Sample records for dienes

  1. A Conversation with Zoltan P. Dienes

    Sriraman, Bharath; Lesh, Richard


    The name of Zoltan P. Dienes (1916- ) stands with those of Jean Piaget, Jerome Bruner, Edward Begle, and Robert Davis as a legendary figure whose work left a lasting impression on the field of mathematics education. Dienes' name is synonymous with the multibase blocks that he invented for the teaching of place value. Among numerous other things,…

  2. A Conversation with Zoltan P. Dienes

    Sriraman, Bharath; Lesh, Richard


    The name of Zoltan P. Dienes (1916- ) stands with those of Jean Piaget, Jerome Bruner, Edward Begle, and Robert Davis as a legendary figure whose work left a lasting impression on the field of mathematics education. Dienes' name is synonymous with the multibase blocks that he invented for the teaching of place value. Among numerous other things,…

  3. Method for producing diene hydrocarbons

    Tsaylingol' d, A.L.; Abayev, G.N.; Mikhaylov, R.K.; Stepanov, G.A.; Troitskiy, A.P.


    A method is claimed for producing diene hydrocarbons by oxidational dehydration of paraffin or olefin hydrocarbons in a fluidized bed of a concentrate with circulation of the latter between the zones of the reaction of regeneration with the help of circulation stand pipes. To increase the efectiveness of the process, it is proposed to circulate the concentrate between the zones of reaction and regeneration, sequentially disposed in a common apparatus with a difference in the concentration of the concentrate in the circulation stand pipes disposed in the same apparatus and the zone of the reaction equal to 20-700 kg/m/sup 3/. For example, the process of oxidational dehydration of butane through the proposed system is conducted in an apparatus with a diameter of 1,000 mm, a circulation stand pipe diameter of 500 mm, a linear gas speed in the reaction zone of 0.6 m/s, and in the circulation stand pipe of 0.15 m/s. The concentration of the concentrate in the dehydration zone is 640 kg/m/sup 3/ and in the stand pipe, 970 kg/m/sup 3/. The volumetric ratio of the n-C/sub 4/H/sub 10/:air, air:vapor vapor in the form of a condensate is 1:7.2:4.5:5.5. The output of the butadiene is: in the passed butane, 32.9% and in the broken down butane, 52.5%. The butane conversion is 62.6%. The losses of the concentrate with the contact gas and with the regeneration gases is 1/3 as much for the supplied butane, than in a known method. The method makes it possible to reduce the air expenditure by 60%, to reduce the concentrate losses by 2-3 times and to simplify the industrial system.

  4. 1,2-Selective Hydrosilylation of Conjugated Dienes

    Parker, Sarah Elizabeth


    Selective 1,2-hydrosilylation of 1,3-dienes is a challenging problem to solve for transition metal catalysis. Butadiene, specifically, would be a useful substrate because 3-butenylsilane products have promise as superior coupling reagents for hybrid organic/inorganic materials synthesis. In this thesis, we describe the first selective 1,2-hydrosilylation of conjugated dienes, including butadiene.

  5. Iridium-catalyzed annulation of salicylimines with 1,3-dienes.

    Ebe, Yusuke; Nishimura, Takahiro


    Iridium-catalyzed annulation of salicylimines with 1,3-dienes gave high yields of the corresponding 4-aminochromanes with high stereoselectivity. The use of a chiral diene ligand enabled the asymmetric reaction to give 4-aminochromanes with high enantioselectivity.

  6. Cyclization–endoperoxidation cascade reactions of dienes mediated by a pyrylium photoredox catalyst

    Nathan J. Gesmundo


    Full Text Available Triarylpyrylium salts were employed as single electron photooxidants to catalyze a cyclization–endoperoxidation cascade of dienes. The transformation is presumed to proceed via the intermediacy of diene cation radicals. The nature of the diene component was investigated in this context to determine the structural requirements necessary for successful reactivity. Several unique endoperoxide structures were synthesized in yields up to 79%.

  7. Influence of the Diene Monomer on Devulcanization of EPDM Rubber

    Verbruggen, M.A.L.; van der Does, L.; Noordermeer, Jacobus W.M.; van Duin, M.


    Ethylene–propylene–diene rubbers (EPDM) with 2-ethylidene-5-norbornene (ENB), dicyclopentadiene (DCPD), and 1,4-hexadiene (HD) as third monomers have been vulcanized with peroxide and with a conventional sulfur vulcanization recipe, and their devulcanization was subsequently investigated for

  8. Diastereoselective Desymmetrization of Symmetric Dienes and its Synthetic Application

    Kenji Nakahara


    Full Text Available The desymmetrization of symmetric compounds is a useful approach to obtain chiral building blocks. Readily available precursors with a prochiral unit could be converted into complex molecules with multiple stereogenic centers in a single step. In this review, recent advances in the desymmetrization of symmetric dienes in the diastereotopic group differentiating reaction and its synthetic application are presented.

  9. Diene complexes of titanium, zirconium, and hafnium. Structure and reactivity

    Blenkers, Johannes


    This thesis describes a study of synthesis, characterization, and reactivity of novel n4-diene complexes of group IVB transition metals in low valence states. In the study of the reactivity, emphasus is put on reactions with simple substrate molecules, e.g. CO, H2, olefins, isocanides; in particular

  10. Influence of the diene monomer on devulcanization of EPDM rubber

    Verbruggen, M.; Does, van der L.; Noordermeer, J.W.M.; Duin, van M.


    Ethylene–propylene–diene rubbers (EPDM) with 2-ethylidene-5-norbornene (ENB), dicyclopentadiene (DCPD), and 1,4-hexadiene (HD) as third monomers have been vulcanized with peroxide and with a conventional sulfur vulcanization recipe, and their devulcanization was subsequently investigated for recycli


    JIN Yingtai; ZHANG Xitian; PEI Fengkui; WU Yue


    The reaction mechanisms ofdiene polymerization with homogeneous rare earth catalyst are studied by means of the spectra of 1H- NM R, one- and two- dimensions 13C-NMR. Based on the data of above NMR spectra, it is proposed that the polymerization reaction proceeds according to the following mechanism: η4-diene (cis- (→)trans- )and η3-allyl (syn- (→)anti- ).

  12. Sulfonation of vulcanized ethylene-propylene-diene terpolymer membranes

    Barroso-Bujans, F. [Instituto de Ciencia y Tecnologia de Polimeros, CSIC, Juan de la Cierva 3, 28006 Madrid (Spain)], E-mail:; Verdejo, R.; Lozano, A. [Instituto de Ciencia y Tecnologia de Polimeros, CSIC, Juan de la Cierva 3, 28006 Madrid (Spain); Fierro, J.L.G. [Instituto de Catalisis y Petroleoquimica, CSIC, Marie Curie 2, Cantoblanco, 28049 Madrid (Spain); Lopez-Manchado, M.A. [Instituto de Ciencia y Tecnologia de Polimeros, CSIC, Juan de la Cierva 3, 28006 Madrid (Spain)


    In the present work, sulfonation of previously vulcanized ethylene propylene diene terpolymer (EPDM) membranes was developed in a swelling solvent with acetyl sulfate. This procedure avoids the need to pre-dissolve the raw polymer. The reaction conditions were optimized in terms of solvent type, reaction time, acetyl sulfate concentration and film thickness to obtain the maximum degree of sulfonation of the polymer. The sulfonation procedure presented in this study yields a degree of sulfonation comparable to the chlorosulfonic acid procedure. Sulfonic acid groups were detected by X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy, and quantified by titrations. Proton conductivity and water uptake were measured by means of impedance spectroscopy and swelling measurements, respectively, and were correlated with the degree of sulfonation. Tensile strength and Young's modulus of sulfonated EPDM increased with the degree of sulfonation, while elongation at break remained constant. Thermal stability of the sulfonated EPDM was studied by simultaneous thermogravimetry-mass spectroscopy.

  13. Highly stereoselective synthesis of functionalized 1,3-dienes from a new allyl bromide

    Asma Fray


    Full Text Available New and highly functionalized 1,3-dienes 3 and 4 have been synthesized via two different pathways starting from allyl bromide 1. Firstly, the reaction of allyl bromide 1 with triethylphosphite leads to an allylphosphonate 2, which undergoes the Wittig-Horner reaction with a range of saturated and unsaturated aldehydes gives rise to the corresponding 1,3-dienes 3. Secondly, a highly stereoselective reaction between allyl bromide 1 and nitroalkane salts, offers the possibility to obtaining functionalized (E-1,3-dienes 4.


    Veaceslav Kulciţki


    Full Text Available Conjugate 1,4-addition of N-bromosuccinimide (NBS to a diene system, possessing a suitable oxygen functionality, leads to functionalized tetrahydrofuran derivatives, which can be further derivatized into different synthetic targets.

  15. Novel copper(II)-dien-imidazole/imidazolate-bridged copper(II) complexes. Crystal structure of [Cu(dien)(Him)](ClO4)2 and of [(dien)Cu(mu-im)Cu(dien)](ClO4)3, a homobinuclear model for the copper(II) site of the CuZn-superoxide dismutase.

    Patel, R N; Singh, Nripendra; Shukla, K K; Chauhan, U K


    The imidazolate-bridged binuclear copper(II)-copper(II) complex [(dien)Cu(mu-im)Cu(dien)](ClO(4))(3) and related mononuclear complexes [Cu(dien)(H(2)O)](ClO(4))(2), [Cu(dien)(Him)](ClO(4))(2) were synthesized with diethylenetriamine (dien) as capping ligand. The crystal structure of mononuclear [Cu(dien)(Him)](ClO(4))(2) and binuclear complex [(dien)Cu(mu-im)Cu(dien)](ClO(4))(3) have been determined by single crystal X-ray diffraction methods. The mononuclear complex [Cu(dien)(Him)](ClO(4))(2) crystallizes in the orthorhombic, Pca2(1) with a = 9.3420(9) A, b = 12.3750(9) A, c = 14.0830(9) A, beta = 90.000(7)(o) and Z = 4 and binuclear complex [(dien)Cu(mu-im)Cu(dien)](ClO(4))(3) crystallizes in the monoclinic space group P2(1)/a, with a = 15.017(7) A, b = 11.938(6) A, c = 15.386(6) A, beta = 110.30(4)(o) and Z = 4. The molecular structures show that copper(II) ions in an asymmetrically elongated octahedral coordination (type 4 + 1 + 1) and in binuclear complex Cu(1) atom has a asymmetrically elongated octahedral coordination (type type 4 + 1 + 1) and Cu(2) atom exhibits a square base pyramidal coordination (type 4 + 1). The bridging ligand (imidazolate ion, im) lies nearly on a straight line between two Cu(2+), which are separated by 5.812 A, slightly shorter than the value in copper-copper superoxide dismutase (Cu(2)-Cu(2)SOD). Magnetic measurements and electron spin resonance (ESR) spectroscopy of the binuclear complex have shown an antiferromagnetic exchange interaction. From pH-dependent cyclic voltametry (CV) and electronic spectroscopic studies the complex has been found to be stable over a wide pH range (7.75-12.50).

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

    Philipp Röse


    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.

  17. Mechanism of cleaving DNA through hydrolysis of a novel complex of Mg containing dien ligand


    A series of metal complexes were designed and synthesized and a novel binuclear magnesium complex has been selected, namely [Mg2(dien)Cl(OH2)2]Cl2·H2O (dien=diethylene-triamine), which can cleave the plasmid pBR322 DNA effectively in close to physiological condition without adding any external materials.Through biological and chemical methods, especially the comparative experiments, we find the interaction between the complex and DNA belongs to hydrolytic mechanism.

  18. Spiro[2.4]hepta-4,6-dienes: synthesis and application in organic synthesis

    Menchikov, L. G.; Nefedov, O. M.


    This review integrates and describes systematically the data in the field of spiro[2.4]hepta-4,6-dienes published in the past 15 years. The changes in the development of studies that took place during this period are noted. The methods for the synthesis, the reactivity details and key chemical transformations of spiro[2.4]hepta-4,6-dienes are considered, with the emphasis on applications of these compounds in organic synthesis. The bibliography includes 207 references.

  19. Biaxial ordering of terminal diene groups in lipid membranes: an infrared linear dichroism study

    Binder, H.; Gutberlet, T.; Anikin, A.


    The molecular order within the hydrophobic core of membranes of the diene lipid di-tetradecadienoylphosphatidylcholine was studied by means of infrared spectroscopy on multibilayer assemblies which orient macroscopically on the surface of an attenuated total reflection crystal. The relative humidity and temperature were used as variable parameters to demonstrate that there were profound differences in the melting transition of lipids possessing predominantly cis and trans diene groups. The cis isomer undergoes the phase transition at a vapor pressure which is increased by ∽0.15 GPa when compared with that of the trans isomer. The methylene wagging band progression gives no indication of differences between the acyl chain conformation of the cis and trans forms in the gel state. The frequencies of a number of absorption bands of the diene groups reveal that these moieties are predominantly in the s-trans conformation to accommodate a favorable packing within the bilayer. The linear dichroism of selected in-plane and out-of-plane vibrations of the diene groups gives indications of the biaxial ordering of these moieties. We present the basic equations for the quantitative analysis of IR dichroism data of lamellar structures in terms of transverse and longitudinal molecular order parameters. It turns out that the planes of the rigid diene groups orient preferentially in a perpendicular direction with respect to the bilayer surface and parallel to each other forming in this way a layer of well-aligned diene groups in the bilayer center. This finding is confirmed by the results of X-ray measurements. We suggest that the partial interdigitation of the diene groups of the sn-1 acyl chains promotes the formation of the inverse H II phase and/or enables the formation of covalent bonds between both the monolayers upon polymerization of diene lipids.

  20. Solvent-free cyclization of linear dienes using olefin metathesis and the Thorpe-Ingold effect

    Forbees, M.D.E.; Myers, T.L.; Maynard, H.D.; Schulz, G.R. (Univ. of North Carolina, Chapel Hill (United States)); Patton, J.T.; Smith, D.W. Jr.; Wagener, K.B. (Univ. of Florida, Gainesville (United States))


    The olefin metathesis reaction is of great synthetic utility in polymer chemistry. The recent development of ring-opening (ROMP) and acyclic diene (ADMET) metathesis polymerization reactions has opened new avenues for the synthesis of novel polymeric materials. Recently the authors used ADMET to synthesize several photochemically active poly(keto olefins) using the catalyst Mo(CHCMe[sub 2]Ph)(NAr)(OCMe(CF[sub 3])[sub 2])[sub 2] (Ar = 2,6-diisopropylphenyl) (1) developed by Schrock and co-workers in 1990. In the course of that work, they discovered that neat samples of highly substituted dienes will cyclize quantitatively via metathesis to give difunctional five- and seven-membered rings instead of the expected linear polymer. Examples of substituted diene cyclizations by metathesis even in the presence of a solvent are rare. Their systematic exploitation in organic synthesis has therefore been limited to two recent studies by Fu and Grubbs, who cyclized several substituted diene ethers, amines, and amides to unsaturated oxygen and nitrogen heterocycles. Cyclization of unsubstituted dienes in various solvents has been reported, but complete conversion occurred in only a few cases. Formation of cyclic alkene oligomers from back-biting during the ROMP reaction is also known. The reactions reported here are unusual in that they are intermolecular between catalyst and substrate, yet can give 100% yield of product solely from the monomer in the absence of solvent. 13 refs.

  1. Silicon-containing alka-1,3-dienes and their functional derivatives in organic synthesis

    Stadnichuk, M. D.; Voropaeva, T. I.


    Data on the synthesis and chemical reactions of silicon-containing 1,3-dienes are surveyed for the first time in the present review. It is shown that the addition reactions of 1- and 2-triorganosilylalka-1,3-dienes and their derivatives are the most interesting and promising in fine organic synthesis. The application of the trialkylsilyl group as a protecting group and as a new reaction centre, which makes it possible to obtain carbon-carbon or carbon-heteroatom bonds, is examined. It has been found that the double bonds remote from the silicon atom are the most reactive in addition reactions and that regardless of the nature of the reagent the attacking species always binds to the terminal carbon atom of the buta-1,3-diene fragment. The bibliography includes 329 references.

  2. Oxidative Heck vinylation for the synthesis of complex dienes and polyenes.

    Delcamp, Jared H; Gormisky, Paul E; White, M Christina


    We introduce an oxidative Heck reaction for selective complex diene and polyene formation. The reaction proceeds via oxidative Pd(II)/sulfoxide catalysis that retards palladium-hydride isomerizations which previously limited the Heck manifold's capacity for furnishing stereodefined conjugated dienes. Limiting quantities of nonactivated terminal olefins (1 equiv) and slight excesses of vinyl boronic esters (1.5 equiv) that feature diverse functionality can be used to furnish complex dienes and polyenes in good yields and excellent selectivities (generally E:Z = >20:1; internal:terminal = >20:1). Because this reaction only requires prior activation of a single vinylic carbon, improvements in efficiency are observed for synthetic sequences relative to ones featuring reactions that require activation of both coupling partners.

  3. [2+2] cycloaddition of 1,3-dienes by visible light photocatalysis.

    Hurtley, Anna E; Lu, Zhan; Yoon, Tehshik P


    [2+2] photocycloadditions of 1,3-dienes represent a powerful yet synthetically underutilized class of reactions. We report that visible light absorbing transition metal complexes enable the [2+2] cycloaddition of a diverse range of 1,3-dienes. The ability to use long-wavelength visible light is attractive because these reaction conditions tolerate the presence of sensitive functional groups that might be readily decomposed by the high-energy UVC radiation required for direct photoexcitation of 1,3-dienes. The resulting vinylcyclobutane products are poised for a variety of further diversification reactions, and this method is consequently expected to be powerfully enabling in the synthesis of complex organic targets. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Synthesis of Ent-16-hydroxycleroda-4(18),13-dien-15,16-olide and Ent-cleroda-4(18),13-dien-15,16-olide from (+)-hardwickiic acid

    Ide, Regina M.; Imamura, Paulo M. [Universidade Estadual de Campinas, SP (Brazil). Inst. de Quimica]. E-mail:; Costa, Marta [Universidade Federal do Rio Grande do Norte, Natal, RN (Brazil). Dept. de Quimica


    The absolute configurations of two natural diterpene butenolides were confirmed through the synthesis of ent-16-hydroxycleroda-4(18),13-dien-15,16-olide (2) and ent-cleroda-4(18),13-dien- 15,16-olide (3), enantiomers of the natural products, starting from (+)-hardwickiic acid (1). (author)

  5. Preparation and Reaction Chemistry of Novel Silicon-Substituted 1,3-Dienes

    Partha P. Choudhury


    Full Text Available 2-Silicon-substituted 1,3-dienes containing non transferrable groups known to promote transmetallation were prepared by Grignard chemistry and enyne metathesis. These dienes participated in one pot metathesis/Diels-Alder reactions in regio- and diastereoselective fashions. Electron-rich alkenes showed the fastest rates in metathesis reactions, and ethylene, a commonly used metathesis promoter slowed enyne metathesis. 2-Pyridyldimethylsilyl and 2-thienyldimethylsilyl substituted Diels-Alder cycloadducts participated in cross-coupling chemistry and the 2-thienyldimethylsilyl substituted cycloadducts underwent cross-coupling under very mild reaction conditions.

  6. Remembering Zoltan Dienes, a Maverick of Mathematics Teaching and Learning: Applying the Variability Principles to Teach Algebra

    Gningue, Serigne Mbaye


    This paper is written in honor of Zoltan Paul Dienes, an internationally renowned mathematician and educator, who passed away in January 2014. It is an attempt to describe, analyze and apply Dienes' theory on how mathematical structures can be taught by applying his four principles of learning upon which he believed a teacher can base concept…

  7. Studies on ethylene-propylene-diene rubber modification by N-chlorothio-N-butyl-benzenesulfonamide

    Zhang, Hongmei; Datta, Rabin; Talma, Auke; Noordermeer, Jacobus W.M.


    N-Chlorothiosulfonamides have been used to modify ethylene-propylene-diene rubber (EPDM) to enhance the compatibility of EPDM in, e.g., natural rubber (NR)/butadiene rubber (BR)/EPDM blends for ozone resistance. N-Chlorothio-N-butyl-benzenesulfonamide (CTBBS) was selected as a representative for

  8. Asymmetric Cyclization of N-Sulfonyl Alkenyl Amides Catalyzed by Iridium/Chiral Diene Complexes.

    Nagamoto, Midori; Yanagi, Tomoyuki; Nishimura, Takahiro; Yorimitsu, Hideki


    Iridium/chiral diene complexes efficiently catalyzed the asymmetric cyclization of N-sulfonyl alkenyl amides to give the corresponding 2-pyrrolidone derivatives with high enantioselectivity. A mechanistic study revealed that the reaction proceeds via nucleophilic attack of the amide on the alkene moiety.

  9. Dien Hoetink. 'Bij benadering'. Biografie van een landbouw-juriste in crisis- en oorlogstijd

    Kamp, van J.E.


    A woman with a university degree who makes a career outside of the home was rather exceptional in the first half of the twentieth century. This biography about Dien Hoetink (1904-1945) describes her legal work in Dutch agriculture between 1933 and 1945.It attemps to answer the ques

  10. A nordehydroabietyl amide-containing chiral diene for rhodium-catalysed asymmetric arylation to nitroolefins.

    Li, Ruikun; Wen, Zhongqing; Wu, Na


    A highly enantioselective rhodium catalysed asymmetric arylation (RCAA) of nitroolefins with arylboronic acids is presented using a newly developed, C1-symmetric, non-covalent interacted, phellandrene derived, nordehydroabietyl amide-containing chiral diene under mild conditions. Stereoelectronic effects were studied, suggesting an activation of the bound substrate through the secondary amide as a hydrogen-bond donor.

  11. Domino reactions of 2-methyl chromones containing an electron withdrawing group with chromone-fused dienes.

    Gong, Jian; Xie, Fuchun; Ren, Wenming; Chen, Hong; Hu, Youhong


    Domino reactions of 2-methyl substituted chromones containing an electron withdrawing group at the 3-position with chromone-fused dienes synthesized a diverse range of benzo[a]xanthones and complicated chromone derivatives. These multiple-step reactions result in either two or three new C-C bonds without a transition metal catalyst or an inert atmosphere.

  12. Implicit Learning of Nonlocal Musical Rules: A Comment on Kuhn and Dienes (2005)

    Desmet, Charlotte; Poulin-Charronnat, Benedicte; Lalitte, Philippe; Perruchet, Pierre


    In a recent study, G. Kuhn and Z. Dienes (2005) reported that participants previously exposed to a set of musical tunes generated by a biconditional grammar subsequently preferred new tunes that respected the grammar over new ungrammatical tunes. Because the study and test tunes did not share any chunks of adjacent intervals, this result may be…

  13. Implicit Learning of Nonlocal Musical Rules: A Comment on Kuhn and Dienes (2005)

    Desmet, Charlotte; Poulin-Charronnat, Benedicte; Lalitte, Philippe; Perruchet, Pierre


    In a recent study, G. Kuhn and Z. Dienes (2005) reported that participants previously exposed to a set of musical tunes generated by a biconditional grammar subsequently preferred new tunes that respected the grammar over new ungrammatical tunes. Because the study and test tunes did not share any chunks of adjacent intervals, this result may be…

  14. Asymmetric Hetero Diels-Alder Reaction of Chiral Imines with Danishefsky' s Diene Catalyzed by Yb(OTf) 3

    QIAN, Chang- Tao; WANG, Long-Cheng; CHEN,Rui-Fang


    Rcaction of chirai imines with Danishefsky' s diene in the presence of a catalytic amount (20 mol% ) of ytterbium trffiate afforded the corresponding hetero Diels-Alder adducts with a moderate to good diastereoselectivity.

  15. 1,3-Dien-5-ynes: Versatile Building Blocks for the Synthesis of Carbo- and Heterocycles.

    Aguilar, Enrique; Sanz, Roberto; Fernández-Rodríguez, Manuel A; García-García, Patricia


    1,3-Dien-5-ynes have been extensively used as starting materials for the synthesis of a wide number of different carbo- and heterocycles. The aim of this review is to give an overview of their utility in organic synthesis, highlighting the variety of compounds that can be directly accessed from single reactions over these systems. Thus, cycloaromatization processes are initially commented, followed by reactions directed toward the syntheses of five-membered rings, other carbocycles and, finally, heterocycles. The diverse methodologies that have been developed for the synthesis of each of these types of compounds from 1,3-dien-5-ynes are presented, emphasizing the influence of the reaction conditions and the use of additional reagents in the outcome of the transformations.

  16. Photochemical reactivity of polyenes: from dienes to rhodopsin, from microseconds to femtoseconds.

    Liu, Robert S H; Hammond, George S


    In reviewing the photochemistry of polyenes (from dienes and trienes to the visual retinyl chromophore), we categorize condensed-phase photochemical reactivity of molecules into two groups: those from thermally equilibrated excited species and those from unequilibrated excited species. Classical theories on radiationless transitions are useful for rationalizing the reactivity of molecules belonging to the first set only. The second group includes many of the exciting ultrafast photochemical reactions reported recently for polyenes (including dienes and trienes), in some cases with rates faster than vibrational relaxation. Much of the excited singlet-state reactions of polyenes, including the Hula-twist mechanism of photoisomerization, have been integrated with concepts introduced in other ultrafast spectroscopic/photochemical studies. Taking into consideration the special environment of the retinyl chromophore in rhodopsin, we propose a new mechanism for the phototrigger that accounts for its unusually fast rate of isomerization.

  17. Diastereoselective Synthesis of γ-Substituted 2-Butenolides via (CDC)-Rh-Catalyzed Intermolecular Hydroalkylation of Dienes with Silyloxyfurans.

    Goldfogel, Matthew J; Roberts, Courtney C; Manan, Rajith S; Meek, Simon J


    Catalytic intermolecular hydroalkylation of dienes with silyloxyfuran nucleophiles is reported. Reactions are catalyzed by 5 mol % of a (CDC)-Rh complex and proceed in up to 87% yield and 6:1 dr (syn/anti) to provide allylic butenolides bearing vicinal stereocenters. Reactions proceed with terminal aryl and alkyl dienes and with modified silyl enol ether nucleophiles including a thiophenone variant. Utility of the products is demonstrated in the synthesis of a polypropionate anti,syn-stereotriad.

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

    Barker, Timothy J; Jarvo, Elizabeth R


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

  19. The direct oxidative diene cyclization and related reactions in natural product synthesis

    Juliane Adrian


    Full Text Available The direct oxidative cyclization of 1,5-dienes is a valuable synthetic method for the (diastereoselective preparation of substituted tetrahydrofurans. Closely related reactions start from 5,6-dihydroxy or 5-hydroxyalkenes to generate similar products in a mechanistically analogous manner. After a brief overview on the history of this group of transformations and a survey on mechanistic and stereochemical aspects, this review article provides a summary on applications in natural product synthesis. Moreover, current limitations and future directions in this area of chemistry are discussed.

  20. Chloridocyclohexyl[(1,2,5,6-η-cycloocta-1,5-diene]platinum(II

    Kwang Ha


    Full Text Available In the title complex, [Pt(C6H11Cl(C8H12], the PtII ion lies in a distorted square-planar environment defined by the Cl and cyclohexyl C atoms and the mid-points of the two π-coordinated double bonds of cycloocta-1,5-diene. As a result of the different trans influences of the Cl atom and the cyclohexyl group, the Pt—C bonds trans to the cyclohexyl group are longer than those trans to the Cl atom.

  1. Rh-Catalyzed rearrangement of vinylcyclopropane to 1,3-diene units attached to N-heterocycles

    Alberto Brandi


    Full Text Available Dienes embedded in quinolizidine and indolizidine structures can be prepared in four steps from cyclic nitrones and bicyclopropylidene. The key intermediates α-spirocyclopropanated N-heterocyclic ketones, generated via a domino 1,3-dipolar cycloaddition/thermal rearrangement sequence, were converted by Wittig methylenation to the corresponding vinylcyclopropanes (VCPs, which underwent rearrangement to 1,3-dienes in the presence of the Wilkinson Rh(I complex under microwave heating. The previously unexplored Rh(I-catalyzed opening of the VCP moiety embedded in an azapolycyclic system occurs at high temperature (110–130 °C to afford the corresponding 1,3-dienes in moderate yield (34–53%.

  2. Pregna-5,17(20)-dien-21-oyl amides affecting sterol and triglyceride biosynthesis in Hep G2 cells.

    Stulov, Sergey V; Mankevich, Olga V; Dugin, Nikita O; Novikov, Roman A; Timofeev, Vladimir P; Misharin, Alexander Yu


    Synthesis of series [17(20)Z]- and [17(20)E]-pregna-5,17(20)-dien-21-oyl amides, containing polar substituents in amide moiety, based on rearrangement of 17α-bromo-21-iodo-3β-acetoxypregn-5-en-20-one caused by amines, is presented. The titled compounds were evaluated for their potency to regulate sterol and triglyceride biosynthesis in human hepatoma Hep G2 cells in comparison with 25-hydroxycholesterol. Three [17(20)E]-pregna-5,17(20)-dien-21-oyl amides at a concentrations of 5 μM inhibited sterol biosynthesis and stimulated triglyceride biosynthesis; their regulatory potency was dependent on the structure of amide moiety; the isomeric [17(20)Z]-pregna-5,17(20)-dien-21-oyl amides were inactive.

  3. Inverse Vulcanization of Sulfur using Natural Dienes as Sustainable Materials for Lithium-Sulfur Batteries.

    Gomez, Iñaki; Leonet, Olatz; Blazquez, J Alberto; Mecerreyes, David


    Lithium-sulfur batteries are among the most promising next-generation battery systems due to the high capacity of sulfur as cathodic material. Beyond its interesting intrinsic properties, sulfur possesses a very low conductivity and complex electrochemistry, which involves the high solubility of the lithium sulfides in the electrolyte. These two characteristics are at the core of a series of limitations of its performance as active cathode material, which leads to batteries with low cyclability. Recently, inverse vulcanized sulfur was shown to retain capacity far better than elemental sulfur, leading to batteries with excellent cyclability. Nevertheless, the diene co-monomers used so far in the inverse vulcanization process are man-made molecules. Herein, a tentative work on exploring inverse vulcanization using two naturally available monomers, diallyl sulfide and myrcene, is presented. The inverse vulcanization of sulfur was successfully completed, and the resulting polymers were characterized by FTIR, NMR spectroscopy, differential scanning calorimetry, and thermogravimetric analysis. Afterwards these polymers were tested as cathodic materials in lithium-sulfur cells. The sulfur-natural dienes materials exhibited high capacity at different C rates and high lifetime over 200 cycles with very high capacity retention at a moderate C rate of C/5. Altogether, these materials made from inexpensive and abundant chemicals are an excellent option as sustainable materials for electrochemical energy storage.

  4. Synthesis of polymeric phosphine-carborane complexes Rh(I) and their catalytic properties in hydrogenation of olefins and dienes

    Kalinin, V.N.; Melnik, O.A.; Sakharova, A.A.; Frunze, T.M.; Zakharkin, L.I.; Borunova, N.V.; Sharf, V.Z.


    Methylmethacrylate copolymers with 1-isopropenyl-(3)-1,2-dicarbamdecaborate salts were synthesized which, after reaction with Rh(PPh/sub 3/)/sub 3/Cl were converted to polymeric phosphine-carborane complexes. Their catalytic properties in hydrogenation and isomerization of olefins and dienes were investigated. These catalysts were found to be highly active. Hydrogenation of dienes was not as rapid as that of olefins. The rates depended significantly on the solvent used. The unique aspect of this catalytic system is the fact that, even at the early synthetic stage, the labile hydrogen atom of dicarbamdecaborate anion shifts toward Rh forming a monohydride complex. 6 references, 3 figures.

  5. FEMA expert panel review of p-mentha-1,8-dien-7-al genotoxicity testing results

    Cohen, Samuel M.; Fukushima, Shoji; Gooderham, Nigel J.; Guengerich, F.P.; Hecht, Stephen S.; Rietjens, Ivonne M.C.M.; Smith, Robert L.; Bastaki, Maria; Harman, Christie L.; McGowen, Margaret M.; Taylor, Sean V.


    p-Mentha-1,8-dien-7-al is a naturally occurring cyclic alpha,beta-unsaturated aldehyde that is used as a flavoring substance throughout the world. Due to the chemical structure and the potential DNA reactivity of the alpha,beta-unsaturated carbonyl moiety, a battery of genotoxicity assays was req

  6. Novel polymer composites from waste ethylene-propylene-diene-monomer rubber by supercritical CO2 foaming technology.

    Jeong, Keuk Min; Hong, Yeo Joo; Saha, Prosenjit; Park, Seong Ho; Kim, Jin Kuk


    In this study, a composite has been prepared by mixing waste rubber, such as ethylene-propylene-diene-monomer and low-density poly ethylene foaming, with supercritical carbon dioxide. In order to optimise the foaming process of the waste ethylene-propylene-diene-monomer-low-density poly ethylene composite, the variations of pressure and temperature on the foamed Microcell formation were studied. As indicated in scanning electron microscope photographs, the most uniform microcellular pattern was found at 200 bar and 100 °C using 30% by weight of waste ethylene-propylene-diene-monomer. Carbon dioxide could not be dissolved uniformly during foaming owing to extensive cross-linking of the waste ethylene-propylene-diene-monomer used for the composite. As a result the presence of un-uniform microcells after foaming were observed in the composite matrix to impart inferior mechanical properties of the composite. This problem was solved with uniform foaming by increasing the cross-link density of low-density poly ethylene using 1.5 parts per hundred dicumyl peroxide that enhances composite tensile and compressive strength up to 57% and 15%, respectively. The composite has the potential to be used as a foaming mat for artificial turf.

  7. High-level production of amorpha-4,11-diene, a precursor of the antimalarial agent artemisinin, in Escherichia coli.

    Hiroko Tsuruta

    Full Text Available BACKGROUND: Artemisinin derivatives are the key active ingredients in Artemisinin combination therapies (ACTs, the most effective therapies available for treatment of malaria. Because the raw material is extracted from plants with long growing seasons, artemisinin is often in short supply, and fermentation would be an attractive alternative production method to supplement the plant source. Previous work showed that high levels of amorpha-4,11-diene, an artemisinin precursor, can be made in Escherichia coli using a heterologous mevalonate pathway derived from yeast (Saccharomyces cerevisiae, though the reconstructed mevalonate pathway was limited at a particular enzymatic step. METHODOLOGY/ PRINCIPAL FINDINGS: By combining improvements in the heterologous mevalonate pathway with a superior fermentation process, commercially relevant titers were achieved in fed-batch fermentations. Yeast genes for HMG-CoA synthase and HMG-CoA reductase (the second and third enzymes in the pathway were replaced with equivalent genes from Staphylococcus aureus, more than doubling production. Amorpha-4,11-diene titers were further increased by optimizing nitrogen delivery in the fermentation process. Successful cultivation of the improved strain under carbon and nitrogen restriction consistently yielded 90 g/L dry cell weight and an average titer of 27.4 g/L amorpha-4,11-diene. CONCLUSIONS/ SIGNIFICANCE: Production of >25 g/L amorpha-4,11-diene by fermentation followed by chemical conversion to artemisinin may allow for development of a process to provide an alternative source of artemisinin to be incorporated into ACTs.

  8. Evaluation of some antioxidants in radiation vulcanized ethylene-propylene diene (EPDM) rubber

    Abdel-Aziz, M.M.; Basfar, A.A. E-mail:


    Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) have been used to study the oxidation of {gamma}-ray vulcanized ethylene-propylene diene rubber (EPDM) stabilized with various types of antioxidants. The antioxidants used were pentaerythrityl tetrakis(3,5-di-tert-butyl(-4-hydroxyphenyl))propionate (Irganox 1010), Irganox 1035, Irganox 1520D, as primary antioxidants; Irganox B561 and Irganox B900, as synergistic blends; hindered amine light stabilizer (HALS), i.e. Tinuvin 622 LD; N-isopropyl-N-phenyl-p-phenylene diamine (IPPD) and trimethyl quinoline (TMQ) and their mixtures. The measurements were carried out under atmospheric conditions. The effects of antioxidant type and its selected concentration were determined and mechanism of reaction proposed.

  9. Evaluation of some antioxidants in radiation vulcanized ethylene-propylene diene (EPDM) rubber

    Abdel-Aziz, M. M.; Basfar, A. A.


    Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) have been used to study the oxidation of γ-ray vulcanized ethylene-propylene diene rubber (EPDM) stabilized with various types of antioxidants. The antioxidants used were pentaerythrityl tetrakis(3,5-di-tert-butyl(-4-hydroxyphenyl))propionate (Irganox 1010), Irganox 1035, Irganox 1520D, as primary antioxidants; Irganox B561 and Irganox B900, as synergistic blends; hindered amine light stabilizer (HALS), i.e. Tinuvin 622 LD; N-isopropyl- N-phenyl- p-phenylene diamine (IPPD) and trimethyl quinoline (TMQ) and their mixtures. The measurements were carried out under atmospheric conditions. The effects of antioxidant type and its selected concentration were determined and mechanism of reaction proposed.

  10. Surface characterisation of ethylene-propylene-diene rubber upon exposure to aqueous acidic solution

    Mitra, S.; Ghanbari-Siahkali, Afshin; Kingshott, P.


    but significantly different with respect to molar mass and the presence of long chain branching. Both rubbers contained 5-ethylidene-2-norbomene (ENB) as diene. Solution cast films of pure EPDM samples were exposed in two different acidic solutions, viz. chromosulphuric (Cr (VI)/H2SO4) and sulphuric acid (H2SO4....... Furthermore, 20% Cr (VI)/H2SO4 also attacked the allylic carbon-hydrogen (C-H) bonds of ENB resulting in more oxygenated species on the surface compared to 20% H2SO4 under identical conditions. Cr (VI) in the 20% Cr (VI)/H2SO4 was found to play an important role in alteration of surface chemistry. Studies...

  11. Gas-Phase Synthesis of 1-Silacyclopenta-2,4-diene.

    Yang, Tao; Dangi, Beni B; Thomas, Aaron M; Sun, Bing-Jian; Chou, Tzu-Jung; Chang, Agnes H H; Kaiser, Ralf I


    Silole (1-silacyclopenta-2,4-diene) was synthesized for the first time by the bimolecular reaction of the simplest silicon-bearing radical, silylidyne (SiH), with 1,3-butadiene (C4 H6 ) in the gas phase under single-collision conditions. The absence of consecutive collisions of the primary reaction product prevents successive reactions of the silole by Diels-Alder dimerization, thus enabling the clean gas-phase synthesis of this hitherto elusive cyclic species from acyclic precursors in a single-collision event. Our method opens up a versatile and unconventional path to access a previously rather obscure class of organosilicon molecules (substituted siloles), which have been difficult to access through classical synthetic methods.

  12. Vulcanization Kinetics and Mechanical Properties of Ethylene Propylene Diene Monomer Thermal Insulation

    Mohamad Irfan Fathurrohman


    Full Text Available The vulcanization kinetics of Ethylene-propylene diene monomer (EPDM rubber thermal insulation was studied by using rheometer under isothermal condition at different temperatures. The rheometry analysis was used to determining the cure kinetic parameters and predicting the cure time of EPDM thermal insulation. The experimental results revealed that the curing curves of EPDM thermal insulation were marching and the optimum curing time decreased with increasing the temperature. The kinetic parameters were determined from the autocatalytic model showed close fitting with the experimental results, indicating suitability of autocatalytic model in characterizing the cure kinetics. The activation energy was determined from the autocatalytic model is 46.3661 kJ mol-1. The cure time were predicted from autocatalytic model and the obtained kinetic parameter by using the relationship among degree of conversion, cure temperature, and cure time. The predictions of cure time provide information for the actual curing characteristic of EPDM thermal insulation. The mechanical properties of EPDM thermal insulation with different vulcanization temperatures showed the same hardness, tensile strength and modulus at 300%, except at temperature 70 °C, while the elongation at breaking point decreased with increasing temperature of vulcanization. © 2015 BCREC UNDIP. All rights reservedReceived: 8th April 2014; Revised: 7th January 2015; Accepted: 16th January 2015How to Cite: Fathurrohman, M.I., Maspanger, D.R., Sutrisno, S. (2015. Vulcanization Kinetics and Mechanical Properties of Ethylene Propylene Diene Monomer Thermal Insulation. Bulletin of Chemi-cal Reaction Engineering & Catalysis, 10 (2, 104-110. (doi:10.9767/bcrec.10.2.6682.104-110Permalink/DOI: 

  13. Antiproliferative activity of mixed-ligand dien-Cu(II) complexes with thiazole, thiazoline and imidazole derivatives.

    Bolos, C A; Papazisis, K T; Kortsaris, A H; Voyatzi, S; Zambouli, D; Kyriakidis, D A


    The reaction of [Cu(dien)NO(3)]NO(3) with 2-amino-5-methylthiazole (2A5MT), 2-amino-2-thiazoline (2A-2Tzn), imidazole (im), N,N'-thiocarbonyldiimidazole (Tcdim), 2-aminothiazole (2AT) and 2-ethylimidazole (2Etim), gave a new series of mixed-ligand compounds of the general formula [Cu(dien)(B)NO(3))]NO(3); (dien, diethylenetriamine; B, 2A5MT, 2A-2Tzn, im, Tcdim, 2AT and 2Etim). The complexes have been characterised by elemental analysis, molar conductivity and magnetic measurements, as well as by electronic and IR spectral studies. According to the above measurements the possible structure of the compounds is the square pyramidal in the solid state and the square planar in aqueous solution. We tested all complexes for antiproliferative (cytostatic and cytotoxic) activity against a panel of cell lines (HeLa, L929, HT-29 and T47D). All [(dien)Cu(B)NO(3))](NO(3)) complexes had an activity against colon cancer cells (HT-29), inducing G2/M cell cycle arrest, an effect that for most of the complexes could be attributed to p34cdc2 inhibition by tyrosine-phosphorylation and/or to induction of (cyclin-dependent kinase inhibitor) p21(WAF1). Other cell lines were resistant to the majority of the complexes, except [Cu(dien)(2A5MT)NO(3))](NO(3)), that had showed the highest anti-proliferative activity against HT-29 cells also. The predilection for colon cancer cells and the relatively low toxicity against normal (L929) cells justify further investigation of this group of compounds.

  14. Protonated 14-membered 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetrazacyclotetradeca-7,14-diene Salts and Their Biological Activity

    Siti Fairus M. Yusoff


    Full Text Available The 14-membered heterocyclic 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetrazacyclotetradeca-7,14-diene, [(Me6[14]N4diene], salts with structural formula of [(Me6[14]N4diene]Br2(H2O2, [(Me6[14]N4dieneCl2](H2O3, Me6[14]N4diene.(ClO42, Me6[14]N4diene.(PF62¬  and   Me6[14]N4diene.(NO32   have been  synthesized without the necessity of a template. The salts were characterized by FTIR, and NMR spectroscopic techniques. X-ray study showed that the macrocyclic cation consists of a pair of protonated amines and azomethine nitrogen atoms located diagonally and opposite to each other. Only the macrocylic bromide and perchlorate salts showed activity against gram-positive E. faecalis and gram-negative E. Coli.

  15. Catalyst-free synthesis of skipped dienes from phosphorus ylides, allylic carbonates, and aldehydes via a one-pot SN2' allylation-Wittig strategy.

    Xu, Silong; Zhu, Shaoying; Shang, Jian; Zhang, Junjie; Tang, Yuhai; Dou, Jianwei


    A catalyst-free allylic alkylation of stabilized phosphorus ylides with allylic carbonates via a regioselective SN2' process is presented. Subsequent one-pot Wittig reaction with both aliphatic and aromatic aldehydes as well as ketenes provides structurally diverse skipped dienes (1,4-dienes) in generally high yields and moderate to excellent stereoselectivity with flexible substituent patterns. This one-pot SN2' allylation-Wittig strategy constitutes a convenient and efficient synthetic method for highly functionalized skipped dienes from readily available starting materials.

  16. Iridium-catalyzed [3 + 2] annulation of cyclic N-sulfonyl ketimines with 1,3-dienes via C-H activation.

    Nishimura, Takahiro; Ebe, Yusuke; Hayashi, Tamio


    Ir-catalyzed [3 + 2] annulation of cyclic N-sulfonyl ketimines with 1,3-dienes, in which an aryliridium intermediate is formed via C-H activation, gives aminoindane derivatives in high yields with high regio- and diastereoselectivity.

  17. Gold-catalyzed reactions of propargylic esters with vinylazides for the synthesis of Z- or E-configured buta-1,3-dien-2-yl esters.

    Wagh, Sachin Bhausaheb; Liu, Rai-Shung


    Gold-catalyzed synthesis of buta-1,3-dien-2-yl esters by the reaction of propargyl esters with vinylazides is described; the reaction mechanism is postulated to involve a vinyl attack of vinylazides at alkenyl gold carbenes.

  18. Structural determination of ethylene-propylene-diene rubber (EPDM) containing high degree of controlled long-chain branching

    Mitra, Susanta; Jørgensen, Mikkel; Pedersen, Walther Batsberg


    This work highlights an attempt to characterize the degree and nature of long-chain branching (LCB) in an unknown sample of ethylene-propylene-diene rubber (EPDM). Two EPDM rubbers selected for this study were comparable in comonomer compositions but significantly different with respect to molar...... mass and the presence of LCB. Both rubbers contained 5-ethylidene-2-norbornene (ENB) as diene. Solution cast films of pure EPDM samples were used for different characterization techniques. 1H-NMR, and 13C-NMR were used for assessing the comonomer ratios and LCB. Size exclusion chromatography (SEC...... findings and the available theories, an attempt was made to identify the chemical nature and degree of LCB. This study reveals the possibility of detailed characterization of molecular architecture of EPDM containing LCB by comparing with an essentially linear EPDM in light of an existing theory. © 2009...

  19. Crystal structure of trans-1,4-bis[(trimethylsilyloxy]cyclohexa-2,5-diene-1,4-dicarbonitrile

    Florian Glöcklhofer


    Full Text Available The asymmetric unit of the title compound, C14H22N2O2Si2, contains one half of the molecule, which is completed by inversion symmetry. The cyclohexa-2,5-diene ring is exactly planar and reflects the bond-length distribution of a pair of located double bonds [1.3224 (14 Å] and two pairs of single bonds [1.5121 (13 and 1.5073 (14 Å]. The tetrahedral angle between the sp3-C atom and the two neighbouring sp2-C atoms in the cyclohexa-2,5-diene ring is enlarged by about 3°.

  20. Ruthenium-catalyzed intramolecular metathesis of dienes and its application in the synthesis of bridged and spiro azabicycles

    Kuznetsov, N. Yu; Bubnov, Yu N.


    The review presents a historical excursion into catalytic alkene metathesis, covering the problems of history of the discovery of this process, as well as investigations on the properties, structure and reactivity of the most popular ruthenium catalysts for metathesis, mechanism of their action and decomposition. The main part covers studies devoted to the syntheses of bridged azabicyclic and 1-azaspirocyclic compounds comprising the intramolecular metathesis of dienes as the key step. The formation of a bicyclic skeleton of a series of natural bridged (cocaine, ferruginine, calystegines, and anatoxin-a) and spiro (pinnaic acids, halichlorine, hystrionicotoxin, and cephalotaxine) azabicycles, as well as their analogues and compounds with larger rings is demonstrated. The methods for the synthesis of diene precursors and the conditions for final assembling of the bicyclic compounds are considered in detail. The generalization of the literature data allows one to efficiently carry out the mentioned process taking into account the most important features. The bibliography includes 129 references.

  1. Synthesis, crystal structure and properties of [(dien)2Mn]Ge2S4 with mixed-valent Ge centers

    Yue, Cheng-Yang; Yuan, Zhuang-Dong; Zhang, Lu-Ge; Wang, Ya-Bai; Liu, Guo-Dong; Gong, Liao-Kuo; Lei, Xiao-Wu


    One new manganese thiogermanate, [(dien)2Mn]Ge2S4 (dien=diethylenetriamine), was prepared under mild solvothermal conditions and structurally and spectroscopically characterized. The title compound crystallizes in the orthorhombic system, chiral space group P212121 (no. 19) with a=9.113(4) Å, b=12.475(5) Å, c=17.077(7) Å, V=1941.5(15) Å3 and Z=4. Its structure features a three-dimensional (3D) network composed of a one-dimensional (1D) [Ge2S4]2- anionic chain and a [(dien)2Mn]2+ complex interconnected via various hydrogen bonds. The most interesting structural feature of the compound is the presence of two different oxidation states of germanium centers in the 1D [Ge2S4]2- chain, which is also supported by the result of X-ray photoelectron spectroscopy measurement. The optical property of the title compound has also been studied by UV-vis spectra.

  2. Structure aggregation of carbon black in ethylene-propylene diene polymer


    Full Text Available The modulus of filled and unfilled Ethylene-propylene diene rubber (EPDM vulcanizates was used to predict the shape-factor of carbon black aggregation in the polymer. Four types of carbon black that vary in particle size and structure were used in this study. Quadratic curves relating the carbon black volume concentration and the modulus ratio of filled and unfilled rubber vulcanizates were used to adopt the shape factor of certain carbon black type. The shape factor of MT, HAF, SRF and Lampblack were 3, 3.75, 4 and 4.25 respectively. X-ray diffraction technique (XRD was also used to evaluate the relative size of crystallite on the filler surface to that of the rubber and correlating it to the shape factor of carbon black aggregation in the polymer. Effect of the pH values and structure of carbon blacks used on the shape factor of filler aggregates were also studied. It was found that the shape factor is independent on the particle size while it is dependent on the pH value and structure of carbon black. Also the crystallites size of the filler is proportional to the shape factor.

  3. Response of ethylene propylene diene monomer rubber (EPDM) to simulant Hanford tank waste



    This report presents the findings of the Chemical Compatibility Program developed to evaluate plastic packaging components that may be incorporated in packaging mixed-waste forms for transportation. Consistent with the methodology outlined in this report, the author performed the second phase of this experimental program to determine the effects of simulant Hanford tank mixed wastes on packaging seal materials. That effort involved the comprehensive testing of five plastic liner materials in an aqueous mixed-waste simulant. The testing protocol involved exposing the materials to {approximately}143, 286, 571, and 3,670 krad of gamma radiation and was followed by 7-, 14-, 28-, 180-day exposures to the waste simulant at 18, 50, and 60 C. Ethylene propylene diene monomer (EPDM) rubber samples subjected to the same protocol were then evaluated by measuring seven material properties: specific gravity, dimensional changes, mass changes, hardness, compression set, vapor transport rates, and tensile properties. The author has determined that EPDM rubber has excellent resistance to radiation, this simulant, and a combination of these factors. These results suggest that EPDM is an excellent seal material to withstand aqueous mixed wastes having similar composition to the one used in this study.

  4. Socialkonstruktivisme, sprog og identitet: Identitetsforhandlinger på Eva Dien Brine Markvoorts sygdomsblog 65 Red Roses

    Carsten Stage


    Full Text Available Socialkonstruktivismen har været genstand for heftig kritik for at understøtte en form for begrebsrelativisme, der påstår, at virkeligheden skabes af vores begreber om den. Et delmål med artiklen er at gøre op med denne karikatur af konstruktivismen som en homogen teoretisk position, der reducerer alt til sprog og italesættelse eller indebærer en tro på, at alle identiteter blot er effekter af begreber. Dette gøres ved at præsentere og diskutere teorier af bl.a. Michel Foucault, Ernesto Laclau og Chantal Mouffe, Judith Butler, Stuart Hall, Karl Popper og Richard Jenkins med det formål at kunne skelne mellem forskellige former for, eller grader af, konstruktivisme. De forskellige konstruktivismeformers udsigelseskraft diskuteres dernæst gennem en analyse af et medieobjekt – Eva Dien Brine Markvoorts sygdomsblog 65 Red Roses.

  5. An investigation on changes in chemical properties of pure ethylene-propylene-diene rubber in aqueous acidic environments

    Mitra, S.; Ghanbari-Siahkali, Afshin; Kingshott, Peter


    The influence of two aqueous acidic environments on two types of pure ethylene-propylene-diene (EPDM) rubber (i.e., elastomer) thin films is studied. Attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) results revealed the formation of several oxygenated species...... formation on the surface of EPDM rubbers compared to 20% H2SO4 under identical conditions. Complex formation on the surface of EPDM samples exposed to 20% Cr(VI)/H2SO4 through reactions of carboxylic groups (generated due to EPDM degradation) with Cr(III) (formed due to reduction of Cr(VI)) was also evident...

  6. Synthesis of 1,7-Bis(4-hydroxyphenyl)hepta-4E,6E-dien-3-one

    XU,Guang-Bing; LI,Shao-Bai


    @@ Diarylheptanoids, most of which appearing in the areas of anti-inflammatory, anti-oxidative, super-oxide scavenging and anti-hepatotoxic effects, constitute a distinct group of metabolites of natural plants characterized by two aromatic rings linked by a linear seven aliphatic chain. We have investigated this kind of compounds and made some progress.[1]1,7-Bis(4-hydroxy-phenyl)hepta-4E,6E-dien-3-one (1) was firstly isolated from the seeds of Alpinia blepharocalyx.[2] So far the synthesis of the compound has not been reported yet. Herein, we report the synthesis of compound 1. The synthetic route is outlined in Scheme 1.

