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Sample records for amination

  1. amines

    Directory of Open Access Journals (Sweden)

    Styszko Katarzyna

    2017-01-01

    Full Text Available The study investigated the application of char activated with CO2 and impregnated with amines solutions for removal of selected xenobiotics from aqueous solutions. The chars produced from the pyrolysis of waste tires. The solutions of monoethanolamine (MEA, diethanolamine (DEA and polyethylenimine (PEI were used for impregnation of char. The sorption capacity of char impregnated with amines depended on amines chemical properties. The adsorptive removal of mixture of pharmaceuticals residues by modified materials was assessed. BET surface area of materials varied from 36 m2 g−1 to 128 m2 g−1. The highest removal efficiencies up to 99 % were observed for char impregnated with PEI.

  2. Amine Functionalized Porous Network

    KAUST Repository

    Eddaoudi, Mohamed

    2015-05-28

    Amine groups can be introduced in porous materials by a direct (one pot) or post-synthetic modification (PSM) process on aldehyde groups, and the resulting porous materials have increased gas affinity.

  3. Biogenic amines in beer

    OpenAIRE

    Čiháková, Dagmar

    2016-01-01

    This thesis deals with the technological process of brewing beer, describes the raw materials needed for its production, and points out the useful and harmful substances contained in beer as biogenic amines (BA). Furthermore, there are described the issues of biogenic amines in food and primarily in beer, which is a histamine, putrescine, cadaverine, tyramine and tryptamine. In the practical section BA was determined in lager bottom-fermented beers from local microbreweries and large industri...

  4. High capacity immobilized amine sorbents

    Science.gov (United States)

    Gray, McMahan L.; Champagne, Kenneth J.; Soong, Yee; Filburn, Thomas

    2007-10-30

    A method is provided for making low-cost CO.sub.2 sorbents that can be used in large-scale gas-solid processes. The improved method entails treating an amine to increase the number of secondary amine groups and impregnating the amine in a porous solid support. The method increases the CO.sub.2 capture capacity and decreases the cost of utilizing an amine-enriched solid sorbent in CO.sub.2 capture systems.

  5. CHITOSE AMINE & BODY ACUPOINTS' COSMETOLOGY

    Institute of Scientific and Technical Information of China (English)

    TEO Gek Chun

    2002-01-01

    @@ Chitose Amine is a natural substance which the body cells will readily absorb and it helps strengthen the immune system and reduces the cholesterol. Currently. Chitose Amine has been used widely in cosmetics and detoxification foods. The mian therapeutic properties of Chitose Amine in cosmetics are as follow:

  6. Hydrothermal Reactivity of Amines

    Science.gov (United States)

    Robinson, K.; Shock, E.; Hartnett, H. E.; Williams, L. B.; Gould, I.

    2013-12-01

    The reactivity of aqueous amines depends on temperature, pH, and redox state [1], all of which are highly variable in hydrothermal systems. Temperature and pH affect the ratio of protonated to unprotonated amines (R-NH2 + H+ = R-NH3+), which act as nucleophiles and electrophiles, respectively. We hypothesize that this dual nature can explain the pH dependence of reaction rates, and predict that rates will approach a maximum at pH = pKa where the ratio of protonated and unprotonated amines approaches one and the two compounds are poised to react with one another. Higher temperatures in hydrothermal systems allow for more rapid reaction rates, readily reversible reactions, and unique carbon-nitrogen chemistry in which water acts as a reagent in addition to being the solvent. In this study, aqueous benzylamine was used as a model compound to explore the reaction mechanisms, kinetics, and equilibria of amines under hydrothermal conditions. Experiments were carried out in anoxic silica glass tubes at 250°C (Psat) using phosphate-buffered solutions to observe changes in reaction rates and product distributions as a function of pH. The rate of decomposition of benzylamine was much faster at pH 4 than at pH 9, consistent with the prediction that benzylamine acts as both nucleophile and an electrophile, and our estimate that the pKa of benzylamine is ~5 at 250°C and Psat. Accordingly, dibenzylamine is the primary product of the reaction of two benzylamine molecules, and this reaction is readily reversible under hydrothermal conditions. Extremely acidic or basic pH can be used to suppress dibenzylamine production, which also suppresses the formation of all other major products, including toluene, benzyl alcohol, dibenzylimine, and tribenzylamine. This suggests that dibenzylamine is the lone primary product that then itself reacts as a precursor to produce the above compounds. Analog experiments performed with ring-substituted benzylamine derivatives and chiral

  7. Amine-Amine Exchange in Aminium-Methanesulfonate Aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Dawson, Matthew L.; Varner, Mychel E.; Perraud, Veronique M.; Ezell, Michael J.; Wilson, Jacqueline M.; Zelenyuk, Alla; Gerber, Robert B.; Finlayson-Pitts, Barbara J.

    2014-12-18

    Aerosol particles are ubiquitous in the atmosphere and have been shown to impact the Earth’s climate, reduce visibility, and adversely affect human health. Modeling the evolution of aerosol systems requires an understanding of the species and mechanisms involved in particle growth, including the complex interactions between particle- and gas-phase species. Here we report studies of displacement of amines (methylamine, dimethylamine or trimethylamine) in methanesulfonate salt particles by exposure to a different gas-phase amine, using a single particle mass spectrometer, SPLAT II. The variation of the displacement with the nature of the amine suggests that behavior is dependent on water in or on the particles. Small clusters of methanesulfonic acid with amines are used as a model in quantum chemical calculations to identify key structural elements that are expected to influence water uptake, and hence the efficiency of displacement by gas-phase molecules in the aminium salts. Such molecular-level understanding of the processes affecting the ability of gas-phase amines to displace particle-phase aminium species is important for modeling the growth of particles and their impacts in the atmosphere.

  8. Amine Swingbed Payload Project Management

    Science.gov (United States)

    Walsch, Mary; Curley, Su

    2013-01-01

    The International Space Station (ISS) has been designed as a laboratory for demonstrating technologies in a microgravity environment, benefitting exploration programs by reducing the overall risk of implementing such technologies in new spacecraft. At the beginning of fiscal year 2010, the ISS program manager requested that the amine-based, pressure-swing carbon dioxide and humidity absorption technology (designed by Hamilton Sundstrand, baselined for the Orion Multi-Purpose Crew Vehicle, and tested at the Johnson Space Center in relevant environments, including with humans, since 2005) be developed into a payload for ISS Utilization. In addition to evaluating the amine technology in a flight environment before the first launch of the Orion vehicle, the ISS program wanted to determine the capability of the amine technology to remove carbon dioxide from the ISS cabin environment at the metabolic rate of the full 6 ]person crew. Because the amine technology vents the absorbed carbon dioxide and water vapor to space vacuum (open loop), additional hardware needed to be developed to minimize the amount of air and water resources lost overboard. Additionally, the payload system would be launched on two separate Space Shuttle flights, with the heart of the payload-the swingbed unit itself-launching a full year before the remainder of the payload. This paper discusses the project management and challenges of developing the amine swingbed payload in order to accomplish the technology objectives of both the open -loop Orion application as well as the closed-loop ISS application.

  9. Amine Swingbed Payload Technology Demonstration

    Science.gov (United States)

    Sweterlitsch, Jeffrey

    2014-01-01

    The Amine Swingbed is an amine-based, vacuum-regenerated adsorption technology for removing carbon dioxide and humidity from a habitable spacecraft environment, and is the baseline technology for the Orion Program’s Multi-Purpose Crew Vehicle (MPCV). It uses a pair of interleaved-layer beds filled with SA9T, the amine sorbent, and a linear multiball valve rotates 270° back and forth to control the flow of air and vacuum to adsorbing and desorbing beds. One bed adsorbs CO2 and H2O from cabin air while the other bed is exposed to vacuum for regeneration by venting the CO2 and H2O. The two beds are thermally linked, so no additional heating or cooling is required. The technology can be applied to habitable environments where recycling CO2 and H2O is not required such as short duration missions.

  10. Complex amine-based reagents

    Science.gov (United States)

    Suslov, S. Yu.; Kirilina, A. V.; Sergeev, I. A.; Zezyulya, T. V.; Sokolova, E. A.; Eremina, E. V.; Timofeev, N. V.

    2017-03-01

    Amines for a long time have been applied to maintaining water chemistry conditions (WCC) at power plants. However, making use of complex reagents that are the mixture of neutralizing and the filmforming amines, which may also contain other organic components, causes many disputes. This is mainly due to lack of reliable information about these components. The protective properties of any amine with regard to metal surfaces depend on several factors, which are considered in this article. The results of applying complex reagents to the protection of heating surfaces in industrial conditions and estimated behavior forecasts for various reagents under maintaining WCC on heat-recovery boilers with different thermal circuits are presented. The case of a two-drum heat-recovery boiler with in-line drums was used as an example, for which we present the calculated pH values for various brands of reagents under the same conditions. Work with different reagent brands and its analysis enabled us to derive a composition best suitable for the conditions of their practical applications in heat-recovery boilers at different pressures. Testing the new amine reagent performed at a CCPP power unit shows that this reagent is an adequate base for further development of reagents based on amine compounds. An example of testing a complex reagent is shown created with the participation of the authors within the framework the program of import substitution and its possible use is demonstrated for maintaining WCC of power-generating units of combined-cycle power plants (CCPP) and TPP. The compliance of the employed reagents with the standards of water chemistry conditions and protection of heating surfaces were assessed. The application of amine-containing reagents at power-generating units of TPP makes it possible to solve complex problems aimed at ensuring the sparing cleaning of heating surfaces from deposits and the implementation of conservation and management of water chemistry condition

  11. Bacterial degradation of monocyclic aromatic amines

    Directory of Open Access Journals (Sweden)

    Pankaj Kumar Arora

    2015-08-01

    Full Text Available Aromatic amines are an important group of industrial chemicals, which are widely used for manufacturing of dyes, pesticides, drugs, pigments, and other industrial products. These compounds have been considered highly toxic to human beings due to their carcinogenic nature. Three groups of aromatic amines have been recognized: monocyclic, polycyclic and heterocyclic aromatic amines. Bacterial degradation of several monocyclic aromatic compounds has been studied in a variety of bacteria, which utilizes monocyclic aromatic amines as their sole source of carbon and energy. Several degradation pathways have been proposed and the related enzymes and genes have also been characterized. Many reviews have been reviewed toxicity of monocyclic aromatic amines; however, there is lack of review on biodegradation of monocyclic aromatic amines. The aim of this review is to summarize bacterial degradation of monocyclic aromatic amines. This review will increase our current understanding of biochemical and molecular basis of bacterial degradation of monocyclic aromatic amines.

  12. Polymeric amines and biomedical uses thereof

    NARCIS (Netherlands)

    Broekhuis, Antonius; Zhang, Youchum; Picchioni, Francesco; Roks, Antonius

    2010-01-01

    The invention relates to the field of polymers and biomedical applications thereof. In particular, it relates to the use of polymeric amines derived from alternating polyketones.Provided is the use of a polymeric amine for modulating or supporting cellular behavior, said polymeric amine being an alt

  13. Advances in heterocyclic ketene aminals

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Recent developments in the study of the reactions of heterocyclic ketene aminals are reviewed with the emphases on regioselective alkylation, acylation and glycosylation reactions, and on the aza-ene reactions with α,β-unsaturated compounds, azo and carbonyl compounds. Reactions with 1,3-dipoles and other reagents to synthesize fused heterocycles are also discussed.

  14. Aminering van hydroxyderivaten van halogeenazahetarenen

    NARCIS (Netherlands)

    Roelfsema, W.A.

    1972-01-01

    In this thesis an introductory investigation is described on the reactivity of hydroxy derivatives of halogenopyridines and a bromohydroxyquinoline towards strong bases.It is a sequel to earlier work on the effect of substituents present in the nucleus of halogenopyridines on the course of amination

  15. Biogenic amines in fermented foods

    NARCIS (Netherlands)

    Spano, G.; Russo, P.; Lonvaud-Funel, A.; Lucas, P.; Alexandre, H.; Grandvalet, C.; Coton, E.; Coton, M.; Barnavon, L.; Bach, B.; Rattray, F.; Bunte, A.; Magni, C.; Ladero, V.; Alvarez, M.; Fernández, M.; Lopez, P.; Palencia, P.F. de; Corbi, A.; Trip, H.; Lolkema, J.S.

    2010-01-01

    Food-fermenting lactic acid bacteria (LAB) are generally considered to be non-toxic and non-pathogenic. Some species of LAB, however, can produce biogenic amines (BAs). BAs are organic, basic, nitrogenous compounds, mainly formed through decarboxylation of amino acids. BAs are present in a wide rang

  16. Trace Amines and the Trace Amine-Associated Receptor 1: Pharmacology, Neurochemistry, and Clinical Implications

    OpenAIRE

    Yue ePei; Aman eAsif-Malik; Canales, Juan J.

    2016-01-01

    Biogenic amines are a collection of endogenous molecules that play pivotal roles as neurotransmitters and hormones. In addition to the “classical” biogenic amines resulting from decarboxylation of aromatic acids, including dopamine (DA), norepinephrine, epinephrine, serotonin (5-HT), and histamine, other biogenic amines, present at much lower concentrations in the central nervous system (CNS), and hence referred to as “trace” amines (TAs), are now recognized to play significant neurophysiolog...

  17. Flotation of kaolinite with dodecyl tertiary amines

    Institute of Scientific and Technical Information of China (English)

    CAO Xue-feng; LIU Chang-miao; HU Yue-hua

    2009-01-01

    The flotation of kaolinite using a series of tertiary amines (N,N-dimethyl-dodecyl amine (DRN), N,N-diethyl-dodecyl amine (DEN), N,N-dipropyl-dodecyl amine (DPN) and N,N-dibenzyl-bodecyi amine (DBN)) was investigated. The results show that the maximum recoveries of kaolinite for DEN, DPN and DRN are 93%, 88% and 84%, respectively, but that of DBN is very low. On the basis of zeta potential and FT-IR spectra, the ionization of surface hydroxyl and isomorphic exchange of surface ions account for the charging mechanisms of kaolinite surface. The adsorption mechanism of tertiary amines on kaolinite surface is mainly electrostatic. The isoelectric point (IEP) of kaolinite increases from 3.4 to some more positive points after the interaction of kaolinite with the four tertiary amines. The FT-IR spectra of kaolinite change with the presence of some new sharp shapes belonging to the tertiary amines. The inductive electronic effects and space-steric effects of -CH_3, -C_2H_5, -C_3H_7 and -C_7H_7 bonding to N atom result in different collecting power of the four tertiary amines.

  18. Intolerance to dietary biogenic amines: A review

    NARCIS (Netherlands)

    Jansen, S.C.; Dusseldorp, M. van; Bottema, K.C.; Dubois, A.E.J.

    2003-01-01

    Objective: To evaluate the scientific evidence for purported intolerance to dietary biogenic amines. Data Sources: MEDLINE was searched for articles in the English language published between January 1966 and August 2001. The keyword biogenic amin* was combined with hypersens*, allerg*, intoler*, and

  19. Palladium-catalyzed amination of allyl alcohols.

    Science.gov (United States)

    Ghosh, Raju; Sarkar, Amitabha

    2011-10-21

    An efficient catalytic amination of aryl-substituted allylic alcohols has been developed. The complex [(η(3)-allyl)PdCl](2) modified by a bis phosphine ligand, L, has been used as catalyst in the reaction that afforded a wide range of allyl amines in good to excellent yield under mild conditions.

  20. Speaking Personally--with Amin Qazi

    Science.gov (United States)

    Ragan, Lawrence

    2016-01-01

    This article provides an interview with Amin Quazi, the founding chief executive officer of Unizin, a university-owned consortium focused on the emerging digital teaching and learning ecosystem. Amin has a bachelor's degree in chemical engineering from The University of Iowa and a master's degree in business administration from the Carlson School…

  1. Method for the production of primary amines

    NARCIS (Netherlands)

    Baldenius, Kai-Uwe; Ditrich, Klaus; Breurer, Michael; Navickas, Vaidotas; Janssen, Dick; Crismaru, Ciprian; Bartsch, Sebastian

    2014-01-01

    The present invention relates to a novel enzymatically catalyzed method for the production of aliphatic primary amines, which method comprises the enzymatic oxidation of a primary aliphatic alcohol catalyzed by an alcohol dehydrogenase, amination of the resulting oxocompound catalyzed by a transamin

  2. Intolerance to dietary biogenic amines : a review

    NARCIS (Netherlands)

    Jansen, SC; van Dusseldorp, M; Bottema, KC; Dubois, AEJ

    2003-01-01

    Objective: To evaluate the scientific evidence for purported intolerance to dietary biogenic amines. Data Sources: MEDLINE was searched for articles in the English language published between January 1966 and August 2001. The keyword biogenic amin* was combined with hypersens*, allergen intoler*, and

  3. Thermodynamics of mixtures containing amines

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, Juan Antonio [G.E.T.E.F. Dpto Termodinamica y Fisica Aplicada, Facultad de Ciencias, Universidad de Valladolid, Valladolid 47071 (Spain)], E-mail: jagl@termo.uva.es; Mozo, Ismael; Garcia de la Fuente, Isaias; Cobos, Jose Carlos [G.E.T.E.F. Dpto Termodinamica y Fisica Aplicada, Facultad de Ciencias, Universidad de Valladolid, Valladolid 47071 (Spain); Riesco, Nicolas [Department of Chemical Engineering, Loughborough University, Loughborough, LE113TU Leicestershire (United Kingdom)

    2008-01-30

    Mixtures with dimethyl or trimethylpyridines and alkane, aromatic compound or 1-alkanol have been examined using different theories: DISQUAC, Flory, the concentration-concentration structure factor, S{sub CC}(0), or the Kirkwood-Buff formalism. DISQUAC represents fairly well the available experimental data, and improves theoretical calculations from Dortmund UNIFAC. Two important effects have been investigated: (i) the effect of increasing the number of methyl groups attached to the aromatic ring of the amine; (ii) the effect of modifying the position of the methyl groups in this ring. The molar excess enthalpy, H{sup E}, and the molar excess volume, V{sup E}, decrease in systems with alkane or methanol as follows: pyridine > 3-methylpyridine > 3,5-dimethylpyridine and pyridine > 2-methylpyridine > 2,4-dimethylpyridine > 2,4,6-trimethylpyridine, which has been attributed to a weakening of the amine-amine interactions in the same sequences. This is in agreement with the relative variation of the effective dipole moment, {mu}-bar, and of the differences between the boiling temperature of a pyridine base and that of the homomorphic alkane. For heptane solutions, the observed H{sup E} variation, H{sup E} (3,5-dimethylpyridine) > H{sup E} (2,4-dimethylpyridine) > H{sup E} (2,6-dimethylpyridine), is explained similarly. Calculations on the basis of the Flory model confirm that orientational effects become weaker in systems with alkane in the order: pyridine > methylpyridine > dimethylpyridine > trimethylpyridine. S{sub CC}(0) calculations show that steric effects increase with the number of CH{sub 3}- groups in the pyridine base, and that the steric effects exerted by methyl groups in positions 2 and 6 are higher than when they are placed in positions 3 and 5. The hydrogen bond energy in methanol mixtures is independent of the pyridine base, and it is estimated to be -35.2 kJ mol{sup -1}. Heterocoordination in these solutions is due in part to size effects. Their

  4. Quantifying amine permeation sources with acid neutralization: calibrations and amines measured in coastal and continental atmospheres

    Directory of Open Access Journals (Sweden)

    N. A. Freshour

    2014-04-01

    Full Text Available An acid titration method for quantifying amine permeation rates was used to calibrate an Ambient pressure Proton transfer Mass Spectrometer (AmPMS that monitors ambient amine compounds. The method involves capturing amines entrained in a N2 flow by bubbling it through an acidified solution (~ 10−5 M HCl, and the amines are quantified via changes in solution pH with time. Home-made permeation tubes had permeation rates (typically tens of pmol s−1 that depended on the type of amine and tubing and on temperature. Calibrations of AmPMS yielded sensitivities for ammonia, methyl amine, dimethyl amine, and trimethyl amine that are close to the sensitivity assuming a gas-kinetic, ion-molecule rate coefficient. The permeation tubes were also designed to deliver a reproducible amount of amine to a flow reactor where nucleation with sulfuric acid was studied. The high proton affinity compound dimethyl sulfoxide (DMSO, linked to oceanic environments, was also studied and AmPMS is highly sensitive to it. AmPMS was deployed recently in two field campaigns and mixing ratios are reported for ammonia, alkyl amines, and DMSO and correlations between these species and with particle formation events are discussed.

  5. Interaction energies of CO2·amine complexes: effects of amine substituents.

    Science.gov (United States)

    Jorgensen, Kameron R; Cundari, Thomas R; Wilson, Angela K

    2012-10-25

    To focus on the identification of potential alternative amine carbon capture compounds, CO(2) with methyl, silyl, and trifluoromethyl monosubstituted and disubstituted amine compounds were studied. Interaction energies of these CO(2)·amine complexes were determined via two methods: (a) an ab initio composite method, the correlation consistent composite approach (ccCA), to determine interaction energies and (b) density functional theories, B3LYP/aug-cc-pVTZ and B97D/aug-cc-pVTZ. Substituent effects on the interaction energies were examined by interchanging electron donating and electron withdrawing substituents on the amine compounds. The calculations suggested two different binding modes, hydrogen bonding and acid-base interactions, which arise from the modification of the amine substituents, echoing previous work by our group on modeling protein·CO(2) interactions. Recommendations have been noted for the development of improved amine scrubber complexes.

  6. Advance in the synthesis of aromatic amine via direct amination

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Arylamines are very common and important organic molecules. Acting as important intermediates in medical and chemical industry, they are widely used in the synthesis of pharmaceuticals, dyes, pesticides, rubber additives, isocyanates and heterocyclic compounds. The traditional methods for the synthesis of arylamines include several steps. The production of aniline, for example, includes the following steps: the production of nitro-benzene by the nitration of benzene, and the reduction of the resulting nitro-benzene by catalytic hydrogenation or other reduction ways[1-6]; or the substitution of phenol or chlorbenzene by amino groups, etc.[7-10]. There are several disadvantages for these methods: low atom utilization, strict operation condition, large amount of by-products and serious environmental pollution, which could not afford for the needs of a sustainable civilization. So there has been growing interest in the direct amination to produce arylamines recently. With the direct methods, the multi- step reaction may change into one step, the atom utilization can be evidently improved, and the by-products H2 or/and H2O are harmless to the environment.

  7. Graphite Oxide and Aromatic Amines : Size Matters

    NARCIS (Netherlands)

    Spyrou, Konstantinos; Calvaresi, Matteo; Diamanti, Evmorfi A. K.; Tsoufis, Theodoros; Gournis, Dimitrios; Rudolf, Petra; Zerbetto, Francesco

    2015-01-01

    Experimental and theoretical studies are performed in order to illuminate, for first time, the intercalation mechanism of polycyclic aromatic molecules into graphite oxide. Two representative molecules of this family, aniline and naphthalene amine are investigated. After intercalation, aniline molec

  8. Amines as occupational hazards for visual disturbance

    Science.gov (United States)

    JANG, Jae-Kil

    2015-01-01

    Various amines, such as triethylamine and N,N-dimethylethylamine, have been reported to cause glaucopsia in workers employed in epoxy, foundry, and polyurethane foam industries. This symptom has been related to corneal edema and vesicular collection of fluid within the corneal subepithelial cells. Exposure to amine vapors for 30 min to several hours leads to blurring of vision, a blue-grey appearance of objects, and halos around lights, that are probably reversible. Concentration-effect relationships have been established. The visual disturbance is considered a nuisance, as it could cause onsite accidents, impair work efficiency, and create difficulties in driving back home. Occupational exposure limits have been established for some amines, but there is shortage of criteria. Volatility factors, such as vapor pressure, should be considered in industrial settings to prevent human ocular risks, while trying to reduce levels of hazardous amines in the atmosphere. PMID:26538000

  9. Multiple amine oxidases in cucumber seedlings.

    Science.gov (United States)

    Percival, F W; Purves, W K

    1974-10-01

    Cell-free extracts of cucumber (Cucumis sativus L. cv. National Pickling) seedlings were found to have amine oxidase activity when assayed with tryptamine as a substrate. Studies of the effect of lowered pH on the extract indicated that this activity was heterogeneous, and three amine oxidases could be separated by ion exchange chromatography. The partially purified enzymes were tested for their activities with several substrates and for their sensitivities to various amine oxidase inhibitors. One of the enzymes may be a monoamine oxidase, although it is inhibited by some diamine oxidase inhibitors. The other two enzymes have properties more characteristic of the diamine oxidases. The possible relationship of the amine oxidases to indoleacetic acid biosynthesis in cucumber seedlings is discussed.

  10. Aromatic amines sources, environmental impact and remediation

    OpenAIRE

    Pereira, Luciana; Mondal, P. K.; Alves, M. M.

    2015-01-01

    Aromatic amines are widely used industrial chemicals as their major sources in the environment include several chemical industry sectors such as oil refining, synthetic polymers, dyes, adhesives, rubbers, perfume, pharmaceuticals, pesticides and explosives. They result also from diesel exhaust, combustion of wood chips and rubber and tobacco smoke. Some types of aromatic amines are generated during cooking, special grilled meat and fish, as well. The intensive use and production of these comp...

  11. Enhancing amine terminals in an amine-deprived collagen matrix.

    LENUS (Irish Health Repository)

    Tiong, William H C

    2008-10-21

    Collagen, though widely used as a core biomaterial in many clinical applications, is often limited by its rapid degradability which prevents full exploitation of its potential in vivo. Polyamidoamine (PAMAM) dendrimer, a highly branched macromolecule, possesses versatile multiterminal amine surface groups that enable them to be tethered to collagen molecules and enhance their potential. In this study, we hypothesized that incorporation of PAMAM dendrimer in a collagen matrix through cross-linking will result in a durable, cross-linked collagen biomaterial with free -NH 2 groups available for further multi-biomolecular tethering. The aim of this study was to assess the physicochemical properties of a G1 PAMAM cross-linked collagen matrix and its cellular sustainability in vitro. Different amounts of G1 PAMAM dendrimer (5 or 10 mg) were integrated into bovine-derived collagen matrices through a cross-linking process, mediated by 5 or 25 mM 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) in 5 mM N-hydroxysuccinimide (NHS) and 50 mM 2-morpholinoethane sulfonic acid buffer at pH 5.5. The physicochemical properties of resultant matrices were investigated with scanning electron microscopy (SEM), collagenase degradation assay, differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectra, and ninhydrin assay. Cellular sustainability of the matrices was assessed with Alamar Blue assay and SEM. There was no significant difference in cellular behavior between the treated and nontreated groups. However, the benefit of incorporating PAMAM in the cross-linking reaction was limited when higher concentrations of either agent were used. These results confirm the hypothesis that PAMAM dendrimer can be incorporated in the collagen cross-linking process in order to modulate the properties of the resulting cross-linked collagen biomaterial with free -NH 2 groups available for multi-biomolecular tethering.

  12. Multilayered Thin Films from Poly(amido amine)s and DNA

    NARCIS (Netherlands)

    Hujaya, S.D.; Engbersen, J.F.J.; Paulusse, J.M.J.

    2015-01-01

    Dip-coated multilayered thin films of poly(amido amine)s (PAAs) and DNA have been developed to provide surfaces with cell-transfecting capabilities. Three types of PAAs, differing in side chain functional groups, were synthesized and characterized for their properties in forming multilayered structu

  13. Accurate determination of aldehydes in amine catalysts or amines by 2,4-dinitrophenylhydrazine derivatization.

    Science.gov (United States)

    Barman, Bhajendra N

    2014-01-31

    Carbonyl compounds, specifically aldehydes, present in amine catalysts or amines are determined by reversed-phase liquid chromatography using ultraviolet detection of their corresponding 2,4-dinitrophenylhydrazones. The primary focus has been to establish optimum conditions for determining aldehydes accurately because these add exposure concerns when the amine catalysts are used to manufacture polyurethane products. Concentrations of aldehydes determined by this method are found to vary with the pH of the aqueous amine solution and the derivatization time, the latter being problematic when the derivatization reaction proceeds slowly and not to completion in neutral and basic media. Accurate determination of aldehydes in amines through derivatization can be carried out at an effective solution pH of about 2 and with derivatization time of 20min. Hydrochloric acid has been used for neutralization of an amine. For complete derivatization, it is essential to protonate all nitrogen atoms in the amine. An approach for the determination of an adequate amount of acid needed for complete derivatization has been described. Several 0.2M buffer solutions varying in pH from 4 to 8 have also been used to make amine solutions for carrying out derivatization of aldehydes. These solutions have effective pHs of 10 or higher and provide much lower aldehyde concentrations compared to their true values. Mechanisms for the formation of 2,4-dinitrophenylhydrazones in both acidic and basic media are discussed.

  14. Reductive Amination of Aldehydes and Ketones with Primary Amines by Using Lithium Amidoborane as Reducing Reagent

    Institute of Scientific and Technical Information of China (English)

    徐维亮; 郑学丽; 吴国涛; 陈萍

    2012-01-01

    A variety of secondary amines were obtained in high isolated yields in the reductive amination of aldehydes and ketones by using lithium amidoborane as reducing agent. Compared to ammonia borane, lithium amidoborane has higher reducibility, and thus, exhibits faster reaction rate.

  15. CCN activity of aliphatic amine secondary aerosol

    Directory of Open Access Journals (Sweden)

    X. Tang

    2014-01-01

    Full Text Available Aliphatic amines can form secondary aerosol via oxidation with atmospheric radicals (e.g. hydroxyl radical and nitrate radical. The particle composition can contain both secondary organic aerosol (SOA and inorganic salts. The fraction of organic to inorganic materials in the particulate phase influences aerosol hygroscopicity and cloud condensation nuclei (CCN activity. SOA formed from trimethylamine (TMA and butylamine (BA reactions with hydroxyl radical (OH is composed of organic material of low hygroscopicity (single hygroscopicity parameter, κ ≤ 0.25. Secondary aerosol formed from the tertiary aliphatic amine (TMA with N2O5 (source of nitrate radical, NO3, contains less volatile compounds than the primary aliphatic amine (BA aerosol. TMA + N2O5 form semi-volatile organics in low RH conditions that have κ ~ 0.20, indicative of slightly soluble organic material. As RH increases, several inorganic amine salts are formed as a result of acid-base reactions. The CCN activity of the humid TMA-N2O5 aerosol obeys Zdanovskii, Stokes, and Robinson (ZSR ideal mixing rules. Higher CCN activity (κ > 0.3 was also observed for humid BA+N2O5 aerosols compared with dry aerosol (κ ~ 0.2, as a result of the formation of inorganic salts such as NH4NO3 and butylamine nitrate (C4H11N · HNO3. Compared with TMA, BA+N2O5 reactions produce more volatile aerosols. The BA+N2O5 aerosol products under humid experiments were found to be very sensitive to the temperature within the stream-wise continuous flow thermal gradient CCN counter. The CCN counter, when set above a 21 °C temperature difference, evaporates BA+N2O5 aerosol formed at RH ≥ 30%; κ ranges from 0.4 to 0.7 and is dependent on the instrument supersaturation (ss settings. The aerosol behaves non-ideally, hence simple ZSR rules cannot be applied to the CCN results from the primary aliphatic amine system. Overall, aliphatic amine aerosol systems κ ranges from 0.2 < κ < 0.7. This work indicates that

  16. BIOGENIC AMINES CONTENT IN DIFFERENT WINE SAMPLES

    Directory of Open Access Journals (Sweden)

    Attila Kántor

    2015-02-01

    Full Text Available Twenty-five samples of different Slovak wines before and after filtration were analysed in order to determine the content of eight biogenic amines (tryptamine, phenylalanine, putrescine, cadaverine, histamine, tyramine, spermidine and spermine. The method involves extraction of biogenic amines from wine samples with used dansyl chloride. Ultra-high performance liquid chromatography (UHPLC was used for determination of biogenic amines equipped with a Rapid Resolution High Definition (RRHD, DAD detectors and Extend-C18 LC column (50 mm x 3.0 mm ID, 1.8 μm particle size. In this study the highest level of biogenic amine in all wine samples represent tryptamine (TRM with the highest content 170.9±5.3 mg/L in Pinot Blanc wine. Phenylalanine (PHE cadaverine (CAD, histamine (HIS and spermidine (SPD were not detected in all wines; mainly SPD was not detected in 16 wines, HIS not detected in 14 wines, PHE and CAD not detected in 2 wines. Tyramine (TYR, spermine (SPN and putrescine (PUT were detected in all wines, but PUT and SPN in very low concentration. The worst wine samples with high biogenic amine content were Saint Laurent (BF, Pinot Blanc (S and Pinot Noir (AF.

  17. Biogenic amines in raw and processed seafood

    Directory of Open Access Journals (Sweden)

    Pierina eVisciano

    2012-06-01

    Full Text Available The presence of biogenic amines in raw and processed seafood, associated with either time/temperature conditions or food technologies is discussed in the present paper from a safety and prevention point of view. In particular, storage temperature, handling practices, presence of microbial populations with decarboxylase activity and availability of free amino acids are considered the most important factors affecting the production of biogenic amines in raw seafood. On the other hand, some food technological treatments such as salting, ripening, fermentation or marination can increase the levels of biogenic amines in processed seafood. The consumption of high amount of biogenic amines, above all histamine, can result in food borne poisoning which is a worldwide problem. The European Regulation established as maximum limits for histamine, in fishery products from fish species associated with high histidine amounts, values ranging from 100 to 200 mg/kg, while for products which have undergone enzyme maturation treatment in brine, the aforementioned limits rise to 200 and 400 mg/kg. Preventive measures and emerging methods aiming at controlling the production of biogenic amines are also reported for potential application in seafood industries.

  18. Amine permeation sources characterized with acid neutralization and sensitivities of an amine mass spectrometer

    Science.gov (United States)

    Freshour, N. A.; Carlson, K. K.; Melka, Y. A.; Hinz, S.; Panta, B.; Hanson, D. R.

    2014-10-01

    An acid titration method for quantifying amine permeation rates was used to calibrate an Ambient pressure Proton transfer Mass Spectrometer (AmPMS) that monitors ambient amine compounds. The method involves capturing amines entrained in a N2 flow by bubbling it through an acidified solution (~10-5 M HCl), and the amines are quantified via changes in solution pH with time. Home-made permeation tubes had permeation rates (typically tens of pmol s-1) that depended on the type of amine and tubing and on temperature. Calibrations of AmPMS yielded sensitivities for ammonia, methylamine, dimethylamine, and trimethylamine that are close to the sensitivity assuming a gas-kinetic, ion-molecule rate coefficient. The permeation tubes were also designed to deliver a reproducible amount of amine to a flow reactor where nucleation with sulfuric acid was studied. The high proton affinity compound dimethyl sulfoxide (DMSO), linked to oceanic environments, was also studied and AmPMS is highly sensitive to it. AmPMS was deployed recently in two field campaigns and, using these sensitivities, mixing ratios for ammonia and the alkyl amines are derived from the signals. Correlations between these species and with particle formation events are discussed.

  19. Interaction between hypocrellin and aliphatic amines

    Institute of Scientific and Technical Information of China (English)

    张曼华; 陈申; 夏万林; 蒋丽金; 陈德文

    1996-01-01

    The interaction of hypocrellin, including hypocrellin A (HA) and hypocrellin B (HB), with aliphatic amines in deaerated solutions has been studied by ESR and nanosecond transient absorption spectra. In polar solvents, the acid-base interaction between hypocrellin and amines was observed without irradiation. The signals of semiquinone radical anions of hypocrellm and the spin-trapping adduct of α-phenyl-N-tertbutyl-ratrone (PNB) with the aminoalkyl radicals have been detected in photoinduced ESR studies. The transient absorption of excited triplet state of HA and semiquinone radical anion of HA have been observed in laser flash photolysis studies.

  20. Enantioselective catalytic syntheses of alpha-branched chiral amines

    DEFF Research Database (Denmark)

    Brase, S.; Baumann, T.; Dahmen, S.

    2007-01-01

    Chiral amines play a pivotal role in fine chemical and natural product syntheses and the design of novel materials.......Chiral amines play a pivotal role in fine chemical and natural product syntheses and the design of novel materials....

  1. Tertiary amines nucleophilicity in quaternization reaction with benzyl chloride

    Directory of Open Access Journals (Sweden)

    Ksenia S. Yutilova

    2016-03-01

    Full Text Available Quaternization reaction of tertiary amines with benzyl chloride was investigated. Reaction orders with respect to the reactants were determined. Kinetic scheme of quaternization reaction was found to be corresponding to reversible process. An influence of amines basicity and steric factor of alkyl substituent bound to the nitrogen atom on tertiary amines reactivity as nucleophiles was studied. It was shown that the rate constants of direct reaction step may serve as a measure of nucleophilicity of amines.

  2. Catalytic Amination of Alcohols, Aldehydes, and Ketones

    Science.gov (United States)

    Klyuev, M. V.; Khidekel', M. L.

    1980-01-01

    Data on the catalytic amination of alcohols and carbonyl compounds are examined, the catalysts for these processes are described, and the problems of their effectiveness, selectivity, and stability are discussed. The possible mechanisms of the reactions indicated are presented. The bibliography includes 266 references.

  3. Fate and biodegradability of sulfonated aromatic amines

    NARCIS (Netherlands)

    Tan, N.C.G.; Leeuwen, van A.; Voorthuizen, van E.M.; Slenders, P.; Prenafeta, F.X.; Temmink, H.; Lettinga, G.; Field, J.A.

    2005-01-01

    Ten sulfonated aromatic amines were tested for their aerobic and anaerobic biodegradability and toxicity potential in a variety of environmental inocula. Of all the compounds tested, only two aminobenzenesulfonic acid (ABS) isomers, 2- and 4-ABS, were degraded. The observed degradation occurred only

  4. CCN activity of aliphatic amine secondary aerosol

    Science.gov (United States)

    Tang, X.; Price, D.; Praske, E.; Vu, D.; Purvis-Roberts, K.; Silva, P. J.; Cocker, D. R., III; Asa-Awuku, A.

    2014-01-01

    Aliphatic amines can form secondary aerosol via oxidation with atmospheric radicals (e.g. hydroxyl radical and nitrate radical). The particle composition can contain both secondary organic aerosol (SOA) and inorganic salts. The fraction of organic to inorganic materials in the particulate phase influences aerosol hygroscopicity and cloud condensation nuclei (CCN) activity. SOA formed from trimethylamine (TMA) and butylamine (BA) reactions with hydroxyl radical (OH) is composed of organic material of low hygroscopicity (single hygroscopicity parameter, κ ≤ 0.25). Secondary aerosol formed from the tertiary aliphatic amine (TMA) with N2O5 (source of nitrate radical, NO3), contains less volatile compounds than the primary aliphatic amine (BA) aerosol. TMA + N2O5 form semi-volatile organics in low RH conditions that have κ ~ 0.20, indicative of slightly soluble organic material. As RH increases, several inorganic amine salts are formed as a result of acid-base reactions. The CCN activity of the humid TMA-N2O5 aerosol obeys Zdanovskii, Stokes, and Robinson (ZSR) ideal mixing rules. Higher CCN activity (κ > 0.3) was also observed for humid BA+N2O5 aerosols compared with dry aerosol (κ ~ 0.2), as a result of the formation of inorganic salts such as NH4NO3 and butylamine nitrate (C4H11N · HNO3). Compared with TMA, BA+N2O5 reactions produce more volatile aerosols. The BA+N2O5 aerosol products under humid experiments were found to be very sensitive to the temperature within the stream-wise continuous flow thermal gradient CCN counter. The CCN counter, when set above a 21 °C temperature difference, evaporates BA+N2O5 aerosol formed at RH ≥ 30%; κ ranges from 0.4 to 0.7 and is dependent on the instrument supersaturation (ss) settings. The aerosol behaves non-ideally, hence simple ZSR rules cannot be applied to the CCN results from the primary aliphatic amine system. Overall, aliphatic amine aerosol systems κ ranges from 0.2 systems.

