and its complex with TAK779. Molecular mechanics has been applied to optimize the above molecular models. Quantum mechanics has been utilized to calculate the structural information of TAK779. DOCK4.0 program is employed to dock the TAK779 molecular into the binding site of CCR5 receptor. RESULTS: The 3D-structural model of CCR5 receptor is constructed using the 3D-model of frog rhodopsin as a template. The binding pocket is situated in the transmembrane helices 3, 5, 6, and 7,and it is composed of conserved residues of Tyrl08,Glylll, Serll4, Glu283, Gly286, and Cys290, and conservatively varied residues including Thrl05, Leul07,Phell2, Glyll5, Lys197, and Met287. O1, N7, N17,and O19 of TAK779 are the active center of TAK779.The pyran cycle and the aminium group of TAK779 interact with residues in the binding pocket of CCR5 receptor,the other part of TAK779 interacts with residues from the extracellular loops of CCR5. The binding energy of TAK779 with CCR5 is - 51. 606 kcal/mol. CONCLUSION: The model constructed and the interaction mode reported in the present study are useful in further understanding the molecular mechanism of receptor-virus%目的:研究HⅣ-1的共受体CCR5与其拮抗剂TAK779的相互作用机制。方法:用比较分子模拟方法建立CCR5受体的三维结构模型;通过量子化学计算得到TAK779分子的结构参数和最优几何构型;用DOCK4.0程序将TAK779分子对接到CCR5受体的结合位点上。结果:通过分子力学优化得到了CCR5受体的三维结构模型,配体的结合口袋位于第三、五、六、七跨膜区,组成结合口袋的氨基酸残基主要为 Thr105、Leu107、Tyr108、Gly111、Phe112、Ser114、Cly115、Lys197、Glu283、Gly286、Met287、Cys290;TAK779与CCR5受体的相互作用方式

  16. Patulin: incidence and control in apple products / Patulina: incidência e controle em derivados de maçã

    Directory of Open Access Journals (Sweden)

    Crispin Humberto Garcia-Cruz

    2009-07-01

    Full Text Available The patulin, (4hydroxy-4furo[3,2-c]pyran(6H-1,, is a thermal resistent mycotoxin produced by several species of fungi are common in plants, mainly in derivatives and apples. Studies on the toxicity in animals have shown that mycotoxin has character teratogenic, and carcinogenic in mice immunotoxic. Its biosynthesis is well understood involving a series of reactions of condensation and oxiredução, many catalyzed by enzymes. The danger of contamination of food with patulin, warning about the need for a more rigorous control. Recent research aimed their removal and degradation as well as increase the sensitivity of the tests, making them faster and at less cost. The removal of patulin of food is made with composite adsorbents, with inconvenience to diminish the quality of the product by adsorbs other components desirable. The degradation is made with sulfur compounds, which are not allowed in food in many countries, and the growth of yeasts, such as the production of cider. Many yeasts have resistance against patulin and produce compounds capable degrade it. Here, we reviewed research on patulin with emphasis on its influence in food industry, incidence of patulin in apple juice and other foods, maximum permissible concentrations, health effects, biosynthesis, removal, degradation and most widely used methods for its detection and quantification.A patulina, 4hidroxi-4furo[3,2-c] pirano(6H-1, micotoxina termo-resistente, é produzida por várias espécies de fungos, comuns em vegetais, produtos derivados e principalmente em maçãs. Estudos sobre a toxicidade em animais demonstraram esta micotoxina possui caráter teratogênico, cancerígeno e imunotóxico em camundongos. Sua biossíntese é bem compreendida envolvendo uma série de reações de condensação e de oxiredução, muitas catalisadas por enzimas. O perigo da contaminação de alimentos com patulina, alerta sobre a necessidade de um controle mais rigoroso. Pesquisas recentes objetivam

  17. Chemical constituents from branch of Fraxinus sieboldiana.

    Science.gov (United States)

    Lin, Sheng; Zhang, Yan-ling; Liu, Ming-tao; Zi, Jia-chen; Gan, Mao-luo; Song, Wei-xia; Fan, Xiao-na; Wang, Xiao-na; Yang, Yong-chun; Shi, Jian-gong