  7. From linden flower to linden honey. Part 2: Glycosidic precursors of cyclohexa-1,3-diene-1-carboxylic acids.

    Frérot, Eric; Velluz, Alain; Decorzant, Erik; Naef, Regula


    The presence of two unusual, recently identified terpene acids, i.e., 4-(1-hydroxy-1-methylethyl)cyclohexa-1,3-diene-1-carboxylic acid (1) and 4-(1-methylethenyl)cyclohexa-1,3-diene-1-carboxylic acid (2), was now also confirmed in (Swiss) linden honey, after solid-phase extraction and HPLC purification. NMR Spectroscopy, in combination with UPLC/MS analysis, showed the presence of several glycosides of 1, which accounted for ca. 0.6 weight-% of the honey, as quantified by UPLC-UV. The major 'glycoside' of 1, compound 5, could be isolated and identified by 2D-NMR experiments as the corresponding beta-gentiobiosyl ester (rather than the classical compound with a glycosidic bond between an aglycone OH group and the sugar). The same diglycosides found in linden honey were also detected in linden nectar; also, chestnut and fir honeys contained these glycosides in minor quantities, but not colza, acacia, or dandelion honeys (Table 2).

  8. Removal of Inorganic Nutrient and Organic Carbon from Wastewater of Binh Dien Market Using Green Alga Chlorella sp

    Ha Bui Manh


    Full Text Available Traditional markets play a major role in socio-economics and constitutes a significant aspect of Vietnamese culture. However, wastewater streams discharged from the markets are generally characterized by a lot of inorganic nutrients and organic substances originated from fresh food processing units. They could lead to serious water contamination if discharged without proper treatment. This study applied microalgae Chlorella sp. for eliminating inorganic nutrients (NO3−-N, NH4+-N and PO43−-P and organic carbon (Chemical oxygen demand-COD from wastewater of the Binh Dien market. The removal efficiencies reached for NH4+-N > 86%, for NO3−-N > 72%, and for PO43−-P > 69%, respectively, at algal density of 49 × 104 cell mL−1, and for COD > 96% at algal density of 35 × 104 cell mL−1 after five cultivating days. The effluence satisfied the Vietnamese standard, column B, of the National technical regulation on industrial wastewater (QCVN 40:2011/BTNMT. The results demonstrated that the culture system composed of green algal Chlorella sp. could be a potential candidate for the removal of nutrients and organic carbon by a wastewater treatment process from the Binh Dien market.

  9. A novel dry chemical path way for diene and dienophile surface functionalization toward thermally responsive metal-polymer adhesion.

    Moreno-Couranjou, Maryline; Manakhov, Anton; Boscher, Nicolas D; Pireaux, Jean-Jacques; Choquet, Patrick


    In this paper, we report a new and easily up-scalable dry chemical method to functionalize with diene and dienophile groups a large range of surfaces, such as metal, polymer, or glass, and we demonstrate the potentiality of this technique to realize thermally responsive adhesion between these materials. A complete and extensive surface chemistry analysis of the grafted surfaces, based on the deposition of an anhydride-rich thin plasma polymer layer by using an atmospheric pressure dielectric barrier discharge (DBD) plasma process, and its subsequent gas phase aminolysis reaction with specific diene or dienophile compound is discussed. The optimization of the assembling condition for these tailored surfaces has led to achieve a Diels-Alder adhesion force up to 0.6 N/mm at ambient temperature, which can be reduced by a factor of 50 when the retro Diels-Alder is ignited at a heating temperature around 200 °C. The study of the failure interface produced after peeling tests is presented and a mechanism of failure is proposed, based on forensic analyses involving surface analytical techniques such as XPS, ToF-SIMS, and SEM combined to AFM analyses for the retrieving of chemical and morphological information.

  10. Morphology-properties relationship on nanocomposite films based on poly(styrene-block-diene-block-styrene copolymers and silver nanoparticles


    Full Text Available A comparative study on the self-assembled nanostructured morphology and the rheological and mechanical properties of four different triblock copolymers, based on poly(styrene-block-diene-block-styrene and poly(styrene-block-diene-block-styrene matrices, and of their respective nanocomposites with 1 wt% silver nanoparticles, is reported in this work. In order to obtain well-dispersed nanoparticles in the block copolymer matrix, dodecanethiol was used as surfactant, showing good affinity with both nanoparticles and the polystyrene phase of the matrices as predicted by the solubility parameters calculated based on Hoftyzer and Van Krevelen theory. The block copolymer with the highest PS content shows the highest tensile modulus and tensile strength, but also the smallest elongation at break. When silver nanoparticles treated with surfactant were added to the block copolymer matrices, each system studied shows higher mechanical properties due to the good dispersion and the good interface of Ag nanoparticles in the matrices. Furthermore, it has been shown that semiempirical models such as Guth and Gold equation and Halpin-Tsai model can be used to predict the tensile modulus of the analyzed nanocomposites.

  11. A novel 3α-p-Nitrobenzoylmultiflora-7:9(11)-diene-29-benzoate and two new triterpenoids from the seeds of zucchini (Cucurbita pepo L).

    Tanaka, Reiko; Kikuchi, Takashi; Nakasuji, Saori; Ue, Yasuhiro; Shuto, Daisuke; Igarashi, Keishi; Okada, Rina; Yamada, Takeshi


    Three novel multiflorane-type triterpenoids, 3α-p-nitrobenzoylmultiflora-7:9(11)-diene-29-benzoate (1), 3α-acetoxymultiflora-7:9(11)-diene-29-benzoate (2), and 3α-acetoxymultiflora-5(6):7:9(11)-triene-29-benzoate (3), along with two known related compounds 4 and 5 were isolated from the seeds of zucchini (Cucurbita pepo L). Their structures were determined on the basis of 1D and 2D NMR spectroscopy and HREIMS. Triterpenoids possessing a nitro group were not isolated previously.

  12. A solid-state trimerisation of a diene diacid affords a bicyclobutyl: reactant structure from X-ray powder data and product separation and structure determination via co-crystallisation.

    Atkinson, Manza B J; Halasz, Ivan; Bučar, Dejan-Krešimir; Dinnebier, Robert E; Mariappan, S V Santhana; Sokolov, Anatoliy N; MacGillivray, Leonard R


    A bicyclobutyl that bears six carboxylic acid groups results from a trimerisation of a diene diacid in the solid state. Powder X-ray diffraction and a co-crystallisation are used to solve the structure of the diene and elucidate the stereochemistry of the bicyclobutyl, respectively.

  13. Design, synthesis, and biological evaluation of simplified analogues of (+)-discodermolide. Additional insights on the importance of the diene, the C7 hydroxyl, and the lactone.

    Smith, Amos B; Xian, Ming


    [structure: see text] The design, synthesis, and biological evaluation of seven totally synthetic analogues of the antitumor agent (+)-discodermolide are reported. Saturation of the terminal diene system, alteration of the substituents on the lactone, and alkylation of the C7-hydroxyl group reveal significant structure-activity relationships.

  14. The first facile total synthesis of natural(3R,4R,6S)-3,4-epoxybisabola-7(14),10-dien-2-one

    Zhi Yong Tang; Chen Xi Zhang; Li Jing Fang; Yu Lin Li


    3,4-Epoxybisabola-7(14),10-dien-2-one,a natural sesquiterpoind,was first synthesized from(-)-carvone through 7 steps,in an overall yield of 35.9%.The key step was the allylation and then a substrate-directable epoxidation was committed successfully.

  15. 19a-hydroxy-3-oxo-ursa-1,12-dien-28-oic acid, an antiplasmodial triterpenoid isolated from Canthium multiflorum

    Traore, Maminata; Ziegler, Hanne Lindvig; Olsen, C Erik


    A bioactivity guided fractionation of roots of Canthium multiflorum led to the isolation of the new ursenoic acid derivative 19alpha-hydroxy-3-oxo-ursa-1,12-dien-28-oic acid (1), which showed antiplasmodial effect without inducing change of the shape of membranes of erythrocytes....

  16. Thermally induced electrocyclic reaction of methylenecyclopropane methylene diketone derivatives: a facile method for the synthesis of spiro[2.5]octa-3,5-dienes.

    Tang, Xiang-Ying; Wei, Yin; Shi, Min


    Thermally induced electrocyclic reactions of methylenecyclopropane (MCP) methylene diketone derivatives afford a novel method for the synthesis of spiro[2.5]octa-3,5-dienes in moderate to good yields. Applying this methodology in a one-pot manner for the reactions of MCP aldehydes with 1,3-diketones, catalyzed by l-proline, also afforded the corresponding spiro derivatives.

  17. Palladium-catalyzed cross-coupling reaction of diazo compounds and vinyl boronic acids: an approach to 1,3-diene compounds.

    Xia, Yamu; Xia, Ying; Liu, Zhen; Zhang, Yan; Wang, Jianbo


    A palladium-catalyzed oxidative cross-coupling of vinyl boronic acids and cyclic α-diazocarbonyl compounds has been reported. The reaction constitutes an efficient method for the synthesis of 1,3-diene compounds bearing a ring structure. Mechanistically, the reaction involves migratory insertion of palladium carbene as the key step.

  18. Double nucleophilic 1,2-addition of silylated dialkyl phosphites to 4-phosphono-1-aza-1,3-dienes: synthesis of gamma-phosphono-alpha-aminobisphosphonates.

    Masschelein, Kurt G R; Stevens, Christian V


    gamma-Phosphono-alpha-aminobisphosphonates were synthesized from a new class of 4-phosphono-1-aza-1,3-dienes by the addition of dialkyl trimethylsilyl phosphites to these azadienes in the presence of acid. Depending on the steric demand of the group on nitrogen, double 1,2-addition or tandem 1,4-1,2-addition occurred.

  19. Relationship between changes in peroxide value and conjugated dienes during oxidation of sunflower oils with different degree of unsaturation


    Full Text Available Peroxide value and the determination of conjugated dienes by UV absorption at 232 nm are normally applied alternatively for the evaluation of primary oxidation compounds. The objective of this study was to define the relationship between both indexes during oil oxidation in sunflower oils with different degree of unsaturation. The oils studied were conventional sunflower oil (SO and high oleic sunflower oil (HOSO. For comparative purposes, methyl linoleate, whose hydroperoxides are conjugated diene hydroperoxides, was also studied. Samples were oxidized at 40 °C in the dark. In order to accelerate oxidation at 40 °C, the natural antioxidants present in the oils were removed, and a high surface to oil volume ratio (0.8 cm-1 was applied to guarantee total air availability. Linear regressions with high correlation coefficients between peroxide values and conjugated dienes were found for the three lipid systems studied (0.9988, 0.9991 and 0.9977 for methyl linoleate, SO and HOSO, respectively. Significant differences in the slopes of the lines were found (0.0974, 0.0854 and 0.0503 for methyl linoleate, SO and HOSO, respectively, indicating the formation of non-conjugated hydroperoxides from oleic acid in the oils, even in the oxidation of SO with a high degree of unsaturation. Consequently, only peroxide value would be reliable for the evaluation of primary oxidation compounds in oils of different degree of unsaturation, unless adequate calibration lines (peroxide value versus conjugated dienes are applied.

    El índice de peróxidos y la medida de dienos conjugados mediante la extinción específica a 232 nm se utilizan alternativamente para la evaluación de compuestos primarios de oxidación en estudios de oxidación de aceites y grasas. El objetivo de este estudio fue definir las relaciones entre ambas medidas en aceites de girasol con diferente grado de in-saturación. Los aceites estudiados fueron aceite de girasol

  20. The first chiral diene-based metal-organic frameworks for highly enantioselective carbon-carbon bond formation reactions

    Sawano, Takahiro; Ji, Pengfei; McIsaac, Alexandra R.; Lin, Zekai; Abney, Carter W.; Lin, Wenbin [UC


    We have designed the first chiral diene-based metal–organic framework (MOF), E₂-MOF, and postsynthetically metalated E₂-MOF with Rh(I) complexes to afford highly active and enantioselective single-site solid catalysts for C–C bond formation reactions. Treatment of E₂-MOF with [RhCl(C₂H₄)₂]₂ led to a highly enantioselective catalyst for 1,4-additions of arylboronic acids to α,β-unsaturated ketones, whereas treatment of E₂-MOF with Rh(acac)(C₂H₄)₂ afforded a highly efficient catalyst for the asymmetric 1,2-additions of arylboronic acids to aldimines. Interestingly, E₂-MOF·Rh(acac) showed higher activity and enantioselectivity than the homogeneous control catalyst, likely due to the formation of a true single-site catalyst in the MOF. E₂-MOF·Rh(acac) was also successfully recycled and reused at least seven times without loss of yield and enantioselectivity.

  1. Acyclic Diene Metathesis (ADMET Polymerization for Precise Synthesis of Defect-Free Conjugated Polymers with Well-Defined Chain Ends

    Tahmina Haque


    Full Text Available This accounts introduces unique characteristics by adopting the acyclic diene metathesis (ADMET polymerization for synthesis of conjugated polymers, poly(arylene vinylenes, known as promising molecular electronics. The method is more suitable than the other methods in terms of atom efficiency affording defect-free, stereo-regular (exclusive trans polymers with well-defined chain ends; the resultant polymers possess better property than those prepared by the conventional methods. The chain ends (vinyl group in the resultant polymer prepared by ruthenium-carbene catalyst(s can be modified by treating with molybdenum-alkylidene complex (olefin metathesis followed by addition of various aldehyde (Wittig type cleavage, affording the end-functionalized polymers exclusively. An introduction of initiating fragment, the other conjugated segment, and one-pot synthesis of end-functionalized block copolymers, star shape polymers can be achieved by adopting this methodology.

  2. Crystal structure of 4,4-dibromo-1-(3,4-dimethoxyphenyl-2-azabuta-1,3-diene-1-carbonitrile

    Marwa Chaabene


    Full Text Available The title compound, C12H10Br2N2O2, represents an example of a planar π-conjugated 2-azabutadiene molecule, which is both an interesting starting material for further organic transformations and a potential ligand in organometallic coordination chemistry. Its metric molecular parameters are typical for the family of 2-azabuta-1,3-dienes not substituted at the (CH 3-position. In the crystal, the almost planar (r.m.s. deviation = 0.0658 Å azadiene molecules form one-dimensional double-wide ribbons through intermolecular halogen bonds (C—Br...O and C—Br...Br—C, which then stack in a slipped manner through weak C—H...Br and π–π interactions to generate a three-dimensional network.

  3. Episodes of brittle deformation within the Dien Bien Phu Fault zone, Vietnam: Evidence from K-Ar age dating of authigenic illite

    Bui, Hoang Bac; Ngo, Xuan Thanh; Khuong, The Hung; Golonka, Jan; Nguyen, Tien Dung; Song, Yungoo; Itaya, Tetsumaru; Yagi, Koshi


    Constraining the timing of fault zone origin and movement history is of fundamental geotectonic importance to understand the evolution and processes of the brittle fault structures. The authors present in this paper authigenic illite K-Ar age data from the fault gouge samples, collected from the Dien Bien Phu Fault (DBPF) in the Dien Bien province, Vietnam as well as in a major strike-slip fault zone in South-East Asia; all of which played important roles in the structural formation and geotectonic development of northwestern Vietnam. The gouge fault samples were separated into four grain-size fractions (groups, from 26 to 29 Ma and 130 Ma. The timing of the fault movements is defined at 26 ± 0.24 Ma, 29 ± 0.61 Ma, 130.1 ± 1.27 Ma and 130.7 ± 1.29 Ma. This indicates that the Dien Bien Phu Fault underwent two movements, first in the Early Cretaceous, with an age of about 130 Ma and second in the Oligocene (Paleogene), with an age of about 26-29 Ma. The ductile deformation of the DBPF terminated during the Early Cretaceous. These studies also indicate slow exhumation of the Dien Bien granitoid complex during the Cretaceous times. The Oligocene ages indicate that the DBPF had been reactivated by the SE extrusion and clock-wise rotation of the Indochina block, caused by the collision of the Indian and Eurasian plates. This tectonic event led to the DBPF brittle-sinistral movement, causing the exhumation phase along the fault. This movement period (ca. 26-29 Ma) is coexistent with 600-700 km sinistral shearing along the Red River-Ailao Shan fault. This is the first report determining the absolute age constraints of multi-activated tectonic events, affecting the Dien Bien Phu Fault using the K-Ar dating method for the gouge samples.

  4. Synthesis, crystal structure and properties of [(dien){sub 2}Mn]Ge{sub 2}S{sub 4} with mixed-valent Ge centers

    Yue, Cheng-Yang; Yuan, Zhuang-Dong; Zhang, Lu-Ge; Wang, Ya-Bai; Liu, Guo-Dong; Gong, Liao-Kuo [Key Laboratory of Inorganic Chemistry in Universities of Shandong, Department of Chemistry and Chemical Engineering, Jining University, Qufu, Shandong 273155 (China); Lei, Xiao-Wu, E-mail: [Key Laboratory of Inorganic Chemistry in Universities of Shandong, Department of Chemistry and Chemical Engineering, Jining University, Qufu, Shandong 273155 (China); State Key Laboratory of Crystal Materials, Institute of Crystal Materials, Shandong University, Jinan, Shandong 250100 (China)


    One new manganese thiogermanate, [(dien){sub 2}Mn]Ge{sub 2}S{sub 4} (dien=diethylenetriamine), was prepared under mild solvothermal conditions and structurally and spectroscopically characterized. The title compound crystallizes in the orthorhombic system, chiral space group P2{sub 1}2{sub 1}2{sub 1} (no. 19) with a=9.113(4) Å, b=12.475(5) Å, c=17.077(7) Å, V=1941.5(15) Å{sup 3} and Z=4. Its structure features a three-dimensional (3D) network composed of a one-dimensional (1D) [Ge{sub 2}S{sub 4}]{sup 2−} anionic chain and a [(dien){sub 2}Mn]{sup 2+} complex interconnected via various hydrogen bonds. The most interesting structural feature of the compound is the presence of two different oxidation states of germanium centers in the 1D [Ge{sub 2}S{sub 4}]{sup 2−} chain, which is also supported by the result of X-ray photoelectron spectroscopy measurement. The optical property of the title compound has also been studied by UV–vis spectra. - Graphical abstract: One new thiogermanate, [(dien){sub 2}Mn]Ge{sub 2}S{sub 4}, contains a one-dimensional [Ge{sub 2}S{sub 4}]{sup 2−} anionic chain with two different oxidation states of germanium centers. Display Omitted - Highlights: • One new manganese thiogermanate [(dien){sub 2}Mn]Ge{sub 2}S{sub 4} was prepared. • The compound features 1D [Ge{sub 2}S{sub 4}]{sup 2−} chain composed of [Ge{sup II}S{sub 4}] and [Ge{sup IV}S{sub 4}] tetrahedra. • The first example of inorganic–organic hybrid thiogermanates with mixed valent Ge centers.

  5. Effect of the structure of ethylene-propylene-diene-graft-polystyrene graft copolymers on morphology and mechanical properties of SAN/EPDM blends


    Full Text Available Ethylene-propylene-diene-graft-polystyrene (EPDM-g-PS copolymers were synthesized to obtain different structures of graft copolymers with different graft lengths and graft densities. The structure of synthesized EPDM-g-PS copolymers was characterized by gel permeation chromatography (GPC and by Fourier transforms infrared spectroscopy (FTIR. These presynthesized graft copolymers were added (5 phr to styrene-acrylonitrile (SAN and ethylene-propylene-diene (EPDM blends, prepared to maintain the following SAN/EPDM ratios a 95/5 and b 90/10. SAN/EPDM blends were characterized by the determination of mechanical properties (tensile strength, elongation at break while their morphology was inspected by scanning electronic microscopy, SEM. The obtained results show that various structures of EPDM-g-PS copolymers influence the miscibility in SAN/EPDM blends. Optimal concentration of side branches of graft copolymers provide the finest morphology and enhance mechanical properties.

  6. Crystal structure of trans-1,4-bis-[(tri-methyl-sil-yl)-oxy]cyclo-hexa-2,5-diene-1,4-dicarbo-nitrile.

    Glöcklhofer, Florian; Fröhlich, Johannes; Stöger, Berthold; Weil, Matthias


    The asymmetric unit of the title compound, C14H22N2O2Si2, contains one half of the mol-ecule, which is completed by inversion symmetry. The cyclo-hexa-2,5-diene ring is exactly planar and reflects the bond-length distribution of a pair of located double bonds [1.3224 (14) Å] and two pairs of single bonds [1.5121 (13) and 1.5073 (14) Å]. The tetra-hedral angle between the sp (3)-C atom and the two neighbouring sp (2)-C atoms in the cyclo-hexa-2,5-diene ring is enlarged by about 3°.

  7. Absolute configuration of falcarinol (9Z-heptadeca-1,9-diene-4,6-diyn-3-ol) from Pastinaca sativa.

    Corell, Mireia; Sheehy, Emile; Evans, Paul; Brunton, Nigel; Valverde, Juan


    Falcarinol (9Z-heptadeca-1,9-diene-4,6-diyn-3-ol; (1) is a polyacetylene commonly found in several plant families. The absolute configuration of naturally occurring 1 is not clear and contradictory results have been reported in the literature. Determination of the absolute configuration of 1 from Pastinaca sativa L. was carried out. Isolation of 95% pure 1 was performed via successive fractionation and preparative-HPLC. A racemic mixture comprised of 3R-1 and 3S-1 was synthesized in order to confirm the absolute configuration of the isolated natural product using chiral HPLC. Based on a combination of chiral HPLC and specific rotation, 1 present in P. saliva was found to have a 3R absolute configuration (i.e. (3R, 9Z)-heptadeca-1,9-diene-4,6-diyn-3-ol).

  8. A kinetics and mechanistic study of the OH and NO2 initiated oxidation of cyclohexa-1,3-diene in the gas phase

    Jenkin, M. E.; Andersen, Mads Peter Sulbæk; Hurley, M. D.


    The kinetics and products of the OH and NO2-initiated oxidation of cyclohexa-1,3-diene have been investigated at 296 K and 700 Torr using long path FTIR spectroscopy. Relative rate methods were employed using the photolysis of cyclohexa-1,3-diene/CH3ONO/NO/air mixtures to measure k(OH + cyclohexa-1......-2 produces benzene as the sole organic product, the results are consistent with abstraction channel branching ratios of (8.1 +/- 0.2)% and ( 1.5 +/- 0.4) respectively. The results also indicate that C6H7 reacts with NO2, with a relative rate coefficient k(C6H7 + NO2)/ k(C6H7 + O-2) = ( 1.8 +/- 0...

  9. B(C6F5)3: A New Class of Strong and Bulky Lewis Acid for Exo-Selective Intermolecular Diels-Alder Reactions of Unreactive Acyclic Dienes with α,β-Enals.

    Zhou, Jia-Hui; Jiang, Bing; Meng, Fei-Fan; Xu, Yun-He; Loh, Teck-Peng


    Lewis acid B(C6F5)3 catalyzed the Diels-Alder reactions of multisubstituted open-chain dienes and α,β-enals to afford the desired products with high exo-selectivities are reported. The substituent effect of the dienes and dienophiles on the product's stereoselectivity was thoroughly investigated, and it was found that most of the desired exo-Diels-Alder products could be obtained in good yields and with high exo-stereoselectivities.

  10. Structure Revision of (22E)-Ergosta-7,22-diene-3β,5α,6β,9α,14α- pentol from the Spores of the Medicinal Mushroom Ganoderma lucidum.

    Yaoita, Yasunori; Machida, Koichi


    Careful reexamination of the published ¹H and ¹³C NMR spectral data of (22E)-ergosta-7,22-diene-3β,5α,6β,9α,14α-pentol (1), isolated from the spores of the medicinal mushroom Ganoderma lucidum, indicates that, in reality, the compound is (22E)-ergosta-7,22-diene-3β,5α,6β,9α,14β-pentol (5).

  11. A Convenient and Efficient Route to 1,4-Bis(heteroaryl)buta-1,3-diene and 4-Heteroarylbut-1-en-3-yne from 1,4-Dichlorobut-2-yne

    ZHANG Xiao-Ming; WU Guo-Qiang; CHEN Wan-Zhi


    A convenient and practical route to functionalized conjugated 1,3-enynes and 1,3-dienes is described.1,4-Bis(heteroaryl)-1,3-diene and 1-heteroarylbut-1-en-3-yne derivatives were prepared from 1,4-dichloro-2-buty'ne and corresponding N-heteroarenes such as imidazole, pyrrole, pyrazole and indole derivatives in the presence of bases in good to high yields.

  12. Conformation Analysis and Comparison of Epristeride(17β-N-t-Butylcarboxamide-androst-3,5-diene-3-carboxylic Acid) and Its Analogs

    YAO Li-xin


    Conformations of Epristeride(17-β-N-t-butylcarboxamide-androst-3,5-diene-3-carboxylic acid) and its analogs were analyzed with the random search method and compared by means of the methods for steroid conformers, Connolly surfaces, dihedral angles, and molecular accessibility probes with protons, hydroxyl and methyl groups contained simultaneously. Analog d is different from others, which is in accordance with the preliminary clinical trial results under double blind conditions.

  13. Regio-, Diastereo-, and Enantioselective Nitroso-Diels-Alder Reaction of 1,3-Diene-1-carbamates Catalyzed by Chiral Phosphoric Acids.

    Pous, Jonathan; Courant, Thibaut; Bernadat, Guillaume; Iorga, Bogdan I; Blanchard, Florent; Masson, Géraldine


    Chiral phosphoric acid-catalyzed asymmetric nitroso-Diels-Alder reaction of nitrosoarenes with carbamate-dienes afforded cis-3,6-disubstituted dihydro-1,2-oxazines in high yields with excellent regio-, diastereo-, and enantioselectivities. Interestingly, we observed that the catalyst is able not only to control the enantioselectivity but also to reverse the regioselectivity of the noncatalyzed nitroso-Diels-Alder reaction. The regiochemistry reversal and asynchronous concerted mechanism were confirmed by DFT calculations.

  14. An efficient approach to functionalized benzo[a]xanthones through reactions of 2-methyl-3-(1-alkynyl)chromones with electron-deficient chromone-fused dienes.

    Gong, Jian; Xie, Fuchun; Chen, Hong; Hu, Youhong


    An efficient tandem process was developed to synthesize diversified benzo[a]xanthones from 2-methyl-3-(1-alkynyl)chromones with electron-deficient chromone-fused dienes. This unusual reaction, involving multiple steps and not requiring the use of transition metal catalysts or an inert atmosphere, results in the formation of three new C-C bonds and one C-O bond.

  15. Facial Selectivity in the Nucleophilic Additions of endo-Tricyclo[5.2.1.O2.6]deca-2(6),8-dien-3-one


    Nucleophilic additions to endo-tricyclo[]deca-2(6),8-dien-3-one 4 are described.Experimental results show high preference for exo-facial attack to the enone moiety of tricyclodecadienone. Steric hindrance is the main kinetically controlling factor in the nucleophilic reaction. The shielding effect and the stabilizing effect of the norbornene double bond favor the exo-facial attack also.

  16. Synthesis and biochemical studies of 7 alpha-substituted androsta-1,4-diene-3,17-diones as enzyme-activated irreversible inhibitors of aromatase.

    Ebrahimian, S; Chen, H H; Brueggemeier, R W


    Several 7 alpha-thiosubstituted derivatives of androstenedione have demonstrated effective inhibition of aromatase, the cytochrome P450 enzyme complex responsible for the biosynthesis of estrogens. Introduction of an additional double bond in the A ring resulted in 7 alpha-(4'-amino)phenylthioandrosta-1,4-diene-3,17-dione (7 alpha-APTADD), a potent inhibitor that inactivated aromatase by an enzyme-catalyzed process. Additional 7 alpha-thiosubstituted androsta-1,4-diene-3,17-dione derivatives were designed to further examine enzyme-catalyzed inactivation. Two halogenated and one unsubstituted 7 alpha-phenylthioandrosta-1,4-diene-3,17-diones were synthesized via an acid-catalyzed conjugate Michael addition of substituted thiophenols with androsta-1,4,6-triene-3,17-dione. Two 7 alpha-naphthylthioandrosta-1,4-diene-3,17-diones were synthesized via either acid-catalyzed or based-catalyzed conjugate Michael addition of substituted thionaphthols with androsta-1,4,6-triene-3,17-dione. These agents were evaluated for aromatase inhibitory activity in the human placental microsomal preparation. Under initial velocity assay conditions of low product formation, the inhibitors demonstrated potent inhibition of aromatase, with apparent Ki's ranging from 12 to 27 nM. Furthermore, these compounds produced time-dependent, first-order inactivation of aromatase in the presence of NADPH, whereas no aromatase inactivation was observed in the absence of NADPH. This enzyme-activated irreversible inhibition, also referred to as mechanism-based inhibition, can be prevented by the substrate androstenedione. Thus, the apparent Ki values for these inhibitors are consistent with earlier studies on 7 alpha-substituted competitive inhibitors that indicate bulky substituents can be accommodated at the 7 alpha-position.(ABSTRACT TRUNCATED AT 250 WORDS)

  17. Phosphine-catalyzed [4+1] annulation of 1,3-(aza)dienes with maleimides: highly efficient construction of azaspiro[4.4]nonenes.

    Yang, Mei; Wang, Tianyi; Cao, Shixuan; He, Zhengjie


    Phosphine-catalyzed [4+1] annulation of electron-deficient 1,3-dienes or 1,3-azadienes with maleimides has been successfully developed under very mild conditions, providing a convenient and highly efficient method for constructing 2-azaspiro[4.4]nonenes and 1,7-diazaspiro[4.4]nonenes. This reaction represents the first example of [4+1] cyclization between electron-deficient 4π-conjugated systems and non-allylic phosphorus ylides.

  18. Diene Hydroacylation from the Alcohol or Aldehyde Oxidation Level via Ruthenium Catalyzed C-C Bond Forming Transfer Hydrogenation: Synthesis of β,γ-Unsaturated Ketones

    Shibahara, Fumitoshi; Bower, John F.; Krische, Michael J.


    Under the conditions of ruthenium catalyzed transfer hydrogenation, isoprene couples to benzylic and aliphatic alcohols 1a–1g to deliver β,γ-unsaturated ketones 3a–3g in good to excellent isolated yields. Under identical conditions, aldehydes 2a–2g couple to isoprene to provide an identical set of β,γ-unsaturated ketones 3a–3g in good to excellent isolated yields. As demonstrated by the coupling of butadiene, myrcene and 1,2-dimethylbutadiene to representative alcohols 1b, 1c and 1e, diverse acyclic dienes participate in transfer hydrogenative coupling to form β,γ-unsaturated ketones. In all cases, complete branch-regioselectivity is observed and, with the exception of adduct 3j, isomerization to the conjugated enone is not detected. Thus, formal intermolecular diene hydroacylation is achieved from the alcohol or aldehyde oxidation level. In earlier studies employing a related ruthenium catalyst, acyclic dienes were coupled to carbonyl partners from the alcohol or aldehyde oxidation level to furnish branched homoallylic alcohols. Thus, under transfer hydrogenative coupling conditions, all oxidations levels of substrate (alcohol or aldehyde) and product (homoallyl alcohol or β,γ-unsaturated ketone) are accessible. PMID:18841895

  19. Effect of three 2-allyl-p-mentha-6,8-dien-2-ols on inhibition of mild steel corrosion in 1 M HCl

    S. Kharchouf


    Full Text Available 2-Allyl-p-mentha-6,8-dien-2-ols P1−P3 synthesized from carvone P are tested as corrosion inhibitors of steel in 1 M HCl using weight loss measurements, potentiodynamic polarisation and impedance spectroscopy (EIS methods. The addition of 2-allyl-p-mentha-6,8-dien-2-ols reduced the corrosion rate. Potentiodynamic polarisation studies clearly reveal that the presence of inhibitors does not change the mechanism of hydrogen evolution and that they act essentially as cathodic inhibitors. 2-Allyl-p-mentha-6,8-dien-2-ols tested adsorb on the steel surface according to Langmuir isotherm. From the adsorption isotherm some thermodynamic data for the adsorption process are calculated and discussed. EIS measurements show the increase of the charge-transfer resistance with the inhibitor concentration. The highest inhibition efficiency (92% is obtained for P1 at 3 g/L. The corrosion rate decreases with the rise of temperature. The corresponding activation energies are determined.

  20. Dependence of Adhesion Properties on Blend Ratio of Ethylene-Propylene-Diene Rubber/Standard Malaysian Rubber Blend Adhesive

    B. T. Poh


    Full Text Available Viscosity, tack and, peel and shear strengths of ethylene-propylene-diene rubber (EPDM/standard Malaysian rubber (SMR L blend adhesive were studied using various blend ratios of the two rubbers, ranging from 0 to 100% EPDM. Coumarone-indene resin, toluene, and poly(ethylene terephthalate (PET were used as the tackifier, solvent, and coating substrate, respectively. The tackifier content was fixed at 40 parts per hundred parts of rubber (phr. A SHEEN hand coater was used to coat the adhesive on PET film at four coating thicknesses, that is, 30, 60, 90, and 120 µm. The viscosity and adhesion properties were determined by a Brookfield viscometer and a Lloyd Adhesion Tester, respectively. Results show that the viscosity, loop tacks and peel strength of blend adhesives decrease gradually with increasing % EPDM. This observation is attributed to dilution effect and lowering in wettability and compatibility. Shear strength, however, passes through a maximum at 20–40% EPDM blend ratio, an observation which is ascribed to culmination of cohesive strength at the optimum EPDM blend ratio. Increasing coating thickness increases the adhesion properties in all blend ratios in this study.

  1. The Curing Characteristics and Mechanical Properties of Wood Sawdust/Carbon Black Filled Ethylene Propylene Diene Rubber Composites

    Prachid SARAMOLEE


    Full Text Available In this research work, ethylene propylene diene rubber (EPDM composites were prepared by incorporating wood sawdust and carbon black on a 2 roll mill. The effect of wood sawdust content on the curing characteristics and mechanical properties of EPDM composites were studied. When the size of wood sawdust was fixed, it was found that wood sawdust content had no effect on scorch time. The cure time, minimum torque and maximum torque increased with increasing wood sawdust content. Increasing the wood sawdust content tended to increase the hardness of the composites, but the tensile strength and elongation at break decreased, heat ageing resistance and ozone resistance slightly decreased. Moreover, the types and concentrations of coupling agents were compared between silane Si69 and epoxidized natural rubber, ENR-50 (50 % mol epoxide groups on the mechanical properties of EPDM composites. It was found that a silane Si69 concentration of 2.0 wt % of wood sawdust improved the mechanical properties of the EPDM composites but ENR-50 was not able to improve interfacial adhesion between the wood sawdust and EPDM matrix.

  2. Filled Ethylene-propylene Diene Terpolymer Elastomer as ThermalInsulator for Case-bonded Solid Rocket Motors

    C. M. Bhuvaneswari


    Full Text Available Ethylene-propylene diene terpolymer (EPDM-based insulation system is being globallyused for case-bonded solid rocket motors. A study was undertaken using EPDM as base polymer,blended with hypalon and liquid EPDM and filled with fibrous and non-fibrous fillers. Theseformulations were evaluated as rocket motor insulation system. The basic objective of the studywas to develop an insulation system based on EPDM for case-bonded applications. A series ofrocket motor insulator compositions based on EPDM, filled with particulate and fibrous fillerslike precipitated silica, fumed silica, aramid, and carbon fibres have been studied for mechanical,rheological, thermal, and interface properties. Compositions based on particulate fillers wereoptimised for the filler content. Comparatively, fumed silica was found to be superior as fillerin terms of mechanical and interface properties. Addition of fibrous filler (5 parts improved thepeel strength, and reduced the thermal conductivity and erosion rate. All the compositions wereevaluated for sulphur and peroxide curing. Superior mechanical properties were achieved forsulphur-cured products, whereas peroxide-cured products exhibited an excellent ageing resistance.Rocket motors were insulated with optimised composition and propellant cast, and the motorswere evaluated by conducting static test in end-burning mode.Defence Science Journal, 2008, 58(1, pp.94-102, DOI :

  3. Effects of carbon blacks with various structures on vulcanization and reinforcement of filled ethylene-propylene-diene rubber


    Full Text Available The effects of carbon blacks on vulcanization and mechanical properties of filled ethylene-propylene-diene rubber (EPDM are investigated, by comparing with five types of rubber-grade carbon blacks. Curing kinetics is studied by rheometer and the results indicate that the curing characteristics are influenced by combination of surface area of carbon black and sulphur content on the filler surface, because the former one enhances the physical cross-linking and the latter one introduces the additional chemical cross-linking. Both the degree of cross-linking and cure rate increase with increasing surface area and sulphur content, whereas the optimum cure time and scorch time decrease. The reinforcing nature of the carbon black is assessed from mechanical measurements. It is suggested that the surface area of carbon blacks strongly affects the physical properties of EPDM/carbon black composites. Conductive carbon black (N472 can be used as desirable reinforcing filler due to the higher degree of cross-linking of EPDM with N472 than other EPDM/carbon black composites. The morphology and distribution of particles are studied by using scanning electron microscope. The sound reinforcing ability of N472 is also supported by scanning electron microscope due to the notable dispersibility of N472 within EPDM matrix. N472 ensures the EPDM/N472 composite the most conductive sample among the five composites.

  4. Assessment of the role of in situ generated (E)-2,4-diene-valproic acid in the toxicity of valproic acid and (E)-2-ene-valproic acid in sandwich-cultured rat hepatocytes

    Surendradoss, Jayakumar; Chang, Thomas K.H.; Abbott, Frank S., E-mail:


    Valproic acid (VPA) undergoes cytochrome P450-mediated desaturation to form 4-ene-VPA, which subsequently yields (E)-2,4-diene-VPA by β-oxidation. Another biotransformation pathway involves β-oxidation of VPA to form (E)-2-ene-VPA, which also generates (E)-2,4-diene-VPA by cytochrome P450-mediated desaturation. Although the synthetic form of (E)-2,4-diene-VPA is more hepatotoxic than VPA as shown in various experimental models, there is no conclusive evidence to implicate the in situ generated (E)-2,4-diene-VPA in VPA hepatotoxicity. The present study investigated the effects of modulating the in situ formation of (E)-2,4-diene-VPA on markers of oxidative stress (formation of 2′,7′-dichlorofluorescein; DCF), steatosis (accumulation of BODIPY 558/568 C{sub 12}), necrosis (release of lactate dehydrogenase; LDH), and on cellular total glutathione (GSH) levels in sandwich-cultured rat hepatocytes treated with VPA or (E)-2-ene-VPA. Treatment with either of these chemicals alone increased each of the toxicity endpoints. In VPA-treated hepatocytes, (E)-2,4-diene-VPA was detected only at trace levels, even after phenobarbital (PB) pretreatment and there was no effect on the toxicity of VPA. Furthermore, pretreatment with a cytochrome P450 enzyme inhibitor, 1-aminobenzotriazole (1-ABT), did not influence the extent of VPA toxicity in both PB-pretreated and vehicle-pretreated hepatocytes. However, in (E)-2-ene-VPA-treated hepatocytes, PB pretreatment greatly enhanced the levels of (E)-2,4-diene-VPA and this was accompanied by a further enhancement of the effects of (E)-2-ene-VPA on DCF formation, BODIPY accumulation, LDH release, and GSH depletion. Pretreatment with 1-ABT reduced the concentrations of (E)-2,4-diene-VPA and the extent of (E)-2-ene-VPA toxicity; however, this occurred in PB-pretreated hepatocytes, but not in control hepatocytes. In conclusion, in situ generated (E)-2,4-diene-VPA is not responsible for the hepatocyte toxicity of VPA, whereas it

  5. The Labdane Ent-3-Acetoxy-Labda-8(17), 13-Dien-15-Oic Decreases Blood Pressure In Hypertensive Rats

    Simplicio, Janaina A.; Simão, Marilia R.; Ambrosio, Sergio R.; Tirapelli, Carlos R.


    Background Labdane-type diterpenes induce lower blood pressure via relaxation of vascular smooth muscle; however, there are no studies describing the effects of labdanes in hypertensive rats. Objective The present study was designed to investigate the cardiovascular actions of the labdane-type diterpene ent-3-acetoxy-labda-8(17), 13-dien-15-oic acid (labda-15-oic acid) in two-kidney 1 clip (2K-1C) renal hypertension. Methods Vascular reactivity experiments were performed in aortic rings isolated from 2K-1C and normotensive (2K) male Wistar rats. Nitrate/nitrite (NOx) measurement was performed in aortas by colorimetric assay. Blood pressure measurements were performed in conscious rats. Results Labda-15-oic acid (0.1-300 µmol/l) and forskolin (0.1 nmol/l - 1 µmol/l) relaxed endothelium-intact and endothelium-denuded aortas from both 2K-1C and 2K rats. Labda-15-oic acid was more effective at inducing relaxation in endothelium-intact aortas from 2K pre-contracted with phenylephrine when compared to the endothelium-denuded ones. Forskolin was more potent than labda-15-oic acid at inducing vascular relaxation in arteries from both 2K and 2K-1C rats. Labda-15-oic acid-induced increase in NOx levels was lower in arteries from 2K-1C rats when compared to 2K rats. Intravenous administration of labda-15-oic acid (0.3-3 mg/kg) or forskolin (0.1-1 mg/kg) induced hypotension in conscious 2K-1C and 2K rats. Conclusion The present findings show that labda-15-oic acid induces vascular relaxation and hypotension in hypertensive rats. PMID:27096521

  6. Highly toughened polypropylene/ethylene–propylene-diene monomer/zinc dimethacrylate ternary blends prepared via peroxide-induced dynamic vulcanization

    Chen, Yukun, E-mail: [The Key Laboratory of Polymer Processing Engineering, Ministry of Education, South China University of Technology, Guangzhou 510640 (China); School of Mechanical and Automotive Engineering, South China University of Technology, Guangzhou 510640 (China); Xu, Chuanhui [College of Material Science and Engineering, South China University of Technology, Guangzhou 510640 (China); Cao, Liming [The Key Laboratory of Polymer Processing Engineering, Ministry of Education, South China University of Technology, Guangzhou 510640 (China); School of Mechanical and Automotive Engineering, South China University of Technology, Guangzhou 510640 (China); Cao, Xiaodong [College of Material Science and Engineering, South China University of Technology, Guangzhou 510640 (China)


    Polypropylene (PP)/ethylene–propylene-diene monomer (EPDM)/zinc dimethacrylate (ZDMA) blends with remarkable toughness and extensibility were successfully prepared via peroxide dynamical vulcanization. A unique structure with the EPDM particles surrounded by a transition zone containing numerous polymerized ZDMA (PZDMA) nano-particles was observed for the first time by using transmission electron microscopy (TEM) examination, which contributed to the dramatically increase of Izod impact strength. Dynamic mechanical analysis (DMA) confirmed that the possible PZDMA graft products resulted from peroxide dynamical vulcanization improved the compatibility between EPDM and PP phases. The specific morphology of the PP/EPDM/ZDMA blends indicated that ZDMA can lead to size reduction and good distribution uniformity of the crosslinked rubber particles and the increase of adhesion between PP matrix and EPDM phases during deformation. The synergic effect of the increase in the effective volume of the EPDM phase, the improved compatibility and adhesion between EPDM and PP phases and the deformation of those fine rubber particles is believed to result in the remarkable high toughness and extensibility of the PP/EPDM/ZDMA blends. Particularly for the PP/EPDM ratio of 70/30, the PP/EPDM/ZDMA (70/30/9, w/w/w) ternary blends with the Izod impact strength nearly 2 times higher than PP/EPDM (70/30, w/w) binary blends and 15–20 times higher than PP are achieved; besides, the elongation at break of PP/EPDM/ZDMA ternary blends is 4–5 times higher than that of PP/EPDM binary blends. - Highlights: ► ZDMA largely toughen peroxide dynamically vulcanized PP/EPDM blend. ► PZDMA graft products improved the compatibility and adhesion between EPDM and PP. ► Size reduction and good distribution uniformity of crosslinked rubber particles.

  7. The effect of pyrolytic carbon black prepared from junked tires on the properties of ethylene-propylene-diene copolymers (EPDM


    Full Text Available Pyrolytic carbon black (PCB made from used tires was used in ethylene-propylene-diene copolymers (EPDM. The microstructure of PCB was characterized by scanning electron microscopy (SEM. PCB was compounded with EPDM to prepare EPDM vulcanizates. The effects of PCB on the processing properties of EPDM compounds and the mechanical properties of vulcanizates were investigated and compared with other traditional fillers such as semi-reinforcing furnace black (N774, light calcium carbonate (CaCO3 and thermal black (N990. At the same time, the rheological behavior of EPDM compounds filled with different fillers was characterized by capillary rheometrics. The SEM photos showed that the particle shape was quiet different from that of CaCO3 and N990, it was similar to that of N774. The primary particle size was smaller than that of N774, but the aggregate size of PCB was larger than that of N774. The effect of PCB on the processing properties of EPDM compounds was similar to that of other fillers. Among the four fillers, PCB imparted EPDM compounds with higher Mooney viscosity. With the increase of filler content, the scorch time and optimum curing time of EPDM compounds changed little. The reinforcing effect of PCB was similar to that of N990, but inferior to that of N774. With the increase of PCB content, tensile strength, tear strength, and modulus at 100% elongation of EPDM vulcanizates increased significantly. When EPDM was filled with 50 phr PCB, the tear strength of EPDM vulcanizates increased by 3 times, compared with that of EPDM gum vulcanizates. The appearance of EPDM extrudate filled with PCB was coarser than that of other fillers.

  8. The Labdane Ent-3-Acetoxy-Labda-8(17), 13-Dien-15-Oic Decreases Blood Pressure In Hypertensive Rats

    Simplicio, Janaina A. [Programa de Pós-Graduação em Farmacologia - Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo (USP), Ribeirão Preto, SP (Brazil); Departamento de Enfermagem Psiquiátrica e Ciências Humanas - Laboratório de Farmacologia - Escola de Enfermagem de Ribeirão Preto (USP), Ribeirão Preto, SP (Brazil); Simão, Marilia R.; Ambrosio, Sergio R. [Núcleo de Pesquisa em Ciências e Tecnologia - Universidade de Franca (UNIFRAN), Franca, SP (Brazil); Tirapelli, Carlos R., E-mail: [Departamento de Enfermagem Psiquiátrica e Ciências Humanas - Laboratório de Farmacologia - Escola de Enfermagem de Ribeirão Preto (USP), Ribeirão Preto, SP (Brazil)


    Labdane-type diterpenes induce lower blood pressure via relaxation of vascular smooth muscle; however, there are no studies describing the effects of labdanes in hypertensive rats. The present study was designed to investigate the cardiovascular actions of the labdane-type diterpene ent-3-acetoxy-labda-8(17), 13-dien-15-oic acid (labda-15-oic acid) in two-kidney 1 clip (2K-1C) renal hypertension. Vascular reactivity experiments were performed in aortic rings isolated from 2K-1C and normotensive (2K) male Wistar rats. Nitrate/nitrite (NOx) measurement was performed in aortas by colorimetric assay. Blood pressure measurements were performed in conscious rats. Labda-15-oic acid (0.1-300 µmol/l) and forskolin (0.1 nmol/l - 1 µmol/l) relaxed endothelium-intact and endothelium-denuded aortas from both 2K-1C and 2K rats. Labda-15-oic acid was more effective at inducing relaxation in endothelium-intact aortas from 2K pre-contracted with phenylephrine when compared to the endothelium-denuded ones. Forskolin was more potent than labda-15-oic acid at inducing vascular relaxation in arteries from both 2K and 2K-1C rats. Labda-15-oic acid-induced increase in NOx levels was lower in arteries from 2K-1C rats when compared to 2K rats. Intravenous administration of labda-15-oic acid (0.3-3 mg/kg) or forskolin (0.1-1 mg/kg) induced hypotension in conscious 2K-1C and 2K rats. The present findings show that labda-15-oic acid induces vascular relaxation and hypotension in hypertensive rats.

  9. The Presence of Amorpha-4, 11-Diene Synthase, a Key Enzyme in Artemisinin Production in Ten Artemisia Species

    GA. Garoosi


    Full Text Available Background and the purpose of the study: Artemisinin is one of the most effective medicine against malaria, which is produced naturally by Artemisia annua in low yield. It is produced in a metabolic pathway, in which several genes and gene products are involved. One of the key genes in this pathway is am1, which encodes amorpha-4, 11-diene synthase (ADS, a key enzyme in artemisinin biosynthesis pathway. The aim of this study was to determine the presence of this gene in ten Artemisia species in order to increase the yield of production of Artemisinin. Methods : The experiments were carried out using PCR. Specific primers were designed based on the published am1 gene sequence obtained from A. annua (NCBI, accession number AF327527. Results: The amplification of this gene by the specific primers was considered as a positive sign for the potentiality of artemisinin production. Since the entire am1 gene was not amplified in any of the 10 species used, four parts of the gene, essential in ADS enzyme function, corresponding to a pair site of Arg10-Pro12 in the first 100 amino acids, b aspartate rich motif (DDXXD, c active site final lid and d active site including farnesyl diphosphate (FDP ionization sites and catalytic site in the ADS enzyme, were investigated. Major conclusion: The sequence corresponding to ADS active site was amplified only in A. annua, A. aucheri and A. chamaemelifolia. The negative results obtained with other species could be due to some sequence alteration, such as point mutations or INDELs. We propose A. aucheri and A. chamaemelifolia as two potential candidate species for further characterization, breeding and transferring am1 gene for artemisinin overproduction.

  10. Absolute rate constants for the reaction of NO3 radicals with a series of dienes at 295 K

    Ellermann, T.; Nielsen, O.J.; Skov, H.


    The rate constants for the reaction of NO3 radicals with a series of 7 dienes, 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, trans-1,3-pentadiene, cis-1,3-pentadiene, trans,trans-2,4-hexadiene, and 1,3-cyclohexadiene, were measured at 295 K and at a total pressure of 1 atm. The rate consta...... were obtained using the absolute technique of pulse radiolysis combined with kinetic UV-VIS spectroscopy. The results are discussed in terms of reactivity trends and previous literature data....

  11. Crystal structure of dimethyl 3,4,5,6-tetra-phenyl-cyclo-hexa-3,5-diene-1,2-di-carboxyl-ate.

    Greenberg, Fred H; Nazarenko, Alexander Y


    In the title compound, C34H28O4, the cyclo-hexa-diene ring has a screw-boat conformation with a torsion angle between the double bonds being on average ca 15° [15.2 (3) and -15.3 (3) in the two independent mol-ecules]. All four phenyl rings in both mol-ecules are arranged in a propeller-like conformation. The two mol-ecules exhibit S,R- and R,S- chirality, respectively, and are connected via C-H⋯O inter-molecular inter-actions. In turn, these weakly bound dimers form the mol-ecular crystal.

  12. Dependence of Adhesion Property of Epoxidized Natural Rubber (ENR 25)/Ethylene-Propylene-Diene Rubber Blend Adhesives Crosslinked by Benzoyl Peroxide

    B. T. Poh; Y. Y. Teh


    The loop tack, peel strength, and shear strength of crosslinked epoxidized natural rubber (ENR 25)/ethylene-propylene-diene rubber (EPDM) blend adhesives were investigated. Coumarone-indene resin, toluene, and benzoyl peroxide were used as the tackifier, solvent, and crosslinking agent, respectively, throughout the experiment. The adhesive was coated on a polyethylene terephthalate (PET) substrate using a SHEEN hand coater at 60 μm and 120 μm coating thickness. It was cured at 80°C for 30 min...

  13. Investigation of surface modifications in ethylene propylene diene monomer (EPDM) rubber due to tracking under a.c. and d.c. voltages

    R Sarathi; Uma Maheswar Rao


    In the present work, tracking phenomena has been studied with the ethylene propylene diene monomer (EPDM) material under the a.c. and d.c. voltages, with ammonium chloride/acid rain solution as the contaminant. It is noticed that the tracking time depends on the conductivity and flow rate of the contaminant. The physico-chemical analyses viz. wide angle X-ray diffraction (WAXD), thermo-gravimetric differential thermal analysis (TG-DTA) and the differential scanning calorimetry (DSC) studies, were carried out and it was concluded that the tracking process is a surface degradation process. The tracking time is different for a.c. and d.c. voltages.