  5. Development of a general non-noble metal catalyst for the benign amination of alcohols with amines and ammonia.

    Science.gov (United States)

    Cui, Xinjiang; Dai, Xingchao; Deng, Youquan; Shi, Feng

    2013-03-11

    The N-alkylation of amines or ammonia with alcohols is a valuable route for the synthesis of N-alkyl amines. However, as a potentially clean and economic choice for N-alkyl amine synthesis, non-noble metal catalysts with high activity and good selectivity are rarely reported. Normally, they are severely limited due to low activity and poor generality. Herein, a simple NiCuFeOx catalyst was designed and prepared for the N-alkylation of ammonia or amines with alcohol or primary amines. N-alkyl amines with various structures were successfully synthesized in moderate to excellent yields in the absence of organic ligands and bases. Typically, primary amines could be efficiently transformed into secondary amines and N-heterocyclic compounds, and secondary amines could be N-alkylated to synthesize tertiary amines. Note that primary and secondary amines could be produced through a one-pot reaction of ammonia and alcohols. In addition to excellent catalytic performance, the catalyst itself possesses outstanding superiority, that is, it is air and moisture stable. Moreover, the magnetic property of this catalyst makes it easily separable from the reaction mixture and it could be recovered and reused for several runs without obvious deactivation.

  6. Catalytic dehydrogenation of amine borane complexes

    Science.gov (United States)

    Mohajeri, Nahid (Inventor); Tabatabaie-Raissi, Ali (Inventor); Bokerman, Gary (Inventor)

    2009-01-01

    A method of generating hydrogen includes the steps of providing an amine borane (AB) complex, at least one hydrogen generation catalyst, and a solvent, and mixing these components Hydrogen is generated. The hydrogen produced is high purity hydrogen suitable for PEM fuel cells. A hydrolytic in-situ hydrogen generator includes a first compartment that contains an amine borane (AB) complex, a second container including at least one hydrogen generation catalyst, wherein the first or second compartment includes water or other hydroxyl group containing solvent. A connecting network permits mixing contents in the first compartment with contents in the second compartment, wherein high purity hydrogen is generated upon mixing. At least one flow controller is provided for controlling a flow rate of the catalyst or AB complex.

  7. Organic chemistry. Strain-release amination.

    Science.gov (United States)

    Gianatassio, Ryan; Lopchuk, Justin M; Wang, Jie; Pan, Chung-Mao; Malins, Lara R; Prieto, Liher; Brandt, Thomas A; Collins, Michael R; Gallego, Gary M; Sach, Neal W; Spangler, Jillian E; Zhu, Huichin; Zhu, Jinjiang; Baran, Phil S

    2016-01-15

    To optimize drug candidates, modern medicinal chemists are increasingly turning to an unconventional structural motif: small, strained ring systems. However, the difficulty of introducing substituents such as bicyclo[1.1.1]pentanes, azetidines, or cyclobutanes often outweighs the challenge of synthesizing the parent scaffold itself. Thus, there is an urgent need for general methods to rapidly and directly append such groups onto core scaffolds. Here we report a general strategy to harness the embedded potential energy of effectively spring-loaded C-C and C-N bonds with the most oft-encountered nucleophiles in pharmaceutical chemistry, amines. Strain-release amination can diversify a range of substrates with a multitude of desirable bioisosteres at both the early and late stages of a synthesis. The technique has also been applied to peptide labeling and bioconjugation.

  8. Sonophotocatalytic Degradation of Amines in Water

    Science.gov (United States)

    Verman, Mayank; Pankaj

    Hazardous effects of various amines, produced in the environment from the partial degradation of azo dyes and amino acids, adversely affect the quality of human life through water, soil and air pollution and therefore needed to be degraded. A number of such studies are already available in the literature, with or without the use of ultrasound, which have been summarized briefly. The sonochemical degradation of amines and in the combination with a photocatalyst, TiO2 has also been discussed. Similar such degradation studies for ethylamine (EA), aniline (A), diphenylamine (DPA) and naphthylamine (NA) in the presence of ultrasound, TiO2 and rare earths (REs); La, Pr, Nd, Sm and Gd, in aqueous solutions at 20 kHz and 250 W power have been carried out and reported, to examine the combinatorial efficacy of ultrasound in the presence of a photocatalyst and rare earth ions with reactive f-electrons.

  9. Amine chemistry. Update on impact on resin

    Energy Technology Data Exchange (ETDEWEB)

    Bachman, Gregory; Kellogg, Douglas [Siemens Industry, Inc., Rockford, IL (United States). Technology and Lab Services; Wilkes, Marty [Siemens Industry, Inc., Rockford, IL (United States). Water Technologies Div.

    2012-03-15

    Impurity removal in the steam cycle and the associated prevention of corrosion and/or fouling of system components are the goals of ion exchange resins. However, in many instances (such as a switch to amine chemistry or a change in product specifications), resins do not remove, and, in fact, contribute impurities to the steam cycle. This paper reviews recent data compiled to determine the direct and indirect effects of amines on ion exchange resins used in the power industry. Water chemistries have improved in recent years, in large part due to changes in chemistry and resins, but it is necessary to continue to develop products, processes and techniques to reduce impurities and improve overall water chemistry in power plant systems. (orig.)

  10. O—Maltosylation of Heterocyclic Ketene Aminals

    Institute of Scientific and Technical Information of China (English)

    徐占辉; 黄志镗

    2002-01-01

    The stereoselective synthesis of O-maltosides by reacting benzoyl-substituted heterocyclic ketene aminals 1 or 2 with acetylated maltosyl bromide 3 was investigated.Compounds 1 or 2 reacted with 3 in the presence of mercuric cyanide to give O-maltosides 4 or 5 with E-configuration.While 1 reacted with 3 in the presence of calcium hydride to give O-maltosides 6 with Zconfiguration.

  11. O-Maltosylation of Heterocyclic Ketene Aminals

    Institute of Scientific and Technical Information of China (English)

    XU,Zhan-Hui(徐占辉); HUANG,Zhi-Tang(黄志镗)

    2002-01-01

    The stereoselective synthesis of O-maltosides by reacting benzoyl-substituted heterocyclic ketene aminals 1 or 2 with acetylated maltosyl bromide 3 was investigated. Compounds 1 or 2 reacted with 3 in the presence of mercuric cyanide to give O-maltosides 4 or 5 with E-configuration. While 1 reacted with 3 in the presence of calcium hydride to give O-maltosides 6 with Zconfiguration.

  12. Amine reactivity with charged sulfuric acid clusters

    Science.gov (United States)

    Bzdek, B. R.; Ridge, D. P.; Johnston, M. V.

    2011-08-01

    The distribution of charged species produced by electrospray of an ammonium sulfate solution in both positive and negative polarities is examined using Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS). Positively-charged ammonium bisulfate cluster composition differs significantly from negatively-charged cluster composition. For positively-charged clusters all sulfuric acid is neutralized to bisulfate, whereas for negatively-charged clusters the degree of sulfuric acid neutralization is cluster size-dependent. With increasing cluster size (and, therefore, a decreasing role of charge), both positively- and negatively-charged cluster compositions converge toward ammonium bisulfate. The reactivity of negatively-charged sulfuric acid-ammonia clusters with dimethylamine and ammonia is also investigated by FTICR-MS. Two series of negatively-charged clusters are investigated: [(HSO4)(H2SO4)x]- and [(NH4)x(HSO4)x+1(H2SO4)3]-. Dimethylamine substitution for ammonia in [(NH4) x(HSO4) x+1(H2SO4)3]- clusters is nearly collision-limited, and subsequent addition of dimethylamine to neutralize H2SO4 to bisulfate is within one order of magnitude of the substitution rate. Dimethylamine addition to [(HSO4) (H2SO4) x]- clusters is either not observed or very slow. The results of this study indicate that amine chemistry will be evident and important only in large ambient negative ions (>m/z 400), whereas amine chemistry may be evident in small ambient positive ions. Addition of ammonia to unneutralized clusters occurs at a rate that is ~2-3 orders of magnitude slower than incorporation of dimethylamine either by substitution or addition. Therefore, in locations where amine levels are within a few orders of magnitude of ammonia levels, amine chemistry may compete favorably with ammonia chemistry.

  13. Whole cell biotransformation for reductive amination reactions

    OpenAIRE

    Klatte, Stephanie; Lorenz, Elisabeth; Wendisch, Volker F.

    2013-01-01

    Whole cell biotransformation systems with enzyme cascading increasingly find application in biocatalysis to complement or replace established chemical synthetic routes for production of, e.g., fine chemicals. Recently, we established an Escherichia coli whole cell biotransformation system for reductive amination by coupling a transaminase and an amino acid dehydrogenase with glucose catabolism for cofactor recycling. Transformation of 2-keto-3-methylvalerate to l-isoleucine by E. coli cells w...

  14. Iridium- and Ruthenium-Catalyzed N-alkylation of Amines with Alcohols and Amines

    DEFF Research Database (Denmark)

    Lorentz-Petersen, Linda Luise Reeh

    via folding assisted ligation. One segment was synthesised as the C-terminal thioester by Boc-SPPS and the other segment as a C-terminal acid by Fmoc-SPPS. The sites of mutation were all in the α-helical region of the protein and the mutation choices were alanine and Aib, which both posses a high α...... is environmentally benign as it is performed in the absence of both solvent and additives and the only by-product is ammonia. Additionally, the work-up procedure is a simple distillation of the product directly from the reaction mixture. Synthesis of piperazines In the Madsen group it has previously been...... catalysts have been employed for the N-alkylation of amines with either alcohols or amines. Synthesis of secondary amines Self-condensation of primary amines afforded secondary amines in good to high yields. The reaction is catalyzed by the commercially available [Cp*IrCl2]2 complex. The procedure...

  15. Rett syndrome - Stimulation of endogenous biogenic amines

    Science.gov (United States)

    Pelligra, R.; Norton, R. D.; Wilkinson, R.; Leon, H. A.; Matson, W. R.

    1992-01-01

    Transient hypercapnic hyperoxemia was induced in two Rett syndrome children by the administration of a gaseous mixture of 80 percent O2 and 20 percent CO2. Time course studies of neurotransmitters and their metabolites showed an immediate and marked increase in central biogenic amine turnover following inhalation of the gas mixture. The increased turnover of biogenic amines was associated with improved clinical changes. This suggests a coupled relationship and provides further support for an etiological role of neurotransmitter dysfunction in Rett syndrome. In a complementary study, elevation of pulmonary CO2 by application of a simple rebreathing device resulted in improvement of abnormal blood gases and elimination of the Cheyne-Stokes-like respiratory pattern of the Rett syndrome. Near normalization of the EEG occurred when a normal respiratory pattern was imposed by means of a respirator. Taken together, these results lead to the preliminary conclusion that cerebral hypoxemia secondary to abnormal respiratory function may contribute to diminished production of biogenic amines in Rett syndrome.

  16. Amine Swingbed Payload Testing on ISS

    Science.gov (United States)

    Button, Amy B.; Sweterlitsch, Jeffrey J.

    2014-01-01

    One of NASA Johnson Space Center's test articles of the amine-based carbon dioxide (CO2) and water vapor sorbent system known as the CO2 And Moisture Removal Amine Swing-bed, or CAMRAS, was incorporated into a payload on the International Space Station (ISS). The intent of the payload is to demonstrate the spacecraft-environment viability of the core atmosphere revitalization technology baselined for the new Orion vehicle. In addition to the air blower, vacuum connection, and controls needed to run the CAMRAS, the payload incorporates a suite of sensors for scientific data gathering, a water save function, and an air save function. The water save function minimizes the atmospheric water vapor reaching the CAMRAS unit, thereby reducing ISS water losses that are otherwise acceptable, and even desirable, in the Orion environment. The air save function captures about half of the ullage air that would normally be vented overboard every time the cabin air-adsorbing and space vacuum-desorbing CAMRAS beds swap functions. The JSC team conducted 1000 hours of on-orbit Amine Swingbed Payload testing in 2013 and early 2014. This paper presents the basics of the payload's design and history, as well as a summary of the test results, including comparisons with prelaunch testing.

  17. New potential of the reductive alkylation of amines

    Science.gov (United States)

    Gusak, K. N.; Ignatovich, Zh V.; Koroleva, E. V.

    2015-03-01

    Available data on the reductive alkylation of amines with carbonyl compounds — a key method for the preparation of secondary and tertiary amines — are described systematically. The review provides information on the relevant reducing agents and catalysts and on the use of chiral catalysts in stereo- and enantiocontrolled reactions of amine synthesis. The effect of the reactant and catalyst structures on the reaction rates and chemo- and stereo(enantio)selectivity is considered. The bibliography includes 156 references.

  18. Amines and amine-related compounds in surface waters: a review of sources, concentrations and aquatic toxicity.

    Science.gov (United States)

    Poste, Amanda E; Grung, Merete; Wright, Richard F

    2014-05-15

    This review compiles available information on the concentrations, sources, fate and toxicity of amines and amine-related compounds in surface waters, including rivers, lakes, reservoirs, wetlands and seawater. There is a strong need for this information, especially given the emergence of amine-based post-combustion CO2 capture technologies, which may represent a new and significant source of amines to the environment. We identify a broad range of anthropogenic and natural sources of amines, nitrosamines and nitramines to the aquatic environment, and identify some key fate and degradation pathways of these compounds. There were very few data available on amines in surface waters, with reported concentrations often below detection and only rarely exceeding 10 μg/L. Reported concentrations for seawater and reservoirs were below detection or very low, while for lakes and rivers, concentrations spanned several orders of magnitude. The most prevalent and commonly detected amines were methylamine (MA), dimethylamine (DMA), ethylamine (EA), diethylamine (DEA) and monoethanolamine (MEAT). The paucity of data may reflect the analytical challenges posed by determination of amines in complex environmental matrices at ambient levels. We provide an overview of available aquatic toxicological data for amines and conclude that at current environmental concentrations, amines are not likely to be of toxicological concern to the aquatic environment, however, the potential for amines to act as precursors in the formation of nitrosamines and nitramines may represent a risk of contamination of drinking water supplies by these often carcinogenic compounds. More research on the prevalence and toxicity of amines, nitrosamines and nitramines in natural waters is necessary before the environmental impact of new point sources from carbon capture facilities can be adequately quantified.

  19. Amine reactivity with charged sulfuric acid clusters

    Directory of Open Access Journals (Sweden)

    B. R. Bzdek

    2011-08-01

    Full Text Available The distribution of charged species produced by electrospray of an ammonium sulfate solution in both positive and negative polarities is examined using Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS. Positively-charged ammonium bisulfate cluster composition differs significantly from negatively-charged cluster composition. For positively-charged clusters all sulfuric acid is neutralized to bisulfate, whereas for negatively-charged clusters the degree of sulfuric acid neutralization is cluster size-dependent. With increasing cluster size (and, therefore, a decreasing role of charge, both positively- and negatively-charged cluster compositions converge toward ammonium bisulfate. The reactivity of negatively-charged sulfuric acid-ammonia clusters with dimethylamine and ammonia is also investigated by FTICR-MS. Two series of negatively-charged clusters are investigated: [(HSO4(H2SO4x] and [(NH4x(HSO4x+1(H2SO43]. Dimethylamine substitution for ammonia in [(NH4 x(HSO4 x+1(H2SO43] clusters is nearly collision-limited, and subsequent addition of dimethylamine to neutralize H2SO4 to bisulfate is within one order of magnitude of the substitution rate. Dimethylamine addition to [(HSO4 (H2SO4 x] clusters is either not observed or very slow. The results of this study indicate that amine chemistry will be evident and important only in large ambient negative ions (>m/z 400, whereas amine chemistry may be evident in small ambient positive ions. Addition of ammonia to unneutralized clusters occurs at a rate that is ~2–3 orders of magnitude slower than incorporation of dimethylamine either by substitution or addition

  20. Amine reactivity with charged sulfuric acid clusters

    Directory of Open Access Journals (Sweden)

    B. R. Bzdek

    2011-05-01

    Full Text Available The distribution of ionic species produced by electrospray of an ammonium sulfate solution in both positive and negative polarities is examined using Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS. Positively-charged ammonium bisulfate cluster composition differs significantly from negatively-charged cluster composition. For positively-charged clusters all sulfuric acid is neutralized to bisulfate, whereas for negatively-charged clusters the degree of sulfuric acid neutralization is cluster size-dependent. With increasing cluster size (and, therefore, a decreasing role of charge, both positively- and negatively-charged cluster compositions converge toward ammonium bisulfate. The reactivity of negatively-charged sulfuric acid-ammonia clusters with dimethylamine and ammonia are also investigated by FTICR-MS. Two series of negatively-charged clusters are investigated: [(HSO4(H2SO4x] and [(NH4x(HSO4x+1(H2SO43]. Dimethylamine substitution for ammonia in [(NH4x(HSO4x+1(H2SO43] clusters is nearly collision-limited, and subsequent addition of dimethylamine to neutralize H2SO4 is within one order of magnitude of the substitution rate. Dimethylamine addition to [(HSO4(H2SO4x]clusters is either not observed or very slow. The results of this study indicate that amine chemistry will be evident and important only in large ambient negative ions (> m/z 400, whereas amine chemistry may be evident in small ambient positive ions. Addition of ammonia to unneutralized clusters occurs at a rate that is ~2–3 orders of magnitude slower than incorporation of dimethylamine either by

  1. Controlling Nitrosamines, Nitramines, and Amines in Amine-Based CO₂ Capture Systems with Continuous Ultraviolet and Ozone Treatment of Washwater.

    Science.gov (United States)

    Dai, Ning; Mitch, William A

    2015-07-21

    Formation of nitrosamines and nitramines from reactions between flue gas NOx and the amines used in CO2 capture units has arisen as a significant concern. Washwater scrubbers can capture nitrosamines and nitramines. They can also capture amines, preventing formation of nitrosamines and nitramines downwind by amine reactions with ambient NOx. The continuous application of UV alone, or a combination of UV and ozone to the return line of a washwater treatment unit was evaluated to control the accumulation of nitrosamines, nitramines and amines in a laboratory-scale washwater unit. With model secondary amine solvents ranging from nonvolatile diethanolamine to volatile morpholine, application of 272-537 mJ/cm(2) UV incident fluence alone reduced the accumulation of nitrosamines and nitramines by approximately an order of magnitude. Modeling indicated that the gains achieved by UV treatment should increase over time, because UV treatment converts the time dependence of nitrosamine accumulation from a quadratic to a linear function. Ozone (21 mg/L) maintained low steady-state concentrations of amines in the washwater. While modeling indicated that more than 80% of nitrosamine accumulation in the washwater was associated with reaction of washwater amines with residual NOx, a reduction in nitrosamine accumulation rates due to ozone oxidation of amines was not fully realized because the ozonation products of amines reduced nitrosamine photolysis rates by competing for photons.

  2. Trace Amines and the Trace Amine-Associated Receptor 1: Pharmacology, Neurochemistry, and Clinical Implications.

    Science.gov (United States)

    Pei, Yue; Asif-Malik, Aman; Canales, Juan J

    2016-01-01

    Biogenic amines are a collection of endogenous molecules that play pivotal roles as neurotransmitters and hormones. In addition to the "classical" biogenic amines resulting from decarboxylation of aromatic acids, including dopamine (DA), norepinephrine, epinephrine, serotonin (5-HT), and histamine, other biogenic amines, present at much lower concentrations in the central nervous system (CNS), and hence referred to as "trace" amines (TAs), are now recognized to play significant neurophysiological and behavioral functions. At the turn of the century, the discovery of the trace amine-associated receptor 1 (TAAR1), a phylogenetically conserved G protein-coupled receptor that is responsive to both TAs, such as β-phenylethylamine, octopamine, and tyramine, and structurally-related amphetamines, unveiled mechanisms of action for TAs other than interference with aminergic pathways, laying the foundations for deciphering the functional significance of TAs and its mammalian CNS receptor, TAAR1. Although, its molecular interactions and downstream targets have not been fully elucidated, TAAR1 activation triggers accumulation of intracellular cAMP, modulates PKA and PKC signaling and interferes with the β-arrestin2-dependent pathway via G protein-independent mechanisms. TAAR1 is uniquely positioned to exert direct control over DA and 5-HT neuronal firing and release, which has profound implications for understanding the pathophysiology of, and therefore designing more efficacious therapeutic interventions for, a range of neuropsychiatric disorders that involve aminergic dysregulation, including Parkinson's disease, schizophrenia, mood disorders, and addiction. Indeed, the recent development of novel pharmacological tools targeting TAAR1 has uncovered the remarkable potential of TAAR1-based medications as new generation pharmacotherapies in neuropsychiatry. This review summarizes recent developments in the study of TAs and TAAR1, their intricate neurochemistry and

  3. Preparation and characterization of amine-functionalized sugarcane bagasse for CO2 capture.

    Science.gov (United States)

    Luo, Shihe; Chen, Siyu; Chen, Shuixia; Zhuang, Linzhou; Ma, Nianfang; Xu, Teng; Li, Qihan; Hou, Xunan

    2016-03-01

    A low-cost solid amine adsorbent for CO2 capture was prepared by using sugarcane bagasse (SB), a dominant agro-industrial residue in the sugar and alcohol industry as raw materials. In this preparation process, acrylamide was grafted on SB, and the grafted fiber was then aminated with different type of amine reagents to introduce primary and secondary amine groups onto the surface of SB fibers. The graft and amination conditions were optimized. The prepared solid amine adsorbent showed remarkable CO2 adsorption capacity and the adsorption capacity of the solid amine adsorbent could reach 5.01 mmol CO2/g at room temperature. The comparison of adsorption capacities of amine fibers aminated with various amination agents demonstrated that fibers aminated with triethylenetetramine would obtain higher adsorption capacities and higher amine efficiency. These adsorbents also showed good regeneration performance, the regenerated adsorbent could maintain almost the same adsorption capacity for CO2 after 10 recycles.

  4. Thermodynamics of organic mixtures containing amines

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, Juan Antonio [G.E.T.E.F. Dpto Termodinamica y Fisica Aplicada, Facultad de Ciencias, Universidad de Valladolid, Valladolid 47071 (Spain)]. E-mail: jagl@termo.uva.es; Mozo, Ismael [G.E.T.E.F. Dpto Termodinamica y Fisica Aplicada, Facultad de Ciencias, Universidad de Valladolid, Valladolid 47071 (Spain); Fuente, Isaias Garcia de la [G.E.T.E.F. Dpto Termodinamica y Fisica Aplicada, Facultad de Ciencias, Universidad de Valladolid, Valladolid 47071 (Spain); Cobos, Jose Carlos [G.E.T.E.F. Dpto Termodinamica y Fisica Aplicada, Facultad de Ciencias, Universidad de Valladolid, Valladolid 47071 (Spain)

    2006-02-01

    Binary mixtures containing pyridine (PY), or 2-methylpyridine (2MPY) or 3-methylpyridine (3MPY) or 4-methylpyridine (4MPY) and an organic solvent as benzene, toluene, alkane, or 1-alkanol are investigated in the framework of DISQUAC. The corresponding interaction parameters are reported. The model describes accurately a whole set of thermodynamic properties: vapor-liquid equilibria (VLE), liquid-liquid equilibria (LLE), solid-liquid equilibria (SLE), molar excess Gibbs energies (G{sup E}), molar excess enthalpies (H{sup E}), molar excess heat capacities at constant pressure (C{sub P}{sup E}) and the concentration-concentration structure factor (S{sub CC}(0)). It is remarkable that DISQUAC correctly predicts the W-shaped curve of the C{sub P}{sup E} of the pyridine + n-hexadecane system. The model can be applied successfully to mixtures with strong positive or negative deviations from the Raoult's law. DISQUAC improves the theoretical results from UNIFAC (Dortmund version). The replacement of pyridine by a methylpyridine leads to a weakening of the amine-amine interactions, ascribed to the steric effect caused by the methyl group attached to the aromatic ring. This explains that for a given solvent (alkane, 1-alkanol) H{sup E}(pyridine)>H{sup E}(methylpyridine)

  5. Conditions allowing the formation of biogenic amines in cheese.

    NARCIS (Netherlands)

    Joosten, H.M.L.J.

    1988-01-01

    A study was undertaken to reveal the conditions that allow the formation of biogenic amines in cheese.The starters most commonly used in the Dutch cheese industry do not have decarboxylative properties. Only if the milk or curd is contaminated with non-starter bacteria, amine formation may be observ

  6. Amination of allylic alcohols in water at room temperature.

    Science.gov (United States)

    Nishikata, Takashi; Lipshutz, Bruce H

    2009-06-04

    The "trick" to carrying out regiocontrolled aminations of allylic alcohols in water as the only medium is use of a nanomicelle's interior as the organic reaction solvent. When HCO(2)Me is present, along with the proper base and source of catalytic Pd, allylic amines are cleanly formed at room temperature.

  7. Effects of dietary amines on the gut and its vasculature.

    Science.gov (United States)

    Broadley, Kenneth J; Akhtar Anwar, M; Herbert, Amy A; Fehler, Martina; Jones, Elen M; Davies, Wyn E; Kidd, Emma J; Ford, William R

    2009-06-01

    Trace amines, including tyramine and beta-phenylethylamine (beta-PEA), are constituents of many foods including chocolate, cheeses and wines and are generated by so-called 'friendly' bacteria such as Lactobacillus, Lactococcus and Enterococcus species, which are found in probiotics. We therefore examined whether these dietary amines could exert pharmacological effects on the gut and its vasculature. In the present study we examined the effects of tyramine and beta-PEA on the contractile activity of guinea-pig and rat ileum and upon the isolated mesenteric vasculature and other blood vessels. Traditionally, these amines are regarded as sympathomimetic amines, exerting effects through the release of noradrenaline from sympathetic nerve endings, which should relax the gut. A secondary aim was therefore to confirm this mechanism of action. However, contractile effects were observed in the gut and these were independent of noradrenaline, acetylcholine, histamine and serotonin receptors. They were therefore probably due to the recently described trace amine-associated receptors. These amines relaxed the mesenteric vasculature. In contrast, the aorta and coronary arteries were constricted, a response that was also independent of a sympathomimetic action. From these results, we propose that after ingestion, trace amines could stimulate the gut and improve intestinal blood flow. Restriction of blood flow elsewhere diverts blood to the gut to aid digestion. Thus, trace amines in the diet may promote the digestive process through stimulation of the gut and improved gastrointestinal circulation.

  8. Nitrosamine formation in amine scrubbing at desorber temperatures.

    Science.gov (United States)

    Fine, Nathan A; Goldman, Mark J; Rochelle, Gary T

    2014-01-01

    Amine scrubbing is a thermodynamically efficient and industrially proven method for carbon capture, but amine solvents can nitrosate in the desorber, forming potentially carcinogenic nitrosamines. The kinetics of reactions involving nitrite and monoethanolamine (MEA), diethanolamine (DEA), methylethanolamine (MMEA), and methyldiethanolamine (MDEA) were determined under desorber conditions. The nitrosations of MEA, DEA, and MMEA are first order in nitrite, carbamate species, and hydronium ion. Nitrosation of MDEA, a tertiary amine, is not catalyzed by the addition of CO2 since it cannot form a stable carbamate. Concentrated and CO2 loaded MEA was blended with low concentrations of N-(2-hydroxyethyl) glycine (HeGly), hydroxyethyl-ethylenediamine (HEEDA), and DEA, secondary amines common in MEA degradation. Nitrosamine yield was proportional to the concentration of secondary amine and was a function of CO2 loading and temperature. Blends of tertiary amines with piperazine (PZ) showed n-nitrosopiperazine (MNPZ) yields close to unity, validating the slow nitrosation rates hypothesized for tertiary amines. These results provide a useful tool for estimating nitrosamine accumulation over a range of amine solvents.

  9. 40 CFR 721.6140 - Dialkyldithiophosphoric acid, aliphatic amine salt.

    Science.gov (United States)

    2010-07-01

    ... Specific Chemical Substances § 721.6140 Dialkyldithiophosphoric acid, aliphatic amine salt. (a) Chemical... as a dialkyldithiophosphoric acid, aliphatic amine salt (P-90-1839) is subject to reporting under... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Dialkyldithiophosphoric...

  10. ELPI+ measurements of aerosol growth in an amine absorption column

    NARCIS (Netherlands)

    Mertens, J.; Brachert, L.; Desagher, D.; Thielens, M.L.; Khakharia, P.M.; Goetheer, E.L.V.; Schaber, K.

    2014-01-01

    Recently, studies have appeared pointing out that aerosols can dominate the total amine emission from amine based PCCC pilot plant scale installations. For the design of countermeasure types (upstream or downstream of the PCCC installation), it is crucial to have an idea of the aerosol size distribu

  11. Factors influencing biogenic amines accumulation in dairy products

    Directory of Open Access Journals (Sweden)

    Daniel M. eLinares

    2012-05-01

    Full Text Available Fermented foods are within the food products more often complained of having caused biogenic amines poisoning. Concerning milk-based fermented foods, cheese is the main product likely to contain significant levels of biogenic amines, specially tyramine, histamine and putrescine. Prompted by the increasing awareness of the risks related to dietary uptake of high biogenic amine loads, in this review we report about cheese elaboration and processing technological aspects affecting biogenic amines levels. Synthesis of biogenic amines is possible only when three conditions converge: i availability of the substrate amino acids; ii presence of microorganisms with the appropriate catabolic pathway activated; and iii environmental conditions favorable to the decarboxilation activity. These conditions depend on several factors such as milk treatment (pasteurization, use of starter cultures, NaCl concentration, time and temperature of ripening and preservation, pH… which will be discussed in this chapter.

  12. Amine Reactivity with Nanoclusters of Sulfuric Acid and Ammonia

    Science.gov (United States)

    Johnston, M. V.; Bzdek, B. R.; DePalma, J.

    2011-12-01

    Alkyl amines have emerged as key species in new particle formation and growth. This interest is reinforced by ambient measurements of amines (e.g. Smith et al., 2010) and enhanced levels of nitrogen (e.g. Bzdek et al., 2011) during growth of newly formed particles. An important mechanism of amine uptake is aminium salt formation, either by substituting for ammonium ions that already exist in the particle or by opening new channels for salt formation that are not favorable with ammonia. This presentation will focus on recent experimental and computational work in our group to study amine uptake into charged nanoclusters of sulfuric acid and ammonia. In the experimental work, clusters are produced by electrospray of an ammonium sulfate solution and then drawn into a Fourier transform ion cyclotron resonance mass spectrometer where a specific cluster is isolated and exposed to amine vapor. We find that amine reactivity is dependent on the size, composition and charge of the isolated cluster. For small clusters of either polarity, all ammonium ions reside on the surface and amine substitution occurs with near unit reaction probability. As the cluster size increases, an ammonium ion can be encapsulated in the center of the cluster, which provides a steric hindrance to amine substitution. Negatively charged clusters are more likely to be acidic than positively charged clusters. For acidic clusters, incoming amine molecules first substitute for preexisting ammonium ions and then add to the cluster until a "neutralized" aminium bisulfate composition is reached. Computational studies of these clusters provide fundamental insight into the thermodynamics and kinetics of amine uptake.

  13. Synthesis and characterization of bisimide amines and bisimide amine-cured epoxy resins

    Science.gov (United States)

    Scola, D. A.

    1983-01-01

    An attempt is made to develop tough, moisture resistant, high char yield epoxy resins by means of novel bisimide amine (BIA) hardener curing agents and a state-of-the-art epoxy resin system. The BIAs are isolated as mixtures containing monomer, oligomer, and polymeric species, and then characterized by elemental analysis and high pressure liquid chromatography. The bisimide amine-cured epoxies (IMEs) were characterized with respect to moisture absorption, thermal properties, and physical and mechanical properties, as well as in the role of matrices in Celion 6000/IME composites. The relative toughness characteristics of each IME formulation was measured by the 10 deg off-axis tensile test, measuring the uniaxial tensile strength, shear strength, and shear-strain-to-failure of the composite systems.

  14. Electrochemical characterization of aminated acrylic conducting polymer

    Energy Technology Data Exchange (ETDEWEB)

    Rashid, Norma Mohammad [School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Lestari Universiti Kebangsaan Malaysia (UKM), 43600 Bangi, Selangor Darul Ehsan (Malaysia); Heng, Lee Yook [School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Lestari Universiti Kebangsaan Malaysia (UKM), 43600 Bangi, Selangor Darul Ehsan (Malaysia); Southeast Asia Disaster Prevention Research Initiative, Lestari Universiti Kebangsaan Malaysia (UKM), 43600 Bangi, Selangor Darul Ehsan (Malaysia); Ling, Tan Ling [Southeast Asia Disaster Prevention Research Initiative, Lestari Universiti Kebangsaan Malaysia (UKM), 43600 Bangi, Selangor Darul Ehsan (Malaysia)

    2015-09-25

    New attempt has been made to synthesize aminated acrylic conducting polymer (AACP) using precursor of phenylvinylsulfoxide (PVS). The process was conducted via the integration of microemulsion and photopolymerization techniques. It has been utilized for covalent immobilization of amino groups by the adding of N-achryiloxisuccinimide (NAS). Thermal eliminating of benzene sulfenic acids from PVS has been done at 250 °C to form electroactive polyacetylene (PA) segment. Characterization of AACP has been conducted using fourier transform infrared (FTIR), scanning electron microscopy (SEM) and linear sweep cyclic voltammetry (CV). A range of 0.3-1.25μm particle size obtained from SEM characterization. A quasi-reversible system performed as shown in electrochemical study.

  15. N-(3-Methylphenylquinoxalin-2-amine monohydrate

    Directory of Open Access Journals (Sweden)

    Azila Idris

    2010-09-01

    Full Text Available The quinoxaline system in the title hydrate, C15H13N3·H2O, is roughly planar, the r.m.s. deviation for the 18 non-H atoms being 0.188 Å; this conformation features a short intramolecular C—H...N(pyrazine interaction. In the crystal, the amine H atom forms an N—H...O hydrogen bond to the water molecule, which in turn forms two O—H...N hydrogen bonds to the pyrazine N atoms of different organic molecules. These interactions lead to supramolecular arrays in the bc plane that are two molecules thick; additional π–π interactions stabilize the layers [ring centroid–centroid distance = 3.5923 (7 Å]. The layers stack along the a-axis direction via C—H...π contacts.

  16. Amine scrubbing for CO2 capture.

    Science.gov (United States)

    Rochelle, Gary T

    2009-09-25

    Amine scrubbing has been used to separate carbon dioxide (CO2) from natural gas and hydrogen since 1930. It is a robust technology and is ready to be tested and used on a larger scale for CO2 capture from coal-fired power plants. The minimum work requirement to separate CO2 from coal-fired flue gas and compress CO2 to 150 bar is 0.11 megawatt-hours per metric ton of CO2. Process and solvent improvements should reduce the energy consumption to 0.2 megawatt-hour per ton of CO2. Other advanced technologies will not provide energy-efficient or timely solutions to CO2 emission from conventional coal-fired power plants.

  17. Whole cell biotransformation for reductive amination reactions

    Science.gov (United States)

    Klatte, Stephanie; Lorenz, Elisabeth; Wendisch, Volker F

    2014-01-01

    Whole cell biotransformation systems with enzyme cascading increasingly find application in biocatalysis to complement or replace established chemical synthetic routes for production of, e.g., fine chemicals. Recently, we established an Escherichia coli whole cell biotransformation system for reductive amination by coupling a transaminase and an amino acid dehydrogenase with glucose catabolism for cofactor recycling. Transformation of 2-keto-3-methylvalerate to l-isoleucine by E. coli cells was improved by genetic engineering of glucose metabolism for improved cofactor regeneration. Here, we compare this system with different strategies for cofactor regeneration such as cascading with alcohol dehydrogenases, with alternative production hosts such as Pseudomonas species or Corynebacterium glutamicum, and with improving whole cell biotransformation systems by metabolic engineering of NADPH regeneration. PMID:24406456

  18. Water-soluble primary amine compounds in rural continental precipitation

    Science.gov (United States)

    Gorzelska, Krystyna; Galloway, James N.; Watterson, Karen; Keene, William C.

    Procedures for collecting, storing and analysing precipitation samples for organic nitrogen studies were developed. These procedures preserve chemical integrities of the species of interest, allow for up to 3 months storage and quantitative determination of water-soluble primary amine compounds, with the overall error at the 2 nM detection limit of less than 30%. This methodology was applied to study amino compounds in precipitation samples collected over a period of one year in central Virginia. Nitrogen concentrations of 13 amino acids and 3 aliphatic amines were summed to calculate the total amine nitrogen (TAN). The concentration of TAN ranged from below our detection level to 6658 nM, and possibly reflected a seasonal variation in the source strength of the atmospheric amines. Overall, the most commonly occurring amino compounds were methyl amine, ethyl amine, glutamic acid, glycine and serine. On average, the highest overall contribution to the TAN came from arginine, asparagine, glutamine, methyl amine, serine and alanine. However, large qualitative and quantitative variations observed among samples warrant caution in interpretation and application of the averaged values. TAN in Charlottesville precipitation contributed from less than 1 to ca 10% of the ammonium nitrogen level. However, our estimates show that amino compounds may contribute significantly to reduced nitrogen budget in precipitation in remote regions.

  19. BIOGENIC AMINES CONTENT IN SELECTED WINES DURING WINEMAKING

    Directory of Open Access Journals (Sweden)

    Radka Flasarová

    2012-02-01

    Full Text Available The aim of this study was to describe the development of selected biogenic amines (histamine; tyramine; phenylethylamine; putrescine; agmatine; and cadaverine during the winemaking in 10 selected species grown in Central Europe in 2008. The analysis was performed using ion-exchange chromatography by the sodium-citrate buffers with the post-column ninhydrin derivatization and photometric detection. A comparison of the content of biogenic amines in red and wine varieties showed that red wines have higher concentrations of biogenic amines.

  20. Comparison of Solvation Effects on CO2 Capture with Aqueous Amine Solutions and Amine-Functionalized Ionic Liquids.

    Science.gov (United States)

    Yamada, Hidetaka

    2016-10-13

    Amines are the most widely utilized chemicals for postcombustion CO2 capture, because the reversible reactions between amines and CO2 through their moderate interaction allow effective "catch and release". Usually, CO2 is dissolved in the form of an anion such as carbamate or bicarbonate. Therefore, the reaction energy diagram is potentially governed to a large extent by the polarity of the surrounding solvent. Herein, we compared aqueous amine solutions and amine-functionalized ionic liquids by investigating their dielectric constants and performing an intrinsic reaction coordinate analysis of the CO2 absorption process. Quantum mechanical calculations at the CCSD(T)/6-311++G(d,p)//B3LYP/6-311++G(d,p) level within the continuum solvation model (SMD/IEF-PCM) revealed contrasting dependencies of C-N bond formation on the dielectric constant in those solutions. Amines react with CO2 on an energy surface that is significantly affected by the dielectric constant in conventional aqueous amine solutions, whereas amine-functionalized anions and CO2 form stable C-N bonds with a comparatively lower activation energy regardless of the dielectric constant.