    2015-07-01

    ,5-dimethoxyphenyl)-1-propanone(34), 2,3-dihydroxy-1-(4-hydroxy-3-methoxyphenyl)-1-propanone (35), 3-hydroxy-l-(4-hydroxy-3,5-dimethoxyphenyl)-1-propanone(36), omega-hydroxypropioguaiacone(37), sinapyladehyde(38), trans-p-hydroxycinnamaldehyde(39), syringic acid(40), vanilic acid(41), vanillin(42), 4-hydroxy-benzaldehyde (43), (24R)-24-ethyl-5alpha-cholestane-3beta,5,6beta-triol(44), beta-sitosterol(45), daucosterol(46), 2,6-dimethoxy-I,4-benzoquinone(47), 2,6-dimethoxy-pyran-4-one(48), 1-(beta-D-ribofuranosyl)uracil(49), and mannitol(50). Compouds 1-7,12,18,28-37,44 and 48 were obtained from the genus Fraxinus for the first time.

  18. Radiotracers For Lipid Signaling Pathways In Biological Systems

    Energy Technology Data Exchange (ETDEWEB)

    Gatley, S. J. [Northeastern Univ., Boston, MA (United States)

    2016-09-26

    Bioorganic and Medicinal Chemistry Letters.Acylethanolamines. The work initially focused on myristoylethanolamine (MEA) labeled in the acyl moiety with tritium and with carbon-14. Standard coupling conditions were used and gave the desired radiotracers in decent yields. Tritiated product was needed for the search for binding sites of this signaling messenger, and C-14 labeled product for imaging using phosphorimaging screens. Additionally, C-14 MEA was prepared labeled in the ethanolamine moiety. Fluorine-18 labeled acylethanolamines. A multi-step synthesis was performed to obtain unlabeled N-(16- fluorohexadecanoyl)ethanolamide for an HPLC standard via the precursor 16-bromo-N- [2[(tetrahydro-2Hpyran-2-yl)oxy]ethyl]hexadecanoylamide. Near-anhydrous F-18 and the bromo precursor (approximately 2-3 mg) in acetonitrile (0.5 ml) were heated with a PETWave microwave reactor for 10 min at 80 °C. F-18 incorporation was checked using silica-gel TLC (8:92 methanol/chloroform). Deprotection was carried out using TFA. The crude product was purified by semi-preparative ODS HPLC (80:20 AcN/ H2O). The product peak was diluted in water, concentrated on an SPE column, and eluted in 1 mL EtOH. F-18 incorporation to form the THP protected product was >90% with negligible side products observed. Deprotection and HPLC purification proceeded successfully with >99% radiochemical l purity. Brain distribution studies were done in mice. This work was presented at the Society of Nuclear Medicine meeting in June 2012. Subsequent more detailed studies including whole body tissue distribution studies, microPET experiments and radiochromatographic studies were published in ACS Chemical Neurosciences in 2014. Iodine-125 labeled acylethanolamines. The precursor 12-bromo-N-[2[(tetrahydro-2H-pyran-2-yl)oxy]ethyl]dodecanoylamide was prepared and a 1 mg sample was subject to exchange labeling withradioiodide in refluxing acetonitrile for 1 hour. HPLC analysis as above indicated incorporation of about10% of

  19. Separation and Identification of Volatile Flavor Compounds in High-Salt Liquid State-Fermented Soy Sauce%高盐稀态酱油挥发性风味物质的分离与鉴定

    Institute of Scientific and Technical Information of China (English)