  14. Synthesis and Characterization of a Reduced Molybdenum(Ⅴ) Phosphate, (H3dien)2(H2dien)2[NaMo12O24(OH)6-(H2PO4)(HPO4)5(PO4)2]·nH2O(n= 10.92)

    CAO Xue-Gong; LIN Bi-Zhou; GENG Feng; LI Xiao-Li; XIAO Zi-Jing


    A new reduced molybdenum(Ⅴ) phosphate (H3dien)2(H2dien)2[NaMo12O24 (OH)6 (H2PO4)(HPO4)5(PO4)2]·nH2O(n= 10.92,dien = diethylenetriamine) has been synthesized under hydrothermal conditions and characterized by elemental analyses, IR and X-ray diffraction. C16H96.84MO12N12NaO72.92P8 (Mr = 3046.73) crystallizes in the monoclinic system, space group P21/c with a = 13.3575(18), b = 21.907(3), c = 15.654(2) A, β= 110.22(2)°, V= 4298.4(10) (A)3, Dc = 2.354 g/cm3, Z = 2, μ(MoKα) = 1.966 mm-1, F(000) = 2990.4, the final R = 0.0357 and wR = 0.1086 for 8739 observed reflections with Ⅰ> 2σ(Ⅰ). It consists of sandwich-shaped cluster anions [Na{Mo6P4}2]10- held together into a three-dimensional supramolecular framework through intermolecular hydrogen-bonding contacts. A probe reaction of the oxidation of acetaldehyde with H2O2 showed that this compound has high catalytic activity in the reaction.

  15. Influence of the nature of surface-active substances on rheology of high-filled pastelike compositions on a base on liquid diene rubber and disperse filler

    Alexander B. Surovtcev


    Full Text Available Results of researches on reception of pastelike high-filled compositions and estimation of their rheological properties with use cone – plate rheometer are presented. Liquid diene rubber with end hydroxyl groups (as binding, surfaceactive substance (PEAHENS and disperse filler are entered into structure of compositions. The estimation of sedimentation firmness of compositions and their fluidity in the range of pressure of shift 1 – 30 кPа and temperatures from 30 to 50°С is executed. By results of an estimation of influence of concentration dependence of PEAHENS on a viscosity indicator it is shown that its introduction in a pastelike composition at level 0.5 mas. % is expedient. For considered in work low polar liquid diene rubber more effective decrease in viscosity of a pastelike composition provide polyoxypropylene, especially on the average an interval of pressure of shift which basically can be used in practice. Slightly concede them titanorganic derivatives of oligomer polyoxypropylene. The greatest effect of decrease in viscosity for compositions will reach at use oligomer polyoxypropylene with molecular weight 480, in this case viscosity of a composition is at level of 10 Pa ⋅ s for rather wide interval of pressure of shift.

  16. An orthorhombic polymorph of N1,N4-diphenyl-3,6-bis(phenyliminocyclohexa-1,4-diene-1,4-diamine

    Keiji Ohno


    Full Text Available A new orthorhombic polymorph of the title compound, C30H24N4, with a density of 1.315 Mg m−3, has been obtained. The molecule is centrosymmetric with the centroid of the cyclohexa-1,4-diene ring located on an inversion center. The two unique benzene rings are almost perpendicular to each other [dihedral angle = 86.70 (6°] and are oriented at dihedral angles of 30.79 (5 and 68.07 (5° with respect to the central cyclohexadiene ring. In the crystal, π–π stacking is observed between the central cyclohexa-1,4-diene-1,4-diamine unit and a phenyl ring of a neighboring molecule [centroid–centroid distance = 3.7043 (7 Å]. The crystal structure of the triclinic polymorph [Ohno et al. (2014. Acta Cryst. E70, o303–o304] showed chains running along the b-axis direction through weak C—H...π interactions.

  17. Cytoprotection of Human Endothelial Cells Against Oxidative Stress by 1-[2-cyano-3,12-dioxooleana-1,9(11)-dien-28-oyl]imidazole (CDDO-Im): Application of Systems Biology to Understand the Mechanism of Action


    oyl] imidazole (CDDO-Im): Application of systems biology to understand the mechanism of action Xinyu Wang a,n, James A. Bynumb,c, Solomon Stavchansky...enzyme. To further improve this cytoprotective effect, we studied a synthetic triterpenoid, 1-[2-cyano-3,12-dioxooleana-1,9(11)-dien-28-oyl] imidazole ...2-cyano-3,12-dioxooleana-1,9(11)-dien-28-oyl] imidazole (CDDO-Im): Application of systems biology to understand the mechanism of action 5a. CONTRACT

  18. Regioselective Cleavage of Electron-Rich Double Bonds in Dienes to Carbonyl Compounds with [Fe(OTf)2(mix-BPBP)] and a Combination of H2O2 and NaIO4

    Spannring, Peter; Yazerski, Vital A.; Chen, Jianming; Otte, Matthias; Weckhuysen, Bert M.; Bruijnincx, Pieter C A; Klein Gebbink, Robertus J M


    A method for the regioselective transformation of dienes to carbonyl compounds has been developed. Electron-rich olefins react selectively to yield valuable aldehydes and ketones. The method is based on the catalyst [Fe(OTf)2(mix-BPBP)] with an oxidant combination of H2O2 (1.0 equiv.) and NaIO4 (1.5

  19. The Synthesis of π,n-Complexes of 1-Thio-1,3-dienes with Chromium Group Metals. The Inner-Sphere Hydrophosphorylation of α-Enethiones

    Kuramshin A.I.


    Full Text Available New 1-thio-1,3-diene complexes of chromium(0, molybdenum(0, and tungsten(0 with the biden-tate bonding of unsaturated ligand to the metal’s core via the π-system of the C=C bond and sulfur lone electron pair of heterodiene are obtained. Quantum-chemical calculations reveal geometry, electron structure, and formation free energies of these complexes, as well as factors governing the coordination mode. Hydrophosphorylation of the complexes begins from the attack of H-dialkylphosphonate towards the thiocarbonyl group; the generated organometallic α-mercaptophosphonates subsequently undergo the mercaptophosphonate-thiolphospate and thiolphosphate-thionphosphate rearrangements with organ-ophosphorus compounds remaining bound to the metal’s core.

  20. Investigation of Mechanical Properties of Magneto-Rheological Ethylene Propylene Diene Monomer and Natural Rubber Type Synthetic Rubbers for Both Isotropic and Anisotropic Situations

    Uğur Mazlum


    Full Text Available Magneto-rheological (MR materials are in a smart material class that has the rheological properties to be quickly and reversibly controlled with the external magnetic field applications. Considering the technological developments the rubber-like smart materials has had a more functional usage area with magneto- rheological effect. This study investigates the axial mechanical properties of magneto-rheological Ethylene Propylene Diene Monomer (EPDM and Natural Rubber (NR type synthetic rubbers for isotropic and anisotropic situations. Also, these composite materials were built by means of hot press systems as either isotropic or anisotropic using magnetic field application after addition of ferromagnetic powders. The influence of magnetic field was investigated. In this study, NR rubber was found to be more susceptible in terms of smart material properties unlike EPDM synthetic rubber.

  1. Calvyn se vierde diens, die doktore-amp, en artikel 18 van die kerkorde van Dordrecht 1618 en 1619: ’n Kritiese refleksie

    Andries L. du Plooy


    Full Text Available Die artikel fokus op Calvyn se besondere rol in die formulering van artikels 2 en 18 van die kerkorde van Dordrecht 1618 en 1619. Hierdie kerkorde word steeds deur ’n groot aantal gereformeerde kerke in die wêreld aanvaar en gebruik.Onderwerpe en probleme wat aangeraak word, sluit vrae in soos die volgende: Wie is verantwoordelik vir die onderrig van Teologie? Is die tradisie geldig dat daar naas die drie dienste van Woordbedienaar, ouderling en diaken ook ’n vierde diens bestaan, naamlik dié van doktor in die Teologie? Kan hierdie tradisie, wat hoofsaaklik op die standpunte van Bucer en Calvyn berus, met die gegewens in die Bybel versoen word?Besondere aandag word aan die volgende aspekte gegee:•\tHistoriese gegewens oor doktor in die Teologie met besondere verwysing na die standpunte en invloed van Calvyn.•\t’n Kritiese evaluering van die begronding van die vierde diens op die Bybel.•\tDie verhouding tussen teologiese opleiding in die konteks van die kerk en/of ’n universiteit.•\tBesondere aandag word gegee aan die situasie in die Gereformeerde Kerke in Suid-Afrika ten opsigte van die funksionering van hierdie vierde diens.Van die belangrikste konklusies wat gemaak word, is die volgende: die kerk het deur die eeue ’n besondere waardering en respek gehad vir die taak en funksie van die doktore in die Teologie. Dit het inderdaad tot groot seën van die kerke gedien. Calvyn se standpunte het dikwels tot verwarring aanleiding gegee, maar andersyds ook bygedra tot die erkenning van die belangrike funksie of taak wat hierdie vierde diens kerklik verrig. Net so vervul die doktore in die Teologie ’n besondere wetenskaplike rol aan teologiese fakulteite van universiteite.Calvin’s fourth office, the doctor ministry, and article 18 of the church order of Dordrecht 1618 and 1619: A critical reflection. This article focuses on Calvin’s special role in the ecclesiastical formulation of articles 2 and 18 in the church order of

  2. Enantio- and Stereoselective Cyclopolymerization of Hexa-1,5-diene Catalyzed by Zirconium Complexes Possessing Optically Active Bis(phenolato) Ligands.

    Nakata, Norio; Watanabe, Takanori; Toda, Tomoyuki; Ishii, Akihiko


    Enantio- and stereoselective cyclopolymerization of hexa-1,5-diene was achieved by enantiomerically pure dichloro zirconium(IV) pre-catalysts 2 possessing chiral [OSSO]-type bis(phenolate) ligands (-)-1 and (+)-1 in combination with dried methylaluminoxane (dMAO) as an activator. The corresponding activities were recorded with quite high values up to 1,960 g mmol(2)(-1) h(-1) , which are extremely larger than those of the related complexes. The microstructure analysis for the PMCPs furnished by pre-catalysts (Λ,S,S)-2 and (Δ,R,R)-2 showed good isotacticity factors (α = 75-78%) and relatively high proportions of trans-cyclopentane rings (σ = 14-21%). These enantiomeric PMCPs exhibited large specific optical rotations ([α]D = +28 to +32° from (Λ,S,S)-2, -26 to -34° from (Δ,R,R)-2).

  3. Crystal structure of dimethyl 2,5-bis-[(di-phen-oxy-phosphor-yl)-oxy]cyclo-hexa-1,4-diene-1,4-di-carboxyl-ate.

    Gao, Lei; Ma, Zongshan; Yan, Hong


    In the title compound, C34H30O12P2, which was synthesized via the esterification of dimethyl 2,5-dioxo-1,4-cyclo-hexa-nedi-carboxyl-ate with diphenyl chloro-phosphate, the mol-ecule has crystallographic inversion symmetry. The dihedral angles between the plane of the cyclo-hexa-1,4-diene ring and those of the two benzene rings of the substituent phosphate groups are 41.0 (1) and 89.5 (1)°, while that with the ester group is 3.1 (3)°. In the crystal, only weak inter-molecular C-H⋯O hydrogen bonds are present.

  4. Crystal structure of chlorido­bis­[(1,2,5,6-η)-cyclo­octa-1,5-diene]iridium(I)

    Rahman, A. K. Fazlur; Wilklow-Marnell, Miles; Brennessel, William W.; Jones, William D.


    The title complex, [IrCl(C8H12)2], was synthesized directly from the reaction of IrCl3·3H2O with a large excess of cod (cod = cyclo­octa-1,5-diene) in alcoholic solvent. Large yellow needles were obtained by the slow cooling of a hot solution. Based on the positions of the chloride ligand and the mid-points of the four C=C bonds, the mol­ecule adopts a five-coordinate geometry that is midway between square pyramidal and trigonal bipyramidal. The material crystallizes in the ortho­rhom­bic space group Pbca with one mol­ecule per asymmetric unit in a general position and shows no significant inter­molecular inter­actions. Individual mol­ecules are aligned along [010], and these rows form a pseudo-hexa­gonal packing arrangement. PMID:28217358

  5. Résultats à long terme de l'évidement pétro-mastoïdien en technique ouverte

    Castrillón, Rodrigo


    Introduction: Cette étude évalue les résultats anatomiques et fonctionnels à long terme de l'évidement pétro-mastoïdien en technique ouverte (EPMto). Méthode: Sont analysés les résultats de 259 opérations de première intention avec tympano-ossiculoplastie dans le même temps opératoire, réalisées entre 1974 et 1998 chez des patients souffrant d'oto-mastoïdite ou d'otite chronique cholestéatomateuse. Résultats: A long terme, la cavité était propre dans 95% des cas et l'audition préservée ou amé...

  6. Résultats à long terme de l'évidement pétro-mastoïdien en technique ouverte

    Castrillón, Rodrigo; Guyot, Jean-Philippe


    Introduction: Cette étude évalue les résultats anatomiques et fonctionnels à long terme de l'évidement pétro-mastoïdien en technique ouverte (EPMto). Méthode: Sont analysés les résultats de 259 opérations de première intention avec tympano-ossiculoplastie dans le même temps opératoire, réalisées entre 1974 et 1998 chez des patients souffrant d'oto-mastoïdite ou d'otite chronique cholestéatomateuse. Résultats: A long terme, la cavité était propre dans 95% des cas et l'audition préservée ou am...

  7. The Conjugation Stress of Ligand via Metal Core as the Cause of Changes in the Reactivity of Coordinated 1-Hetero-1,3-Dienes

    A.I. Kuramshin


    Full Text Available Using quantum-chemical calculations carried out for interpretation of the experimentally discovered reactivity of 1-hetero-1,3-dienes that are mono- and bidentally coordinated with the transition metal core, we have revealed that the difference in hydrophosphorylation directions of the free organic molecule and the same molecule involved in the coordination sphere of the transition metal can be explained by either weakening or complete loss of conjugation between the C=C and C=X fragments as a result of coordination. In the case of monodentate coordination of heterodiene with the transition metal according to the eta(2(C,C-type, the conjugation weakening is suggested to be maximum for the transition metal characterized by the minimum electronegativity, which predetermines the increased contribution of the metalcyclopropane resonance structure into the general bonding mode. Organometallic compounds having the heterodiene ligand bidentally coordinated demonstrate the conjugation weakening parallel to the metal radius.

  8. ([2.2.2]Cryptand-κ(6)O)potassium (η(4)-cyclo-octa-diene)bis-(η(2)-pyrene)cobaltate(1-) pentane hemisolvate.

    Brennessel, William W; Ellis, John E


    The cation, anion, and solvent in the title compound, [K(C(18)H(36)N(2)O(6))][Co(C(8)H(12))(C(16)H(10))(2)]·0.5C(5)H(12), are well separated. The pentane solvent mol-ecules are found in channels along [100] and were modeled as disordered over crystallographic inversion centers. Using the mid-points of the coordinated olefins, the angle between the C(py)/C(py)-Co-C(py)/C(py) and the C(cod)/C(cod)-Co-C(cod)/C(cod) planes (py is pyrene and cod is cyclo-octa-diene) is 67.6 (2)°. Thus, the overall geometry of the coordination sphere around cobalt is best described as distorted tetra-hedral.

  9. Synthesis and Characterization of Pyridino(1,4-Η-cyclohexa-1,3-dieneDerivatives of Iron Tricarbonyl Complexes

    T. I. Odiaka


    Full Text Available In this synthesis, we have been able to show that, the addition of x- substituted pyridines, (X = H, 2- Me, 3- Me 4- Me, 4-NH2 and 4-N(CH32 to the dienyl ring of the organometallic cation, [(Fe(CO3 (1-5- η-2-Me0C3H6]BF4 and [(Fe(CO3(1-5-η-C6H7]BF4 gives ionic substituted diene products, (X C5H4-C6H6Y (Fe(CO3] BF4,Y=H or 2-MeO. The reaction takes place at ordinary room temperature. The resulting products were isolated and characterized.

  10. Synthesis and cytotoxic activities of novel 2-(1,5-bis(aryl penta-1,4-dien-2-yl benzo[d]thiazol derivatives

    Betül Şahin


    Full Text Available Novel 2-(1,5-bis(arylpenta-1,4-dien-2-ylbenzo[d]thiazol (5a,b and 2-(((1S,2S,E-2-(benzo[d]thiazol-2-yl-1,5-di-arylpent-4-en-1-ylthioaniline (6a,b derivatives were obtained by addition of 2-aminobenzothiol to bis-benzylidinecyclobutanones (3a,b. The structures of the obtained compounds were characterized using the spectroscopic methods (NMR, IR, Elemental Analysis. Compounds 5a,b showed cytotoxic activities against C6 (Rat Brain tumor cells and HeLa (human uterus carcinoma in vitro. ©2016 ACG Publications. All rights reserved.

  11. 钴(Ⅲ)-胺配合物模板导向合成新型草酸盐化合物[Co(dien)2][NaCO2(C2O4)4]·H20%Template-directed Synthesis of a Novel Oxalate Compound[Co (dien) 2][NaCo2 ( C2O4 ) 4]Using Co ( Ⅲ ) Complex as Template

    潘勤鹤; 陈强; 韩义德; 胡同亮; 卜显和


    以Co(dien)2·Cl3为模板剂,在水热条件下导向合成出新型草酸盐化合物[Co(dien)2]·[NaC02(C2O4).].H2O,并通过X射线单晶结构分析、元素分析、ICP以及X射线粉末衍射分析对该化合物的结构进行了表征.结果表明,该化合物结构属于单斜晶系,C2/c空间群,晶胞参数a=1.3805(3)nm,b=1.3017(3)nm,c=1.5913(3)nm,β=104.41(3)°,V=2.7695(10)nm3,Z=4.在该化合物的结构中,C02+先与草酸基团相互交替连接形成一个常见的链状结构基元[Co(C2O4)2]2n-/n,这些链状结构基元进一步被分布于链间的Na+连接成三维开放骨架结构[NaCO2(C2O4)4]3n/n.金属配合物离子Co(dien)3+/2存在于孔道中起模板剂的作用.%Using Co(dien)2· Cl3 as the template, a new oxalate compound, [Co (dien)2]·[NaCo2(C2O4)], was synthesized under hydrothermal condition. Its structure was determined by singlecrystal X-ray diffraction analysis, elemental analyses, ICP and X-ray powder diffraction. It crystallizes in monoclinic system space group C2/c with a = 1. 3805 ( 3 ) nm, b = 1. 3017 ( 3 ) nm, c = 1. 5913 ( 3 ) nm, β = 104. 41 (3) °, V = 2. 7695 (10) nm3, Z = 8. In this structure, the Co2 + ions first link to oxalate ligands to form a chain-like building unit[Co( C2O4 )2]2n-n, then those chain-like building units are further connected by Na + cations, which are dispersed between the chains, to form a three dimensional oxalate open-framework of [NaCo2 (C2O4 )4]3n-n . The complex cations Co(dien)3+2 are encapsulated inside the channels as template.

  12. Comparative in vitro metabolism of the 'designer' steroid estra-4,9-diene-3,17-dione between the equine, canine and human: identification of target metabolites for use in sports doping control.

    Scarth, James P; Clarke, Adam D; Teale, Philip; Pearce, Clive M


    Effective detection of the abuse of androgenic-anabolic steroids in human and animal sports often requires knowledge of the drug's metabolism in order to target appropriate urinary metabolites. 'Designer' steroids are problematic since it is difficult to obtain ethical approval for in vivo metabolism studies due to a lack of a toxicological profile. In this study, the in vitro metabolism of estra-4,9-diene-3,17-dione is reported for the first time. This is also the first study comparing the metabolism of a designer steroid in the three major species subject to sport's doping control; namely the equine, canine and human. In order to allow the retrospective analysis of sample testing data, the use of a high-resolution (HR) accurate-mass Thermo LTQ-Orbitrap LC-MS instrument was employed for metabolite identification of underivatised sample extracts. The full scan HR-LC-MS Orbitrap data was complimented by several further experiments targeted at elucidating more detailed structural information for the most abundant metabolites. These included; HR-LC-MS/MS of the underivatised metabolites, functional group selective chemical derivatisation followed by full scan HR-LC-MS, enzyme inhibition experiments and full scan electron ionization GC-MS analysis of methoxyamine-trimethylsilyl derivatives. The major metabolite detected in all species, and therefore the most suitable candidate for screening of estra-4,9-diene-3,17-dione abuse, was proposed to be an isomer of 17-hydroxy-estra-4,9-dien-3-one. Less significant metabolic pathways in all species included hydroxylation and reduction followed by hydroxylation. Reductive metabolism in the canine was less significant than in the other two species, while the equine was unique in producing a di-reduced metabolite (proposed to be an isomer of estra-4,9-diene-3,17-diol) and also relatively large quantities of d-ring hydroxy and hydroxy-reduced metabolites.

  13. A Novel Stereoselective Synthesis of (1Z,3E)-2-Phenyl(or p-Tolyl)sulfonyl-substituted 1,3-Dienes via Palladium Catalyzed Cross-coupling Reactions of (E)-α-lodovinyl Sulfones

    HU Rong-Hu; CHEN Gui-Qin; CAI Ming-Zhong


    (E)-α-Stannylvinyl phenyl(or p-tolyl)sulfones underwent an iododestannylation reaction to afford (E)-α-iodovinyl phenyl(or p-tolyl)sulfones 1,which reacted with (E)-alkenylzirconium(Ⅳ) complexes 2 produced in situ by hydrozirconation of terminal alkynes in the presence of a Pd(PPh3)4 catalyst to afford stereoselectively (1Z,3E)-2phenyl(or p-tolyl)sulfonyl-substituted 1,3-dienes 3 in good yields.

  14. Expedient synthesis of 17α,21-dihydroxy-9β,11β-epoxy-16α-methylpregna-1,4-diene-3,20-dione 21-acetate from prednisolone utilising a novel Mattox rearrangement.

    Hulcoop, David G; Shapland, Peter D P


    A six step transformation of prednisolone to 17α,21-dihydroxy-9β,11β-epoxy-16α-amethylpregna-1,4-diene-3,20-dione 21-acetate has been achieved in 13% unoptimised yield. Novel conditions for effecting a Mattox rearrangement and double dehydration of prednisolone were identified. Enhanced knowledge on the oxidation of silyl Δ(19,20)-enol ethers and structural factors that impact the success of the oxidation are also presented.

  15. An ortho-rhom-bic polymorph of N (1),N (4)-diphenyl-3,6-bis-(phenyl-imino)-cyclo-hexa-1,4-diene-1,4-di-amine.

    Ohno, Keiji; Fujihara, Takashi; Nagasawa, Akira


    A new ortho-rhom-bic polymorph of the title compound, C30H24N4, with a density of 1.315 Mg m(-3), has been obtained. The mol-ecule is centrosymmetric with the centroid of the cyclo-hexa-1,4-diene ring located on an inversion center. The two unique benzene rings are almost perpendicular to each other [dihedral angle = 86.70 (6)°] and are oriented at dihedral angles of 30.79 (5) and 68.07 (5)° with respect to the central cyclo-hexa-diene ring. In the crystal, π-π stacking is observed between the central cyclo-hexa-1,4-diene-1,4-di-amine unit and a phenyl ring of a neighboring mol-ecule [centroid-centroid distance = 3.7043 (7) Å]. The crystal structure of the triclinic polymorph [Ohno et al. (2014 ▶). Acta Cryst. E70, o303-o304] showed chains running along the b-axis direction through weak C-H⋯π inter-actions.

  16. Preparative isolation and purification of cuminaldehyde and p-menta-1,4-dien-7-al from the essential oil of Cuminum cyminum L. by high-speed counter-current chromatography.

    Chen, Qinqin; Hu, Xuefang; Li, Jingming; Liu, Ping; Yang, Yang; Ni, Yuanying


    High-speed counter-current chromatography (HSCCC) technique in semi-preparative scale was successfully used in isolation and purification of cuminaldehyde and p-menta-1,4-dien-7-al from the essential oil of Cuminum cyminum L. by using a two-phase solvent system composed of n-hexane-methanol-water (5:4:1, v/v/v). The targeted compounds were isolated, collected, purified by HSCCC in the head-tail mode, and then analyzed by gas chromatography (GC). A total of 12.72 ± 0.22 mg of cuminaldehyde and 10.61 ± 0.27 mg of p-menta-1,4-dien-7-al were obtained from 50 mg of the essential oil of C. cyminum L. in less than 6 h, with purities of 95.42% and 97.21%, respectively. In addition to GC-EI/MS, the identity of the cuminaldehyde was further confirmed with the retention time using the method of standard addition, while, the structural identification of p-menta-1,4-dien-7-al was performed with GC-EI/MS, (1)H NMR and (1)H-(1)H COSY.

  17. Low-loaded Pd/{alpha}-Al{sub 2}O{sub 3} catalysts: Influence of metal particle morphology on hydrogenation of buta-1,3-diene and hydrogenation and isomerization of but-1-ene

    Goetz, J.; Touroude, R. [Universite Louis Pasteur, Strasbourg (France); Volpe, M.A. [Planta Piloto de Ingeneria Quimica, Bahia Blanca (Argentina)


    Buta-1,3-diene hydrogenation and but-1-ene hydrogenation and isomerization were studied on low-loaded Pd/{alpha}-Al{sub 2}O{sub 3} catalysts (0.1-0.3 wt.%) prepared from palladium acetylacetonate (Pd(C{sub 5}H{sub 7}O{sub 2}){sub 2}). Deuterium tracer study, hydrogen chemisorption, transmission electron microscopy, and X-ray photoelectron spectroscopy analysis were used to establish the relationships between metal-support interactions, particle shapes, and buta-1,3-diene and but-1-ene hydrogenation and isomerization mechanisms. It was found that the hydrogenation reaction rates (turnover frequencies) are similar for buta-1,3-diene and but-1-ene, but 10 times lower for the 0.1% Pd catalyst compared to the 0.3% Pd catalyst. However, the 0.1% Pd catalyst has a high activity for the isomerization reaction which leads to 98% selectivity in isomers for the but-1-ene reaction. This unusual specific activity is explained considering that the 0.1% Pd catalyst contains flat particles in strong interaction with the support, as was deduced from several characterization methods, while the 0.3% Pd catalyst has more rugged bulk type particles after H{sub 2} treatments because they are not interacting with the support. 33 refs., 7 figs., 5 tabs.

  18. Dual Regulation of Cell Death and Cell Survival upon induction of cellular stress by Isopimara-7,15-Dien-19-Oic Acid in cervical cancer, Hela cells In vitro

    Nadiah eAbu


    Full Text Available The fritarillia imperialis is an ornamental flower that can be found in various parts of the world including Iraq, Afghanistan, Pakistan and the Himalayas. The use of this plant as traditional remedy is widely known. This study aims to unveil the anti-cancer potentials of Isopimara-7,15-Dien-19-Oic Acid, extracted from the bulbs of Fritillaria imperialis in cervical cancer cell line, HeLa cells. Flow cytometry analysis of cell death, gene expression analysis via cDNA microarray and protein array were performed. Based on the results, Isopimara-7,15-Dien-19-Oic acid simultaneously induced cell death and promoted cell survival. The execution of apoptosis was apparent based on the flow cytometry results and regulation of both pro and anti-apoptotic genes. Additionally, the regulation of anti-oxidant genes were up-regulated especially thioredoxin, glutathione and superoxide dismutase- related genes. Moreover, the treatment also induced the activation of pro-survival heat shock proteins. Collectively, Isopimara-7,15-Dien-19-Oic Acid managed to induce cellular stress in HeLa cells and activate several anti- and pro survival pathways.

  19. Solvothermal syntheses, crystal structures, and thermal stability of two new thioantimonates(III) using complex transition metal cations as structure directing agents: the layered compound [Ni(dien) 2]Sb 4S 7·H 2O and the three-dimensional compound [Ni(dien) 2] 3Sb 12S 21·H 2O

    Stähler, Ralph; Näther, Christian; Bensch, Wolfgang


    The two new thioantimonates(III) [Ni(dien) 2]Sb 4S 7·H 2O ( I) and [Ni(dien) 2] 3Sb 12S 21·H 2O ( II) were prepared under solvothermal conditions using elemental Ni, Sb, S and an aqueous solution of diethylenetriamine (dien) as solvent. Compound I crystallizes in the monoclinic space group P2 1/ c, a=9.603(2) Å, b=16.137(3) Å, c=17.272(4) Å, β=91.68(3)°, V=2675.3(9) Å 3, Z=4 and compound II crystallizes in the monoclinic space group C2/ c with a=12.6072(7) Å, b=14.9967(7) Å, c=41.445(2) Å, β=95.371(6)°, V=7801.4(7) Å 3, Z=4. The two-dimensional ∞2[Sb 4S 72-] anion in I is composed of two SbS 3 trigonal pyramids and two SbS 4 units. The SbS 3 units are connected via one corner to form a Sb 2S 5 unit and the two SbS 4 moieties share a common edge building a trans-Sb 2S 6 unit. The Sb 2S 5 and trans-Sb 2S 6 units have one common S atom to form the layered ∞2[Sb 4S 72-] anion. Within the layers Sb 2S 2, Sb 4S 4 and Sb 8S 8 heterorings are found with the mer-[Ni(dien) 2] 2+ residing above and below the large pores. In compound II the ∞3[Sb 12S 216-] anion is composed of four SbS 3 pyramids and two SbS 4 units. The condensation of the different primary units yields Sb xS x rings with x=2,3,4,8, and 32. The largest ring consists of 64 atoms (Sb 32S 32) and the pores with an ellipsoidal shape are oriented parallel to the [110] direction. To the best of our knowledge this is the largest Sb xS x heteroring found in thioantimonates(III) so far. The cations are located above and below the large ring or within the plane of the ring. Nearly rectangular channels are running along [101] which have dimensions of about 7.6·13.5 Å. The channels are occupied by the water molecule and by the ligands pointing into the channels. The thermal behavior of the compounds was investigated using differential thermoanalysis (DTA), thermogravimetry (TG) and mass spectroscopy (MS) measurements. Upon heating decomposition of the compounds starts at Tonset=235°C (I) and Tonset

  20. Thermal aging of interfacial polymer chains in ethylene-propylene-diene terpolymer/aluminum hydroxide composites: solid-state NMR study.

    Gabrielle, Brice; Lorthioir, Cédric; Lauprêtre, Françoise


    The possible influence of micrometric-size filler particles on the thermo-oxidative degradation behavior of the polymer chains at polymer/filler interfaces is still an open question. In this study, a cross-linked ethylene-propylene-diene (EPDM) terpolymer filled by aluminum trihydrate (ATH) particles is investigated using (1)H solid-state NMR. The time evolution of the EPDM network microstructure under thermal aging at 80 °C is monitored as a function of the exposure time and compared to that of an unfilled EPDM network displaying a similar initial structure. While nearly no variations of the topology are observed on the neat EPDM network over 5 days at 80 °C, a significant amount of chain scission phenomena are evidenced in EPDM/ATH. A specific surface effect induced by ATH on the thermodegradative properties of the polymer chains located in their vicinity is thus pointed out. Close to the filler particles, a higher amount of chain scissions are detected, and the characteristic length scale related to these interfacial regions displaying a significant thermo-oxidation process is determined as a function of the aging time.

  1. Dependence of Adhesion Property of Epoxidized Natural Rubber (ENR 25/Ethylene-Propylene-Diene Rubber Blend Adhesives Crosslinked by Benzoyl Peroxide

    B. T. Poh


    Full Text Available The loop tack, peel strength, and shear strength of crosslinked epoxidized natural rubber (ENR 25/ethylene-propylene-diene rubber (EPDM blend adhesives were investigated. Coumarone-indene resin, toluene, and benzoyl peroxide were used as the tackifier, solvent, and crosslinking agent, respectively, throughout the experiment. The adhesive was coated on a polyethylene terephthalate (PET substrate using a SHEEN hand coater at 60 μm and 120 μm coating thickness. It was cured at 80°C for 30 minutes before testing on a Lloyd adhesion tester operating at testing rates from 10 to 60 cm min−1. Results show that loop tack and peel strength of the ENR 25/EPDM adhesive pass through a maximum value at 2 parts per hundred parts of rubber (phr of benzoyl peroxide content. This observation is attributed to the increase in crosslinking which enhances the cohesive strength of the adhesive. Further addition of the crosslinking agent decreases the tack and peel strength due to the decrease in wettability of the over-crosslinked adhesive. Shear strength, however, increases steadily with benzoyl peroxide content, an observation which is associated with the steady increase in the cohesive strength. The adhesion properties increase with increasing coating thickness and testing rate.

  2. Prostaglandin-induced radioprotection of murine intestinal crypts and villi by a PGE diene analog (SC-44932) and a PGI analog (Iloprost)

    Hanson, Wayne R.; Collins, Paul W.

    The aminothiols exemplified by WR-2721 are effective radioprotectors; however, their toxicity associated with hypotension, nausea, and emesis has limited their development for applications in medicine or in hazardous radiation environments. There is a need for new radioprotectors that have fewer toxic side effects when given alone or combined with reduced amounts of thiols. A variety of prostaglandins (PGs) have been shown to be radioprotective agents and some appear to have fewer toxic side effects than the aminothiols. Iloprost, a stable PGI, analog protects the clonogenic epithelial cells of intestinal crypts but does not protect epithelial cells of the villi. In contrast, an E-series omega chain diene analog designated SC-44932 protects epithelial cells of both crypts and villi. When the two are combined, protection of the crypts is additive and the villi are protected to the same degree as when SC-44932 is given alone. Since radioprotection for some PGs has been shown to be dependent upon receptors, we suggest that the pattern of radioprotection seen with these two analogs depend on the location of the respective receptors or on the ability of differentiated villus cells to respond to PGs. By studying different analogs, we hope to identify mechanisms associated with PG-induced radioprotection and to identify the most protective PG analogs for applications of radioprotection.

  3. Cloning, E. coli Expression and Molecular Analysis of Amorpha-4,11-Diene Synthase from a High-Yield Strain of Artemisia annua L.

    Zhen-Qiu Li; Yan Liu; Ben-Ye Liu; Hong Wang; He-Chun Ye; Guo-Feng Li


    Increasing demand of artemisinin in the treatment of malaria has placed substantial stress on the total artemisinin supplies world-wide, so more attention has been paid to increasing the content of artemisinin in the Artemisia annua L. plant. In this study, amorpha-4, 11-diene synthase (ADS) cDNA (ads1) and genomics gene (gads1) were cloned from a high-yield A. annua strain 001. The activity of ADS1 was confirmed by heterogeneous overexpression of ads1 and in vitro enzymatic incubation. Reverse transcript-polymerase chain reaction results demonstrated that ads1 expressed in leaves, flowers and young stems, but not in roots. This organ-specific expression pattern of ads1 is consistent with that of artemisinin accumulation in the plant. The gads1 has a complex organization including seven exons and six introns, and belongs to class Ⅲ terpene synthase. DNA gel blotting revealed that the ADS gene has at least four copies in the genome of strain 001. The higher copy numbers might be one of the reasons for its high artemisinin content.

  4. Chemical aromatization of 19-hydroxyandrosta-1,4-diene-3,17-dione with acid or alkaline: elimination of the 19-hydroxymethyl group as formaldehyde.

    Numazawa, Mitsuteru; Yamashita, Kouwa; Kimura, Nao; Takahashi, Madoka


    In order to determine whether or not a 19-hydroxymethyl group of 19-hydroxyandrosta-1,4-diene-3,17-dione (2, 19-hydroxy ADD), an intermediate of aromatase-catalyzed estrone formation from ADD, a suicide substrate of aromatase, is eliminated as formaldehyde, we examine chemical nature of removal of the 19-hydroxymethyl group. 19-acetate 3 and 19-tert-butyldimethylsiloxy compound 4 are known to convert rapidly to estrone with treatment of NaOH or n-Bu4NF. Since compound 2 was unstable and unobtainable under these conditions, compounds 3 and 4 as equivalents to compound 2 were used in this study. The acetate 3 with 5 mol/l HCl in acetone and 10% KOH in MeOH along with the silyl ether 4 with 5 mol/l HCl in acetone and 1 mol/l n-Bu4NF in THF gave formaldehyde and estrone in which a ratio of the aldehyde to estrone was near 1. This result indicates that the 19-hydroxymethyl groups of compound 3 and 4 are eliminated as formaldehyde along with estrone derived from the steroid skeleton under the acid or base treatment. The findings suggest that a single hydroxylation at the 19 carbon of ADD (1) would be, chemically, all that was required for estrone formation.


    Jayesh J. Ahire


    Full Text Available Cholesterol biotransformation by Lactobacillus helveticus CD6 was observed in minimal medium supplemented with 3 mM cholesterol when grown for 120 h at 37 °C. Its gas chromatography-mass spectrometry (GC-MS showed production of cholesta-4, 6-dien-3-ol and cholest-5-en-3-ol (3.beta with 12 U ∕mg cholesterol oxidase-like enzyme activity. The cholesterol assimilation was evaluated at varied concentrations of bile salt in MRS medium. The cell survival and cholesterol assimilation was found to be adversely affected in presence of bile salt. Microscopic studies revealed changed cell morphology when grown with cholesterol. The cell adhesion properties like autoaggregation, microbial adhesion to solvents where found to be affected by cholesterol. The 7.49 % cell adhesion to ethyl acetate indicates the decrease in electron accepting properties of cell surface, while 9 % decrease in xylene adhesion and 13 % decrease in autoaggregation was observed which would be helpful in cholesterol lowering when supplemented in the form of probiotic preparation.

  6. Photobehavior of copper(I) compounds. 4. Role of the triplet state of (arylphosphine)copper(I) complexes in the photosensitized isomerization dienes

    Liaw, B.; Orchard, S.W.; Kutal, C.


    Photoisomerization of cis- and trans-piperylene can be sensitized with high quantum efficiency by Cu(diphos)BH/sub 4/ (diphos is 1,2-bis(diphenylphosphino)ethane) and Cu(prophos)BH/sub 4/ (prophos is 1,3-bis(diphenylphosphino)propane). Sensitization is accompanied by quenching of the emissive /sup 3/(/sigma/-a/sub /pi//) excited state in each copper(I) complex, and the two processes occur with identical Stern-Volmer kinetics. Measurements of the trans/cis diene ratio at the photostationary state can be used to estimate the triplet-state energy as 60-61 kcal for Cu(diphos)BH/sub 4/ and > 61 kcal for Cu(prophos)BH/sub 4/; additional evidence suggests that 66-67 kcal is a reasonable value for the latter complex. Collectively, the results support the assignment of triplet-triplet energy transfer as the primary mechanism for sensitization and quenching in these systems. This mechanism also can accommodate earlier reports that Cu(diphos)BH/sub 4/ and Cu(prophos)BH/sub 4/ sensitize the valence isomerization of norbornadiene to quadricyclene with markedly different quantum efficiencies. 17 refs., 6 figs., 2 tabs.

  7. Abcès thyroïdien révélant un basedow: à propos d’un cas et revue de la littérature

    Chenguir, Meriem; Souldi, Hajar; Loufad, Fatima Zahra; Rouadi, Sami; Abada, Reda; Roubal, Mohamed; Mahtar, Mohamed


    L’abcès thyroïdien est une entité clinique très rare. Elle représente 0,1% des pathologies chirurgicales de la thyroïde. Les caractéristiques anatomique et physiologique de la glande lui procurent une résistance vis-à-vis des agents pathogènes. Les infections à Streptococcies et Staphylococcus sont les plus fréquentes. La tuberculose reste rarement rapportée dans la littérature. La survenue de l’infection sur goitre toxique est exceptionnelle. Les auteurs rapportent un cas rare d’abcès thyroïdien révélant un goitre toxique chez un jeune de 22 ans. Il s’est présenté aux urgences ORL pour une tuméfaction cervicale antérieure, légèrement latéralisée à gauche, mobile à la déglutition, associée à des hémoptysies, signes de dysthyroïdie, fièvre et sueurs nocturnes. La TDM cervicale a montré une masse occupant le lobe thyroïdien gauche de contenu liquidien mesurant 2 cm, avec un liquide purulent à la cytoponction. L’examen cyto-bactériologique a mis en évidence un Staphylococcus avec recherche de BK positive. Une radiographie thoracique a été demandée montrant un foyer alvéolaire pulmonaire apical droit. L’étude cytobactériologique des crachats ont isolé le bacille de koch. Le bilan biologique thyroïdien était en faveur d’un Basedow. La prise en charge était médicale comprenait une tri-antibiothérapie par voie parentérale, anti-bacillaire et anti-thyroïdien de synthèse avec bonne évolution. Le diagnostic de la tuberculose doit être évoqué devant toute abcédation thyroïdienne avec un tableau clinique peu bruyant. Il s’agit le plus souvent d’une dissémination hématogène à partir d’un autre foyer de primo-infection surtout pulmonaire. Le traitement est basé sur les anti-bacillaires associé parfois à la chirurgie. PMID:27795799

  8. Wound healing activity of ent-kaura-9(11),16-dien-19-oic acid isolated from Wedelia trilobata (L.) leaves.

    Balekar, Neelam; Nakpheng, Titpawan; Katkam, Nadpi Gangadhar; Srichana, Teerapol


    Wedelia trilobata (L.) Hitchc (Asteraceae) has been used in traditional medicine in the Caribbean and Central America for stubborn wounds, sores, swelling, arthritic painful joints. The present study was carried out to derive bioactive compounds from ethanolic extracts of W. trilobata (L.) leaves that could influence wound healing. W. trilobata leaves extract were subjected to bioassay-guided fractionation. The five fractions (WEA1-A, B, C, D, and E) obtained were tested for antimicrobial activity. Out of the five fractions only the fraction (WEA1-B) containing ent-kaura-9(11),16-dien-19-oic acid showed promising antibacterial activity with MIC value of 15.62μg/ml against S. aureus and 7.81μg/ml against S. epidermidis. It was then further assessed for its possible activity on fibroblasts by measuring their percentage cell viability and on oxidative stress induced by hydrogen peroxide. WEA1-B (2.5-0.08μg/ml) produced an increase in the percentage viability of mouse fibroblast L929 cells from 97 to 117% and protection of the fibroblast L929 cells against oxidative stress induced by hydrogen peroxide (94-80%). The present study provides some scientific evidence for the traditional use of W. trilobata in the management of wound healing due to a combination of antimicrobial, stimulation of fibroblast growth and protection of the cells from hydrogen peroxide-induced injury, all of which could play some role in its effect on tissue repair. Copyright © 2012 Elsevier GmbH. All rights reserved.

  9. Protection of HepG2 cells against acrolein toxicity by 2-cyano-3,12-dioxooleana-1,9-dien-28-imidazolide via glutathione-mediated mechanism.

    Shah, Halley; Speen, Adam M; Saunders, Christina; Brooke, Elizabeth A S; Nallasamy, Palanisamy; Zhu, Hong; Li, Y Robert; Jia, Zhenquan


    Acrolein is an environmental toxicant, mainly found in smoke released from incomplete combustion of organic matter. Several studies showed that exposure to acrolein can lead to liver damage. The mechanisms involved in acrolein-induced hepatocellular toxicity, however, are not completely understood. This study examined the cytotoxic mechanisms of acrolein on HepG2 cells. Acrolein at pathophysiological concentrations was shown to cause apoptotic cell death and an increase in levels of protein carbonyl and thiobarbituric acid reactive acid substances. Acrolein also rapidly depleted intracellular glutathione (GSH), GSH-linked glutathione-S-transferases, and aldose reductase, three critical cellular defenses that detoxify reactive aldehydes. Results further showed that depletion of cellular GSH by acrolein preceded the loss of cell viability. To further determine the role of cellular GSH in acrolein-mediated cytotoxicity, buthionine sulfoximine (BSO) was used to inhibit cellular GSH biosynthesis. It was observed that depletion of cellular GSH by BSO led to a marked potentiation of acrolein-mediated cytotoxicity in HepG2 cells. To further assess the contribution of these events to acrolein-induced cytotoxicity, triterpenoid compound 2-cyano-3,12-dioxooleana-1,9-dien-28-imidazolide (CDDO-Im) was used for induction of GSH. Induction of GSH by CDDO-Im afforded cytoprotection against acrolein toxicity in HepG2 cells. Furthermore, BSO significantly inhibited CDDO-Im-mediated induction in cellular GSH levels and also reversed cytoprotective effects of CDDO-Im in HepG2 cells. These results suggest that GSH is a predominant mechanism underlying acrolein-induced cytotoxicity as well as CDDO-Im-mediated cytoprotection. This study may provide understanding on the molecular action of acrolein which may be important to develop novel strategies for the prevention of acrolein-mediated toxicity.

  10. Administration d’anti-inflammatoires non stéroïdiens aux enfants ayant des antécédents de sibilance

    Sih, Kendra; Goldman, Ran D.


    Résumé Question Un enfant qui fréquente ma clinique s’est récemment fait une entorse à la cheville et il éprouve de la douleur et de la difficulté à supporter son poids sur la jambe affectée. Sa mère lui donne de l’acétaminophène parce qu’on lui a dit de ne jamais utiliser d’anti-inflammatoires non stéroïdiens (AINS) en raison de son asthme contrôlé par pharmacologie. L’asthme chez un enfant est-il une contre-indication à l’administration d’AINS? La maladie respiratoire exacerbée par les AINS existe-t-elle comme entité réelle? Réponse Les AINS sont des médicaments analgésiques et antipyrétiques efficaces. La maladie respiratoire exacerbée par des AINS a été décrite chez des adultes ayant certains facteurs de prédisposition, mais n’a pas été clairement identifiée chez un grand nombre d’enfants. Les AINS peuvent donc être recommandés aux enfants ayant une sibilance connue qui n’ont pas d’antécédents de maladie respiratoire déclenchée par des AINS. PMID:27521406

  11. Effect of storage time and conditions on the diene valepotriates content of the extract of Valeriana glechomifolia obtained by supercritical carbon dioxide.

    Müller, Liz Girardi; de Andrade Salles, Luisa; Sakamoto, Satchie; Stein, Ana Cristina; Cargnin, Simone Tasca; Cassel, Eduardo; Vargas, Rubem Figueiró; Rates, Stela Maris Kuze; von Poser, Gilsane Lino


    Valepotriates (epoxy iridoid esters) represent an important group of constituents that contribute to pharmacological effects for the genus Valeriana. Storage and extraction of valepotriates is a demanding task, as these compounds are thermolabile and unstable: even when decomposition products are not formed, isovaleric acid liberation from the iridoid nucleus originate compounds with less complex substituents. To study the influence of time and storage conditions on the diene valepotriates (valtrate, isovaltrate, acevaltrate, 1-β-acevaltrate, 1-β-aceacevaltrate) content of the Valeriana glechomifolia (native to southern Brazil), extract was obtained by supercritical fluid extraction using CO₂ as the fluid (SF-CO₂). Above-ground and below-ground material of V. glechomifolia was extracted by SF-CO₂ (40 °C, 90 bar). The extract was stored under nitrogen atmosphere or solubilised in methanol. Valepotriates stability was accessed during storage at -20 °C over 8 months through reverse-phase HPLC (mobile phase acetonitrile:water 50:50 (v/v); 254 nm). A gradual increase in valtrate levels and decrease in acevaltrate, 1-β-acevaltrate and 1-β-aceacevaltrate, concentration were observed from the first month of storage for the dry extract. However, for the methanol solubilised extract these changes occurred only after the third month and were accompanied by reduction in isovaltrate levels and formation of decomposition products. SF-CO₂ showed high selectivity for valepotriates extraction. This is the first report on valepotriates molecular conversion, which was less accelerated when the extract was stored in methanol, but under this condition degradation products are also present, probably baldrinals, that are not observed in the dry extract. Copyright © 2011 John Wiley & Sons, Ltd.

  12. Synthesis and characterization of PTP/[Fe(CN)3(dien)]·H2O nanocomposite; study of electrical, thermal and photocatalytic properties

    Moosvi, Syed Kazim; Majid, Kowsar; Ara, Tabassum


    Polythiophene/[Fe(CN)3(dien)]·H2O nanocomposite was synthesised by oxidative chemical polymerisation method. Photoadduct was synthesised by irradiating an equimolar mixture of potassium ferricyanide and diethylenetriamine which was then reduced to nanosize by high energy ball mill. The reduction of photoadduct to nanosize was confirmed from XRD. Nanocomposite of PTP with photoadduct was then prepared by oxidative chemical polymerisation using FeCl3 as oxidant. The successful synthesis of nanocomposite was confirmed from FTIR, XRD and SEM. TGA revealed higher thermal stability of nanocomposite as compared to pure PTP. I-V characteristics plotted on a log-log scale showed two distinct power law regions in case of nanocomposite. At lower voltages, the transport mechanism follows Ohm's law. At higher voltages, the mechanism is consistent with space charge-limited emission. Furthermore, nanocomposite shows enhanced conductivity as compared to pure PTP. From dielectric studies, an appreciable high value of dielectric constant (4.4 × 106 at 100 Hz) and ac conductivity (2.1 × 109 S/m at 300 kHz) of nanocomposite was obtained. This indicates the possible application of this nanocomposite in charge storage devices. The photocatalytic activity of the materials was studied against the methyl orange (MO) dye under UV-Vis light and 76% degradation of MO dye was achieved in presence of nanocomposite in just 2 h, hence indicating its better photocatalytic efficiency. Results thus obtained indicate the synthesised nanocomposite can be used as a multifunctional material for different nanoelectronic devices.

  13. Cubitene: an irregular twelve-membered-ring diterpene from a termite soldier. [1,5-dimethyl-8,10-bis(isopropenyl)cyclododeca-1,5-diene

    Prestwich, G.D. (International Centre of Insect Physiology and Ecology, Nairobi, Kenya); Wiemer, D.F.; Meinwald, J.; Clardy, J.


    Cubitene was isolated from the hexane extract of C. umbratus soldier heads by chromatography over Florisil followed by preparative GLC. High resolution mass spectroscopy indicated the formula of cubitene to be C/sub 20/H/sub 32/. Mass spectra of catalytically hydrogenated cubitene products showed peaks at m/rho 279, consistent with their formulation as substituted cycloalkanes of the composition C/sub 20/H/sub 40/. Cubitene is therefore a monocyclic hydrocarbon with four centers of unsaturation. the /sup 1/H NMR spectral data revealed the presence of two 1,1-disubstituted double bonds, and two additional olefinic protons. Four methyl groups attached to double bonds are also observed. The /sup 13/C NMR spectrum indicated the presence of two tribsubstituted double bonds. Fortunately, cubitene could be obtained in crystalline form (mp 34.5-35/sup 0/C) from cold methanol, allowing a single-crystal x-ray diffraction analysis. It crystallized in the monoclinic crystal class. Lattice parameters were: a = 15.963 (5), b = 6.799 (2), c = 17.038 (5) A; theta = 96.99 (2)/sup 0/. Evidence shows cubitene to be 1,5-dimethyl-8,10-bis(isopropenyl)cyclododeca-1,5-diene, a structure in which one isoprene unit is irregularly joined to three others. It appears to be the first example of a diterpene hydrocarbon based on a twelve-membered carbocyclic ring. Its biosynthesis poses interesting problems. Two possible biosynthetic routes are suggested. An even more basic question remains....whether termite soldiers synthesize cubitene at all, or whether they simply sequester it (or a closely related precursor) from their food.

  14. (2R*,4R*,7S*,10R*,12R*-3,11,13,15-Tetraoxapentacyclo[,7.02,4.010,12]pentadeca-5,8-dien-14-one

    Goverdhan Mehta


    Full Text Available The title compound, C11H8O5, features a `skipped' diene, an anti-bis(epoxide and a cyclic carbonate, all embedded in a densely functionalized [4.4.3]propellane scaffold. The crystal packing of this diepoxide is effected primarily by C—H...O hydrogen bonds, which link the molecules into tapes along the b axis. Inter-tape connectivity is brought about by centrosymmetrically disposed pairs of C...O contacts [3.183 (4 Å] between the Cδ+=Oδ- dipoles of neighbouring carbonate moieties.

  15. Magnetic field effect on the exciplex between all-s-trans- 1,4-diphenylbuta- 1,3-diene and 1,4-dicyanobenzene: a comparative study with other alpha,omega-diphenyl polyenes.

    Sengupta, T; Basu, S


    The exciplex between all-s-trans-1,4-diphenylbuta-1,3-diene and 1,4-dicyanobenzene has been studied by steady state fluorescence along with the magnetic field effect (MFE) and compared with the other alpha,omega-diphenyl polyenes. The exciplex formation and magnetic field effect are dictated by the chain length of the polyene rather than the electronic requirement of these phenomena. The wavelength dependence of the MFE confirms the presence of two different charge-transfer complexes.

  16. 3,4-Dihydroxy-1,6-bis(4-methoxyphenyl)hexa-2,4-diene-1,6-dione, its 4-methylphenyl analogue, and a potassium salt of 2-hydroxy-4-(4-methoxyphenyl)-4-oxobut-2-enoic acid.