  1. Biogenic amines in italian pecorino cheese.

    Science.gov (United States)

    Schirone, Maria; Tofalo, Rosanna; Visciano, Pierina; Corsetti, Aldo; Suzzi, Giovanna

    2012-01-01

    The quality of distinctive artisanal cheeses is closely associated with the territory of production and its traditions. Pedoclimatic characteristics, genetic autochthonous variations, and anthropic components create an environment so specific that it would be extremely difficult to reproduce elsewhere. Pecorino cheese is included in this sector of the market and is widely diffused in Italy (∼62.000t of production in 2010). Pecorino is a common name given to indicate Italian cheeses made exclusively from pure ewes' milk characterized by a high content of fat matter and it is mainly produced in the middle and south of Italy by traditional procedures from raw or pasteurized milk. The microbiota plays a major role in the development of the organoleptic characteristics of the cheese but it can also be responsible for the accumulation of undesirable substances, such as biogenic amines (BA). Bacterial amino acid decarboxylase activity and BA content have to be investigated within the complex microbial community of raw milk cheese for different cheese technologies. The results emphasize the necessity of controlling the indigenous bacterial population responsible for high production of BA and the use of competitive adjunct cultures could be suggested. Several factors can contribute to the qualitative and quantitative profiles of BA's in Pecorino cheese such as environmental hygienic conditions, pH, salt concentration, water activity, fat content, pasteurization of milk, decarboxylase microorganisms, starter cultures, temperature and time of ripening, storage, part of the cheese (core, edge), and the presence of cofactor (pyridoxal phosphate, availability of aminases and deaminases). In fact physico-chemical parameters seem to favor biogenic amine-positive microbiota; both of these environmental factors can easily be modulated, in order to control growth of undesirable microorganisms. Generally, the total content of BA's in Pecorino cheeses can range from about 100-2400

  2. Study on the Reaction of Benzimidazolium Salt with Amine Compounds

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The addition-hydrolysis reaction of benzimidazolium salt with some mono- andbifunctional amine nucleophiles is reported, and a novel method of biomimetic synthesis forformamides and heterocycle compounds is provided.

  3. Biogenic amines in meat and fermented meat products

    Directory of Open Access Journals (Sweden)

    Joanna Stadnik

    2010-09-01

    Full Text Available Recent trends in food quality and safety promote an increasing search for trace compounds that can affect human health. Biogenic amines belong to this group of substances. They can cause distinctive pharmacological, physiological and toxic effects in organisms. Their amounts are usually increasing as a consequence of the use of poor quality raw materials, during controlled or spontaneous microbial fermentation or in the course of food spoilage. The origin of biogenic amines makes them suitable as chemical indicators of the hygienic quality and freshness of some foods being associated to the degree of food fermentation or degradation. The development of appropriate manufacturing technologies to obtain products free or nearly free from biogenic amines is a challenge for the meat industry. This review briefly summarises current knowledge on the biological implications of biogenic amines on human health and collects data on the factors affecting their formation in meat and fermented meat products.

  4. FTIR Study of Enhanced Polymeric Blend Membrane with Amines

    Directory of Open Access Journals (Sweden)

    Asim Mushtaq

    2014-03-01

    Full Text Available In this study, research will be carried out to identify the functional group behavior of glassy and rubbery polymeric blend membrane with amines. Polymeric blend membranes with different blending ratios were prepared and the developed membranes were characterized by FTIR to see the effect of blend ratio on different functional groups. The developed membranes are flat dense sheet membrane of 20% wt/wt. The pure and blend membrane polysulfone, polyethersulfone, polyvinyl acetate with different composition, with 10% methyl diethanol amine, mono ethanol amine, diethanol amine are developed with dimethyl acetamide solvent. Fourier Transform Infrared (FTIR spectroscopy was utilized to study the interaction between two polymers and to analyze the type of bonding present. To observed frequencies were assigned to various mode of vibration in terms of fundamentals and combination. These spectral changes indicated the existence of molecular interaction among the enhanced polymeric blends; highlight the compatible nature among each other.

  5. Two simple amine hydrochlorides from the soft coral Lobophytum strictum

    Digital Repository Service at National Institute of Oceanography (India)

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

    Two simple amine hydrochlorides, viz., 1-amino-1, 1-dimethyl-3-oxo-butane hydrochloride (1) (Diacetonamine) and 2, 2, 6, 6-tetramethylpiperidone hydrochloride (2) have been isolated from the fraction of the methanolic extract of the soft coral...

  6. Amine reclaiming technologies in post-combustion carbon dioxide capture.

    Science.gov (United States)

    Wang, Tielin; Hovland, Jon; Jens, Klaus J

    2015-01-01

    Amine scrubbing is the most developed technology for carbon dioxide (CO2) capture. Degradation of amine solvents due to the presence of high levels of oxygen and other impurities in flue gas causes increasing costs and deterioration in long term performance, and therefore purification of the solvents is needed to overcome these problems. This review presents the reclaiming of amine solvents used for post combustion CO2 capture (PCC). Thermal reclaiming, ion exchange, and electrodialysis, although principally developed for sour gas sweetening, have also been tested for CO2 capture from flue gas. The three technologies all have their strengths and weaknesses, and further development is needed to reduce energy usage and costs. An expected future trend for amine reclamation is to focus on process integration of the current reclaiming technologies into the PCC process in order to drive down costs.

  7. Silver-catalyzed synthesis of amides from amines and aldehydes

    Science.gov (United States)

    Madix, Robert J; Zhou, Ling; Xu, Bingjun; Friend, Cynthia M; Freyschlag, Cassandra G

    2014-11-18

    The invention provides a method for producing amides via the reaction of aldehydes and amines with oxygen adsorbed on a metallic silver or silver alloy catalyst. An exemplary reaction is shown in Scheme 1: (I), (II), (III). ##STR00001##

  8. Amine reclaiming technologies in post-combustion carbon dioxide capture

    Institute of Scientific and Technical Information of China (English)

    Tielin Wang; Jon Hovland; KlauS J.Jens

    2015-01-01

    Amine scrubbing is the most developed technology for carbon dioxide (CO2) capture.Degradation of amine solvents due to the presence of high levels of oxygen and other impurities in flue gas causes increasing costs and deterioration in long term performance,and therefore purification of the solvents is needed to overcome these problems.This review presents the reclaiming of amine solvents used for post combustion CO2 capture (PCC).Thermal reclaiming,ion exchange,and electrodialysis,although principally developed for sour gas sweetening,have also been tested for CO2 capture from flue gas.The three technologies all have their strengths and weaknesses,and further development is needed to reduce energy usage and costs.An expected future trend for amine reclamation is to focus on process integration of the current reclaiming technologies into the PCC process in order to drive down costs.

  9. Isomerization of metastable amine radical cations by dissociation-recombination

    DEFF Research Database (Denmark)

    Pedersen, Anders Holmen; Nielsen, Christian Benedikt; Bojesen, Gustav;

    2015-01-01

    The metastable molecular ions of primary aliphatic amines branched at C2 can isomerize by cleavage-recombination, thereby facilitating fragmentation reactions that require less energy than simple cleavage of the initial molecular ion. This process complements the reactions described by Audier...... to account for the conspicuous absence of the conventional a-cleavage among the major fragmentation reactions of the metastable molecular ions of primary amines....

  10. Cloud condensation nuclei (CCN) activity of aliphatic amine secondary aerosol

    Science.gov (United States)

    Tang, X.; Price, D.; Praske, E.; Vu, D. N.; Purvis-Roberts, K.; Silva, P. J.; Cocker, D. R., III; Asa-Awuku, A.

    2014-06-01

    Aliphatic amines can form secondary aerosol via oxidation with atmospheric radicals (e.g., hydroxyl radical and nitrate radical). The particle can contain both secondary organic aerosol (SOA) and inorganic salts. The ratio of organic to inorganic materials in the particulate phase influences aerosol hygroscopicity and cloud condensation nuclei (CCN) activity. SOA formed from trimethylamine (TMA) and butylamine (BA) reactions with hydroxyl radical (OH) is composed of organic material of low hygroscopicity (single hygroscopicity parameter, κ, ≤ 0.25). Secondary aerosol formed from the tertiary aliphatic amine (TMA) with N2O5 (source of nitrate radical, NO3) contains less volatile compounds than the primary aliphatic amine (BA) aerosol. As relative humidity (RH) increases, inorganic amine salts are formed as a result of acid-base reactions. The CCN activity of the humid TMA-N2O5 aerosol obeys Zdanovskii, Stokes, and Robinson (ZSR) ideal mixing rules. The humid BA + N2O5 aerosol products were found to be very sensitive to the temperature at which the measurements were made within the streamwise continuous-flow thermal gradient CCN counter; κ ranges from 0.4 to 0.7 dependent on the instrument supersaturation (ss) settings. The variance of the measured aerosol κ values indicates that simple ZSR rules cannot be applied to the CCN results from the primary aliphatic amine system. Overall, aliphatic amine aerosol systems' κ ranges within 0.2 systems.

  11. Biogenic amines in wines from three Spanish regions.

    Science.gov (United States)

    Landete, José M; Ferrer, Sergi; Polo, Lucía; Pardo, Isabel

    2005-02-23

    One hundred and sixty-three wines from La Rioja, Utiel-Requena, and Tarragona were analyzed to determine if there were any differences in the concentrations of six biogenic amines that are found in these three regions. The influence of grape variety, type of vinification, wine pH, malolactic fermentation, and storage in bottle on biogenic amine concentrations was studied. Results show important differences in putrescine and histamine concentrations among regions, varieties of grape, and type of wine; differences were less appreciable for the remaining biogenic amines studied. Low pH prevented biogenic amine formation. Malolactic fermentation and short storage periods in bottle (3-6 months) showed increases in histamine concentration, whereas longer periods of storage led to a general decrease in histamine. Several strains of lactic acid bacteria were isolated in this work, and their ability to form biogenic amines was assayed in synthetic media, grape must, and wine. Grape varieties, different types of winemaking, pH, and lactic acid bacteria may be responsible for the differences observed in the biogenic amine concentrations of the wines analyzed.

  12. STRUCTURAL EFFECT ON VINYL POLYMERIZATION INITIATED WITH AROMATIC TERTIARY AMINE

    Institute of Scientific and Technical Information of China (English)

    CAO Weixiao; FENG Xinde

    1983-01-01

    The polymerization mechanism of various vinyl monomers in the presence of aromatic tertiary amines has been studied. It was found that the mechanisms of different monomers are varied with the structures of monomers. Those monomers, such as methacrylic esters containing α-CH3 group on the double bond could be polymerized with aromatic tertiary amine in the absence of light,while the monomers without α-CH3 group, such as methyl acrylate, acrylonitrile etc. would polymerize only under light.The structural effects, both of the monomer and the amine, on the rate of photopolymerization were studied. The activities of monomers and amines may be arranged in the following orderMonomer: AN>MA>VA>St Amine: DMT>DMA>DMB>DNAIt is revealed that both the electro-negative group on the double bond of monomer which acts as an acceptor and the electro-positive group on the nitrogen atom of amine which acts as a donor would effectively increase the rate of photopolymerization.

  13. STUDIES ON VINYL POLYMERIZATION WITH INITIATION SYSTEM CONTAINING AMINE DERIVATIVES

    Institute of Scientific and Technical Information of China (English)

    QIU Kunyuan; ZHANG Jingyi; FENG Xinde(S. T. Voong)

    1983-01-01

    Two main types of amine-containing initiation systems were studied in this work. In the case of MMA polymerization initiated by BPO-amine (DMT, DHET, DMA) redox systems, it was found that the polymerization rate and colour stability of the polymer for different amine systems were in the following order: DMT≈DHET>DMA. Accordingly, BPO-DMT and BPO-DHET are effective initiators. In the case of MEMA polymerization by amine (DMT, DHET, DMA) alone, it was found that the polymerization rate and the percentage of conversion for these different amine systems were in the following order: DMT≥DHET>DMA. The polymerization rate and the percentage of conversion also increased with the increase of DMT concentration. From the kinetic investigation the rate equation of Rp=K [DMT]1/2 [MEMA]3/2 was obtained, and the overall activation energy of polymerization was calculated to be 34.3 KJ/mol (8.2 Kcal/mol). Moreover, the polymerization of MEMA in the presence of DMT was strongly inhibited by hydroquinone, indicating the polymerization being free radical in nature. From these results, the mechanism of MEMA polymerization initiated by amine was proposed.

  14. Amine-functionalized porous silicas as adsorbents for aldehyde abatement.

    Science.gov (United States)

    Nomura, Akihiro; Jones, Christopher W

    2013-06-26

    A series of aminopropyl-functionalized silicas containing of primary, secondary, or tertiary amines is fabricated via silane-grafting on mesoporous SBA-15 silica and the utility of each material in the adsorption of volatile aldehydes from air is systematically assessed. A particular emphasis is placed on low-molecular-weight aldehydes such as formaldehyde and acetaldehyde, which are highly problematic volatile organic compound (VOC) pollutants. The adsorption tests demonstrate that the aminosilica materials with primary amines most effectively adsorbed formaldehyde with an adsorption capacity of 1.4 mmolHCHO g(-1), whereas the aminosilica containing secondary amines showed lower adsorption capacity (0.80 mmolHCHO g(-1)) and the aminosilica containing tertiary amines adsorbed a negligible amount of formaldehyde. The primary amine containing silica also successfully abated higher aldehyde VOC pollutants, including acetaldehyde, hexanal, and benzaldehyde, by effectively adsorbing them. The adsorption mechanism is investigated by (13)C CP MAS solid-state NMR and FT-Raman spectroscopy, and it is demonstrated that the aldehydes are chemically attached to the surface of aminosilica in the form of imines and hemiaminals. The high aldehyde adsorption capacities of the primary aminosilicas in this study demonstrate the utility of amine-functionalized silica materials for reduction of gaseous aldehydes.

  15. Heterocyclic amines in meat and meat products

    Directory of Open Access Journals (Sweden)

    Aliye BULGAN

    2013-06-01

    Full Text Available Heterocyclic amines (HA are the mutagenic/carcinogenic compounds which generate as a result of cooking of red meat, poultry meat and fish fillets at high temperatures. Up to 20 different HAs were detected and classified in the researches that conducted on these types of meats cooked at high temperatures. HAs are the products of Maillard reactions and the Strecker degredation of main precursors such as creatine/creatinine, aminoacid and the polysaccharides. Many physical and chemical factors effect the formation of HAs. Thus, it was reported by many researchers that utilizing coating and marination processes in addition to using natural and synthetic antioxidants and seasonings-plant extracts were effective on inhibiting/decreasing the formation of HAs. Additionally, boiling/steaming and microwave cooking methodologies were recommended instead of barbecuing, grilling or frying to inhibit/decrease the formation of HAs. The HAs formed in meat and meat products and the factors which have effects on the formation of HAs are presented in this review.

  16. ANTIMICROBIAL POTENT OXAZINE-2-AMINE DERIVATIVES

    Directory of Open Access Journals (Sweden)

    GANESAMOORTHY THIRUNARAYANAN

    2016-07-01

    Full Text Available Objective: To synthesize thirteen effective microbial potent oxazine-2-amine derivatives and evaluate the antimicrobial activities of these compounds. Material and methods: The solvent-free solid fly-ash: H2SO4 catalyzed cyclization of 4-bromo-1-naphthyl chalcones and urea under microwave irradiation technique was utilized for the synthesis of oxazine derivatives. The synthesized oxazines were characterized by their physical constants and spectroscopic data. The Bauer-Kirby disc-diffusion method of measurement of zone of inhibition was used for evaluation antimicrobial activity of synthesized oxazines. Results: The cyclization was effective and this reaction gave more than 80% yield. The catalyst was reused up to five times consecutively without appreciable decreasing of yield. All compounds were active against their microbial strains. Conclusions: This solvent-free synthetic method was effective for the synthesis of oxazine derivatives. The amino, dimethylamino, halogens, methoxy and methyl substituted oxazines shows significant antibacterial activity. Chloro, hydroxy and nitro substituted oxazine derivative have shown significant antifungal activity.

  17. Dynamic Kinetic Asymmetric Amination of Alcohols: From A Mixture of Four Isomers to Diastereo- and Enantiopure α-Branched Amines.

    Science.gov (United States)

    Rong, Zi-Qiang; Zhang, Yao; Chua, Raymond Hong Bing; Pan, Hui-Jie; Zhao, Yu

    2015-04-22

    The first dynamic kinetic asymmetric amination of alcohols via borrowing hydrogen methodology is presented. Under the cooperative catalysis by an iridium complex and a chiral phosphoric acid, α-branched alcohols that exist as a mixture of four isomers undergo racemization by two orthogonal mechanisms and are converted to diastereo- and enantiopure amines bearing adjacent stereocenters. The preparation of diastereo- and enantiopure 1,2-amino alcohols is also realized using this catalytic system.

  18. Preparation of tertiary amines by the reaction of iminium ions derived from unsymmetrical aminals with zinc and magnesium organometallics.

    Science.gov (United States)

    Werner, Veronika; Ellwart, Mario; Wagner, Andreas J; Knochel, Paul

    2015-04-17

    We report a convenient one-pot preparation of polyfunctional tertiary amines, including various biorelevant phenethylamines or ephedrine derivatives, via the reaction of new functionalized iminium ions with a variety of zinc and magnesium organometallic reagents. These iminium ions were generated from unsymmetrical aminals, obtained by the in situ addition of various amides to Tietze's iminium salt [Me2NCH2(+)CF3COO(-)]. A functionalized aniline, prepared by this method, was converted to a quinolidine via an intramolecular Heck reaction.

  19. Biogenic amines in Italian Pecorino cheese

    Directory of Open Access Journals (Sweden)

    Maria eSchirone

    2012-05-01

    Full Text Available The quality of distinctive artisanal cheeses is closely associated with the territory of production and its traditions. Pedoclimatic characteristics, genetic autochthonous variations and anthropic components create an environment so specific that it would be extremely difficult to reproduce elsewhere. Pecorino cheese is included in this sector of the market and is widely diffused in Italy (approximately 53.727t of production. Pecorino is a common name given to indicate Italian cheeses made exclusively from pure ewes' milk characterized by a high content of fat matter and it is mainly produced in the middle and south of Italy by traditional procedures from raw or thermized milk. The microbiota plays a major role in the development of the organoleptic characteristics of the cheese but it can also be responsible for the accumulation of undesirable substances, such as biogenic amines (BA. Several factors can contribute to the qualitative and quantitative profiles of BA’s in Pecorino cheese such as environmental hygienic conditions, pH, salt concentration, aw, fat content, pasteurization of milk, decarboxylase microorganisms, starter cultures, temperature and time of ripening, storage, part of the cheese (core, edge and the presence of cofactor. Generally, the total content of BA’s can range from about 100-2400 mg/kg, with a prevalence of toxicologically important BA’s, tyramine and histamine. The presence of BA in Pecorino cheeses is becoming increasingly important to consumers and cheese-maker alike, due to the potential threats of toxicity to humans and consequent trade implications.

  20. The ozonolysis of primary aliphatic amines in fine particles

    Directory of Open Access Journals (Sweden)

    J. Zahardis

    2008-02-01

    Full Text Available The oxidative processing by ozone of the particulate amines octadecylamine (ODA and hexadecylamine (HDA is reported. Ozonolysis of these amines resulted in strong NO2 and NO3 ion signals that increased with ozone exposure as monitored by photoelectron resonance capture ionization aerosol mass spectrometry. These products suggest a mechanism of progressive oxidation of the particulate amines to nitroalkanes. Additionally, a strong ion signal at 125 m/z is assigned to the ion NO3 (HNO3. For ozonized mixed particles containing ODA or HDA + oleic acid (OL, with pO3≥3×10–7 atm, imine, secondary amide, and tertiary amide products were measured. These products most likely arise from reactions of amines with aldehydes (for imines and stabilized Criegee intermediates (SCI or secondary ozonides (for amides from the fatty acid. The routes to amides via SCI and/or secondary ozonides were shown to be more important than comparable amide forming reactions between amines and organic acids, using azelaic acid as a test compound. Finally, direct evidence is provided for the formation of a surface barrier in the ODA + OL reaction system that resulted in the retention of OL at high ozone exposures (up to 10−3 atm for 17 s. This effect was not observed in HDA + OL or single component OL particles, suggesting that it may be a species-specific surfactant effect from an in situ generated amide or imine. Implications to tropospheric chemistry, including particle bound amines as sources of oxidized gas phase nitrogen species (e.g.~NO2, NO3, formation of nitrogen enriched HULIS via ozonolysis of amines and source apportionment are discussed.

  1. Secondary aerosol formation from atmospheric reactions of aliphatic amines

    Directory of Open Access Journals (Sweden)

    S. M. Murphy

    2007-01-01

    Full Text Available Although aliphatic amines have been detected in both urban and rural atmospheric aerosols, little is known about the chemistry leading to particle formation or the potential aerosol yields from reactions of gas-phase amines. We present here the first systematic study of aerosol formation from the atmospheric reactions of amines. Based on laboratory chamber experiments and theoretical calculations, we evaluate aerosol formation from reaction of OH, ozone, and nitric acid with trimethylamine, methylamine, triethylamine, diethylamine, ethylamine, and ethanolamine. Entropies of formation for alkylammonium nitrate salts are estimated by molecular dynamics calculations enabling us to estimate equilibrium constants for the reactions of amines with nitric acid. Though subject to significant uncertainty, the calculated dissociation equilibrium constant for diethylammonium nitrate is found to be sufficiently small to allow for its atmospheric formation, even in the presence of ammonia which competes for available nitric acid. Experimental chamber studies indicate that the dissociation equilibrium constant for triethylammonium nitrate is of the same order of magnitude as that for ammonium nitrate. All amines studied form aerosol when photooxidized in the presence of NOx with the majority of the aerosol mass present at the peak of aerosol growth consisting of aminium (R3NH+ nitrate salts, which repartition back to the gas phase as the parent amine is consumed. Only the two tertiary amines studied, trimethylamine and triethylamine, are found to form significant non-salt organic aerosol when oxidized by OH or ozone; calculated organic mass yields for the experiments conducted are similar for ozonolysis (15% and 5% respectively and photooxidation (23% and 8% respectively. The non-salt organic aerosol formed appears to be more stable than the nitrate salts and does not quickly repartition back to the gas phase.

  2. Secondary aerosol formation from atmospheric reactions of aliphatic amines

    Directory of Open Access Journals (Sweden)

    S. M. Murphy

    2007-01-01

    Full Text Available Although aliphatic amines have been detected in both urban and rural atmospheric aerosols, little is known about the chemistry leading to particle formation or the potential aerosol yields from reactions of gas-phase amines. We present here the first systematic study of aerosol formation from the atmospheric reactions of amines. Based on laboratory chamber experiments and theoretical calculations, we evaluate aerosol formation from reaction of OH, ozone, and nitric acid with trimethylamine, methylamine, triethylamine, diethylamine, ethylamine, and ethanolamine. Entropies of formation for alkylammonium nitrate salts are estimated by molecular dynamics calculations enabling us to estimate equilibrium constants for the reactions of amines with nitric acid. Though subject to significant uncertainty, the calculated dissociation equilibrium constant for diethylammonium nitrate is found to be sufficiently small to allow for its atmospheric formation, even in the presence of ammonia which competes for available nitric acid. Experimental chamber studies indicate that the dissociation equilibrium constant for triethylammonium nitrate is of the same order of magnitude as that for ammonium nitrate. All amines studied form aerosol when photooxidized in the presence of NOx with the majority of the aerosol mass present at the peak of aerosol growth consisting of aminium (R3NH+ nitrate salts, which repartition back to the gas phase as the parent amine is consumed. Only the two tertiary amines studied, trimethylamine and triethylamine, are found to form significant non-salt organic aerosol when oxidized by OH or ozone; calculated organic mass yields for the experiments conducted are similar for ozonolysis (15% and 5% respectively and photooxidation (23% and 8% respectively. The non-salt organic aerosol formed appears to be more stable than the nitrate salts and does not quickly repartition back to the gas phase.

  3. Mutagenic activity and heterocyclic amine content of the human diet

    Energy Technology Data Exchange (ETDEWEB)

    Knize, M.G.; Dolbeare, F.A.; Cunningham, P.L.; Felton, J.S.

    1993-01-15

    The mutagenic activity and the mass amount of heterocyclic amines responsible for the mutagenic activity have been measured in some cooked foods. Cooked meats are the predominant source of mutagenic activity in the diet with values ranging from 0 to 10,000 revertants per gram reported in the Ames/Salmonelia test with strain TA98. Several heterocyclic amines are present and have been quantified using solid-phase extraction followed by HPLC. Frying at higher temperatures and for longer times produces the greatest mutagenic response, and concomitantly, the largest amounts of heterocyclic amines. Most of the mutagenic activity in fried meat samples can be accounted for by MelQx, DiMelQx and IQ, although other heterocylic amines are present and PHIP mutagenic activity becomes significant at higher temperatures. Non-meat products such as baked breads can also form significant mutagenic activity, particularly when overcooked. Commercially prepared hamburgers made from meat substitutes such as tofu, wheat gluten or tempeh and fried at 210{degrees}C have up to 10% of the mutagenic activity of a fried beef patty cooked under the same conditions. When detected, amounts of heterocyclic amines in fried beef patties range from a total of 0.35 ng/g for commercial beef hamburgers to 142 ng/g for a beef patty cooked over a barbecue. Dietary intake is expected to have a large range, from less than one microgram per day to over 50 micrograms per day based on current knowledge of known heterocyclic amine chemicals and heterocyclic amine-containing foods.

  4. Biogenic amines at a low level of evolution: Production, functions and regulation in the unicellular Tetrahymena.

    Science.gov (United States)

    Csaba, György

    2015-06-01

    The unicellular eukaryote Tetrahymena synthesize, store and secrete biogenic amines (histamine, serotonin, epinephrine, dopamine, melatonin) and also can take up amines from the milieu. It also has (G-protein-coupled) receptors (binding sites) for these amines as well, as second messengers. The factors infuencing the mentioned processes are shown. For certain amines the genes and the coded enzymes are demonstrated. The amines influence phagocytosis, cell division, ciliary regeneration, glucose metabolism and chemotaxis. There are interhormone actions between the amines, and between the amines and other hormones produced by Tetrahymena. The critical review discusses the role of amines in the early stages of evolution and compares this to their functions in mammals. It tries to give answer how and why biogenic amines were selected to hormones, and why new functions formed for them in higher ranked animals, preserving also the ancient ones.

  5. Polycyclic amines as chloroquine resistance modulating agents in Plasmodium falciparum.

    Science.gov (United States)

    Joubert, Jacques; Kapp, Erika; Taylor, Dale; Smith, Peter J; Malan, Sarel F

    2016-02-15

    Pentacycloundecylamines (PCUs) and adamantane amines, such as NGP1-01 (1) and amantadine, have shown significant channel blocking activities. They are postulated to act as chemosensitizers and circumvent the resistance of the plasmodia parasite against chloroquine (CQ) by inhibiting the p-glycoprotein efflux pump and enabling the accumulation of CQ inside the parasite digestive vacuole. Twelve polycyclic amines containing either a PCU or adamantane amine moiety conjugated to different aromatic functionalities through various tethered linkers were selected based on their channel blocking abilities and evaluated as potential chemosensitizers. Compounds 2, 4, 5 and 10 showed significant voltage-gated calcium channel (VGCC) blocking ability (IC50=0.27-35 μM) and were able to alter the CQ IC50 in differing degrees (45-81%) in the multidrug resistant Plasmodium falciparum Dd2 isolate. Among them, the PCU-dansyl amine compound (4) displayed the best potential to act as a chemosensitizer against the Dd2 strain at a 1 μM concentration (RMI=0.19) while displaying moderate antiplasmodial activity (Dd2 IC50=6.25 μM) and low in vitro cytotoxicity against a mammalian cell line (CHO, IC50=119 μM). Compounds 2 and 10 also showed some promising chemosensitizing abilities (RMI=0.36 and 0.35 respectively). A direct correlation was found between the VGCC blocking ability of these polycyclic amines and their capacity to act as CQ resistance modulating agents.

  6. Choosing amine-based absorbents for CO2 capture.

    Science.gov (United States)

    Gomes, João; Santos, Samuel; Bordado, João

    2015-01-01

    CO2 capture from gaseous effluents is one of the great challenges faced by chemical and environmental engineers, as the increase in CO2 levels in the Earth atmosphere might be responsible for dramatic climate changes. From the existing capture technologies, the only proven and mature technology is chemical absorption using aqueous amine solutions. However, bearing in mind that this process is somewhat expensive, it is important to choose the most efficient and, at the same time, the least expensive solvents. For this purpose, a pilot test facility was assembled and includes an absorption column, as well as a stripping column, a heat exchanger between the two columns, a reboiler for the stripping column, pumping systems, surge tanks and all necessary instrumentation and control systems. Some different aquous amine solutions were tested on this facility and it was found that, from a set of six tested amines, diethanol amine is the one that turned out to be the most economical choice, as it showed a higher CO2 loading capacity (0.982 mol of CO2 per mol of amine) and the lowest price per litre (25.70 €/L), even when compared with monoethanolamine, the benchmark solvent, exhibiting a price per litre of 30.50 €/L.

  7. Blue Chitin columns for the extraction of heterocyclic amines from urine samples

    DEFF Research Database (Denmark)

    Bang, J.; Frandsen, Henrik Lauritz; Skog, K.

    2004-01-01

    During normal cooking of meat, a class of mutagenic/carcinogenic compounds called heterocyclic amines is formed. Heterocyclic amines are rapidly absorbed and metabolised in the human body, and for estimation of the intake of heterocyclic amines, it is useful to determinate their levels in the urine....... Blue Chitin columns were used for the extraction and purification of heterocyclic amines from urine samples spiked with 14 different heterocyclic amines. The samples were analysed using LC-MS. The results show that Blue Chitin columns provide a straightforward and rapid means of extracting heterocyclic...... amines from urine samples, and that Blue Chitin column are also useful in the purification of urinary metabolites....

  8. The Potential of the Yeast Debaryomyces hansenii H525 to Degrade Biogenic Amines in Food

    Directory of Open Access Journals (Sweden)

    Mathias Bäumlisberger

    2015-11-01

    Full Text Available Twenty-six yeasts from different genera were investigated for their ability to metabolize biogenic amines. About half of the yeast strains produced one or more different biogenic amines, but some strains of Debaryomyces hansenii and Yarrowia lipolytica were also able to degrade such compounds. The most effective strain D. hanseniii H525 metabolized a broad spectrum of biogenic amines by growing and resting cells. Degradation of biogenic amines by this yeast isolate could be attributed to a peroxisomal amine oxidase activity. Strain H525 may be useful as a starter culture to reduce biogenic amines in fermented food.

  9. New amines for the reversible absorption of carbon dioxide from gas mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Michele Aresta; Angela Dibenedetto [University of Bari, Bari (Italy). Department of Chemistry and METEA Research Center

    2003-07-01

    This paper discusses the use of new amines as a medium for the capture of CO{sub 2} from a gas mixture. The study was carried out comparing the absorption of carbon dioxide by two alkyl-di-amines with that of amines used so far at industrial level, namely mono-ethanolamine (MEA). A known mono silyl-alkyl-amine was also studied for comparison. The absorption of carbon dioxide was studied at different temperatures, in water solution, in organic solvents and using the neat amine. Several cycles of absorption/desorption were carried out. Xerogel solidified amines were also used. 12 refs., 6 figs.

  10. A Metal and Base-Free Chemoselective Primary Amination of Boronic Acids Using Cyanamidyl/Arylcyanamidyl Radical as Aminating Species: Synthesis and Mechanistic Studies by Density Functional Theory.

    Science.gov (United States)

    Chatterjee, Nachiketa; Arfeen, Minhajul; Bharatam, Prasad V; Goswami, Avijit

    2016-06-17

    An efficient, metal and base-free, chemoselective synthesis of aryl-, heteroaryl-, and alkyl primary amines from the corresponding boronic acids has been achieved at ambient temperature mediated by [bis(trifluoroacetoxy)iodo]benzene (PIFA) and N-bromosuccinimide (NBS) using cyanamidyl/arylcyanamidyl radicals as the aminating species. The primary amine compounds were initially obtained as their corresponding ammonium trifluoroacetate salts which, on treatment with aq NaOH, provide the free amines. Finally, the primary amines were isolated through column chromatography over silica-gel using hexane-EtOAc solvent system as the eluent. The reactions are sufficiently fast, completing within 1 h. Quantum chemical calculations in combination with experimental observations validate that the ipso amination of substituted boronic acids involves the formation of cyanamidyl/arylcyanamidyl radical, followed by regiospecific interaction of its nitrile-N center with boron atom of the boronic acids, leading to chemoselective primary amination.

  11. Relationship between analgesia and turnover of brain biogenic amines.

    Science.gov (United States)

    Bensemana, D; Gascon, A L

    1978-10-01

    The analgesic activity of morphine, delta9THC, and sodium salicylate was studied concomitantly with changes in brainstem and cortex turnover of dopamine (DA), noradrenaline (NA), and serotonin (5HT). The results show that a correlation exists between the presence of analgesia and the increased turnover rates of the three biogenic amines. Morphine and sodium salicylate induced analgesia is accompanied by an increased turnover rate of all three biogenic amines; delta9THC-induced analgesia is accompanied by an increased turnover rate of DA and 5HT only. There is, however, no consistent relationship between the degree of analgesia and the degree of change in the turnover rates. The existence of the endogenous morphine-like substances, endorphines, may explain why morphine analgesia is distinct from that of delta9THC and sodium salicylate. The possible relationship between this morphine-like substance and biogenic amines is discussed.

  12. Amine modeling for CO2 capture: internals selection.

    Science.gov (United States)

    Karpe, Prakash; Aichele, Clint P

    2013-04-16

    Traditionally, trays have been the mass-transfer device of choice in amine absorption units. However, the need to process large volumes of flue gas to capture CO2 and the resultant high costs of multiple trains of large trayed columns have prompted process licensors and vendors to investigate alternative mass-transfer devices. These alternatives include third-generation random packings and structured packings. Nevertheless, clear-cut guidelines for selection of packings for amine units are lacking. This paper provides well-defined guidelines and a consistent framework for the choice of mass-transfer devices for amine absorbers and regenerators. This work emphasizes the role played by the flow parameter, a measure of column liquid loading and pressure, in the type of packing selected. In addition, this paper demonstrates the significant economic advantage of packings over trays in terms of capital costs (CAPEX) and operating costs (OPEX).

  13. Mechanism of phosphine borane deprotection with amines: the effects of phosphine, solvent and amine on rate and efficiency.

    Science.gov (United States)

    Lloyd-Jones, Guy C; Taylor, Nicholas P

    2015-03-27

    The kinetics of borane transfer from simple tertiary phosphine borane adducts to a wide range of amines have been determined. All data obtained, including second-order kinetics, lack of cross-over, and negative entropies of activation for reaction of triphenylphosphine borane with quinuclidine and triethylamine, are consistent with a direct (SN 2-like) transfer process, rather than a dissociative (SN 1-like) process. The identities of the amine, phosphine, and solvent all impact substantially on the rate (k) and equilibrium (K) of the transfer, which in some cases vary by many orders of magnitude. P-to-N transfer is more efficient with cyclic amines in apolar solvents due to reduced entropic costs and ground-state destabilisation. Taken as a whole, the data allow informed optimisation of the deprotection step from the stand-point of rate, or synthetic convenience. In all cases, both reactants should be present at high initial concentration to gain kinetic benefit from the bimolecularity of the process. Ultimately, the choice of amine is dictated by the identity of the phosphine borane complex. Aryl-rich phosphine boranes are sufficiently reactive to allow use of diethylamine or pyrrolidine as a volatile low polarity solvent and reactant, whereas more alkyl-rich phosphines benefit from the use of more reactive amines, such as 1,4-diaza[2.2.2]bicyclooctane (DABCO), in apolar solvents at higher temperatures.

  14. Skin absorption of six performance amines used in metalworking fluids.

    Science.gov (United States)

    Roux, Lauriane N; Brooks, James D; Yeatts, James L; Baynes, Ronald E

    2015-05-01

    Every year, 10 million workers are exposed to metalworking fluids (MWFs) that may be toxic. There are four types of MWFs: neat oils and three water-based MWFs (soluble oil, semisynthetic and synthetic), which are diluted with water and whose composition varies according to the mineral oils ratio. MWFs also contain various additives. To determine the absorption of six amines used as corrosion inhibitors and biocides in MWFs, porcine skin flow-through diffusion cell experiments were conducted with hydrophilic ethanolamines (mono-, di- and triethanolamine, MEA, DEA and TEA respectively) and a mixture of lipophilic amines (dibutylethanolamine, dicyclohexylamine and diphenylamine). The six amines were dosed in four vehicles (water and three generic water-based MWF formulations) and analyzed using a scintillation counter or gas chromatography/mass spectrometry. These 24 h studies showed that dermal absorption significantly (P < 0.05) increased from water for the six amines (e.g. 1.15 ± 0.29% dose; DEA in water) compared to other formulations (e.g. 0.13 ± 0.01% dose; DEA in semisynthetic MWF) and absorption was greatest for dibutylethanolamine in all the formulations. The soluble oil formulation tended to increase the dermal absorption of the hydrophilic amines. The permeability coefficient was significantly higher (P < 0.05) with TEA relative to the other hydrophilic amines (e.g. 4.22 × 10(-4) ± 0.53 × 10(-4) cm h(-1) [TEA in synthetic MWF] vs. 1.23 × 10(-4) ± 0.10 × 10(-4) cm h(-1) [MEA in synthetic MWF]), except for MEA in soluble oil formulation. Future research will confirm these findings in an in vivo pig model along with dermatotoxicity studies. These results should help MWF industries choose safer additives for their formulations to protect the health of metalworkers.

  15. Amine-intercalated α-zirconium phosphates as lubricant additives

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Huaping; Dai, Wei [Department of Mechanical Engineering, Texas A& M University, College Station, TX 77843 (United States); Kan, Yuwei; Clearfield, Abraham [Department of Chemistry, Texas A& M University, College Station, TX 77843 (United States); Liang, Hong, E-mail: hliang@tamu.edu [Department of Mechanical Engineering, Texas A& M University, College Station, TX 77843 (United States)

    2015-02-28

    In this study, three types of amines intercalated α-zirconium phosphate nanosheets with different interspaces were synthesized and examined as lubricant additives to a mineral oil. Results from tribological experiments illustrated that these additives improved lubricating performance. Results of rheological experiments showed that the viscosity of the mineral oil was effectively reduced with the addition of α-zirconium phosphate nanosheets. The two-dimensional structure, with larger interspaces, resulting from amine intercalation, exhibited improved effectiveness in reducing viscosity. This study demonstrates that the nanosheet structure of α-zirconium phosphates is effective in friction reduction. The manufacture of lubricants with tailored viscosity is possible by using different intercalators.