    高献礼; 赵谋明; 崔春; 曹鸣凯; 李丹

    2009-01-01

    分别采用固相微萃取(SPME)、同时蒸馏萃取(VSDE)和直接溶剂萃取(DSE)法对高盐稀态酱油挥发性风味物质进行分离、浓缩,并利用气质联用色谱(GC-MS)对其挥发性风味物质进行鉴定.试验共鉴定出147种风味化合物,其中酸类17种、醇类12种、醛类16种、酯类36种、呋喃(酮)类12种、酮类13种、杂环化合物14种、酚类8种、吡喃(酮)类6种、吡嗪类4种、吡咯(酮)类3种、含硫化合物6种.研究结果表明,主要挥发性风味化合物为酯、酸、醛、杂环化合物和醇类,其中酯类化合物的数量和相对含量最多;此外,有16种日式和韩式酱油中的关键风味化合物在国产高盐稀态酱油中被检出.%In this paper, such technologies as solid-phase micro-extraction (SPME), simultaneous steam distillation-extraction (VSDE) and direct solvent extraction (DSE) were employed to separate and concentrate the volatile flavor compounds in high-salt liquid state-fermented soy sauce, and the extracts were identified by means of gas chromatography-mass spectrometry (GC-MS). 147 flavor compounds, including 17 kinds of acids, 12 kinds of alcohols, 16 kinds of aldehydes, 36 kinds of esters, 12 kinds of furan(one)s, 13 kinds of ketones, 14 kinds of he-〖JP2〗 terocyclic compounds, 8 kinds of phenols, 6 kinds of pyran(one)s, 4 kinds of pyrazines, 3 kinds of pyrrol(idon)es〖JP〗 and 6 kinds of sulfur-containing compounds, were then identified. The results indicate that, in the dominant volatile flavor compounds in the soy sauce, namely, esters, acids, alcohols, aldehydes and heterocyclic compounds, esters are of the most species and of the highest relative content; and that 16 aroma-impact compounds of Japanese and Korean soy sauces were detected from Chinese high-salt liquid state-fermented soy sauce.

  20. Combined Pharmacological and Genetic Manipulations Unlock Unprecedented Temporal Elasticity and Reveal Phase-Specific Modulation of the Molecular Circadian Clock of the Mouse Suprachiasmatic Nucleus

    Science.gov (United States)

    Patton, Andrew P.; Chesham, Johanna E.

    2016-01-01

    The suprachiasmatic nucleus (SCN) is the master circadian oscillator encoding time-of-day information. SCN timekeeping is sustained by a cell-autonomous transcriptional–translational feedback loop, whereby expression of the Period and Cryptochrome genes is negatively regulated by their protein products. This loop in turn drives circadian oscillations in gene expression that direct SCN electrical activity and thence behavior. The robustness of SCN timekeeping is further enhanced by interneuronal, circuit-level coupling. The aim of this study was to combine pharmacological and genetic manipulations to push the SCN clockwork toward its limits and, by doing so, probe cell-autonomous and emergent, circuit-level properties. Circadian oscillation of mouse SCN organotypic slice cultures was monitored as PER2::LUC bioluminescence. SCN of three genetic backgrounds—wild-type, short-period CK1εTau/Tau mutant, and long-period Fbxl3Afh/Afh mutant—all responded reversibly to pharmacological manipulation with period-altering compounds: picrotoxin, PF-670462 (4-[1-Cyclohexyl-4-(4-fluorophenyl)-1H-imidazol-5-yl]-2-pyrimidinamine dihydrochloride), and KNK437 (N-Formyl-3,4-methylenedioxy-benzylidine-gamma-butyrolactam). This revealed a remarkably wide operating range of sustained periods extending across 25 h, from ≤17 h to >42 h. Moreover, this range was maintained at network and single-cell levels. Development of a new technique for formal analysis of circadian waveform, first derivative analysis (FDA), revealed internal phase patterning to the circadian oscillation at these extreme periods and differential phase sensitivity of the SCN to genetic and pharmacological manipulations. For example, FDA of the CK1εTau/Tau mutant SCN treated with the CK1ε-specific inhibitor PF-4800567 (3-[(3-Chlorophenoxy)methyl]-1-(tetrahydro-2H-pyran-4-yl)-1H-pyrazolo[3,4-d]pyrimidin-4-amine hydrochloride) revealed that period acceleration in the mutant is due to inappropriately phased

  1. Nickel-Catalyzed Reactions Directed toward the Formation of Heterocycles.

    Science.gov (United States)