    Nye, Luke; Turnbull, Mark M; Wikaira, Jan L


    Reaction of 4-methoxyacetophenone with diethyl oxalate under basic conditions produced 3,4-dihydroxy-1,6-bis(4-methoxyphenyl)hexa-2,4-diene-1,6-dione, C20H18O6, (1). The molecules lie across a crystallographic inversion centre and intramolecular hydrogen bonding, similar to acetylacetone, is observed, confirming that the molecule is in the di-enol-dione tautomeric form. Additional O-H...O hydrogen bonds link the molecules into chains parallel to the b axis. The structure is compared with that of redetermined 4-methylphenyl compound 3,4-dihydroxy-1,6-bis(4-methylphenyl)hexa-2,4-diene-1,6-dione, C20H18O4, (2), which crystallizes in a similar fashion. The salt, catena-poly[[μ2-2-hydroxy-4-(4-methoxyphenyl)-4-oxobut-2-enoato-κ(3)O(1),O(2):O(4)][μ2-2-hydroxy-4-(4-methoxyphenyl)-4-oxobut-2-enoic acid-κ(2)O(1):O(4)]potassium], [K(C11H9O5)(C11H10O5)]n, (3), was isolated as a by-product of the synthesis of (1). The two organic species are linked by a strong hydrogen bond between the carboxylic acid and carboxylate groups. They are further stabilized and linked into a double-chain structure via the seven-coordinate potassium ion.

  17. Ruthenium-catalyzed metathesis reactions of ortho- and meta-dialkenyl-carboranes: efficient ring-closing and acyclic diene polymerization reactions.

    Guron, Marta; Wei, Xiaolan; Carroll, Patrick J; Sneddon, Larry G


    The ruthenium-catalyzed metathesis reactions of dialkenyl-substituted ortho- and meta-carboranes provide excellent routes to both cyclic-substituted o-carboranes and new types of main-chain m-carborane polymers. The adjacent positions of the two olefins in the 1,2-(alkenyl)(2)-o-carboranes strongly favor the formation of ring-closed (RCM) products with the reactions of 1,2-(CH(2)=CHCH(2))(2)-1,2-C(2)B(10)H(10) (1), 1,2-(CH(2)=CH(CH(2))(3)CH(2))(2)-1,2-C(2)B(10)H(10) (2), 1,2-(CH(2)=CHSiMe(2))(2)-1,2-C(2)B(10)H(10) (3), 1,2-(CH(2)=CHCH(2)SiMe(2))(2)-1,2-C(2)B(10)H(10) (4), and 1,2-[CH(2)=CH(CH(2))(4)SiMe(2)](2)-1,2-C(2)B(10)H(10) (5) affording 1,2-(-CH(2)CH=CHCH(2)-)-C(2)B(10)H(10) (10), 1,2-[-CH(2)(CH(2))(3)CH=CH(CH(2))(3)CH(2)-]-1,2-C(2)B(10)H(10) (11), 1,2-[-SiMe(2)CH=CHSiMe(2)-]-1,2-C(2)B(10)H(10) (12), 1,2-[-SiMe(2)CH(2)CH=CHCH(2)SMe(2)-]-C(2)B(10)H(10) (13), and 1,2-[-SiMe(2)(CH(2))(4)CH=CH(CH(2))(4)SiMe(2)-]-C(2)B(10)H(10) (14), respectively, in 72-97% yields. On the other hand, the reaction of 1,2-(CH(2)-CHCH(2)OC(=O))(2)-1,2-C(2)B(10)H(10) (6) gave cyclo-[1,2-(1',8'-C(=O)OCH(2)CH=CHCH(2)OC(=O))-1,2-C(2)B(10)H(10)](2) (15a) and polymer 15b resulting from intermolecular metathesis reactions. The nonadjacent positions of the alkenyl groups in the 1,7-(alkenyl)(2)-m-carboranes, 1,7-(CH(2)=CHCH(2))(2)-1,7-C(2)B(10)H(10) (7), 1,7-(CH(2)=CH(CH(2))(3)CH(2))(2)-1,7-C(2)B(10)H(10) (8), and 1,7-(CH(2)=CHCH(2)SiMe(2))(2)-1,7-C(2)B(10)H(10) (9), disfavor the formation of RCM products, and in these cases, acyclic diene metathesis polymerizations (ADMET) produced new types of main chain m-carborane polymers. The structures of 3, 9, 11, 12, 13, and 15a were crystallographically confirmed.

  18. Advances in Reactor Technology for Selective Hydrogenation of Diene-Based Polymer%共轭双烯聚合物选择性加氢反应器技术进展

    蒋国强; 范娜; 丁富新


    The selective hydrogenation of conjugated diene-based polymer, including rubber and elastomer, can significantly improve the stability of the polymer. The hydrogenation reactor and the reaction process is one of the key technologies which impact the hydrogenation degree and efficiency. This review is focused on the progress in reactor technologies for selective hydrogenation of the conjugated diene-based polymer. Both the continuous stirred tank reactor (CSTR) including mechanical stirring reactor, the bubbling reactor and loop reactor, and the plug flow reactor ( PFR) including packed tower and static mixed tubular reactor, are employed to hydrogenate diene-based polymer. The technologies based on the combination of CSTR and PFR have been developed to improve the hydrogenation degree and process efficiency. According to the fluid dynamics and reaction kinetics of the hydrogenation system, the key issues impacting the hydrogenation degree and efficiency are analyzed and the potential way to promote hydrogenation and to reduce the energy/material consumption is summarized.%对以橡胶、弹性体为代表的含共轭双烯聚合物进行烯属双键的选择性加氢,可显著提高聚合物的稳定性;加氢反应器和反应工艺是制约加氢度和产率的关键技术之一.该文综述了目前共轭双烯聚合物选择性加氢反应器的技术进展,包括以机械搅拌反应器、鼓泡反应器、外循环反应器为代表的全混流型反应器;以填料塔和静态混合管式反应器为代表的平推流型反应器;以及各种反应器的组合技术、特殊操作方式.结合加氢体系的流体力学特征和反应动力学特征,分析了制约加氢度和产率的关键问题,总结了进一步提高加氢度和产率、降低能耗物耗的潜在途径.

  19. NBS karavīru motivācija dienēt Hercberga duālo faktoru motivācijas teorijas skatījumā

    Andrijausks, Arvīds


    Šī darba galvenais uzdevums ir apskatīt Latvijas NBS karavīru motīvus dienēt un interpretēt to caur Frederika Hecberga „duālo faktoru” teoriju. Karavīru motivācija un motivāciju galvenie ietekmējošie faktori tiek noskaidroti ar daļēji strukturēto interviju un ranga tabulas (kuras vienības ir ņemtas no 2007.gada „NBS karavīru dienesta motivācijas analīze un komplektēšanas ar personālu stratēģijas izstrāde” armijas projekta) palīdzību. Darbā tiek apskatīts motivācijas jēdziens, tā skaidrojums, ...

  20. C-24 stereochemistry of marine Sterols: (22E)-24-Ethyl-24-methylcholesta-5,22-dien-3{beta}-ol and 24-Ethyl-24-methylcholest-5-en-3{beta}-ol

    Echigo, Shizue; Uekusa, Hidehiro; Hara, Noriyuki; Fujimoto, Yoshinori [Tokyo Institute of Technology, Meguro, Tokyo (Japan). Dept. of Chemistry and Materials Science; Castellanos, Leonardo; Duque, Carmenza, E-mail: [Universidad Nacional de Colombia, Bogota (Colombia). Dept. de Quimica


    The C-24 configurations of (22E)-24-ethyl-24-methylcholesta-5,22-dien-3{beta}-ol (1) and 24-ethyl- 24-methylcholest-5-en-3{beta}-ol (2), isolated from the Colombian Caribbean sponge Topsentia ophiraphidites, were determined to be R and S, respectively, by comparing their NMR data with those of stereodefined (24R)- and (24S)-samples that were synthesized in routes involving the orthoester Claisen rearrangement of {Delta}{sup 23}-22-allylic alcohols. This is the first synthetic study where the Claisen rearrangement is used to introduce a C-24 quaternary center in a stereospecific manner with acceptable yield. X-ray analysis of 1 confirmed these stereochemical assignments. (author)

  1. ([2.2.2]Cryptand-κ6 O)potassium (η4-cyclo­octa­diene)bis­(η2-pyrene)cobaltate(1−) pentane hemisolvate

    Brennessel, William W.; Ellis, John E.


    The cation, anion, and solvent in the title compound, [K(C18H36N2O6)][Co(C8H12)(C16H10)2]·0.5C5H12, are well separated. The pentane solvent mol­ecules are found in channels along [100] and were modeled as disordered over crystallographic inversion centers. Using the mid-points of the coordinated olefins, the angle between the Cpy/Cpy–Co–Cpy/Cpy and the Ccod/Ccod–Co–Ccod/Ccod planes (py is pyrene and cod is cyclo­octa­diene) is 67.6 (2)°. Thus, the overall geometry of the coordination sphere around cobalt is best described as distorted tetra­hedral. PMID:22807709

  2. Lewis Acid and Substituent Effects on the Molecular Mechanism for the Nazarov Reaction of Penta-1,4-dien-3-one and Derivatives. A Topological Analysis Based on the Combined Use of Electron Localization Function and Catastrophe Theory.

    Polo, Victor; Andrés, Juan


    The joint use of the topological analysis provided by the electron localization function (ELF) and catastrophe theory (CT), at the B3LYP/6-31G(d) calculation level, allows us to examine the Lewis acid (protonation H(+) and presence of BH3) and the role of an electron donor substituent (-OCH3) at α and β positions along the course of the molecular mechanism for the Nazarov rearrangement of penta-1,4-dien-3-one and eight derivatives. The progress of the reaction is monitored by the changes of the ELF structural stability domains (SSDs), each change being controlled by a turning point derived from CT. These SSDs and the corresponding turning points are associated with a sequence of elementary chemical steps. Along the cyclization path of penta-1,4-diene-3-one, four SSDs as well as three turning points (cusp1-fold1-cusp2) have been characterized. The first and second SSDs correspond to a polarization of the C-O bond and electronic redistribution among the C-C bonds, respectively, and they can be associated with the formation of an oxyallyl structure. The third and fourth SSDs can be assigned to the ring closure process. Protonation of the oxygen atom shifts the reactive directly into the second SSD, greatly reducing the activation and reaction energies. The electronic effects due to Lewis acids and electron donor substituents have been rationalized in terms of calculations of mesomeric structures from ELF basin populations. The combination of Lewis acids together with α and β -OCH3 substitutions renders a cooperative and competitive effect on activation and reaction free energies, respectively.

  3. The glucocorticoid properties of the synthetic steroid pregna-1,4-diene-11beta-ol-3,20-dione (deltaHOP) are not entirely correlated with the steroid binding to the glucocorticoid receptor.

    Vicent, G P; Pecci, A; Ghini, A A; Piwien-Pilipuk, G; Veleiro, A S; Burton, G; Lantos, C P; Galigniana, M D


    The natural steroid 11beta-hydroxyprogesterone is not only a modulator of 11beta-hydroxy-steroid dehydrogenase activity, but also an efficient inducer of tyrosine aminotransferase activity in hepatocytes. In contrast with the low affinity for the mineralocorticoid receptor. 11beta-hydroxyprogesterone binds well to both the glucocorticoid receptor and the carrier protein transcortin. It is accepted that the introduction of a 1:ene double bond into 3-keto 4:ene steroids increases the glucocorticoid potency, so that 3-keto-1,4:diene steroids show improved chemical stability and are more potent glucocorticoids than their respective 4:ene analogs. The steroid pregna-1,4-diene-11beta-ol-3,20-dione (deltaHOP) had previously been described as an anti-inflamatory compound and an inhibitor of macromolecular biosynthesis in thymocytes and lymphocytes. In such studies, deltaHOP also exhibited some particular glucocorticoid properties which made it attractive as a tool for the study of the mechanism of action of glucocorticoids. In the present paper we show that deltaHOP possesses some classical biological actions of glucocorticoids such as deposition of glycogen in rat liver, induction of TAT activity in hepatocytes, and inhibition of the uptake of leucine and thymidine by thymocytes. It also exhibits minimal sodium-retaining properties. Consistent with these biological effects, deltaHOP shows a 70 times lower relative binding affinity for the mineralocortioid receptor than aldosterone, but a reasonable affinity for the glucocorticoid receptor, and is as efficient as dexamethasone in dissociating the 90 kDa heat shock protein from the glucocorticoid receptor heterocomplex. However, the inhibition of the uptake of amino acids and nucleotides observed in the presence of deltaHOP is not efficiently blocked when thymocytes are coincubated in the presence of steroids with known antiglucocorticoid activity. deltaHOP is similarly inefficient in inducing chloramphenicol

  4. Spectral, structural elucidation and coordination abilities of Co(II) and Mn(II) coordination entities of 2,6,11,15-tetraoxa-9,17-diaza-1,7,10,16-(1,2)-tetrabenzenacyclooctadecaphan-8,17-diene.

    Rajiv, Kumar; Rajni, Johar


    Designing tactics were tailored and followed by synthetic and formulation methodologies to prepare 2,6,11,15-tetraoxa-9,17-diaza-1,7,10,16-(1,2)-tetrabenzenacyclooctadecaphan-8,17-diene. Spectral techniques (MS, infrared, 1H NMR, 13C NMR, electronic and EPR), physiochemical measurements (elemental analysis, molar conductance and magnetic susceptibility), electrochemistry (cyclic voltammetry) and classical mechanics (molecular modeling) were employed for structural elucidation of Co(II) and Mn(II) coordination entities having N2O4 chromophore. Comparative spectral analysis revealed legating nature of N2O4 donor macrocycle and confirmed host/guest connectivity between ligand and metal(s). Mass spectrometry (MS) determined 1:1 stoichiometry in CEs. Further electrochemical study confirmed change in oxidation and reduction patterns of CEs. Inhibiting potential (antifungal screened against Aspergillus flavus) showed enhanced antimicrobial properties of CEs as compared to ligand. Molecular modeling was employed to find out different molecular features along with their stabilization energies.

  5. A comparison between the effects of gamma radiation and sulfur cure system on the microstructure and crosslink network of (styrene butadiene rubber/ethylene propylene diene monomer) blends in presence of nanoclay

    Shoushtari Zadeh Naseri, Aida; Jalali-Arani, Azam


    Rubber blends based on (styrene-butadiene rubber (SBR)/ethylene-propylene-diene monomer (EPDM)) with and without organoclay (OC) were prepared through a melt mixing process. The concentration ratio of the rubber phases (EPDM/SBR; 50/50 wt%) and the amount of the OC were kept constant. The samples were then vulcanized by means of gamma radiation using a Co-60 gamma source as well as sulfur cure system. The effect of absorbed dose on the formation of the crosslinks was confirmed by the Fourier transform infrared spectroscopy (FTIR). The effects of absorbed dose, sulfur cure system and OC on the gel content, and crosslink density were evaluated by the chemical tests. Applying the Charlesby-Pinner equation to estimate the radiation chemical yield, revealed that the use of OC in the blend caused 20% reduction in the degradation/crosslinking ratio. Employing the swelling test data, some thermodynamic parameters were determined. Using field emission scanning electron microscopy (FE-SEM) to investigate microstructure of the samples revealed a more homogeneous structure and also an increase in compatibility of the blend components in the sample cured by the irradiation in comparison to that cured by the sulfur curing system.

  6. Crystal structure of 7-phenyl-7-(2,4,5-trimethyl-3,6-dioxocyclohexa-1,4-dien-1-ylheptanoate 1,3-dihydroxy-2-(hydroxymethylpropan-2-aminium monohydrate: a new solid form of seratrodast

    Benyong Lou


    Full Text Available In the title hydrated salt, C4H12NO3+·C22H25O4−·H2O, seratrodast [systematic name: 7-phenyl-7-(2,4,5-trimethyl-3,6-dioxocyclohexa-1,4-dien-1-ylheptanoic acid] crystallized with trometamol [systematic name: 2-amino-2-(hydroxyméthylpropane-1,3-diol] to form a monohydrated salt form of seratrodast. The carboxylic acid group of seratrodast has transferred its proton to the amino N atom of trometamol. In the crystal, the trometamol cations are linked to the water molecules and to each other by N—H...O and O—H...O hydrogen bonds forming sheets parallel to (100. The seratrodast anions are linked to both sides of these sheets by O—H...O and C—H...O hydrogen bonds, forming a three-layer two-dimensional structure. After forming the title salt, the solubility of seratrodast was found to be greatly improved.

  7. Chemical reactivity of Ro-26-9228, 1alpha-fluoro-25-hydroxy-16,23E-diene-26,27-bishomo-20-epi-cholecalciferol in aqueous solution.

    Brandl, Michael; Wu, Xiaoyang; Liu, Yanzhou; Pease, Joseph; Holper, Marites; Hooijmaaijer, Elvira; Lu, Yvonne; Wu, Ping


    The degradation of Ro-26-9228, 1alpha-fluoro-25-hydroxy-16,23E-diene-26,27-bishomo-20-epi-cholecalciferol, 2, was studied in aqueous solution in the pH range of 1.17-10.56 and in alcohol solutions, at 25, 40, and 50 degrees C. The degradation of Ro-26-9228 was found to be acid catalyzed and to be independent of potassium acetate buffer concentration. Above pH 4, the reaction rate is independent of pH, with a T90 of 14.3 h at 25 degrees C in pH 7.75 buffer. 19F nuclear magnetic resonance was used to study the ratio of the vitamin (6-s-trans) to previtamin form in acetonitrile at 40 degrees C. The equilibrium percentage of previtamin and the rate of approach to equilibrium were 13.8% and 0.2 h(-1), respectively. Nuclear magnetic resonance was used to elucidate the structure of the degradation products. Novel products were formed from the elimination of the fluorine and addition of solvent to C9, with formation occurring through the previtamin form. Additional degradation products result from reaction of the side chain 25-hydroxyl and addition of solvent to C1.

  8. 16-hydroxy-cleroda-3,13-dien-16,15-olide induced glioma cell autophagy via ROS generation and activation of p38 MAPK and ERK-1/2.

    Thiyagarajan, Varadharajan; Sivalingam, Kalai Selvi; Viswanadha, Vijaya Padma; Weng, Ching-Feng


    16-hydroxy-cleroda-3,13-dien-16,15-olide (HCD), a natural product isolated from medicinal plant Polyalthia longifolia exhibits anticancer activity through caspase-independent apoptosis in brain tumors, as previously reported. This study further attempted to investigate the involvement of HCD-induced autophagy in brain tumor cell lines neuroblastoma N18 and glioma C6 through the induction of reactive oxygen species (ROS) and the activation of p38 and ERK-1/2 pathway. The results demonstrated that HCD increased the hyper-generation of ROS and decreased cellular antioxidant enzymes, such as superoxide dismutase (SOD), glutathione (GSH), glutathione peroxidase (GPx), and glutathione s transferase (GST). Furthermore, HCD increased the expressions of autophagic marker proteins LC3-II and Beclin-1 in a time- and dose-dependent manner. Additionally, HCD was found to significantly induce p-p38 MAPK and p-ERK-1/2 proteins by Western blot, which implies that HCD is a potential therapeutic anticancer agent that exerts its activity through inducing ROS-mediation for the autophagy of brain tumor cells.

  9. Therapeutic effects of C-28 methyl ester of 2-cyano-3,12-dioxoolean-1,9-dien-28-oic acid (CDDO-Me; bardoxolone methyl) on radiation-induced lung inflammation and fibrosis in mice.

    Wang, Yan-Yang; Zhang, Cui-Ying; Ma, Ya-Qiong; He, Zhi-Xu; Zhe, Hong; Zhou, Shu-Feng


    The C-28 methyl ester of 2-cyano-3,12-dioxoolean-1,9-dien-28-oic acid (CDDO-Me), one of the synthetic triterpenoids, has been found to have potent anti-inflammatory and anticancer properties in vitro and in vivo. However, its usefulness in mitigating radiation-induced lung injury (RILI), including radiation-induced lung inflammation and fibrosis, has not been tested. The aim of this study was to explore the therapeutic effect of CDDO-Me on RILI in mice and the underlying mechanisms. Herein, we found that administration of CDDO-Me improved the histopathological score, reduced the number of inflammatory cells and concentrations of total protein in bronchoalveolar lavage fluid, suppressed secretion and expression of proinflammatory cytokines, including transforming growth factor-β and interleukin-6, elevated expression of the anti-inflammatory cytokine interleukin-10, and downregulated the mRNA level of profibrotic genes, including for fibronectin, α-smooth muscle actin, and collagen I. CDDO-Me attenuated radiation-induced lung inflammation. CDDO-Me also decreased the Masson's trichrome stain score, hydroxyproline content, and mRNA level of profibrotic genes, and blocked radiation-induced collagen accumulation and fibrosis. Collectively, these findings suggest that CDDO-Me ameliorates radiation-induced lung inflammation and fibrosis, and this synthetic triterpenoid is a promising novel therapeutic agent for RILI. Further mechanistic, efficacy, and safety studies are warranted to elucidate the role of CDDO-Me in the management of RILI.

  10. A focal adhesion kinase inhibitor 16-hydroxy-cleroda-3,13-dien-16,15-olide incorporated into enteric-coated nanoparticles for controlled anti-glioma drug delivery.

    Thiyagarajan, Varadharajan; Lin, Shi-Xiang; Lee, Chia-Hung; Weng, Ching-Feng


    16-Hydroxy-cleroda-3,13-dien-16,15-olide (HCD) which is extracted from a medicinal plant, Polyalthia longifolia, was shown to exhibit anticancer activity through apoptosis and FAK inhibition in our previous study. To improve its solubility and efficacy, a novel HCD delivery system using copper-substituted mesoporous silica nanoparticles (MSNs) was designed as a delivery vehicle, and the outer surfaces of MSNs were further coated with enteric polymers to prevent the drug from leaching in the stomach acid. All the data regarding synthesis and physical characterization, including Zeta potential, FT-IR spectra, N2 adsorption-desorption isotherms (BET), drug loading, powder X-ray diffraction, Thermo gravimetric analysis (TGA), Transmission electron microscopy (TEM), and Scanning electron microscopy (SEM) were well characterized. The non-coated MSN-HCD exposed to acidic pH (1.2) showed a rapid degradation of the drug, whereas the enteric-coated samples presented a sustained release profile in the gastrointestinal pHs. Cell cytotoxicity was further confirmed by the MTT-C6 Glioma cell line, in vitro. When compared with the control and pure HCD, the MSN-HCD revealed a potential anti-proliferation effect via the synergistic effect of the drug and the MSN vehicle. Additionally, this MSN-HCD had the effect of increasing the reactive oxygen species (ROS) levels and altered the Mitochondria membrane potential (MMP) in C6 cell line. The in vivo anti-tumor efficacy of enteric-coated MSN-HCD was evaluated by C6 Glioma bearing xenograft nude mice, and enteric-coated MSN-HCD clearly exhibited the greatest anti-glioma activity, as compared to the pure HCD and the untreated control. In terms of the effective treatment of brain glioma, this study provides conclusive evidence of the successful development of the anti-cancer agent HCD conjugated with enteric-coated MSN as a delivery control mechanism with enhanced dissolution characteristics.

  11. Ent-pimara-8(14), 15-dien-19-oic acid isolated from the roots of Aralia cordata inhibits induction of inflammatory mediators by blocking NF-kappaB activation and mitogen-activated protein kinase pathways.

    Kang, Ok-Hwa; Chae, Hee-Sung; Choi, Jang-Gi; Oh, Yoo-Chang; Lee, Young-Seob; Kim, Jong-Hak; Seung, Man-Jun; Jang, Hye-Jin; Bae, Ki-Hwan; Lee, John-Hwa; Shin, Dong-Won; Kwon, Dong Yeul


    Macrophages play central roles in the innate immune system. The roots of Aralia cordata are widely used in Oriental medicine as a remedy for arthritis. During our program to screen medicinal plants for potential anti-inflammatory compounds, ent-pimara-8(14), 15-dien-19-oic acid (pimaradienoic acid; PA) was isolated from the roots of A. cordata. We examined the effect of PA on pro-inflammatory mediators in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. PA was found to significantly inhibit the production of nitric oxide (NO), prostaglandin E(2) (PGE(2)), and interleukin-6 (IL-6), as well as the expressions of inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2), and IL-6. Furthermore, we examined whether mitogen-activated protein kinases (MAPKs) and phosphatidylinositol 3-kinase (PI3K) signaling pathways are involved in LPS-induced RAW 264.7 cells. We found that a p38 inhibitor (SB203580) and an ERK 1/2 inhibitor (PD98059) significantly affected LPS-induced IL-6 production. In contrast, a JNK 1/2 inhibitor (SP600125) and PI3K inhibitor (wortmannin or LY294002) did not block the induction of IL-6 production by LPS. The LPS-induced phosphorylation of p38 MAPK and extracellular signal-regulated kinase 1/2 (ERK1/2) was inhibited by PA, but not the phosphorylation of JNK 1/2 and AKT (Ser473). Moreover, PA suppressed I kappaB alpha degradation, NF-kappaB activation and luciferase activity. These results suggest that PA isolated from A. cordata has a potential regulatory effect on inflammatory iNOS, COX-2 and IL-6 expression through blockade of the phosphorylation of MAPKs following I kappaB alpha degradation and NF-kappaB activation.

  12. Manyeto-Reolojik Etilen Propilen Dien Monomer ve Doğal Kauçuk Türü Sentetik Kauçukların İzotrop ve Anizotrop Durumda Mekanik Özelliklerinin İncelenmesi

    Uğur Mazlum


    Full Text Available Manyeto-reolojik (MR malzemeler dış manyetik alan uygulamalarıyla tersinir ve hızlı bir şekilde kontrol edilebilen reolojik özelliklere sahip akıllı(smart malzeme sınıfındandır. Gelişen teknoloji koşulları göz önüne alındığında kauçuk türü akıllı malzemeler manyeto-reolojik etkilerle beraber daha fonksiyonel bir kullanıma sahip olmuştur. Bu çalışmada, manyeto-reolojik Etilen Propilen Dien Monomer (EPDM ve Doğal Kauçuk (NR türü sentetik kauçukların izotrop ve anizotrop durumda tek eksenli yükleme altındaki mekanik özelliklerinin incelenmesi amaçlanmıştır. Bu tür kompozit malzemeler geleneksel sıcak kalıp sistemi yardımıyla izotrop (homojen ve anizotrop (hizalanmış olarak ferromanyetik toz ilave edilerek ve manyetik alan uygulanarak elde edilmiştir. Elde edilen kompozit malzemelere manyetik alanın etkisi incelenmiştir. Çalışmada EPDM sentetik kauçuk malzemesinin aksine NR kauçuğunun akıllı malzeme özelliğine daha yatkın olduğu gözlemlenmiştir.

  13. Studies on the rheological,phase morphologic,thermal and mechanical properties of poly(trimethylene terephthalate)/ethylene propylene diene monomer copolymer grafted with maleic anhydride/metallocene polyethylene blends

    RUN Mingtao; SONG Hongzan; WANG Yingjin; YAO Chenguang; GAO Jungang


    s The rheological,phase morphologic,thermal and mechanical properties of poly(trimethylene terephthalate)/metallocene polyethylene(PTT/mPE)blends in the presence of ethylene propylene diene monomer copolymer grafted with maleic anhydride(EPDM-g-MAHl as compatibilizer are studied by means of a capillary rheometer,scanning electron microscopy(SEM),differential scanning calorimetry (DSC)and thermogravimetric analyzer (TGA).Results suggest that the compatibility of PTT/mPE blends is improved greatly after the addition of a compatibilizer.The radius of the dispersed phase in the system decreases greatly when the compatibilizer is added into the blend.When the amount of compatibilizer exceeds 8 wt-%,the size of dispersed phase becomes larger again.This phenomena could be attributed to the higher viscosity of the EPDM-g-MAH phase,which is dispersed more difficulty in the PTT phase of lower viscosity,thus the mixing efficiency is apparently decreased during the melt blending process.Moreover,the melt viscosity of the blend reaches the maximal value in case of 4 wt-%compatibilizer content,above which it would decrease again.This result is associated with the generation of more and bigger dispersed phase inside the bulk phase,thus the grafting efficiency at the interface is decreased,which could result in lower viscosity.The DSC results suggest that the mPE component shows a nucleating effect,and could increase the overall degree and rate of PTT crystallization,while the addition of a compatibilizer might slightly diminish these effects.In addition,the blend with 4 wt-% compatibilizer shows the best thermal stability.Furthermore,the Izod impact strength and the tensile strength at room temperature of the blend are also markedly improved by the addition of a 4-8 wt-% compatibilizer.

  14. Cytoprotection of human endothelial cells against oxidative stress by 1-[2-cyano-3,12-dioxooleana-1,9(11)-dien-28-oyl]imidazole (CDDO-Im): application of systems biology to understand the mechanism of action.

    Wang, Xinyu; Bynum, James A; Stavchansky, Solomon; Bowman, Phillip D


    Cellular damage from oxidative stress, in particular following ischemic injury, occurs during heart attack, stroke, or traumatic injury, and is potentially reducible with appropriate drug treatment. We previously reported that caffeic acid phenethyl ester (CAPE), a plant-derived polyphenolic compound, protected human umbilical vein endothelial cells (HUVEC) from menadione-induced oxidative stress and that this cytoprotective effect was correlated with the capacity to induce heme oxygenase-1 (HMOX1) and its protein product, a phase II cytoprotective enzyme. To further improve this cytoprotective effect, we studied a synthetic triterpenoid, 1-[2-cyano-3,12-dioxooleana-1,9(11)-dien-28-oyl]imidazole (CDDO-Im), which is known as a potent phase II enzyme inducer with antitumor and anti-inflammatory activities, and compared it to CAPE. CDDO-Im at 200nM provided more protection to HUVEC against oxidative stress than 20μM CAPE. We explored the mechanism of CDDO-Im cytoprotection with gene expression profiling and pathway analysis and compared to that of CAPE. In addition to potent up-regulation of HMOX1, heat shock proteins (HSP) were also found to be highly induced by CDDO-Im in HUVEC. Pathway analysis results showed that transcription factor Nrf2-mediated oxidative stress response was among the top canonical pathways commonly activated by both CDDO-Im and CAPE. Compared to CAPE, CDDO-Im up-regulated more HSP and some of them to a much higher extent. In addition, CDDO-Im treatment affected Nrf2 pathway more significantly. These findings may provide an explanation why CDDO-Im is a more potent cytoprotectant than CAPE against oxidative stress in HUVEC.

  15. Synthesis and Application of 1-(Pyridin-2-yl)-2-azabuta-1,3-dienes%1-(2-吡啶基)-2-氮杂-1,3-丁二烯的合成与应用

    杨维芳; 徐晓丽; 张站斌


    1-(Pyridin-2-yl)-2-azabuta-1,3-dienes (2) prepared from pyridine-2-carboxaldehyde underwent Diels-Alder reac-tion with electron-poor dienophiles such as alkenes and alkynes to give 6-(pyridin-2-yl)piperidin-2-ones and dihydro-6-(pyri-din-2-yl)pyridin-2-ones. Dihydro-6-(pyridin-2-yl)pyridin-2-one was oxidized with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) to afford 6-(pyridin-2-yl) pyridin-2-one. Treatment of 6-(pyridin-2-yl)pyridin-2-one with phosphorus oxychloride gave bipyridine derivative.%以2-吡啶甲醛为起始原料制备1-(2-吡啶基)-2-氮杂-1,3-丁二烯(2),然后与烯烃、炔烃发生Diels-Alder反应分别得到6-(2-吡啶基)-2-哌啶酮和6-(2-吡啶基)-二氢-2-吡啶酮。用2,3-二氯-5,6-二氰基-1,4-苯醌(DDQ)氧化6-(2-吡啶基)-二氢-2-吡啶酮得到6-(2-吡啶基)-2-吡啶酮,最后用三氯氧磷处理得到联吡啶类化合物。

  16. Diurnal variations of progesterone, testosterone, and androsta-1,4-diene-3,17-dione in the rumen and in vitro progesterone transformation by mixed rumen microorganisms of lactating dairy cows.

    Ren, Qing-Chang; Yang, Hong-Jian; Li, Sheng-Li; Wang, Jia-Qi


    Five Holstein lactating dairy cows fed 5 total mixed rations (TMR) with different forage combinations were used in a 5 × 5 Latin square design to investigate diurnal variations of progesterone (P4), testosterone, and androsta-1,4-diene-3,17-dione (ADD) concentrations in the rumen. Meanwhile, different P4 inclusion levels [0 (control), 2, 20, 40, 80, and 100 ng/mL in culture fluids] were incubated in vitro for 6, 12, 24, 36, 48, and 72 h together with rumen mixed microorganisms grown on a maize-rich feed mixture (maize meal:Chinese ryegrass hay = :1) with an aim to determine microbial P4 transformation into testosterone and ADD. Ruminal P4, testosterone, and ADD concentrations of lactating dairy cows were greater in the TMR with forage combination of corn silage plus alfalfa hay or Chinese wild ryegrass hay than the TMR with the corn stover-based forage combination. The diurnal fluctuation pattern showed that P4, testosterone, and ADD concentrations in the rumen were greater at nighttime than daytime and peaked 6h after feeding in the morning or afternoon. The in vitro batch cultures showed that the P4 elimination rate was highest at the P4 addition of 20 ng/mL and declined with the further increased addition of P4. The treatments after dosing P4 exhibited a shorter time than the control group until half of the initial P4 inclusion was eliminated (i.e., half time), and the lowest half time (1.46 h) occurred at the P4 addition of 20 ng/mL. In summary, the ruminal steroids concentration was affected by forage type and quality, and the rumen microorganisms exhibited great ability to transform P4 into testosterone and ADD, depending on incubation time and initial P4 addition level, suggesting that the host might affect the metabolism of its rumen microorganisms via the endogenous steroids. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  17. Anticarcinogenic effect of bis-1,7-(2-hydroxyphenyl)-hepta-1,6-diene-3,5-dione a curcumin analog on DMH-induced colon cancer model.

    Devasena, T; Rajasekaran, K N; Gunasekaran, G; Viswanathan, P; Menon, Venugopal P


    1,2-Dimethylhydrazine (DMH) is a toxic environmental pollutant which was reported also to be a colon-specific carcinogen. This study was performed to study the effect of bis-1,7-(2-hydroxyphenyl)-hepta-1,6-diene-3,5-dione, a bisdemethoxycurcumin analog (BDMC-A) on DMH-induced colon carcinogenesis in male Wistar rats and effects were compared with that of the reference drug, curcumin. Rats were given a weekly subcutaneous injection of DMH (20mg/kg body weight) in the groin, for 15 weeks. After a total experimental period of 32 weeks (including 2 weeks of acclimatization) tumor incidence was 100% in DMH-treated rats. Tumor was identified histologically as adenocarcinoma. Dysplasia, papillary pattern, cellular pleomorphism and carcinomatous glands were also noticed in DMH-treated rats. However, there was no colonic tumor in DMH+BDMC-A- and DMH+curcumin-treated rats but, lymphocyte infiltrations were observed. The levels of total bile acids and cholesterol in 24h fecal samples were significantly lower in DMH administered rats when compared to control rats, while, the excretion of bile acids and cholesterol were significantly increased and was near normal levels in DMH+BDMC-A- and DMH+curcumin-treated rats. In DMH-induced tumor bearing rats the levels of colonic and intestinal cholesterol was significantly increased whereas, the levels of phospholipid was decreased with a concomitant increase in the activities of phospholipase A (PLA) and phospholipase C (PLC), compared to untreated control rats. Intragastric administration of BDMC-A and curcumin to DMH administered rats significantly lowered the cholesterol content and raised the phospholipid content and lowered the activities of PLA and PLC towards near normal values. Our study shows that the protective effect of BDMC-A during DMH-induced colon carcinogenesis may be due to its modulatory effects on (i). histological changes, (ii). bile acids, (iii). cholesterol, and (iv). phospholipid metabolism in the target organ

  18. Comparison of Current Chemical and Stereochemical Tests for the Identification and Differentiation of Pelargonium graveolens L'Hér. (Geraniaceae Essential Oils: Analytical Data for (--(1S, 4R, 5S-Guaia-6,9-diene and (--(7R,10S-10-epi-γ-Eudesmol

    Mei Wang


    Full Text Available Commercial geranium oil samples, steam-distilled oils of authenticated plant samples, and a reference sample were investigated by GC/MS to determine the validity and applicability of a series of chemical and stereochemical tests that have been proposed in the literature to identify the country of origin, phytochemical identity or authenticity of geranium oils. The chemical tests evaluated include the ratio of the concentrations of geraniol to citronellol and the presence or absence of certain sesquiterpenes, viz., (-- guaia-6,9-diene and (--10-epi-γ-eudesmol. The stereochemical tests include the stereochemical distribution of i citronellol, ii menthone and isomenthone, and iii rose oxides. The most reliable chemical test was the presence or absence of the sesquiterpene probes. The stereochemical tests proved to be less reliable. Most of the tests could be used to classify geranium oils into general types; however, none of the tests provided a foolproof method to distinguish cultivars or country of origin. During this study, the ambiguity in the absolute stereochemistry of (--10-epi-γ-eudesmol and (--guaia-6,9-diene was addressed, and these two sesquiterpenes could serve as effective markers for the authentication of P. graveolens essential oils.

  19. MMHD [(S,E)-2-methyl-1-(2-methylthiazol-4-yl) hexa-1,5-dien-ol], a novel synthetic compound derived from epothilone, suppresses nuclear factor-kappaB-mediated cytokine expression in lipopolysaccharide-stimulated BV-2 microglia.

    Jeon, Na-Ra; Koppula, Sushruta; Kim, Byung-Wook; Park, Su-Ho; Lee, Hyo-Won; Choi, Dong-Kug


    The effects of MMHD [(S,E)-2-methyl-1-(2-methylthiazol-4-yl) hexa-1,5-dien-ol], a novel synthetic compound derived from epothilone, was investigated for its effects on the expression of proinflammatory mediators in lipopolysaccharide-stimulated BV-2 microglia. MMHD attenuated the expressions of inducible nitric oxide synthase and cyclooxygenase-2 mRNA and protein without affecting cell viability. Moreover, MMHD suppressed nuclear factor-kappaB (NF-kappaB) activation via the translocation of p65 into the nucleus. These results indicate that MMHD exerts anti-inflammatory properties by suppressing the transcription of proinflammatory cytokine genes through the NF-kappaB signaling pathway.

  20. Caraterização composicional do AES - um copolímero de enxertia de poli(estireno-co-acrilonitrila em poli(etileno-co-propileno-co-dieno Compositional characterization of AES a graft copolymer based on poly(styrene-co-acrylonitrile and poly(etyhlene-co-propylene-co-diene

    Renato Turchet


    Full Text Available O objetivo deste trabalho é a caracterização do AES, um copolímero de enxertia de poli(estireno-co-acrilonitrila, SAN, em poli(etileno-co-propileno-co-dieno, EPDM. Para tanto, o AES foi submetido à extração seletiva de seus componentes: o SAN livre, o EDPM livre, e o copolímero de enxertia EPDM-g-SAN. O AES e suas frações foram caracterizados por espectroscopia de infravermelho, análise elementar, calorimetria diferencial de varredura e ressonância magnética nuclear, RMN¹H e RMN13C. O AES analisado apresenta a seguinte composição em massa: 65% de EPDM-g-SAN, 13% de EPDM livre e 22% de SAN livre. O EPDM apresenta 69,8% em massa de etileno, 26,5% em massa de propileno e 4,6% em massa do dieno, 2-etilideno-5-norboneno, ENB. O SAN apresenta razão em massa acrilonitrila/estireno de 28/72 e distribuição randômica de comonômeros de estireno e acrilonitrila. Estes resultados são concordantes com a composição do AES fornecida pelo fabricante, indicando que a metodologia proposta é adequada.This work aims the characterization of AES, a graft copolymer based on poly(styrene-co-acrylonitrile, SAN, and poly(etyhlene-co-propylene-co-diene, EPDM. AES was submitted to selective extraction of its components: free SAN, EPDM chains and the graft copolymer EPDM-g-SAN. AES and its fractions were characterized by infrared spectroscopy, elemental analysis, differential scanning calorimetry, 13C and ¹H nuclear magnetic resonance. The AES has 65 wt % of EPDM-g-SAN, 13 wt % of free EPDM and 22 wt % of free SAN. EPDM has 69.8 wt % of ethylene, 26.5 wt % of propylene and 4.6 wt % of diene, 2-ethylidene-5-norbonene ENB. SAN presents acrylonitrile/styrene mass ratio of 28/72 and a random distribution of acrylonitrile and styrene comonomers. These results are in agreement with the composition reported by the AES supplier, indicating that the proposed methodology is adequate.


    Khalil Faghihi; Akram Feyzi


    Six dicarboxylic acids 3a-3f were synthesized by the reaction of 3,3',4,4'-benzophenonetetracarboxylic dianhydride 1 with L-aminoacids 2a-2f in a solution of glacial acetic acid/pyridine (Py) at refluxing temperature.Then six new poly(amide-imide)s PAIs were synthesized from the direct polycondensation reaction of [N,N'-(4,4'-carbonyldiphtaloyl)-bis-L-amino diacid]s with 1,5-bis(4-aminophenyl)penta-1,4-dien-3-one (APPD).The polymerization reactions produced a series of new optically active PAIs with high yield and good inherent viscosity.Also these PAIs are optically active and soluble in various organic solvents.These resulting new polymers can be used in column chromatography for the separation of enantiomeric mixtures.The resulted polymers were fully characterized by means of FTIR and 1H-NMR spectroscopy,elemental analyses,inherent viscosity measurements,solubility tests and thermogravimetric analysis (TGA).

  2. Deletion of the gene encoding the reductase component of 3-ketosteroid 9α-hydroxylase in Rhodococcus equi USA-18 disrupts sterol catabolism, leading to the accumulation of 3-oxo-23,24-bisnorchola-1,4-dien-22-oic acid and 1,4-androstadiene-3,17-dione.

    Yeh, Chin-Hsing; Kuo, Yung-Shun; Chang, Che-Ming; Liu, Wen-Hsiung; Sheu, Meei-Ling; Meng, Menghsiao


    The gene encoding the putative reductase component (KshB) of 3-ketosteroid 9α-hydroxylase was cloned from Rhodococcus equi USA-18, a cholesterol oxidase-producing strain formerly named Arthrobacter simplex USA-18, by PCR according to consensus amino acid motifs of several bacterial KshB subunits. Deletion of the gene in R. equi USA-18 by a PCR-targeted gene disruption method resulted in a mutant strain that could accumulate up to 0.58 mg/ml 1,4-androstadiene-3,17-dione (ADD) in the culture medium when 0.2% cholesterol was used as the carbon source, indicating the involvement of the deleted enzyme in 9α-hydroxylation of steroids. In addition, this mutant also accumulated 3-oxo-23,24-bisnorchola-1,4-dien-22-oic acid (Δ1,4-BNC). Because both ADD and Δ1,4-BNC are important intermediates for the synthesis of steroid drugs, this mutant derived from R. equi USA-18 may deserve further investigation for its application potential.

  3. 奠边府走滑断裂带的构造特征、遥感解译及其区域构造意义%Structural Characteristics of the Dien Bien Phu Strike Slip Fault Zone and Its Regional Tectonic Implication

    唐渊; 刘俊来; TRAN My Dung; 宋志杰


    位于越南西北部的奠边府(Dien Bien Phu)断裂,向北延伸入中国云南境内,向南进入老挝境内,走向由近N-S向向南逐渐过渡为NE-SW向,倾角陡立.沿断裂带发育3个具有不同运动学机制的第四纪盆地--婵讷(Chan Nua)盆地、莱州(Lai Chau)盆地和奠边府盆地.根据对奠边府断裂带地区ETM遥感数据进行详细解译以及野外实地考察,得到奠边府断裂具有早期的右行走滑和后期的左行走滑特征的证据;并且根据断裂两侧水系受断裂影响发生左错的程度不同,认为奠边府断裂的西盘相对于东盘较为活动,即为主动盘.奠边府断裂北延进入越南境内,与金平地区的三家河断裂相连,并继续向北并入哀牢山剪切带中.奠边府断裂现今的左行走滑与红河断裂现今的右行走滑共同组成了一组共轭断裂系.

  4. 蒙脱土对膨胀阻燃三元乙丙橡胶/乙酸乙烯酯橡胶共混胶性能的影响%Effects of montmorillonite on properties of intumescent flame retardant ethylene-propylene-diene monomer/ethylene-vinyl acetate rubber blends

    董明哲; 谷晓昱; 吴卫东; 张胜; 黄庆; 孙军; 赵斌


    采用熔融共混法制备了蒙脱土(MMT)与膨胀阻燃剂(IFR)阻燃的三元乙丙橡胶/乙酸乙烯酯橡胶( EPDM/EVM)共混胶,用X射线衍射仪对其结构进行了表征,考察了MMT对共混胶力学性能、阻燃性能与热稳定性的影响.结果表明,在含有MMT的膨胀阻燃EPDM/EVM共混胶中,形成了插层型/剥离型的共存体系;MMT可显著提高膨胀阻燃共混胶体系的力学性能、热稳定性和成炭性,但对极限氧指数贡献不大.%The intumescent flame retardant ethylene-propylene-diene monomer(EPDM)/ethylene-vinyl acetate rubber (EVM) blends were prepared with montmorillonite ( MMT) and intumeseent flame retardant (IFR) through melt blending process. The structure of the blends was characterized by X-ray diffractometer, and the mechanical properties, flame re-tardancy, thermal stability of the blends were investigated. The results showed that the intercalated/exfoliated structure was formed in intumescent flame retardant EPDM/EVM blends contained MMT. MMT could improve the mechanical properties, thermal stability and char forming characteristics of intumescent flame retardant EPDM/EVM blends evidently, however, MMT showed little effect on limiting oxygen index.

  5. 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.

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


    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.

  6. Synthesis and Crystal Structure of (3Z, 5Z)-4,5-Diphenyl-3,6-Bis (Tosyl)Octa-3,5-Diene%(3Z,5Z) -4,5-二苯基-3,6-二(对甲苯磺酰基)-3,5-辛二烯的合成及其晶体结构

    束官莹; 林高峰; 刘长青; 谢美华


    通过CuI催化的二乙基锌与炔基砜的alpha -加成-偶联反应合成了标题化合物(3Z,5Z)-4,5-二苯基-3,6-二(对甲苯磺酰基)-3,5-辛二烯.化合物经1H NMR,13C NMR,IR,HR MS表征,化合物的结构经X-射线单晶衍射分析确证.晶体属三斜晶系,空间群P-1,晶胞参数:a=10.1113(12),b=10.1656(12),c=16.0942(19)(A),α=83.3590(10),β=72.5550(10),γ=73.0650( 10)°,V=1509.0(3)(A)3,Z=2,Dc=1.256g/cm3,μ=0.213 mm-1,F(000) =604,结构偏离因子R1=0.0564,wR2=0.1671,共收集到10810个独立衍射点,其中I>2σ(I)的可观测点为4260个.%The title compound (3Z,5Z)-4, 5-diphenyl-3,6-bis(tosyl)octa-3,5-diene was synthesized by Cul-catalyzed tandem alpha-addition-hornocoupling reaction of acetylenic sulfone and diethylzinc. The title compound was characterized by ' H NMR, 13C NMR, IR, HRMS and single-crystal X-ray diffraction analysis. The crystal belongs to triciinic system, space group P- 1 with a= 10.1113(12), b= 10.1656(12), c= 16.0942(19)A, a = 83.3590(10),β=72.5550(10),y=73.0650(10)°, V= 1509.0(3)A3, Z = 2, Dc= 1.256 g/cm3,μ=0.213 mm-1, F(000)=604, the final R,=0.0564 and wR2=0.1671, a total of 10810 reflections were collected, of which 4260 observed reflections with I>2σ(I) were observed.

  7. 改性3-十五碳烯基苯基缩水甘油醚对三元乙丙橡胶/炭黑/白炭黑复合材料性能的影响%Effects of modified glycidyl 3-pentadecenyl phenyl ether on properties of ethylene propylene diene monomer/carbon black/silica composite

    王舒婷; 岑兰; 龚湛林; 陈福林; 周彦豪


    A cross-linked polymer(M-GPPE) was synthesized by maleic anhydride and glycidyl 3-pen-tadecenyl phenyl ether ( GPPE) , and the structure of the obtained product was characterized.The effects of M-GPPE amount on cure characteristics , mechan-ical and dynamic mechanical properties , and filler dispersity of ethylene propylene diene monomer ( EPDM)/carbon black/silica composite were studied.The results showed that the presence of some active groups , such as anhydride group , in the molecular chain of M-GPPE resulted in higher ther-mal stability of M-GPPE than GPPE.GPPE played the role of a plasticizer in EPDM composite , thus extending curing time.The addition of 6 phr M-GPPE led to lower minimum torque , shorter scorch time and curing time as well as higher damp-ing value of the composite.The tensile strength and tear strength of the composite with 6 phr M-GPPE were increased by 35% and 8%, respectively.Transmission electron microscope analysis indicated that the dispersion of the filler in matrix was im-proved by M-GPPE, which reduced agglomeration of silica.%合成并表征了马来酸酐/3-十五碳烯基苯基缩水甘油醚(GPPE)的交联物(M-GPPE),研究了其对三元乙丙橡胶/炭黑/白炭黑复合材料硫化特性、力学性能、动态力学性能和填料分散性的影响。结果表明,M-GPPE分子链上存在酸酐等活性基团,热稳定性比GPPE高;GPEE在复合材料中主要起增塑剂作用,并且可延缓硫化时间;在复合材料中加入6份(质量) M-GPPE可使其最小转矩下降,焦烧时间和正硫化时间缩短,拉伸强度和撕裂强度分别提高35%和8%,在40~70℃具有较高的损耗值;透射电镜的分析表明M-GPPE可改善填料在基质中的分散性,减少了白炭黑的团聚。

  8. Franciscus van Assisi: Sy teologie van barmhartige diens

    R.B. (Botha van Aarde


    Full Text Available One of the most remarkable men in church history was Giovanni Bernardone (1182-1226, nicknamed Franciscus of Assisi. After his conversion he took Jesus� instruction to his disciples in Mark 6:8 to hart and made poverty his �bride�. The historical background of church and society in the 13th century had a major impact on his theology. He objected against the negative effects of the crusades, economy of prosperity and growing humanism of the time. His bondage to God, mankind and nature later became the major characteristic of the mendicant order of the Franciscans. St. Franciscus� theology of compassionate ministry was also a reaction to the scholasticism with its focus on reason. Scholasticism �believed in order to understand�. It was a theology (philosophy of the intellectuals at the universities in Europe and focussed mainly on the mind/reason. In St. Franciscus� theology the mistic (as a reaction against the scholasticism and the mediaeval piety flowed into one. This mistical piety focussed on the emotions of man and touched lay people.

  9. 24-Methyllanosta-7,25-dien-3-one

    Masood Parvez


    Full Text Available The title compound [systematic name: 17-(5,6-dimethylhept-6-en-2-yl-4,4,10,13,14-pentamethyl-1,5,6,10,11,12,13,15,16,17-decahydro-2H-cyclopenta[α]phenanthren-3(4H,9H,14H-one], C31H50O, is a triterpenoid which was isolated from Skimmia laureola. The three six-membered rings adopt chair, slightly distorted half-chair and distorted boat conformations, and the five-membered ring is in an envelope conformation. All the rings are trans fused. In the crystal structure, there is a weak C—H...O hydrogen bond.

  10. Tandem isomerization/telomerization of long chain dienes

    Laura eTorrente Murciano


    Full Text Available The first example of a tandem reaction involving double-bond migration in combination with telomerization is reported. Homogeneous and heterogeneous Ru catalysts were employed as isomerisation catalysts, and telomerization was realized using a homogeneous Pd(0 precursor complex with a N-heterocyclic carbene (IMes ligand. Overall conversions approaching 60 % were achieved with the best selectivity to telomerization products of 91% attained at 11 % conversion. Conversion was markedly higher in the presence of longer-chain alcohol (1-butanol as the nucleophile (telogen.

  11. 1,4-Disilacyclohexa-2,5-diene

    Tibbelin, Julius; Wallner, Andreas; Emanuelsson, Rikard


    (UPS), and cyclic voltammetry. A particularly strong neutral cyclic cross-hyperconjugation was observed in 1c. Its lowest electron binding energy (7.1 eV) is distinctly different from that of 1b (8.5 eV). Molecular orbital analysis reveals a stronger interaction between filled π(C[double bond, length...... as m-dash]C) and π(SiR2) group orbitals in 1c than in 1a and 1b. The energy shift in the highest occupied molecular orbital is also reflected in the first oxidation potentials as observed in the cyclic voltammograms of the respective compounds (1.47, 0.88, and 0.46 V for 1a, 1b and 1c, respectively...

  12. Leiers wat dien en b�dien. �n Pauliniese beskrywing van kerkleiers en hulle funksies in 1 & 2 Korinti�rs

    J Vermeulen


    Full Text Available What constitutes the functions and the essence of Pauline church leadership? How functional, relevant and useful is the huge amount of secular and religious� literature� published annually regarding leadership, for the church of Jesus Christ? In an effort to answer these and other questions, this essay studies portions of First and Second Corinthians, and comes to two conclusions. Firstly,� that� Pauline church leaders were characterised by service and� servanthood, and� secondly, that they also functioned as the mediators of pneumatological realities. Both of these dimentions function wholly within the paradigm of humility and dependance upon God, who is shown by Paul to be the source, as well as the focus of the superlative glory that characterises the ministry of the new covenant. The effects of the Pauline ministry functions simultaneously as the fruits, as well as the criteria of Pauline ministry in the new covenant.