  16. Mesoporous amine-bridged polysilsesquioxane for CO2 capture

    KAUST Repository

    Qi, Genggeng

    2011-01-01

    A novel class of amine-supported sorbents based on amine-bridged mesoporous polysilsesquioxane was developed via a simple one-pot sol-gel process. The new sorbent allows the incorporation of a large amount of active groups without sacrificing surface area or pore volume available for CO2 capture, leading to a CO2 capture capacity of 3.2 mmol g−1 under simulated flue gas conditions. The sorbent is readily regenerated at 100°C and exhibits good stability over repetitive adsorption-desorption cycling.

  17. Enzymatic network for production of ether amines from alcohols

    DEFF Research Database (Denmark)

    Palacio, Cyntia M.; Crismaru, Ciprian G.; Bartsch, Sebastian

    2016-01-01

    We constructed an enzymatic network composed of three different enzymes for the synthesis of valuable ether amines. The enzymatic reactions are interconnected to catalyze the oxidation and subsequent transamination of the substrate and to provide cofactor recycling. This allows production...... for reactions containing 10mM alcohol and up to 280mM ammonia corresponded well to predicted conversions. The results indicate that efficient amination can be driven by high concentrations of ammonia and may require improving enzyme robustness for scale-up....

  18. Biogenic amines in smear and mould-ripened cheeses

    Directory of Open Access Journals (Sweden)

    Pavel Pleva

    2014-02-01

    Full Text Available The aim of the study was the monitoring of six biogenic amines (histamine, tyramine, phenylethylamine, tryptamine, putrescine, and cadaverine and two polyamines (spermidine and spermine in 30 samples of dairy products purchased in the Czech Republic, namely in 15 samples of mould-ripened cheeses and in 15 samples of smear-ripened cheeses. A further goal was the microbiological analysis of the individual samples of cheeses (total count of microorganisms, number of enterobacteria, enterococci, lactic acid bacteria, yeasts and moulds. The monitored biogenic amines were analyzed by a high performance liquid chromatography equipped with a UV/VIS DAD detector. The amount of enterobacteria in fresh cheese exceeded 105 CFU.g‑1. In smear-ripened cheese flavourless (Romadur type, the amount was >103 CFU.g-1 and 104-105 CFU.g-1 in smear-ripened cheese with flavour. Biogenic amines were observed in two groups of blue cheeses (white veined cheese and blue veined cheese and smear-ripened cheeses. In both groups, there is a possibility of the presence of biogenic amines because the number of microorganisms and concentration of free amino acids increase during ripening. In ten samples of soft smear-ripening acid cheese and in smear-ripened cheese, the total content of biogenic amines were 22-1000 mg.kg-1 and in 5 samples of these cheeses, it was in range 1000-6000 mg.kg-1. The total amount of biogenic amines in the blue cheeses were in range 40-600 mg.kg-1. The presense of the tyramine was observed in the all analysed cheeses. The tyramine producing strains generated more than 900 mg.kg-1 of this biogenic amine. The production of tryptamine in the analysed cheeses was not proved by this study. The results of this study show that biogenic amines and polyamines are common in cheese. However, in some cases, they can pose a significant health danger for consumers. Any legislative control authority does not monitor them, as they are secondary metabolites even

  19. The effect of fluorine substitution in alcohol-amine complexes

    DEFF Research Database (Denmark)

    Hansen, Anne Schou; Du, Lin; Kjærgaard, Henrik Grum

    2014-01-01

    The effect of fluorine substitution on the hydrogen bond strength in alcohol-amine molecular complexes was investigated, with a combination of vapour phase infrared spectroscopy and theoretical calculations. The complexes were combined from methanol (MeOH), ethanol (EtOH) and trifluoroethanol (TFE...... elucidated by Natural Bond Orbital, Atoms in Molecules and Non-covalent Interactions analysis. We find that the alcohol-amine complexes with TFE as the hydrogen bond donor form stronger hydrogen bonds and that secondary interactions between the monomers increase from MeOH to EtOH to TFE. TFE is a stronger...

  20. Reaction mechanisms of secondary and tertiary amines with OH and NO3 radicals

    Science.gov (United States)

    Emissions of aliphatic amines are common near agricultural facilities such as animal feed lots. Determining the reactions of these amines with common atmospheric radicals is important to understanding both daytime and nighttime atmospheric chemistry. Several smog chamber experiments were conducted ...

  1. Monomers for thermosetting and toughening epoxy resins. [glycidyl amine derivatives, propargyl-containing amines, and mutagenic testing of aromatic diamines

    Science.gov (United States)

    Pratt, J. R.

    1981-01-01

    Eight glycidyl amines were prepared by alkylating the parent amine with epichlorohydrin to form chlorohydrin, followed by cyclization with aqueous NaOH. Three of these compounds contained propargyl groups with postcuring studies. A procedure for quantitatively estimating the epoxy content of these glycidyl amines was employed for purity determination. Two diamond carbonates and several model propargly compounds were prepared. The synthesis of three new diamines, two which contain propargyloxy groups, and another with a sec-butyl group is in progress. These materials are at the dinitro stage ready for the final hydrogenation step. Four aromatic diamines were synthesized for mutagenic testing purposes. One of these compounds rapidly decomposes on exposure to air.

  2. Catalytic Enantioselective Allylic Amination of Olefins for the Synthesis of ent-Sitagliptin.

    Science.gov (United States)

    Bao, Hongli; Bayeh, Liela; Tambar, Uttam K

    2013-11-01

    The presence of nitrogen atoms in most chiral pharmaceutical drugs has motivated the development of numerous strategies for the synthesis of enantioenriched amines. Current methods are based on the multi-step transformation of pre-functionalized allylic electrophiles into chiral allylic amines. The enantioselective allylic amination of unactivated olefins represents a more direct and attractive strategy. We report the enantioselective synthesis of ent-sitagliptin via an allylic amination of an unactivated terminal olefin.

  3. Super absorbent conjugated microporous polymers: a synergistic structural effect on the exceptional uptake of amines.

    Science.gov (United States)

    Liu, Xiaoming; Xu, Yanhong; Guo, Zhaoqi; Nagai, Atsushi; Jiang, Donglin

    2013-04-21

    Conjugated microporous polymers exhibit a synergistic structural effect on the exceptional uptake of amines, whereas the dense porphyrin units facilitate uptake, the high porosity offers a large interface and the swellability boosts capacity. They are efficient in the uptake of both vapor and liquid amines, are applicable to various types of amines, and are excellent for cycle use.

  4. Conversion of alcohols to enantiopure amines through dual-enzyme hydrogen-borrowing cascades

    NARCIS (Netherlands)

    Mutti, F.G.; Knaus, T.; Scrutton, N.S.; Breuer, M.; Turner, N.J.

    2015-01-01

    α-Chiral amines are key intermediates for the synthesis of a plethora of chemical compounds at industrial scale. We present a biocatalytic hydrogen-borrowing amination of primary and secondary alcohols that allows for the efficient and environmentally benign production of enantiopure amines. The met

  5. Whole-​cell biocatalysts for stereoselective C-H amination reactions

    NARCIS (Netherlands)

    Both, P.; Busch, H.; Kelly, P.P.; Mutti, F.G.; Turner, N.J.; Flitsch, S.L.

    2016-01-01

    Enantiomerically pure chiral amines are ubiquitous chemical building blocks in bioactive pharmaceutical products and their synthesis from simple starting materials is of great interest. One of the most attractive strategies is the stereoselective installation of a chiral amine through C H amination,

  6. Cooperative catalysis by palladium and a chiral phosphoric acid: enantioselective amination of racemic allylic alcohols.

    Science.gov (United States)

    Banerjee, Debasis; Junge, Kathrin; Beller, Matthias

    2014-11-24

    Cooperative catalysis by [Pd(dba)2] and the chiral phosphoric acid BA1 in combination with the phosphoramidite ligand L8 enabled the efficient enantioselective amination of racemic allylic alcohols with a variety of functionalized amines. This catalytic protocol is highly regio- and stereoselective (up to e.r. 96:4) and furnishes valuable chiral amines in almost quantitative yield.

  7. Copper(II)-catalyzed electrophilic amination of quinoline N-oxides with O-benzoyl hydroxylamines.

    Science.gov (United States)

    Li, Gang; Jia, Chunqi; Sun, Kai; Lv, Yunhe; Zhao, Feng; Zhou, Kexiao; Wu, Hankui

    2015-03-21

    Copper acetate-catalyzed C-H bond functionalization amination of quinoline N-oxides was achieved using O-benzoyl hydroxylamine as an electrophilic amination reagent, thereby affording the desired products in moderate to excellent yields. Electrophilic amination can also be performed in good yield on a gram scale.

  8. Aerosol and cloud chemistry of amines from CCS - reactivity experiments and numerical modeling

    Science.gov (United States)

    Weller, Christian; Tilgner, Andreas; Herrmann, Hartmut

    2013-04-01

    Capturing CO2 from the exhaust of power plants using amine scrubbing is a common technology. Therefore, amines can be released during the carbon capture process. To investigate the tropospheric chemical fate of amines from CO2 capturing processes and their oxidation products, the impact of aqueous aerosol particles and cloud droplets on the amine chemistry has been considered. Aqueous phase reactivity experiments of NO3 radicals and ozone with relevant amines and their corresponding nitrosamines were performed. Furthermore, nitrosamine formation and nitrosamine photolysis was investigated during laboratory experiments. These experiments implicated that aqueous phase photolysis can be an effective sink for nitrosamines and that ozone is unreactive towards amines and nitrosamines. Multiphase phase oxidation schemes of amines, nitrosamines and amides were developed, coupled to the existing multiphase chemistry mechanism CAPRAM and built into the Lagrangian parcel model SPACCIM using published and newly measured data. As a result, both deliquescent particles and cloud droplets are important compartments for the multiphase processing of amines and their products. Amines can be readily oxidised by OH radicals in the gas and cloud phase during daytime summer conditions. However, amine oxidation is restricted during winter conditions with low photochemical activity leading to long lifetimes of amines. The importance of the gas and aqueous phase depends strongly on the partitioning of the different amines. Furthermore, the simulations revealed that the aqueous formation of nitrosamines in aerosol particles and could droplets is not a relevant process under tropospheric conditions.

  9. Synthesis and Properties of An Aminated hypocrellin B

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A new aminated-perylenequinone derivative 2 was synthesized by the reaction of 1 ( hypocrellin B ) with 6-aminohexanoic-acid. The structure of 2 was identified by UV-Vis, MS, IR and 1H-NMR. The amphiphility, spectrum and photochemical properties of 2 were reported.

  10. Iron catalysed direct alkylation of amines with alcohols

    NARCIS (Netherlands)

    Yan, Tao; Feringa, Ben L; Barta, Katalin

    2014-01-01

    The selective conversion of carbon-oxygen bonds into carbon-nitrogen bonds to form amines is one of the most important chemical transformations for the production of bulk and fine chemicals and pharma intermediates. An attractive atom-economic way of carrying out such C-N bond formations is the dire

  11. Use of mixed amines for CO[sub 2] removal

    Energy Technology Data Exchange (ETDEWEB)

    Shahi, P.

    1993-08-01

    The process of sweetening of gas mixtures has widespread applications. The amine process involves absorbing the acid gas in an absorption column and subsequently regenerating the solvent in a stripping column by the application of heat. Monoethanolamine (MEA) is an excellent solvent in terms of its absorption characteristics while methyldiethanolamine (MDEA) can be regenerated using less energy. However, despite its higher capacity to absorb CO[sub 2], MDEA has slower mass transfer rates compared to MEA due to its slower reaction, so that blending the two amines to obtain their individual characteristics is attractive. Experimental studies were conducted on a pilot scale unit consisting of an absorber and a stripper. The effects of various process parameters were studied for single as well as mixed amines. It was observed that a mixture of MEA and MDEA has vastly improved absorption characteristics and at the same time consumes less energy during regeneration. A simple solubility model is presented which predicts the solubility of CO[sub 2] in individual amines and their mixtures. Excellent agreement is found with existing experimental data and predictions of another rigorous solubility model. 120 refs., 59 figs., 6 tabs.

  12. Inhibition of chickpea seedling copper amine oxidases by tetraethylenepentamine

    Directory of Open Access Journals (Sweden)

    Sona Talaei

    2012-01-01

    Full Text Available Copper amine oxidases are important enzymes, which contribute to the regulation of mono- and polyamine levels. Each monomer contains one Cu(II ion and 2,4,5-trihydroxyphenylalanine (TPQ as cofactors. They catalyze the oxidative deamination of primary amines to aldehydes with a ping-pong mechanism consisting of a transamination. The mechanism is followed by the transfer of two electrons to molecular oxygen which is reduced to hydrogen peroxide. Inhibitors are important tools in the study of catalytic properties of copper amine oxidases and they also have a wide application in physiological research. In this study, purification of the chickpea seedling amine oxidase, was done via salting out by ammonium sulfate and dialysis, followed by DEAE-cellulose column chromatography. By using the Lineweaver - Burk plot, the Km and Vm of the enzyme were found to be 3.3 mM and 0.95 mmol/min/mg, respectively. In this study, the interaction of chickpea diamino oxidase with tetraethylene- pentamine was studied. Analysis of kinetic data indicated that tetraethylenepentamine (with Ki=0.1 mM inhibits the enzyme by linear mixed inhibitory effect.

  13. Heterogeneous uptake of amines by citric acid and humic acid.

    Science.gov (United States)

    Liu, Yongchun; Ma, Qingxin; He, Hong

    2012-10-16

    Heterogeneous uptake of methylamine (MA), dimethylamine (DMA), and trimethylamine (TMA) onto citric acid and humic acid was investigated using a Knudsen cell reactor coupled to a quadrupole mass spectrometer at 298 K. Acid-base reactions between amines and carboxylic acids were confirmed. The observed uptake coefficients of MA, DMA, and TMA on citric acid at 298 K were measured to be 7.31 ± 1.13 × 10(-3), 6.65 ± 0.49 × 10(-3), and 5.82 ± 0.68 × 10(-3), respectively, and showed independence of sample mass. The observed uptake coefficients of MA, DMA, and TMA on humic acid at 298 K increased linearly with sample mass, and the true uptake coefficients of MA, DMA, and TMA were measured to be 1.26 ± 0.07 × 10(-5), 7.33 ± 0.40 × 10(-6), and 4.75 ± 0.15 × 10(-6), respectively. Citric acid, having stronger acidity, showed a higher reactivity than humic acid for a given amine; while the steric effect of amines was found to govern the reactivity between amines and citric acid or humic acid.

  14. Dissolving Carboxylic Acids and Primary Amines on the Overhead Projector

    Science.gov (United States)

    Solomon, Sally D.; Rutkowsky, Susan A.

    2010-01-01

    Liquid carboxylic acids (or primary amines) with limited solubility in water are dissolved by addition of aqueous sodium hydroxide (or hydrochloric acid) on the stage of an overhead projector using simple glassware and very small quantities of chemicals. This effective and colorful demonstration can be used to accompany discussions of the…

  15. Amine-phenyl multi-component gradient stationary phases.

    Science.gov (United States)

    Dewoolkar, Veeren C; Kannan, Balamurali; Ashraf, Kayesh M; Higgins, Daniel A; Collinson, Maryanne M

    2015-09-04

    Continuous multi-component gradients in amine and phenyl groups were fabricated using controlled rate infusion (CRI). Solutions prepared from either 3-aminopropyltriethoxysilane (APTEOS) or phenyltrimethoxysilane (PTMOS) were infused, in a sequential fashion, at a controlled rate into an empty graduated cylinder housing a vertically aligned thin layer chromatography (TLC) plate. The hydrolyzed precursors reacted with an abundance of silanol (SiOH) groups on the TLC plates, covalently attaching the functionalized silane to its surface. The extent of modification by phenyl and amine was determined by the kinetics of each reaction and the exposure time at each point along the TLC plate. The local concentrations of phenyl and amine were measured using diffuse reflectance spectroscopy and X-ray photoelectron spectroscopy, respectively. The profile of the multi-component gradients strongly depended on the order of infusion, the direction of the gradient and the presence of available surface silanol groups. A slightly higher amount of phenyl can be deposited on the TLC plate by first modifying its surface with amine groups as they serve as a catalyst, enhancing condensation. Separation of water- and fat-soluble vitamins and the control of retention factors were demonstrated on the multi-component gradient TLC plates. Uniformly modified and single-component TLC plates gave different separations compared to the multi-component gradient plates. The retention factors of the individual vitamins depended on the order of surface modification, the spotting end, and whether the multi-component gradients align or oppose each other.

  16. Polymeric Amines by chemical modifications of alternating aliphatic polyketones

    NARCIS (Netherlands)

    Zhang, Youchun; Broekhuis, A. A.; Stuart, Marc C. A.; Picchioni, F.

    2008-01-01

    Alternating, aliphatic polyketones were chemically modified by using di-amines to obtain polymeric products having pendant amino groups. The used reaction, Paal-Knorr, involves the formation of pyrrole rings along the polyketone backbone. The corresponding kinetics and final conversions are clearly

  17. Peptide N-Amination Supports β-Sheet Conformations.

    Science.gov (United States)

    Sarnowski, Matthew P; Kang, Chang Won; Elbatrawi, Yassin M; Wojtas, Lukasz; Del Valle, Juan R

    2017-02-13

    The conformational heterogeneity of backbone N-substituted peptides limits their ability to adopt stable secondary structures. Herein, we describe a practical synthesis of backbone aminated peptides that readily adopt β-sheet folds. Data derived from model N-amino peptides suggest that extended conformations are stabilized through cooperative steric, electrostatic, and hydrogen-bonding interactions.

  18. Experimental and theoretical investigations into the stability of cyclic aminals

    Directory of Open Access Journals (Sweden)

    Edgar Sawatzky

    2016-10-01

    Full Text Available Background: Cyclic aminals are core features of natural products, drug molecules and important synthetic intermediates. Despite their relevance, systematic investigations into their stability towards hydrolysis depending on the pH value are lacking.Results: A set of cyclic aminals was synthesized and their stability quantified by kinetic measurements. Steric and electronic effects were investigated by choosing appropriate groups. Both molecular mechanics (MM and density functional theory (DFT based studies were applied to support and explain the results obtained. Rapid decomposition is observed in acidic aqueous media for all cyclic aminals which occurs as a reversible reaction. Electronic effects do not seem relevant with regard to stability, but the magnitude of the conformational energy of the ring system and pKa values of the N-3 nitrogen atom.Conclusion: Cyclic aminals are stable compounds when not exposed to acidic media and their stability is mainly dependent on the conformational energy of the ring system. Therefore, for the preparation and work-up of these valuable synthetic intermediates and natural products, appropriate conditions have to be chosen and for application as drug molecules their sensitivity towards hydrolysis has to be taken into account.

  19. Biogenic amines in rhizobia and legume root nodules.

    Science.gov (United States)

    Fujihara, Shinsuke

    2009-01-01

    Root-nodule bacteria (rhizobia) are of great importance for nitrogen acquisition through symbiotic nitrogen fixation in a wide variety of leguminous plants. These bacteria differ from most other soil microorganisms by taking dual forms, i.e. a free-living form in soils and a symbiotic form inside of host legumes. Therefore, they should have a versatile strategy for survival, whether inhabiting soils or root nodules formed through rhizobia-legume interactions. Rhizobia generally contain large amounts of the biogenic amine homospermidine, an analog of spermidine which is an essential cellular component in most living systems. The external pH, salinity and a rapid change in osmolarity are thought to be significant environmental factors affecting the persistence of rhizobia. The present review describes the regulation of homospermidine biosynthesis in response to environmental stress and its possible functional role in rhizobia. Legume root nodules, an alternative habitat of rhizobia, usually contain a variety of biogenic amines besides homospermidine and the occurrence of some of these amines is closely associated with rhizobial infections. In the second half of this review, novel biogenic amines found in certain legume root nodules and the mechanism of their synthesis involving cooperation between the rhizobia and host legume cells are also described.

  20. Effects of amine fluoride on biofilm growth and salivary pellicles

    NARCIS (Netherlands)

    Van der Mei, HC; Engels, E; de Vries, Jacob; Busscher, HJ

    2008-01-01

    The amine fluoride (AmF) N'-octadecyltrimethylendiamine-N, N,N'-tris(2-ethanol)-dihydrofluoride is a cationic antimicrobial which can have beneficial effects on plaque formation. Here, we determine changes in pellicle and bacterial cell surface properties of the strains Actinomyces naeslundii HM1, S

  1. The Reactions of 3, 7-Dinitrodibenzobromolium Salt with Some Amines

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The reactions of 3,7-dinitrodibenzobromolium salt with some amines were studied. A reaction mechanism based on the structure of the major product 6 and the minor product 7 was proposed. The reaction was considered to proceed via a substituted benzyene intermediate.

  2. Selective acylation of primary amines in peptides and proteins

    NARCIS (Netherlands)

    Abello, N.; Kerstjens, H.A.M.; Postma, D.S; Bischoff, Rainer

    2007-01-01

    N-hydroxysuccinimide (NHS) esters are derivatizing agents that target primary amine groups. However, even a small molar excess of NHS may lead to acylation of hydroxyl-containing amino acids as a side reaction. We report a straightforward method for the selective removal of ester-linked acyl groups

  3. Economic Considerations for Selecting an Amine Donor in Biocatalytic Transamination

    DEFF Research Database (Denmark)

    Tufvesson, Pär; Nordblad, Mathias; Krühne, Ulrich

    2015-01-01

    The industrial implementation of biocatalysis for production of pharma and fine chemicals has grown substantially over recent years. An upcoming application is that of chiral synthesis of optically pure amines, a technology known for many years but that is now seeing a renewed and wider interest ...

  4. Synthesis of Oxazolidinone and Tosyl Enamines by Tertiary Amine Catalysis.

    Science.gov (United States)

    Eddy, Nicholas A; Morse, Peter D; Morton, Martha D; Fenteany, Gabriel

    2011-01-01

    A procedure for the synthesis of oxazolidinone and tosyl enamines is reported. Alkynoyl oxazolidinones and tosyl imides undergo reaction to form enamines in the presence of catalytic amounts of tertiary amines. The data suggest that an amide anion is formed during the reaction, which undergoes conjugate addition to form the final product.

  5. Cytocompatibility of amine functionalized carbon nanoparticles grafted on polyethylene

    Energy Technology Data Exchange (ETDEWEB)

    Žáková, Pavlína, E-mail: pavlina.zakova@vscht.cz [Department of Solid State Engineering, University of Chemistry and Technology, 166 28 Prague 6 (Czech Republic); Slepičková Kasálková, Nikola [Department of Solid State Engineering, University of Chemistry and Technology, 166 28 Prague 6 (Czech Republic); Kolská, Zdeňka [Faculty of Science, J. E. Purkyně University, Ústí nad Labem (Czech Republic); Leitner, Jindřich [Department of Solid State Engineering, University of Chemistry and Technology, 166 28 Prague 6 (Czech Republic); Karpíšková, Jana; Stibor, Ivan [Institute for Nanomaterials, Advanced Technologies and Innovation, Technical University of Liberec (Czech Republic); Slepička, Petr; Švorčík, Václav [Department of Solid State Engineering, University of Chemistry and Technology, 166 28 Prague 6 (Czech Republic)

    2016-03-01

    Five types of amide–amine Carbon Nano-Particles (CNPs) were prepared by functionalization of CNPs and characterized by several analytical methods. The successful grafting of amines on CNPs was verified by X-ray photoelectron spectroscopy (XPS), organic elemental analysis and electrokinetic analysis. The size and morphology of CNPs were determined from transmission electron microscopy. The surface area and porosity of CNPs were examined by adsorption and desorption isotherms. Differential scanning calorimetry was used to investigate thermal stability of CNPs. The amount of bonded amine depends on its dimensionality arrangement. Surface area and pore volumes of CNPs decrease several times after individual amino-compound grafting. Selected types of functionalized CNPs were grafted onto a plasma activated surface of HDPE. The successful grafting of CNPs on the polymer surface was verified by XPS. Wettability was determined by contact angle measurements. Surface morphology and roughness were studied by atomic force microscopy. A dramatic decrease of contact angle and surface morphology was observed on CNP grafted polymer surface. Cytocompatibility of modified surfaces was studied in vitro, by determination of adhesion, proliferation and viability of vascular smooth muscle cells (VSMCs). Grafting of CNPs onto the polymer surface has a positive effect on the adhesion, proliferation and viability of VSMCs. - Highlights: • Amine functionalized CNPs were successfully grafted on HDPE surface. • Significant change to the positive zeta potential for grafted CNPs was induced. • Grafting of CNPs significantly enhanced cell cytocompatibility and viability. • Homogeneous distribution of cells with correct size was achieved.

  6. Trimodal nanoporous silica as a support for amine-based CO2 adsorbents: Improvement in adsorption capacity and kinetics

    Science.gov (United States)

    Chen, Chao; Bhattacharjee, Samiran

    2017-02-01

    A trimodal nanoporous silica (TS) having unique trimodal pore structure viz., internal mesopores, textural mesopores and interconnected macropores, has been functionalized with amine using two different methods covalent grafting and wet impregnation. Both were studied as nanocomposite sorbents for CO2 capture. The effects of the amine loading, immobilization processes and the type of support were investigated. Commercially available silica gel (SG) with a purely mesoporous structure was studied as the support for the amine in order to compare differences in pore structure and amine loading with differences in CO2 adsorption capacity and kinetics. Amine-grafted TS exhibited much faster CO2 adsorption kinetics at 35 °C than amine-grafted SG. At the same amine loading, amine-impregnated TS showed higher CO2 adsorption capacity and faster CO2 adsorption kinetics than amine-impregnated SG. The CO2 adsorption capacity of amine-impregnated TS increased as the amine loading increased until 70%, with the highest value of 172 mg/g, while the amine-impregnated SG reached the highest CO2 adsorption capacity of only 78 mg/g at 40% amine loading. More importantly, amine-impregnated as-prepared TS exhibited even higher CO2 capture capacity than amine-impregnated TS when the amine loading was below 60%. Results suggest that amine-modified trimodal nanoporous silica sorbents meet the challenges of current CO2 capture technology.

  7. Atmospheric Amines and Ammonia Measured with a Chemical Ionization Mass Spectrometer (CIMS)

    Energy Technology Data Exchange (ETDEWEB)

    You, Y.; Kanawade, V. P.; de Gouw, J. A.; Guenther, Alex B.; Madronich, Sasha; Sierra-Hernandez, M. R.; Lawler, M.; Smith, James N.; Takahama, S.; Ruggeri, G.; Koss, A.; Olson, K.; Baumann, K.; Weber, R. J.; Nenes, A.; Guo, H.; Edgerton, Eric S.; Porcelli, L.; Brune, W. H.; Goldstein, Allen H.; Lee, S.-H

    2014-11-19

    We report ambient measurements of amines and ammonia with a fast response chemical ionization mass spectrometer (CIMS) in a Southeastern U.S. forest in Alabama and a moderately polluted Midwestern site during the summer. In the Alabama forest, mostly C3-amines (from pptv to tens of pptv) and ammonia (up to 2 ppbv) were detected on a daily basis. C3-amines and ammonia showed similar diurnal trends and temperature and wind direction dependences, and were not associated with transported CO and SO2 plumes. Consistent with temperature dependences, amine and ammonia in the gas and aerosol phases showed opposite diurnal trends, indicating gas-to-particle partitioning of amines and ammonia. Temperature dependences also imply reversible processes of amines and ammonia evaporation from soil surfaces in daytime and deposition of amines and ammonia to soil surfaces at nighttime. Various amines (C1-C6) at the pptv level were observed in the transported biomass burning plumes, showing that biomass burning can be a substantial source of amines in the Southeast U.S. At the moderately polluted Kent site, higher concentrations of amines (C1-C6, from pptv to tens of pptv) and ammonia (up to 6 ppbv) were detected. Diurnal variations of C1- to C3-amines and ammonia were correlated with the ambient temperature. C4- to C6-amines showed abrupt increases during the nighttime, suggesting that they were emitted from local sources. These abundant amines and ammonia may in part explain the frequent new particle formation events reported from Kent. Lower amine concentrations at the rural forested site highlight the importance of constraining anthropogenic sources of amines.

  8. Atmospheric amines and ammonia measured with a Chemical Ionization Mass Spectrometer (CIMS

    Directory of Open Access Journals (Sweden)

    Y. You

    2014-06-01

    Full Text Available We report ambient measurements of amines and ammonia with a~fast response chemical ionization mass spectrometer (CIMS in a southeastern US forest in Alabama and a~moderately polluted Midwestern site during the summer. In the Alabama forest, mostly C3-amines (from pptv to tens of pptv and ammonia (up to 2 ppbv were detected on a daily basis. C3-amines and ammonia showed similar diurnal trends and temperature and wind direction dependences, and were not associated with transported CO and SO2 plumes. Consistent with temperature dependences, amine and ammonia in the gas and aerosol phases showed opposite diurnal trends, indicating gas-to-particle partitioning of amines and ammonia. Temperature dependences also imply reversible processes of amines and ammonia evaporation from soil surfaces in daytime and deposition of amines and ammonia to soil surfaces at nighttime. Various amines (C1–C6 at the pptv level were observed in the transported biomass burning plumes, showing that biomass burning can be a substantial source of amines in the Southeast US. At the moderately polluted Kent site, higher concentrations of amines (C1–C6, from pptv to tens of pptv and ammonia (up to 6 ppbv were detected. Diurnal variations of C1- to C3-amines and ammonia were correlated with the ambient temperature. C4- to C6-amines showed abrupt increases during the nighttime, suggesting that they were emitted from local sources. These abundant amines and ammonia may in part explain the frequent new particle formation events reported from Kent. Lower amine concentrations at the rural forested site highlight the importance of constraining anthropogenic sources of amines.

  9. INFLUENCE OF MOLECULAR STRUCTURES OF SECONDARY AMINE TERMINATED POLY(ESTER-AMINE)S ON THE CURING PERFORMANCE WITH EPOXY RESIN

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Five secondary amine terminated poly(ester-amine)s (defined as PEA) with controlled molecular structures were synthesized through reacting excessive piperazine with phthalicdiglycol diacrylate (PDDA) and 1,1,1-trimethylolpropane triacrylate (TMPTA) at a constant secondary amine/acrylate group ratio of 1.5/1 and at different PDDA/TMPTA molar ratios.Both IR and 1H-NMR spectra indicated that all acrylate groups were consumed in the reaction, based on which the structural parameters were calculated from the 1H-NMR spectra. With decreasing PDDA/TMPTA ratio, the content of secondary amine, degree of branching, molecular weight, Tg and Td increased accordingly. These polymers were further used as both crosslinkers and flexibilizers for a linear epoxy resin E51 to form cured films under ambient condition, The gel content,relative hardness and Tg of the resulting films increased as PEA molecules changed from linear to highly branching structures. Due to the flexibility of PEA molecules, all the films possessed excellent mechanical performance.

  10. Poly(amido amine)s as Gene Delivery Vectors: Effects of Quaternary Nicotinamide Moieties in the Side Chains

    NARCIS (Netherlands)

    Mateos Timoneda, Miguel A.; Lok, Martin C.; Hennink, Wim E.; Feijen, Jan; Engbersen, Johan F.J.

    2008-01-01

    To evaluate the effect of quaternary nicotinamide pendant groups on gene delivery properties, a series of poly(amido amine) (co)polymers were synthesized by Michael addition polymerization of N, N-cystaminebisacrylamide with variable ratios of 1-(4-aminobutyl)-3-carbamoylpyridinium (Nic-BuNH2), and

  11. Bifunctional Catalysis: Direct Reductive Amination of Aliphatic Ketones with an Iridium-Phosphate Catalyst

    Directory of Open Access Journals (Sweden)

    Barbara Villa-Marcos

    2010-04-01

    Full Text Available Chiral amines are one of the ubiquitous functional groups in fine chemical, pharmaceutical and agrochemical products, and the most convenient, economical, and eco-benign synthetic pathway to these amines is direct asymmetric reductive amination (DARA of prochiral ketones. This paper shows that a wide range of aliphatic ketones can be directly aminated under hydrogenation conditions, affording chiral amines with good to excellent yields and with enantioselectivities up to 96% ee. The catalysis is effected by the cooperative action of a cationic Cp*Ir(III complex and its phosphate counteranion.

  12. Mechanism of the N-Hydroxylation of Primary and Secondary Amines by Cytochrome P450

    DEFF Research Database (Denmark)

    Seger, Signe T.; Rydberg, Patrik; Olsen, Lars

    2015-01-01

    ) for four different amines (aniline, N-methylaniline, propan-2-amine, and dimethylamine). The hydrogen abstraction and rebound mechanism is found to be preferred over a direct oxygen transfer mechanism for all four amines. However, in contrast to the same mechanism for the hydroxylation of aliphatic carbon......Cytochrome P450 enzymes (CYPs) metabolize alkyl- and arylamines, generating several different products. For the primary and secondary amines, some of these reactions result in hydroxylated amines, which may be toxic. Thus, when designing new drugs containing amine groups, it is important to be able...... to predict if a given compound will be a substrate for CYPs, in order to avoid toxic metabolites, and hence to understand the mechanism that is utilized by CYPs. Two possible mechanisms, for the N-hydroxylation of primary and secondary amines mediated by CYPs, are studied by density functional theory (DFT...

  13. Electron spin resonance study of chloroplast photosynthetic activity in the presence of amphiphilic amines.

    Science.gov (United States)

    Sersen, F; Balgavý, P; Devínsky, F

    1990-12-01

    Electron spin resonance spectroscopy (ESR) was used to study the effects of amphiphilic amines of the carbamate, amide, and ester type and amine oxide on the photosynthetic system of spinach chloroplasts. The ESR signal II connected to the photosynthetic center PS II donor side was observed to diminish in the presence of amines, whereas that of PS I remained unchanged. The inhibition of PS II increased with the increasing of amine concentration. In the presence of amines, the light: dark chloroplast ESR signals ratio as well as the intensity of the ESR signal of unbound Mn2+ increased. It is suggested that the amphiphilic amines affect the structure of PS II and the electron transfer to PS I. The effects of the amines tested on the photosynthetic system correlate with their potency to perturb the lipid membrane structure.

  14. Adsorption of catechol from aqueous solution by aminated hypercrosslinked polymers

    Institute of Scientific and Technical Information of China (English)

    SUN Yue; LI Xiao-tao; XU Chao; CHEN Jin-long; LI Ai-min; ZHANG Quan-xing

    2005-01-01

    Adsorption of catechol from aqueous solution with the hypercrosslinked polymeric adsorbent NDA-100 and its derivatives AH-1,AH-2 and AH-3 aminated by dimethylamine, the commercial resin Amberlite XAD-4 and weakly basic anion exchanger resin D301 was compared. It was found that the aminated hypercrosslinked resins had the highest adsorption capacities among the tested polymers. The empirical Freundlich equation was successfully employed to describe the adsorption process. Specific surface area and micropore structure of the adsorbent, in company with tertiary amino groups on matrix affected the adsorption performance towards catechol. In addition,thermodynamic study was carried out to interpret the adsorption mechanism. Kinetic study testified that the tertiary amino groups on the polymer matrix could decrease the adsorption rate and increase the adsorption apparent activation energy.

  15. The effect of fluorine substitution in alcohol-amine complexes

    DEFF Research Database (Denmark)

    Hansen, Anne Schou; Du, Lin; Kjærgaard, Henrik Grum

    2014-01-01

    The effect of fluorine substitution on the hydrogen bond strength in alcohol-amine molecular complexes was investigated, with a combination of vapour phase infrared spectroscopy and theoretical calculations. The complexes were combined from methanol (MeOH), ethanol (EtOH) and trifluoroethanol (TFE...... formation were determined by combining a calculated intensity and the measured integrated absorbance. The observation of two transitions in the alcohol-DMA complexes provides an opportunity for two independent determinations of the equilibrium constants. Molecular interactions between the monomers were...... elucidated by Natural Bond Orbital, Atoms in Molecules and Non-covalent Interactions analysis. We find that the alcohol-amine complexes with TFE as the hydrogen bond donor form stronger hydrogen bonds and that secondary interactions between the monomers increase from MeOH to EtOH to TFE. TFE is a stronger...

  16. The weak fundamental NH-stretching transition in amines

    Science.gov (United States)

    Schrøder, Sidsel D.; Hansen, Anne S.; Wallberg, Jens H.; Nielsen, Anne R.; Du, Lin; Kjaergaard, Henrik G.

    2017-02-01

    Absolute intensities of NH-stretching fundamental and overtone transitions of gas phase aniline, methylamine, ethylamine, cyclopropylamine, methylethylamine, diethylamine and pyrrolidine have been measured with long path length conventional absorption spectroscopy. To support the assignments of NH-stretching transitions, transition frequencies and intensities were calculated with the local mode model using ab initio calculated local mode parameters and dipole moment functions obtained at the CCSD(T)-F12a/VDZ-F12 level of theory. For aniline, the absolute intensities of the NH-stretching transitions show the typical decrease of approximately an order of magnitude for each successive vibrational excitation. For methylamine, ethylamine, cyclopropylamine, methylethylamine, diethylamine and pyrrolidine, the observed absolute intensities of the fundamental NH-stretching transition is weak and of similar strength or even weaker than the corresponding first overtone transition. Characteristic for the amines with a normal fundamental intensity is a conjugated double bond next to the amine group.