    Kurahashi, Takuya; Matsubara, Seijiro

    2015-06-16

    Heterocycles have garnered significant attention because they are important functional building blocks in various useful molecules, such as pharmaceuticals, agricultural chemicals, pesticides, and materials. Several studies have been conducted regarding the preparation of heterocyclic skeletons with an emphasis on selectivity and efficiency. Three strategies are typically employed to construct cyclic molecules, namely, cyclization, cycloaddition, and ring-size alterations. Although each method has certain advantages, cycloaddition may be superior from the viewpoint of divergence. Specifically, cycloadditions enable the construction of rings from several pieces. However, the construction of heterocycles via cycloadditions is more challenging than the construction of carbocycles. For heterocycle construction, simple pericyclic reactions rarely work smoothly because of the large HOMO-LUMO gap unless well-designed combinations, such as electron-rich dienes and aldehydes, are utilized. Thus, a different approach should be employed to prepare heterocycles via cycloadditions. To this end, the use of metallacycles containing heteroatoms is expected to serve as a promising solution. In this study, we focused on the preparation of heteroatom-containing nickelacycles. Because nickel possesses a relatively high redox potential and an affinity for heteroatoms, several methods were developed to synthesize heteronickelacycles from various starting materials. The prepared nickelacycles were demonstrated to be reasonable intermediates in cycloaddition reactions, which were used to prepare various heterocycles. In this Account, we introduce the following four methods to prepare heterocycles via heteronickelacycles. (1) Direct oxidative insertion of Ni(0) to α,β-unsaturated enone derivatives: treatment of 3-ethoxycarbonyl-4-phenyl-3-buten-2-one with Ni(0) afforded an oxa-nickelacycle, which reacted with alkynes to give pyrans. (2) Substitution of a part of a cyclic compound with

  2. OLEDs under high current densities. Transient electroluminescence turn-on peaks and singlet-triplet quenching

    Energy Technology Data Exchange (ETDEWEB)

    Kasemann, Daniel

    2012-02-27

    This work focuses on a better understanding of the behavior of organic light emitting devices (OLEDs) under intense electrical excitation. Attaining high exciton densities in organic semiconductors by electrical excitation is of special interest for the field of organic semiconductor lasers (OSLs). In these devices, the high singlet exciton density needed in the active layer to obtain population inversion is easily created by pulsed optical pumping, but direct electrical pumping has not been achieved yet. First, the steps necessary to achieve stable high current densities in organic semiconductors are discussed. After determining the optimal excitation scheme using single p-doped transport layers, the device complexity is increased up to full p-i-n OLEDs with their power dependent emission spectra. For this purpose, two exemplary emitter systems are chosen: the fluorescent laser dye 4-dicyanomethylene-2-methyl-6-p-dimethylaminostyryl-4H-pyran (DCM) doped into Aluminum(III)bis (2-methyl-8-quinolinato)-4-phenylphenolate (Alq{sub 3}) and the efficient phosphorescent emitter system N,N'-di(naphthalen-1-yl)-N,N'-diphenyl-benzidine (alpha-NPD) doped by Iridium(III) bis(2-methyl-dibenzo[f,h]quinoxaline)(acetylacetonate) (Ir(MDQ){sub 2}(acac)). For pulsed excitation using 50 ns pulses and a repetition rate of 1 kHz, single 100 nm thin p- and n-doped transport layers sustain current densities of over 6 kA/cm{sup 2}. While the maximum current density decreases with increasing device thickness, the full OLEDs still sustain current densities beyond 800 A/cm{sup 2} and exhibit a continuously increasing emission intensity with increasing input power. Next, the time-resolved emission behavior of the singlet and triplet emitter device at high excitation densities is analyzed on the nanosecond scale. Here, the peak emission intensity of the phosphorescent emitter system is found to be more than eight times lower than for the singlet emitter system at comparable current

  3. Analysis of volatile components of three entomogenous fungi by SDE-GC-MS%SDE-GC-MS法分析三种虫生真菌菌丝中挥发性成分

    Institute of Scientific and Technical Information of China (English)