  13. Anti-inflammatory profile of dehydrocostic acid, a novel sesquiterpene acid with a pharmacophoric conjugated diene.

    Hernández, V; Máñez, S; Recio, M C; Giner, R M; Ríos, J L


    Sesquiterpene acids are natural products that, in contrast with the thoroughly studied sesquiterpene lactones, have received little pharmacological attention. A good source of this class of compounds is Inula viscosa (Asteraceae), a plant with documented anti-inflammatory effects. The present paper gives the results of our investigations on the biochemical mechanisms involved in the anti-inflammatory activity of one such compound, dehydrocostic acid. The most salient findings were that in vitro dehydrocostic acid inhibits leukotriene B(4) production (IC(50)=22 microM), elastase activity (IC(50)=43 microM) and bee venom phospholipase A(2) activity (IC(50)=17 microM). Furthermore, this sesquiterpenoid was effective on some models of acute edema induced by PLA(2) and 12-O-tetradecanoylphorbol 13-acetate (TPA) Comparison of these data with that known for ilicic acid firmly suggests that the presence of a semiplanar ring A is essential for an improved inhibitory activity on inflammatory mediators.

  14. Crystal structure of 1,6-dithiacyclodeca-cis-3,cis-8-diene (DTCDD

    Russell G. Baughman


    Full Text Available The title compound, C8H12S2 (trivial name DTCDD, was obtained as a side product of the reaction between cis-1,4-dichlorobut-2-ene and sodium sulfide. The asymmetric unit consists of one-quarter of the molecule (S site symmetry 2 and the complete molecule has 2/m (C2h point symmetry with the C=C bond in an E conformation. The geometry of the title compound is compared to those of a chloro derivative and a mercury complex.

  15. Reformasie as herstel van die ware diens van God: enkele aanwysers by Calvyn en Zwingli

    L.F. Schulze


    Full Text Available Reformation as restoration of the true service of God - some indicators in the work of Calvin and ZwingliIn this article an attempt is made to interpret the 16th century Reformation from a rarely mentioned, yet very real perspective, viz., as a restoration of the true service of God. It is indicated that the true service o f God is an overarching concept, encompassing more than simply an ecclesiastical reform, or a return to the Bible. Besides these aspects, true service o f God implies the renewal o f life with all its social, economical and political overtones, which cannot be discussed in full in an article. Data drawn from some works o f Calvin and Zwingli will hopefully prove the validity o f this perspective and offer Christians in the "new South Africa" thought-provoking ideas which should be put into action.

  16. 1-CHLORO-(2S, 3S)-DIHYDROXYCYCLO-HEXA-4, 6-DIENE. (R826113)

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  17. Chlorido(η4-cycloocta-1,5-diene(N,N′-diethylthiourea-κSrhodium(I

    Giovanna Brancatelli


    Full Text Available In the title rhodium(I complex, [RhCl(C8H12(C5H12N2S], N,N′-diethylthiourea acts as a monodenate S-donor ligand. The rhodium(I coordination sphere is completed by the Cl atom and the COD [= 1,5-cyclooctadiene] ligand interacting through the π-electrons of the double bonds. If the midpoints of these two bonds are taken into account, the Rh atom exhibits a distorted square-planar coordination. The syn conformation of the N,N′-diethylthiourea ligand with respect to the Cl atom is stabilized by an intramolecular N—H...Cl hydrogen bond. A weak intermolecular N—H...Cl interaction links molecules along the a axis.

  18. Intermolecular hydroaminoalkylation of alkenes and dienes using a titanium mono(formamidinate) catalyst.

    Dörfler, Jaika; Preuss, Till; Brahms, Christian; Scheuer, Dennis; Doye, Sven


    An easily accessible formamidinate ligand-bearing titanium complex initially synthesized by Eisen et al. is used as catalyst for intermolecular hydroaminoalkylation reactions of unactivated, sterically demanding 1,1- and 1,2-disubstituted alkenes and styrenes with secondary amines. The corresponding reactions, which have never been achieved with titanium catalysts before, take place with excellent regioselectivity (up to 99 : 1) and in addition, corresponding reactions of 1,3-butadienes with N-methylbenzylamine are also described for the first time.

  19. Polar, Functional Diene-Based Materials: Free Radical Polymerization of 2-Cyanomethyl-1,3-Butadiene

    Jing, Y [Iowa State Univ., Ames, IA (United States)


    This thesis presented here focuses on the synthesis of 2-cyanomethyl-l ,3-butadiene and the free-radical polymerization of this monomer. In addition to the bulk, solution and emulsion polymerizations,, copolymerization with styrene and acrylonitrile will also be discussed. The comonomers were chosen due to the potential applications mentioned above. Furthermore, the thermal properties and rnicrostructures of the homopolymers and the copolymers are examined.

  20. Between ethylene and polyenes--the non-adiabatic dynamics of cis-dienes

    Kuhlman, Thomas Scheby; Glover, William J; Mori, Toshifumi;


    excitation to S1. It is observed that torsion around the carbon-carbon double bonds is essential in reaching a conical intersection seam connecting S1 and S0. We identify two timescales; the induction time from excitation to the onset of population transfer back to S0 (CPD: -25 fs, Me4-CPD: -71 fs...

  1. ' n Prakties-teologiese begronding vir Gemeentebou as kommunikatiewe handeling in diens van die evangelie

    J. C. an der Merwe


    Full Text Available A practical theological foundation for church growth as communicative act in the service of the gospel. The aim of this article is to reflect on a pracical theological perspective on the theoretical premises of church growth. This is done within the framework of the postmodern paradigm. Church growth focuses on the analysis, description and explanation of the practical situations of congregations in order to enhance church management. The episttmological framework of this aricleis the distinction metatheory, basis theory and theory of practice. The focus is on the relationship between basis theory and the theory of the practice of church growth. The aricle departs from an approach where empirical data form the basis for the construction of a praxis for church growth. The author argues for a biblical foundation by means of which the empirical data should be evaluated in order to devise a model for praxis.

  2. (2E,4E-1-(2-Hydroxyphenyl-5-phenylpenta-2,4-dien-1-one

    W. A. Silva


    Full Text Available In the structure of the title chalcone, C17H14O2, derived from cinnamaldehyde, the olefine group has a trans configuration. The molecular conformation is stabilized by an intramolecular O—H...O hydrogen-bond interaction with graph-set motif S(6.

  3. Incasso : de rechtsverhouding van de opdrachtgever met de incassant en diens beroepsaansprakelijkheid

    Vogel, Johannes Nicolaas Gerardus


    Debt collecting is a rather unknown phenomenon. Even insiders are not always aware of the (exact) juridical consequences. For instance, which obligations arise from the legal relationship between the client and the debt collector and what does the professional liability imply. The author has tried t

  4. Intramolecular Formal anti-Carbopalladation/Heck Reaction: Facile Domino Access to Carbo- and Heterooligocyclic Dienes.

    Pawliczek, Martin; Milde, Bastian; Jones, Peter G; Werz, Daniel B


    An intramolecular domino process consisting of a formal anti-carbopalladation followed by Heck reaction is realized. Complex oligo(hetero)cyclic scaffolds are efficiently obtained in one synthetic step from easily obtainable enyne precursors. In contrast to common syn-carbopalladation reactions of alkyne units, the carbopalladation employed here is designed to afford an anti-arrangement of the two new substituents across the emerging double bond. A prerequisite is that the residues next to the alkyne should lack any β-hydrogen atoms. The method paves the way to tri- and tetrasubstituted double-bond systems that have not been accessible by conventional Pd catalysis. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Valuation of the rice sector in the Quang Dien district, Vietnam : A case study of the rice sector in three communes in the Quang Dien district Thua Thien Hué Province, Vietnam

    Duijvendijk, K.


    The Tam Giang - Cau Hai lagoon is the largest of its kind in South East Asia and covers an area of 22,000 ha. The lagoon is located in the area with the highest rainfall in Vietnam; there are two main seasons, a dry and a wet season. Seasonal problems to the productivity of rice can thus change from

  6. Isolation of stigmast-5,24-dien-3-ol from marine brown algae Sargassum tenerrimum and its antipredatory activity

    Majik, M.S.; Adel, H.; Shirodkar, D.; Tilvi, S.; Furtado, J.

    - diabetic,13 antihistaminic, and anticholinergic.14 Additionally, Vahouny et al. reported that fucosterol reduces the gastrointestinal absorption of cholesterol15 and Hagiwara et al. observed that, fucosterol decreases angiotensin converting enzyme levels...

  7. Pentacyclo[,6.14,8.19,13]octadeca-1(2,8(9-diene

    Savvas Ioannou


    Full Text Available The title compound, C18H24, was the main product of thermolysis of noradamantene dimer (heptacyclo[,6.14,8.19,13.01,9.02,8]octadecane. The crystal structure was determined to prove that the thermolysis product of noradamantene dimer is favored by stretch release due to ring opening of the four-membered ring. The bond length of the quaternary C atoms of the starting material was calculated as 1.6 Å, enlarged in comparison to other single bonds. After the rearrangement, the stretch release of the above carbons leads to an increase of the distance between them (2.824 Å with respect to the crystallographic data.

  8. (22E,24R-3β,5α,9α-Trihydroxyergosta-7,22-dien-6-one monohydrate

    Zhi-Hong Xu


    Full Text Available The title ergosterol compound, C28H44O4·H2O, is composed of four fused rings (three six-membered and one five-membered and a side chain. It is a derivative of ergosterol and was isolated from a marine-derived halotolerant fungus, Cladosporium cladosporioides PXP-49. In the crystal, molecules are assembled by classical O—H...O hydrogen bonds, forming a two-dimensional network, with base vectors [100] and [010]. The absolute configuration was assigned from the measured optical rotation and reference to the literature. An intramolecular O—H...O hydrogen bond occurs.

  9. Limitations of using Raman microscopy for the analysis of high-content-carbon-filled ethylene propylene diene monomer rubber

    Ghanbari-Siahkali, A.; Almdal, K.; Kingshott, P.


    on the sample, ranging from 4.55 mW to 0.09 mW. The surface of the EPDM was analyzed before and after laser exposure using X-ray photoelectron spectroscopy (XPS) and attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy. The techniques have surface probe depths of approximately less......) analysis was also performed on the Raman analyzed areas to visually illustrate the effects created due to laser light exposure (i.e., burning marks). The change in surface chemistry also occurs in regions a few millimeters from the exposed sites, indicating that the effect is quite long range. However...

  10. 2-(2-Azabicyclo[3.2.1]octa-3,6-dien-2-yl-1,3-dimethoxyimidazolium hexafluoridophosphate

    Simone Haslinger


    Full Text Available The title salt, C12H16N3O2+·PF6−, was obtained by the dipolar cycloaddition of norbornadiene to 2-azido-1,3-dimethoxyimidazolium hexafluoridophosphate. The methoxy groups attached to the imidazolium ring of the cation adopt an anti conformation [displacements of the C atoms from the ring plane = 1.386 (4 and −1.404 (3 Å]. In the crystal, weak inter-ionic C—H...F contacts are observed. The structure was refined as a two-component twin. Positional disorder of the fluorine atoms of the PF6 anion was observed, the occupancy ratio being 0.562 (16:0.438 (16.

  11. Crystal structure of (Z-3-benzyloxy-6-[(2-hydroxy-5-methylanilinomethylidene]cyclohexa-2,4-dien-1-one

    Nadir Ghichi


    Full Text Available In the title Schiff base compound, C21H19NO3, the conformation about the C=C bond is Z. The N—H group and carbonyl O atom form an intramolecular N—H...O hydrogen bond with an S(6 ring motif. The benzyloxy ring and the 2-hydroxy-5-methylphenyl ring are inclined to the central six-membered ring by 13.68 (9 and 9.13 (8°, respectively, and to one another by 21.95 (9°. In the crystal, molecules are linked by O—H...O hydrogen bonds, forming helical chains along [010].

  12. 中国与奠边府战役%China and the Battle of Dien Bien Phu




  13. Activité biologique d'un agoniste non stéroïdien de l'hormone de ...

    newly ecdysed 3rd and 4th instar larvae under laboratory conditions. The insecticide ... Key words: insect growth regulators; halofenozide; toxicology; biochemistry; mosquitos; Culiseta longiareolata. ..... des mues létales précoces chez Culex.

  14. Crystal structure of (η2,η2-cycloocta-1,5-diene(η5-indenylcobalt(I

    Phillip Jungk


    Full Text Available The title compound, [Co(C8H12(C9H7], was synthesized by the reaction of metallated 2-H-indene with CoCl(PPh33 and 1,5-cyclooctadiene in tetrahydrofuran/toluene. In the molecule, the CoI atom is coordinated by the two double bonds of the 1,5-cyclooctadiene ligand and η5-bonded to the indenyl ligand. The asymmetric unit contains two molecules of the CoI complex with very similar conformations. In the crystal, molecules are arranged into rows parallel to [100]. Apart from dispersion forces, there are no notable intermolecular interactions in the crystal.

  15. Organometallic Catalysis in Diene and Cyclo-olefin Polymerisation Processes. II. The Metathesis Reaction in Polymer Chemistry

    Dolgoplosk, B. A.; Korshak, Yu V.


    The development of ideas concerning the mechanism of the metathesis reaction and its employment in polymer chemistry are examined. The possible applications of the metathesis reaction in the synthesis of polymers by the polymerisation of cycloolefins and cyclodienes with ring opening and via the degradation of high-molecular-weight rubbers and their modification are discussed. The bibliography includes 160 references.

  16. Diastereoselective Synthesis of 5-Hydroxy-8-methoxy-1-oxaspiro[5,5]undeca-7,10-diene-9-one

    Thomas W. Scully


    Full Text Available A short five steps synthesis of the title compound from vanillin is described. The racemic spiroether 7 was obtained in 61% yield and in >99% diastereomeric excess (by 1H-NMR from the corresponding phenolic derivative 3 by oxidation with lead (IV acetate.

  17. Stereoselective Synthesis of 8,12-Furanoeudesmanes from Santonin. Absolute Stereochemistry of Natural Furanoeudesma-1,3-diene and Tubipofurane.

    Blay, Gonzalo; Cardona, Luz; García, Begoña; Pedro, José R.; Sánchez, Juan J.


    Ketobutenolide 3, easily obtained from santonin (1), has been transformed into two natural furanoeudesmanes 4 and 5, isolated from Commiphora molmol and Tubipora musica, respectively. trans- And cis-decalin systems were obtained by stereoselective reduction of the C(4)-C(5) double bond in 3 in the following way: hydrogenation of 3 over Pd/C followed by acidic treatment gave the cis isomer 10 as the major product; selective hydrogenation of the C(1)-C(2) double bond with the Wilkinson's catalyst followed by reduction with NaTeH yielded mainly the trans isomer 9. Compounds 9 and 10 were transformed into 4 and 5 in parallel sequences. Optical rotation and CD measurements of the synthetic products revealed that the stereochemistry of both natural products should be revised to their enantiomeric form.

  18. Influence of various stabilizers on ageing of dicumyl peroxide-cured polypropylene/ethylene-propylene-diene thermoplastic vulcanizates

    Naskar, K.; Kokot, D.; Noordermeer, J.W.M.


    Stabilizers are used to prevent the degradation of polymers and thereby, to effectively extend their useful lifetime. However, the application of stabilizers in combination with a peroxide-cure system needs special care, because the main function of these materials is to deactivate the radicals form

  19. Highly Stereoselective Heterogeneous Diene Polymerization by Co-MFU-4l: A Single-Site Catalyst Prepared by Cation Exchange.

    Dubey, Romain J-C; Comito, Robert J; Wu, Zhenwei; Zhang, Guanghui; Rieth, Adam J; Hendon, Christopher H; Miller, Jeffrey T; Dincă, Mircea


    Molecular catalysts offer tremendous advantages for stereoselective polymerization because their activity and selectivity can be optimized and understood mechanistically using the familiar tools of organometallic chemistry. Yet, this exquisite control over selectivity comes at an operational price that is generally not justifiable for the large-scale manufacture of polyfolefins. In this report, we identify Co-MFU-4l, prepared by cation exchange in a metal-organic framework, as a solid catalyst for the polymerization of 1,3-butadiene with high stereoselectivity (>99% 1,4-cis). To our knowledge, this is the highest stereoselectivity achieved with a heterogeneous catalyst for this transformation. The polymer's low polydispersity (PDI ≈ 2) and the catalyst's ready recovery and low leaching indicate that our material is a structurally resilient single-site heterogeneous catalyst. Further characterization of Co-MFU-4l by X-ray absorption spectroscopy provided evidence for discrete, tris-pyrazolylborate-like coordination of Co(II). With this information, we identify a soluble cobalt complex that mimics the structure and reactivity of Co-MFU-4l, thus providing a well-defined platform for studying the catalytic mechanism in the solution phase. This work underscores the capacity for small molecule-like tunability and mechanistic tractability available to transition metal catalysis in metal-organic frameworks.

  20. Crystal structure of (Z-3-benzyloxy-6-[(2-hydroxyanilinomethylidene]cyclohexa-2,4-dien-1-one

    Nadir Ghichi


    Full Text Available In the title compound, C20H17NO3, the methylidenecyclohexa-2,4-dienone moiety is approximately planar [maximum deviation = 0.0615 (10 Å] and is oriented at diherdral angles of 69.60 (7 and 1.69 (9° to the phenyl and hydroxybenzene rings, respectively. The amino group links with the carbonyl O atom via an intramolecular N—H...O hydrogen bond, forming an S(6 ring motif. In the crystal, the molecules are linked by O—H...O hydrogen bonds and weak C—H...O and C—H...π interactions, forming a three-dimensional supramolecular architecture.

  1. Catalytic Enantioselective Carbon-Carbon Bond Formation by Addition of Dialkylzinc Reagents to Cyclic 1,3-Diene Monoepoxides.

    Badalassi, F.; Crotti, P.; Macchia, F.; Pineschi, M.; Arnold, L.A.; Feringa, B.L.


    Chiral copper complexes of 2,2'-binaphthyl-based phosphorus amidites are shown to be highly effective catalysts for the conjugate addition of dialkylzinc reagents to vinyloxiranes. The corresponding allylic alcohol reaction products (SN2'-pathway) were obtained with moderate to high regioselectivity

  2. Palladium-based telomerization of1,3-buta diene with glycerol using methoxy-functionalized triphenylphosphine ligands

    Palkovits, R.; Nieddu, I.; Kruithof, C.A.; Klein Gebbink, R.J.M.; Weckhuysen, B.M.


    Glycerol is considered a potential renewable building block for the synthesis of existing as well as new chemicals. A promising route is the telomerization of 1,3-butadiene with glycerol leading to C8 chain ethers of glycerol with applications in, for example, surfactant chemistry. Recently, we repo

  3. (3R,4S,5S,8S,10R,13R-3-Hydroxykaura-9(11,16-dien-18-oic acid

    Karren D. Beattie


    Full Text Available The title compound, C20H28O3, was isolated during our investigation into the chemical composition and pharmacological activity of Centipeda cunninghamii (DC. A. Braun & Asch. (Asteraceae. The enantiopure compound, a diterpene with a carbon skeleton, is composed of three six- and one five-membered rings in chair, twist-boat, half-chair and envelope conformations, respectively. Each molecule makes one intra- and one intermolecular O—H...O hydrogen bond in the crystal lattice, forming hydrogen-bonded chains along [010]. The absolute configuration of the compound was assigned on the basis of optical rotation measurements.

  4. Diversification of ortho-Fused Cycloocta-2,5-dien-1-one Cores and Eight- to Six-Ring Conversion by σ Bond C-C Cleavage.

    Eccleshare, Lee; Lozada-Rodríguez, Leticia; Cooper, Phillippa; Burroughs, Laurence; Ritchie, John; Lewis, William; Woodward, Simon


    Sequential treatment of 2-C6 H4 Br(CHO) with LiC≡CR(1) (R(1) =SiMe3 , tBu), nBuLi, CuBr⋅SMe2 and HC≡CCHClR(2) [R(2) =Ph, 4-CF3 Ph, 3-CNPh, 4-(MeO2 C)Ph] at -50 °C leads to formation of an intermediate carbanion (Z)-1,2-C6 H4 {CA (=O)C≡CB R(1) }{CH=CH(CH(-) )R(2) } (4). Low temperatures (-50 °C) favour attack at CB leading to kinetic formation of 6,8-bicycles containing non-classical C-carbanion enolates (5). Higher temperatures (-10 °C to ambient) and electron-deficient R(2) favour retro σ-bond C-C cleavage regenerating 4, which subsequently closes on CA providing 6,6-bicyclic alkoxides (6). Computational modelling (CBS-QB3) indicated that both pathways are viable and of similar energies. Reaction of 6 with H(+) gave 1,2-dihydronaphthalen-1-ols, or under dehydrating conditions, 2-aryl-1-alkynylnaphthlenes. Enolates 5 react in situ with: H2 O, D2 O, I2 , allylbromide, S2 Me2 , CO2 and lead to the expected C-E derivatives (E=H, D, I, allyl, SMe, CO2 H) in 49-64 % yield directly from intermediate 5. The parents (E=H; R(1) =SiMe3 , tBu; R(2) =Ph) are versatile starting materials for NaBH4 and Grignard C=O additions, desilylation (when R(1) =SiMe) and oxime formation. The latter allows formation of 6,9-bicyclics via Beckmann rearrangement. The 6,8-ring iodides are suitable Suzuki precursors for Pd-catalysed C-C coupling (81-87 %), whereas the carboxylic acids readily form amides under T3P® conditions (71-95 %).

  5. Heck reaction on protected 3-alkyl-1,2-dien-1-ols: an approach to substituted 3-alkenylindoles, 2-alkoxy-3-alkylidene-2,3-dihydrobenzofuranes and -indolidines.

    Boi, Tommaso; Deagostino, Annamaria; Prandi, Cristina; Tabasso, Silvia; Toppino, Antonio; Venturello, Paolo


    A phosphine-free annulation reaction has been exploited for the preparation of substituted 3-alkenylindoles, 2-alkoxy-3-alkylidene-2,3-dihydrobenzofuranes and -indolidines in good to excellent yields. This has been done by reaction of protected 3-alkyl-1,2-dienols with o-iodophenols or protected o-iodoanilines. Two different heterocyclic skeletons were obtained, depending on the electron-donating properties of the heteroatom involved in the annulation process.

  6. Development of new chiral auxiliary from the Diels-Alder adduct endo-tricyclo[,7] undeca-4 ,9-dien-3 ,6-dione

    Suély Copini


    Full Text Available Stereochemistry control is very important in organic synthesis and it is a basic challenge in asymmetric synthesis. An approach widely used is making use of chiral auxiliary compounds. In this work it is showed the synthesis of highly optically pure rigid polycyclic compounds from the Diels-Alder adduct 1. Compounds 1-3 were prepared as described by Ito et. al. [1]. The alcohol (--3 was obtained by biotransformation of diketone 2 with Mucor ramosissimus, e.e.>99% (60%. The polycyclic halides 4-6 were synthesized (60-97% after treatment of alcohol (--3 with NBS, NIS and, NCS in dichloromethane, respectively. Compound 7 was prepared by reaction with p-toluenesulfonic acid, whilst 8 was prepared by treatment of (--3 with m-chloroperbenzoic acid. The strained polycylic alcohols 9-13 will be achieved by reduction of ketones 4-8 with NaBH4. All compounds were identified by 1H and 13C NMR spectroscopy. Due to intrinsic rigidity of the synthesized polycyclic, they could be of use as chiral auxiliary agents. Prochiral substrates can be readily attached by many ways to C-3 or through hydroxyl group found in compounds 8-13. The stereo-dirigent potential of these polycyclic can also be increased by directly or indirectly introduction of many groups at position C-3, or at adjacent positions to carbonyl or hydroxyl at C-3 and C-10.

  7. Crystal structure of (1,3-di-tert-butyl-η5-cyclo­penta­dien­yl)tri­methyl­hafnium(IV)

    Pérez-Redondo, Adrián; Varela-Izquierdo, Víctor; Yélamos, Carlos


    The mol­ecule of the title organometallic hafnium(IV) com­pound, [Hf(CH3)3(C13H21)] or [HfMe3(η5-C5H3-1,3-tBu2)], adopts the classical three-legged piano-stool geometry for mono­cyclo­penta­dienylhafnium(IV) derivatives with the three methyl groups bonded to the Hf(IV) atom at the legs. The C atoms of the two tert-butyl group bonded to the cyclo­penta­dienyl (Cp) ring are 0.132 (5) and 0.154 (6) Å above the Cp least-squares plane. There are no significant inter­molecular inter­actions present between the mol­ecules in the crystal structure. PMID:25995884

  8. Crystal structure of (1,3-di-tert-butyl-η(5)-cyclo-penta-dien-yl)tri-methyl-hafnium(IV).

    Pérez-Redondo, Adrián; Varela-Izquierdo, Víctor; Yélamos, Carlos


    The mol-ecule of the title organometallic hafnium(IV) com-pound, [Hf(CH3)3(C13H21)] or [HfMe3(η(5)-C5H3-1,3- (t) Bu2)], adopts the classical three-legged piano-stool geometry for mono-cyclo-penta-dienylhafnium(IV) derivatives with the three methyl groups bonded to the Hf(IV) atom at the legs. The C atoms of the two tert-butyl group bonded to the cyclo-penta-dienyl (Cp) ring are 0.132 (5) and 0.154 (6) Å above the Cp least-squares plane. There are no significant inter-molecular inter-actions present between the mol-ecules in the crystal structure.

  9. Reëling van die Gereformeerde predikant se diens – ’n arbeidsregtelike of ’n interne kerklike aangeleentheid?

    J. Smit


    Full Text Available Regulation of a Reformed minister’s office – a labour law or internal church matter? In this article it is argued that Labour Law is not applicable on the relationship between a minister and a church council to the Reformed Churches in South Africa. The main focus of the argument is that Labour Law does not have the purpose to regulate a relationship based on an exegetic-dogmatically founded foundation. It is also argued that a minister in the Reformed Churches in South Africa cannot be considered an employee of the church council because of the calling he received from the Lord. The calling of a minister is the main indication that he is not an employee of the church council, but a servant of the Lord. Therefore it is also stated that the Church Order does not regulate the minister’s office on a contractual basis, but that the Church Order regulates the calling of a minister. Labour Law intents to regulate the labour aspect of a person’s life while the Church Order applies to a minister’s whole life.

  10. War to Resistance Against France by the Vietnamese and the Campaign of Dien Bien Phu%越南抗法战争与奠边府战役




  11. (η2,η2-Cycloocta-1,5-diene[2-(diphenylphosphanylmethylpyridine-κ2N,P]rhodium(I tetrafluoridoborate 1,2-dichloroethane monosolvate

    Siping Wei


    Full Text Available The title compound, [Rh(C8H12(C18H16NP]BF4 has been prepared as a precatalyst for applications in rhodium-catalysed additions of carbocyclic acids to terminal alkynes leading to anti-Markovnikov Z-enol esters. Here the triclinic pseudopolymorph of the title compound is presented. In contrast to the earlier reported pseudopolymorph (orthorhombic space group [Wei et al. (2013. Chem. Eur. J. 19, 12067–12076], the triclinic polymorph contains half a molecule of dichloromethane as solvent in the asymmetric unit. The rhodium(I atom exhibits a square-planar coordination. The estimated diffraction contribution of the disordered solvent (a half molecule of dichloroethane per asymmetric unit was subtracted from the observed diffraction data using the SQUEEZE [Spek (2015. Acta Cryst. C71, 9–16] routine in PLATON. The given chemical formula and other crystal data do not take the solvent into account.

  12. Thermolytic Behavior of 4-Fold Bridged syn-Tricyclo[,5)]octa-3,7-dienes.

    Brand, Stefan; Gleiter, Rolf


    The syntheses of the 4-fold-bridged compounds syn-1,2,3,4,5,6,7,8,9,10,11,12-dodecahydro-8b,12b-butanobenzo[3',4']cyclobuta[1',2':3,4]cyclobuta[1,2-e]biphenylene (7), syn-1,4,5,8,9,12-hexahydro-8b,12b-(but-3-eno)benzo[3',4']cyclobuta[1',2':3,4]cyclobuta[1,2-e]biphenylene (8), and 2,3,4,5,6,7,8,9,10,11,12,13,14,15-tetradecahydro-10b,15b-pentano-1H-cyclobuta[1",2":2,3;3",4":3',4']dicyclobuta[1,2:3,4:1',2']triscycloheptene (9) have been achieved starting from the cyclic diynes 10-12. Heating 7 and 8 at 200 degrees C without solvent leads to 1,2,3,4,5,6,7,8,9,10,11,12-dodecahydro-8b,12b-butanobenzo[3,4]cyclobuta[1,2-l]phenanthrene (18) and 1,4,5,8,9,12-hexahydro-8b,12b-(but-3-eno)benzo[3,4]cyclobuta[1,2-l]phenanthrene (19). Both systems contain a bridged bicyclo[4.2.0]octa-2,4,7-triene skeleton. The thermolysis of 9 yields (Delta(5a,5b;10a,11;11a,16a;17,17a))-2,3,4,5,6,7,8,9,10,12,13,14,15,16-tetradecahydro-11,17-pentano-1H-triscyclohepta[a,c,f]cyclooctene (20), a 4-fold-bridged cyclooctatetraene derivative. Treatment of 8 with DDQ leads to the dehydrogenation products 21 and 22. The different behavior in the thermolysis of 7 and 8 as compared to 9 is ascribed to the different lengths of the bridges.

  13. Diels-Alder Cycloadditions: A MORE Experiment in the Organic Laboratory Including a Diene Identification Exercise Involving NMR Spectroscopy and Molecular Modeling

    Shaw, Roosevelt; Severin, Ashika; Balfour, Miguel; Nettles, Columbus


    Two Diels-Alder reactions are described that are suitable for a MORE (microwave-induced organic reaction enhanced) experiment in the organic chemistry laboratory course. A second experiment in which the splitting patterns of the vinyl protons in the nuclear magnetic resonance (NMR) spectra of two MORE adducts are used in conjunction with molecular…

  14. (18-Crown-6potassium [(1,2,5,6-η-cycloocta-1,5-diene][(1,2,3,4-η-naphthalene]ferrate(−I

    William W. Brennessel


    Full Text Available The title salt, [K(C12H24O6][Fe(C8H12(C10H8], is the only known naphthalene complex containing iron in a formally negative oxidation state. Each (naphthalene(1,5-codferrate(−I anion is in contact with one (18-crown-6potassium cation via K...C contacts to the outer four carbon atoms of the naphthalene ligand (cod = 1,5-cyclooctadiene, 18-crown-6 = 1,4,7,10,13,16-hexaoxacyclooctadecane. When using the midpoints of the coordinating olefin bonds, the overall geometry of the coordination sphere around iron can be best described as distorted tetrahedral. The naphthalene fold angle between the plane of the iron-coordinating butadiene unit and the plane containing the exo-benzene moiety is 19.2 (1°.

  15. Biomimetic cationic polyannulation reaction catalyzed by Bi(OTf)3: cyclization of 1,6-dienes, 1,6,10-trienes, and aryl polyenes.

    Godeau, Julien; Olivero, Sandra; Antoniotti, Sylvain; Duñach, Elisabet


    Nonactivated trienes and aryltrienes were cyclized into polycyclic compounds in good to excellent yields under bismuth triflate catalysis in a biomimetic fashion. The reaction showed broad applicability and allowed for the formation of functionalized bicyclic to tetracyclic structures from simple precursors in one pot. For some specific substrates, the cyclization was followed by a methyl shift as encountered in terpenoid biosynthesis.

  16. CCDC 935381: Experimental Crystal Structure Determination : Chloro-(eta^2^,eta^2^-cyclo-octa-1,5-diene)-(1-cyclopentyl-3-mesitylimidazol-2-ylidene)-rhodium

    Queval, Pierre


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

  17. Effect of chronic aluminum exposure on the levels of conjugated dienes and enzymatic antioxidants in hippocampus and whole brain of rat

    Gupta, A.; Shukla, G.S. [Industrial Toxicology Research Centre, Lucknow (India)


    The reported association between elevated tissue levels of aluminum (Al) and certain human neurological disorders have evoked increasing attention on the neurotoxic effects of aluminum. High levels of Al have been reported in hippocampal neurons comprising neurofibrillary tangles in senile dementia of Alzheimer`s type, amyotropic lateral sclerosis and Parkinsonian dementia of Guam. Aluminum is considered to be the causal factor for a high incidence of dialysis encephalopathy. It has been shown that the incidence of Alzheimer`s disease was higher in places with a high Al content in drinking water compared to low level areas. Varied uses of Al in pharmaceutical preparations, foods, water purification and many house-hold items have increased the risk of its exposure to general population. The exposure may be as high as 500 mg/kg/day in children with uremia who are treated with Al containing phosphate binding gels. Aluminum ingestion in humans and experimental animals have been reported to produce behavioural dysfunctions. The mechanism of al neurotoxicity is not understood at present. Attempts made in this direction have reported its interaction with blood-brain barrier function, decreased membrane fluidity, glutathione depletion and increased brain lipid peroxidation. These studies indicate the possibility that oxidative stress may be one of the possible mechanisms of Al-induced neurotoxicity. Since Al has been reported to be in high concentrations in hippocampal neurons in certain neurological diseases and there is wealth of evidence implicating hippocampal impairment and memory dysfunction, we attempted to investigate the effect of chronic Al intoxication on the status of enzymatic antioxidants and the extent of peroxidative damage in hippocampus and whole brain of rat. 16 refs., 4 figs., 1 tab.

  18. Molybdenum 1,4-diazabuta-1,3-diene tricarbonyl solvento complexes revisited: from solvatochromism to attractive ligand-ligand interaction.

    Oelkers, Benjamin; Venker, Alexander; Sundermeyer, Jörg


    Various complexes of the types [Mo(DAD)(CO)(3)L] (L = CO, MeCN, MeOH, THF, DMSO, DMF, Me(2)CO, EtOAc, THT, Im(H), Im(1), tBuNC, nBu(3)P), (ER(4))[Mo(DAD)(CO)(3)X] (ER(4) = NEt(4)(+); X(-) = Cl(-), Br(-), I(-), NCS(-), CN(-) and ER(4)(+) = PPh(4)(+); X(-) = N(3)(-)), and (ER(4))[{Mo(DAD)(CO)(3)}(2)(μ-X)] (ER(4)(+) = NEt(4)(+); X(-) = CN(-), OAc(-) and ER(4)(+) = PPh(4)(+); X(-) = N(3)(-); DAD = N,N'-bis(2,6-dimethylphenyl)butane-2,3-diimine) were prepared by ligand exchange from cycloheptatriene molybdenum tricarbonyl. A total of 19 crystal structures were determined, including unprecedented structural characterization of molybdenum(0) coordination by dimethyl sulfoxide (DMSO), methanol, ethyl acetate (EtOAc), acetone, and N,N-dimethylformamide (DMF). Correlation of (13)C NMR shifts with the complex geometry suggests a direct ligand-ligand interaction between DAD and O-bonded coligands with C═O and S═O double bonds, such as EtOAc, Me(2)CO, DMF, and DMSO. Unexpectedly, the solvatochromic properties of these tricarbonyl complexes [Mo(DAD)(CO)(3)L] are unfavorable for the determination of Kamlet-Taft parameters of the corresponding solvent L. Contrastingly, the UV/vis absorption of [Mo(DAD)(CO)(4)] is strongly correlated with the Kamlet-Taft parameter π*, which is shown for 22 solvents, including seven room temperature ionic liquids.

  19. (1S,2S,4R-3,3-Dichloro-4,8,12,12-tetramethyltricyclo[,4]dodeca-6,8-diene

    Ahmed Benharref


    Full Text Available The title compound, C16H22Cl2, a derivative of β-himachalene, was semi-synthesized from natural essential oils of Cedrus atlantica. The molecule is built up from two fused six- and seven-membered rings. The six-membered ring has a perfect chair conformation, whereas the seven-membered ring displays a screw boat conformation; the dihedral angle between the rings is 46.48 (9°.

  20. Synthesis and Spectroscopic Studies of Mixed Ligand Complexes of Pt(II and Pd(II with Ethyl-α-Isonitrosoacetoacetate and Dienes

    Anita Krishankant Taksande


    Full Text Available The mixed ligand complexes of the kind [M(L1 (L2] where M= Pt(II, Pd(II.L1 = primary ligand ethyl-α-isonitrosoacetoacetate derived from reaction between ethyl acetoacetate, acetic acid and sodium nitrite and L2=secondary ligand para-phenyldiamine (PPD are synthesized. All the prepared complexes were identified and confirmed by elemental analysis, molar conductance measurements, and infrared electronic absorption. Their complexes has been made based on elemental analysis, molar conductivity, UV-Vis, FT-IR and 1HNMR spectroscopy and magnetic moment measurements as well as thermal analysis (TGA and DTA. The elemental analysis information recommends that the stoichiometry of the complexes to be 1:2:1. The molar conductance measurements of the complexes indicate their non-electrolytic nature. The infrared spectral information showed the coordination sites of the free ligand with the central metal particle. The electronic absorption spectral information disclosed the existence of an octahedral geometry for Pt(II and Pd(II complexes. DOI: 

  1. Antihyperlipidemic effect of bis-1,7-(2-hydroxyphenyl)-hepta-1,6-diene-3,5-dione, a curcumin analog, on nicotine and streptozotocin treated rats.

    Reddy, Bandugula Venkata; Sivagama Sundari, J; Balamurugan, Elumalai; Menon, Venugopal Padmanabhan


    Diabetes and smoking have been considered as major health problems individually and their seriousness related to health hazard has been well reported. Data regarding the possible contribution of cigarette smoking to the development of diabetes are scarce and inconclusive. The aim was to investigate the effect of nicotine on diabetes and to analyze the effect of bis demethoxy curcumin analog (BDMCA) in streptozotocin (STZ) and nicotine-induced toxicity. The tissue lipids were extracted according to the method of Folch et al. Plasma and tissue cholesterol was estimated by the method of Allain et al. using reagent kit. Triglycerides were estimated by the method of Foster and Dunn. Free fatty acids were estimated by the method of Falholt et al. Tissue phospholipids were estimated by the method of Zilversmit and Davis. From our study, we found that nicotine not only aggravates diabetic complications but also increased the risk for diabetes. BDMCA, at a dose 80 mg/kg body weight was found to be effective in decreasing toxic effects induced by nicotine and STZ. Our data provide new evidence that cigarette smoking is an additional important factor that could be targeted for the prevention of diabetic complications.

  2. Solvent effects on a Diels-Alder reaction involving a cationic diene: Consequences of the absence of hydrogen-bond interactions for accelerations in aqueous media

    van der Wel, Gerben K.; Wijnen, Jan W.; Engberts, Jan B.F.N.


    In order to study the influence of hydrogen-bond interactions on the accelerations of Diels-Alder reactions in water and highly aqueous mixed solvent systems, second-order rate constants for the Diels-Alder reaction of acridizinium bromide (1a) with cyclopentadiene (CP) have been measured in aqueous

  3. Solvent effects on a Diels-Alder reaction involving a cationic diene : Consequences of the absence of hydrogen-bond interactions for accelerations in aqueous media

    Wel, Gerben K. van der; Wijnen, Jan W.; Engberts, Jan B.F.N.


    In order to study the influence of hydrogen-bond interactions on the accelerations of Diels-Alder reactions in water and highly aqueous mixed solvent systems, second-order rate constants for the Diels-Alder reaction of acridizinium bromide (1a) with cyclopentadiene (CP) have been measured in aqueous

  4. 40 CFR 721.6900 - Polymer of bisphenol A di-glyc-i-dal ether, substituted al-kenes, and but-a-diene.


    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Polymer of bisphenol A di-glyc-i-dal... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.6900 Polymer of bisphenol A di-glyc-i... subject to reporting. (1) The chemical substances identified generically as polymer of bisphenol A...

  5. Characterization of identity, metabolism and androgenic activity of 17-hydroxyandrosta-3,5-diene by GC-MS and a yeast transactivation system.

    Bauer, Anne; Rataj, Felicitas; Zierau, Oliver; Anielski, Patricia; Große, Joachim; Parr, Maria-Kristina; Vollmer, Günter; Thieme, Detlef


    Anabolic-androgenic steroids are frequently misused compounds in sports, and they belong to the controlled substances according to the requirements of the World Anti-Doping Agency. The classical techniques of steroid detection are mass spectrometry coupled to gas or liquid chromatography. Biological methods that base on the ability of substances to bind the steroid receptor are not applied in routine doping control procedures so far, but they appear to be useful for characterization of steroid androgenic potential. In this study we used the yeast androgen receptor reporter system (YAS), which in the past has already successfully been applied to both various androgenic substances and also urine samples. Giving attention to the androgenic potential of steroidal dietary supplements, we exemplified the analysis using both mass spectrometry techniques and the YAS-based assay on the product "Syntrax Tetrabol" which was a confiscated dietary supplement and marketed as a steroid precursor. Identification, structure and the kinetic behavior of its excreted metabolites were analyzed by NMR, GC-MS and LC-MS/MS. The androgenic potential of the parent compound as well as its metabolites in urine was evaluated with the help of the YAS. The application of urine samples with a previous deconjugation and the inclusion of urine density values were carried out and led to increased responses on the YAS. Further, the possibility of a complementary application of structure-based instrumental analysis and biological detection of androgenicity with the help of the YAS seems to be desirable and is discussed.

  6. [1,1'-Bis(dicyclo-hexyl-phosphino)cobalto-cenium-κP,P']chlorido(η-cyclo-penta-dien-yl)ruthenium(II) hexa-fluorido-phosphate.

    Hou, Jian-Guo


    In the title structure, [CoRu(C(5)H(5))(C(17)H(26)P)(2)Cl]PF(6), the Ru(II) atom is bonded to a cyclo-penta-dienyl ring, a Cl atom and two P atoms of the chelating 1,1'-bis-(dicyclo-hexyl-phosphino)cobaltocenium (di-cypc) ligand, leading to a three-legged piano-stool coordination. Part of the PF(6) (-) counter-anion is disordered over two positions, with a site-occupancy ratio of 0.898 (7):0.102 (7). The components are linked by C-H⋯F and C-H⋯Cl hydrogen bonds.

  7. Les angles rétro-glénoïdiens et homologues du rachis cervical supérieur des primates actuels

    Gommery, Dominique


    The posterior part of the atlas superior articular processes ( foveae articulares superiores atlantis) or the retro-glenoid tubercles, as well as those of the atlas inferior facet ( foveae articulares inferiores atlantis) and of the axis superior facet ( facies articularis superior axis), have permitted the retro-glenoid and homologous angle to be defined. These angles have a major systematic importance in individualizing four extant primates groups: Strepsirhini, Platyrrhini and Cercopithecoidea non-humans Hominoidea, and man. This angle permits a better functional and static definition of the superior cervical column, the head being in balanced or unbalanced unstable position.

  8. Metabolic engineering of E.coli for the production of a precursor to artemisinin, an anti-malarial drug [Chapter 25 in Manual of Industrial Microbiology and Biotechnology, 3rd edition

    Petzold, Christopher; Keasling, Jay


    This document is Chapter 25 in the Manual of Industrial Microbiology and Biotechnology, 3rd edition. Topics covered include: Incorporation of Amorpha-4,11-Diene Biosynthetic Pathway into E. coli; Amorpha-4,11-Diene Pathway Optimization; "-Omics" Analyses for Increased Amorpha-4,11-Diene Production; Biosynthetic Oxidation of Amorpha-4,11-Diene.


    STOELWINDER, J; van Leusen, A.M.


    The synthesis is described of a series of polyfunctional unsaturated DELTA16,20-20-isocyanosteroids 5a-f by the Wittig-Horner-Emmons reaction of (E)-17-[(diethylphosphono)isocyanomethylene] steroid 4 with several aldehydes and with acetone. Hydrolysis of the isocyanosteroids 5a-f with dilute sulfuri

  10. 3,11(13)-二烯-12-桉烷酸的立体选择性全合成%Enantioselective Total Synthesis of 12-Carboxyeudesma-3,11(13)-diene

    周罡; 陈永刚; 关玉昆; 郑国君; 李裕林


    桉烷型倍半萜类化合物广泛分布于天然植物中, 此类化合物多具有较好的生理活性, 其中桉烷酸类化合物因具有广泛的生物活性而受到重视. 例如, 3,11(13)-二烯-12-桉烷酸(1)呈现较好的抗菌活性[1], 桉烷酸(2)具有消炎退热的活性[2]. 3,11(13)-二烯-12-桉烷酸(1)是Shtacher等[1]从地中海草药Inula viscosa Ait中分离得到的. 其合成工作尚未见文献报道.

  11. Priešistorinių ir senovės pasaulio sakralinių kompleksų šių dienų apsaugos ir panaudos iššūkiai

    Zina Masilionytė


    Full Text Available Kraštotvarkos ir urbanistikos mokslai daug dėmesio skiria viešosioms erdvėms – aikštėms, skverams, parkams, gatvės erdvėms, jų funkcionavimui ir įtakai urbanistinei struktūrai. Visgi sakralinių kompleksų kraštovaizdyje ir miestovaizdyje formuojamos erdvės, jų specifinių paskirčių veikiama evoliucija ir šiandieninės panaudos bei apsaugos klausimai ne visada sulaukia išskirtinio dėmesio. Šiame straipsnyje pristatomos sakralinių kompleksų vystymosi ištakos ir šiandieninės visuomenės santykis su jų medžiaginiu palikimu. Siekiant suprasti sakralinių kompleksų raidos, funkcionavimo, pritaikymo, saugojimo, plėtros, santykio su aplinka aspektus analizuojami priešistoriniai ir senovės pasaulio sakraliniai kompleksai. Analizė apima trijų laikotarpių ir kultūrų sakralinius kompleksus bei jų užuomazgas: pirmykštes sakralias vietas ir jų įprasminimą, Mesopotamijos ir Senovės Egipto monumentaliuosius religinius kompleksus ir klasikinio pasaulio – Senovės Graikijos – visuomeninius sakralinius centrus.Straipsnis lietuvių kalba

  12. 二乙三胺、三乙四胺钴配合物氧合作用的研究%Oxygenation of Dien,Trien-Co(Ⅱ) Complexes

    岳凡; 王吉德; 崔勇; 张旭龙; 李兴寿


    The equilibrium constants and oxygenation constants of diethylenetriamine,trieth ylenettramine-Co(Ⅱ) complex were determined by pH potentionmetric method.Some new oxygenated species and their oxygenation constants were found.The oxygenated species and their formation conditions investigated by potentiometry were verif ied by spectrophotometry.Results of the two methods were consistant with one ano ther very well showing the correctness of the results of potentiometry.

  13. 活性预处理三元乙丙橡胶/天然橡胶并用胶的性能%Properties of active pretreated ethylene-propylene-diene rubber/natural rubber blends

    齐兴国; 王进; 杨军; 刘光烨



  14. Properties of ethylene propylene diene monomer co-crosslinking modified with epoxy natural rubber/natural rubber blends%环氧化天然橡胶共交联改性EPDM/NR共混物的性能

    陈福林; 杨坤民; 岑兰; 周彦豪



  15. A retro Diels-Alder route to diphosphorus chemistry: molecular precursor synthesis, kinetics of P2 transfer to 1,3-dienes, and detection of P2 by molecular beam mass spectrometry.

    Velian, Alexandra; Nava, Matthew; Temprado, Manuel; Zhou, Yan; Field, Robert W; Cummins, Christopher C


    The transannular diphosphorus bisanthracene adduct P2A2 (A = anthracene or C14H10) was synthesized from the 7-phosphadibenzonorbornadiene Me2NPA through a synthetic sequence involving chlorophosphine ClPA (28-35%) and the tetracyclic salt [P2A2Cl][AlCl4] (65%) as isolated intermediates. P2A2 was found to transfer P2 efficiently to 1,3-cyclohexadiene (CHD), 1,3-butadiene (BD), and (C2H4)Pt(PPh3)2 to form P2(CHD)2 (>90%), P2(BD)2 (69%), and (P2)[Pt(PPh3)2]2 (47%), respectively, and was characterized by X-ray diffraction as the complex [CpMo(CO)3(P2A2)][BF4]. Experimental and computational thermodynamic activation parameters for the thermolysis of P2A2 in a solution containing different amounts of CHD (0, 4.75, and 182 equiv) have been obtained and suggest that P2A2 thermally transfers P2 to CHD through two competitive routes: (i) an associative pathway in which reactive intermediate [P2A] adds the first molecule of CHD before departure of the second anthracene, and (ii) a dissociative pathway in which [P2A] fragments to P2 and A prior to addition of CHD. Additionally, a molecular beam mass spectrometry study on the thermolysis of solid P2A2 reveals the direct detection of molecular fragments of only P2 and anthracene, thus establishing a link between solution-phase P2-transfer chemistry and production of gas-phase P2 by mild thermal activation of a molecular precursor.

  16. Absorption spectra and photochemical rearrangements of C/sub 8/H/sub 10/ cations in solid argon. Bicyclo(2. 2. 2)octa-2,5-diene, cycloocta-1,3,5-triene, and octatetraene

    Dunkin, I.R.; Andrews, L.; Lurito, J.T.; Kelsall, B.J.


    Matrix photoionization experiments with bicyclooctadiene and cyclooctatriene gave sharp new bands between 400 and 500 nm. Selective photolysis with visible light decreased the longer wavelength absorptions and increased a band system beginning at 447 nm; irradiation at 420-470 nm essentially restored the original spectrum. Photoionization of all-trans-octatetraene directly produced a strong 447-nm band system and a sharp weaker 756-nm band system; the latter origin and vibrational structure are in excellent agreement with the emission spectrum of the gaseous cation. Cyclooctatriene and bicyclooctadiene cations experienced a series of photochemical rearrangements, which initially gave a mixture of trans- and cis-octatetraene cations that were converted to all-trans-octatetraene cation by selective irradiation in the solid argon matrix. 23 references, 4 figures, 3 tables.

  17. Antinephrotoxic efficacy of Operculina turpethum and its isolated Stigma-5,22dien-3-O-b-D-glucopyranoside against N-Nitrosodimethylamine induced renal carcinogenesis in male mice

    Veena Sharma


    Full Text Available Objectives: Human exposure to nitrosamines can result from the formation of N‑nitroso compounds either in food during storage or preparation or in vivo, usually in the stomach. N-Nitrosodimethylamine (NDMA is one of the main N-nitroso compounds which is commonly found in drinking water and is a potent carcinogen. The therapeutic effect of ethanolic root extract of Operculina turpethum was studied for its possible anti-cancerous potential induced by N- Nitrosodimethylamine in male albino mice as the in vivo model for the study.Methods: Renal malondialdehyde (MDA, Superoxide dismutase (SOD, catalase (CAT, glutathione content (GSH, aspartate aminotransferase (AST, alanine aminotransferase (ALT, alkaline phosphatase (ALP, protein, cholesterol, urea and creatinine content were measured as oxidant/antioxidant markers. Electron Microscopy investigations of the renal tissue were also performed. One-way ANOVA test was used for comparisons of parameters in study groups.Results: Renal antioxidant defense systems, such as superoxide dismutase, catalase, glutathione peroxidase activities and reduced glutathione level, depleted by NDMA were restored to normal by the treatment. Oral administration of Operculina turpethum ethanolic extract, both crude and isolated groups recovered the enzyme activities and caused significant increase in serum protein, the treatment significantly reduced the elevated serum creatinine and urea levels (p>0.05, (p<0.01, (p<0.001. The ultrastructural electron microscopical analysis showed a decrease in cellular degradation comparing to the intoxicated mice.Conclusion: These findings prove the potential of Operculina turpethum as an antioxidant therapy to counteract mitochondrial and post-mitochondrial oxidative stress generated in kidney upon NDMA treatment thereby acting against renal toxicity by a carcinogen.

  18. Analysis on the International Impact of the Battle Dien Bien Phu in 1954%1954年奠边府战役的国际影响分析




  19. 写不尽的奠边情怀--记越南五位军旅老作家%Unforgettable Feelings Towards Dien Bien Phu Battle in Vietnam:An Interview with five Military Writers



    @@ 奠边府战役是越军在抗法战争中发动的一次最大的兵种协同战役,为粉碎"纳瓦尔计划"和美国的干涉作出了决定性贡献.奠边府战役的胜利对赢得抗法战争的全面胜利具有决定性意义.

  20. 1,1'-[(1E,11E)-5,8-Dioxa-2,11-diazo-nia-dodeca-1,11-diene-1,12-di-yl]dinaph-thal-en-2-olate.