  17. Debromination of endo-(+)-3-bromocamphor with primary amines

    Energy Technology Data Exchange (ETDEWEB)

    Markovic, Svetlana; Markovic, Violeta; Joksovic, Milan D.; Joksovic, Ljubinka, E-mail: ljubinka@kg.ac.rs [Department of Chemistry, Faculty of Science, University of Kragujevac (Serbia); Todorovic, Nina [Institute for Chemistry, Technology and Metallurgy, Belgrade (Serbia); Divjakovic, Vladimir [Department of Physics, University of Novi Sad (Serbia); Trifunovic, Snezana [Faculty of Chemistry, University of Belgrade, Belgrade, (Serbia)

    2013-07-15

    Reductive debromination of endo-(+)-3-bromocamphor with different primary amines followed by imine formation was investigated. This reaction requires simple experimental procedure without any organic solvent, metal or conventional reducing agent. A strong influence of amine polarity on the efficacy of debromination process was observed, and ethanolamine and ethylene diamine having sufficiently high boiling points can debrominate 3-bromocamphor giving corresponding camphanimines in good isolated yields. The mechanisms of debromination of 3-bromocamphor with ethanolamine and n-hexylamine were investigated at the B3LYP/6-311+G(d,p) level of theory. The radical mechanism was revealed, and it was shown that the reaction with more polar ethanolamine is energetically more favorable. (author)

  18. Nanoscale assembly of amine-functionalized colloidal iron oxide

    Energy Technology Data Exchange (ETDEWEB)

    Barick, K.C. [Department of Metallurgical Engineering and Materials Science, Indian Institute of Technology Bombay, Mumbai 400076 (India); Aslam, M. [Department of Physics, Indian Institute of Technology Bombay, Mumbai 400076 (India); Centre for Research in Nanotechnology and Science, Indian Institute of Technology Bombay, Mumbai 400076 (India); Prasad, Pottumarthi V. [Department of Radiology, Evanston Northwestern Healthcare, Evanston, IL 60201 (United States); Dravid, Vinayak P. [Department of Materials Science and Engineering, Northwestern University, Evanston, IL 60208 (United States); International Institute for Nanotechnology, Northwestern University, Evanston, IL 60208 (United States)], E-mail: v-dravid@northwestern.edu; Bahadur, Dhirendra [Department of Metallurgical Engineering and Materials Science, Indian Institute of Technology Bombay, Mumbai 400076 (India); Centre for Research in Nanotechnology and Science, Indian Institute of Technology Bombay, Mumbai 400076 (India)], E-mail: dhirenb@iitb.ac.in

    2009-05-15

    We demonstrate a single-step facile approach for highly water-stable assembly of amine-functionalized Fe{sub 3}O{sub 4} nanoparticles using thermal decomposition of Fe-chloride precursors in ethylene glycol medium in the presence of ethylenediamine. The average size of nanoassemblies is 40{+-}1 nm, wherein the individual nanoparticles are about 6 nm. Amine-functionalized properties are evident from Fourier transform infrared spectrometer (FTIR), thermal and elemental analyses. The saturation magnetization and spin-echo r{sub 2} of the nanoassemblies were measured to be 64.3 emu/g and 314.6 mM{sup -1} s{sup -1}, respectively. The higher value of relaxivity ratio (r{sub 2}/r{sub 1}=143) indicates that nanoassemblies are a promising high-efficiency T2 contrast agent platform.

  19. Nanoscale assembly of amine-functionalized colloidal iron oxide

    Science.gov (United States)

    Barick, K. C.; Aslam, M.; Prasad, Pottumarthi V.; Dravid, Vinayak P.; Bahadur, Dhirendra

    2009-05-01

    We demonstrate a single-step facile approach for highly water-stable assembly of amine-functionalized Fe 3O 4 nanoparticles using thermal decomposition of Fe-chloride precursors in ethylene glycol medium in the presence of ethylenediamine. The average size of nanoassemblies is 40±1 nm, wherein the individual nanoparticles are about 6 nm. Amine-functionalized properties are evident from Fourier transform infrared spectrometer (FTIR), thermal and elemental analyses. The saturation magnetization and spin-echo r2 of the nanoassemblies were measured to be 64.3 emu/g and 314.6 mM -1 s -1, respectively. The higher value of relaxivity ratio ( r2/ r1=143) indicates that nanoassemblies are a promising high-efficiency T2 contrast agent platform.

  20. Aromatic Esters of Bicyclic Amines as Antimicrobials against Streptococcus pneumoniae.

    Science.gov (United States)

    de Gracia Retamosa, María; Díez-Martínez, Roberto; Maestro, Beatriz; García-Fernández, Esther; de Waal, Bas; Meijer, E W; García, Pedro; Sanz, Jesús M

    2015-11-09

    A double approach was followed in the search of novel inhibitors of the surface choline-binding proteins (CBPs) of Streptococcus pneumoniae (pneumococcus) with antimicrobial properties. First, a library of 49 rationally-designed esters of alkyl amines was screened for their specific binding to CBPs. The best binders, being esters of bicyclic amines (EBAs), were then tested for their in vitro effect on pneumococcal growth and morphology. Second, the efficiency of EBA-induced CBP inhibition was enhanced about 45,000-fold by multivalency effects upon synthesizing a poly(propylene imine) dendrimer containing eight copies of an atropine derivative. Both approaches led to compounds that arrest bacterial growth, dramatically decrease cell viability, and exhibit a protection effect in animal disease models, demonstrating that the pneumococcal CBPs are adequate targets for the discovery of novel antimicrobials that overcome the currently increasing antimicrobial resistance issues.

  1. Structural Influence on Excited State Dynamics in Simple Amines

    DEFF Research Database (Denmark)

    Klein, Liv Bærenholdt

    is femtosecond time-resolved photoelectron velocity map imaging (VMI), which is a newtechnique in the Copenhagen lab. The design, building and implementation of the VMI spectrometer has been a very substantial part of the thesis work. This techniques oers enhanced information content in the form of ecient......Simple amines are basic model system of nitrogen-containing chromophores that appear widely in nature. They are also ideal systems for detailed investigation of nonadiabatic dynamical processes and ultrafast temporal evolution of electronic states of the Rydberg type. This investigation, combining...... experiments with calculations, provides new insight into the nature of the internal conversion processes that mediate the dynamical evolution between Rydberg states, and how structural variations in simple amine system have a large impact on the non-adiabatic processes. The experimental method of choice...

  2. Asymmetric trienamine catalysis: new opportunities in amine catalysis.

    Science.gov (United States)

    Kumar, Indresh; Ramaraju, Panduga; Mir, Nisar A

    2013-02-07

    Amine catalysis, through HOMO-activating enamine and LUMO-activating iminium-ion formation, is receiving increasing attention among other organocatalytic strategies, for the activation of unmodified carbonyl compounds. Particularly, the HOMO-raising activation concept has been applied to the greatest number of asymmetric transformations through enamine, dienamine, and SOMO-activation strategies. Recently, trienamine catalysis, an extension of amine catalysis, has emerged as a powerful tool for synthetic chemists with a novel activation strategy for polyenals/polyenones. In this review article, we discuss the initial developments of trienamine catalysis for highly asymmetric Diels-Alder reactions with different dienophiles and emerging opportunities for other types of cycloadditions and cascade reactions.

  3. Electrophysiological effects of trace amines on mesencephalic dopaminergic neurons

    Directory of Open Access Journals (Sweden)

    Ada eLedonne

    2011-07-01

    Full Text Available Trace amines (TAs are a class of endogenous compounds strictly related to classic monoamine neurotransmitters with regard to their structure, metabolism and tissue distribution. Although the presence of TAs in mammalian brain has been recognized for decades, until recently they were considered to be by-products of amino acid metabolism or as ‘false’ neurotransmitters. The discovery in 2001 of a new family of G protein-coupled receptors (GPCRs, namely trace amines receptors, has re-ignited interest in TAs. In particular, two members of the family, trace amine receptor 1 (TA1 and trace amine receptor 2 (TA2, were shown to be highly sensitive to these endogenous compounds. Experimental evidence suggests that TAs modulate the activity of catecholaminergic neurons and that TA dysregulation may contribute to neuropsychiatric disorders, including schizophrenia, attention deficit hyperactivity disorder, depression and Parkinson’s disease, all of which are characterised by altered monoaminergic networks. Here we review recent data concerning the electrophysiological effects of TAs on the activity of mesencephalic dopaminergic neurons. In the context of recent data obtained with TA1 receptor knockout mice, we also discuss the mechanisms by which the activation of these receptors modulates the activity of these neurons. Three important new aspects of TAs action have recently emerged: (a inhibition of firing due to increased release of dopamine; (b reduction of D2 and GABAB receptor-mediated inhibitory responses (excitatory effects due to dysinhibition; and (c a direct TA1 receptor-mediated activation of GIRK channels which produce cell membrane hyperpolarization. While the first two effects have been well documented in our laboratory, the direct activation of GIRK channels by TA1 receptors has been reported by others, but has not been seen in our laboratory (Geracitano et al., 2004. Further research is needed to address this point, and to further

  4. Permeability and fluoride release of lining materials containing amine fluorides.

    Science.gov (United States)

    Nordbö, H; Eriksen, H M

    1976-11-01

    The addition of amine fluorides to a copal recin (Copalite) and a chlorine caoutchouc varnish (Pergut S-40) has been studied. The permeability of Copalite films was only slightly increased whereas the excellent film-forming qualities of Pergut S-40 were destroyed by the addition of fluorides. A high fluoride release was found initially from test films of the materials but within 2-3 weeks a decrease to very low fluoride levels was observed.

  5. [N,N-Bis(diphenyl-phosphino)isopropyl-amine]dibromidonickel(II).

    Science.gov (United States)

    Hapke, Marko; Wöhl, Anina; Peitz, Stephan; Müller, Bernd H; Spannenberg, Anke; Rosenthal, Uwe

    2009-02-06

    The title compound, [NiBr(2)(C(27)H(27)NP(2))], was synthesized by the reaction of NiBr(2)(dme) (dme is 1,2-dimethoxy-ethane) with N,N-bis-(diphenyl-phosphino)isopropyl-amine in methanol/tetra-hydro-furan. The nickel(II) center is coordinated by two P atoms of the chelating PNP ligand, Ph(2)PN(iPr)PPh(2), and two bromide ions in a distorted square-planar geometry.

  6. [Metabolism of various biogenic amines in acute viral neuroinfections].

    Science.gov (United States)

    Martynenko, I N; Shchegoleva, R A; Ponomarenko, V P; Leshchinskaia, E V; Kodkind, G Kh

    1983-01-01

    The metabolism of biogenic amines was examined in 62 patients with various acute viral neuroinfections. The control group consisted of 57 persons. Depending on the process character and disease period variations of the levels of serotonin, 5-hydroxyindolylacetic acid, coeruloplasmin and histamine were discovered. A comparison of the results obtained with the clinical course of the diseases revealed a certain correlation, especially in patients with acute meningoencephalitis.

  7. Metabolic activation of aromatic amines and azo dyes.

    Science.gov (United States)

    Bartsch, H

    1981-01-01

    Aromatic amines, amides and nitro compounds are a class of chemicals that produce tumors in a wide variety of tissues in experimental animals, including liver, urinary bladder, forestomach, small intestine, Zymbal's gland, subcutaneous tissue or skin. In man, exposure to some aromatic amines is associated with tumours of the urinary bladder and carcinoma of the renal pelvis. Their biological activity as carcinogens or genotoxic agents is, in all the cases that have been studied in detail, dependent on metabolic activation in vivo, occurring by multiple pathways. Differences in these metabolic pathways may largely account for the differences in tissues and species susceptibilities to cancer induction. Carcinogenicity of aromatic amines or amides is dependent on their oxidation to N-hydroxy derivatives, whilst the carcinogenicity of aromatic nitro compounds is linked to their reduction to hydroxylamines. Further conversion of the N-hydroxylamine or N-hydroxyamide to reactive intermediates can occur in several ways, which include (i) esterification of the N-hydroxy group, (ii) non-enzymic protonation of the nitrogen of the hydroxylamine and (iii) oxidation to a free radical of arylhydroxamic acids. Following generation of such reactive electrophilic intermediates in tissues or cells, macromolecular binding has been observed to nucleic acids and proteins. In many cases, arylamidated and arylaminated products are formed with nucleic acid bases; in the case of the well-studied 2-acetylaminofluorene, nucleophilic atoms of guanine are the predominant site of reaction. Relatively little is known of the structure and biological consequences of DNA adducts formed from other aromatic amines, amides or nitro compounds; more research in these directions is warranted.

  8. Preparation of mesoporous aluminophosphate usingpoly(amido amine) as template

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xiaofeng; LIN Shen; CHEN Xinqing; CHEN Jiebo; YANG Liuyi; LUO Minghong

    2007-01-01

    Mesoporous aluminophosphate was prepared by using G4.0 poly(amido amine)dendrimer as a template and characterized by Fourier transform infrared spectrometer(FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM) and N2 adsorption/desorption methods.Results show that the title compound exhibits a typical mesoporous structure with the average pore size from 5 to 8 nm. The formation mechanism of the nanoporous structure using dendrimer as a template was also discussed.

  9. Synthesis Chiral Dihydropyridine Derivatives from Geniposide and Primary Amine

    Institute of Scientific and Technical Information of China (English)

    LIU Zhu-Lan; LEI Jun; LIU Jian-Li

    2003-01-01

    @@ Since Ohno and co-workers[1] reported the first example of asymmetric reduction using a model of coenzyme NADH in 1975, numerous efforts have been made to construct model compounds mimicking the activity of NADH and many publications have appeared. [2] Here we reported the design and synthesis of novel chiral dihydropyridine derivatives which can be used as NADH model from geniposide and primary amine.

  10. Cytocompatibility of amine functionalized carbon nanoparticles grafted on polyethylene.

    Science.gov (United States)

    Žáková, Pavlína; Slepičková Kasálková, Nikola; Kolská, Zdeňka; Leitner, Jindřich; Karpíšková, Jana; Stibor, Ivan; Slepička, Petr; Švorčík, Václav

    2016-03-01

    Five types of amide-amine Carbon Nano-Particles (CNPs) were prepared by functionalization of CNPs and characterized by several analytical methods. The successful grafting of amines on CNPs was verified by X-ray photoelectron spectroscopy (XPS), organic elemental analysis and electrokinetic analysis. The size and morphology of CNPs were determined from transmission electron microscopy. The surface area and porosity of CNPs were examined by adsorption and desorption isotherms. Differential scanning calorimetry was used to investigate thermal stability of CNPs. The amount of bonded amine depends on its dimensionality arrangement. Surface area and pore volumes of CNPs decrease several times after individual amino-compound grafting. Selected types of functionalized CNPs were grafted onto a plasma activated surface of HDPE. The successful grafting of CNPs on the polymer surface was verified by XPS. Wettability was determined by contact angle measurements. Surface morphology and roughness were studied by atomic force microscopy. A dramatic decrease of contact angle and surface morphology was observed on CNP grafted polymer surface. Cytocompatibility of modified surfaces was studied in vitro, by determination of adhesion, proliferation and viability of vascular smooth muscle cells (VSMCs). Grafting of CNPs onto the polymer surface has a positive effect on the adhesion, proliferation and viability of VSMCs.

  11. Robust dithiocarbamate-anchored amine functionalization of Au nanoparticles

    Science.gov (United States)

    Chen, Kai; Robinson, Hans D.

    2011-02-01

    We introduce an effective and facile technique that achieves robust amine functionalization of Au nanoparticles by binding the polyamine poly(allylamine hydrochloride) (PAH) to the surface using a dithiocarbamate (DTC) modification of the side group amines. The DTC anchor confers superior short- and long-term colloidal stability compared to a physisorbed layer of the same polymer. We also demonstrate that the surface amines are available for further functionalization and that at least four alternately charged polyelectrolyte layers can be assembled onto the particles. The latter modification could not be performed on a physisorbed functional layer, so this demonstrates the effectiveness of the DTC groups in robustly anchoring the polymer to the particle surface. At the same time, the DTC-anchored polymer layer is less than 2 nm thick in the dry state. This is one-third of the thickness of a physisorbed polyamine layer deposited under the same conditions, and sufficiently thin that the plasmonic field enhancement on the metal particle remains accessible to the outside environment. We attribute the difference in thickness to multiple DTC bonds on each polymer chain forcing it into much closer conformity to the particle surface than in the physisorbed case.

  12. Tris{2-[(2-aminobenzylideneamino]ethyl}amine

    Directory of Open Access Journals (Sweden)

    Perla Elizondo Martínez

    2010-12-01

    Full Text Available The title Schiff base, C27H33N7, is a tripodal amine displaying C3 symmetry, with the central tertiary N atom lying on the threefold crystallographic axis. The N—CH2—CH2—N conformation of the pendant arms is gauche [torsion angle = 76.1 (3°], which results in a claw-like molecule, with the terminal aniline groups wrapped around the symmetry axis. The lone pair of the apical N atom is clearly oriented inwards towards the cavity, and should thus be chemically inactive. The amine NH2 substituents lie in the plane of the benzene ring to which they are bonded. With such an arrangement, one amine H atom forms an S(6 motif through a weak N—H...N hydrogen bond with the imine N atom, while the other is engaged in an intermolecular N—H...π contact involving the benzene ring of a neighbouring molecule related by inversion. The benzene rings also participate in an intramolecular C—H...π contact of similar strength. In the crystal structure, molecules are separated by empty voids (ca 5% of the crystal volume, although the crystal seems to be unsolvated.

  13. Trace amine-associated receptors are olfactory receptors in vertebrates.

    Science.gov (United States)

    Liberles, Stephen D

    2009-07-01

    The mammalian nose is a powerful chemosensor, capable of detecting and distinguishing a myriad of chemicals. Sensory neurons in the olfactory epithelium contain two types of chemosensory G protein-coupled receptors (GPCRs): odorant receptors (ORs), which are encoded by the largest gene family in mammals, and trace amine-associated receptors (TAARs), a smaller family of receptors distantly related to biogenic amine receptors. Do TAARs play a specialized role in olfaction distinct from that of ORs? Genes encoding TAARs are found in diverse vertebrates, from fish to mice to humans. Like OR genes, each Taar gene defines a unique population of canonical sensory neurons dispersed in a single zone of the olfactory epithelium. Ligands for mouse TAARs include a number of volatile amines, several of which are natural constituents of mouse urine, a rich source of rodent social cues. One chemical, 2-phenylethylamine, is reported to be enriched in the urine of stressed animals, and two others, trimethylamine and isoamylamine, are enriched in male versus female urine. Furthermore, isoamylamine has been proposed to be a pheromone that induces puberty acceleration in young female mice. These data raise the possibility that some TAARs are pheromone receptors in the nose, a hypothesis consistent with recent data suggesting that the olfactory epithelium contains dedicated pheromone receptors, separate from pheromone receptors in the vomeronasal organ. Future experiments will clarify the roles of TAARs in olfaction.

  14. DFT investigation on dihydrogen-bonded amine-borane complexes.

    Science.gov (United States)

    Yan, Shihai; Zou, Hongmei; Kang, Wukui; Sun, Lixiang

    2016-01-01

    The DFT method has been employed in the exploration on dihydrogen-bonded amine-borane complexes, with a special emphasis on the dimerization and substituent group effect. Stable dihydrogen bonded complexes can be generated from these amine-borane monomers with the appearance of NH(δ+)…H(δ-)B interactions. The binding energy decreases gradually with the increase of the steric effect of the substituents. The substituent group number mainly varies the C-N bond length. The dimerization generates close H…H and influences predominantly the N-B distance. The effect of dimerization on IR and vibrational circular dichroism (VCD) spectra is stronger than that of the number of substituent groups, which leads to distinct NBO charge variation on α-C. Both the substituent group number and dimerization enhance the chemical shift difference between hydrogen atoms covalently bonded to N and B, Δδ H-H, which can be hired as an index for structural determination. It is proposed that amine-borane complexes with more substituent groups in higher degree of polymerization are potentially interesting materials for hydrogen storage. Graphical Abstract Both the number of substituent group and dimerization enhance the chemical shift difference of hydrogen atoms covalently bonded on N and B, Δδ H-H, which can be employed as an index for the structural determination.

  15. Role of specific amine surface configurations for grafted surfaces: implications for nanostructured CO2 adsorbents.

    Science.gov (United States)

    Shimizu, Steven; Song, Changsik; Strano, Michael

    2011-03-15

    Amine-grafted porous materials that capture CO2 from emission streams have been considered to be potential alternatives to the more energy-intensive liquid amine systems currently employed. An underappreciated fact in the uptake mechanism of these materials is that under dry, anhydrous conditions each CO2 molecule must react with two adjacent amine groups to adsorb onto the surface, which makes the configuration of amine groups on the surface critically important. Using this chemical mechanism, we developed a semiempirical adsorption isotherm equation that allows straightforward computation of the adsorption isotherm from an arbitrary surface configuration of grafted amines for honeycomb, square, and triangular lattices. The model makes use of the fact that the distribution of amines with respect to the number of nearest neighbors, referred to as the z-histogram, along with the amine loading and equilibrium constant, uniquely determine the adsorption characteristics to a very good approximation. This model was used to predict the range of uptakes possible just through surface configuration, and it was used to fit experimental data in the literature to give a meaningful equilibrium constant and show how efficiently amines were utilized. We also demonstrate how the model can be utilized to design more efficient nanostructured adsorbents and polymer-based adsorbents. Recommendations for exploiting the role of surface configuration include the use of linear instead of branched polyamines, higher amine grafting densities, the use of flexible, less bulky, long, and rotationally free amine groups, and increased silanol densities.

  16. A Review: Microbiological, Physicochemical and Health Impact of High Level of Biogenic Amines in Fish Sauce

    Directory of Open Access Journals (Sweden)

    Muhammad Z. Zaman

    2009-01-01

    Full Text Available Problem statement: Biogenic amines are basic nitrogenous compounds present in a wide variety of foods and beverages. Their formations were mainly due to the amino acids decarboxylase activity of certain microorganisms. Excessive intake of biogenic amines could induce many undesirable physiological effects determined by their psychoactive and vasoactive action. Fish sauce which is considered as a good source of dietary protein, amino acids, vitamins and minerals was a popular condiment in Southeast Asian countries. However, it has also been reported that fish sauce contain high amount of amines. Hence, attention should be given to ensure the safety of this product. Approach: A review study was conducted to deliver an overview on the presence of biogenic amines in fish sauce and to discuss the important factors affecting their accumulation. Impact of amines on human health and efforts to reduce their accumulation in fish sauce were also discussed to give a comprehensive view. Results: Histamine, putrescine and cadaverine is the most abundant amines in fish sauce with maximum reported value of 1220, 1257 and 1429 ppm, respectively. Tyramine present in a lesser amount with maximum reported value of 1178 ppm. Other amines such as tryptamine, phenylethylamine, spermine and spermidine were considered as minor amines. However, different profiles of amines were reported in different type of products. This was depended on microbial flora, availability of precursors and physicochemical factors such as temperature, pH, salt, oxygen and sugar concentration. In synergistically supporting physicochemical factors, several microorganisms such as Enterobacteriaceae, Micrococci and Lactobacilli were responsible for biogenic amines formation in fish sauce. Conclusion: Since the formation of amines in fish sauce was a result of many factors, it was almost virtually impossible to control each factor during fermentation. Addition of amines degrading bacteria into fish

  17. Equilibrium and Transport Properties of Primary, Secondary and Tertiary Amines by Molecular Simulation

    Directory of Open Access Journals (Sweden)

    Orozco Gustavo A.

    2014-09-01

    Full Text Available Using molecular simulation techniques such as Monte Carlo (MC and molecular dynamics (MD, we present several simulation results of thermodynamic and transport properties for primary, secondary and tertiary amines. These calculations are based on a recently proposed force field for amines that follows the Anisotropic United Atom approach (AUA. Different amine molecules have been studied, including n-ButylAmine, di-n-ButylAmine, tri-n-ButylAmine and 1,4-ButaneDiAmine for primary, secondary, tertiary and multi-functional amines respectively. For the transport properties, we have calculated the viscosity coefficients as a function of temperature using the isothermal-isobaric (NPT ensemble. In the case of the pure components, we have investigated different thermodynamic properties using NVT Gibbs ensemble simulations such as liquid-vapor phase equilibrium diagrams, vaporization enthalpies, vapor pressures, normal boiling points, critical temperatures and critical densities. We have also calculated the excess enthalpies for water-n-ButylAmine and n-heptane-n-ButylAmine mixtures using Monte Carlo simulations in the NPT ensemble. In addition, we present the calculation of liquid-vapor surface tensions of n-ButylAmine using a two-phase NVT simulation as well as the radial distribution functions. Finally, we have investigated the physical Henry constants of nitrous oxide (N2O and nitrogen (N2 in an aqueous solutions of n-ButylAmine. In general, we found a good agreement between the available experimental information and our simulation results for all the studied properties, ratifying the predictive capability of the AUA force field for amines.

  18. From caffeine to fish waste: amine compounds present in food and drugs and their interactions with primary amine oxidase.

    LENUS (Irish Health Repository)

    Olivieri, Aldo

    2011-07-01

    Tissue bound primary amine oxidase (PrAO) and its circulating plasma-soluble form are involved, through their catalytic activity, in important cellular roles, including the adhesion of lymphocytes to endothelial cells during various inflammatory conditions, the regulation of cell growth and maturation, extracellular matrix deposition and maturation and glucose transport. PrAO catalyses the oxidative deamination of several xenobiotics and has been linked to vascular toxicity, due to the generation of cytotoxic aldehydes. In this study, a series of amines and aldehydes contained in food and drugs were tested via a high-throughput assay as potential substrates or inhibitors of bovine plasma PrAO. Although none of the compounds analyzed were found to be substrates for the enzyme, a series of molecules, including caffeine, the antidiabetics phenformin and tolbutamide and the antimicrobial pentamidine, were identified as PrAO inhibitors. Although the inhibition observed was in the millimolar and micromolar range, these data show that further work will be necessary to elucidate whether the interaction of ingested biogenic or xenobiotic amines with PrAO might adversely affect its biological roles.

  19. Sponges with covalently tethered amines for high-efficiency carbon capture

    KAUST Repository

    Qi, Genggeng

    2014-12-12

    © 2014 Macmillan Publishers Limited. All rights reserved. Adsorption using solid amine sorbents is an attractive emerging technology for energy-efficient carbon capture. Current syntheses for solid amine sorbents mainly based on physical impregnation or grafting-to methods (for example, aminosilane-grafting) lead to limited sorbent performance in terms of stability and working capacity, respectively. Here we report a family of solid amine sorbents using a grafting-from synthesis approach and synthesized by cationic polymerization of oxazolines on mesoporous silica. The sorbent with high amount of covalently tethered amines shows fast adsorption rate, high amine efficiency and sorbent capacity well exceeding the highest value reported to date for lowerature carbon dioxide sorbents under simulated flue gas conditions. The demonstrated efficiency of the new amine-immobilization chemistry may open up new avenues in the development of advanced carbon dioxide sorbents, as well as other nitrogen-functionalized systems.

  20. Conversion of alcohols to enantiopure amines through dual enzyme hydrogen-borrowing cascades

    Science.gov (United States)

    Mutti, Francesco G.; Knaus, Tanja; Scrutton, Nigel S.; Breuer, Michael; Turner, Nicholas J.

    2016-01-01

    α-Chiral amines are key intermediates for the synthesis of a plethora of chemical compounds on industrial scale. Here we present a biocatalytic hydrogen-borrowing amination of primary and secondary alcohols that allows for the efficient and environmentally benign production of enantiopure amines. The method relies on the combination of an alcohol dehydrogenase (ADHs from Aromatoleum sp., Lactobacillus sp. and Bacillus sp.) enzyme operating in tandem with an amine dehydrogenase (AmDHs engineered from Bacillus sp.) to aminate a structurally diverse range of aromatic and aliphatic alcohols (up to 96% conversion and 99% enantiomeric excess). Furthermore, primary alcohols are aminated with high conversion (up to 99%). This redox self-sufficient network possesses high atom efficiency, sourcing nitrogen from ammonium and generating water as the sole by-product. PMID:26404833

  1. Conversion of alcohols to enantiopure amines through dual-enzyme hydrogen-borrowing cascades.

    Science.gov (United States)

    Mutti, Francesco G; Knaus, Tanja; Scrutton, Nigel S; Breuer, Michael; Turner, Nicholas J

    2015-09-25

    α-Chiral amines are key intermediates for the synthesis of a plethora of chemical compounds at industrial scale. We present a biocatalytic hydrogen-borrowing amination of primary and secondary alcohols that allows for the efficient and environmentally benign production of enantiopure amines. The method relies on a combination of two enzymes: an alcohol dehydrogenase (from Aromatoleum sp., Lactobacillus sp., or Bacillus sp.) operating in tandem with an amine dehydrogenase (engineered from Bacillus sp.) to aminate a structurally diverse range of aromatic and aliphatic alcohols, yielding up to 96% conversion and 99% enantiomeric excess. Primary alcohols were aminated with high conversion (up to 99%). This redox self-sufficient cascade possesses high atom efficiency, sourcing nitrogen from ammonium and generating water as the sole by-product.

  2. A facile protocol for N-Cbz protection of amines in PEG-600

    Institute of Scientific and Technical Information of China (English)

    Chun Lin Zhang; Dong Feng Zhang; Hong Yi Zhao; Zi Yun Lin; Hai Hong Huang

    2012-01-01

    An efficient and eco-friendly protocol for the chemoselective N-benzyloxycarbonylation of amines was described.The reaction of amines with benzyl chloroformate (Cbz-Cl) in the presence of PEG-600 at room temperature afforded the corresponding N-Cbz derivatives in excellent yields.The method is applicable to the N-Cbz protection of aliphatic (acyclic and cyclic) and aromatic amines.

  3. Monofunctional primary amine: A new class of organocatalyst for asymmetric Aldol reaction

    Indian Academy of Sciences (India)

    KHIANGTE VANLALDINPUIA; PORAG BORA; GHANASHYAM BEZ

    2017-03-01

    A new class of organocatalysts involving a primary amine as the only functional group is developed for catalytic asymmetric aldol reaction of cyclohexanone/ cyclopentanone with various aryl aldehydes in thepresence of benzoic acid as an additive at −10◦C. In an unexpected observation, the primary amine catalyzed reactions gave excellent yield and good to excellent stereoselectivity, while secondary amines were found to have little or no reactivity under similar reaction conditions.

  4. Tri-n-butylphosphane catalyzed ring opening of aziridines with secondary amines

    Institute of Scientific and Technical Information of China (English)

    Wan Xuan Zhang; Li Su; Wei Gang Hu; Jie Zhou

    2012-01-01

    Ring opening of aziridine with dialkyl amine took place readily in the presence of catalytic amounts of tri-n-butylphosphane (10 mol%) in the mixture of CH3CN/H2O (10:1),giving corresponding vicinal diamines in mediate to high yields (58-95%) with good regioselecfivifie,while aromatic secondary amine could not react under the same condifions.Tti-n-butylphosphane exhibited different catalytic selectivity to amines from Lewis acid catalysts.

  5. Mechanistic insights into the oxidative dehydrogenation of amines to nitriles in continuous flow

    DEFF Research Database (Denmark)

    Corker, Emily C.; Ruiz-Martínez, Javier; Riisager, Anders;

    2015-01-01

    The oxidative dehydrogenation of various aliphatic amines to their corresponding nitrile compounds using RuO2/Al2O3 catalysts in air was successfully applied to a continuous flow reaction. Conversions of amines (up to >99%) and yields of nitriles (up to 77%) varied depending on reaction conditions...... and the amine utilised. The presence of water was found to be important for the activity and stability of the RuO2/Al2O3 catalyst. The Hammett relationship and in situ infrared spectroscopy were applied to divulge details about the catalytic mechanism of the oxidative dehydrogenation of amines over RuO2/Al2O3...

  6. Amine-Functionalized ZnO Nanosheets for Efficient CO2 Capture and Photoreduction

    Directory of Open Access Journals (Sweden)

    Yusen Liao

    2015-10-01

    Full Text Available Amine-functionalized ZnO nanosheets were prepared through a one-step hydrothermal method by using monoethanolamine, which has a hydroxyl group, for covalent attachment on ZnO and a primary amine group to supply the amine-functionalization. We demonstrate that the terminal amine groups on ZnO surfaces substantially increase the capability of CO2 capture via chemisorption, resulting in effective CO2 activation. As a result, the photogenerated electrons from excited ZnO can more readily reduce the surface-activated CO2, which thereby enhances the activity for photocatalytic CO2 reduction.

  7. Amine-Functionalized ZnO Nanosheets for Efficient CO2 Capture and Photoreduction

    OpenAIRE

    Yusen Liao; Zhaoning Hu; Quan Gu; Can Xue

    2015-01-01

    Amine-functionalized ZnO nanosheets were prepared through a one-step hydrothermal method by using monoethanolamine, which has a hydroxyl group, for covalent attachment on ZnO and a primary amine group to supply the amine-functionalization. We demonstrate that the terminal amine groups on ZnO surfaces substantially increase the capability of CO2 capture via chemisorption, resulting in effective CO2 activation. As a result, the photogenerated electrons from excited ZnO can more readily reduce t...

  8. Control of biogenic amines in fermented sausages: role of starter cultures

    Directory of Open Access Journals (Sweden)

    Mariluz eLatorre-Moratalla

    2012-05-01

    Full Text Available Biogenic amines show biological activity and exert undesirable physiological effects when absorbed at high concentrations. Biogenic amines are mainly formed by microbial decarboxylation of amino acids and thus are usually present in a wide range of foods, fermented sausages being one of the major biogenic amine sources. The use of selected starter cultures is one of the best technological measures to control aminogenesis during meat fermentation. Although with variable effectiveness, several works show the ability of some starters to render biogenic amine-free sausages. In this paper, the effect of different starter culture is reviewed and the factors determining their performance discussed.

  9. Control of biogenic amines in fermented sausages: role of starter cultures.

    Science.gov (United States)

    Latorre-Moratalla, M L; Bover-Cid, Sara; Veciana-Nogués, M T; Vidal-Carou, M C

    2012-01-01

    Biogenic amines show biological activity and exert undesirable physiological effects when absorbed at high concentrations. Biogenic amines are mainly formed by microbial decarboxylation of amino acids and thus are usually present in a wide range of foods, fermented sausages being one of the major biogenic amine sources. The use of selected starter cultures is one of the best technological measures to control aminogenesis during meat fermentation. Although with variable effectiveness, several works show the ability of some starters to render biogenic amine-free sausages. In this paper, the effect of different starter culture is reviewed and the factors determining their performance discussed.

  10. Chemical and Molecular Descriptors for the Reactivity of Amines with CO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Anita S.; Kitchin, John R.

    2012-10-24

    Amine-based solvents are likely to play an important role in CO{sub 2} capture applications in the future, and the identification of amines with superior performance will facilitate their use in CO{sub 2} capture. While some improvements in performance will be achieved through process modifications, modifying the CO{sub 2} capture performance of an amine also implies in part an ability to modify the reactions between the amine and CO{sub 2} through development of new functionalized amines. We present a computational study of trends in the reactions between CO{sub 2} and functionalized amines with a focus on identifying molecular descriptors that determine trends in reactivity. We examine the formation of bicarbonate and carbamate species on three classes of functionalized amines: alkylamines, alkanolamines, and fluorinated alkylamines including primary, secondary and tertiary amines in each class. These functional groups span electron-withdrawing to donating behavior, hydrogen-bonding, extent of functionalization, and proximity effects of the functional groups. Electron withdrawing groups tend to destabilize CO{sub 2} reaction products, whereas electron-donating groups tend to stabilize CO{sub 2} reaction products. Hydrogen bonding stabilizes CO{sub 2} reaction products. Electronic structure descriptors based on electronegativity were found to describe trends in the bicarbonate formation energy. A chemical correlation was observed between the carbamate formation energy and the carbamic acid formation energy. The local softness on the reacting N in the amine was found to partially explain trends carbamic acid formation energy.

  11. Method of neutralizing the corrosive surface of amine-cured epoxy resins

    Science.gov (United States)

    Lee, S. Y. (Inventor)

    1982-01-01

    The corrosive alkaline surface layer of an epoxy resin product formed by the curing of the epoxy with an aliphatic amine is eliminated by first applying a non-solvent to remove most or all of the free unreacted amine and then applying a layer of a chemical reagent to neutralize the unused amine or amine functional groups by forming a substituted urea. The surface then may be rinsed with acetone and then with alcohol. The non-solvent may be an alcohol. The neutralizing chemical reagent is a mono-isocyanate or a mono-isothiocyanate. Preferred is an aromatic mono-isocyanate such as phenyl isocyanate, nitrophenyl isocyanate and naplthyl isocyanate.

  12. EFFECTS OF HYDRAZINES ON THE METABOLISM OF CERTAIN AMINES AND AMINO ACIDS.

    Science.gov (United States)

    AMINES, * AMINO ACIDS , *DIAMINE OXIDASE, TOXICITY, METABOLISM, METABOLISM, DIMETHYLHYDRAZINES, GLUTAMIC ACID, ENZYMES, PHARMACOLOGY, TRACER STUDIES, LABELED SUBSTANCES, RESPIRATION, GASTROINTESTINAL SYSTEM, RATS.

  13. The roles of dihydrogen bonds in amine borane chemistry.

    Science.gov (United States)

    Chen, Xuenian; Zhao, Ji-Cheng; Shore, Sheldon G

    2013-11-19

    A dihydrogen bond (DHB) is an electrostatic interaction between a protonic hydrogen and a hydridic hydrogen. Over the past two decades, researchers have made significant progress in the identification and characterization of DHBs and their properties. In comparison with conventional hydrogen bonds (HBs), which have been widely used in catalysis, molecular recognition, crystal engineering, and supramolecular synthesis, chemists have only applied DHBs in very limited ways. Considering that DHBs and conventional HBs have comparable strength, DHBs could be more widely applied in chemistry. Over the past several years, we have explored the impact of DHBs on amine borane chemistry and the syntheses and characterization of amine boranes and ammoniated metal borohydrides for hydrogen storage. Through systematic computational and experimental investigations, we found that DHBs play a dominant role in dictating the reaction pathways (and thus different products) of amine boranes where oppositely charged hydrogens coexist for DHB formation. Through careful experiments, we observed, for the first time, a long-postulated reaction intermediate, ammonia diborane (AaDB), whose behavior is essential to mechanistic understanding of the formation of the diammoniate of diborane (DADB) in the reaction of ammonia (NH3) with tetrahydrofuran borane (THF·BH3). The formation of DADB has puzzled the boron chemistry community for decades. Mechanistic insight enabled us to develop facile syntheses of aminodiborane (ADB), ammonia borane (AB), DADB, and an inorganic butane analog NH3BH2NH2BH3 (DDAB). Our examples, together with those in the literature, reinforce the fact that DHB formation and subsequent molecular hydrogen elimination are a viable approach for creating new covalent bonds and synthesizing new materials. We also review the strong effects of DHBs on the stability of conformers and the hydrogen desorption temperatures of boron-nitrogen compounds. We hope that this Account will

  14. Lactoperoxidase-catalyzed activation of carcinogenic aromatic and heterocyclic amines.

    Science.gov (United States)

    Gorlewska-Roberts, Katarzyna M; Teitel, Candee H; Lay, Jackson O; Roberts, Dean W; Kadlubar, Fred F

    2004-12-01

    Lactoperoxidase, an enzyme secreted from the human mammary gland, plays a host defensive role through antimicrobial activity. It has been implicated in mutagenic and carcinogenic activation in the human mammary gland. The potential role of heterocyclic and aromatic amines in the etiology of breast cancer led us to examination of the lactoperoxidase-catalyzed activation of the most commonly studied arylamine carcinogens: 2-amino-1-methyl-6-phenylimidazo[4,5-b]-pyridine (PhIP), benzidine, 4-aminobiphenyl (ABP), 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), and 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx). In vitro activation was performed with lactoperoxidase (partially purified from bovine milk or human milk) in the presence of hydrogen peroxide and calf thymus DNA. Products formed during enzymatic activation were monitored by HPLC with ultraviolet and radiometric detection. Two of these products were characterized as hydrazo and azo derivatives by means of mass spectrometry. The DNA binding level of 3H- and 14C-radiolabeled amines after peroxidase-catalyzed activation was dependent on the hydrogen peroxide concentration, and the highest levels of carcinogen binding to DNA were observed at 100 microM H2O2. Carcinogen activation and the level of binding to DNA were in the order of benzidine > ABP > IQ > MeIQx > PhIP. One of the ABP adducts was identified, and the level at which it is formed was estimated to be six adducts/10(5) nucleotides. The susceptibility of aromatic and heterocyclic amines for lactoperoxidase-catalyzed activation and the binding levels of activated products to DNA suggest a potential role of lactoperoxidase-catalyzed activation of carcinogens in the etiology of breast cancer.