    李康乐; 包佳源; 陆瑞利; 张龙娃; 张德龙; 胡丰林

    2012-01-01

    Volatile components of Paecilomyces cicadae, Isaria gracilioides and Hirsutella heteropoda were extracted by method of simultaneous distillation extraction (SDE), and analyzed with gas chromatography-mass spectrometry (GC-MS). There were 44, 28 and 19 compounds were identified from the three species respectively. The main components were terpenoids, aromatic compounds, alcohols, alkanes, esters and aldehydes. Components' comparison revealed that butylated hydroxytoluene, 1-octen-3-ol, benzeneacetaldehyde and decamethyl-cyclopentasiloxane existedcommonly in all the 3 species. Besides the 3 main common components Paecilomyces cicadae contained uniquely 5-methylfurfuryl acetate, (E,E)-2,4-decadienal and decahydro-4,8,8-trimethyl-9-methylene-l,4-methanoazulene; Isaria gracilioides contained uniquely 5,6-dihydro-6-pentyl-2H-pyran-2-one, 2,4-dimethyl-oxazole, phenol and 1-ethenyl-l-methyl-2,4-bis(l-methylethenyl)-cyclohexane, and Hirsutella heteropoda contained uniquely 3,4,5-trimethoxy-Silane, (4-methoxyphenoxy)trimethyl-benzaldehyde, l,3-dimethyl-3,4,5,6-tetrahydro-2(lH)-pyrimidinone, and 9-octadecenoic acid(Z)-2-hydroxy-1 -(hydroxymethyl)ethyl ester.%采用同时蒸馏萃取-气相色谱质谱联用( SDE-GC-MS)的方法分析了蝉拟青霉、拟细羽束梗孢、根足被毛孢菌丝的挥发性成分,从中分别鉴定出44、28和19种化合物,它们主要为萜类化合物、芳香族化合物、醇类、烷烃类、酯类和醛类.成分比较发现,3种虫生真菌挥发性物质中有3种主要共有成分,分别为丁羟基甲苯、1-辛烯-3-醇、苯乙醛.除共有成分外,它们各自都有大量特有成分,其中蝉拟青霉主要有5-甲基-2-呋喃-乙酸酯、反式-2,4-癸二烯醛、长叶烯等;拟细羽束梗孢主要有5-羟基-2-癸烯酸-δ-内酯、2,4-二甲基-恶唑、苯酚、β-榄香烯等;根足被毛孢主要有3,4,5-三甲基-苯甲醛、1,3-二甲基-3,4,5,6-四氢化-2(1H)嘧啶、顺式-2-羟基-1-(羟甲基)-9-十八碳一烯酸乙酯.

  4. Bi- and tri-metallic Rh and Ir complexes containing click derived bis- and tris-(pyrazolyl-1,2,3-triazolyl) N-N' donor ligands and their application as catalysts for the dihydroalkoxylation of alkynes.

    Science.gov (United States)

    Vuong, Khuong Q; Wong, Chin M; Bhadbhade, Mohan; Messerle, Barbara A

    2014-05-28

    A series of bi-topic and tri-topic pyrazolyl-1,2,3-triazolyl donor ligands (; = 1,X-bis((4-((1H-pyrazol-1-yl)methyl)-1H-1,2,3-triazol-1-yl)methyl)benzene (X = 2, 3 and 4; o-C6H4(PyT)2, m-C6H4(PyT)2 and p-C6H4(PyT)2) and = 1,3,5-tris((4-((1H-pyrazol-1-yl)methyl)-1H-1,2,3-triazol-1-yl)methyl)benzene, 1,3,5-C6H3(PyT)3) were conveniently synthesised in 'one pot' reactions using the Cu(i) catalysed 'click' reaction. Rh(i), Ir(i), Rh(iii) and Ir(iii) complexes with ligands of the general formulae C6H6-n[(PyT)M(CO)2]n[BAr]n (M = Rh, Ir; n = 2, 3; ; ) and C6H6-n[(PyT)MCp*Cl]n[BAr]n (M = Rh, Ir; n = 2, 3; ; ) were synthesised and fully characterised. In solution each of the bi- or tri-metallic complexes and exists as a mixture of two (, ) or three ( and ) diastereomers due to the presence of a chiral centre at each metal centre in these complexes. The solid state structures of complexes and were determined by single crystal X-ray crystallography and showed that each bidentate arm of these multitopic ligands coordinates to the Rh or Ir centre in a bidentate fashion via the pyrazolyl-N2 and 1,2,3-triazolyl N3' donors. The intermetallic distances in these solid state structures vary from 8.66 Å to 15.17 Å. These complexes were assessed as catalysts for the dihydroalkoxylation of alkynes using the cyclisation of 2-(5-hydroxypent-1-ynyl)benzyl alcohol, , to a mixture of two spiroketals, 2,3,4,5-tetrahydro-spirol[furan-2,3'-isochroman], , and 3',4',5',6'-tetrahydro-spiro[isobenzofuran-1(3H),2'(2H)pyran], , as the model reaction. The Rh(i) complexes (), with the highest TOF of 2052 h(-1) for complex , were the most active catalysts when compared with the other complexes under investigation here. The Ir(i) complexes () were moderately active as catalysts for the same transformation. No significant enhancement in catalytic reactivity was observed with the Rh(i) series bi- and trimetallic complexes () when compared with their monometallic analogues. The bi- and trimetallic Ir

  5. Supercritical CO2 extraction on tobacco stem and application of stem extract in e-cigarette liquids%烟梗的超临界CO2流体萃取工艺及萃取物在电子烟中的应用