    Liu, Yanju; Liu, Kai; Cao, Zhiqiang; Niu, Meiju


    The title compound, C(28)H(28)N(2)O(4), crystallizes in a zwitterionic form with deprotonated naphthol hy-droxy groups and protonated imine N atoms. The asymmetric unit contains one half-mol-ecule located on a twofold rotation axis. Intra-molecular N-H⋯O hydrogen bonds occur and the two bicyclic ring systems form a dihedral angle of 64.2 (1)°. In the crystal, weak inter-molecular C-H⋯O hydrogen bonds link the mol-ecules into layers parallel to the bc plane.

  1. Study on Nucleophilic Additions to endo-tricyclo[5.2.1.O2.6]deca-2(6),8-dien-3-one and an Unusual Payne Rearrangementof α, β-Epoxy Tricyclodecenone


    Synthesis of highly strained tetracyclic ketones was achieved by cyclopropanation or epoxidation of tricyclodecenone 1. An unusual formation of α-methoxy β-hydroxy ketone from an α,β-unsaturated enone system via Payne rearrangement was reported.

  2. Protective Effects of 2-Dodecyl-6-Methoxycyclohexa-2,5 -Diene-1,4-Dione Isolated from Averrhoa Carambola L. (Oxalidaceae) Roots on High-Fat Diet-Induced Obesity and Insulin Resistance in Mice.

    Li, Juman; Wei, Xiaojie; Xie, Qiuqiao; Hoa Pham, Thi Thai; Wei, Jinbin; He, Ping; Jiao, Yang; Xu, Xiaohui; Giang Nguyen, Thi Huong; Wen, Qingwei; Huang, Renbin


    The roots of Averrhoa carambola L. (Oxalidaceae) have long been used as a traditional Chinese medicine for the treatment of diabetes and diabetes-related diseases. 2-dodecyl-6-methoxycycyclohexa-2,5-1,4-dione (DMDD) has been isolated from A. carambola L. roots, and this study was carried out to investigate the potential beneficial effects of DMDD on obesity and insulin resistance induced by a high-fat diet (HFD) in mice. C57BL/6J mice were fed a HFD for 16 weeks and orally administered DMDD (12.5, 25, or 50 mg/kg of body weight per day) and metformin (280 mg/kg of body weight per day) for the last 4 weeks. The body weights and adipose tissue weights as well as the serum levels of blood glucose, total cholesterol, triglycerides, free fatty acids, insulin, interleukin-6, and tumor necrosis factor-α were significantly decreased by DMDD, and the expression of Toll-like receptor 4 (TLR4) and myeloid differentiation factor (Myd88) in the epididymal adipose tissue was downregulated by DMDD. In contrast, insulin sensitivity was enhanced. The results of the glucose tolerance tests, insulin tolerance tests, and insulin release tests indicated that there was a marked improvement in insulin secretion, and the areas under the curve corresponding to the three tests were also significantly decreased by DMDD. The activities of superoxide dismutase and glutathione peroxidase were simultaneously enhanced, whereas the content of malondialdehyde was decreased by DMDD in the liver homogenates of the C57BL/6J mice. In addition, hepatic steatosis and adipocyte hypertrophy, as assessed by H&E staining of liver and adipose tissues, were significantly improved by DMDD. These data suggest that MDD has potential benefits for the treatment of HFD-induced obesity and insulin resistance, and its effects may be associated with improvements in lipid metabolism and inhibition of the expression of TLR4 in adipose tissues. © 2016 The Author(s) Published by S. Karger AG, Basel.

  3. (1S,2S,4R)-3,3-Dichloro-4,8,12,12-tetra­methyl­tricyclo­[,4]dodeca-6,8-diene

    Benharref, Ahmed; El Ammari, Lahcen; Berraho, Moha; Lassaba, Esaadia


    The title compound, C16H22Cl2, a derivative of β-himachalene, was semi-synthesized from natural essential oils of Cedrus atlantica. The mol­ecule is built up from two fused six- and seven-membered rings. The six-membered ring has a perfect chair conformation, whereas the seven-membered ring displays a screw boat conformation; the dihedral angle between the rings is 46.48 (9)°. PMID:21588782

  4. (1S,2S,4R)-3,3-Dichloro-4,8,12,12-tetra-methyl-tricyclo-[]dodeca-6,8-diene.

    Benharref, Ahmed; El Ammari, Lahcen; Berraho, Moha; Lassaba, Esaadia


    The title compound, C(16)H(22)Cl(2), a derivative of β-himachalene, was semi-synthesized from natural essential oils of Cedrus atlantica. The mol-ecule is built up from two fused six- and seven-membered rings. The six-membered ring has a perfect chair conformation, whereas the seven-membered ring displays a screw boat conformation; the dihedral angle between the rings is 46.48 (9)°.

  5. CCDC 1433194: Experimental Crystal Structure Determination : (1-(2-cyclohexyl-1-naphthyl)-3-(2-cyclohexyl-1-naphthyl)imidazolidin-2-ylidene)-(eta2,eta2-cycloocta-1,5-diene)-iridium hexafluorophosphate

    Sipos, Gellért


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

  6. CCDC 1433196: Experimental Crystal Structure Determination : (eta2,eta2-cycloocta-1,5-diene)-(1-(2,7-dicyclohexyl-1-naphthyl)-3-(2,7-dicyclohexyl-1-naphthyl)imidazolidin-2-yl-dene)-iridium hexafluorophosphate dichloromethane solvate

    Sipos, Gellért


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

  7. CCDC 1433192: Experimental Crystal Structure Determination : (1,3-bis(2,7-dicyclohexyl-1-naphthyl)imidazolidin-2-ylidene)-chloro-(eta2,eta2-cycloocta-1,5-diene)-iridium dichloromethane solvate

    Sipos, Gellért


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

  8. 7-Isopropylidene-N2,N3,N5,N6-tetramethoxy-N2,N3,N5,N6-tetramethylbicyclo[2.2.1]hepta-2,5-diene-2,3,5,6-tetracarboxamide

    Benjamin Sahlmann


    Full Text Available Although the molecular structure of the title compound, C22H32N4O8, displays a twofold symmetry of the molecule including the methoxy and methyl substituents, no crystallographic twofold symmetry is observed in the X-ray structure analysis. The carbonyl O atoms alternately point to different sides of the plane defined by the carbonyl C atoms. Two methoxy groups are oriented inside the molecules cavity. The H atoms of two methyl groups are disordered over two orientations and were refined using a split model.

  9. Procédés d'oxydation avancée pour l’élimination d’anti-inflammatoires non-stéroïdiens résiduels présents en milieux aqueux

    Feng, Ling


    The thesis mainly focused on the implementation of advanced oxidation processes for the elimination of three non-steroidal anti-inflammatory drugs-ketoprofen, naproxen and piroxicam in waters. The three compounds are among the most used medicines, whose presence in waters poses a potential ecotoxicological risk. Due to the low pharmaceuticals removal efficiency of traditional wastwater treatement plants, worldwide concerns and calls are raised for efficient and eco-friendly technologies. Adva...

  10. CCDC 1005757: Experimental Crystal Structure Determination : (mu2-eta5,eta5-Bi-cyclohexa-2,4-dien-1-yl)-bis(eta5-pentamethyl-cyclopentadienyl)-di-iron

    Mohapatra, Swagat K.


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

  11. CCDC 1005758: Experimental Crystal Structure Determination : (mu2-eta5,eta5-Bi-(2,4,6-triethylcyclohexa-2,4-dien-1-yl))-bis(eta5-pentamethyl-cyclopentadienyl)-di-ruthenium

    Mohapatra, Swagat K.


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

  12. Kerklike tradisie en kultuur as bydraende faktore in die diens aan die Koninkryk – die lewe en werk van dominee Kálmán Papp II (geb. 1924

    Kálmán D. Papp


    Full Text Available Church tradition and culture as contributory factors in service to the Kingdom. This study describes how reverend Kálmán Papp (1924– was able to leave his land of origin behind under difficult, unasked-for and compelling circumstances and embrace a new future in a far-off and unknown country. This follows from his spontaneous responding and acting positively to the effects of cultural interaction and the common denominational factor of the Reformed Church ever present. The study argues in its methodology that it is an oversimplification and a mistake to seek truth by avoiding, underestimating or eliminating the necessary outcome of cultural interaction and church tradition in the choices we make (even theologically and experiences we have of life. This is the true life story of a church minister who finds his destiny and becomes himself a minister in the service of God’s Kingdom, through faith’s challenges and encounters with the theologies and cultures of his embracing worlds.

  13. [1,1′-Bis(dicyclo­hexyl­phosphino)cobalto­cenium-κ2 P,P′]chlorido(η5-cyclo­penta­dien­yl)ruthenium(II) hexa­fluorido­phosphate

    Hou, Jian-Guo


    In the title structure, [CoRu(C5H5)(C17H26P)2Cl]PF6, the RuII atom is bonded to a cyclo­penta­dienyl ring, a Cl atom and two P atoms of the chelating 1,1′-bis­(dicyclo­hexyl­phosphino)cobaltocenium (di-cypc) ligand, leading to a three-legged piano-stool coordination. Part of the PF6 − counter-anion is disordered over two positions, with a site-occupancy ratio of 0.898 (7):0.102 (7). The components are linked by C—H⋯F and C—H⋯Cl hydrogen bonds. PMID:21579679

  14. 奠边府战役的胜利:中越人民战斗友谊的历史丰碑——奠边府战役胜利60周年纪念%Victory of Battle of Dien Bien Phu: A Brilliant History of China-Vietnam Solidarity Battle——for 60 anniversary of victory in Battle of Dien Bien Phu




  15. Photolytic Cleavage and Condensation Reactions of Cyclohexa-2,4-dienones with Diamines

    Sung Kee Chung


    Full Text Available Cyclohexa-2,4-diene-1-one sulfone derivate undergoes ring cleavage to afford bis-amides containing a diene moiety on irradiation with visible light in the presence of various diamines.

  16. Triterpenos da resina de Protium heptaphyllum March (B0urseraceae: caracterização em misturas binárias

    Maia Robinson Magalhães


    Full Text Available Eight triterpenes, maniladiol, breine, ursa-9(11:12-dien-3beta-ol, oleana-9(11:12-dien-3beta-ol, 3alpha-hydroxy-tirucalla-8,24-dien-21-oic acid, 3alpha-hydroxy-tirucalla-7,24-dien-21-oic, alpha and beta amyrines were isolated as binary mixtures obtained from the chloroform extract of the oil-resin of Protium heptaphyllum March. The identification of the compounds was based mainly in 13C NMR data and mass spectra. The diene and the tetracyclic acid triterpenes were not reported before in the literature as constituents of the studied resin.

  17. Δ2-Triterpenes: Early intermediates in the diagenesis of terrigenous triterpenoids

    ten Haven, H. L.; Peakman, T. M.; Rullkötter, J.


    A series of Δ2-triterpenoids (oleana-2,12-diene, oleana-2,13(18)-diene, oleana-2,18-diene, ursa-2, 12-diene, and taraxera-2,14-diene) has been identified in Holocene buried mangrove sediments (Florida, USA) by comparison of the mass spectra of and by co-injections with authentic standards. In the Oligocene Brandon lignite (Vermont, USA) oleana-2,12-diene and oleana-2,13(18)-diene were also identified, along with two A-ring contracted amyrin derivatives. By comparison with the sedimentary occurrence of related analogues of oxyallobetulin and betulin and the demonstrated diagenetic formation of lup-2-ene from lupan-3-one, these novel terrigenous biological markers are considered diagenetic products formed by dehydration of precursor molecules, such as α- and β-amyrin, and taraxerol. The identification of these early intermediates brings us one step closer to the full understanding of the diagenetic fate of terrigenous triterpenoids.

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

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


    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.

  19. Diversity-Oriented Approaches to Polycyclics and Bioinspired Molecules via the Diels-Alder Strategy: Green Chemistry, Synthetic Economy, and Beyond.

    Kotha, Sambasivarao; Chavan, Arjun S; Goyal, Deepti


    We describe diverse approaches to various dienes and their utilization in the Diels-Alder reaction to produce a variety of polycycles. The dienes covered here are prepared by simple alkylation reaction or via the Claisen rearrangement or by enyne metathesis of alkyne or enyne building blocks. Here, we have also included the Diels-Alder chemistry of dendralenes, a higher analog of cross-conjugated dienes. The present article is inclusive of o-xylylene derivatives that are generated in situ starting with benzosultine or benzosulfone derivatives. The Diels-Alder reaction of these dienes with various dienophiles gave diverse polycyclic systems and biologically important targets.

  20. 原位改性三元乙丙橡胶炭黑混炼胶与天然橡胶共混胶的性能%Properties of blends of in-situ modified carbon black loaded ethylene- proplylene-diene rubber and natural rubber

    齐兴国; 李荣勋; 王进; 杨军; 刘光烨



  1. "奠边府战役暨日内瓦会议50周年国际学术研讨会"简介%A Brief Introduction to the International Symposium on the 50 Anniversary of the Dien Bien Phu Campaign and the Geneva Conference



    @@ 最近,由北京大学东南亚学研究中心和郑州大学越南研究所联合举办的"奠边府战役暨日内瓦会议50周年国际学术研讨会"在北京举行,中、越、法三国30余名专家学者及历史见证人参加会议.

  2. Friendship and Solidarity of People between China and Vietnam is Invincible——Historical Revelation from Border Battle to Dien Bien Phu Victory%中越两国人民的友谊和团结是不可战胜的——从边界战役到奠边府大捷的历史启示




  3. China's Predominant Contributions to the Victory of the Battle of Dien Bien Phu and the Signing of Geneva Agreements%中国对奠边府战役胜利和日内瓦协议签署的卓越贡献




  4. 云南人民对越南抗法战争的支援:几个史实--奠边府战役暨《日内瓦协议》签署50周年纪念%The Yunnan Peoples'Assistance to Against - French War in Vietnam:The 50th Aniversary of Victory in Dien Bien Phu War



    @@ 云南是中国西南地区一个多民族的边疆省份,与越南山水相连,共同边界长达1 353公里,双方间有铁路、公路、水路、航空等立体交通网络相通,是我国通往越南的两个重要桥头堡之一.滇越之间有多个民族跨界而居,自古以来就有着密切的政治、经济、文化交往.

  5. Crystal structure of (1S,2R,6R,7R,8S,12S-4,10,17-triphenyl-15-thia-4,10-diazapentacyclo[,16.02,6.08,12]heptadeca-13,16-diene-3,5,9,11-tetrone p-xylene hemisolvate

    Wayland E. Noland


    Full Text Available The title tetrone compound, C32H22N2O4S· 0.5C8H10, is the major product (50% yield of an attempted Diels–Alder reaction of 2-(α-styrylthiophene with N-phenylmaleimide (2 equivalents in toluene. Recrystallization of the resulting powder from p-xylene gave the title hemisolvate; the p-xylene molecule is located about an inversion center. In the crystal, the primary tetrone contacts are between a carbonyl O atom and the four flagpole H atoms of the bicyclo[2.2.2]octene core, forming chains along [001].

  6. Forward extrusion simulation and invert die design of ethylene propylene-diene rubber in simple dies%三元乙丙橡胶在简单口型中的正向挤出分析及逆向口型设计

    戴元坎; 郭营; 俞炜; 周持兴



  7. Rearrangement of a (dithiolato)platinum(II) complex formed by reaction of cyclic disulfide 7,8-dithiabicyclo[4.2.1]nona-2,4-diene with a platinum(0) complex: Oxidation of the rearranged (dithiolato)platinum(II) complex

    石井, 昭彦


    Reaction of the title bicyclic disulfide 16 with [(Ph3P)(2)Pt(eta(2)-C2H4)] (2) yielded the corresponding (dithiolato)platinum(II) complex 17 by oxidative addition. The initial product 17 isomerized at room temperature in a [1,5]-sulfur rearrangement to give another (dithiolato)platinum(II) complex 18 in high isolated yield. Oxidation reactions of 18 with dimethyldioxirane (DMD) provided (sulfenato-thiolato)platinum(II) 23, (sulfinato-thiolato)platinum(II) 24, (sulfenato-sulfinato)platinum(II...

  8. [1,1'-Bis(di-phenyl-phosphan-yl)cobalto-cenium-κ(2) P,P'](η(5)-cyclo-penta-dien-yl){2-[4-(4-ethynylphen-yl)phen-yl]ethynyl-κC}ruthenium(II) hexa-fluorido-phosphate.

    Zeng, Ling-Zhen; Wu, Yun-Ying; Tian, Guang-Xuan; Li, Zhen


    In the title compound, [CoRu(C5H5)(C16H9)(C17H14P)2]PF6, the Ru(II) atom is coordinated by a cyclo-penta-dienyl ring in an η(5)-mode, one C atom from a 4,4'-diethynyl-1,1'-biphenyl ligand and two P atoms from a chelating 1,1'-bis-(di-phenyl-phosphan-yl)cobaltocenium ligand, giving a three-legged piano-stool geometry. In the crystal, weak C-H⋯F hydrogen bonds link the complex cations and hexa-fluorido-phosphate anions into a three-dimensional supra-molecular structure.

  9. [1,1′-Bis(di­phenyl­phosphan­yl)cobalto­cenium-κ2 P,P′](η5-cyclo­penta­dien­yl){2-[4-(4-ethynylphen­yl)phen­yl]ethynyl-κC}ruthenium(II) hexa­fluorido­phosphate

    Zeng, Ling-Zhen; Wu, Yun-Ying; Tian, Guang-Xuan; Li, Zhen


    In the title compound, [CoRu(C5H5)(C16H9)(C17H14P)2]PF6, the RuII atom is coordinated by a cyclo­penta­dienyl ring in an η5-mode, one C atom from a 4,4′-diethynyl-1,1′-biphenyl ligand and two P atoms from a chelating 1,1′-bis­(di­phenyl­phosphan­yl)cobaltocenium ligand, giving a three-legged piano-stool geometry. In the crystal, weak C—H⋯F hydrogen bonds link the complex cations and hexa­fluorido­phosphate anions into a three-dimensional supra­molecular structure. PMID:24454037

  10. Oplysningstiden

    Thomsen, Viggo Ernst


    Kapitlet beskriver pietismen og den britiske og franske oplysningstidstænkning i 1700-tallet (Locke,Hume,Montesquieu, Voltaire,Encyklopædien, Rousseau, Kant, Menneskerettighederne og arven fra oplysningstiden)......Kapitlet beskriver pietismen og den britiske og franske oplysningstidstænkning i 1700-tallet (Locke,Hume,Montesquieu, Voltaire,Encyklopædien, Rousseau, Kant, Menneskerettighederne og arven fra oplysningstiden)...

  11. LDL oxidative modification and carotid atherosclerosis : Results of a multicenter study

    Nyyssonen, K.; Kurl, S.; Karppi, J.; Nurmi, T.; Baldassarre, D.; Veglia, F.; Rauramaa, R.; de Faire, U.; Hamsten, A.; Smit, A. J.; Mannarino, E.; Humphries, S. E.; Giral, P.; Grossi, E.; Tremoli, E.


    Objective: Serum LDL conjugated diene concentration is a marker of oxidative modification of LDL. We investigated the relationship between LDL conjugated dienes and cross-sectional subclinical atherosclerosis assessed by carotid IMT in high-risk subjects of a multicenter study. Methods: Serum LDL co

  12. Enantioselective synthesis of helicenequinones and -bisquinones.

    Urbano, Antonio; Carreño, M Carmen


    A convergent approach based on Diels-Alder reactions between polycyclic dienes and benzoquinones has emerged as a powerful tool for the construction of helicenequinones and bisquinones. Chemical resolution and asymmetric Diels-Alder reactions with sulfinyl quinones provide direct access to enantiopure derivatives. Biaryl or ferrocenyl dienes can be resolved leading to helicenequinones having additional axial or planar chirality.

  13. Zinc mediated domino elimination-alkylation of methyl 5-iodopentofuranosides

    Hyldtoft, Lene; Poulsen, Carina Storm; Madsen, Robert


    5-Iodopentofuranosides are converted with zinc and allyl/propargyl bromide into dienes/enynes which are further used in carbohydrate annulation reactions.......5-Iodopentofuranosides are converted with zinc and allyl/propargyl bromide into dienes/enynes which are further used in carbohydrate annulation reactions....

  14. Military Review, January 1992. Volume 72, Number 1


    varre’s decision to name Colonel Christiana-Cmn Honque ’rmecn B M= Marie Ferdinand de la Croix de Castries asat Dien Sin Phu Gilles’ successor at...implementation of the Dien Bien Phu Cam- paign. French staff officers and commanders, graduates of Saint Cyr and the cole de Guerre , r ev w fAt amn smui veterans

  15. Sterols from the Lakshadweep sponge, Ircinia ramosa (Killer)

    Parameswaran, P.S.; Naik, C.G.; Das, B.; Kamat, S.Y.

    Four monohydroxy sterols, viz, (22E,24S)-24-methylcholest-5,22-dien-3(beta)-ol (3), cholesterol (4), 24(Xi)-ethylcholesterol (8) and the corresponding Delta super(4)-3 ketones, viz. (22E,24S)-24-methylcholest-4,22-dien-3-one (1), cholest-4-en-3-one...

  16. Misunderstanding the Operational Environment: Michigan State University and the South Vietnamese Civil Guard, 1955-1960


    Bien Phu and the start of the Geneva Conference, the political situation changed drastically. The French believed that a strong defense of Dien Bien ...besieged French troops at Dien Bien Phu.27 The French believed that Eisenhower’s decision not to act on the behalf of the French resulted in defeat

  17. First Records ofMegophrys daweimontis Rao and Yang, 1997 andAmolops vitreus (Bain, Stuart and Orlov, 2006) (Anura:Megophryidae, Ranidae) from Vietnam

    Dzung Trung LE; Anh Van PHAM; Son Hung Lan NGUYEN; Thomas ZIEGLER; Truong Quang NGUYEN


    Two amphibian species,Megophrys daweimontisandAmolops vitreus,are recorded for the ifrst time from Vietnam, on the basis of a new amphibian collection from Dien Bien and Son La provinces. In addition, acoustic analysis ofA. vitreus is also provided based on the advertisement calls recorded in Muong Nhe Nature Reserve of Dien Bien Province, Vietnam.

  18. Effect of third monomer type and content on the UV stability of EPDM

    Snijders, Emile A.; Boersma, Arjen; Baarle, van Ben; Noordermeer, Jacques


    Various uncompounded ethylene–propylene–diene (EPDM) elastomers were photo-oxidized using standard Weather-O-Meter (WOM) aging and oxygen absorption measurements during UV irradiation. The influence of the type and amount of diene on the UV stability was investigated. FTIR (ATR) measurements of the

  19. Preference of Ruthenium-Based Metathesis Catalysts toward Z- and E-Alkenes as a Guide for Selective Reactions to Alkene Stereoisomers.

    Lee, Jihong; Kim, Kyung Hwan; Lee, Ok Suk; Choi, Tae-Lim; Lee, Hee-Seung; Ihee, Hyotcherl; Sohn, Jeong-Hun


    As a guide for selective reactions toward either Z- or E-alkene in a metathesis reaction, the relative preference of metathesis Ru catalysts for each stereoisomer was determined by a method using time-dependent fluorescence quenching. We found that Ru-1 prefers the Z-isomer over the E-isomer, whereas Ru-2 prefers the E-isomer over the Z-isomer. The Z/E-alkene preference of the catalysts precisely predicted the Z/E isomeric selectivity in the metathesis reactions of diene substrates possessing combinations of Z/E-alkenes. For the diene substrates, the rate order of the reactions using Ru-1 was Z,Z-1,6-diene > Z,E-1,6-diene > E,E-1,6-diene, while the completely opposite order of E,E-1,6-diene > Z,E-1,6-diene > Z,Z-1,6-diene was exhibited in the case of Ru-2.

  20. Abraham Kuyper als theoloog

    W. H. Velema


    Full Text Available Men zou in Nederland de herdenking van Kuypers honderdvijftigste geboortedag hebben kunnen aangrijpen als een gelegenheid om diens theologie en diens levenswerk in kerk en samenleving te evalueren. Niemand kan ontkennen dat er in genoemde publicaties iets van een evaluatie is te vinden.

  1. Learning Non-Local Dependencies

    Kuhn, Gustav; Dienes, Zoltan


    This paper addresses the nature of the temporary storage buffer used in implicit or statistical learning. Kuhn and Dienes [Kuhn, G., & Dienes, Z. (2005). Implicit learning of nonlocal musical rules: implicitly learning more than chunks. "Journal of Experimental Psychology-Learning Memory and Cognition," 31(6) 1417-1432] showed that people could…

  2. Learning Non-Local Dependencies

    Kuhn, Gustav; Dienes, Zoltan


    This paper addresses the nature of the temporary storage buffer used in implicit or statistical learning. Kuhn and Dienes [Kuhn, G., & Dienes, Z. (2005). Implicit learning of nonlocal musical rules: implicitly learning more than chunks. "Journal of Experimental Psychology-Learning Memory and Cognition," 31(6) 1417-1432] showed that people could…

  3. Triterpenoids from Arctium lappa.

    Jeelani, S; Khuroo, M A


    Phytochemical investigation of the leaves of Arctium lappa led to the isolation of two triterpenoids, characterised by NMR, IR and MS as 3α-hydroxylanosta-5,15-diene and 3α-acetoxy-hop-22(29)-ene. 3α-hydroxylanosta-5,15-diene is a new triterpenoid and is isolated for the first time from this genus.

  4. Biotransformation of dianabol with the filamentous fungi and β-glucuronidase inhibitory activity of resulting metabolites.

    Khan, Naik T; Zafar, Salman; Noreen, Shagufta; Al Majid, Abdullah M; Al Othman, Zeid A; Al-Resayes, Saud Ibrahim; Atta-ur-Rahman; Choudhary, M Iqbal


    Biotransformation of the anabolic steroid dianabol (1) by suspended-cell cultures of the filamentous fungi Cunninghamella elegans and Macrophomina phaseolina was studied. Incubation of 1 with C. elegans yielded five hydroxylated metabolites 2-6, while M. phaseolina transformed compound 1 into polar metabolites 7-11. These metabolites were identified as 6β,17β-dihydroxy-17α-methylandrost-1,4-dien-3-one (2), 15α,17β-dihydroxy-17α-methylandrost-1,4-dien-3-one (3), 11α,17β-dihydroxy-17α-methylandrost-1,4-dien-3-one (4), 6β,12β,17β-trihydroxy-17α-methylandrost-1,4-dien-3-one (5), 6β,15α,17β-trihydroxy-17α-methylandrost-1,4-dien-3-one (6), 17β-hydroxy-17α-methylandrost-1,4-dien-3,6-dione (7), 7β,17β,-dihydroxy-17α-methylandrost-1,4-dien-3-one (8), 15β,17β-dihydroxy-17α-methylandrost-1,4-dien-3-one (9), 17β-hydroxy-17α-methylandrost-1,4-dien-3,11-dione (10), and 11β,17β-dihydroxy-17α-methylandrost-1,4-dien-3-one (11). Metabolite 3 was also transformed chemically into diketone 12 and oximes 13, and 14. Compounds 6 and 12-14 were identified as new derivatives of dianabol (1). The structures of all transformed products were deduced on the basis of spectral analyses. Compounds 1-14 were evaluated for β-glucuronidase enzyme inhibitory activity. Compounds 7, 13, and 14 showed a strong inhibition of β-glucuronidase enzyme, with IC50 values between 49.0 and 84.9 μM. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. [Chemical constituents of Poria cocos].

    Yang, Peng-Fei; Liu, Chao; Wang, Hong-Qing; Li, Jia-Chun; Wang, Zhen-Zhong; Xiao, Wei; Chen, Ruo-Yun


    The chemical constituents of Poria cocos were studied by means of silica gel, ODS column chromatography, Sephadex LH-20 and preparative HPLC. Thirteen compounds were isolated from this plant. By analysis of the ESI-MS and NMR data, the structures of these compounds were determined as tumulosic acid (1), dehydrotumulosic acid (2), 3beta, 5alpha-dihydroxy-ergosta-7, 22-dien-6-one (3), 3beta, 5alpha, 9alpha-trihydroxy-ergosta-7, 22-diene -6-one (4), ergosta-7, 22-diene-3-one (5), 6, 9-epoxy-ergosta-7,22-diene-3-ol (6), ergosta-4,22-diene-3-one (7), 3beta, 5alpha, 6beta-trihydroxyl-ergosta-7,22-diene (8), ergosta-5, 6-epoxy-7,22-dien-3-ol (9), beta-sitosterol (10), ribitol (11), mannitol (12), and oleanic acid 3-O-acetate (13), respectively. Compounds 3-13 were isolated from the P. cocos for the first time.

  6. Two New Sterols from Amoora yunnanensis


    Two new sterols, 3β,7α,16β-trihydroxy-stigmast-5,22-diene 1, 3β,7α,16β-trihydroxy-stigmast-5-ene 2, were isolated together with two known ergosterols, ergosta-5,24(28)-diene-3β,7α-diol, ergosta-5,24(28)-diene-3β,7α,16β-triol from the bark of Amoora yunnanensis (H. L. Li) C. Y. Wu. Their structures were deduced on the basis of spectral data.

  7. Close Air Support: Why All the Fuss


    column, and hamlet defense in Indochina and South Vietnam; and siege-breaking at Dien Bien Phu and Khe Sanh. In all of these cases, CAS substituted...the Dien Bien Phu experience, and, indeed, enabled Khe Sanh to accomplish what the French at Dien Blien Phu had tried and failed to achieve: create a...technological frontiers on which the Air Force has always sought leadership. It fits nicely their service " persona ." But, is it in the Army’s interest to take

  8. Analysis of Decisions Made Using the Analytic Hierarchy Process


    1.1 The Problem of Mirror Imaging In Dien Bien Phu, 1954, the colonial French army, attempting to cut the Vietminh supply lines into Laos, chose...outmatching the French in artillery numbers, leading to the French defeat at Dien Bien Phu. This was a historic defeat, since a small, poorly equipped and...ill-trained military was able to defeat a first world power. France’s failure at Dien Bien Phu was primarily a result of the cognitive trap of mirror

  9. Synthesis of (+)-discodermolide by catalytic stereoselective borylation reactions.

    Yu, Zhiyong; Ely, Robert J; Morken, James P


    The marine natural product (+)-discodermolide was first isolated in 1990 and, to this day, remains a compelling synthesis target. Not only does the compound possess fascinating biological activity, but it also presents an opportunity to test current methods for chemical synthesis and provides an inspiration for new reaction development. A new synthesis of discodermolide employs a previously undisclosed stereoselective catalytic diene hydroboration and also establishes a strategy for the alkylation of chiral enolates. Furthermore, this synthesis of discodermolide provides the first examples of the asymmetric 1,4-diboration of dienes and borylative diene-aldehyde couplings in complex-molecule synthesis.

  10. Synthesis of (+)-Discodermolide by Catalytic Stereoselective Borylation Reactions**

    Yu, Zhiyong; Ely, Robert J.


    The marine natural product (+)-discodermolide was first isolated in 1990 and, to this day, remains a compelling synthesis target. Not only does the compound possess fascinating biological activity, but it also presents an opportunity to test current methods for chemical synthesis and provides a forum for the inspiration of new reaction development. In this manuscript, we present a synthesis of discodermolide that employs a previously undisclosed stereoselective catalytic diene hydroboration and also establishes a strategy for chiral enolate alkylation. In addition, this synthesis of discodermolide provides the first examples of diene 1,4-diboration and borylative diene-aldehyde couplings in complex molecule synthesis. PMID:25045037

  11. Diels-alder cycloaddition of 2-azadienes to methyl 2-(2,6-dichlorophenyl)-2H-azirine-3-carboxylate in the synthesis of methyl 4-oxo-1,3-diazabicyclo[4.1.0]heptane-6-carboxylates

    Alves, M. José; Durães, M. Miguel; Fortes, A. Gil


    A number of fused 4-oxo-1,3-diazabicyclo[4.1.0]heptane-6-carboxylates, a new type of compound, have been obtained by Diels-Alder cycloaddition between nucleophilic 2-azadienes and an electrophilic 2H-azirine. The reactions are completely endo- and regioselective, the azirine being added by its less hindered face to the diene. There are two isomers 7 and 8 formed from dienes 1 due either to isomerization of the cycloadducts 7 and 8 or by isomerization of the C=N bond of the diene during the re...

  12. Cucurbitane-type triterpenoids from the fruit pulp of Momordica charantia.

    Liao, Yun-Wen; Chen, Chiy-Rong; Kuo, Yueh-Hsiung; Hsu, Jue-Liang; Shih, Wen-Ling; Cheng, Hsueh-Ling; Huang, Tzou-Chi; Chang, Chi-I


    Three new cucurbitane-type triterpenoids, 5beta,19-epoxy-23(R)-methoxycucurbita-6,24-dien-3beta-ol (1), 5beta,19-epoxy-23(S)-methoxycucurbita-6,24-dien-3beta-ol (2), and 3beta-hydroxy-23(R)-methoxycucurbita-6,24-dien-5beta,19-olide (3), were isolated from the fruit pulp of Momordica charantia. Their structures were established on the basis of extensive NMR (1H, 13C, COSY, HMQC, HMBC, and NOESY) and EI-MS studies. Compound 1 exhibited cytotoxic activity against the SK-Hep 1 cell line.

  13. Crystal structure of μ-carbonyl-1:2κ2 C:C-carbonyl-1κC-(1η5-cyclo­penta­dien­yl)iodido-2κI-[μ-2-(pyridin-2-yl)ethene-1,1-diyl-1κC 1:2κ2 N,C 1]ironpalladium(Fe—Pd) benzene monosolvate

    Verpekin, Victor V.; Kreindlin, Arkadii Z.; Semeikin, Oleg V.; Smol’yakov, Alexander F.; Dolgushin, Fedor M.; Chudin, Oleg S.; Ustynyuk, Nikolai A.


    The reaction of Cp(CO)2FeI with 2-ethynyl­pyridine under Sonogashira conditions [5% PdCl2(PPh3)2, 10% CuI, THF–NEt3 (2:1)] afforded the title binuclear μ-pyridyl­vinyl­idene FePd complex (FePd1) as a benzene solvate, [FePd(C5H5)(C7H5N)I(CO)2]·C6H6, in a very low yield rather than the expected iron o-pyridyl­ethynyl complex Cp(CO)2Fe—C≡C-(2-C5H4N). The Fe and Pd atoms in FePd1 are bridged by carbonyl and pyridyl­vinyl­idene ligands, the pyridyl N atom being bonded to the palladium atom. The use of equimolar amounts of PdCl2 increases the yield of FePd1 to 12%. The reaction pathway leading to FePd1 is proposed. PMID:28083139

  14. Cloning and Sequence Analysis of Lipoxygenase Gene cDNA from Cucumber Fruit (Cucumis sativus L.)

    Z.K. Wang; Z.W. Qin; X.Y. Zhou; D.Y. Song


    @@ Lipoxygenases are nonheme-iron-containing dioxygenases that catalyze the hydroperoxidation of unsatrated fatty acids containing a cis, cis-1,4-pentadiene structure producing hydroperoxy acids with conjugated dienes.

  15. Asymmetric synthesis of gem-diaryl substituted cyclic sulfamidates and sulfamides by rhodium-catalyzed arylation of cyclic ketimines.

    Nishimura, Takahiro; Ebe, Yusuke; Fujimoto, Hiroto; Hayashi, Tamio


    Asymmetric addition of arylboronates to aryl-substituted cyclic ketimines proceeded in the presence of a rhodium catalyst coordinated with a chiral diene ligand to give high yields of sulfamidates and sulfamides with high enantioselectivity (up to 99% ee).

  16. Tandem aldol condensation-Diels–Alder-aromatization sequence of reactions: a new pathway for the synthesis of 2-tetralone derivatives

    Mohammadi, Mohaddeseh; Harms, Klaus; Abaee, M. Saeed; Mojtahedi, Mohammad M; Doustkhah, Esmail


    .... In situ formed dienes reacted with diethyl acetylenedicarboxylate at room temperature and the process was followed by spontaneous aromatization of the cycloadducts to produce high yields of the final tetralone products...

  17. Diversity oriented approach to polycyclics via cross-enyne metathesis and Diels-Alder reaction as key steps

    Sambasivarao Kotha; Vittal Seema; Shaibal Banerjee; Mrityunjay Kumar Dipak


    Polycyclics containing biaryls have been prepared via application of cross-enyne metathesis and the Diels−Alder reaction. Here, ethylene and 1,5-hexadiene were used as a cross-metathesis partners to generate key diene intermediates.

  18. Oxidative stability of Liposomes composed of docosahexaenoic acid-containing phospholipids

    Vikbjerg, Anders Falk; Andresen, Thomas Lars; Jørgensen, Kent


    Oxidative stability of liposomes made of (Docosahexaenoic acid) DHA-containing phosphatidylcholine (PC) was examined during preparation and storage. After preparation of the liposomes, the concentration of primary (conjugated dienes) and secondary oxidation products (Thiobarbituric acid...

  19. V tshju dudu dudit Dudu? / Nikolai Karajev

    Karajev, Nikolai, 1978-


    ÜRO eriraportööri Doudou Diene inimõiguste komisjonile esitatud raportist Eesti kohta, kus ta avaldab rahulolu, et Eesti valitsus on näidanud poliitilist tahet rassismi ja diskrimineerimist puudutavate probleemide lahendamiseks

  20. Ozonolysis of unsaturated compounds in the synthesis of insect pheromones and juvenoids

    Ishmuratov, Gumer Yu; Kharisov, Rinat Ya; Odinokov, Viktor N.; Tolstikov, Genrikh A.


    The review surveys data on the use of the ozonolysis of cyclic and acyclic monoenes, dienes, and trienes in various stages of the total synthesis of insect pheromones and juvenoids. The bibliography includes 178 references.

  1. Zinc Mediated Tandem Fragmentation-Allylation of Methyl 5-Iodopentofuranosides

    Hyldtoft, Lene; Madsen, Robert


    In the presence of zinc and allyl bromide methyl 5-iodopentofuranosides undergo a tandem fragmentation alkylation to give functionalized dienes. These can undergo ring-closing olefin metathesis to produce cyclohexenes which on dihydroxylation give quercitols....

  2. Microstructural Investigation of Deformation and Failure Mechanisms in Polypropylene


    propylene random copolymer (EPR), maleated ethylene-propylene-diene monomer ( EPDM ), and maleated styrene-ethylene-butylene- styrene block copolymers... stability . Consequently, the arrangement of these crystalline phases (parallel or perpendicular to the applied stress) completely controls the fracture

  3. Preventing Rancidity in sunflower Oil

    used in turn to extract the polar flavonoids, while chilled acetone and petroleum ether ... sunflower oil was measured using changes in peroxide values and the UV absorbances (Conjugated diene) .... metal ions and metalloprotein catalysts.

  4. Kinetics and mechanism of the oxidation of alkenes and silanes by hydrogen peroxide catalyzed by methylrhenium trioxide (MTO) and a novel application of electrospray mass spectrometry to study the hydrolysis of MTO

    Tan, Haisong [Iowa State Univ., Ames, IA (United States)


    Conjugated dienes were oxidized by hydrogen peroxide with methylrhenium trioxide (MTO) as catalyst. Methylrhenium bis-peroxide was the major reactive catalyst present. Hydroxyalkenes and trisubstituted silane were also tested. Mechanisms for each of these reactions are presented.

  5. Four steroidal alkaloids from the leaves of Buxus sempervirens.

    Loru, F; Duval, D; Aumelas, A; Akeb, F; Guédon, D; Guedj, R


    Four new steroidal alkaloids, N20-formylbuxaminol E [(20S)-16alpha-hydroxy-20-(formylamino)-3beta-(dimethylamino)-9,10 -seco-buxa-9(11),10(19)-diene] (1), O16-syringylbuxaminol E [(20S)-16alpha-syringoyl-3beta-(dimethylamino)-20-(amino)-9, 10-seco-buxa-9(11),10(19)-diene] (2), N20-acetylbuxamine G [(20S)-20-(acetylamino)-3beta-(methylamino)-9,10-seco-buxa-9(11),1 0(19)-diene] (3) and N20-acetylbuxamine E [(20S)-20-(acetylamino)-3beta-(dimethylamino)-9,10-seco-buxa-9(11) ,10(19)-diene] (4) were isolated from the leaves of Buxus sempervirens. Their structures were determined mainly on the basis of 2D NMR studies.

  6. Fluorinated 5- and 7-membered carbacycle motifs by reaction of difluorocarbene with acetylene ethers.

    Chia, Poh Wai; Bello, Davide; Slawin, Alexandra M Z; O'Hagan, David


    The reaction of acetylene ethers with difluorocarbene (CF(2)), generated from the Ruppert-Prakash reagent, unexpectedly gave rise to co-produced fluorinated bicyclic [2.1.1]-hex-2-ene and cyclohepta-1,4-diene ring products.

  7. Isolation and Identification of Two New Polyhydroxylated Sterols from Soft Coral Sinularia sp.

    LIAO Xiao-jian; TANG Li-dan; LIANG Yuan-wei; GENG Hua-wei; XU Shi-hai


    Two new polyhydroxysteroids, 12β,16β,20-trihydroxycholesta-1,4-dien-3-one 16-acetate(1) and 24methyl-12β, 16β,20-trihydroxycholesta-1,4-dien-3-one(2) were isolated from octocoral Sinularia sp. Their structures were elucidated primarily on the basis of 1D and 2D NMR and the mass spectroscopic studies. The cytotoxicity of these compounds against three tumor cell lines was also reported.

  8. Zinc Mediated Tandem Fragmentation-Allylation of Methyl 5-Iodopentofuranosides

    Hyldtoft, Lene; Madsen, Robert


    In the presence of zinc and allyl bromide methyl 5-iodopentofuranosides undergo a tandem fragmentation alkylation to give functionalized dienes. These can undergo ring-closing olefin metathesis to produce cyclohexenes which on dihydroxylation give quercitols.......In the presence of zinc and allyl bromide methyl 5-iodopentofuranosides undergo a tandem fragmentation alkylation to give functionalized dienes. These can undergo ring-closing olefin metathesis to produce cyclohexenes which on dihydroxylation give quercitols....

  9. EFSA CEF Panel (EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids), 2015. Scientific Opinion on Flavouring Group Evaluation 213, Revision 2 (FGE.213Rev2): Consideration of genotoxic potential for α,β-unsaturated alicyclic ketones and precursors from chemical subgroup 2.7 of FGE.19

    Beltoft, Vibe Meister; Nørby, Karin Kristiane

    . Moreover, the Panel reconsidered the available data on p-mentha-1,4(8)-dien-3-one [FL-no: 07.127], based on new data on the structurally related substance pulegone, and concluded that additional genotoxicity data are needed to rule out the concern for genotoxicity of p-mentha-1,4(8)-dien-3-one [FL-no: 07.127]....

  10. Studies on chemical constituents of Fuscoporia obliqua%桦褐孔菌化学成分的研究

    何坚; 冯孝章


    Object A systematic study on the chemical constituents ofFuscoporia oblique Fr. Te. LáT was carried out. Methods The constituents were isolated on silica gel column chromatography, identified by physico-chemical properties and structurally elucidated by spectral analysis (MS, 1H,13CNMR and IR). Results 9 compounds were identified, namely fuscoporine (Ⅰ), lanosterol (Ⅱ), 3β-hydroxy-lanosta-8, 24-diene-21-al (Ⅲ), 3β, 21-dihydroxy-lanosta-8, 24-diene (Ⅳ), 3β-hydroxy-lanosta-8, 24-diene-21-acid (Ⅴ), 3β, 22R-dihydroxy-lanosta-8, 24-diene (Ⅵ), ergosterol peroxide (Ⅶ), analog of sphingin (Ⅷ) and mannitol(Ⅸ). Conclusion Compound I is a new pigment and named as fuscoporine.%目的 对桦褐孔菌Fuscoporia obliquaFr.Te.LáT的化学成分进行系统研究。方法 采用硅胶柱层析进行分离,通过理化常数测定和波谱(MS、1H,13CNMR、IR)技术进行结构鉴定。结果 分析鉴定了9个化合物,它们分别为:桦褐孔菌素(fuscoporine,Ⅰ)、lanosterol(Ⅱ)、3β-hydroxy-lanosta-8,24-diene-21-al(Ⅲ)、3β,21-dihydroxy-lanosta-8,24-diene(Ⅳ)、3β-hydroxy-lanosta-8,24-diene-21-acid(Ⅴ)、3β,22R-dihydroxy-lanosta-8,24-diene(Ⅵ)、ergosterolperoxide(Ⅶ)、analogofsphingin(Ⅷ)和mannitol(Ⅸ)。结论 化合物Ⅰ为一新化合物,命名为桦褐孔菌素。

  11. Analysis of Required Supporting Systems for the Supercritical CO(2) Power Conversion System


    Environmental Protection Agency EPDM Ethylene-Propylene Diene Monomer EPMA Electron Probe Micro-Analysis ETGBR Existing Technology Gas Breeder Reactor FID...second stabilization period before starting the CO2 transfer to see if the initial density would stabilize closer to the values provided by NIST...closed valve at all. Valve sizing methods can be found in Ouderkirk, 2002. Neoprene, nylon, ethylene-propylene diene monomer ( EPDM ), and

  12. Synthesis and Natural Distribution of Anti-inflammatory Alkamides from Echinacea

    Eve Wurtele


    Full Text Available The synthesis of the alkamides 2Z,4E-undeca-2,4-dien-8,10-diynoic acid isobutyl amide (1 and 2Z,4E-undeca-2,4-dien-8,10-diynoic acid isobutyl amide (5 was accomplished by organometallic coupling followed by introduction of the doubly unsaturated amide moiety. The distribution of these two amides in accessions of the nine species of Echinacea was determined.

  13. Two new triterpenoid saponins from Dianthus superbus L.

    Chen, Xia; Luo, Jian-Guang; Kong, Ling-Yi


    Two new triterpenoid saponins (1 and 2) were isolated from the dried aerial parts of Dianthus superbus L. (Caryophyllaceae). Their structures were elucidated on the basis of spectral data to be 3-O-beta-D-glucopyranosyl olean-9(11),12-diene-23,28-dioic acid 28-O-beta-D-glucopyranoside (1) and 3-O-beta-D-glucopyranosyl olean-11,13(18)-diene-23,28-dioic acid 28-O-beta-D-glucopyranoside (2).

  14. Structure elucidation of female-specific volatiles released by the parasitoid wasp Trichogramma turkestanica (Hymenoptera: Trichogrammatidae

    Armin Tröger


    Full Text Available Females of the parasitoid wasp Trichogramma turkestanica produce the putative polydeoxypropionates (2E,4E,6S,8S,10S-4,6,8,10-tetramethyltrideca-2,4-diene and (2E,4E,6S,8S,10S-4,6,8,10-tetramethyltrideca-2,4-dien-1-ol or their enantiomers as sex specific volatiles. The structures were assigned on the basis of GC–MS investigations using synthetic reference compounds.

  15. Constituents of south Indian vetiver oils.

    Mallavarapu, Gopal Rao; Syamasundar, Kodakandla V; Ramesh, S; Rao, Bhaskaruni R Rajeswara


    The essential oils isolated from vetiver [Vetiveria zizanioides (L.) Nash.] roots collected from four locations in south India were analyzed by GC-FID and GC-MS. Eighty constituents, representing 94.5-97.8% of the oils, have been identified. The oils from Bangalore, Hyderabad, Kundapur, and Mettupalayam were rich in sesquiterpenes and oxygenated sesquiterpenes with cedrane, bisabolane, eudesmane, eremophilane, and zizaane skeletons. The main components of the four essential oils were: eudesma-4,6-diene (delta-selinene) + beta-vetispirene (3.9-6.1%), beta-vetivenene (0.9-9.4%), 13-nor-trans-eudesma-4(15),7-dien-11-one + amorph-4-en-10-ol (5.0-6.4%), trans-eudesma-4(15),7-dien-12-ol (vetiselinenol) + (E)-opposita-4(15),7(11)-dien-12-ol (3.7-5.9%), eremophila-1 (10),11-dien-2alpha-ol (nootkatol) + ziza-6(13)-en-12-ol (khusimol) (16.1-19.2%), and eremophila-1(10),7(11)-dien-2alpha-ol (isonootkatol) + (E)-eremophila-1(10),7(11)-12-ol (isovalencenol) (5.6-6.9%). The important compounds that impart the characteristic vetiver odor are: khusimene, delta-selinene, beta-vetivenene, cyclocopacamphan-12-ol (epimers A and B), vetiselinenol, khusimol, isovalencenol, khusimone, alpha-vetivone, and beta-vetivone. The chemical profiles of the oils are comparable to Haitian vetiver oil.

  16. Identification and quantification of regioisomeric cholesteryl linoleate hydroperoxides in oxidized human low density lipoprotein and high density lipoprotein.

    Kenar, J A; Havrilla, C M; Porter, N A; Guyton, J R; Brown, S A; Klemp, K F; Selinger, E


    Oxidation of human LDL is implicated as an initiator of atherosclerosis. Isolated low density lipoprotein (LDL) and high density lipoprotein (HDL2) were exposed to aqueous radicals generated from the thermolabile azo compound 2,2'-azobis(2-amidinopropane) dihydrochloride. The primary nonpolar lipid products formed from the autoxidation of LDL and HDL were the regioisomeric cholesteryl linoleate hydroperoxides. In LDL oxidations, 9- and 13-hydroperoxides with trans,cis conjugated diene were formed as the major oxidation products if endogenous alpha-tocopheral was present in the LDL. After extended oxidation of LDL, at the time when endogenous alpha-tocopherol was consumed, the two trans,cis conjugated diene hydroperoxides began to disappear and the 9- and 13-hydroperoxides with trans,trans conjugated diene appeared. At very long oxidation times, none of the primary products, the conjugated diene hydroperoxides, were present. In HDL2, which has only very low levels of antioxidants, both the 9- and 13-hydroperoxides with trans,cis conjugated diene and the 9- and 13-hydroperoxides with trans,trans conjugated diene were formed at early stages of oxidation. The corresponding alcohols were also formed in the HDL2 oxidations. A mechanistic hypothesis consistent with these observations is presented.

  17. Prevention and recovery of (mu(3)-diethylentriamino)-chloro-palladium(II)-chloride induced inhibition of Na/K-ATPase by SH containing ligands--L-cysteine and glutathione.

    Krinulović, Katarina; Bugarcić, Zivadin; Vrvić, Miroslav; Krstić, Danijela; Vasić, Vesna


    The effect of (mu(3)-diethylentriamino)-chloro-palladium(II)-chloride ([PdCl(dien)]Cl) on the activity of Na/K-ATPase from porcine cerebral cortex was studied in vitro, in the absence and presence of -SH containing ligands L-cysteine and glutathione (GSH). The aim of the study was to elucidate the mechanism of [PdCl(dien)](+) induced inhibition of the enzyme activity and to examine the ability of thiols to prevent and recover the inhibition. The coordinative interaction between [PdCl(dien)](+) and enzyme was verified by UV and (1)H NMR spectra. The semblance in the changes in absorption spectra of [PdCl(dien)](+) in the presence of Na/K-ATPase and thiols (L-cysteine and GSH) suggested that the complex ion interacts with enzymatic sulfhydryl groups. [PdCl(dien)](+) inhibited the enzyme activity in a dose-dependent manner. The Hill analysis of the inhibition curve yielded the half-maximum inhibitory activity value, IC(50)=1.21 x 10(-4)M, and Hill coefficient, n=0.7, suggesting the negative cooperation for binding of [PdCl(dien)](+) to the enzyme. Dependence of the initial reaction rate on the concentration of MgATP(2-) exhibited typical Michelis-Menten kinetics in the absence and presence of the inhibitor. Kinetic analysis showed that [PdCl(dien)](+) inhibited Na/K-ATPase by reducing the maximum reaction rate (V(max)), rather than changing the affinity to the substrate (K(m)). Kinetic parameters derived using Lineweaver-Burk transformation of experimental data indicated the non-competitive nature of Na/K-ATPase inhibition. The inhibitory constant, K(i)=1.05 x 10(-4)M, was determined from secondary replot of Lineweaver-Burk graph, and correlated with stability constants of [Pd(dien)(thiol)] complexes. 1 x 10(-3)M L-cysteine or GSH prevented the enzyme inhibition induced by Pd(II) complex cation when present below 1 x 10(-4)M. The both thiols completely reversed the inhibited activity in the concentration dependent manner, due to the complex formation with [PdCl(dien)](+).