  15. Preparation of heterocyclic amines by an oxidative amination of zinc organometallics mediated by Cu(I): a new oxidative cycloamination for the preparation of annulated indole derivatives.

    Science.gov (United States)

    Kienle, Marcel; Wagner, Andreas J; Dunst, Cora; Knochel, Paul

    2011-02-01

    Functionalized heterocyclic zinc reagents are easily aminated by an oxidative amination reaction of zinc amidocuprates prepared from various lithium amides. For the oxidation step, PhI(OAc)(2) proved to be the best reagent. The required heterocyclic zinc organometallics can be prepared either by direct metalation, by magnesium insertion in the presence of ZnCl(2), or by transmetalation of a suitable magnesium reagent. Furthermore, we report a new ring-closing reaction involving an intramolecular oxidative amination reaction. This reaction allows the preparation of tetracyclic heterocycles containing furan, thiophene, or indole rings.

  16. [N-Benzyl-N-(diphenylphosphanylmethylpyridin-2-amine]chloridomethylplatinum(II

    Directory of Open Access Journals (Sweden)

    Chong-Qing Wan

    2011-01-01

    Full Text Available In the mononuclear title complex, [Pt(CH3Cl(C25H23N2P], the N-benzyl-N-(diphenylphosphanylmethylpyridin-2-amine functions as a bidentate ligand with the pyridyl N atom and the phosphine P atom chelating the PtII ion, forming a six-membered metallocycle. The PtII atom adopts a square-planar coordination geometry with one methyl group and one chloride ligand bonding to the metal center in a cis relationship. C—H...π and C—H...Cl interactions help to consolidate the packing.

  17. Relationship between Structures and Carcinogenicities of Heterocyclic Amines

    Institute of Scientific and Technical Information of China (English)

    JU Xue-hai; DAI Qian-huan; CHEN Sha; WANG Wen-jun

    2004-01-01

    Semi-empirical molecular orbital calculations were performed on heterocyclic aromatic amines(HCAs). The relationship between the structures and the carcinogenicities can be rationally elucidated by the models based on the metabolism of HCAs and the Di-region theory. The degree of easiness for the formation of Di-region electrophilic centers determines the carcinogenic activity. There is a good linear relationship between the observed carcinogenicities and the PM3 calculated parameters, with r=0.973 and F=29.8>(F*0.*01).

  18. Preparation of amine coated silver nanoparticles using triethylenetetramine

    Indian Academy of Sciences (India)

    L Ramajo; R Parra; M Reboredo; M Castro

    2009-01-01

    This article presents a simple method towards the preparation of functionalized silver nanoparticles in a continuous medium. Silver nanoparticles were obtained through AgNO3 chemical reduction in ethanol and triethylenetetramine was used to stabilize and functionalize the metal. The product was characterized with X-ray diffraction (XRD), Fourier-transformed infrared spectroscopy (FTIR), UVvisible spectroscopy, thermal gravimetric analysis (TGA) and transmission electron microscopy (TEM). Monocrystalline silver particles with cubic structure and an average size of 20 nm were obtained. The results reveal that it is possible to synthesize Ag nanoparticles functionalized with amine groups and that particle size is influenced by the processing route.

  19. The repertoire of trace amine G-protein-coupled receptors

    DEFF Research Database (Denmark)

    Gloriam, David E.; Bjarnadóttir, Thóra K; Yan, Yi-Lin

    2005-01-01

    Trace amines, such as tyramine, beta-phenylethylamine, tryptamine, and octopamine, are present in trace levels in nervous systems and bind a specific family of G-protein-coupled receptors (GPCR), but the function or origin of this system is not well understood. We searched the genomes of several ...... ancestor of vertebrate TA-receptors arose before the split of the ray-finned and lobe-finned fishes. The evolutionary history of the TA-receptors is more complex than for most other GPCR families and here we suggest a mechanism by which they may have arisen....

  20. Extraction of beryllium sulfate by a long chain amine; Extraction du sulfate de beryllium par une amine a longue chaine

    Energy Technology Data Exchange (ETDEWEB)

    Etaix, E.S. [Commissariat a l' Energie Atomique, Fontenay-Aux-Roses (France). Centre d' Etudes Nucleaires

    1968-06-01

    The extraction of sulfuric acid in aqueous solution by a primary amine in benzene solution, 3-9 (diethyl) - 6-amino tri-decane (D.E.T. ) - i.e., with American nomenclature 1-3 (ethyl-pentyl) - 4-ethyl-octyl amine (E.P.O.) - has made it possible to calculate the formation constants of alkyl-ammonium sulfate and acid sulfate. The formula of the beryllium and alkyl-ammonium sulfate complex formed in benzene has next been determined, for various initial acidity of the aqueous solution. Lastly, evidence has been given of negatively charged complexes of beryllium and sulfate in aqueous solution, through the dependence of the aqueous sulfate ions concentration upon beryllium extraction. The formation constant of these anionic complexes has been evaluated. (author) [French] L'etude de l'extraction de l'acide sulfurique en solution aqueuse par une amine primaire en solution dans le benzene, le diethyl-3,9 amino-6 tridecane (D.E.T.) - autre nom americain 1-3 (ethylpentyl) - 4-ethyloctylamine (E.P.O.) a permis de calculer les constantes de formation du sulfate et de l'hydrogenosulfate d'alkyl-ammonium. La formule du complexe de sulfate de beryllium et d'alkyl-ammonium forme en solution benzenique a ete ensuite determinee pour diverses acidites initiales de la solution aqueuse. Enfin, l'influence de la concentration des ions sulfate de la phase aqueuse sur l'extraction du beryllium a mis en evidence la formation en solution aqueuse de complexes anioniques de sulfate et de beryllium dont la constante de formation a ete evaluee. (auteur)

  1. Technological factors affecting biogenic amine content in foods: a review

    Directory of Open Access Journals (Sweden)

    Fausto Gardini

    2016-08-01

    Full Text Available Biogenic amines (BAs are molecules which can be present in foods and, due to their toxicity, can cause adverse effects on the consumers. BAs are generally produced by microbial decarboxylation of amino acids in food products. The most significant BAs occurring in foods are histamine, tyramine, putrescine, cadaverine, tryptamine, 2-phenylethylamine, spermine, spermidine and agmatine. The importance of preventing the excessive accumulation of BAs in food is related to their impact on human health and food quality. Quality criteria in connection with the presence of BAs in food and food products are necessary from a toxicological point of view. This is particularly important in fermented foods in which the massive microbial proliferation required for obtaining specific products is often relater with BA accumulation. In this review, up-to-date information and recent discoveries about technological factors affecting biogenic amine content in foods are reviewed. Specifically, BA forming-microorganism and decarboxylation activity, genetic and metabolic organization of decarboxylases, risk associated to BAs (histamine, tyramine toxicity and other BAs, environmental factors influencing BA formation (temperature, salt concentration, pH. In addition, the technological factors for controlling BA production (use of starter culture, technological additives, effects of packaging, other non-thermal treatments, metabolising BA by microorganisms, effects of pressure treatments on BA formation and antimicrobial substances are addressed.

  2. BIODEGRADATION OF AROMATIC AMINE COMPOUNDS USING MOVING BED BIOFILM REACTORS

    Directory of Open Access Journals (Sweden)

    M. Delnavaz ، B. Ayati ، H. Ganjidoust

    2008-10-01

    Full Text Available Three moving bed biofilm reactors were used to treat synthesized wastewater of aromatic amine compounds including aniline, para-diaminobenzene and para-aminophenol that are found in many industrial wastewaters. The reactors with cylindrical shape had an internal diameter and an effective depth of 10 and 60 cm, respectively. The reactors were filled with light expanded clay aggregate as carriers and operated in an aerobic batch and continuous conditions. Evaluation of the reactors' efficiency was done at different retention time of 8, 24, 48 and 72 h with an influent COD from 100 to 3500 mg/L (filling ratio of 50%. The maximum obtained removal efficiencies were 90% (influent COD=2000 mg/L, 87% (influent COD=1000 mg/L and 75% (influent COD=750 mg/L for aniline, para-diaminobenzene and para-aminophenol, respectively. In the study of decrease in filling ratio from 50 to 30 percent, 6% decrease for both para-diaminobenzene and para-aminophenol and 7% increase for aniline degradation were obtained. The removal efficiency was decreased to about 10% after 15 days of continuous loading for each of the above three substrates. In the shock loading test, initially the COD removal rate was decreased in all reactors, but after about 10 days, it has been approached to the previous values. Finally, biodegradability of aromatic amines has been proved by nuclear magnetic resonance system.

  3. Amine-oxide hybrid materials for acid gas separations

    KAUST Repository

    Bollini, Praveen

    2011-01-01

    Organic-inorganic hybrid materials based on porous silica materials functionalized with amine-containing organic species are emerging as an important class of materials for the adsorptive separation of acid gases from dilute gas streams. In particular, these materials are being extensively studied for the adsorption of CO 2 from simulated flue gas streams, with an eye towards utilizing these materials as part of a post-combustion carbon capture process at large flue gas producing installations, such as coal-fired electricity-generating power plants. In this Application Article, the utilization of amine-modified organic-inorganic hybrid materials is discussed, focusing on important attributes of the materials, such as (i) CO 2 adsorption capacities, (ii) adsorption and desorption kinetics, and (iii) material stability, that will determine if these materials may one day be useful adsorbents in practical CO 2 capture applications. Specific research needs and limitations associated with the current body of work are identified. © 2011 The Royal Society of Chemistry.

  4. Analysis of Some Biogenic Amines by Micellar Liquid Chromatography

    Directory of Open Access Journals (Sweden)

    Irena Malinowska

    2012-01-01

    Full Text Available Micellar liquid chromatography (MLC with the use of high performance liquid chromatography (HPLC was used to determine some physicochemical parameters of six biogenic amines: adrenaline, dopamine, octopamine, histamine, 2-phenylethylamine, and tyramine. In this paper, an influence of surfactant’s concentration and pH of the micellar mobile phase on the retention of the tested substances was examined. To determine the influence of surfactant’s concentration on the retention of the tested amines, buffered solutions (at pH 7.4 of ionic surfactant—sodium dodecyl sulfate SDS (at different concentrations with acetonitrile as an organic modifier (0.8/0.2 v/v were used as the micellar mobile phases. To determine the influence of pH of the micellar mobile phase on the retention, mobile phases contained buffered solutions (at different pH values of sodium dodecyl sulfate SDS (at 0.1 M with acetonitrile (0.8/0.2 v/v. The inverse of value of retention factor (1/ versus concentration of micelles ( relationships were examined. Other physicochemical parameters of solutes such as an association constant analyte—micelle (ma—and partition coefficient of analyte between stationary phase and water (hydrophobicity descriptor (swΦ were determined by the use of Foley’s equation.

  5. Application of ultraviolet, ozone, and advanced oxidation treatments to washwaters to destroy nitrosamines, nitramines, amines, and aldehydes formed during amine-based carbon capture.

    Science.gov (United States)

    Shah, Amisha D; Dai, Ning; Mitch, William A

    2013-03-19

    Although amine-based CO(2) absorption is a leading contender for full-scale postcombustion CO(2) capture at power plants, concerns have been raised about the potential release of carcinogenic N-nitrosamines and N-nitramines formed by reaction of exhaust gas NO(x) with the amines. Experiments with a laboratory-scale pilot unit suggested that washwater units meant to scrub contaminants from absorber unit exhaust could potentially serve as a source of N-nitrosamines via reactions of residual NO(x) with amines accumulating in the washwater. Dosage requirements for the continuous treatment of the washwater recycle line with ultraviolet (UV) light for destruction of N-nitrosamines and N-nitramines, and with ozone or hydroxyl radical-based advanced oxidation processes (AOPs) for destruction of amines and aldehydes, were evaluated. Although capture synergies between UV and ozone treatments.

  6. Electron beam induced electronic transport in alkyl amine-intercalated VOx nanotubes

    NARCIS (Netherlands)

    O'Dwyer, C.; Lavayen, V.; Clavijo-Cedeno, C.; Sotomayor Torres, C.M.

    2008-01-01

    The electron beam induced electronic transport in primary alkyl amine-intercalated V2O5 nanotubes is investigated where the organic amine molecules are employed as molecular conductive wires to an aminosilanized substrate surface and contacted to Au interdigitated electrode contacts. The results dem

  7. Solid-phase Synthesis of a Novel Kind of Hydroxylated Heterocyclic Ketene Aminals

    Institute of Scientific and Technical Information of China (English)

    Tao PENG; Chu Yi YU; Zhi Tang HUANG

    2006-01-01

    An efficient solid-phase synthesis method for novel heterocyclic ketene aminals containing a hydroxyl group has been developed. The loading of the substrate on the resin through the hydroxyl group and the protection of the amine by the Schiff base were the key steps in the synthesis.

  8. Emissions, sinks and gas to particle conversion of amines and ammonia

    Science.gov (United States)

    Lee, S.

    2015-12-01

    Nitrogen-containing base compounds, amines and ammonia, play important roles in formation of secondary aerosols in the atmosphere, but their sources, sinks and atmospheric transformation processes are not well understood. Also, there are very limited analytical methods that are capable of measuring pptv or sub-pptv level of amines and ammonia. We have developed a chemical ionization mass spectrometer (CIMS) that can detect amines and ammonia at the pptv and sub-pptv level with a 1 min of integration time. Here, we report ambient measurements of amines and ammonia made in a moderately polluted continental site (Kent, Ohio) and in a rural Southeastern U.S. forest (Centreville, Alabama). Our finding indicate that there are much more abundant gas phase amines (C1-C6) and ammonia in the polluted site than in the rural forest, highlighting the importance of constraining anthropogenic emission sources of amines. At both locations, concentrations of these base compounds show clear temperature dependence, indicating strong gas-to-particle conversion processes. Compared to ammonia, amines can partition into aerosol phases even more effectively due to lower saturation vapor pressures. Measurements in the clean rural forest show that transported biomass burning plumes are the major source of amines. These nitrogen-containing compounds effectively undergo wet deposition in the atmosphere due to high solubilities.

  9. Protecting-group-free amination of halogenated nitrobenzaldehyde with palladium catalyst

    Institute of Scientific and Technical Information of China (English)

    Jing Cao; Jun Xiang Feng; Yong Xiang Wu; Ya Ya Tuo

    2010-01-01

    One-step method for the synthesis of secondary aliphatic amine substituted nitrobenzaldehyde was developed.In the presence of Pd catalyst,halogenated nitrobenzaldehyde could be smoothly coupled with secondary aliphatic amine to give the target product in hexamethylphosphamide (HMPT) media without the protection of aldehyde groups.

  10. N-heterocyclic carbene copper(I) catalysed N-methylation of amines using CO2

    KAUST Repository

    Santoro, Orlando

    2015-09-30

    The N-methylation of amines using CO2 and PhSiH3 as source of CH3 was efficiently performed using a N-heterocyclic carbene copper(I) complex. The methodology was found compatible with aromatic and aliphatic primary and secondary amines. Synthetic and computational studies have been carried out to support the proposed reaction mechanism for this transformation.

  11. A protocol for amide bond formation with electron deficient amines and sterically hindered substrates

    DEFF Research Database (Denmark)

    Due-Hansen, Maria E; Pandey, Sunil K; Christiansen, Elisabeth;

    2016-01-01

    A protocol for amide coupling by in situ formation of acyl fluorides and reaction with amines at elevated temperature has been developed and found to be efficient for coupling of sterically hindered substrates and electron deficient amines where standard methods failed....

  12. Cine and direct aminations of 5- and 6-halogeno-pyrimidines. A mechanistic study

    NARCIS (Netherlands)

    Rasmussen, C.A.H.

    1978-01-01

    This thesis describes investigations into the mechanistic aspects of the cine amination of 4-substituted 5-halogenopyrimidines and the direct amination of 4-substituted 6-halogenopyrimidines by potassium amide in liquid ammonia.PMR spectra of some 4-R-5-bromopyrimidines (R=C 6

  13. CZE study on adsorption processes of aliphatic and aromatic amines on PMMA chip.

    Science.gov (United States)

    Masár, Marián; Kruk, Pavol; Luc, Milan; Bodor, Róbert; Danč, Ladislav; Troška, Peter

    2013-02-01

    Adsorption processes on a PMMA chip linked with CZE separations of a group of 13 aliphatic and aromatic mono- and di-amines were studied. Due to the lack of chromophores within aliphatic amines, contact conductivity detection implemented directly onto the chip was used for monitoring of cationic CZE separations. To prevent an adsorption of studied amines to the chip channels, the surface of PMMA chip was modified by dynamic coating. Different surface modifiers, such as aliphatic oligoamines (diethylenetriamine and triethylenetetramine), were added to the BGE solutions filling the chip channels. The effect of various concentrations of surface modifiers on peak profiles and separation parameters of amines was monitored. Of these, mainly, aliphatic di-amines and aromatic mono-amines adversely affected the CZE resolution of a whole group of analytes by their strong adsorption to the chip channels. A propionate BGE with pH 3.2 containing 100 μM triethylenetetramine and 25 mM 18-crown-6-ether was found suitable for CZE resolution of 12 from a total of 13 amines studied. Simple dynamic modification of the surface of PMMA chip enabled fast (analysis time lasted 9 min), sensitive (sub-μM LODs reached) and reproducible (1-3% RSD of the peak areas) CZE analysis of the aliphatic and aromatic amines.

  14. Dynamic Kinetic Resolution of 2-Phenylpropanal Derivatives to Yield β-Chiral Primary Amines via Bioamination

    NARCIS (Netherlands)

    Fuchs, C.S.; Hollauf, M.; Meissner, M.; Simon, R.C.; Besset, T.; Reek, J.N.H.; Riethorst, W.; Zepeck, F.; Kroutil, W.

    2014-01-01

    The amination of racemic alpha-chiral aldehydes, 2-phenylpropanal derivatives, was investigated employing omega-transaminases. By medium and substrate engineering the optical purity of the resulting β-chiral chiral amine could be enhanced to reach optical purities up to 99% ee. Using enantiocompleme

  15. Occurrence of biogenic amines in Miso, Japanese traditional fermented soybean paste.

    Science.gov (United States)

    Byun, Bo Young; Mah, Jae-Hyung

    2012-12-01

    The objective of this study was to analyze overall contents of biogenic amines in Miso and thereby evaluate the safety of the food. Through HPLC analysis of 22 different Miso products, it was found that most samples had low biogenic amine contents. However, some samples contained both histamine and tyramine close to hazardous levels of the amines, which indicate that the amounts of biogenic amines in Miso are not completely within the safe level for human health. Meanwhile, the biogenic amine contents showed no clear relationship with physicochemical parameters, whereas they revealed a good relationship with the ratio of soybean to other grains used in raw material. Thus, it turned out that biogenic amine contents in Miso are primarily affected by the ratio of raw ingredients, especially soybeans. The aerobic plate counts of Miso samples ranged from 3 to 8 Log CFU/g, and all the strains isolated from Miso samples were found to produce biogenic amines. Most strains were identified to be Bacillus subtilis, often regarded as the predominant contaminant bacteria in Miso, and highly capable of producing tyramine and spermine. Taken together, therefore, this study suggests that variability of biogenic amine contents in Miso are primarily attributed to the ratio of raw ingredients in the food that affects the relative contribution level of bacterial contaminants to the contents.

  16. Development of low-cost amine-enriched solid sorbent for CO2 capture.

    Science.gov (United States)

    Bachelor, Thuy Thi Nguyen; Toochinda, Pisanu

    2012-12-01

    CO2 capture amine-enriched solid sorbent using agricultural wastes, such as bagasse, or industrial wastes, such as mullite, as support materials could provide efficient alternative CO2 reduction due to their low cost and ability to shape into many forms. These amine-enriched solid sorbents were prepared by treatment with monoethanolamine (MEA), diethanolamine, piperazine (PZ), 2-(2-aminoethyl-amino) ethanol (AEEA) and mixtures of these amines. The performance of amine-enriched solid sorbents with various amine compositions was studied in a tubular column at 1 atm and an adsorption temperature of 303 K. The CO2 capture capacities of the amine-enriched solid sorbents were determined by gas chromatography at a desorption temperature of 393 K. Amine-enriched solid sorbents in this study exhibited high performance CO2 capture. The MEA-PZ-enriched solid sorbent does have the highest CO2 capture performance of the amine-enriched bagasse support-based sorbents, and the results indicate that PZ is the most effective promoter in this study. The CO2 capture performances of solid sorbents in this study were compared with commercial solid sorbents. This study could lead to the development of low-cost solid sorbents for CO2 capture that can be used in many industrial applications.

  17. Continuous CO2 capture in a circulating fluidized bed using supported amine sorbents

    NARCIS (Netherlands)

    Veneman, R.; Li, Z.; Hogendoorn, J.A.; Kersten, S.R.A.; Brilman, D.W.F.

    2012-01-01

    In this work, supported amine sorbents were prepared by physical impregnation of silica and polymethylmethacrylate (PMMA) with tetraethylenepentamine (TEPA) and studied for post-combustion CO2 capture purposes in a lab scale circulating fluidized bed (CFB) reactor. Sorbent amine loading and support

  18. Post-Combustion CO2 capture using supported amine sorbents: A process integration study

    NARCIS (Netherlands)

    Veneman, R.; Kamphuis, H.; Brilman, D.W.F.

    2013-01-01

    We have evaluated the feasibility of supported amine sorbents (SAS) for their application in post- combustion CO2 capture. For this, the energy efficiency of a power plant equipped with a supported amine based capture facility is compared with the energy efficiency of a power plant equipped with a s

  19. 40 CFR 721.9620 - Aromatic sulfonic acid compound with amine.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Aromatic sulfonic acid compound with... Specific Chemical Substances § 721.9620 Aromatic sulfonic acid compound with amine. (a) Chemical substance... aromatic sulfonic acid compound with amine (PMN P-93-832) is subject to reporting under this section...

  20. Magnetic Resonance Determinations of Structure and Reaction Kinetics of Epoxy/Amine Systems.

    Science.gov (United States)

    1981-12-31

    bisphenol A ( DGEBA ), and two model compounds, a secondary amine nitroxide and a tertiary amine nitroxide. The rate constants for both reactions (kl, k2...EPR EXPERIMENTS ON EPOXY RESINS ....................................... 4 2.1 Nitroxide- DGEBA Kinetics ......................................... 4 2.2...dependence of the rate constants for METAMIN and DIMETAMIN reactions with DGEBA ...................................... 14 11. EPR spectra observed at 299

  1. 21 CFR 173.70 - Chloromethylated aminated styrene-divinylbenzene resin.

    Science.gov (United States)

    2010-04-01

    ... resin. 173.70 Section 173.70 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Chloromethylated aminated styrene-divinylbenzene resin. Chloromethylated aminated styrene-divinylbenzene copolymer... resin dispersion. (c) The additive is used as a decolorizing and clarification agent for treatment...

  2. Benzoyl peroxide (BPO)-promoted oxidative trifluoromethylation of tertiary amines with trimethyl(trifluoromethyl)silane.

    Science.gov (United States)

    Chu, Lingling; Qing, Feng-Ling

    2010-09-14

    The benzoyl peroxide (BPO)-promoted oxidative functionalization of tertiary amines under transition-metal-free reaction conditions was developed. Various 1-trifluoromethylated tetrahydroisoquinoline derivatives were prepared by employing this method. It constitutes the first example of direct trifluoromethylation of tertiary amines.

  3. Palladium-catalyzed Substitution of Ketone or Aldehyde Bearing Aryl Triflates by Amines or Amides

    Institute of Scientific and Technical Information of China (English)

    TAO Xiaochun; DAI Chunya; CAO Xiongjie; CAI Lisheng; PIKE Victor W

    2009-01-01

    Various aryl triflates, bearing ketone or aldehyde groups, were evaluated for palladium-mediated introduction of an amino group at the triflate position in the presence of various phosphine ligands. BINAP was best for secondary amines, MOP-type ligand for primary or small secondary amines and Xantphos for primary or cyclic secondary amides. No ligand was found effective for acyclic secondary amides.

  4. 40 CFR 721.7770 - Alkylphenoxypoly(oxyethylene) sulfuric acid ester, substituted amine salt.

    Science.gov (United States)

    2010-07-01

    ... acid ester, substituted amine salt. 721.7770 Section 721.7770 Protection of Environment ENVIRONMENTAL... ester, substituted amine salt. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as alkyl phenoxypoly(oxyethylene) sulfuric acid ester,...

  5. Extension of the cubic-plus-association (CPA) equation of state to amines

    DEFF Research Database (Denmark)

    Kaarsholm, Mads Kristian; Derawi, Samer; Michelsen, Michael Locht

    2005-01-01

    The cubic-plus-association (CPA) equation of state has been extended to modeling mixtures containing amines. Special focus was given to primary and secondary amines, which are known to self-associate, thus forming hydrogen bonds in mixtures with alkanes. Pure-compound parameters have been...

  6. INTERACTIONS BETWEEN KETONES AND AMINES IN PHOTOINITIATING SYSTEMS USED FOR RADICAL POLYMERIZATION

    Institute of Scientific and Technical Information of China (English)

    WU Shikang; FOUASSIER ,J. P.

    1990-01-01

    Time resolved laser spectroscopy and GC/MS were used to investigate the primary processes and the side reactions occurring in benzophenone and chlorothioxanthone/amine systems used as photoinitiators of radical polymerization. The discrepancy observed between the experimental data and the expected behaviour is accounted for by detrimental chemicalreaction involving the ketone triplet state, the ketyl radical and the amine - derived radical.

  7. Tris{4-[(1,3-diphenyl-1H-pyrazol-4-ylmethylene]-41-aminobiphenyl}amine

    Directory of Open Access Journals (Sweden)

    Sandhya P. Veettil

    2010-04-01

    Full Text Available Tris{4-[(1,3-diphenyl-1H-pyrazol-4-ylmethylene]-41-aminobiphenyl}amine was synthesized from N-(4-bromophenyl-N-[(1,3-diphenyl-1H-pyrazol-4-ylmethylene]amine and tris(4-bromophenylamine based on Ullmann coupling reaction. The synthesized compound was characterized by NMR, IR, MS and elemental analysis.

  8. Concentration of Biogenic Amines in ‘Pinot Noir’ Wines Produced in Croatia

    Directory of Open Access Journals (Sweden)

    Ana Jeromel

    2012-03-01

    Full Text Available The origins of biogenic amines are sound grapes, alcoholic fermentations, malolactic fermentation and microbial activities during wine storage. These biologically produced amines are essential at low concentrations for optimal metabolic and physiological functions in animals, plants and micro-organisms. During alcoholic fermentation the degree of maceration is the first factor that affects the extraction of compounds present in the grape skin, among them aminoacids, precursors of biogenic amines. The aim of the present work was to study the changes of the concentration of biogenic amines in wines made from Vitis vinifera ‘Pinot noir’ from Plešivica (vintage 2009 produced with classical maceration, cold maceration and use of sur lie method. Biogenic amines were quantified using a reversed-phase high performance liquid chromatography (HPLC with fluorescence detection after pre-column derivatization with o-phthalaldehyde (OPA. In ‘Pinot noir’ wines tested, histamine was the most abundant biogenic amine followed by tryptamine and 2-Phenylethylamine. Total amount of biogenic amines ranged from 8.72 mg/L in wines made with classical maceration up to 9.34 mg/L in sur lie wines. In summary, from the results obtained in this study, it can be concluded that sur lie technology can influence the formation of biogenic acids since the release of amino acids is probably more pronounced in wines aged with lees and stirred weekly. No significant differences were found in the concentration of biogenic amines in relation to the used maceration process.

  9. Enhanced reactivities toward amines by introducing an imine arm to the pincer ligand: Direct coupling of two amines to form an imine without oxidant

    KAUST Repository

    He, Lipeng

    2012-07-23

    Dehydrogenative homocoupling of primary alcohols to form esters and coupling of amines to form imines was accomplished using a class of novel pincer ruthenium complexes. The reactivities of the ruthenium pincer complexes for the direct coupling of amines to form imines were enhanced by introducing an imine arm to the pincer ligand. Selective oxidation of benzylamines to imines was achieved using aniline derivatives as the substrate and solvent. © 2012 American Chemical Society.

  10. Amine functionalized cubic mesoporous silica nanoparticles as an oral delivery system for curcumin bioavailability enhancement

    Science.gov (United States)

    Budi Hartono, Sandy; Hadisoewignyo, Lannie; Yang, Yanan; Meka, Anand Kumar; Antaresti; Yu, Chengzhong

    2016-12-01

    In the present work, a simple method was used to develop composite curcumin-amine functionalized mesoporous silica nanoparticles (MSN). The nanoparticles were used to improve the bioavailability of curcumin in mice through oral administration. We investigated the effect of particle size on the release profile, solubility and oral bioavailability of curcumin in mice, including amine functionalized mesoporous silica micron-sized-particles (MSM) and MSN (100-200 nm). Curcumin loaded within amine functionalized MSN (MSN-A-Cur) had a better release profile and a higher solubility compared to amine MSM (MSM-A-Cur). The bioavailability of MSN-A-Cur and MSM-A-Cur was considerably higher than that of ‘free curcumin’. These results indicate promising features of amine functionalized MSN as a carrier to deliver low solubility drugs with improved bioavailability via the oral route.

  11. In Situ Preparation of Polyether Amine Functionalized MWCNT Nanofiller as Reinforcing Agents

    Directory of Open Access Journals (Sweden)

    Ayber Yıldrım

    2014-01-01

    Full Text Available In situ preparation of polyether amine functionalized cross-linked multiwalled carbon nanotube (MWCNT nanofillers may improve the thermal and mechanical properties of the composites in which they are used as reinforcing agents. The reduction and functionalization of MWCNT using ethylenediamine in the presence of polyether amine produced stitched MWCNT's due to the presence of two amine (–NH2 functionalities on both sides of the polymer. Polyether amine was chosen to polymerize the carboxylated MWCNT due to its potential to form bonds with the amino groups and carboxyl groups of MWCNT which produces a resin used as polymeric matrix for nanocomposite materials. The attachment of the polyether amine (Jeffamine groups was verified by TGA, FT-IR, XRD, SEM, and Raman spectroscopy. The temperature at which the curing enthalpy is maximum, observed by DSC, was shifted to higher values by adding functionalized MWCNT. SEM images show the polymer formation between MWCNT sheets.

  12. Biogenic Amines as Quality Marker in Organic and Fair-Trade Cocoa-Based Products

    Directory of Open Access Journals (Sweden)

    Donatella Restuccia

    2016-08-01

    Full Text Available In this study, the quantitative determination of eight biogenic amines (cadaverine, serotonin, histamine, spermidine, spermine, tyramine, putrescine and β-phenylethylamine by an liquid chromatography method with evaporative light scattering detection was performed. The analysis of several samples of conventional, organic and fair trade cocoa-derivatives showed that organic and fair trade samples always contain much lower amine concentrations in comparison with their conventional counterparts, supporting the idea that biogenic amines can be regarded as cocoa quality markers. Irrespective of the kind of sample, results also showed that the most abundant amines were histamine, tyramine, spermidine, putrescine and spermine while β-phenylethylamine, cadaverine and serotonine have been found more rarely, all the amines never reaching dangerous amounts for consumer health. With the aim to confirm the experimental results, clustering analysis was performed on samples and instrumental results using principal component analysis.

  13. Effect of autochthonous starter cultures on the biogenic amine content of ewe's milk cheese throughout ripening.

    Science.gov (United States)

    Renes, E; Diezhandino, I; Fernández, D; Ferrazza, R E; Tornadijo, M E; Fresno, J M

    2014-12-01

    Cheese is among the most commonly implicated foods associated with biogenic amines poisoning. The aim of this study was to evaluate the effects of the type of autochthonous starter culture and ripening time on the concentration of biogenic amines (histamine, tyramine, putrescine, cadaverine, tryptamine, β-phenylethylamine, spermine and spermidine) in cheeses made from pasteurized ewe's milk. 4 cheese batches were made, in duplicate, and ripened for 7 months. The biogenic amines of 40 cheeses were analysed by high performance liquid chromatography. The predominant biogenic amines determined at the end of the ripening time were phenylethylamine, spermine and tryptamine. Together, these accounted for 81% of the total of biogenic amines studied. The type of starter culture used to make the ewe's cheese had a significant effect (p culture made up entirely of Lactococcus lactis subsp. lactis and L. lactis subsp. cremoris or of the same in combination with Lactobacillus plantarum.

  14. Optimization of selection of chain amine scrubbers for CO2 capture.

    Science.gov (United States)

    Al-Marri, Mohammed J; Khader, Mahmoud M; Giannelis, Emmanuel P; Shibl, Mohamed F

    2014-12-01

    In order to optimize the selection of a suitable amine molecule for CO2 scrubbers, a series of ab initio calculations were performed at the B3LYP/6-31+G(d,p) level of theory. Diethylenetriamine was used as a simple chain amine. Methyl and hydroxyl groups served as examples of electron donors, and electron withdrawing groups like trifluoromethyl and nitro substituents were also evaluated. Interaction distances and binding energies were employed as comparison operators. Moreover, natural bond orbital (NBO) analysis, namely the second order perturbation approach, was applied to determine whether the amine-CO2 interaction is chemical or physical. Different sizes of substituents affect the capture ability of diethylenetriamine. For instance, trifluoromethyl shields the nitrogen atom to which it attaches from the interaction with CO2. The results presented here provide a means of optimizing the choice of amine molecules for developing new amine scrubbers.

  15. Alteration of the Donor/Acceptor Spectrum of the (S-Amine Transaminase from Vibrio fluvialis

    Directory of Open Access Journals (Sweden)

    Maika Genz

    2015-11-01

    Full Text Available To alter the amine donor/acceptor spectrum of an (S-selective amine transaminase (ATA, a library based on the Vibrio fluvialis ATA targeting four residues close to the active site (L56, W57, R415 and L417 was created. A 3DM-derived alignment comprising fold class I pyridoxal-5′-phosphate (PLP-dependent enzymes allowed identification of positions, which were assumed to determine substrate specificity. These positions were targeted for mutagenesis with a focused alphabet of hydrophobic amino acids to convert an amine:α-keto acid transferase into an amine:aldehyde transferase. Screening of 1200 variants revealed three hits, which showed a shifted amine donor/acceptor spectrum towards aliphatic aldehydes (mainly pentanal, as well as an altered pH profile. Interestingly, all three hits, although found independently, contained the same mutation R415L and additional W57F and L417V substitutions.

  16. Amine synthesis via iron-catalysed reductive coupling of nitroarenes with alkyl halides

    Science.gov (United States)

    Cheung, Chi Wai; Hu, Xile

    2016-08-01

    (Hetero)Aryl amines, an important class of organic molecules in medicinal chemistry, are most commonly synthesized from anilines, which are in turn synthesized by hydrogenation of nitroarenes. Amine synthesis directly from nitroarenes is attractive due to improved step economy and functional group compatibility. Despite these potential advantages, there is yet no general method for the synthesis of (hetero)aryl amines by carbon-nitrogen cross-coupling of nitroarenes. Here we report the reductive coupling of nitroarenes with alkyl halides to yield (hetero)aryl amines. A simple iron catalyst enables the coupling with numerous primary, secondary and tertiary alkyl halides. Broad scope and high functional group tolerance are demonstrated. Mechanistic study suggests that nitrosoarenes and alkyl radicals are involved as intermediates. This new C-N coupling method provides general and step-economical access to aryl amines.

  17. Commercially Supplied Amine-Modified siRNAs May Require Ultrafiltration prior to Conjugation with Amine-Reactive Compounds

    Directory of Open Access Journals (Sweden)

    Shannen Lau

    2011-01-01

    Full Text Available Conjugation of siRNA to macromolecules such as serum albumin has multiple potential benefits, including enhanced extravasation via albumin-mediated transcytosis across endothelial cells and reduced renal clearance. In attempting to conjugate siRNA to albumin, we used commercially sourced amine-modified siRNA and reacted it with the heterobifunctional linker succinimidyl 4-[N-maleimidomethyl]cyclohexane-1-carboxylate (SMCC to introduce a maleimide group suitable for conjugation to the thiol group of the surface-exposed cysteine residue (Cys 34 within albumin. We found the conjugation of the SMCC-treated siRNA to bovine serum albumin (BSA to be very inefficient and investigated the cause of the low yield of conjugate. Ultrafiltration with phosphate-buffered saline prior to activation with SMCC dramatically increased the yield of siRNA-albumin conjugate (~15-fold. Communication with the commercial supplier revealed that ammonium acetate buffer was used in a desalting step as part of the siRNA purification process prior to supply, likely resulting in ammonium counterions to the siRNA polyanion, which would interfere with conjugation by consuming the SMCC. After ultrafiltration, a greatly reduced amount of SMCC could be used to affect conjugation, without significant reduction in yield. These data indicate that amine-modified siRNA sourced commercially may require ultrafiltration or dialysis prior to use in conjugation reactions.

  18. Influence of amine structural characteristics on N-nitrosamine formation potential relevant to postcombustion CO2 capture systems.

    Science.gov (United States)

    Dai, Ning; Mitch, William A

    2013-11-19

    Concerns have arisen for the possible contamination of air or drinking water supplies downwind of amine-based CO2 capture facilities by potentially carcinogenic N-nitrosamines formed from reactions between flue gas NOx and amine solvents. This study evaluated the influence of amine structure on the potential to form total N-nitrosamines within the absorber and washwater units of a laboratory-scale CO2 capture reactor, and in the solvent after a pressure-cooker treatment as a mimic of desorber conditions. Among 16 amines representing 3 amine classes (alkanolamines, straight-chain and cyclic diamines, and amino acids), the order of the amine was the primary determinant of total N-nitrosamine formation in the absorber unit, with total N-nitrosamine formation in the order: secondary amines ≈ tertiary amines ≫ primary amines. Similar results were observed upon pressure-cooker treatment, due to reactions between nitrite and amines at high temperature. For secondary and tertiary amines, total N-nitrosamine formation under these desorber-like conditions appeared to be more important than in the absorber, but for primary amines, significant formation of total N-nitrosamines was only observed in the absorber. For diamines and amino acids, total N-nitrosamine accumulation rates in washwaters were lowest for primary amines. For alkanolamines, however, total N-nitrosamine accumulation in the washwater was similar regardless of alkanolamine order, due to the combined effects of amine reactivity toward nitrosation and amine volatility. While total N-nitrosamine accumulation rates in washwaters were generally 1-2 orders of magnitude lower than in the absorber, they were comparable to absorber rates for several primary amines. Decarboxylation of the amino acid sarcosine resulted in the accumulation of significant concentrations of N-nitrosodimethylamine and N-nitrodimethylamine in the washwater.