    Institute of Scientific and Technical Information of China (English)

    杨菁; 沈晓洁; 张怡春; 蔡振波; 陆诚玮; 郑赛晶

    2016-01-01

    In order to evaluate the potential of tobacco stems and develop a new e-cigarette flavor, supercritical fluid CO2 extraction technology was employed to extract aroma components in tobacco stems. The chemical components in the extract were analyzed by GC/MS, and the flavoring effect of the e-cigarette liquid was evaluated by sensory evaluation of the aerosol produced. The results showed that: 1) The optimal extraction parameters were: extraction pressure 20 MPa, extraction CO2 flow 5 L/min, extracting for 30 min at 120 ℃, and the yield was 9.9% of the stem by weight under such condition. 2) GC/MS identified 32 aroma components in tobacco stem; among them, the content of 2,3-dihydro-3,5-dihydroxy-6-methy-4H-pyran-4-one (DDMP) was higher, which was believed to mainly contribute to the roasted and tobacco-like aroma of the e-cigarette aerosol. 3) The obtained tobacco stem extract was shown to impart sweet, roasted and tobacco-like aroma to e-cigarette, and thus had the potential to aid the development of e-cigarettes of tobacco characteristic styles.%为开发新型电子烟烟液提取手段并实现烟梗的资源化利用,以超临界CO2流体萃取(SFE)工艺萃取烟梗末的香味物质,采用GC/MS法对萃取物的成分进行分析,并进行了电子烟加香效果评价。结果表明:①最佳萃取工艺条件为:萃取温度120℃,萃取流量5 L/min,萃取时间30 min,萃取压力20 MPa;此条件下烟梗末萃取物的产率为9.9%。②烟梗末样品萃取物经GC/MS分析共鉴定出32种主要成分,其中质量分数较高的2,3-二氢-3,5-二羟基-6-甲基-4H-吡喃-4-酮(DDMP)对电子烟烟气表现出的烘烤香和烟草本香具有重要贡献。③该法所制备的烟梗末萃取物为电子烟烟气赋予了甜的、烘烤的烟草香味,为特征风格电子烟产品的开发提供了潜在的应用价值。

  6. A Study on the Effect of Irradiation on Components in Cordyceps Sinensis (Berk.) Saccpowder Using Fourier Transform Infrared (FTIR) Spectroscopy%用傅立叶变换红外光谱法研究核辐照对虫草粉成分的影响

    Institute of Scientific and Technical Information of China (English)

    李家旺; 沙育年; 司民真

    2012-01-01

    本文采用傅立叶变换红外光谱(卷积谱及二阶导数谱)法对经不同剂量核辐照的虫草粉进行了对比研究.虫草粉中碳水化合物(糖和纤维素)、蛋白质及脂肪含量较高;虫草的多糖及酯对核辐照较为敏感,辐照还使分子中吡喃环的C-O-H基团向多糖的O-H和酯的C-O-C基团转化;构成虫草蛋白质的多肽是α构象的;低于18 kGy剂量辐照虫草粉样品对虫草蛋白质影响很小,但对虫草主要有效成分(含有C-N基团和N-H基团成分)影响较大;高于18 kGy剂量辐照虫草粉样品对虫草蛋白质、多糖及酯的分子结构可能产生了破坏.建议不宜采用核辐照对虫草粉杀菌消毒处理.%FTIR spectra of Cordyceps sinensis (Berk.) Sacc powder irradiated by y-ray with different doses were studied in the paper . Meanwhile, Fourier self-deconvolution curves and the second derivative specra for the irradiated Cordyceps sinensis (Berk. ) Sacc powder were also studied. The content of carbohydrate(sugar and cellulose) . protein and fat are higher in the Cordyceps sinensis (Berk. ) Sacc powder; y-ray irradiation for amy-lose and ester of Cordyceps sinensis (Berk.) Sacc powder is sensitiver, y-ray irradiation for Cordyceps sinensis (Berk. ) Sacc powder makes the group (C-O- H) of pyran ring of molecule toward the group (O-H) of sugar and the group (C-O-C) of ester; The poly-peptide that constitute protein of Cordyceps sinensis (Berk. ) Sacc are many α -configuration; It was found that the protein of the irradiated Cordyceps sinensis (Berk. ) Sacc powder with the under 18 kGy had almost no changes, however, the influence of the mainly effective composition (composition of group C-N and group N-H) of Cordyceps sinensis (Berk. ) Sacc powder is larger . The molecular structure of protein, amylose and cellulose of the irradiated Cordyceps sinensis (Berk. ) Sacc powder with the dose of beyond 18 kGy could be broken. It is suggested that the sterilization and