  18. Chemical constituents from the stem of Brosimum potabile (Moraceae Constituintes químicos do cerne de Brosimum potabile (Moraceae

    Viviane Gomes da Costa Abreu


    Full Text Available Three coumarins, 5-methoxypsoralene, xanthyletin, and (--marmesin, have been isolated from the ethanolic extract of the stem of the Amazonian plant Brosimum potabile. The structures were determined on the basis of NMR analyses and by comparison with spectroscopic data in the literature. The analysis of the hexane fractions by GC-MS in EIMS mode suggested the presence of (1-methylpentyl-benzene; α,α-dimethyl-4-(1-methylethyl-benzenemethanol; 1-methyl-3,5-bis(1-methylethyl-benzene; urs-12-ene; chola-5,22-dien-3β-ol; cholesta-4,6-dien-3β-ol; sitosteryl 9(Z-octadecenoate; cholesta-5,22-dien-3β-ol; cholesta-4,6,22-trien-3-one; and cholesta-4,22-dien-3-one. NMR data of other hexane fractions indicated the presence of 3β-acetoxy-lup-12,20(29-diene; 3β-acetoxy-olean-12-ene; 3β-acetoxy-urs-12-ene; and adian-5-ene. All these compounds are first described in B. potabile.Três cumarinas, 5-metoxipsoraleno, xantiletina e (--marmesina, foram isoladas no extrato etanólico do cerne da planta amazônica Brosimum potabile. Suas estruturas foram determinadas a partir das análises por RMN e por comparação com dados espectroscópicos da literatura. As análises das frações hexânicas por CG/EM sugeriram a presença de (1-metilpentil-benzeno; α,α-dimetil-4-(1-metiletil-benzenometanol; 1-metil-3,5-bis(1-metiletil-benzeno; urs-12-eno; cola-5,22-dien-3β-ol; colesta-4,6-dien-3β-ol; (9Z-octadecenoato de sitosterila; colesta-5,22-dien-3β-ol; colesta-4,6,22-trien-3-ona e colesta-4,22-dien-3-ona. Dados de RMN de outras frações hexânicas indicaram a presença de 3β-acetóxi-lup-12,20(29-dieno; 3β-acetóxi-olean-12-eno; 3β-acetóxi-urs-12-eno e adian-5-eno. Todos esses compostos foram identificados pela primeira vez em B. potabile.

  19. Steroidal saponins from the aerial parts of Dracaena draco and their cytostatic activity on HL-60 cells.

    Mimaki, Y; Kuroda, M; Ide, A; Kameyama, A; Yokosuka, A; Sashida, Y


    Chemical examination of the aerial parts of Dracaena draco has led to the isolation of a total of nine steroidal saponins, including five new ones. The structures of the new saponins were determined by spectral data and a few chemical transformations to be (23S,24S)-spirosta-5,25(27)-diene-1 beta,3 beta,23,24-tetrol 1-O-{O-(2,3,4-tri-O-acetyl-alpha-L-rhamnopyranosyl)-(1-->2)-alpha-L -arabinopyranosyl} 24-O-beta-D-fucopyranoside, (23S,24S)-spirosta-5,25(27)-diene-1 beta,3 beta, 23,24-tetrol 1-O-{O-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L -arabinopyranoside}, (23S,24S)-spirosta-5,25(27)-diene-1 beta,3 beta,23,24-tetrol 1-O-{O-(4-O- acetyl-alpha-L-rhamnopyranosyl)-(1-->2)-alpha-L-arabinopyransoide} , (23S)-spirosta-5,25(27)-diene-1 beta,3 beta,23-triol 1-O-{O-alpha-L- rhamnopyranosyl)-(1-->2)-alpha-L-arabinopyranoside} and (23S,24S)-spirosta-5,25(27)-diene-1 beta,3 beta,23-triol 1-O-{O-(4-O-acetyl-alpha-L-rhamnopyranosyl)-(1-->2)-alpha-L- arabinopyranoside}. The isolated saponins were evaluated for their cytostatic activity on leukemia HL-60 cells.

  20. Three New Clerodane Diterpenes from Polyalthia longifolia var. pendula

    Tung-Ho Wu


    Full Text Available Three new clerodane diterpenes, (4→2-abeo-cleroda-2,13E-dien-2,14-dioic acid (1, (4→2-abeo-2,13-diformyl-cleroda-2,13E-dien-14-oic acid (2, and 16(R&S- methoxycleroda-4(18,13-dien-15,16-olide (3, were isolated from the unripe fruit of Polyalthia longifolia var. pendula (Annonaceae together with five known compounds (4–8. The structures of all isolates were determined by spectroscopic analysis. The anti-inflammatory activity of the isolates was evaluated by testing their inhibitory effect on NO production in LPS-stimulated RAW 264.7 macrophages. Among the isolated compounds, 16-hydroxycleroda-3,13-dien-15,16-olide (6 and 16-oxocleroda-3,13-dien-15-oic acid (7 showed promising NO inhibitory activity at 10 µg/mL, with 81.1% and 86.3%, inhibition, respectively.

  1. New α-Glucosidase Inhibitory Triterpenic Acid from Marine Macro Green Alga Codium dwarkense Boergs

    Liaqat Ali


    Full Text Available The marine ecosystem has been a key resource for secondary metabolites with promising biological roles. In the current study, bioassay-guided phytochemical investigations were carried out to assess the presence of enzyme inhibitory chemical constituents from the methanolic extract of marine green alga—Codium dwarkense. The bioactive fractions were further subjected to chromatographic separations, which resulted in the isolation of a new triterpenic acid; dwarkenoic acid (1 and the known sterols; androst-5-en-3β-ol (2, stigmasta-5,25-dien-3β,7α-diol (3, ergosta-5,25-dien-3β-ol (4, 7-hydroxystigmasta-4,25-dien-3-one-7-O-β-d-fucopyranoside (5, 7-hydroxystigmasta-4,25-dien-3-one (6, and stigmasta-5,25-dien-3β-ol (7. The structure elucidation of the new compound was carried out by combined mass spectrometry and 1D (1H and 13C and 2D (HSQC, HMBC, COSY, and NOESY NMR spectroscopic data. The sub-fractions and pure constituents were assayed for enzymatic inhibition of alpha-glucosidase. Compound 1 showed significant inhibition at all concentrations. Compounds 2, 3, 5, and 7 exhibited a dose-dependent response, whereas compounds 4–6 showed moderate inhibition. Utilizing such marine-derived biological resources could lead to drug discoveries related to anti-diabetics.

  2. Otimização de propriedades mecânicas de misturas ternárias de polipropileno (PP/borracha de etileno-propileno-dieno (EPDM/pó de pneus (SRT sob tração e impacto usando a metodologia da superfície de resposta (MSR Optimization of mechanical properties of polypropylene (PP/ethylene-propylene-diene monomer rubber (EPDM/scrap rubber tire (SRT ternary mixtures under tensile and impact using the response surface methodology (RSM

    Helson M. da Costa


    Full Text Available A metodologia da superfície de resposta (MSR é uma coleção de técnicas estatísticas e matemáticas para desenvolver, melhorar e otimizar processos. Neste estudo, a técnica MSR foi aplicada na investigação do comportamento mecânico de diferentes misturas ternárias de PP/EPDM/SRT. Após a mistura apropriada em uma extrusora de dupla rosca co-rotante e a moldagem por injeção, as propriedades mecânicas (resistência à tração e a resistência ao impacto foram determinadas e usadas como variáveis de resposta. A microscopia eletrônica de varredura (MEV foi usada para investigar a morfologia das diferentes misturas e interpretar os resultados. Com ferramentas estatísticas específicas, um número mínimo de experimentos permitiu o desenvolvimento de um modelo de superfície de resposta e a otimização das concentrações dos componentes de acordo com o desempenho mecânico. Valores elevados de resistência ao impacto são alcançados (>80 J.m-1 quando, de acordo com as condições experimentais estudadas, a mistura física de PP/EPDM/SRT mantém as proporções de EPDM e SRT em torno de 25%.The response surface methodology (RSM is a collection of statistical and mathematical techniques for developing, improving and optimizing processes. In this study, RSM technique was applied to the investigation of the mechanical behavior of different PP/EPDM/SRT ternary mixtures. After appropriate processing in a co-rotating twin extruder and injection molding, the mechanical properties, such as tensile strength and impact strength, were determined and used as response variables. Scanning electron microscopy (SEM was used for investigating the morphology of the different blends and to interpret the results. With specific statistical tools, a minimum number of experiments allowed the response surface model to be developed and the concentrations of the components to be optimized according to the mechanical performance. High values of impact strength were reached (>80 J.m-1 when the PP/EPDM/SRT mixture had a EPDM/SRT ratio of around 25%.

  3. In Vitro Antileishmanial Activity of Sterols from Trametes versicolor (Bres. Rivarden).

    Leliebre-Lara, Vivian; Monzote Fidalgo, Lianet; Pferschy-Wenzig, Eva-Maria; Kunert, Olaf; Nogueiras Lima, Clara; Bauer, Rudolf


    Two ergostanes, 5α,8α-epidioxy-22E-ergosta-6,22-dien-3β-ol (1) and 5α-ergost-7,22-dien-3β-ol (2), and a lanostane, 3β-hydroxylanostan-8,24-diene-21-oic acid (trametenolic acid) (3), were isolated from an n-hexane extract prepared from the fruiting body of Trametes versicolor (Bres. Rivarden). The activity of the isolated sterols was evaluated against promastigotes and amastigotes of Leishmania amazonensis Lainson and Shaw, 1972. The lanostane, compound (3), showed the best inhibitory response (IC50 promastigotes 2.9 ± 0.1 μM and IC50 amastigotes 1.6 ± 0.1 μM). This effect was 25-fold higher compared with its cytotoxic effect on peritoneal macrophages from BALB/c mice. Therefore, trametenolic acid could be regarded as a promising lead for the synthesis of compounds with antileishmanial activity.

  4. The sterols of Cucurbita moschata ("calabacita") seed oil.

    Rodriguez, J B; Gros, E G; Bertoni, M H; Cattaneo, P


    From the sterol fraction of seed oil from commercial Cucurbita moschata Dutch ("calabacita") delta 5 and delta 7 sterols having saturated and unsaturated side chain were isolated by chromatographic procedures and characterized by spectroscopic (1H and 13C-nuclear magnetic resonance, mass spectrometry) methods. The main components were identified as 24S-ethyl 5 alpha-cholesta-7,22E-dien-3 beta-ol (alpha-spinasterol); 24S-ethyl 5 alpha-cholesta-7,22E,25-trien-3 beta-ol (25-dehydrochondrillasterol); 24S-ethyl 5 alpha-cholesta-7,25-dien-3 beta-ol; 24R-ethyl-cholesta-7-en-3 beta-ol (delta 7-stigmastenol) and 24-ethyl-cholesta-7, 24(28)-dien-3 beta-ol (delta 7,24(28)-stigmastadienol).

  5. A New Cytotoxic Sterol Produced By an Endophytic Fungus from Castaniopsis Fissa at the Couth China Sea Coast

    Hou Jin LI; Yong Cheng LIN; L. L. P. VRIJMOED; E. B. G. JONES


    A new sterol,ergosta-8(9),22-diene-3,5,6,7-tetraol(3β,5α,6β,7α,22E)(A)together with three known sterols:3β,5α,6β-trihydroxyergosta-7,22-diene(B),3β-hydroxy-5α,8α-epidioxyer-gosta-6,22-diene(C)and ergosterol(D)were isolated from the mycelia of an unidentified endophytic fungus separated from Castaniopsis fissa(chestnut tree).Compound A exhibited potent selective cytotoxicity against Bel-7402,NCI4460 and L-02 cell lines with IC50values 8.445,5.03,13.621μg/mL,respectively.

  6. [Studies on the constituents of Scutellaria species. XV. On the diterpenoid constituents of the leaves of Scutellaria alpina L].

    Miyaichi, Y; Kizu, H; Yamaguchi, Y; Tomimori, T


    From the leaves of Scutellaria alpina L., four new neo-clerodane diterpenes (1-4) were isolated. The structures of 1-4 were shown to be (4S)-19-acetoxy-8 beta-hydroxy-6 alpha-benzoyloxy-4,18-epoxy-neo-cleroda-11,13- dien-15,16-olide, (4S)-19-acetoxy-8 beta-hydroxy-6 alpha-tigloyloxy-4,18-epoxy-neo-cleroda-11,13- dien-15,16-olide, (4S, 11S)-11-acetoxy-8 beta,19-dihydroxy-6 alpha-tigloyloxy-4,18-epoxy-neo- clerod-13-en-15,16-olide, and (4S)-19-acetoxy-8 beta-hydroxy-6 alpha, 7 beta-dibenzoyloxy-4,18-epoxy-neo- cleroda-11,13-dien-15,16-olide, respectively, by the chemical and spectral data.

  7. Four new eremophilendiolides from Ligularia atroviolacea

    Shu Yun Shi; Yu Zhao; Di Yao Wu; Xun Gong; Hua Peng; Rong Ping Zhang; Chang Xin Zhou; Xiao Jiang Hao; Zhong Jian Jia; Joachim St(o)ckigt


    From Ligularia atroviolacea, four new eremophilendiolides, 8β-hydroxy-eremophil-3,7 (1 1)-dien-12,8α(14,6α)-diolide (1),8β-methoxy-eremophil-3,7(11)-dien-12,8α(14,6α)-diolide (2), 8α-hydroxy-eremophil-3,7(11)-dien-12,8β(14,6α)-diolide (3) and eremophil-3,7(11),8-trien-12,8 (14,6α)-diolide (4), as well as a known diolide (5) were isolated. Their structures were elucidated on the basis of 1D and 2D NMR as well as ESI-MS spectral data.


    Olivia Márquez-Fernández


    Full Text Available C inco compuestos de una cepa comercial del hongo Pleurotus sp. se obtuvieron a partir de extracciones con acetato de etilo y metanol. Los compuestos se aislaron por medio de técnicas como la cromatografía en columna y en capa fina. Los siguientes esteroles fue - ron identificados mediante espectroscopía RMN 1 H: 1 ergosta-5, 7, 22-trien-3β-ol (er - gosterol, 2 5α, 8α-epidioxi-22E-ergosta-6, 22-dien-3β-ol (peróxido de ergosterol, 3 3β, 5α, 6β, 9α-tetrahidroxiergosta-7, 22-dieno, 4 3 β , 5 α , 6 β , 9 α -tetrahydroxyergosta-7, 22-dien y 5 3β, 5α, 9α-trihidroxiergosta-7, 22-dien-6-ona.

  9. Sequential Diels–Alder/[3,3]-sigmatropic rearrangement reactions of β-nitrostyrene with 3-methyl-1,3-pentadiene

    Peter A. Wade


    Full Text Available The tin(IV-catalyzed reaction of β-nitrostyrene with (E-3-methyl-1,3-pentadiene in toluene afforded two major nitronic ester cycloadducts in 27% and 29% yield that arise from the reaction at the less substituted diene double bond. Also present were four cycloadducts from the reaction at the higher substituted diene double bond, two of which were the formal cycloadducts of (Z-3-methyl-1,3-pentadiene. A Friedel–Crafts alkylation product from the reaction of the diene, β-nitrostyrene, and toluene was also obtained in 10% yield. The tin(IV-catalyzed reaction of β-nitrostyrene with (Z-3-methyl-1,3-pentadiene in dichloromethane afforded four nitronic ester cycloadducts all derived from the reaction at the higher substituted double bond. One cycloadduct was isolated in 45% yield and two others are formal adducts of the E-isomer of the diene. The product formation in these reactions is consistent with a stepwise mechanism involving a zwitterionic intermediate. The initially isolated nitronic ester cycloadducts underwent tin(IV-catalyzed interconversion, presumably via zwitterion intermediates. Cycloadducts derived from the reaction at the less substituted double bond of (E-3-methyl-1,3-pentadiene underwent a [3,3]-sigmatropic rearrangement on heating to afford 4-nitrocyclohexenes. Cycloadducts derived from the reaction at the higher substituted diene double bond of either diene failed to undergo a thermal rearrangement. Rates and success of the rearrangement are consistent with a concerted mechanism possessing a dipolar transition state. An initial assessment of substituent effects on the rearrangement process is presented.

  10. Analysis of the chemical composition of essential oil from Algerian Inula viscosa (L. Aiton

    Imad Eddine Haoui


    Full Text Available The chemical composition of the essential oil of Inula viscosa (L. leaves, obtained by both hydrodistillation and steam distillation, was investigated by GC–MS. The major components for hydrodistillation were: 12-carboxyeudesma-3,11 (13 diene (28.88%; linolenic acid (7.80%; palmitic acid (5.38%; butyl hydroxy toluene (4.11% and fokienol (3.37%, while for steam distillation were: 12-carboxyeudesma-3,11 (13 diene (56.81%; 2,3-didehydrocostic acid (3.25%; butyl hydroxy toluene (2.63% and pentacosane (2.31%.

  11. Enhancement of Adhesion between EPDM and Polyester Fabric by Using Natural Rubber Modified by Maleic Anhydride

    A. A. El-Wakil


    Full Text Available This study presents a new method for improving adhesion between ethylene propylene diene monomer (EPDM rubber and polyester fabric. In this work, natural rubber was modified by maleic anhydride in order to improve the adhesion force between ethylene propylene diene monomer rubber and polyester fabric. The effect of thermal aging and ionizing radiation on the stability of the rubber mix as well as on the peel strength of the rubber-coated fabric was investigated. It was observed that the natural rubber modified by maleic anhydride improved the peel strength of the EPDM rubber-coated polyester fabric.

  12. Synthetic Strategies for Converting Carbohydrates into Carbocycles by the Use of Olefin Metathesis

    Madsen, Robert


    , protecting groups and substituents. Subsequent ring-closing metathesis with a ruthenium carbene complex affords highly functionalized carbocycles with ring-sizes ranging from five- to eight-membered rings. The application of these methods for the synthesis of carbocyclic natural products from carbohydrates......This microreview covers recent advances in the use of ring-closing metathesis for the synthesis of carbocycles from carbohydrates. Various strategies for the synthesis of a,w-dienes from carbohydrates are presented, which give rise to a large variety of dienes with different stereochemistry...

  13. Cucurbitane-type triterpenes from Citrullus lanatus (watermelon) seeds.

    Kikuchi, Takashi; Okada, Rina; Harada, Yu; Ikushima, Kenji; Yamakawa, Takahiro; Yamada, Takeshi; Tanaka, Reiko


    Two new cucurbitane-type triterpenes, 24-hydroperoxycucurbita-5,25-dien-3beta-ol (1) and 25-hydroperoxycucurbita-5,23-dien-3beta-ol (2), were isolated from a MeOH extract of Citrullus lanatus seeds. Compounds 1 and 2 exhibited moderate cytotoxic activities with IC50 values of 33.4-52.4 microM against HL-60 (human leukemia), P388 (murine leukemia), and L1210 (murine leukemia) cells. Compound 1 showed melanogenesis inhibitory activity (melanin content 80.0 %) with low cytotoxicity (cell viability 97.6%) at a low concentration (10 microM).

  14. Parameters: US Army War College Quarterly. Volume 20. Number 4


    South Vietnam; and siege-breaking at Dien Bien Phu and Khe Sanh. In all of these cases, CAS substituted for a lack of available artillery assets, and...service persona . But is it in the Army’s interest to take over CAS, much less all of tactical aviation? No. The Army cannot afford the force structure...of a Former Iron Curtain Official." 10 (September, 1980), 8-15. Radvanyi, Janos. "Dien Bien Phu: Tiirt ’ears After." 15 (Summer, 1985), 63-68. Raho

  15. Two New Antioxidant Triterpenoids from Lonicera quinquelocularis

    Dilfaraz Khan


    Full Text Available Two new tri terpenoids namely, 3α - hydroxyferna-7, 9(11,22-trien-12-one (1 and 3α - acetoxyferna-7, 9(11-dien-22-ol (2 along with two known compounds 3α,16α-dihydroxyferna-7,9(11-dien-12-one (3 and 3α,16α-dihydroxyfern a -8-en-11-one (4 were isolated from Lonicera quinquelocularis . Their structures were elucidated by chemical and modern spectroscopic techniques. All the compounds showed good antioxidant activities in the DPPH radical scavenging assay.

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

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


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

  17. Enantio- and Periselective Nitroalkene Diels-Alder Reactions Catalyzed by Helical-Chiral Hydrogen Bond Donor Catalysts

    Zhili Peng


    Full Text Available Helical-chiral double hydrogen bond donor catalysts promote the nitroalkene Diels-Alder reaction in an enantio- and periselective manner. This represents the first asymmetric catalytic nitroalkene Diels-Alder reaction via LUMO-lowering catalysis. To gain an insight into this new process, the substrate scope of our catalyst was investigated by exploiting readily available 5-substituted pentamethylcyclopentadienes. The catalyst was found to tolerate dienes with different steric demands as well as dienes substituted with heteroatoms. The synthetic utility of 5-substituted pentamethylcyclopentadienes is rather limited, and thus we have developed a three-step route to 1,4,5,5-tetrasubstituted cyclopentadienes from commercially available ketones.

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

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


    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.

  19. Reversible Thermoset Adhesives

    Mac Murray, Benjamin C. (Inventor); Tong, Tat H. (Inventor); Hreha, Richard D. (Inventor)


    Embodiments of a reversible thermoset adhesive formed by incorporating thermally-reversible cross-linking units and a method for making the reversible thermoset adhesive are provided. One approach to formulating reversible thermoset adhesives includes incorporating dienes, such as furans, and dienophiles, such as maleimides, into a polymer network as reversible covalent cross-links using Diels Alder cross-link formation between the diene and dienophile. The chemical components may be selected based on their compatibility with adhesive chemistry as well as their ability to undergo controlled, reversible cross-linking chemistry.

  20. Enantio- and periselective nitroalkene Diels-Alder reactions catalyzed by helical-chiral hydrogen bond donor catalysts.

    Peng, Zhili; Narcis, Maurice J; Takenaka, Norito


    Helical-chiral double hydrogen bond donor catalysts promote the nitroalkene Diels-Alder reaction in an enantio- and periselective manner. This represents the first asymmetric catalytic nitroalkene Diels-Alder reaction via LUMO-lowering catalysis. To gain an insight into this new process, the substrate scope of our catalyst was investigated by exploiting readily available 5-substituted pentamethylcyclopentadienes. The catalyst was found to tolerate dienes with different steric demands as well as dienes substituted with heteroatoms. The synthetic utility of 5-substituted pentamethylcyclopentadienes is rather limited, and thus we have developed a three-step route to 1,4,5,5-tetrasubstituted cyclopentadienes from commercially available ketones.

  1. A new glucoceramide from the watermelon Begonia, Pellionia repens.

    Luo, Yinggang; Liu, Yan; Qi, Huayi; Zhang, Guolin


    A new glucoceramide named pellioniareside (1) was isolated from the aqueous ethanolic extract of whole plants of Pellionia repens, together with lupeol (2), uracil (3), (22E,20S,24R)-5alpha,8alpha-epidioxyergosta-6,22-dien-3-beta-ol (4), and daucosterol (5). The structure and relative configurations of pellioniareside were identified as (2S,3S,4R,6E,8E)-1-O-beta-D-glucopyranosyl-2-[(2 R)-2-hydroxytetracosanoylamino]-1,3,4-octadecanetriol-6,8-diene by analysis of spectral data and by chemical evidence.

  2. Alienusolin, a new 4α-deoxyphorbol ester derivative, and crotonimide C, a new glutarimide alkaloid from the Kenyan Croton alienus.

    Ndunda, Beth; Langat, Moses K; Wanjohi, John M; Midiwo, Jacob O; Kerubo, Leonidah O


    Two novel compounds, alienusolin, a 4α-deoxyphorbol ester (1), crotonimide C, a glutarimide alkaloid derivative (2), and ten known compounds, julocrotine (3), crotepoxide (4), monodeacetyl crotepoxide (5), dideacetylcrotepoxide, (6), β-senepoxide (7), α-senepoxide (8), (+)-(2S,3R-diacetoxy-1-benzoyloxymethylenecyclohex-4,6-diene (9), benzyl benzoate (10), acetyl aleuritolic (11), and 24-ethylcholesta-4,22-dien-3-one (12) were isolated from the Kenyan Croton alienus. The structures of the compounds were determined using NMR, GCMS, and HRESIMS studies.

  3. Sterols from the Fungus Catathelasma imperiale

    YANG, Sheng-Ping; XU, Jun; YUE, Jian-Min


    Eight ergostane-type sterols and three their derivatives (one mono-linoleate and two mono-glucosides) were isolated from the ethyl acetate soluble fraction of the fungus Catathelasma imperiale. Two of them are novel compounds, namely 22E, 24R-ergosta-7,22-diene-3β, 5α-diol-6β-linoleate (1) and 22E, 24R-ergosta-7,22-diene-3β,5β,6α-triol (5) with an uncommon cisfused A/B ring. Structures of these compounds were demonstrated on the basis of their chemical evidences and spectroscopic methods, especially 2D NMR techniques.

  4. Microbial transformations of isocupressic acid.

    Lin, S J; Rosazza, J P


    Microbial transformations of the labdane-diterpene isocupressic acid (1) with different microorganisms yielded several oxygenated metabolites that were isolated and characterized by MS and NMR spectroscopic analyses. Nocardia aurantia (ATCC 12674) catalyzed the cleavage of the 13,14-double bond to yield a new nor-labdane metabolite, 2. Cunninghamella elegans (-) (NRRL 1393) gave 7beta-hydroxyisocupressic acid (3) and labda-7,13(E)-diene-6beta,15, 17-triol-19-oic acid (4), and Mucor mucedo (ATCC 20094) gave 2alpha-hydroxyisocupressic acid (5) and labda-8(17),14-diene-2alpha, 13-diol-19-oic acid (6).

  5. Cycloaddition of methyl 2-(2,6-dichorophenyl)-2H-azirine-3-carboxylate to electron rich 2-azadienes

    Alves, M. José; Durães, M. Miguel; Fortes, A. Gil


    Tert-Butyldimethylsililoxy-2-aza-1,3-butadienes react with 2H-azirine 3 leading to Diels-Alder cycloadducts in moderate yields. The reactions are endo- and regio- selective with the azirine being added by its less hindered face. There is only one product in the case of 1b, 4b. There are two isomers (4 and 5) from 1a, 1c and 1d. A different result was obtained with the diene 1e. Diene 1e formed products 4e and 8. Some of compounds 4 and 5 have been hydrolysed leading to functionalized aziridin...

  6. Antiprotozoal compounds from Asparagus africanus

    Oketch-Rabah, H A; Dossaji, S F; Christensen, S B


    Two antiprotozoal compounds have been isolated from the roots of Asparagus africanus Lam. (Liliaceae), a new sapogenin, 2 beta, 12 alpha-dihydroxy-(25R)-spirosta-4,7-dien-3-one (1), which was named muzanzagenin, and the lignan (+)-nyasol (2), (Z)-(+)-4,4'-(3-ethenyl-1-propene-1,3-diyl)-bisphenol.......Two antiprotozoal compounds have been isolated from the roots of Asparagus africanus Lam. (Liliaceae), a new sapogenin, 2 beta, 12 alpha-dihydroxy-(25R)-spirosta-4,7-dien-3-one (1), which was named muzanzagenin, and the lignan (+)-nyasol (2), (Z)-(+)-4,4'-(3-ethenyl-1-propene-1,3-diyl...

  7. Niobium Pentachloride Activation of Enone Derivatives: Diels-Alder and Conjugate Addition Products

    Gil Valdo José da Silva


    Full Text Available Niobium pentachloride has proven to be a powerful activating agent for Diels-Alder or conjugate addition reactions of cycloenones. The Diels-Alder product was obtained only with an unsubstituted enone (cyclohexenone and the highly reactive diene cyclopentadiene; substituents in the b-position of enones seem to prevent Diels-Alder reaction: oxygenated substituents favor the formation of vinyl chlorides (ethyl ether or dichloromethane as solvents or enol ethers (ethyl acetate as solvent, while a methyl substituent prevents any kind of transformation with NbCl5. Less reactive dienes, furan and 2-methylfuran gave the conjugate addition products of the furan ring to the enone system.

  8. Explaining the Bay of Pigs and Vietnam, 1965 Decisions


    time of the battle of Dien Bien Phu, Eisenhower referred to the situation in the often to be repeated "falling dminoes" vein. Indeed, Ho Chi Minh’s...though when he states: We do not pull apart thebe models for the sake of independent application. We have no notion that the casual factors

  9. An immunosuppressive tryptophan-derived alkaloid from Lepidagathis cristata.

    Ravikanth, V; Niranjan Reddy, V L; Ramesh, P; Prabhakar Rao, T; Diwan, P V; Khar, A; Venkateswarlu, Y


    An immunosuppressive, tryptophan-derived alkaloid cristatin A (1), and two known compounds, cycloartenol and stigmasta-5,11(12)-diene-3 beta-ol, were isolated from the whole plant Lepidagathis cristata Willd. The structures of the isolates were established by interpretation of their spectral data.

  10. Organic-Inorganic Hybrid Silica Material Derived from a Monosilylated Grubbs-Hoveyda Ruthenium Carbene as a Recyclable Metathesis Catalyst

    Michel Wong Chi Man


    Full Text Available The synthesis of a monosilylated Grubbs-Hoveyda ruthenium alkylidene complex is described, as well as the preparation and characterization of the corresponding material by sol-gel cogelification with tetraethoxysilane (TEOS and the assay of this recyclable supported catalyst in ring-closing diene and enyne metathesis reactions under thermal and microwave conditions.

  11. EPDM Rubber Reclaim from Devulcanized EPDM

    Sutanto, P.; Picchioni, F.; Janssen, L.P.B.M.; Dijkhuis, K.A.J.; Dierkes, Wilma K.; Noordermeer, Jacobus W.M.


    Two types of ethylene-propylene-diene monomer (EPDM) rubbers, namely an efficient vulcanized (EV) and a semiefficient vulcanized (SEV), have been used to produce devulcanizates in a continuous setup. The devulcanizates are re-cured using the same recipes as for the virgin rubber. The influence of

  12. EPDM rubber reclaim from devulcanized EPDM

    Sutanto, P.; Picchioni, F.; Janssen, L. P. B. M.; Dijkhuis, K. A. J.; Dierkes, W. K.; Noordermeer, J. W. M.


    Two types of ethylene-propylene-diene monomer (EPDM) rubbers, namely an efficient vulcanized (EV) and a serniefficient vulcanized (SEV), have been used to produce devulcanizates in a continuous setup. The devulcanizates are re-cured using the same recipes as for the virgin rubber. The influence of

  13. Impact behaviour of nylon-rubber blends: 5. Influence of the mechanical properties of the elastomer

    Borggreve, R.J.M.; Gaymans, R.J.; Schuijer, J.


    Blends of 90wt% nylon-6 and 10wt% impact modifier were prepared. As impact modifiers were used: EPDM (ethylene propylene diene monomer) rubber, EPM (ethylene propylene monomer) rubber, polyethylene, four poly(ether esters) and some commercial impact modifers. EPDM, EPM and polyethylene were function

  14. Conifer fibers as reinforcing materials for polypropylene-based composites

    Plackett, David; Chengzhi, Chuai; Almdal, Kristoffer


    Conifer fibers were used to reinforce polypropylene (PP). To improve the compatibility between the conifer fibers and the PP matrix, the fibers were either grafted with maleated PP (MAPP), treated by adding MAPP, or mixed with ethylene/propylene/diene terpolymer (EPDM). The treatments resulted in...

  15. Cobalt-Catalyzed [2π + 2π] Cycloadditions of Alkenes: Scope, Mechanism, and Elucidation of Electronic Structure of Catalytic Intermediates.

    Schmidt, Valerie A; Hoyt, Jordan M; Margulieux, Grant W; Chirik, Paul J


    Aryl-substituted bis(imino)pyridine cobalt dinitrogen compounds, ((R)PDI)CoN2, are effective precatalysts for the intramolecular [2π + 2π] cycloaddition of α,ω-dienes to yield the corresponding bicyclo[3.2.0]heptane derivatives. The reactions proceed under mild thermal conditions with unactivated alkenes, tolerating both amine and ether functional groups. The overall second order rate law for the reaction, first order with respect to both the cobalt precatalyst and the substrate, in combination with electron paramagnetic resonance (EPR) spectroscopic studies established the catalyst resting state as dependent on the identity of the precatalyst and diene substrate. Planar S = ½ κ(3)-bis(imino)pyridine cobalt alkene and tetrahedral κ(2)-bis(imino)pyridine cobalt diene complexes were observed by EPR spectroscopy and in the latter case structurally characterized. The hemilabile chelate facilitates conversion of a principally ligand-based singly occupied molecular orbital (SOMO) in the cobalt dinitrogen and alkene compounds to a metal-based SOMO in the diene intermediates, promoting C-C bond-forming oxidative cyclization. Structure-activity relationships on bis(imino)pyridine substitution were also established with 2,4,6-tricyclopentyl-substituted aryl groups, resulting in optimized catalytic [2π + 2π] cycloaddition. The cyclopentyl groups provide a sufficiently open metal coordination sphere that encourages substrate coordination while remaining large enough to promote a challenging, turnover-limiting C(sp(3))-C(sp(3)) reductive elimination.

  16. Modern Mathematics, Intelligence and Basic Conceptual Skills

    Williams, John D.


    The effect that learning modern'' mathematics (Dienes program) had on intelligence test scores of children aged eight and nine was studied. No overall significant difference was obtained between the experimental group and a control group instructed in a traditional mathematics program. (JP)

  17. Cytotoxic pregnane steroids from the seeds of Cipadessa baccifera (Roth.) Miq.

    Zhao, Lei; Zhang, Ping; Su, Xiao-Jie; Zhang, Bing


    A chemical investigation of the 80% ethanol extract of the seeds of Cipadessa baccifera (Roth.) Miq. led to the isolation of five new pregnane steroids, 17α,18,20S-trihydroxy-pregn-4-en-3,16-dione (1), 18-hydoxy-pregn-4,17(20)-trans-dien-3,16-dione (2), 3β,18-dihydroxy-pregn-5,17(20)-trans-dien-16-one (3), 2α,3β,4β,18-tetrahydroxy-pregn-5,17(20)-trans-dien-16-one (4), and 2α,3β,4β,17α,18,20S-hexahydroxy-pregn-5-en-16-one (5), along with two known compounds, 17α,20S-dihydroxy-pregn-4-en-3,16-dione (6) and 3β-hydroxy-pregn-5,17-dien-16-one (7). Structural elucidation of all the compounds was accomplished by spectral methods such as 1D and 2D NMR, IR, UV, and HRESIMS. The isolated compounds were tested in vitro for cytotoxic activities against seven tumor cell lines. As a result, pregnane-type steroids 1, 5 and 6 exhibited cytotoxicity with IC50 values <20μM against all tested tumor cell lines except meningioma cells (BEN-MEN-1).

  18. (+)-Geodin from Aspergillus terreus

    Rønnest, Mads Holger; Nielsen, Morten Thrane; Leber, Blanka


    The fungal metabolite (+)-geodin [systematic name: (2R)-methyl 5,7-dichloro-4-hydroxy-6'-methoxy-6-methyl-3,4'-dioxospiro[benzofuran-2,1'-cyclohexa-2',5'-diene]-2'-carboxylate], C(17)H(12)Cl(2)O(7), was isolated from Aspergillus terreus. The crystal structure contains two independent molecules...

  19. Effect of Multiwalled Carbon Nanotubes on the Properties of EPDM/NBR Dissimilar Elastomer Blends

    Hoikkanen, M.; Poikelispää, M.; Das, A.; Honkanen, M.; Dierkes, W.K.; Vuorinen, J.


    In the presence of multiwalled carbon nanotubes (MWCNT), polar nitrile-butadiene rubber (NBR) and nonpolar ethylene propylene diene rubber (EPDM) blends were prepared following a melt mixing method. For the preparation of MWCNT filled EPDM/NBR blends, two mixing methods were used: direct mixing and

  20. Antimicrobial effect of the Lingzhi or Reishi medicinal mushroom, Ganoderma lucidum (higher Basidiomycetes) and its main compounds.

    Vazirian, Mahdi; Faramarzi, Mohammad Ali; Ebrahimi, Seyed Esmaeil Sadat; Esfahani, Hamid Reza Monsef; Samadi, Nasrin; Hosseini, Seyed Aboulfazl; Asghari, Ali; Manayi, Azadeh; Mousazadeh, Ali; Asef, Mohammad Reza; Habibi, Emran; Amanzadeh, Yaghoub


    Mushrooms are considered one of the richest sources of natural antibiotics, and various species of them inhibit the growth of a wide diversity of microorganisms. Ganoderma lucidum, a well-known medicinal mushroom. has many pharmacological and biological activities including an antimicrobial effect, although few studies have investigated the antibacterial and antifungal effects of its purified compounds. The chemical structure of the purified compounds from the hexane fraction was elucidated as ergosta-7,22-dien-3β-yl acetate, ergosta-5,7,22-trien-3β-yl acetate (isopyrocalciferol acetate), ergosta-7,22-dien-3-one, ergosta-7,22-dien-3β-ol, and ergosta-5,7,22-trien-3β-ol (ergostrol). In addition, the structure of ganodermadiol was demonstrated after purification from the chloroform fraction. The fractions inhibited Gram-positive bacteria and yeast, with minimum inhibitory concentration values of 6.25 mg/mL, but were ineffective against Gram-negative bacteria in the tested concentrations. The results were comparable for isolated compounds, whereas the mixture of ergosta-7,22-dien-3β-yl acetate and isopyrocalciferol acetate was weakly effective against Escherichia coli (minimum inhibitory concentration, 10 mg/mL). It could be assumed that the antimicrobial effect of crude fractions is the consequence of mixing triterpenoid and steroid compounds.

  1. Minor sterols from the sponge Ircinia ramosa (Killer)

    Parameswaran, P.S.; Naik, C.G.; Das, B.; Kamat, S.Y.

    Three sterols, isolated from the lipid fraction of the sponge Ircinia ramosa were characterised as cholest-5-en-3 beta-ol-7-one (7-oxo cholesterol, 1), cholest 5-23-dien-b beta ol-7-one (7-oxo demosterol, 2) and 24E-ethyl cholest-5-en-3 beta -ol-7...

  2. [The role of pro- and antioxidant processes in the liver tissue of guinea pigs in pathogenesis of allergic alveolitis].

    Shchepans'kyĭ, F I; Reheda, M S


    It was shown that allergic alveolitis development is accompanied by increase of superoxyddismutase and catalase activity as well as an increase of dien conjugates and malonic dialdehyde content in Guinea pig liver. The administration of alfa-tokoferol acetate, an antioxidant resulted in decrease of these indices in the liver tissue that testifies its correcting influence upon PLO and antioxidant system processes.

  3. Technology & Mechanics Overview of Air-Inflated Fabric Structures


    bridging, and energy absorbers such as automotive air bags and landing cushions for space vehicles. Recent advances in high performance fibers and...inflated fabric structures were constructed using adhesively bonded, piece-cut manufacturing methods. These methods were limited to relatively low...moisture, fire, chemicals, etc. Coating materials such as urethane , PVC (poly vinyl chloride), neoprene, EPDM (ethylene propylene diene monomer) are

  4. Anti-human immunodeficiency virus-1 protease activity of new lanostane-type triterpenoids from Ganoderma sinense.

    Sato, Naoto; Zhang, Qun; Ma, Chao-Mei; Hattori, Masao


    Five new highly oxygenated lanostane-type triterpenoids [ganoderic acid GS-1 (1), ganoderic acid GS-2 (2), ganoderic acid GS-3 (3), 20(21)-dehydrolucidenic acid N (4) and 20-hydroxylucidenic acid A (5)] were isolated from the fruiting body of Ganoderma sinense, together with known compounds including 6 triterpenoids and 3 sterols. The structures of the new triterpenoids determined by spectroscopic means including 2D NMR were 7beta-hydroxy-3,11,15-trioxo-lanosta-8,24(E)-dien-26-oic acid (1), 7beta,15alpha-dihydroxy-3,11-dioxo-lanosta-8,24(E)-dien-26-oic acid (2), 12beta-acetoxy-3beta,7beta-dihydroxy-11,15-dioxo-lanosta-8,24(E)-dien-26-oic acid (3), 3beta,7beta-dihydroxy-11,15-dioxo-25,26,27-trinorlanosta-8,20-dien-24-oic acid (4), and 7beta,20xi-dihydroxy-3,11,15-trioxo-25,26,27-trinorlanost-8-en-24-oic acid (5), respectively. Among these, ganoderic acid GS-2, 20-hydroxylucidenic acid N, 20(21)-dehydrolucidenic acid N and ganoderiol F inhibited human immunodeficiency virus-1 protease with IC(50) values of 20-40 microM.

  5. Transformation Concepts for National Security in the 21st Century


    the types of reductions sought by the administration. The French crisis at Dien Bien Phu in the Spring of 1954 gave the New Look its first real test...his 2 years as Army Chief of Staff, Ridgway was persona non grata in the Eisenhower administration. His replacement, Taylor, brought a sophistication

  6. Toward an Air and Space Force: Can We Get There From Here? Naval Aviation and the Implications for Space Power


    5 Dramatis Personae : Rear Admiral William A. Moffett ................................................ 6...and influence, and the ones capable of shaping policy are the officers, especially those holding flag ranks. 6 Dramatis Personae : Rear Admiral William...Dien Bien Phu, and the Korean War influenced the perspectives of the cabinet members and essentially determined U.S. intervention policy.20 There is

  7. Claire Lee Chennault: Theorist and Campaign Planner


    at Dien Bien Phu. 7 The CIA eventually purchased his fleet and incorporated the clandestine air service into its operations. 8 Back in the dark days of...into a corner, finding himself persona non grata in both the Army and its air arm. He was dejected that the only sympathetic ear for his theories were

  8. Close Air Support: Which Way Do We Go?


    Reservoir fighting in 1950; outpost, column, and Parameters hamlet defense in Indochina and South Vietnam; and siege-breaking at Dien Bien Phu and Khe...Air Force has always sought leadership. It fits nicely their service persona . But is it in the Army’s interest to take over CAS, much less all of

  9. The DISAM Journal of International Security Assistance Management. Volume 30, Number 1, March 2008


    annexation of a little patch of ground called Sudetenland? Or a French defeat at a place called Dien Bien Phu? Or the return of an obscure cleric to...hitting it off”. • Present a calm, patient, even tempered persona . Avoid expressing classic type A traits. Expect to eventually reach your

  10. Southeast Asia Report, No. 1321.


    unlikely though not unwilling dramatis persona in the Be-ew refugee scenario, the violent and atrocious episodes of which the young governor of Abra has...ducted ceremonies commemorating the first phase of troop departure in the Dien Bien Phu campaign. These units are: Hanoi, Haiphong, Quang Nam-Da

  11. Essays on Strategy 6


    thereby setting an outer limit to US support for French commitments in the area. France’s defeat at Dien Bien Phu came and went. The French people wanted...traces the history of Japan’s economic develop- ment, analyzes its growth, and warns that Japan’s future rests on making decisions about the " persona of

  12. Journal of Special Operations Medicine, Volume 4, Edition 4, Fall 2004


    PERSONAE CARE - Cooperative for Assistance and Relief Everywhere CMOC - Civil Military Operations Center CRS - Catholic Relief Services DART...Duty Jack Singlaub (MG Ret) Hazardous Duty David H Hackworth (COL) & Tom Mathews Hell In A Very Small Place Bernard Fall (Siege of Dien Bien Phu) Ho

  13. Maleic-anhydride grafted EPM as compatibilising agent in NR/BR/EPDM blends

    Zhang, H.; Datta, R.N.; Talma, A.G.; Noordermeer, J.W.M.


    Incorporation of approximately 30 phr Ethylene–Propylene–Diene rubber (EPDM) into natural rubber (NR)/butadiene rubber (BR) is a means to achieve non-staining ozone resistance for tire sidewall applications. However, due to incompatibility of the elastomers and heterogeneous filler distribution in e

  14. Aroma profiles of vegetable oils varying in fatty acid composition vs. concentrations of primary and secondary lipid oxidation products

    Ruth, van S.M.; Roozen, J.P.; Jansen, F.J.H.M.


    The aroma compositions of oxidised sunflower oil, linseed oil and a blend thereof (85/15) were compared with frequently used indicators for primary and secondary lipid oxidation. Primary lipid oxidation was followed by the formation of conjugated dienes, secondary lipid oxidation by proponal and

  15. Excretion balance and metabolism of the progestagen Org 30659 in healthy postmenopausal women

    Verhoeven, CHJ; Gloudemans, RHM; Groothuis, GMM; Rietjens, IMCM; Vos, RME


    Metabolism of Org 30659 ((17 alpha)-17-hydroxy-11-methylene-19-norpregna-4,15-dien-20-yn-3-one), a new potent progestagen currently under clinical development by NV Organon for use in oral contraception and hormone replacement therapy was studied in vivo after oral administration to healthy postmeno

  16. Solvent Effects in Asymmetric Hetero Diels-Alder and Ene Reactions

    Johannsen, Mogens; Jørgensen, Karl Anker


    The use of polar solvents such as nitromethane or 2-nitropropane leads to a significant improvement of the catalytic properties of a cationic copper-Lewis acid in the hetero Diels-Alder reaction of alkyl glyoxylates with dienes; The scope of a newly developed copper(II)-bisoxazoline catalyst...

  17. Iodine, a Mild Reagent for the Aromatization of Terpenoids.

    Domingo, Victoriano; Prieto, Consuelo; Silva, Lucia; Rodilla, Jesús M L; Quílez del Moral, José F; Barrero, Alejandro F


    Efficient procedures based on the use of iodine for the aromatization of a series of terpenoids possessing diene and homoallylic or allylic alcohol functionalities are described. Different examples are reported as a proof-of-concept study. Furthermore, iodine also proved to mediate the dehydrogenation of testosterone.

  18. New phenolic esters from the resinous exudate of Haplopappus taeda.

    Faini, Francesca; Labbé, Cecilia; Torres, René; Rodilla, Jesús M; Silva, Lucía; Delle Monache, Franco


    Two new phenolic esters 9-trans-p-coumaroyloxy-alpha-terpineol (1) and 7-trans-p-coumaroyloxy-taedol (2), both endowed with free radical scavenger activity and cleroda-3,13 (E)-dien-15,18-diol (3) for which a cis stereochemistry at the decalin junction was found, were isolated from the resinous exudate from Haplopappus taeda upper parts.

  19. Genetic differentiation between African and European Midwife Toads (Alytes, Discoglossidae)

    Arntzen, J.W.; Szymura, J.M.


    Toads of the genus Alytes from the Rif mountains in Morocco are electrophoretically very similar to Iberian Alytes obstetricans (DieN = 0.07). Genetic distance estimates across the Straits of Gibraltar do not exceed the values found among European samples. The data point to relatively recent coloniz

  20. Cytotoxic Activity and G1 Cell Cycle Arrest of a Dienynone from Echinacea pallida

    Chicca, Andrea; Adinolfi, Barbara; Pellati, Federica;


    In the present study, a further investigation of the cytotoxic activity of an acetylenic constituent of ECHINACEA PALLIDA roots, namely, pentadeca-(8 Z,13 Z)-dien-11-yn-2-one, was performed, revealing a concentration-dependent cytotoxicity on several human cancer cell lines, including leukemia...

  1. Face-selective Diels-Alder reactions between unsymmetrical cyclohexadienes and symmetric trans-dienophile: an experimental and computational investigation.

    Lahiri, Saswati; Yadav, Somnath; Banerjee, Srirupa; Patil, Mahendra P; Sunoj, Raghavan B


    A combined experimental and theoretical study of the Diels-Alder reactions between 2-trimethylsiloxy-1,3-cyclohexadienes (2-11) and (E)-1,4-diphenylbut-2-ene-1,4-dione (1) is reported. Two diastereomeric products, 5-endo-6-exo- (nx) and 5-exo-6-endo- (xn) dibenzoyl derivatives, are possible with symmetric trans-dienophile (1). While in many cases 5-endo-6-exo product is preferred over the corresponding 5-exo-6-endo product, the product ratio nx:xn is found to vary with the position of substituents on the diene. The density functional theory studies with the mPW1PW91/6-31G* as well as the B3LYP/6-31G* levels reveal that the electrostatic repulsion between the oxygen lone pairs on the diene and the dienophile is critical to the observed product selectivities. The optimized transition state geometries though appeared to involve secondary orbital interactions, careful examination of the frontier Kohn-Sham orbitals as well as calculations with the natural bond orbital (NBO) analyses confirm the absence of SOI in these transition states. In the case of methyl-substituted dienes, a cumulative effect of steric and electrostatic interactions between the diene and the dienophile is found to be the controlling element toward the observed selectivity.

  2. Valence isomerization of cyclohepta-1,3,5-triene and its heteroelement analogues

    Helen Jansen


    Full Text Available The valence isomerization of the all-carbon and heteroelement analogues of cyclohepta-1,3,5-triene into the corresponding bicyclo[4.1.0]hepta-2,4-dienes is reviewed to show the impact of the heteroatom on the stability of both valence isomers. The focus is on the parent systems and their synthetic applications.


    LOVELL, K.


  4. The Evaluation of Three Maths Courses

    Williams, John D.


    Cuisenaire, Dienes and traditional methods of teaching mathematics were compared by pre- and posttesting pupils in British junior schools during a three year period (1961-63) on mechanical and problem arithmetic, concept knowledge and attitudes. Details of the varied experimental design are given in addition to data and interpretation. (JP)

  5. Mathematical Analysis of Piaget's Grouping Concept. Papy's Minicomputer as a Grouping

    Steiner, H. G.


    Through a mathematical analysis, Piaget's grouping concept can be formally interpreted as being a hybrid between the mathematical concepts of a group and a lattice. Some relevant pedagogical models are presented. Activities with Cuisenaire Rods, Dienes Blocks, and Papy's Minicomputer are shown to take place in groupings. (LS)

  6. Elastomers with Reversible Nanoporosity

    Szewczykowski, Piotr Przemyslaw; Andersen, K.; Schulte, Lars;


    An elastomer was created via cross-linking a diene block of a polyisoprene-polydimethylsiloxane (PI-PDMS) block copolymer in the ordered state of hexagonal morphology, followed by the quantitative removal of the PDMS component. The elastomer material collapsed following etching of the PDMS...

  7. Crystal structures and photoelectron spectra of some trimethanoanthracenes, tetramethanonaphthacenes, and pentamethanopentacenes. Experimental evidence for laticyclic hyperconjugation

    Paddon-Row, Michael N.; Englehardt, Lutz M.; Skelton, Brian W.


    Photoelectron (p.e.) spectra of the series of dienes (), (), ()-(), and crystal structures for the dodecachlorodienes()-() are reported. The spectra revealed large [small pi]-splitting energies of 0.32 and 0.52 eV for () and () respectively. The value of () is attributed to the presence of orbita...

  8. Algunos componentes esteroidales del solanum havanense jacq

    Mario J. Basterrechea Rey


    Full Text Available Un nuevo alcaloide esteroidal llamado acetil etiolina, ha sido aislado de las hojas, tallos y raices del Solanum havanense Jacq y su estructura corresponde con (25S-16a-acetoxi-22.26-epiminocolest-5.22(N-dien-3ß-ol.

  9. Chemical constituents of marine algal-derived endophytic fungus Exophiala oligosperma EN-21

    Li, Fang; Li, Ke; Li, Xiaoming; Wang, Bingui


    Seven compounds (1-7) were identified from the cultivation of the endophytic fungus Exophiala oligosperma (EN-21) that was isolated from the inner tissue of the marine red alga Laurencia similis. Their structures were identified with spectroscopic and chemical methods as 2-phenoxynaphthalene ( 1), (2 S, 3 R, 4 E, 8 E)-1- O-β-D-glucopyranosyl-3-hydroxy-2-[( R)-2'-hydroxyoctadecanoyl] amino-9-methyl-4, 8-octadeca-diene ( 2), (22 E,24 R)-ergosta-7,22-dien-3β,5α,6β-triol ( 3), (22 E, 24 R)-3β, 5α, 9α-trihydroxy-ergosta-7, 22-dien-6-one ( 4), (22 E, 24 R)-5α, 6α-epoxy-ergosta-8, 22-dien-3β, 7α-diol ( 5), (22 E, 24 R)-ergosta-4, 6, 8(14), 22-tetraen-3-one ( 6), and euphorbol ( 7). This paper reports for the first time the chemical constituents of fungus Exophiala oligosperma and the discovery of compound 1 as a natural product from the fungus.

  10. Chemical constituents of marine algal-derived endophytic fungus Exophiala oligosperma EN-21

    LI Fang; LI Ke; LI Xiaoming; WANG Bingui


    Seven compounds (1-7) were identified from the cultivation of the endophytic fungus Exophiala oligosperma (EN-21) that was isolated from the inner tissue of the marine red alga Laurencia similis. Their structures were identified with spectroscopic and chemical methods as 2-phenoxynaphthalene (1), (2S, 3R, 4E, 8E)-l-O-β-D-glucopyranosyl-3-hydroxy-2-[(R)-2'-hydroxyoctadecanoyl] amino-9-methyl-4, 8-octadeca-diene (2), (22E,24R)-ergosta-7,22-dien-3β,5α,6β-triol (3), (22E, 24R)-3β, 5α, 9α-trihydroxy-ergosta-7, 22-dien-6-one (4), (22E, 24R)-5α, 6α-epoxy-ergosta-8, 22-dien-3β 7伪-diol (5), (22E, 24R)-ergosta-4, 6, 8(14), 22-tetraen-3-one (6), and euphorbol (7). This paper reports for the first time the chemical constituents of fungus Exophiala oligosperma and the discovery of compound 1 as a natural product from the fungus.