  19. Effect of foamability index of short chain alkyl amines on flotation of quartz

    Directory of Open Access Journals (Sweden)

    Szczerkowska Sabina

    2016-01-01

    Full Text Available Amines can be used for flotation of various minerals, especially quartz. The flotation efficiency of quartz depends on the amine type and dose. It was proved that the shorter alkyl amine, higher amine concentration has to be used to recover quartz at the same level. In flotation amines play a role of both collectors and frothers. The ability of a amine to collect particles can be expressed in the form of contact angle, while the foaming properties by different parameters including dynamic foamability index (DFI and critical coalescence concentration (CCC. Determination of DFI and CCC requires advanced techniques and methods. Therefore, in this paper a rapid and facile method for determination of foaming properties of amines and also other surfactants was used. It was based on measuring the initial foam and froth heights in a conventional flotation machine at different concentrations of surfactants. The foam height-concentration curve was described by utilizing an empirical equation which was based on one-adjustable parameter called the foamability index (FI. In this work the foamability index was determined for butylamine (ButNH2, hexylamine (HexNH2 and octylamine (OctNH2 as examples of short chain alkyl amines. The determined foamability indices were 92, 12 and 4 mg/dm3 for ButNH2, HexNH2 and OctNH2, respectively. It was shown that when the flotation results of quartz were presented in the form of recovery versus normalized amine concentration in relation to the foamability index (c/FI, all the experimental data points converged to one curve. It indicates that amines act similarly but at different concentrations expressed as FI. The foamability index seems to be a useful parameter for characterizing any flotation frother.

  20. 40 CFR 721.3830 - Formaldehyde, reaction products with an alkylated phenol and an aliphatic amine (generic).

    Science.gov (United States)

    2010-07-01

    ... an alkylated phenol and an aliphatic amine (generic). 721.3830 Section 721.3830 Protection of... products with an alkylated phenol and an aliphatic amine (generic). (a) Chemical substance and significant..., reaction products with an alkylated phenol and an aliphatic amine (PMN P-99-0531) is subject to...

  1. Reductive amination of aldehydes and ketones using sodium borohydride in the presence of silica chloride under solvent-free conditions

    Institute of Scientific and Technical Information of China (English)

    Heshmatollah; Alinezhad; Mahmood; Tajbakhsh; Neda; Hamidi

    2010-01-01

    A simple and convenient procedure for the preparation of amines from aldehydes and ketones with sodium borohydride activated by silica chloride as a catalyst under solvent-free conditions is described.A variety of aliphatic and aromatic aldehydes,ketones and amines when mixed with NaBH_4/silica chloride at room temperature,afforded excellent yield of the corresponding amines.

  2. Targeting bacteria via iminoboronate chemistry of amine-presenting lipids.

    Science.gov (United States)

    Bandyopadhyay, Anupam; McCarthy, Kelly A; Kelly, Michael A; Gao, Jianmin

    2015-03-12

    Synthetic molecules that target specific lipids serve as powerful tools for understanding membrane biology and may also enable new applications in biotechnology and medicine. For example, selective recognition of bacterial lipids may give rise to novel antibiotics, as well as diagnostic methods for bacterial infection. Currently known lipid-binding molecules primarily rely on noncovalent interactions to achieve lipid selectivity. Here we show that targeted recognition of lipids can be realized by selectively modifying the lipid of interest via covalent bond formation. Specifically, we report an unnatural amino acid that preferentially labels amine-presenting lipids via iminoboronate formation under physiological conditions. By targeting phosphatidylethanolamine and lysylphosphatidylglycerol, the two lipids enriched on bacterial cell surfaces, the iminoboronate chemistry allows potent labelling of Gram-positive bacteria even in the presence of 10% serum, while bypassing mammalian cells and Gram-negative bacteria. The covalent strategy for lipid recognition should be extendable to other important membrane lipids.

  3. Propylene Polymerization Catalysts with Sulfonyl Amines as Internal Electron Donors

    Institute of Scientific and Technical Information of China (English)

    Wang Liang; Yin Baozuo; Yi Jianjun; Cui Chunming

    2013-01-01

    Three sulfonyl aliphatic amines [(R2SO2)2NR1, viz.:compound 1, in which R1=Me, and R2=Ph;compound 2, in which R1=n-Bu, and R2=CF3;and compound 3, in which R1=C8H17, and R2=CF3], have been synthesized and employed as internal electron donors (IED) for the preparation of Ziegler-Natta catalysts for the polymerization of propylene. The contents of Ti, H and C in these catalysts have been determined by elemental analysis and UV-vis spectrophotometry. The effect of the structure and dosage of the electron donor, the Al/Ti ratio and the polymerization temperature on the catalyst performance has been studied. Under optimized conditions, the catalyst with a highest activity yielded polypropylene with high isotacticity in the absence of external electron donors.

  4. Highly Aminated Mesoporous Silica Nanoparticles with Cubic Pore Structure

    KAUST Repository

    Suteewong, Teeraporn

    2011-01-19

    Mesoporous silica with cubic symmetry has attracted interest from researchers for some time. Here, we present the room temperature synthesis of mesoporous silica nanoparticles possessing cubic Pm3n symmetry with very high molar ratios (>50%) of 3-aminopropyl triethoxysilane. The synthesis is robust allowing, for example, co-condensation of organic dyes without loss of structure. By means of pore expander molecules, the pore size can be enlarged from 2.7 to 5 nm, while particle size decreases. Adding pore expander and co-condensing fluorescent dyes in the same synthesis reduces average particle size further down to 100 nm. After PEGylation, such fluorescent aminated mesoporous silica nanoparticles are spontaneously taken up by cells as demonstrated by fluorescence microscopy.

  5. Aerobic Linear Allylic C-H Amination: Overcoming Benzoquinone Inhibition.

    Science.gov (United States)

    Pattillo, Christopher C; Strambeanu, Iulia I; Calleja, Pilar; Vermeulen, Nicolaas A; Mizuno, Tomokazu; White, M Christina

    2016-02-03

    An efficient aerobic linear allylic C-H amination reaction is reported under palladium(II)/bis-sulfoxide/Brønsted base catalysis. The reaction operates under preparative, operationally simple conditions (1 equiv of olefin, 1 atm O2 or air) with reduced Pd(II)/bis-sulfoxide catalyst loadings while providing higher turnovers and product yields than systems employing stoichiometric benzoquinone (BQ) as the terminal oxidant. Pd(II)/BQ π-acidic interactions have been invoked in various catalytic processes and are often considered beneficial in promoting reductive functionalizations. When such electrophilic activation for functionalization is not needed, however, BQ at high concentrations may compete with crucial ligand (bis-sulfoxide) binding and inhibit catalysis. Kinetic studies reveal an inverse relationship between the reaction rate and the concentration of BQ, suggesting that BQ is acting as a ligand for Pd(II) which results in an inhibitory effect on catalysis.

  6. Thermodynamics of organic mixtures containing amines. VIII. Systems with quinoline

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, Juan Antonio [G.E.T.E.F., Grupo Especializado en Termodinamica de Equilibrio entre Fases, Departamento de Fisica Aplicada, Facultad de Ciencias, Universidad de Valladolid, E-47071 Valladolid (Spain)], E-mail: jagl@termo.uva.es; Domanska, Urszula; Zawadzki, Maciej [Physical Chemistry Division, Faculty of Chemistry, Warsaw University of Technology, 00-664 Warsaw (Poland)

    2008-08-15

    (Solid + liquid) equilibrium temperatures for mixtures containing quinoline and 1-dodecanol, 1-hexadecanol, or 1-octadecanol have been measured using a dynamic method. (Quinoline + benzene, +alkane, or +1-alkanol) systems were investigated using DISQUAC. The corresponding interaction parameters are reported. The model yields a good representation of molar excess Gibbs free energies, G{sup E}, molar excess enthalpies, H{sup E}, and of the (solid + liquid) equilibria, SLE. Interactional and structural effects were analysed comparing H{sup E} and the molar excess internal energy at constant volume, U{sub V}{sup E}. It was encountered that structural effects are very important in systems involving alkanes or 1-alkanols. Interactions between amine molecules are stronger in mixtures with quinoline than in those containing pyridine, which was ascribed to the higher polarizability of quinoline.

  7. Trace amine-associated receptor 1-Family archetype or iconoclast?

    Science.gov (United States)

    Grandy, David K

    2007-12-01

    Interest has recently been rekindled in receptors that are activated by low molecular weight, noncatecholic, biogenic amines that are typically found as trace constituents of various vertebrate and invertebrate tissues and fluids. The timing of this resurgent focus on receptors activated by the "trace amines" (TA) beta-phenylethylamine (PEA), tyramine (TYR), octopamine (OCT), synephrine (SYN), and tryptamine (TRYP) is the direct result of 2 publications that appeared in 2001 describing the cloning of a novel G protein-coupled receptor (GPCR) referred to by their discoverers Borowsky et al. as TA1 and Bunzow et al. as TA receptor 1 (TAR1). When heterologously expressed in Xenopus laevis oocytes and various eukaryotic cell lines, recombinant rodent and human TAR dose-dependently couple to the stimulation of adenosine 3',5'-monophosphate (cAMP) production. Structure-activity profiling based on this functional response has revealed that in addition to the TA, other biologically active compounds containing a 2-carbon aliphatic side chain linking an amino group to at least 1 benzene ring are potent and efficacious TA receptor agonists with amphetamine (AMPH), methamphetamine, 3-iodothyronamine, thyronamine, and dopamine (DA) among the most notable. Almost 100 years after the search for TAR began, numerous TA1/TAR1-related sequences, now called TA-associated receptors (TAAR), have been identified in the genome of every species of vertebrate examined to date. Consequently, even though heterologously expressed TAAR1 fits the pharmacological criteria established for a bona fide TAR, a major challenge for those working in the field is to discern the in vivo pharmacology and physiology of each purported member of this extended family of GPCR. Only then will it be possible to establish whether TAAR1 is the family archetype or an iconoclast.

  8. Bioactive amines in sorghum: method optimisation and influence of line, tannin and hydric stress.

    Science.gov (United States)

    Paiva, Caroline Liboreiro; Evangelista, Warlley Pinheiro; Queiroz, Valéria Aparecida Vieira; Glória, Maria Beatriz Abreu

    2015-04-15

    The profile and levels of bioactive amines in different sorghum lines were reported for the first time. The amines were quantified by ion-pair HPLC, post-column derivatisation with o-phthalaldehyde and fluorimetric detection. The extraction procedure was optimised: 420 μm particle size, extraction with 5% trichloroacetic acid and three extractions. The screening of 22 sorghum lines showed that four of the ten amines investigated were detected. Spermine and spermidine were the prevalent amines (100%), followed by putrescine (77%) and cadaverine (14%). Total amines ranged from 5.8 to 41.4 mg/100 g, and the polyamines represented 60-100% of the total. Sorghum without tannin had higher amines levels compared to sorghum with tannin and cadaverine was specific to samples without tannin. Hydric stress caused accumulation of spermidine in the grains and affected the levels of other amines at rates depending on the presence or not of tannin. Sorghum is a significant source of polyamines.

  9. Visible Light Induced Green Transformation of Primary Amines to Imines Using a Silicate Supported Anatase Photocatalyst

    Directory of Open Access Journals (Sweden)

    Sifani Zavahir

    2015-01-01

    Full Text Available Catalytic oxidation of amine to imine is of intense present interest since imines are important intermediates for the synthesis of fine chemicals, pharmaceuticals, and agricultural chemicals. However, considerable efforts have been made to develop efficient methods for the oxidation of secondary amines to imines, while little attention has until recently been given to the oxidation of primary amines, presumably owing to the high reactivity of generated imines of primary amines that are easily dehydrogenated to nitriles. Herein, we report the oxidative coupling of a series of primary benzylic amines into corresponding imines with dioxygen as the benign oxidant over composite catalysts of TiO2 (anatase-silicate under visible light irradiation of λ > 460 nm. Visible light response of this system is believed to be as a result of high population of defects and contacts between silicate and anatase crystals in the composite and the strong interaction between benzylic amine and the catalyst. It is found that tuning the intensity and wavelength of the light irradiation and the reaction temperature can remarkably enhance the reaction activity. Water can also act as a green medium for the reaction with an excellent selectivity. This report contributes to the use of readily synthesized, environmentally benign, TiO2 based composite photocatalyst and solar energy to realize the transformation of primary amines to imine compounds.

  10. Basic biogenic aerosol precursors: Agricultural source attribution of volatile amines revised

    Science.gov (United States)

    Kuhn, U.; Sintermann, J.; Spirig, C.; Jocher, M.; Ammann, C.; Neftel, A.

    2011-08-01

    Despite recent evidence on an important role of volatile amines in the nucleation of particulate matter, very scarce information is available on their atmospheric abundance and source distribution. Previous measurements in animal housings had identified livestock husbandry as the main amine source, with trimethylamine (TMA) being the key component. This has led to the assumption that the agricultural sources for amines are similar as for ammonia, emitted throughout the cascade of animal excretion, storage and application in the field. In this study, we present the first micrometeorological flux measurements as well as dynamic enclosure experiments showing that the amine source strength from stored slurry is negligible, implying significant consequences for the global amine emission inventory. In the case of cattle, amine production is attributed to the animal's rumination activity and exhalation is suggested to be an important emission pathway, similar to the greenhouse gas methane. Fodder like hay and silage also emits volatile amines, potentially assigning these alkaloid compounds a key function in enhancing particle formation in remote areas.

  11. Selective spectrophotometric determination of some primary amines using 2,4-dinitrofluorobenzene reagent

    Directory of Open Access Journals (Sweden)

    Theia’a N. Al-Sabha

    2015-07-01

    Full Text Available A spectrophotometric method is developed for the quantitative determination of some primary aliphatic and aromatic amines, i.e., allyl amine, 1,5-diaminopentane, 1,6-diaminohexane, cyclohexylamine, m-aminophenol, benzidine and p-phenylenediamine. The method is based on the interaction between these amines and 2,4-dinitrofluorobenzene (DNFB reagent. The spectra of the products show maximum absorption that ranged from 355–357 nm and 366–377 nm with molar absorptivities that ranged from 1.086 × 104–6.398 × 104 and 7.566 × 103–1.581 × 104 l/mol cm for aliphatic and aromatic primary amines, respectively. Beer’s law is obeyed in the concentration range of 0.25–8.0, 1.0–10, 0.25–2.50, 1.0–8.0, 2.0–20, 1.0–12.0 and 1.0–10.0 μg/ml for the above mentioned amines, respectively, and the mean percent recoveries ranged between 97.8% and 103.3% with precision (RSD better than 5.5% for all the amines under study. In addition, the stability constant has been determined and the mechanism is proposed for the DNFB-amine products.

  12. Internal conversion mediated by specific nuclear motions: The nitrogen inversion in amines

    Energy Technology Data Exchange (ETDEWEB)

    Klein, Liv B.; Sølling, Theis I., E-mail: theis@kiku.dk

    2014-10-17

    Graphical abstract: - Highlights: • Primary and secondary amines show different photophysical behavior to tertiary. • Deuteration in amines significantly increases decay time of parent ions. • The planarization motion is important for the rate of internal conversion. • The internal conversion in amines is a non-ergodic process. - Abstract: To investigate the influence of amine structure on the internal conversion from S{sub 2} to S{sub 1}, three aliphatic amines containing the same number of degrees of freedom, but with different degree of N-substitution, were investigated with femtosecond time-resolved mass spectrometry. As N-substituents lower the excitation energies, and the excitation in all cases is by a 200 nm photon, the S{sub 1} density-of-states in the Franck–Condon region will be high for the more N-alkylated amine. This, according to standard models, should lead to faster internal conversion. The experimental results are in contrast to this, indicating non-ergodic behavior and a coupling of the states by very few molecular vibrations. This was further investigated by substituting differing numbers of hydrogen atoms with deuterium in two amines, one primary and one tertiary, thus freezing the degrees of freedom while altering the N-substituent mass. In both case, deuteration resulted in a significantly longer lifetime of the initially excited state, confirming the importance of the N-inversion motion in the description of the dynamics of internal conversion.

  13. [Present aspects and problems regarding occupational bladder cancer due to exposure to aromatic amines].

    Science.gov (United States)

    Yamamura, J

    1989-12-01

    About a century has passed since the first case of bladder cancer due to occupational exposure to carcinogenic aromatic amines was reported. In the major developed countries of the world, it is forbidden to manufacture and/or to use such aromatic amines. In Japan in the 1950's, many workers were exposed to carcinogenic aromatic amines, but in 1972, the Labor Safety and Health Act came into force and manufacturing and/or using of four kinds of aromatic amines were forbidden. Recently it has been reported that the risk of bladder cancer in workers exposed to aromatic amines before the ban of these chemicals is approximately from several times to a hundred times compared with the general population, and some reports say that dose-response relationship was observed. The important issues now are the carcinogenicity of other kinds of aromatic amines besides benzidine and 2-naphthylamine, carcinogenicity of metabolites of several substances like synthetic dyes, and carcinogenic aromatic amines as impurities in substances imported from developing countries. The type of exposure to these carcinogens changes low level and long period exposures. In addition to the chemical or dye industries, an increased risk of bladder cancer was observed among workers handling leather and rubber and those engaged in printing, textile industries, hairdressing, truck driving and so on. In the future, it will be necessary to cooperate with the departments of epidemiology, toxicology and clinical medicine for the purpose of estimating the risk of these occupations and the health care administration of the exposed workers.

  14. Blending Behavior of Polysulfone, Polyvinyl Acetate and Amines in Dimethyl Acetamide Solvent

    Directory of Open Access Journals (Sweden)

    Asim Mushtaq

    2014-02-01

    Full Text Available In this study, research will be carried out to classify the blending behavior of glassy and rubbery polymer in solvent with amines. Commercially preface of a polymer prepared from a new monomer is uncertain and enormously expensive. A strategy to introduce new products into the market without a large investment is to take dissimilar polymers, amines and blend them together to make a new product with unique properties. The blending of polyvinyl acetate, polysulfone and diethanol amine, methyl diethanol amine, mono ethanol amine are examined with dimethyl acetamide solvent, which gives the results of appearance, pH and viscosity values by using measuring device viscometer and general pH testing technique. Through getting these results, the intrinsic miscibility of the mixture was finally established which shows that the homogenous or heterogeneous blends are depending on the blend preparation method and percentage of polymers and amines. The achievement of this advance has been restricted, because the mechanical properties of the blend with amines are classically worse than a simple mixing law would predict.

  15. Enhanced formaldehyde-vapor adsorption capacity of polymeric amine-incorporated aminosilicas.

    Science.gov (United States)

    Nomura, Akihiro; Jones, Christopher W

    2014-05-19

    Airborne formaldehyde, which is a highly problematic volatile organic compound (VOC) pollutant, is adsorbed by polymeric amine-incorporated silicas (aminosilicas), and the factors that affect the adsorption performance are systematically investigated. Three different types of polymeric amines 1) poly(ethyleneimine) branched (PEIBR); 2) poly(ethyleneimine) linear (PEILI); and 3) poly(allylamine) (PAA) are impregnated into two types of porous silicas [SBA-15 and mesocellular foam (MCF) silicas] with systematic changes of the amine loadings. The adsorption results demonstrate that the adsorption capacity increases along with the amine loading until the polymeric amines completely fill the silica pores. This results in the MCF silica, which has a larger pore volume and hence can accommodate more polymeric amine before completely filling the pore, giving materials that adsorb more formaldehyde, with the largest adsorption capacity, q, of up to 5.7 mmolHCHO  g(-1) among the samples studied herein. Of the three different types of polymers, PAA, comprised of 100 % primary amines, showed the highest amine efficiency μ (mmolHCHO/mmolN) for capturing formaldehyde. The chemical structures of the adsorbed formaldehyde are analyzed by (13)C cross-polarization magic-angle spinning (CP-MAS) NMR, and it is demonstrated that the adsorbed formaldehyde is chemically attached to the aminosilica surface, forming hemiaminal and imine species. Because the chemical adsorption of formaldehyde forms covalent bonds, it is not desorbed from the aminosilicas below 130 °C based on temperature-programed-desorption (TPD) analysis. The high formaldehyde-adsorption capacity and stability of the trapped formaldehyde on the amine surface in this study reveal the potential utility of aminosilicas as formaldehyde abatement materials.

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

    DEFF Research Database (Denmark)

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

    2012-01-01

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

  17. Microwave-assisted one step synthesis of 8-arylmethyl-9H-purin-6-amines.

    Science.gov (United States)

    Tao, Hui; Kang, Yanlong; Taldone, Tony; Chiosis, Gabriela

    2009-01-15

    Molecular chaperone heat shock protein 90 (Hsp90) is an important target in cancer and neurodegenerative diseases, and has rapidly become the focus of several drug discovery efforts. Among small molecule Hsp90 inhibitors with clinical applicability are derivatives of 8-arylmethyl-9H-purin-6-amine class. Here we report the use of microwave-assisted chemistry for the successful one-pot delivery of 8-arylmethyl-9H-purin-6-amines. We discuss the applicability as well as the limitations of this method towards the creation of a large chemical diversity in the 8-arylmethyl-9H-purin-6-amine series.

  18. Reduction of Biogenic Amines during Miso Fermentation by Lactobacillus plantarum as a Starter Culture.

    Science.gov (United States)

    Lee, Yi-Chen; Kung, Hsien-Feng; Huang, Ya-Ling; Wu, Chien-Hui; Huang, Yu-Ru; Tsai, Yung-Hsiang

    2016-09-01

    Lactobacillus plantarum D-103 isolated from a miso product that possesses amine-degrading activity was used as a starter culture in miso fermentation (25°C for 120 days) in this study. The salt content in control samples (without starter culture) and inoculated samples (inoculated with L. plantarum D-103) remained constant at 10.4% of the original salt concentration throughout fermentation, whereas the pH value decreased from 6.2 to 4.6 during fermentation. The inoculated samples had significantly lower (P culture with amine-degrading activity in miso products was effective in reducing the accumulation of biogenic amines.

  19. ORGANIC CHEMISTRY. Catalytic asymmetric hydroamination of unactivated internal olefins to aliphatic amines.

    Science.gov (United States)

    Yang, Yang; Shi, Shi-Liang; Niu, Dawen; Liu, Peng; Buchwald, Stephen L

    2015-07-01

    Catalytic assembly of enantiopure aliphatic amines from abundant and readily available precursors has long been recognized as a paramount challenge in synthetic chemistry. Here, we describe a mild and general copper-catalyzed hydroamination that effectively converts unactivated internal olefins—an important yet unexploited class of abundant feedstock chemicals—into highly enantioenriched α-branched amines (≥96% enantiomeric excess) featuring two minimally differentiated aliphatic substituents. This method provides a powerful means to access a broad range of advanced, highly functionalized enantioenriched amines of interest in pharmaceutical research and other areas.

  20. Partial amination of cationic exchange resins and its application in the hydration of butene

    Institute of Scientific and Technical Information of China (English)

    Deren Fang; Wanzhong Ren; Hongying Lü; Hongtao Yang

    2012-01-01

    In this work,the amination of sulfonated polystyrene resin with alkyl secondary amine is investigated.The catalytic activities of the modified resins are determined through the hydration of 1-butene.The optimum chain length and the best range of amination rate are determined.It is found that the single-pass conversion of 1-butene was raised 2% on average,and the relative activity was increased over 30% after modification.A hypothesis about the enhancement of catalytic activities by the inclusion of alkyl chain to wrap up the butene molecule is proposed.

  1. Catalytic intermolecular amination of C-H bonds: method development and mechanistic insights.

    Science.gov (United States)

    Fiori, Kristin Williams; Du Bois, J

    2007-01-24

    Reaction methodology for intermolecular C-H amination of benzylic and 3 degrees C-H bonds is described. This process uses the starting alkane as the limiting reagent, gives optically pure tetrasubstituted amines through stereospecific insertion into enantiomeric 3 degrees centers, displays high chemoselectivity for benzylic oxidation, and enables the facile preparation of isotopically enriched 15N-labeled compounds. Access to substituted amines, amino alcohols, and diamines is thereby made possible in a single transformation. Important information relevant to understanding the initial steps in the catalytic cycle, reaction chemoselectivity, the nature of the active oxidant, and pathways for catalyst inactivation has been gained through mechanistic analysis; these studies are also presented.

  2. Solid amine-boranes as high performance hypergolic hybrid rocket fuels

    Science.gov (United States)

    Pfeil, Mark A.

    Hypergolic hybrid rockets have the potential of providing systems that are simple, reliable, have high performance, and allow for energy management. Such a propulsion system can be applied to fields that need a single tactical motor with flexible mission requirements of either high speed to target or extended loitering. They also provide the possibility for alternative fast response dynamic altitude control systems if ignition delays are sufficiently short. Amines are the traditional fuel of choice when selecting a hypergolic combination as these tend to react readily with both nitric acid and dinitrogen tertroxide based oxidizers. It has been found that the addition of a borane adduct to an amine fuel tends to reduce the ignition delay by up to an order of magnitude with white fuming nitric acid (WFNA). The borane addition has resulted in fuels with very short ignition delays between 2-10 ms - the fastest times for an amine based fuel reacting with nitric acid based oxidizers. The incorporation of these amine-boranes, specifically ethylenediamine bisborane (EDBB), into various fuel binders has also been found to result in ignition delays between 3-10 ms - the fastest times again for amine based fuels. It was found that the addition of a borane to an amine increased theoretical performance of the amine resulting in high performance fuels. The amine-borane/fuel binder combinations also produced higher theoretical performance values than previously used hypergolic hybrid rockets. Some of the theoretical values are on par or higher than the current toxic liquid hypergolic fuels, making amine boranes an attractive replacement. The higher performing amine-borane/fuel binder combinations also have higher performance values than the traditional rocket fuels, excluding liquid hydrogen. Thus, amine-borane based fuels have the potential to influence various area in the rocket field. An EDBB/ferrocene/epoxy fuel was tested in a hypergolic hybrid with pure nitric acid as the

  3. Strong Room-Temperature Photoluminescence from the Novel Adduct of C60 with Aliphatic Amines

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Strong room-temperature photoluminescence from the adducts of C60 reacting with five different aliphatic amines, namely propylethylamine (PPA), n-butyl amine (BTA), n-heptylamine (HPA) and dodecylamine (DDA) and diethylamine (DEA), was firstly found from their toluene solution at relatively shorter wavelength around 519 nm.The fluorescence intensity has a good correlation with the length of n-alkyl group chain, the steric position and concentration of different amines and setting of solution as well as the UV-radiation. Their fluorescence quenching by concentration and by aromatic electron-donor N,N-dimethylaniline (DMA) were first investigated and determined.

  4. Natural amines inhibit activation of human plasmacytoid dendritic cells through CXCR4 engagement

    Science.gov (United States)

    Smith, Nikaïa; Pietrancosta, Nicolas; Davidson, Sophia; Dutrieux, Jacques; Chauveau, Lise; Cutolo, Pasquale; Dy, Michel; Scott-Algara, Daniel; Manoury, Bénédicte; Zirafi, Onofrio; McCort-Tranchepain, Isabelle; Durroux, Thierry; Bachelerie, Françoise; Schwartz, Olivier; Münch, Jan; Wack, Andreas; Nisole, Sébastien; Herbeuval, Jean-Philippe

    2017-01-01

    Plasmacytoid dendritic cells (pDC) are specialized in secretion of type I interferon in response to pathogens. Here we show that natural monoamines and synthetic amines inhibit pDC activation by RNA viruses. Furthermore, a synthetic analogue of histamine reduces type I interferon production in a mouse model of influenza infection. We identify CXC chemokine receptor 4 (CXCR4) as a receptor used by amines to inhibit pDC. Our study establishes a functional link between natural amines and the innate immune system and identifies CXCR4 as a potential ‘on-off' switch of pDC activity with therapeutic potential. PMID:28181493

  5. Organocatalyzed Asymmetric α-Oxidation, α-Aminoxylation and α-Amination of Carbonyl Compounds

    Directory of Open Access Journals (Sweden)

    Worawan Bhanthumnavin

    2010-02-01

    Full Text Available Organocatalytic asymmetric α-oxidation and amination reactions of carbonyl compounds are highly useful synthetic methodologies, especially in generating chiral building blocks that previously have not been easily accessible by traditional methods. The concept is relatively new and therefore the list of new catalysts, oxidizing and aminating reagents, as well as new substrates, are expanding at an amazing rate. The scope of this review includes new reactions and catalysts, mechanistic aspects and synthetic applications of α-oxidation, hydroxylation, aminoxylation, amination, hydrazination, hydroxyamination and related α-heteroatom functionalization of aldehydes, ketones and related active methylene compounds published during 2005–2009.

  6. Catalytic Enantioselective Electrophilic Aminations of Acyclic α-Alkyl β-Carbonyl Nucleophilies.

    Science.gov (United States)

    Liu, Xiaofeng; Sun, Bingfeng; Deng, Li

    2009-06-01

    Highly enantioselective aminations of acyclic α-alkyl β-keto thioesters and trifluoroethyl α-methyl α-cyanoacetate (12) with as low as 0.05 mol % of a bifunctional cinchona alkaloid catalyst were established. This ability to afford highly enantioselectivity for the amination of α-alkyl β-carbonyl compounds renders the 6'-OH cinchona alkaloid-catalyzed amination applicable for the enantioselective synthesis of acyclic chiral compounds bearing N-substituted quaternary stereocenters. The synthetic application of this reaction is illustrated in a concise asymmetric synthesis of α-methylserine, a key intermediate previously utilized in the total synthesis of a small molecule immunomodulator, conagenin.

  7. An improved reagent for determination of aliphatic amines with fluorescence and online atmospheric chemical ionization-mass spectrometry identification

    Energy Technology Data Exchange (ETDEWEB)

    You Jinmao, E-mail: Jmyou6304@163.com [Northwest Plateau Institute of Biology, Chinese Academy of Sciences, Xining, 810001 (China) and Key Laboratory of Life-Organic Analysis, College of Chemistry Science, Qufu Normal University, Qufu Shandong, 273165 (China); Song Cuihua; Yan Tao [Key Laboratory of Life-Organic Analysis, College of Chemistry Science, Qufu Normal University, Qufu Shandong, 273165 (China); Sun Zhiwei [Northwest Plateau Institute of Biology, Chinese Academy of Sciences, Xining, 810001 (China); Graduate University of Chinese Academy of Sciences, Beijing, 100049 (China); Li Yulin; Suo Yourui [Northwest Plateau Institute of Biology, Chinese Academy of Sciences, Xining, 810001 (China)

    2010-01-18

    An improved reagent named 2-[2-(dibenzocarbazole)-ethoxy] ethyl chloroformate (DBCEC-Cl) for the determination of aliphatic amines by high-performance liquid chromatography (HPLC) with fluorescence detection and post-column online atmospheric chemical ionization-mass spectrometry (APCI-MS) identification has been developed. DBCEC-Cl could easily and quickly label aliphatic amines. Derivatives were stable enough to be efficiently analyzed by HPLC and showed an intense protonated molecular ion corresponding m/z [M+H]{sup +} under APCI-MS in positive-ion mode. The ratios for fluorescence responses were I{sub DBCEC-amine}/I{sub BCEC-amine} = 1.02-1.60; I{sub DBCEC-amine}/I{sub BCEOC-amine} = 1.30-2.57; and I{sub DBCEC-amine}/I{sub FMOC-amine} = 2.20-4.12 (here, I was relative fluorescence intensity). The ratios for MS responses were IC{sub DBCEC-amine}/IC{sub BCEC-amine} = 4.16-29.31 and IC{sub DBCEC-amine}/IC{sub BCEOC-amine} = 1.23-2.47 (Here, IC: APCI-MS ion current intensity). Detection limits calculated from 0.0244 pmol injection, at a signal-to-noise ratio of 3, were 0.3-3.0 fmol. The relative standard deviations for within-day determination (n = 6) were 0.045-0.081% for retention time and 0.86-1.03% for peak area for the tested aliphatic amines. The mean intra- and inter-assay precision for all amine levels were <3.64% and 4.67%, respectively. The mean recoveries ranged from 96.9% to 104.7% with their standard deviations in the range of 1.80-2.70 (RSDs%). Excellent linear responses were observed with coefficients of >0.9991.

  8. Can creatine supplementation form carcinogenic heterocyclic amines in humans?

    Science.gov (United States)

    Pereira, Renato Tavares dos Santos; Dörr, Felipe Augusto; Pinto, Ernani; Solis, Marina Yazigi; Artioli, Guilherme Giannini; Fernandes, Alan Lins; Murai, Igor Hisashi; Dantas, Wagner Silva; Seguro, Antônio Carlos; Santinho, Mirela Aparecida Rodrigues; Roschel, Hamilton; Carpentier, Alain; Poortmans, Jacques Remi; Gualano, Bruno

    2015-09-01

    There is a long-standing concern that creatine supplementation could be associated with cancer, possibly by facilitating the formation of carcinogenic heterocyclic amines (HCAs). This study provides compelling evidence that both low and high doses of creatine supplementation, given either acutely or chronically, does not cause a significant increase in HCA formation. HCAs detection was unrelated to creatine supplementation. Diet was likely to be the main factor responsible for HCAs formation after either placebo (n = 6) or creatine supplementation (n = 3). These results directly challenge the recently suggested biological plausibility for the association between creatine use and risk of testicular germ cell cancer. Creatine supplementation has been associated with increased cancer risk. In fact, there is evidence indicating that creatine and/or creatinine are important precursors of carcinogenic heterocyclic amines (HCAs). The present study aimed to investigate the acute and chronic effects of low- and high-dose creatine supplementation on the production of HCAs in healthy humans (i.e. 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (8-MeIQx), 2-amino-(1,6-dimethylfuro[3,2-e]imidazo[4,5-b])pyridine (IFP) and 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline (4,8-DiMeIQx)). This was a non-counterbalanced single-blind crossover study divided into two phases, in which low- and high-dose creatine protocols were tested. After acute (1 day) and chronic supplementation (30 days), the HCAs PhIP, 8-MeIQx, IFP and 4,8-DiMeIQx were assessed through a newly developed HPLC-MS/MS method. Dietary HCA intake and blood and urinary creatinine were also evaluated. Out of 576 assessments performed (from 149 urine samples), only nine (3 from creatine and 6 from placebo) showed quantifiable levels of HCAs (8-MeIQx: n = 3; 4,8-DiMeIQx: n = 2; PhIP: n = 4). Individual analyses revealed that diet rather than creatine supplementation was

  9. Biogenic amine accumulation in silver carp sausage inoculated with Lactobacillus plantarum plus Saccharomyces cerevisiae.

    Science.gov (United States)

    Nie, Xiaohua; Zhang, Qilin; Lin, Shengli

    2014-06-15

    The effect of an amine-negative mixed starter culture (Lactobacillus plantarum ZY40 plus Saccharomyces cerevisiae JM19) on biogenic amine accumulation in fermented silver carp sausage was studied. Microbial counts, pH, titratable acid and free amino acids were also determined. Putrescine, cadaverine and tyramine were the main amines formed during sausage fermentation. The contents of putrescine and cadaverine were greatly reduced by the addition of L. plantarum ZY40 plus S. cerevisiae JM19, whereas tyramine accumulation was enhanced as compared to the control batch. Histamine and spermidine were not affected by the mixed starter culture, and their levels varied slightly throughout the fermentation. Besides, no positive correction between pH, free amino acid content and biogenic amine accumulation were found.

  10. Aliphatic amine responsive organogel system based on a simple naphthalimide derivative.

    Science.gov (United States)

    Cao, Xinhua; Zhang, Tingting; Gao, Aiping; Li, Keli; Cheng, Qiuli; Song, Lijuan; Zhang, Min

    2014-09-07

    A new gelator 1 based on a simple naphthalimide derivative was synthesized and fully characterized. It was found that the organogel 1 was formed only in a mixed solvent of methanol and H2O (1/1, v/v). The organogel was thoroughly characterized by using various microscopic techniques including field-emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), and UV-vis, fluorescence and Fourier transform infrared (FTIR) spectroscopy. Hydrogen bonds were the main driving force for the organogel formation. Interestingly, the organogel 1 exhibited the ability to distinguish aliphatic amines from aromatic amines. The gel state and fluorescence emission intensity were both changed after two minutes after the addition of aliphatic amines. This organogel system could be applied in the detection of aliphatic amine pollutants.

  11. Biogenic amines formation in Streptococcus thermophilus isolated from home-made natural yogurt.

    Science.gov (United States)

    Gezginc, Yekta; Akyol, Ismail; Kuley, Esmeray; Özogul, Fatih

    2013-05-01

    Twelve different biogenic amines formation in 58 isolates of Streptococcus thermophilus from home-made natural yogurt were investigated in histidine (HDB) and lysine decarboxylase broth (LDB). All S. thermophilus isolates had an ability to produce twelve different biogenic amines in HDB and LDB. Most of the S. thermophilus isolates formed low amounts of histamine (1-50 mg/L) from histidine. Apart from one isolate, S. thermophilus produced tyramine at low (47 isolates) and medium (10 isolates) levels. The amount of each specific biogenic amine produced by S. thermophilus was generally lower than 100 mg L(-1). Also, the presence of hdcA gene was investigated using PCR technique and relation between gene and histamine production was conducted in S. thermophilus isolates. This study showed that most of the S. thermophilus isolates have the ability to form biogenic amines, especially histamine, and tyramine, which is an important consideration when selecting strains as starter cultures.

  12. Enhancement of CO2 Affinity in a Polymer of Intrinsic Microporosity by Amine Modification.

    Science.gov (United States)

    Mason, Christopher R; Maynard-Atem, Louise; Heard, Kane W J; Satilmis, Bekir; Budd, Peter M; Friess, Karel; Lanc̆, Marek; Bernardo, Paola; Clarizia, Gabriele; Jansen, Johannes C

    2014-02-11

    Nitrile groups in the polymer of intrinsic microporosity PIM-1 were reduced to primary amines using borane complexes. In adsorption experiments, the novel amine-PIM-1 showed higher CO2 uptake and higher CO2/N2 sorption selectivity than the parent polymer, with very evident dual-mode sorption behavior. In gas permeation with six light gases, the individual contributions of solubility and diffusion to the overall permeability was determined via time-lag analysis. The high CO2 affinity drastically restricts diffusion at low pressures and lowers CO2 permeability compared to the parent PIM-1. Furthermore, the size-sieving properties of the polymer are increased, which can be attributed to a higher stiffness of the system arising from hydrogen bonding of the amine groups. Thus, for the H2/CO2 gas pair, whereas PIM-1 favors CO2, amine-PIM-1 shows permselectivity toward H2, breaking the Robeson 2008 upper bound.

  13. Biogenic amines degradation by malolactic bacteria: towards a potential application in wine

    Directory of Open Access Journals (Sweden)

    Vittorio eCapozzi

    2012-04-01

    Full Text Available Biogenic amines in wine represent a toxicological risk for the health of the consumer, with several trade implications. In this study 26 strains of Lactobacillus plantarum were analysed for their ability to degrade biogenic amines commonly found during wine fermentation. Two strains of L. plantarum were selected in reason of their ability to degrade putrescine and tyramine. The degradation was assessed in vitro, both in presence of the biogenic amines and in presence of the specific chemical precursor and of producer bacteria. The two L. plantarum biotypes were found capable to work synergically. In addition, the survival in wine-like medium and the aptitude to degrade malic acid after alcoholic fermentation of the selected L. plantarum strains was analysed. Our results suggest the potential application of wine L. plantarum strains to design malolactic starter cultures able to degrade biogenic amines in wine.