  7. Compositional analysis of bio-oil from pyrolysis of algae%海藻热解生物油的成分分析

    Institute of Scientific and Technical Information of China (English)

    王爽; 王谦; 徐姗楠; 姜秀民; 吉恒松; 何志霞

    2013-01-01

      为了明确海藻热解生物油的主要成分及热解工况对成分的影响,对海藻生物质(条浒苔、马尾藻)不同工况下热解制得的生物油进行气相色谱质谱联用分析。海藻类生物油成分除了含氮化合物外,主要是一些烃类、酮类、醛类、醇类和酚类化合物,以及较大分子量的羧酸及其衍生物,并包含了少量呋喃、吡喃、吡啶等衍生物的杂环化合物。条浒苔油中羧酸及其衍生物(37.85%)和烃类物质(16.61%)较多,而马尾藻生物油中甾族(30.16%)和醇类化合物(24.81%)较多,也检测出油酸、棕榈酸酯和花生酸。不同工况下产生的生物油在组成成分上非常相似,只是相对含量有所不同。热解温度对海藻油组分分布起了重要作用,而载气流量对热解海藻油组分分布的影响不明显。试验结果还表明海藻油中含氮化合物的形成主要与蛋白质的分解有关。海藻生物油相对于陆上植物热解生物油优点为高含烃量,低含氧量。海藻热解制油工艺中温度应控制在500~600℃之间,能达到较佳产油率和油品。%Though the work of pyrolysis of biomass for bio-oil has attained many achievements, the research on seaweed for bio-oil has been proceeding slowly. In this paper, fast pyrolysis experiments of algae biomass (Enteromorpha clathrata and Sargassum natans) were studied. Two kinds of algal bio-oil (Enteromorpha clathrata and Sargassum natans) obtained under different work conditions (400, 500, 600℃ and carried gas) were analyzed by using GC-MS analysis. Besides nitrogen-containing compounds, the major constituents of algal bio-oil were hydrocarbon, alcohols, ketones, aldehydes, and phenolic compounds, as well as large molecular weight carboxylic acids and their derivatives. The algal bio-oil also included a small amount of heterocyclic compounds (derivatives of furan, pyridine, pyran, etc.). It was seen from the

  8. PSP总日射表灵敏度系数的热偏移订正方法%Thermal Offset Correction Methods for Sensitivity of PSP Pyranometer

    Institute of Scientific and Technical Information of China (English)

    杨云; 丁蕾; 程兴宏; 权继梅; 彭继达

    2012-01-01

    The PSP pyranometer is used as a reference pyranometer and a reliable in strument in China. Before 2006 it is once used as national diffused reference to measure the reference diffused irradiance, the value of which is used in the sum composition method to calculate the reference global irradiance. The probability distribution of the nighttime thermal offsets within the pyranometers demonstrates near normal distribution. The offset of PSP type pyran-otneters is larger than that of 8-48 and CMP22 type. Finding the characteristics of the offset within different types of pyranometers and doing the calibration will improve the accuracy of diffused irradiance. The pyranometer calibration is done underclear sky. The negative thermal offset of the pyranometer causes that the sensitivity is underestimated. By the experiment and study on the thermal offset correction method for different type pyranometer, five correction methods are compared. The net longwave sensitivity method: Calculating the net longwave sensitivity of the pyranometer using longwave blackbody radiation, which is used in the sum composition method outdoors to correct the thermal offset of the pyranometer to reduce the offset effects. The differential algorithm with the reference global irradiance: Comparing it with the reference value derived from the sum composition method using the absolute cavity radiometer and CMP22 type secondary standard pyranometer with shading. The net longwave equation method: Analyzing the data of pyranometers and PIR type pyrgeometers measured at night to correct thermal offset. The cover method: Covering the dome of pyranometers in daytime to measure the offset of pyranometer directly. Using the voltage output of pyranometer in the nighttime as the thermal offset: Calculating the average voltage (night) when solar is 7° lower than horizon and transform it to irradiance as the thermal offset. When u-sing the sum composition method to calibrate PSP pyranometer, the correction