  11. Family Fathers Lost in Theatre Paradox

    Kuhlmann, Annelis


    Diderot's influence on theatre is well known through The Paradox of Acting (Paradoxe sur le comédien). However, Diderot also wrote a few drames bourgeois, among which is The Family Father (Le Père de famille), which still in Diderot's days was edited in Copenhagen in French, and which in Danish...

  12. EPDM as a selective membrane material in pervaporation

    Meuleman, E.E.B.; Willemsen, J.H.A.; Mulder, M.H.V.; Strathmann, H.


    Various types of ethylene-propylene-diene terpolymers (EPDM) and crosslinking procedures have been investigated with pervaporation, vapor sorption, liquid sorption and gas permeation experiments. The EPDM parameters that have been changed are ethylene content, molecular weight, choice of third monom

  13. Multistep Synthesis of a Terphenyl Derivative Showcasing the Diels-Alder Reaction

    Davie, Elizabeth A. Colby


    An adaptable multistep synthesis project designed for the culmination of a second-year organic chemistry laboratory course is described. The target compound is a terphenyl derivative that is an intermediate in the synthesis of compounds used in organic light-emitting devices. Students react a conjugated diene with dimethylacetylene dicarboxylate…

  14. EPDM rubber reclaim from devulcanized EPDM

    Sutanto, P.; Picchioni, F.; Janssen, L. P. B. M.; Dijkhuis, K. A. J.; Dierkes, W. K.; Noordermeer, J. W. M.


    Two types of ethylene-propylene-diene monomer (EPDM) rubbers, namely an efficient vulcanized (EV) and a serniefficient vulcanized (SEV), have been used to produce devulcanizates in a continuous setup. The devulcanizates are re-cured using the same recipes as for the virgin rubber. The influence of m

  15. Teaching Experiment: The Effect of Manipulatives in Second Graders' Learning of Mathematics, Volume I. PMDC Technical Report No. 11.

    Behr, Merlyn J.

    This teaching experiment investigated variables which affect how well children learn from manipulative aids and how to use such aids in teaching mathematics. Five small groups from one second-grade classroom were stratified by achievement and taught using (1) counting sticks; (2) Dienes blocks; (3) abacus; (4) all three materials; or (5) counting…

  16. Cooperative catalysis with first-row late transition metals

    J.I. van der Vlugt


    Cooperative catalysis with first-row transition metals holds much promise for future developments regarding sustainable, selective transformations, including e.g. alkenes, dienes and a variety of small molecules such as CO2, N2 and water. This non-exhaustive analysis of the current state-of-the-art

  17. Food matrices affect the bioavailability of (n-3) polyunsaturated fatty acids in a single meal study in humans

    Schram, Laurine B; Nielsen, Carina J.; Porsgaard, Trine


    , a yoghurt drink, eight oil capsules, bread and butter; 4 g of fish oil was incorporated into one of the matrices. Blood samples were collected and fatty acid composition of chylomicrons was determined together with plasma levels of conjugated dienes and alpha-tocopherol. Fish oil incorporated into food...

  18. Oxidizability of unsaturated fatty acids and of a non-phenolic lignin structure in the manganese peroxidase-dependent lipid peroxidation system

    Alexander N. Kapich; Tatyana V. Korneichik; Annele Hatakka; Kenneth E. Hammel


    Unsaturated fatty acids have been proposed to mediate the oxidation of recalcitrant, non-phenolic lignin structures by fungal manganese peroxidases (MnP), but their precise role remains unknown. We investigated the oxidizability of three fatty acids with varying degrees of polyunsaturation (linoleic, linolenic, and arachidonic acids) by measuring conjugated dienes...

  19. Convergent Synthesis of Pancratistatin from Piperonal and Xylose

    Dam, Johan Hygum; Madsen, Robert


    to afford a highly functionalised 1,7-diene, which is then converted into the corresponding cyclohexene by ring-closing olefin metathesis. Subsequent Overman rearrangement, dihydroxylation and deprotection afford the natural product in a total of 25 steps from the two starting materials. The longest linear...

  20. Synthesis of Gabosine A and N from Ribose by the Use of Ring-Closing Metathesis

    Monrad, Rune Nygaard; Fanefjord, Mette; Hansen, Flemming Gundorph;


    -methylallyl bromide. The functionalized octa-1,7-diene, thus obtained, is converted into the six-membered gabosine skeleton by ring-closing olefin metathesis. Subsequent protective group manipulations and oxidation gives rise to gabosine N in a total of 8 steps from ribose while the synthesis of gabosine...

  1. Efficient synthesis of enantiopure conduritols by ring-closing metathesis

    Jørgensen, Morten; Iversen, Erik Høgh; Paulsen, Andreas Lundtang;


    Two short synthetic approaches to enantiopure conduritols are described starting from the chiral pool. In both cases, the cyclohexene ring is assembled via ring-closing olefin metathesis. The terminal diene precursers for the metathesis reaction are prepared either from octitols or from tartaric...

  2. New library of aminosulfonyl-tagged Hoveyda–Grubbs type complexes: Synthesis, kinetic studies and activity in olefin metathesis transformations

    Etienne Borré


    Full Text Available Seven novel Hoveyda–Grubbs precatalysts bearing an aminosulfonyl function are reported. Kinetic studies indicate an activity enhancement compared to Hoveyda’s precatalyst. A selection of these catalysts was investigated with various substrates in ring-closing metathesis of dienes or enynes and cross metathesis. The results demonstrate that these catalysts show a good tolerance to various chemical functions.

  3. Industrial processes of olefin metathesis. Pt. 1

    Warwel, S.


    Olefin metathesis opens new synthetic routes to typical petrochemicals (ethylene, propylene, n-butenes), special olefins (neohexene, higher molecular linear olefins, , -dienes) and unsaturated polymers (polynorbornene, -cyclooctene, -dicyclopentadiene) in an industrial scale. The 8 metathesis processes used in industry and further possible applications of olefin metathesis are reviewed.

  4. New library of aminosulfonyl-tagged Hoveyda–Grubbs type complexes: Synthesis, kinetic studies and activity in olefin metathesis transformations

    Borré, Etienne; Caijo, Frederic


    Summary Seven novel Hoveyda–Grubbs precatalysts bearing an aminosulfonyl function are reported. Kinetic studies indicate an activity enhancement compared to Hoveyda’s precatalyst. A selection of these catalysts was investigated with various substrates in ring-closing metathesis of dienes or enynes and cross metathesis. The results demonstrate that these catalysts show a good tolerance to various chemical functions. PMID:21165173

  5. Cicloadições [3+4] via cátions oxialílicos: aplicações em sínteses orgânicas [3+4]Cycloadditions via oxyallyl cations: applications in organic synthesis

    Antônio Jacinto Demuner


    Full Text Available Several methodologies for the generation of oxyallyl cations from polybromoketones and other substrates are discussed. The mechanistic aspect of the [3+4] cycloaddition reaction between these cations and dienes leading to the formation of seven membered ring carbocyclic compounds is presented. Finally, some synthetic applications of the [3+4] cycloaddition are shown.

  6. Simple, chemoselective, catalytic olefin isomerization.

    Crossley, Steven W M; Barabé, Francis; Shenvi, Ryan A


    Catalytic amounts of Co(Sal(tBu,tBu))Cl and organosilane irreversibly isomerize terminal alkenes by one position. The same catalysts effect cycloisomerization of dienes and retrocycloisomerization of strained rings. Strong Lewis bases like amines and imidazoles, and labile functionalities like epoxides, are tolerated.

  7. On the relationship between structure and reaction rate in olefin ring-closing metathesis.

    Ashworth, Ian W; Carboni, Davide; Hillier, Ian H; Nelson, David J; Percy, Jonathan M; Rinaudo, Giuseppe; Vincent, Mark A


    In the RCM reactions of a series of simple α,ω-dienes, the relative order of reactivity has been unambiguously determined showing that cyclohexene forms faster than cyclopentene or cycloheptene. 1,5-Hexadiene inhibits the RCM of 1,7-octadiene; 1,5-hexadiene cannot progress to the RCM product (cyclobutene) but forms an unexpectedly stable cyclic η(2)-complex.

  8. EPDM as a selective membrane material in pervaporation

    Meuleman, E.E.B.; Willemsen, J.H.A.; Mulder, M.H.V.; Strathmann, H.


    Various types of ethylene-propylene-diene terpolymers (EPDM) and crosslinking procedures have been investigated with pervaporation, vapor sorption, liquid sorption and gas permeation experiments. The EPDM parameters that have been changed are ethylene content, molecular weight, choice of third monom

  9. EPDM as a selective membrane material in pervaporation

    Meuleman, E.E.B.; Willemsen, J.H.A.; Mulder, M.H.V.; Strathmann, H.


    Various types of ethylene–propylene-diene terpolymers (EPDM) and crosslinking procedures have been investigated with pervaporation, vapor sorption, liquid sorption and gas permeation experiments. The EPDM parameters that have been changed are ethylene content, molecular weight, choice of third monom

  10. SwissProt search result: AK119442 [KOME

    Full Text Available AK119442 001-133-C06 (Q38710) Abietadiene synthase, chloroplast precursor ((-)-abieta...-7(8),13(14)-diene synthase) (Abietadiene cyclase) (Agggabi) [Includes: Abietadiene synthase (EC; Copalyl diphosphate synthase (EC] TPSDV_ABIGR 1e-89 ...

  11. SwissProt search result: AK110925 [KOME

    Full Text Available AK110925 002-173-D07 (Q38710) Abietadiene synthase, chloroplast precursor ((-)-abieta...-7(8),13(14)-diene synthase) (Abietadiene cyclase) (Agggabi) [Includes: Abietadiene synthase (EC; Copalyl diphosphate synthase (EC] TPSDV_ABIGR 9e-46 ...

  12. SwissProt search result: AK241679 [KOME

    Full Text Available AK241679 J065193F24 (Q38710) Abietadiene synthase, chloroplast precursor ((-)-abieta...-7(8),13(14)-diene synthase) (Abietadiene cyclase) (Agggabi) [Includes: Abietadiene synthase (EC; Copalyl diphosphate synthase (EC] TPSDV_ABIGR 1e-49 ...

  13. SwissProt search result: AK068923 [KOME

    Full Text Available AK068923 J013170A09 (Q38710) Abietadiene synthase, chloroplast precursor ((-)-abieta...-7(8),13(14)-diene synthase) (Abietadiene cyclase) (Agggabi) [Includes: Abietadiene synthase (EC; Copalyl diphosphate synthase (EC] TPSDV_ABIGR 7e-12 ...

  14. SwissProt search result: AK100631 [KOME

    Full Text Available AK100631 J023109E08 (Q38710) Abietadiene synthase, chloroplast precursor ((-)-abieta...-7(8),13(14)-diene synthase) (Abietadiene cyclase) (Agggabi) [Includes: Abietadiene synthase (EC; Copalyl diphosphate synthase (EC] TPSDV_ABIGR 1e-123 ...

  15. SwissProt search result: AK070116 [KOME

    Full Text Available AK070116 J023043P03 (Q38710) Abietadiene synthase, chloroplast precursor ((-)-abieta...-7(8),13(14)-diene synthase) (Abietadiene cyclase) (Agggabi) [Includes: Abietadiene synthase (EC; Copalyl diphosphate synthase (EC] TPSDV_ABIGR 2e-29 ...

  16. SwissProt search result: AK121446 [KOME

    Full Text Available AK121446 J023141H19 (Q38710) Abietadiene synthase, chloroplast precursor ((-)-abieta...-7(8),13(14)-diene synthase) (Abietadiene cyclase) (Agggabi) [Includes: Abietadiene synthase (EC; Copalyl diphosphate synthase (EC] TPSDV_ABIGR 3e-29 ...

  17. SwissProt search result: AK065109 [KOME

    Full Text Available AK065109 J013001N21 (Q38710) Abietadiene synthase, chloroplast precursor ((-)-abieta...-7(8),13(14)-diene synthase) (Abietadiene cyclase) (Agggabi) [Includes: Abietadiene synthase (EC; Copalyl diphosphate synthase (EC] TPSDV_ABIGR 2e-44 ...

  18. SwissProt search result: AK119327 [KOME

    Full Text Available AK119327 001-131-B02 (Q38710) Abietadiene synthase, chloroplast precursor ((-)-abieta...-7(8),13(14)-diene synthase) (Abietadiene cyclase) (Agggabi) [Includes: Abietadiene synthase (EC; Copalyl diphosphate synthase (EC] TPSDV_ABIGR 2e-59 ...

  19. SwissProt search result: AK241330 [KOME

    Full Text Available AK241330 J065144B19 (Q38710) Abietadiene synthase, chloroplast precursor ((-)-abieta...-7(8),13(14)-diene synthase) (Abietadiene cyclase) (Agggabi) [Includes: Abietadiene synthase (EC; Copalyl diphosphate synthase (EC] TPSDV_ABIGR 2e-46 ...

  20. SwissProt search result: AK242212 [KOME

    Full Text Available AK242212 J075171E13 (Q38710) Abietadiene synthase, chloroplast precursor ((-)-abieta...-7(8),13(14)-diene synthase) (Abietadiene cyclase) (Agggabi) [Includes: Abietadiene synthase (EC; Copalyl diphosphate synthase (EC] TPSDV_ABIGR 4e-22 ...

  1. SwissProt search result: AK121319 [KOME

    Full Text Available AK121319 J023113P09 (Q38710) Abietadiene synthase, chloroplast precursor ((-)-abieta...-7(8),13(14)-diene synthase) (Abietadiene cyclase) (Agggabi) [Includes: Abietadiene synthase (EC; Copalyl diphosphate synthase (EC] TPSDV_ABIGR 2e-57 ...

  2. SwissProt search result: AK062280 [KOME

    Full Text Available AK062280 001-100-C03 (Q38710) Abietadiene synthase, chloroplast precursor ((-)-abieta...-7(8),13(14)-diene synthase) (Abietadiene cyclase) (Agggabi) [Includes: Abietadiene synthase (EC; Copalyl diphosphate synthase (EC] TPSDV_ABIGR 2e-43 ...

  3. SwissProt search result: AK072461 [KOME

    Full Text Available AK072461 J023116G20 (Q38710) Abietadiene synthase, chloroplast precursor ((-)-abieta...-7(8),13(14)-diene synthase) (Abietadiene cyclase) (Agggabi) [Includes: Abietadiene synthase (EC; Copalyl diphosphate synthase (EC] TPSDV_ABIGR 7e-65 ...

  4. SwissProt search result: AK068310 [KOME

    Full Text Available AK068310 J013149A01 (Q38710) Abietadiene synthase, chloroplast precursor ((-)-abieta...-7(8),13(14)-diene synthase) (Abietadiene cyclase) (Agggabi) [Includes: Abietadiene synthase (EC; Copalyl diphosphate synthase (EC] TPSDV_ABIGR 4e-91 ...

  5. SwissProt search result: AK072928 [KOME

    Full Text Available AK072928 J023144G04 (Q38710) Abietadiene synthase, chloroplast precursor ((-)-abieta...-7(8),13(14)-diene synthase) (Abietadiene cyclase) (Agggabi) [Includes: Abietadiene synthase (EC; Copalyl diphosphate synthase (EC] TPSDV_ABIGR 4e-22 ...

  6. SwissProt search result: AK108761 [KOME

    Full Text Available AK108761 002-150-G06 (Q38710) Abietadiene synthase, chloroplast precursor ((-)-abieta...-7(8),13(14)-diene synthase) (Abietadiene cyclase) (Agggabi) [Includes: Abietadiene synthase (EC; Copalyl diphosphate synthase (EC] TPSDV_ABIGR 3e-19 ...

  7. SwissProt search result: AK100333 [KOME

    Full Text Available AK100333 J023080N01 (Q38710) Abietadiene synthase, chloroplast precursor ((-)-abieta...-7(8),13(14)-diene synthase) (Abietadiene cyclase) (Agggabi) [Includes: Abietadiene synthase (EC; Copalyl diphosphate synthase (EC] TPSDV_ABIGR 1e-141 ...

  8. SwissProt search result: AK071447 [KOME

    Full Text Available AK071447 J023097D21 (Q38710) Abietadiene synthase, chloroplast precursor ((-)-abieta...-7(8),13(14)-diene synthase) (Abietadiene cyclase) (Agggabi) [Includes: Abietadiene synthase (EC; Copalyl diphosphate synthase (EC] TPSDV_ABIGR 1e-43 ...

  9. SwissProt search result: AK066759 [KOME

    Full Text Available AK066759 J013077H13 (Q38710) Abietadiene synthase, chloroplast precursor ((-)-abieta...-7(8),13(14)-diene synthase) (Abietadiene cyclase) (Agggabi) [Includes: Abietadiene synthase (EC; Copalyl diphosphate synthase (EC] TPSDV_ABIGR 4e-64 ...

  10. SwissProt search result: AK108710 [KOME

    Full Text Available AK108710 002-150-A11 (Q38710) Abietadiene synthase, chloroplast precursor ((-)-abieta...-7(8),13(14)-diene synthase) (Abietadiene cyclase) (Agggabi) [Includes: Abietadiene synthase (EC; Copalyl diphosphate synthase (EC] TPSDV_ABIGR 5e-21 ...

  11. Het vrijheidsbegrip bij J. G. Fichte : een critische analyse naar aanleiding van Fichte's hoofdwerken uit zijn eerste periode

    Frederikse, Theodoor Christiaan


    Joahnn Gottlieb Fichte was wijsgeer. Zijn filosofie heeft steeds slechts in zeer geringe mate de interesse van theologische zijde gewekt. Namen als van E. Hirsch en F. Gogarten (in diens eerste periode) zijn de uitzonderingen die de regel bevestigen. De redenen hiervoor zijn niet moeilijk aan te wij

  12. Sterol composition from inflorescences of Hieracium pilosella L.

    Tadeusz Krzaczek


    Full Text Available The fraction of sterol acetates from the inflorescences of Hieracium pilosella has been isolated in the typical way from petroleum ether extract. By means of the weight method the total amount of sterols was determined (0.2659%. The mixtures of sterol acetates and free sterols were investigated using GC-MS techniques. The occurrence of about 18 sterols has been observed. Cholesterol, cholest-8(14-en-3b-ol, cholesta-5.7-dien-3b-ol, cholest-7-en-3b-ol, ergosta-5.24-dien-3b-ol, campesterol, stigmasterol, b-sitosterol, fucosterol, 5a-stigmast-7-en-3a-ol were identified. The probable structures of lophenol, isofucosterol, 5a-stigmasta-7.24-dien-3b-ol, lanosta-9(11.24-dien-3b-ol and 24-ethylidene lophenol were stated on the basis of literature data. The last 4 sterols occur in a vestigial quantity, which made its identification impossible. Sitos erol and cholesterol are remarkably dominating sterols in the fraction.


    31 Okt 1977 ... totstandkoming van die mediese diens is aan It- kol M,C, Roland ... mediese hulp aan verskeie regi- mente op die Rand te gee, Lt-kol D,W, Johnston. 38 .... lent work you have done with us, all of it con- structive and under the ...

  14. New diterpenes from the heartwood of Chamaecyparis obtusa var. formosana.

    Kuo, Y H; Chen, C H; Huang, S L


    An abietane diterpene, 11,14-dihydroxy-8,11,13-abietatrien-7-one (1); a seco-abietane diterpene, obtuanhydride (2); and an isopimarane diterpene, 18,19-O-isopropylidene-18, 19-dihydroxyisopimara-8(14),15-diene (3) were isolated from the heartwood of Chamaecyparis obtusa var. formosana. The structures of these new compounds were elucidated by spectroscopic methods.

  15. Een oude vondst op Java van de Groote Aalscholver (Phalacrocorax sulcirostris territori (Math.) in het museum te Buitenzorg

    Hoogerwerf, A.


    In De Tropische Natuur (jrg. 24, Juni 1935, p. 90/91) maakten wij, bij een goede foto der levende volgels, melding van een groote aalscholver door ons in 1935 waargenomen in de Brantas-delta, die later bleek Phalacrocorax sulcirostris territori te zijn en door ons onder dien naam werd gepubliceerd i

  16. Biotransformation of a cage-like diels-alder adduct and derivatives by Mucor ramosissimus samutsevitsch

    Ito, Felicia Megumi; Mena, Ana Elisa Maciel; Marques, Maria Rita; de Lima, Dênis Pires; Beatriz, Adilson


    The present study aimed to evaluate the ability for biotransformation of the Diels-Alder adduct tricyclo[,7]undeca-4,9-dien-3,6-dione (1) and two synthetic derivatives by the saprobe fungus Mucor ramosissimus Samutsevitsch. Products from oxidation, isomerization and, regioselective and enantioselective reduction were achieved. PMID:24031400

  17. Catalytic applications of mono- and dinuclear complexes containing metal-carbon sigma bonds. Final report, November 1, 1993--October 31, 1996

    Norton, J.R.


    This report discusses results from several studies involved in the project. Investigations include: vibrational models for surface olefins and alkylidenes; mechanism of the formation and fragmentation of diosmacyclobutanes; reaction of dienes and allenes with diosmacyclobutanes; determination by nematic phase NMR of the structure of mononuclear and dinuclear ethylene complexes of osmium; and generation of ``coordinatively unsaturated`` complexes by protonation of methyl osmium complexes.

  18. [Content of biological antioxidants and lipid peroxidation in the adrenal cortex in experimental circulatory insufficiency].

    Doroshkevich, N A; Antsulevich, S N; Nadol'nik, L I; Naumov, A V; Beluga, V B; Vinogradov, V V


    Thirteen-week experimental insufficiency in rats causes exhaustion of adrenal cortex function. The number of diene conjugates in the adrenals increased, the alpha-tocopherol level decreased. It is suggested that reduced level of antioxidant protection and the associated activation of lipid peroxidation processes underlie the disorders of adrenal cortex function.

  19. New Polytetrahydrofuran Graft Copolymers.


    chioroprene) , chiorobutyl - ~~~~~ rubber , bromobutyl rubber , chlorinated EPDM , chlorinated poly(buta— diene) and chlorinated butadiene styrene copolymer...for initial detailed studies (3 ,4 , 6 , 7 — 9 ) . Many soluble metal salts with cations capable of stabilizing an on].um ion polymerization (SO3CF 3

  20. Development of a Cavitation Erosion Resistant Advanced Material System


    Ethylene Propylene Diene Monomer ( EPDM ) based Elastomers ........ 45 5.3.2 Fluorinated Elastom ers...Sheet EPD M results .............................................................................. 47 Figure 5.11 - EPDM rubber samples, sheet (left...a common end grain balsa in Table 3.3. Polyvinyl foam cores are manufactured by combining a polyvinyl copolymer with stabilizers , plasticizers

  1. Sulfoxide-directed intramolecular [4 + 2] cycloadditions between 2-sulfinyl butadienes and unactivated alkynes.

    Fernández de la Pradilla, Roberto; Tortosa, Mariola; Castellanos, Esther; Viso, Alma; Baile, Raquel


    Sulfinyl dienynes undergo thermal and catalyzed IMDA cycloadditions, often at room temperature, to produce cyclohexa-1,4-dienes with good yields and high selectivities. Additionally, the products preserve a synthetically useful vinyl sulfoxide functionality. The selective manipulation of the double bonds in the cycloadducts has also been examined in this work.

  2. Phytochemistry and in vitro pharmacological activities of South African Vitex (Verbenaceae) species

    Nyiligira, E


    Full Text Available was purified to give a labdane diterpene as an inseparable epimeric mixture of 12S,16S/R-dihydroxy-ent-labda-7,13-dien-15,16-olide. Cirsimaritin was also isolated and identified from V. rehmannii. All the species, apart from V. zeyheri, exhibited scavenging...

  3. Antiparasitic, Nematicidal and Antifouling Constituents from Juniperus Berries

    A bioassay-guided fractionation of Juniperus procera berries yielded antiparasitic, nematicidal and antifouling constituents, including a wide range of known abietane, pimarane and labdane diterpenes. Among these, abieta-7,13-diene (1) demonstrated in vitro antimalarial activity against Plasmodium f...

  4. Effect of Sulfurization Temperature on Thioetheriifcation Performance of Mo-Ni/Al2O3 Catalyst

    Shen Zhibing; Ke Ming; Ren Tao; Zhang Juntao; Liang Shengrong


    The Mo modiifed Ni/Al2O3 catalysts were prepared and sulifded at different temperatures, and their catalytic acti-vity for thioetheriifcation of mercaptans and oleifns (or dienes), hydrogenation of dienes and oleifns in the thioetheriifcation process using lfuidized catalytic cracking (FCC) naphtha as the feedstock was investigated. In order to disclose the correla-tion between the physicochemical characteristics of catalysts and their catalytic activity, the surface structures and properties of the catalysts sulifded at different temperatures were characterized by the high resolution transmission electronic micro-scopy (HRTEM), X-ray photoelectron spectroscopy (XPS) and H2-temperature programmed reduction (H2-TPR) technique. The results showed that an increase of sulfurization temperature not only could promote the sulfurization degree of active metals on the catalysts, but also could adjust the micro-morphology of active species. These changes could improve the catalytic performance of thioetheriifcation, and hydrogenation of dienes and oleifns. However, an excess sulfurization tem-perature was more easily to upgrade the ability of the catalyst for hydrogenation of oleifns, which could lead to a decrease of the octane number of the product. It was also showed that a moderate sulfurization temperature not only could improve the catalytic performance of thioetheriifcation and hydrogenation of dienes but also could control hydrogenation of oleifns.

  5. Volatile non-terpenoid hydrocarbons from Ligusticum grayi roots

    The root essential oil of Ligusticum grayi Coult. & Rose (Apiaceae) contains three volatile non-terpenoid hydrocarbons: the known C11 compound viridene, whose structure is hereby corrected to 1-[(2Z)-pent-2-en-1-yl]cyclohexa-1,3-diene; and the heretofore unreported C10 compounds 1-[(2Z)-but-2-en-1-y...

  6. Understanding Roofing Systems.

    Michelsen, Ted


    Reviews the various types of multi- and single-ply roofing commonly used today in educational facilities. Roofing types described involve built-up systems, modified bitumen systems; ethylene propylene diene terpolymer roofs; and roofs of thermoplastic, metal, and foam. A description of the Roofing Industry Educational Institute is included. (GR)

  7. Stereoselective synthesis of monofluoroalkyl α,β-unsaturated ketones from allenyl carbinol esters mediated by gold and Selectfluor.

    Jin, Zhuang; Hidinger, Rachel S; Xu, Bo; Hammond, Gerald B


    Allenyl carbinol ester 3 isomerizes to an E,Z mixture of the corresponding diene 2 in the presence of gold catalyst 4, but the resulting mixture yields monofluoroalkyl α,β-unsaturated ketone 1 with exclusive E selectivity and in high yields after reaction with Selectfluor.

  8. The influence of the injection molding on mechanical properties of EPDM rubber testing samples

    Škrobák, Adam; STANĚK, Michal; Maňas, David; Ovsík, Martin; Šenkeřík, Vojtěch; Řezníček, Martin; Hýlova, Lenka


    The paper deals with the impact of the production process on mechanical properties (tensile strength and tear strength) of a standardized testing sample made of rubber compound based on ethylene propylene diene rubber produced by injection molding in comparison with a sample produced by classic preparation (cutting out a compression molded plate) according to the standard ISO 23529.

  9. Terpenoids from rhizomes of Alpinia japonica inhibiting nitric oxide production.

    Li, Qiang-Ming; Luo, Jian-Guang; Yang, Ming-Hua; Kong, Ling-Yi


    A new sesquiterpenoid, 1, and three new diterpenoids, 3-5, along with five known compounds, 2 and 6-9, were isolated from rhizomes of Alpinia japonica. The structures of the new compounds were determined as (1R,4R,6S,7S,9S)-4α-hydroxy-1,9-peroxybisabola-2,10-diene (1), methyl (12E)-16-oxolabda-8(17),12-dien-15-oate (3), (12R)-15-ethoxy-12-hydroxylabda-8(17),13(14)-dien-16,15-olide (4), and methyl (11E)-14,15,16-trinorlabda-8(17),11-dien-13-oate (5) by means of spectroscopic data. The absolute configurations at C(4) in 1 and C(12) in 4 were deduced from the circular dichroism (CD) data of the in situ-formed [Rh2 (CF3 COO)4 ] complexes. Inhibitory effects of the isolates on NO production in lipopolysaccharide-induced RAW264.7 macrophages were evaluated, and 2-4, 6, and 7 were found to exhibit inhibitory activities with IC50 values between 14.6 and 34.3 μM.

  10. Multistep Synthesis of a Terphenyl Derivative Showcasing the Diels-Alder Reaction

    Davie, Elizabeth A. Colby


    An adaptable multistep synthesis project designed for the culmination of a second-year organic chemistry laboratory course is described. The target compound is a terphenyl derivative that is an intermediate in the synthesis of compounds used in organic light-emitting devices. Students react a conjugated diene with dimethylacetylene dicarboxylate…

  11. A three-component synthesis of functionalized ketenimines by the reaction of alkyl isocyanides and dialkyl acetylenedicarboxylates in the presence of 2-quinolinol



    Full Text Available The 1:1 reactive intermediates generated by the addition of alkyl isocyanides to dialkyl acetylenedicarboxylates were trapped by 2-quinolinol to yield highly functionalized ketenimines and, in some cases, minor amounts of 1-azabuta-1,3-dienes.

  12. Copper-catalyzed oxidative alkynylation of diaryl imines with terminal alkynes: a facile synthesis of ynimines.

    Laouiti, Anouar; Rammah, Mohamed M; Rammah, Mohamed B; Marrot, Jérome; Couty, François; Evano, Gwilherm


    An efficient copper-mediated method for the oxidative alkynylation of diaryl imines with terminal alkynes is reported. This reaction provides the first catalytic and general synthesis of ynimines and allows for an easy preparation of these useful building blocks. An improved copper-catalyzed oxidative dimerization of imines to azines and the synthesis of dienes and azadienes from ynimines are also described.

  13. Structures and biological activities of triterpenes and sesquiterpenes obtained from Russula lepida.

    Lee, Jong-Soo; Maarisit, Wilmar; Abdjul, Delfly B; Yamazaki, Hiroyuki; Takahashi, Ohgi; Kirikoshi, Ryota; Kanno, Syu-Ichi; Namikoshi, Michio


    A seco-cucurbitane triterpene and two aristolane sesquiterpenes, named (24E)-3,4-seco-cucurbita-4,24-diene-3-hydroxy-26,29-dioic acid, (+)-1,2-didehydro-9-hydroxy-aristlone, and (+)-12-hydroxy-aristlone, were isolated from fruiting bodies of the medicinal mushroom Russula lepida, together with (24E)-3,4-seco-cucurbita-4,24-diene-3,26,29-trioic acid and (+)-aristlone. The structures of the first three compounds, including their absolute configurations, were assigned on the basis of their NMR and ECD spectra. Two seco-cucurbitane triterpenes, (24E)-3,4-seco-cucurbita-4,24-diene-3-hydroxy-26,29-dioic acid and (24E)-3,4-seco-cucurbita-4,24-diene-3,26,29-trioic acid, inhibited the activity of protein tyrosine phosphatase 1B (PTP1B), with IC50 values of 20.3 and 0.4μM, respectively. All isolated compounds did not show cytotoxicity against human cancer cell lines, Huh-7 (hepatoma) and EJ-1 (bladder), at 50μM. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. A New Diterpene from Suregada glomerulate(Blume) Baill

    Su Li HE; Ruo Yun CHEN


    A new diterpene with an abietane skeleton, 3β-hydroxy-8α, 14α-epoxyabieta-11,13(15)-dien-16,12-olide, was isolated from the root of Suregada glomerulate(Blume) Baill. Its structure was elucidated on the basis of spectroscopic and X-ray crystallographic analysis.

  15. An Abietane Diterpene and a Sterol from Fungus Phellinus igniarius


    A new abietane diterpene 12-hydroxy-7-oxo-5, 8, 11, 13-tetraene-18, 6-abietanolide,together with a new natural sterol stigmasta-7, 22-diene-3β, 5α, 6α-triol have been isolated from the fruiting body of the fungus Phellinus igniarius. Their structures were elucidated by spectroscopic methods including 2D NMR techniques.

  16. Chlorophytoside A, a New Labdane Diterpene Glycoside from Chlorophytum laxum

    You Heng GAO; Quan Xi MEI; Hui Fei WU; Yuan Ming DIAO; Xin Sheng PENG; Rui Fang ZHANG


    A new labdane-type diterpene glycoside 1 , chlorophytoside A, had been isolated from Chlorophytum laxum R.Br. The structure had been elucidated as (10S)-6α-hydroxylabda-8,13-dien-15,16-olide 3R-O-β-D-glucopyranoside on the basis of chemical and spectroscopic data.

  17. Lipid constituents of marine sponge Suberites carnosus

    Mishra, P.D.; Wahidullah, S.; DeSouza, L.; Kamat, S.Y.

    Sterols (22E) - 24- methyl-cholest - 4, 8(9), 22(23) - triene - 3, 7 - diol (1) and (22E)-24-methyl-ergost-6, 22(23)-diene-5, 8-epidioxy-3-ol (2), a fatty acid nonadecanoic acid and a fatty ester methyl nonadecanoate have been isolated from...

  18. SwissProt search result: AK104637 [KOME

    Full Text Available AK104637 006-310-D12 (Q9M6F0) Taxadien-5-alpha-ol O-acetyltransferase (EC (Taxa-4(20),11(12)-dien-5alpha-ol-O-acetyltransferase) (Taxadienol acetyltransferase) T5AT_TAXCU 2e-35 ...

  19. SwissProt search result: AK061211 [KOME

    Full Text Available AK061211 006-210-D05 (Q8S9G6) Taxadien-5-alpha-ol O-acetyltransferase (EC (Taxa-4(20),11(12)-dien-5alpha-ol-O-acetyltransferase) (Taxadienol acetyltransferase) T5AT_TAXCH 5e-46 ...

  20. SwissProt search result: AK065320 [KOME

    Full Text Available AK065320 J013002P13 (Q8S9G6) Taxadien-5-alpha-ol O-acetyltransferase (EC (Taxa-4(20),11(12)-dien-5alpha-ol-O-acetyltransferase) (Taxadienol acetyltransferase) T5AT_TAXCH 7e-30 ...

  1. UniProt search blastx result: AK288911 [KOME

    Full Text Available AK288911 J090081G18 Q8S9G6|T5AT_TAXCH Taxadien-5-alpha-ol O-acetyltransferase (EC 2....3.1.162) (Taxa-4(20),11(12)-dien-5alpha-ol-O-acetyltransferase) (Taxadienol acetyltransferase) - Taxus chinensis (Chinese yew) 1.00E-11 ...

  2. SwissProt search result: AK064755 [KOME

    Full Text Available AK064755 002-120-G03 (Q9M6F0) Taxadien-5-alpha-ol O-acetyltransferase (EC (Taxa-4(20),11(12)-dien-5alpha-ol-O-acetyltransferase) (Taxadienol acetyltransferase) T5AT_TAXCU 3e-26 ...

  3. SwissProt search result: AK099589 [KOME

    Full Text Available AK099589 J013043H09 (Q8S9G6) Taxadien-5-alpha-ol O-acetyltransferase (EC (Taxa-4(20),11(12)-dien-5alpha-ol-O-acetyltransferase) (Taxadienol acetyltransferase) T5AT_TAXCH 2e-22 ...

  4. Carbon-Oxygen Bond Cleavage by Bis(imino)pyridine Iron Compounds : Catalyst Deactivation Pathways and Observation of Acyl C-O Bond Cleavage in Esters

    Trovitch, Ryan J.; Lobkovsky, Emil; Bouwkamp, Marco W.; Chirik, Paul J.


    Investigations into the substrate scope of bis(imino)pyridine iron-catalyzed hydrogenation and [2 pi + 2 pi]. diene cyclization reactions identified C-O bond cleavage as a principal deactivation pathway. Addition of diallyl or allyl ethyl ether to the bis(imino)pyridine iron dinitrogen complex, ((iP

  5. 巨柏茎叶的萜类成分%Terpenoids from Stems and Leaves of Cupressus gigantea

    柳春梅; 周慧斌; 张卫东


    目的:对巨柏(Cupressus gigantea)茎叶的化学成分进行研究.方法:采用硅胶和Sephadex LH-20柱色谱的方法分离和纯化化合物,通过NMR,MS及理化性质鉴定化合物结构.结果:从巨柏茎叶分离得到15个labdane-type二萜,其中一个为新化合物,分别为:15-methoxy-18-hydroxylabda-8(17),13-diene(1),13-epitoruolsol(2),labd-8(17),14-dien-13-ol(3),13-epi-cupressic acid(4),cis-communic acid(5),trans-communic acid(6),labd-15-aceoxy-8(17),13E-dien(7),labd-8(17),13E-dien-15-ol(8),isocupressic acid(9),acetylisocupressic acid(10),isoabienol(11),13-oxo-14,15-dinor-labd-8(17)-en-19-oic acid(12),pimarenic acid(13),sandaracopimaric acid(14),and pimarol(15)此外还有两个已知倍半萜ent-oplopanone(16)和(+)-T-Cadinol(17).结论:化合物(1)为新的倍半萜,所有化合物均为首次从该植物中分得.

  6. D:C-friedooleanane-type triterpenoids from Lagenaria siceraria and their cytotoxic activity.

    Chen, Chiy-Rong; Chen, Hung-Wei; Chang, Chi-I


    Four new D:C-friedooleanane-type triterpenes, 3 beta-O-(E)-feruloyl-D:C-friedooleana-7,9(11)-dien-29-ol (1), 3 beta-O-(E)-coumaroyl-D:C-friedooleana-7,9(11)-dien-29-ol (2), 3 beta-O-(E)-coumaroyl-D:C-friedooleana-7,9(11)-dien-29-oic acid (3), and methyl 2 beta,3 beta-dihydroxy-D:C-friedoolean-8-en-29-oate (6), together with five known triterpenes with the same skeleton, 3-epikarounidiol (4), 3-oxo-D:C-friedoolena-7,9(11)-dien-29-oic acid (5), bryonolol (7), bryononic acid (8), and 20-epibryonolic acid (9), were isolated from the methanol extract of the stems of Lagenaria siceraria. The structures of those compounds were elucidated using spectroscopic methods. Compounds 3 and 9 showed significant cytotoxic activity against the SK-Hep 1 cell line with IC50 values of 4.8 and 2.1 microg/ml, respectively. Based on these initially promising results, the two D:C-friedooleanane triterpenes merit further study as potential anticancer agents.

  7. [Antioxidant and cardioprotective effects of N-tyrosol in myocardial ischemia with reperfusion in rats].

    Smol'iakova, V I; Chernyshova, G A; Plotnikov, M B; Aliev, O I; Krasnov, E A


    We demonstrated in experiments on rats with left coronary artery occlusion that intravenous administration of 20 mg/kg n-tyrosol during ischemia limited manifestations of oxidative stress in myocardial tissue during early post reperfusion period: content of diene and triene conjugates lowered 16 and 20%, respectively. This was associated with higher preservation of cardiomyocytes and reduction of the infarction zone.

  8. Defense Infrastructure: In-Kind Construction and Renovation Projects Initiated by DOD during Fiscal Year 2013


    with an Ethylene Propylene Diene Monomer roof system with rigid insulation Service review and approval letter of contractor cost estimate...air conditioning, fire protection, utility connections, pavement , and information systems. Agreement between Army and Air Force Exchange Services...existing roof systems of buildings 373 and 167 with a synthetic rubber roof system with rigid insulation Alliant Techsystems Lease Agreement

  9. Benzofurans as efficient dienophiles in normal electron demand [4 + 2] cycloadditions.

    Chopin, Nathalie; Gérard, Hélène; Chataigner, Isabelle; Piettre, Serge R


    Dearomatization of electron-poor benzofurans is possible through involvement of the aromatic 2,3-carbon-carbon double bond as dienophile in normal electron demand [4 + 2] cycloadditions. The tricyclic heterocycles thereby produced bear a quaternary center at the cis ring junction, a feature of many alkaloids such as morphine, galanthamine, or lunaridine. The products arising from the reaction have been shown to depend on different factors among which the type of the electron-withdrawing substituent of the benzofuran, the nature of the reacting diene, and the method of activation. In the presence of all-carbon dienes, the reaction yields the expected Diels-Alder adducts. When thermal activation is insufficient, a biactivation associating zinc chloride catalysis and high pressure is required to generate the cycloadducts in good yields and high stereoselectivities, for instance, when cyclohexadiene is involved in the process. The use of more functionalized dienes, such as those bearing alkoxy or silyloxy substituents, also shows the limits of the thermal activation, and hyperbaric conditions are, in this case, well-suited. The involvement of Danishefsky's diene induces a competition in the site of reactivity. The aromatic 2,3-carbon-carbon double bond is unambiguously the most reactive dienophile, and the 3-carbonyl unit becomes a competitive site of reactivity with benzofurans bearing substituents prone to heterocyloaddition, in particular under Lewis acid activation. The sequential involvement of both the aromatic double bond and the carbonyl moiety as dienophiles is then possible by using an excess of diene under high-pressure activation. In line with the experimental results, DFT computations suggest that the Diels-Alder process involving the aromatic double bond is preferred over the hetero-Diels-Alder route through an asynchronous concerted transition state. However, Lewis acid catalysis appears to favor the heterocycloaddition pathway through a stepwise

  10. Highly Regio- and Stereoselective Diels-Alder Cycloadditions via Two-Step and Multicomponent Reactions Promoted by Infrared Irradiation under Solvent-Free Conditions

    Francisco Delgado


    Full Text Available Infrared irradiation promoted the Diels-Alder cycloadditions of exo-2-oxazolidinone dienes 1–3 with the Knoevenagel adducts 4–6, as dienophiles, leading to the synthesis of new 3,5-diphenyltetrahydrobenzo[d]oxazol-2-one derivatives (7, 9, 11 and 13–17, under solvent-free conditions. These cycloadditions were performed with good regio- and stereoselectivity, favoring the para-endo cycloadducts. We also evaluated the one-pot three-component reaction of active methylene compounds 20, benzaldehydes 21 and exo-2-oxazolidinone diene 2 under the same reaction conditions. A cascade Knoevenagel condensation/Diels-Alder cycloaddition reaction was observed, resulting in the final adducts 13–16 in similar yields. These procedures are environmentally benign, because no solvent and no catalyst were employed in these processes. The regioselectivity of these reactions was rationalized by Frontier Molecular Orbital (FMO calculations.

  11. Intense and exhaustive exercise induce oxidative stress in skeletal muscle

    T Thirumalai


    Full Text Available Objective: To assess the oxidative stress and antioxidant defense system in the skeletal muscle of male albino rats subjected to strenuous exercise programme. Methods: Wistar strain albino rats were subjected to exhaustive swimming exercise programme daily for a period of five days. The thiobarbituric acid reactive substances (TBARS, conjugated dienes, superoxide dismutase, catalase, glutathione peroxidase and glutathione-S-transferase were measured in the gastrocnemius muscle of the exercised animals. Results: The elevated levels of TBARS and conjugated dienes indicated the oxidative stress in the gastrocemius muscle of the exercised animals. The depleted activity levels of superoxide dismutase, catalase, glutathione peroxidase and glutathione-S-transferase in the exercise animals indicated the increased oxidative stress and decreased antioxidative defense system in the muscle. Conclusions: The study suggests that prolonged strenuous exercise programme can induce oxidative stress and therefore an optimal level of exercise schedule should be advocated to obtain the maximum benefit of exercise programme.

  12. A kinetic model for the first stage of pygas upgrading

    J. L. de Medeiros


    Full Text Available Pyrolysis gasoline - PYGAS - is an intermediate boiling product of naphtha steam cracking with a high octane number and high aromatic/unsaturated contents. Due to stabilization concerns, PYGAS must be hydrotreated in two stages. The first stage uses a mild trickle-bed conversion for removing extremely reactive species (styrene, dienes and olefins prior to the more severe second stage where sulfured and remaining olefins are hydrogenated in gas phase. This work addresses the reaction network and two-phase kinetic model for the first stage of PYGAS upgrading. Nonlinear estimation was used for model tuning with kinetic data obtained in bench-scale trickle-bed hydrogenation with a commercial Pd/Al2O3 catalyst. On-line sampling experiments were designed to study the influence of variables - temperature and spatial velocity - on the conversion of styrene, dienes and olefins.

  13. Sex-pairing pheromone in the Asian termite pest species Odontotermes formosanus.

    Wen, Ping; Ji, Bao-Zhong; Liu, Shu-Wen; Liu, Cong; Sillam-Dussès, David


    The sex-pairing pheromone of the black winged subterranean termite, Odontotermes formosanus (Shiraki) (Isoptera, Termitidae), was investigated using headspace-SPME, GC-MS, GC-EAD, and attraction bioassays. Females secrete the pheromone from their sternal gland to attract males. The sex-pairing pheromone is composed of (Z,Z)-dodeca-3,6-dien-1-ol and (Z)-dodec-3-en-1-ol, estimated at 9 to 16.64 ng and 0.2 to 0.54 ng, respectively. Both short- and long-distance sex attraction bioassays were employed to show that these compounds act in synergy at long distance, but only (Z,Z)-dodeca-3,6-dien-1-ol is active at short distance. The pheromone may be useful in efforts to control this pest, which is considered one of the most harmful termite species in Southeast Asia.

  14. Bisabocurcumin, a new skeleton curcuminoid from the rhizomes of Curcuma longa L.

    Yun Chuan Xiao; Jing Xie; Min Yu; Miao Liu; Jian Ran; Zhen Xi; Wei Li; Jing Huang


    A new skeleton bisabolane-type sesquiterpene curcuminoid, bisabocurcumin (1), along with 5 known compounds, curcumin (2), demethoxycurcumin (3), bidemethoxycurcumin (4), (1E,4E)-l,5-bis(4-hydroxy-3-methoxyphenyl)-penta-1,4-dien-3-one (5), and (1E,4E)-1-(4-hydroxy-3-methoxyphenyl)-5-(4-hydroxy phenyl-)-penta-1,4-dien-3-one (6) were isolated from the rhizomes of Curcuma longa L. Their structures were determined on the basis of spectroscopic analysis. Bisabocurcumin (1) is firstly obtained from nature with a new skeleton combined by a bisabolane-type sesquiterpene and a 1,7-diphenylheptanoid through a C-C bond.

  15. Biotransformation of a cage-like diels-alder adduct and derivatives by Mucor ramosissimus samutsevitsch Biotransformação de um aduto de diels-alder cage-like e derivados por Mucor ramosissimus samutsevitsch

    Felicia Megumi Ito


    Full Text Available The present study aimed to evaluate the ability for biotransformation of the Diels-Alder adduct tricyclo[,7]undeca-4,9-dien-3,6-dione (1 and two synthetic derivatives by the saprobe fungus Mucor ramosissimus Samutsevitsch. Products from oxidation, isomerization and, regioselective and enantioselective reduction were achieved.Neste trabalho avaliou-se a capacidade de biotransformação do aduto de Diels-Alder triciclo[]undeca-4,9-dien-3,6-diona (1 e dois derivados sintéticos pelo fungo sapróbio Mucor ramosissimus Samutsevitsch. Produtos de oxidação, isomerização e redução regiosseletiva e enantiosseletiva foram obtidos.

  16. EFSA CEF Panel (EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids), 2015. Scientific Opinion on Flavouring Group Evaluation 208 Revision 1 (FGE.208Rev1): Consideration of genotoxicity data on representatives for 10 alicyclic aldehydes with the a,b-unsaturation in ring / side-chain and precursors from chemical subgroup 2.2 of FGE.19

    Beltoft, Vibe Meister; Nørby, Karin Kristiane

    genotoxicity studies on p-mentha-1,8-dien-7-al [FL-no: 05.117], the representative substance for FGE.19 subgroup 2.2. This substance was tested in vivo in a combined micronucleus assay in bone marrow and Comet assay in liver and duodenum. It did not induce any increase in micronucleated polychromatic...... erythrocytes of the bone marrow of male rats in the micronucleus test and it did not induce DNA damage in duodenum of the same animals as analysed by the Comet assay. The Comet assay performed in liver shows a positive result and therefore the Panel concluded that p-mentha-1,8-dien-7-al [FL-no: 05...

  17. Terpenoids, flavonoids and other constituents of Eupatorium betonicaeforme (Asteraceae)

    Albuquerque, Maria Rose Jane R.; Pires, Andreza Maria L.; Pessoa, Otilia Deusdenia L.; Silveira, Edilberto R. [Ceara Univ., Fortaleza, CE (Brazil). Dept. de Quimica Organica e Inorganica. Curso de Pos-Graduacao em Quimica Organica]. E-mail:


    A new acylated kaurene diterpene, characterized as 15{alpha}-decanoyloxy-kaur-16-en-19-oic acid, along with nine known compounds: pentacosanoic acid, 24{alpha}-ethyl-5{alpha}-cholesta-7,22E-dien-3{beta}-ol, 15{alpha}-hydroxy-kaur-16-en-19-oic acid, 8{beta}-angeloyloxy-9{beta},10{beta}-dihydroxy-1-oxogermacra-4E,11(13)dien-12,6{alpha}-olide, 3{beta}-hydroxyeicosan-1,5{beta}-olide, taraxasteryl acetate, 7-Omethylkaempferol, kaempferol, and nepetin were isolated from the flowers of Eupatorium betonicaeforme (Asteraceae). In addition, from the aerial parts were isolated taraxasteryl acetate and {alpha}- and {beta}-amyrin, while the mixture of {beta}-sitosterol and stigmasterol, and 6-acetyl-2,2-dimethylchroman-4-one were isolated from the roots. The structure elucidation of all compounds was performed by spectroscopic analysis and comparison with published data from literature. (author)

  18. Essential-oil polymorphism in the 'resurrection plant' Myrothamnus moschatus and associated ethnobotanical knowledge.

    Randrianarivo, Emmanuel; Rasoanaivo, Philippe; Nicoletti, Marcello; Razafimahefa, Solofoniaina; Lefebvre, Manon; Papa, Fabrizio; Vittori, Sauro; Maggi, Filippo


    Gas chromatography/mass spectroscopy analysis (GC/MS) of essential oils obtained from populations of the resurrection plant Myrothamnus moschatus, growing in different areas of Madagascar, allowed identification of three main chemotypes in the species. The first one was provided by plants with a high content of trans-pinocarveol and pinocarvone; the second one involved plants with high percentages of limonene, cis- and trans-p-mentha-1(7),8-dien-2-ol, and β-selinene; and the third chemotype was characterized by plants with high levels of oxygenated sesquiterpenes such as caryophyllene oxide and α- and β-isomers of caryophylla-4(12),8(13)-dien-5-ol. Chemical data were supported by chemometric technique as the principal component analysis. Furthermore, the relationship between the dioecy and phytochemistry within one population was also considered. Finally, correlations between chemical variations and ethnobotanical data were assessed. Copyright © 2013 Verlag Helvetica Chimica Acta AG, Zürich.

  19. Antioxidant and antifungal activities of Camellia sinensis (L. Kuntze leaves obtained by different forms of production

    L. E. A. Camargo

    Full Text Available Abstract The antioxidant and anticandidal activities of leaves obtained from Camellia sinensis by non-fermentation (green and white teas, semi-fermentation (red tea and fermentation method (black tea were investigated. It was evaluated the total phenolic content by Folin-Ciocalteau assay; antioxidant capacities were evaluated in vitro using DPPH and ABTS radicals, hypochlorous acid and superoxide anion scavenger assays, induced hemolysis, lipid peroxidation by conjugated diene formation and myeloperoxidase activity. Anticandidal activity was performed on three strains of Candida spp. The results showed that non-fermented teas have a higher concentration of phenolic compounds, and then presented the best inhibitory activity of AAPH-induced hemolysis, the best inhibition of conjugated diene formation and more pronounced antioxidant activity in all tests. The highest anticandidal activity was obtained from fermented tea, followed by non-fermented tea. These results indicate that the antioxidant activity demonstrated has no direct relation with the anticandidal activity.

  20. Ion chemistry for the detection of isoprene and other volatile organic compounds in ambient air

    Leibrock, Edeltraud; Huey, L. Gregory


    A chemical ionization mass spectrometer (CIMS) and a flowing afterglow apparatus were used to study reactions of benzene cations (C6H6+ and (C6H6)2+) with a series of volatile organic compounds (VOCs). Both cations react at the collision rate with compounds of lower ionization potential than benzene, such as isoprene (C5H8), other conjugated dienes, and aromatics. These ions are generally unreactive with substances of higher ionization potential such as alkanes, simple alcohols, simple carbonyls, etc. The results demonstrate that C6H6+ and (C6H6)2+ are excellent reagent ions for the sensitive detection of isoprene in air with a CIMS. However, 2-methyl-3-buten-2-ol (MBO) and C5H8 conjugated dienes were identified as potential interferences to this technique. This indicates that the selectivity of the CIMS isoprene measurement must be tested by intercomparison with well-established methods, e.g. gas chromatography techniques.