  9. Extraction and gelatinization characteristics of Chenopodium quinoa Willd starch based on ridge analysis%基于岭脊分析的藜麦淀粉提取及糊化特性研究

    Institute of Scientific and Technical Information of China (English)

    付丽红; 李晓斌

    2016-01-01

    minimize an estimated second-order correlation function on spheres of varying radius. According to the ridge analysis, the optimum parameters were as follows:solid-liquid ratio of 1:5 (g/mL), NaOH concentration of 0.2%and extraction time of 5.5 h. Under this condition, the extraction rate of starch was 98.94%±0.26%. The shape and chemical structure of starch granules were examined by the scanning microscope and Fourier transform infrared spectrometer. The starch granules of quinoa had irregular shape. The functional groups of quinoa starch contained-OH,-CH2,-CHO, C-O-C and pyran ring, and quinoa starch had typical molecular structure of native starch. And the 1 047 cm-1/1 022 cm-1 absorption peak ratio was 0.77. The gelatinization characteristics of starch were also studied, including swelling property, transmittance, freeze-thaw stability and retrogradation. The swelling property of quinoa starch was related to pasting temperature, and increased with the increasing of temperature. The swelling was divided into 2 stages: the initial swelling period and rapid swelling period. So, the quinoa starch was restricted swelling starch. And its highest swelling degree was 15.581 g/g at 95℃. The transmittance and retrogradation were closely related to standing time. The initial transmittance rate of starch was 1.7, which decreased with retention time. However, the retrogradation volumes increased with the time, which remained basically unchanged after 12 h. The syneresis rate was 10.50%during the first freeze-thaw cycle. The syneresis rate increased with the number of freeze-thaw cycles and entered stable value (33.01%) after 3 cycles. The texture properties of starch gelatinization were analyzed by TMS-Pro texture analyzer. The texture indices, which contained hardness, cohesion, elasticity, adhesiveness and chewiness, increased with the concentration of starch. Through rotational rheometer, the result showed that quinoa starch belonged to pseudoplastic fluid. When angular

  10. Radiotracers For Lipid Signaling Pathways In Biological Systems

    Energy Technology Data Exchange (ETDEWEB)

    Gatley, S. J. [Northeastern Univ., Boston, MA (United States)

    2016-09-26

    Bioorganic and Medicinal Chemistry Letters.Acylethanolamines. The work initially focused on myristoylethanolamine (MEA) labeled in the acyl moiety with tritium and with carbon-14. Standard coupling conditions were used and gave the desired radiotracers in decent yields. Tritiated product was needed for the search for binding sites of this signaling messenger, and C-14 labeled product for imaging using phosphorimaging screens. Additionally, C-14 MEA was prepared labeled in the ethanolamine moiety. Fluorine-18 labeled acylethanolamines. A multi-step synthesis was performed to obtain unlabeled N-(16- fluorohexadecanoyl)ethanolamide for an HPLC standard via the precursor 16-bromo-N- [2[(tetrahydro-2Hpyran-2-yl)oxy]ethyl]hexadecanoylamide. Near-anhydrous F-18 and the bromo precursor (approximately 2-3 mg) in acetonitrile (0.5 ml) were heated with a PETWave microwave reactor for 10 min at 80 °C. F-18 incorporation was checked using silica-gel TLC (8:92 methanol/chloroform). Deprotection was carried out using TFA. The crude product was purified by semi-preparative ODS HPLC (80:20 AcN/ H2O). The product peak was diluted in water, concentrated on an SPE column, and eluted in 1 mL EtOH. F-18 incorporation to form the THP protected product was >90% with negligible side products observed. Deprotection and HPLC purification proceeded successfully with >99% radiochemical l purity. Brain distribution studies were done in mice. This work was presented at the Society of Nuclear Medicine meeting in June 2012. Subsequent more detailed studies including whole body tissue distribution studies, microPET experiments and radiochromatographic studies were published in ACS Chemical Neurosciences in 2014. Iodine-125 labeled acylethanolamines. The precursor 12-bromo-N-[2[(tetrahydro-2H-pyran-2-yl)oxy]ethyl]dodecanoylamide was prepared and a 1 mg sample was subject to exchange labeling withradioiodide in refluxing acetonitrile for 1 hour. HPLC analysis as above indicated incorporation of about10% of