  14. CAN Catalyzed Preparation of β-Enamino Ketones from Amines and Acetylacetone

    Institute of Scientific and Technical Information of China (English)

    Zheng DUAN; Ting LI; Xue Jie XUAN; Yang Jie WU

    2006-01-01

    A variety of β-enamino ketones were synthesized in high to excellent yields by reacting acetylacetone with amines in the presence of a catalytic amount of cerium(Ⅳ) ammonium nitrate(CAN) under ultrasonic irradiation.

  15. Grafting of Amines on Ethanol-Extracted SBA-15 for CO2 Adsorption

    Directory of Open Access Journals (Sweden)

    Yuhan Sun

    2013-03-01

    Full Text Available SBA-15 prepared via ethanol extraction for template removing was grafted with three kinds of amine precursors (mono-, di-, tri-aminosilanes to synthesis new CO2 adsorbents. The SBA-15 support and the obtained adsorbents were characterized by X-ray diffraction (XRD, small-angle X-ray scattering (SAXS, N2 adsorption/desorption, thermogravimetry (TG, elemental analysis, Fourier transform infrared (FTIR spectrometry, scanning electron microscopy (SEM and transmission electron microscopy (TEM. It was found that, except higher silanol density, the ethanol-extracted SBA-15 support possessed a more regular mesophase and thicker walls than traditionally calcined samples, leading to a good stability of the adsorbent under steam treatment. The adsorption capacity of different amine-grafted samples was found to be influenced by not only the surface amine density, but also their physiochemical properties. These observations provide important support for further studies of applying amine-grafted adsorbents in practical CO2 capture process.

  16. A Selection of Amine Sorbents for CO2 Capture from Flue Gases

    Directory of Open Access Journals (Sweden)

    Wilk Andrzej

    2015-03-01

    Full Text Available Amine absorption processes are widely used in the industry to purify refinery gases, process gases or natural gas. Recently, amine absorption has also been considered for CO2 removal from flue gases. It has a number of advantages, but there is one major disadvantage - high energy consumption. This can be reduced by using an appropriate sorbent. From a group of several dozen solutions, three amine sorbents were selected based on primary, tertiary and sterically hindered amines. The solutions were used to test CO2 absorption capacity, absorption kinetics and heat of CO2 absorption. Additional tests were performed on the actual absorber-desorber system to indicate the most appropriate sorbent for capturing CO2 from flue gases.

  17. Flotation behavior of four dodecyl tertiary amines as collectors of diaspore and kaolinite

    Institute of Scientific and Technical Information of China (English)

    Changmiao Liu; Feng Ansheng; GUO Zhenxu; Cao Xuefeng; Hu Yuehua

    2011-01-01

    The flotation of diaspore and kaolinite by one of a series of tertiary amines (DRN, DEN, DPN and DBN) was investigated. The tertiary amines show better floating recovery for kaolinite compared to diaspore. The maximum recovery D-value is 45% over a pH range from 3 to 8. FT-IR spectra confirm the presence of hydroxyl groups on the surface of kaolinite and diaspore. Zeta potential measurements show that the mineral surfaces are negatively charged over a wide pH range. Ionization of hydroxyl groups mainly accounts for the surface charging mechanism. The adsorption of tertiary amines onto the mineral surface is due mainly to electrostatic effects and the difference in electrostatic effect between a collector and the two minerals can explain the flotation separation. Inductive electronic and steric effects from the substituent groups result in different collecting powers for the four tertiary amines.

  18. Anionic Synthesis of Primary and Secondary Amine-Functionalized Polymers Using Imine Chemistry

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A review of methods for the anionic synthesis of well-defined, amine-functional-ized polymers using imines as functionalizing agents is provided. The disparate results in theliterature regarding functionalizations with N-(benzylidene)trimethylsilylamine to form pri-mary amine functionalized polymers are discussed ; the efficiency of functionalization dependson the molecular weight of the polymeric organolithium(PLi). Efficient functionalizationsare observed for PLi with Kn>10 000 g/mol. The poor functionalization yields using ke-timines with enolizable hydrogens is explained. The use of N-trimethylsi-lyldiphenylcarbimide as a quantitative primary amine functionalizing reagent is described.Recent results on the anionic synthesis of secondary amine-functionalized polymers using N-(benzylidene)methylamine as the functionalization agent are presented.

  19. Synthesis of highly functionalized pyrroles from primary amines and activated acetylenes in water

    Institute of Scientific and Technical Information of China (English)

    S.Zahra Sayyed-Alangi; Zinatossadat Hossaini; Faramarz Rostami-Charati

    2012-01-01

    Stable derivatives of pyrroles were prepared using multicomponent reactions of dialkyl acetylenedicarboxylate,primary amine and propiolate in the presence of N-methylimidazole in water at room temperature in good yields.

  20. The Prowess of Photogenerated Amine Radical Cations in Cascade Reactions: From Carbocycles to Heterocycles.

    Science.gov (United States)

    Morris, Scott A; Wang, Jiang; Zheng, Nan

    2016-09-20

    Cascade reactions represent a class of ideal organic reactions because they empower efficiency, elegance, and novelty. However, development of cascade reactions remains a daunting task for synthetic chemists. Radicals are known to be well suited for cascade reactions. Compared with widely used carbon-based radicals, nitrogen-based radicals, such as neutral aminyl radicals and protonated aminyl radicals (amine radical cations), are underutilized, although they are behind some notable synthetic methods such as the Hofmann-Löffler-Freytag reaction. The constraint on their usage is generally attributed to the limited number of available stable precursors. Since amine radical cations offer increased reactivity and selectivity in chemical transformations compared with neutral aminyl radicals, their generation is of utmost importance. Recently, a surge of reports has been revealed using visible light photoredox catalysis. It has been demonstrated that amines can act as an electron donor in a reductive quenching cycle while the amine itself is oxidized to the amine radical cation. Although a number of methods exist to generate amine radical cations, the photochemical formation of these species offers many practical advantages. In this Account, we discuss our journey to the development of annulation reactions with various π-bonds and electrophilic addition reactions to alkenes using photogenerated amine radical cations. Various carbocycles and heterocycles are produced by these reactions. In our annulation work, we first show that single electron photooxidation of cyclopropylanilines to the amine radical cations triggers ring opening of the strained carbocycle, producing distonic radical cations. These odd-electron species are shown to react with alkenes and alkynes to yield the corresponding cyclopentanes and cyclopentenes in an overall redox neutral process. Further development of this annulation reaction allows us to achieve the [4 + 2] annulation of cyclobutylanilines

  1. New procedure of selected biogenic amines determination in wine samples by HPLC

    Energy Technology Data Exchange (ETDEWEB)

    Piasta, Anna M.; Jastrzębska, Aneta, E-mail: aj@chem.uni.torun.pl; Krzemiński, Marek P.; Muzioł, Tadeusz M.; Szłyk, Edward

    2014-06-27

    Highlights: • We proposed new procedure for derivatization of biogenic amines. • The NMR and XRD analysis confirmed the purity and uniqueness of derivatives. • Concentration of biogenic amines in wine samples were analyzed by RP-HPLC. • Sample contamination and derivatization reactions interferences were minimized. - Abstract: A new procedure for determination of biogenic amines (BA): histamine, phenethylamine, tyramine and tryptamine, based on the derivatization reaction with 2-chloro-1,3-dinitro-5-(trifluoromethyl)-benzene (CNBF), is proposed. The amines derivatives with CNBF were isolated and characterized by X-ray crystallography and {sup 1}H, {sup 13}C, {sup 19}F NMR spectroscopy in solution. The novelty of the procedure is based on the pure and well-characterized products of the amines derivatization reaction. The method was applied for the simultaneous analysis of the above mentioned biogenic amines in wine samples by the reversed phase-high performance liquid chromatography. The procedure revealed correlation coefficients (R{sup 2}) between 0.9997 and 0.9999, and linear range: 0.10–9.00 mg L{sup −1} (histamine); 0.10–9.36 mg L{sup -1} (tyramine); 0.09–8.64 mg L{sup −1} (tryptamine) and 0.10–8.64 mg L{sup −1} (phenethylamine), whereas accuracy was 97%–102% (recovery test). Detection limit of biogenic amines in wine samples was 0.02–0.03 mg L{sup −1}, whereas quantification limit ranged 0.05–0.10 mg L{sup −1}. The variation coefficients for the analyzed amines ranged between 0.49% and 3.92%. Obtained BA derivatives enhanced separation the analytes on chromatograms due to the inhibition of hydrolysis reaction and the reduction of by-products formation.

  2. Formation rates, stability and reactivity of sulfuric acid - amine clusters predicted by computational chemistry

    Science.gov (United States)

    Kurtén, Theo; Ortega, Ismael; Kupiainen, Oona; Olenius, Tinja; Loukonen, Ville; Reiman, Heidi; McGrath, Matthew; Vehkamäki, Hanna

    2013-04-01

    Despite the importance of atmospheric particle formation for both climate and air quality, both experiments and non-empirical models using e.g. sulfuric acid, ammonia and water as condensing vapors have so far been unable to reproduce atmospheric observations using realistic trace gas concentrations. Recent experimental and theoretical evidence has shown that this mystery is likely resolved by amines. Combining first-principles evaporation rates for sulfuric acid - dimethylamine clusters with cluster kinetic modeling, we show that even sub-ppt concentrations of amines, together with atmospherically realistic concentrations of sulfuric acid, result in formation rates close to those observed in the atmosphere. Our simulated cluster formation rates are also close to, though somewhat larger than, those measured at the CLOUD experiment in CERN for both sulfuric acid - ammonia and sulfuric acid - dimethylamine systems. A sensitivity analysis indicates that the remaining discrepancy for the sulfuric acid - amine particle formation rates is likely caused by steric hindrances to cluster formation (due to alkyl groups of the amine molecules) rather than by significant errors in the evaporation rates. First-principles molecular dynamic and reaction kinetic modeling shed further light on the microscopic physics and chemistry of sulfuric acid - amine clusters. For example, while the number and type of hydrogen bonds in the clusters typically reach their equilibrium values on a picosecond timescale, and the overall bonding patterns predicted by traditional "static" quantum chemical calculations seem to be stable, the individual atoms participating in the hydrogen bonds continuously change at atmospherically realistic temperatures. From a chemical reactivity perspective, we have also discovered a surprising phenomenon: clustering with sulfuric acid molecules slightly increases the activation energy required for the abstraction of alkyl hydrogens from amine molecules. This implies

  3. Quaternary Organic Amines Inhibit Na,K Pump Current in a Voltage-dependent Manner

    OpenAIRE

    2004-01-01

    The effects of organic quaternary amines, tetraethylammonium (TEA) chloride and benzyltriethylammonium (BTEA) chloride, on Na,K pump current were examined in rat cardiac myocytes superfused in extracellular Na+-free solutions and whole-cell voltage-clamped with patch electrodes containing a high Na+-salt solution. Extracellular application of these quaternary amines competitively inhibited extracellular K+ (K+ o) activation of Na,K pump current; however, the concentration for half maximal inh...

  4. Using aqueous ammonia in hydroaminomethylation reactions: ruthenium-catalyzed synthesis of tertiary amines.

    Science.gov (United States)

    Wu, Lipeng; Fleischer, Ivana; Zhang, Min; Liu, Qiang; Franke, Robert; Jackstell, Ralf; Beller, Matthias

    2014-12-01

    The direct synthesis of tertiary amines from ammonia and olefins is presented. Using a combination of Ru3 (CO)12 and 2-phosphino-substituted imidazole ligand as catalyst system allows for hydroaminomethylation reactions of bulk aliphatic and functionalized olefins. Tertiary amines are obtained in an atom-efficient domino process in moderate to good isolated yields (45-76%) with excellent regioselectivities (n/iso up to 99:1).

  5. A novel squaraine dye with squaramide as a scaffold and the colorimetric detection of amine

    Institute of Scientific and Technical Information of China (English)

    Chuan Guo Sun; Qian Lin; Nan Yan Fu

    2012-01-01

    A novel unsymmetrical squaramide-linked squaraine dye (SQ) has been synthesized through squaramide 3 and semisquaraine 6.The molecular structure of SQ has been characterized by 1H NMR,IR and MS.Due to the influence of the hydrogen bond and the solvent effect,SQ exhibits unique spectral properties compared with typical squaraine dyes.For its excellent ability of binding primary amine,SQ is a promising receptor of recognizing primary amine.

  6. Metabolism of biogenic amines in acute cerebral ischemia: Influence of systemic hyperglycemia

    Directory of Open Access Journals (Sweden)

    Milovanović Aleksandar

    2012-01-01

    Full Text Available Dopamine, norepinephrine and serotonin are biogenic amines which are transmitters of the central nervous system. The effects of ischemia on the brain parenchyma depends on many factors, such is the mechanism of blood flow interruption, velocity of the occurring blood flow interruption, duration of an ischemic episode, organization of anatomical structures of the brain blood vessels etc., which all influence the final outcome. During interruption of the brain circulation in experimental or clinical conditions, neurotransmitter metabolism, primarily of biogenic amines, is disturbed. Many researches with various experimental models of complete ischemia reported a decrease in the content of norepinephrine, dopamine and serotonin in the CNS tissue. It was proven that hyperglycemia can drastically increase cerebral injury followed by short-term cerebral ischemia. Considering the fact that biogenic amines (dopamine, norepinephrine and serotonin influence the size of neurologic damage, as well as the fact that in hyperglycemic conditions infarct size (from the morphological aspect is larger relative to normoglycemic status, the intention was to evaluate the role of biogenic amines in occurrence of damage in conditions of hyperglycemia, i.e. in the case of brain apoplexia in diabetics. Analysis of biogenic amines metabolism in states of acute hyperglycemia, as well as analysis of the effects of reversible and irreversible brain ischemia on metabolism of serotonin, dopamine and norepinephrine, showed that acute hyperglycemia slows down serotonin, dopamine and norepinephrine metabolism in the cerebral cortex and n. caudatus. Brain ischemia in normoglycemic animals by itself has no influence on biogenic amines metabolism, but the effect of ischemia becomes apparent during reperfusion. In recirculation, which corresponds to the occurrences in penumbra, release of biogenic amines is uncontrolled and increased. Brain ischemia in acute hyperglycemic animals

  7. Synthesis of periodic mesoporous organosilicas functionalized with different amine-organoalkoxysilanes via direct co-condensation

    Energy Technology Data Exchange (ETDEWEB)

    Suriyanon, Nakorn [International Postgraduate Programs in Environmental Management, Graduate School, Chulalongkorn University, Pathumwan, Bangkok 10330 (Thailand); Center of Excellence for Environmental and Hazardous Waste Management (EHWM), Pathumwan, Bangkok 10330 (Thailand); Punyapalakul, Patiparn [Center of Excellence for Environmental and Hazardous Waste Management (EHWM), Pathumwan, Bangkok 10330 (Thailand); Department of Environmental Engineering, Faculty of Engineering, Chulalongkorn University, Pathumwan, Bangkok 10330 (Thailand); Ngamcharussrivichai, Chawalit, E-mail: Chawalit.Ng@Chula.ac.th [Fuels Research Center, Department of Chemical Technology, Faculty of Science, Chulalongkorn University, Pathumwan, Bangkok 10330 (Thailand); Center of Excellence on Petrochemical and Materials Technology (PETROMAT), Chulalongkorn University, Pathumwan, Bangkok 10330 (Thailand)

    2015-01-15

    A series of amine-functionalized periodic mesoporous organosilicas (PMOs) were synthesized from bis(triethoxysilyl)ethane via surfactant-templating using supramolecular assemblies of hexadecyltrimethylammonium chloride under basic conditions. Functionalization of the PMO materials was performed via direct co-condensation in the presence of mono-, di- or tri-amine-organoalkoxysilanes. The effect of the type and concentration of the added organosilanes on the physicochemical properties of the functionalized PMOs were investigated. Thermogravimetric/differential thermal analysis (TG/DTA) and Fourier transform infrared spectroscopy (FTIR) confirmed the presence of the inorganic–organic hybrid framework functionalized with the amine groups. The total nitrogen content of the functionalized PMOs ranged from 0.26 to 1.27 mmol/g. The materials possessed a hexagonal lattice with the highly ordered mesostructure being preserved after the amine-functionalization as evidenced by X-ray diffraction (XRD) analysis and transmission electron microscopy (TEM). The N{sub 2} adsorption–desorption measurement revealed that the materials had high specific surface areas (963–1252 m{sup 2}/g) and a relatively high total pore volume (0.52–0.85 cm{sup 3}/g). The mesopore size and wall thickness of these materials varied in relation with the molecular size and the loading of the organosilanes. Moreover, the morphology of the PMO materials was increasingly transformed from irregular shaped particles to spheres with increasing amounts of amine-functional groups or with organo-functional groups with several amine units. - Highlights: • Periodic mesoporous organosilicas (PMOs) were functionalized via co-condensation. • Long-chain organosilane with three amine units was employed a precursor. • Hexagonal mesostructure of PMO was preserved at a 40 mol% loading level. • Amine-functionalized PMOs had a high surface area and total pore volume. • Their morphology depended on the

  8. The effect of water resistance in the primary coating by silane coupling agents and amine synergists

    Science.gov (United States)

    Kim, Min-Jeong; Min, Kyoungbeom; Kim, Sanghwan; Yoon, Jung-Woo; Kwak, Seungjo; Lee, Ji-hye; Oh, Sungkoog

    2008-11-01

    In order to clarify the relationship between the water resistance and compositional additives in the primary coating for optical fibers, we prepared various primary coatings that contained silane coupling agents in combination with amine synergists. We observed the appearance of the interface between glass and primary coating after soaking in water at 65° for 30 days. Water resistance was found to be heavily influenced by the content and type of silane coupling agents and amine synergists and their trends are reported.

  9. Stereoselective amination of racemic sec-alcohols through sequential application of laccases and transaminases

    OpenAIRE

    Martínez, Lía; Gotor,Vicente; Lavandera, Ivan

    2016-01-01

    A one-pot/two-step bienzymatic asymmetric amination of secondary alcohols is disclosed. The approach is based on a sequential strategy involving the use of a laccase/TEMPO catalytic system for the oxidation of alcohols into ketone intermediates, and their following transformation into optically enriched amines by using transaminases. Individual optimizations of the oxidation and biotransamination reactions have been carried out, studying later their applicability in a concurrent proc...

  10. Direct use of allylic alcohols for platinum-catalyzed monoallylation of amines.

    Science.gov (United States)

    Utsunomiya, Masaru; Miyamoto, Yoshiki; Ipposhi, Junji; Ohshima, Takashi; Mashima, Kazushi

    2007-08-16

    A new direct catalytic amination of allylic alcohols promoted by the combination of platinum and a large bite-angle ligand DPEphos was developed in which the allylic alcohol was effectively converted to a pi-allylplatinum intermediate without the use of an activating reagent. The use of the DPEphos ligand was essential for obtaining high catalyst activity and high monoallylation selectivity of primary amines, allowing the formation of a variety of monoallylation products in good to excellent yield.

  11. Role of L-alanine for redox self-sufficient amination of alcohols

    OpenAIRE

    Klatte, Stephanie; Wendisch, Volker F

    2015-01-01

    Background In white biotechnology biocatalysis represents a key technology for chemical functionalization of non-natural compounds. The plasmid-born overproduction of an alcohol dehydrogenase, an L-alanine-dependent transaminase and an alanine dehydrogenase allows for redox self-sufficient amination of alcohols in whole cell biotransformation. Here, conditions to optimize the whole cell biocatalyst presented in (Bioorg Med Chem 22:5578–5585, 2014), and the role of L-alanine for efficient amin...

  12. Expedient protocol for solid-phase synthesis of secondary and tertiary amines

    DEFF Research Database (Denmark)

    Olsen, Christian A; Witt, Matthias; Jaroszewski, Jerzy W

    2004-01-01

    [reaction: see text] An expedient solid-phase synthetic approach to secondary and tertiary amines was developed. The protocol employs conversion of resin-bound amino alcohols to the corresponding iodides, followed by iodide displacement with primary or secondary amines or with unprotected amino...... alcohols. This two-step procedure, affording products in good to excellent yields, is suitable for solid-phase synthesis of polyamines....

  13. Effect of critical process parameters on the synthesis of chiral amines

    DEFF Research Database (Denmark)

    Pirrung, Silvia; Lima Afonso Neto, Watson; Schwarze, Daniel

    equilibrium, the inhibition profiles for substrates and products but also on the possibilities for in-situ product removal (ISPR) and technologies for shifting the equilibrium. In a challenging process such as the synthesis of optically pure chiral amines using ω-transaminase, these decisions will have...... process parameters involved in the production of two chiral amines (S-methylbenzylamine and 3-amino-1-phenylbutane) (Figure 1) to demonstrate the effects of such decisions....

  14. Silicon Amine Reagents for the Photocatalytic Synthesis of Piperazines from Aldehydes and Ketones.

    Science.gov (United States)

    Hsieh, Sheng-Ying; Bode, Jeffrey W

    2016-05-06

    Silicon amine protocol (SLAP) reagents for photocatalytic cross-coupling with aldehydes and ketones to form N-unprotected piperazines have been developed. This blue light promoted process tolerates a wide range of heteroaromatic, aromatic, and aliphatic aldehydes and structurally and stereochemically complex SLAP reagents. It provides a tin-free alternative to SnAP (tin amine protocol) reagents for the synthesis of substituted piperazines.

  15. Development of system design information for carbon dioxide using an amine type sorber

    Science.gov (United States)

    Rankin, R. L.; Roehlich, F.; Vancheri, F.

    1971-01-01

    Development work on system design information for amine type carbon dioxide sorber is reported. Amberlite IR-45, an aminated styrene divinyl benzene matrix, was investigated to determine the influence of design parameters of sorber particle size, process flow rate, CO2 partial pressure, total pressure, and bed designs. CO2 capacity and energy requirements for a 4-man size system were related mathematically to important operational parameters. Some fundamental studies in CO2 sorber capacity, energy requirements, and process operation were also performed.

  16. Seasonal variation of aliphatic amines in marine sub-micrometer particles at the Cape Verde islands

    Directory of Open Access Journals (Sweden)

    C. Müller

    2009-07-01

    Full Text Available Monomethylamine (MA, dimethylamine (DMA and diethylamine (DEA were detected at non-negligible concentrations in sub-micrometer particles at the Cap Verde Atmospheric Observatory (CVAO located on the island of São Vicente in Cape Verde during algal blooms in 2007. The concentrations of these amines in five stage impactor samples ranged from 0 to 30 pg m−3 for MA, 130 to 360 pg m−3 for DMA and 5 to 110 pg m−3 for DEA during the spring bloom in May 2007 and 2 to 520 pg m−3 for MA, 100 to 1400 pg m−3 for DMA, 90 to 760 pg m−3 for DEA during an unexpected winter algal bloom in December 2007. Anomalously high Saharan dust deposition and intensive ocean layer deepening were found at the Atmospheric Observatory and the associated Ocean Observatory during algal bloom periods. The highest amine concentrations in fine particles (impactor stage 2, 0.14–0.42 μm indicates that amines are likely taken up from the gas phase into the acidic sub-micrometer particles. The contribution of amines to the organic carbon (OC content ranged from 0.2 to 2.5%C in the winter months, indicating the importance of this class of compounds to the carbon cycle in the marine environment. Furthermore, aliphatic amines originating from marine biological sources likely contribute significantly to the organic nitrogen in the marine atmosphere. The average contribution of the amines to the total detected nitrogen content in submicron particles can be non-negligible, especially in the winter months (0.1% N to 1.5% N in the sum of nitrate, ammonium and amines. This indicates that these smaller aliphatic amines can be important for the carbon and the nitrogen cycles in the remote marine environment.

  17. Conjugate Additions of Secondary Amines and Water to Allenyl Perfluoroalkyl Sulfones

    Institute of Scientific and Technical Information of China (English)

    WANG Xiao-Jin; LIN Yun; LIU Jin-Tao

    2006-01-01

    Preparation of allenyl perfluoroalkyl sulfones from perfluoroalkyl sulfinyl chlorides and their reactions with secondary amines and water were studied. At room temperature secondary amines reacted readily with allenyl perfluoroalkyl sulfones to give the corresponding enamine adducts, which underwent rearrangement to afford conjugate enamines in refluxing toluene. Good diastereoslectivities were observed in the addition of diethylamine to γ-ethyl-γ-methylallenyl perfluoroalkyl sulfones. In refluxing acetonitrile, water could also undergo the similar addition with allenyl perfluoroalkyl sulfones.

  18. A Photo Touch on Amines: New Synthetic Adventures of Nitrogen Radical Cations.

    Science.gov (United States)

    Maity, Soumitira; Zheng, Nan

    2012-08-01

    Amines have been used as sacrificial electron donors to reduce photoexcited Ru(II) or Ir(III) complexes, during which they are oxidized to nitrogen radical cations. Recently, the synthetic potential of these nitrogen radical cations have caught synthetic organic chemists' attention. They have been exploited in various transformations yielding a number of elegant methods for amine synthesis. This article highlights recent developments on nitrogen radical cation chemistry under visible-light photocatalysis.

  19. Seasonal variation of aliphatic amines in marine sub-micrometer particles at the Cape Verde islands

    Science.gov (United States)

    Müller, C.; Iinuma, Y.; Karstensen, J.; van Pinxteren, D.; Lehmann, S.; Gnauk, T.; Herrmann, H.

    2009-12-01

    Monomethylamine (MA), dimethylamine (DMA) and diethylamine (DEA) were detected at non-negligible concentrations in sub-micrometer particles at the Cap Verde Atmospheric Observatory (CVAO) located on the island of São Vicente in Cape Verde during algal blooms in 2007. The concentrations of these amines in five stage impactor samples ranged from 0-30 pg m-3 for MA, 130-360 pg m-3 for DMA and 5-110 pg m-3 for DEA during the spring bloom in May 2007 and 2-520 pg m-3 for MA, 100-1400 pg m-3 for DMA and 90-760 pg m-3 for DEA during an unexpected winter algal bloom in December 2007. Anomalously high Saharan dust deposition and intensive ocean layer deepening were found at the Atmospheric Observatory and the associated Ocean Observatory during algal bloom periods. The highest amine concentrations in fine particles (impactor stage 2, 0.14-0.42 μm) indicate that amines are likely taken up from the gas phase into the acidic sub-micrometer particles. The contribution of amines to the organic carbon (OC) content ranged from 0.2-2.5% C in the winter months, indicating the importance of this class of compounds to the carbon cycle in the marine environment. Furthermore, aliphatic amines originating from marine biological sources likely contribute significantly to the nitrogen content in the marine atmosphere. The average contribution of the amines to the detected nitrogen species in sub-micrometer particles can be non-negligible, especially in the winter months (0.1% N-1.5% N in the sum of nitrate, ammonium and amines). This indicates that these smaller aliphatic amines can be important for the carbon and the nitrogen cycles in the remote marine environment.

  20. Differences between biogenic amine detection by HPLC methods using OPA and dansyl derivates.

    Science.gov (United States)

    Alberto, María R; Arena, Mario E; De Nadra, María C Manca

    2004-01-01

    Biogenic amines can be formed and degraded as a result of normal metabolic activity in animals, plants, and microorganisms and are usually produced by the decarboxylation of amino acids. Recent trends in food security are promoting an increasing search for trace compounds that can affect human health. Although they are present in fermented foods and beverages in low quantities, they exhibit interactions with normal human metabolism (e.g., having vasoactive or psychoactive properties) that justify the research on their presence in foods and the possible related toxicological effects that they may cause. Estimation of the biogenic amines histamine, tyramine, agmatine, putrescine, and cadaverine is important not only from the point of view of their toxicity, but also because they can be used as indicators of the degree of freshness or spoilage of food. Until recently, because of the difficulty in detecting and quantifying amines reliably we have had insufficient information about their occurrence in different types of foods and beverages. These problems are related to matrix interference (e.g., the presence of free amino acids) and the low levels at which the amines are found. Early techniques for the determination of biogenic amines in foods were based on thin-layer chromatography. More modern analytical techniques have since been developed that allow the acquisition of reliable quantitative data and better separation/resolution of various amines. The quantitative determination of biogenic amines is generally accomplished by overpressure-layer chromatography, high-performance liquid chromatography (HPLC), and gas chromatography. The use of reverse-phase column and precolumn derivatization was more efficient and faster than the conventional ion-exchange techniques. This study was conducted to evaluate two HPLC derivatization methods for quantitative determination of biogenic amines: the method described by Gonzales de Llano et al. for amino acid analysis and the

  1. Preparation and adsorption property of aminated cross linking microbeads of GMA/EGDMA for bilirubin

    Indian Academy of Sciences (India)

    Zhiping Chen; Baojiao Gao; Xiaofeng Yang

    2009-11-01

    Cross linking microbeads with a controllable diameter were synthesized by suspension copolymerization of the monomer glycidyl methacrylate (GMA) and the cross linking agent ethylene glycol dimethylacrylate (EGDMA). By the ring-opening reaction of the epoxy groups, the microbeads GMA/EGDMA were modified with different aminating agents and resulting in the aminated microbeads. The morphology of the microbeads was characterized by SEM. The adsorption property of aminated microbeads for bilirubin was investigated, and the effects of various factors, such as the chemical structures of the aminating agents, pH values of the medium and the presence of bovine serum albumin in the adsorption medium, on the adsorption property were examined. The experimental results show that the aminated microbeads have strong adsorption ability for bilirubin, and the isotherm adsorption behaviour is fitted to Freundlich equation satisfactorily. The adsorption ability of the aminated microbeads modified with hexanediamine is stronger than that of others, and the longer the molecule of multi-ethylene multiamine, the weaker the adsorption ability for bilirubin. The pH value of the medium affects the adsorption ability greatly, as pH = 6, the adsorption ability is strongest. In the presence of BSA, the microbeads still have a higher adsorption capacity towards bilirubin.

  2. Dynamics of CO 2 Adsorption on Amine Adsorbents. 2. Insights Into Adsorbent Design

    KAUST Repository

    Bollini, Praveen

    2012-11-21

    Packed bed breakthrough experiments are reported for commercial zeolite 13X and 3-aminopropyl-functionalized SBA-15 silica materials with three different amine loadings. Mass and heat transfer dynamics for all four materials are modeled successfully. Amine adsorbents with open pores are found to exhibit faster mass diffusion rates compared to zeolite 13X. When amine loading is increased by coupling aminopropyl groups, premature breakthrough combined with a long tail is observed. Contrary to conventional physisorbants, finite heat losses to the column wall do not explain the long breakthrough tail. A rate model that accounts for heterogeneity in diffusion was found to accurately capture the breakthrough shape of the high loading material. Batch uptake measurements support the hypothesis that slow diffusion through the polymer phase is what hampers adsorption kinetics in the high amine loading adsorbent. The results emphasize the importance of designing materials that are not overloaded with amine sites, as excessive amine loadings can lead to depressed adsorption kinetics and premature column breakthrough. © 2012 American Chemical Society.

  3. Managing your wine fermentation to reduce the risk of biogenic amine formation

    Directory of Open Access Journals (Sweden)

    Anita Yolandi Smit

    2012-03-01

    Full Text Available Biogenic amines are nitrogenous organic compounds produced in wine from amino acid precursors mainly by microbial decarboxylation. The concentration of biogenic amines that can potentially be produced is dependent on the amount of amino acid precursors in the medium, the presence of decarboxylase positive microorganisms and conditions that enable microbial or biochemical activity such as the addition of nutrients to support the alcoholic and malolactic fermentation (MLF inoculated starter cultures. MLF can be conducted using co-inoculation or inoculated after the completion of alcoholic fermentation (AF that may also affect the level of biogenic amine in the wine. This study focussed on the impact the addition of complex commercial yeast and bacterial nutrients and the use of different MLF inoculation scenarios could have on the production of biogenic amine in the wine. Results obtained with wine showed that in this study the amine that was influenced by nutrient addition was histamine. In the synthetic winemaking using 12 different treatments no clear tendencies were observed. It was shown that in certain conditions co-inoculation could reduce the amount of biogenic amines produced.

  4. Ambient pressure proton transfer mass spectrometry: detection of amines and ammonia.

    Science.gov (United States)

    Hanson, D R; McMurry, P H; Jiang, J; Tanner, D; Huey, L G

    2011-10-15

    An instrument to detect gaseous amines and ammonia is described, and representative data from an urban site and a laboratory setting are presented. The instrument, an Ambient pressure Proton transfer Mass Spectrometer (AmPMS), consists of a chemical ionization and drift region at atmospheric pressure coupled to a standard quadrupole mass spectrometer. Calibrations show that AmPMS sensitivity is good for amines, and AmPMS backgrounds were suitably determined by diverting sampled air through a catalytic converter. In urban air at a site in Atlanta, amines were detected at subpptv levels for methyl and dimethyl amine which were generally at a low abundance of ammonia were high, and data are very limited for these species. Improvements in detecting amines and ammonia from a smog chamber were evident due to improvements in AmPMS background determination; notably dimethyl amine and its OH oxidation products were followed along with impurity ammonia and other species. Future work will focus on accurate calibration standards and on improving the sample gas inlet.

  5. Study on biogenic amines in various dry salted fish consumed in China

    Science.gov (United States)

    Wu, Yanyan; Chen, Yufeng; Li, Laihao; Yang, Xianqing; Yang, Shaoling; Lin, Wanling; Zhao, Yongqiang; Deng, Jianchao

    2016-08-01

    This study was carried out to investigate the biogenic amines (BAs), physicochemical property and microorganisms in dry salted fish, a traditional aquatic food consumed in China. Forty three samples of dry salted fish were gathered from retail and wholesale markets and manufacturers, which had been produced in various regions in China. Cadaverine (CAD) and putrescine (PUT) were quantitatively the most common biogenic amines. About 14% of the samples exceeded the histamine content standards established by the FDA and/or EU. The highest histamine content was found in Silver pomfret ( Pampus argenteus) (347.79 mg kg-1). Five of forty three samples exceeded the acceptable content of TYR (100 mg kg-1), and 23.26% of dried-salted fish contained high contents of biogenic amines (above 600 mg kg-1). In addition, species, regions, pickling processes and drying methods made the physicochemical property, microorganisms and biogenic amines in dry salted fish to be different to some extents. The total plate count (TPC) was much higher than that of total halophilic bacteria in all samples. The biogenic amines, physicochemical property and microbiological counts exhibited large variations among samples. Furthermore, no significant correlation between biogenic amines and physicochemical property and TPC was observed. This study indicated that dry salted fish may still present healthy risk for BAs, depending on the processing methods, storage conditions among others.

  6. Effects of amines on formation of sub-3 nm particles and their subsequent growth

    Energy Technology Data Exchange (ETDEWEB)

    Yu H.; McGraw R.; Lee S.-H.

    2012-01-28

    Field observations and quantum chemical calculations suggest that amines can be important for formation of nanometer size particles. Amines and ammonia often have common atmospheric emission sources and the similar chemical and physical properties. While the effects of ammonia on aerosol nucleation have been previously investigated, laboratory studies of homogeneous nucleation involving amines are lacking. We have made kinetics studies of multicomponent nucleation (MCN) with sulfuric acid, water, ammonia and amines under conditions relevant to the atmosphere. Low concentrations of aerosol precursors were measured with chemical ionization mass spectrometers (CIMS) to provide constrained precursor concentrations needed for nucleation. Particle sizes larger than {approx}2 nm were measured with a nano-differential mobility analyzer (nano-DMA), and number concentrations of particles larger than {approx}1 nm were measured with a particle size magnifier (PSM). Our observations provide the laboratory evidence that amines indeed can participate in aerosol nucleation and growth at the molecular cluster level. The enhancement of particle number concentrations due to several atmospherically relevant amine compounds and ammonia were related to the basicity of these compounds, indicating that acid-base reactions may contribute to the formation of sub-3 nm particles.

  7. The Effect of Fatty Amine Chain Length on Synthesis Process of Inp/Zns Quantum Dots

    Directory of Open Access Journals (Sweden)

    Zahra Ranjbar Navazi

    2016-08-01

    Full Text Available Obtaining narrow size distribution through conventional methods used for quantum dots of group II-VI semiconductors is impractical in the case of III-V semiconductors speciallyInP/ZnS quantum dots because of molecular precursors depletion and growth stage continuation through Ostwald ripening process. Using fatty amines as activator along with precursors can lead to more monodispersed quantum dots. In this work, the effect of fatty amine chain length on InP/ZnS quantum dots synthesis was investigated. Octylamine, dodecylamine and oleylamine were used as the activator of InP/ZnS quantum dots synthesis. Synthesis progress and color changes in reaction mixture with time lapse, indicative of formed quantum dots concentration, was intensified in presence of fatty amines with shorter chain length. Quantum dots with smaller mean size and broader size distribution were synthesized in presence of longer fatty amines as a result of higher capping capacity of them. Thereupon the optical properties of quantum dots were affected by chain length of fatty amine. Longer wavelength of photoluminescence emission was achieved by using octylamine with the shortest chain length among selected fatty amines.

  8. Use of amine oxide surfactants for chemical flooding EOR (enhanced oil recovery)

    Energy Technology Data Exchange (ETDEWEB)

    Olsen, D.K.

    1989-11-01

    The use of amine oxides with and without alcohols as cosolvents, and in combination with other surfactants as mixed micellar formulations for enhanced oil recovery by surfactant flooding was investigated. Amine oxides are a salt-tolerant class of surfactants that produce low interfacial tension and can develop viscosity without the addition of polymers. These salt-tolerant formulations generate three-phase regions with hydrocarbons over a broad salinity range, develop moderate solubilization, and produce low interfacial tensions, however oil recovery from amine oxide-alcohol phase behavior optimized formulations was directly dependent upon the quantity of surfactant injected. The large pore volume and high concentration of surfactant required prohibits their economic use as the primary surfactant in chemical flooding EOR. Dimethylalkylamine oxides are useful as cosurfactants and viscosifiers in formulations with other surfactants for chemical flooding EOR but the use of ethoxylated and propoxylated amine oxides should be avoided due to the decomposition of these amine oxides under reservoir conditions. Phase behavior, phase inversion temperatures, and viscosity scans have been correlated with surfactant structures to provide a guide for amine oxide applications in chemical flooding. 36 refs., 5 figs., 6 tabs.

  9. Aging of triazine amine in soils demonstrated through sorption, desorption, and bioavailability measurements.

    Science.gov (United States)

    Godskesen, Berit; Holm, Peter E; Jacobsen, Ole S; Jacobsen, Carsten S

    2005-03-01

    The aging of triazine amine in soil was studied during a time course of 119 d by measuring bioavailability in terms of mineralization after inoculation of the triazine amine-degrading bacterium Rhodococcus erythropolis TA57. The bioavailability was measured in four soil samples: A-, B-, and C-horizons from an agricultural soil profile and in a peat soil. The sorption of triazine amine in the soil samples was quantified during the period of aging in terms of sorption distribution coefficients (Kd) and desorption distribution coefficients (Kd,des). Measures of bioavailability and triazine amine concentration in the nonavailable fraction showed effects of aging in the soils that were rich in organic matter. The triazine amine bioavailability declined significantly during the aging period in soils containing greater than 2% organic carbon, whereas the B- and C-horizons showed no signs of aging, in agreement with their low content of organic material. Corresponding to this, desorption decreased significantly in the A-horizon but, surprisingly, not in the peat soil. Analyses by thin-layer chromatography indicated an association of aqueous triazine amine and dissolved organic matter in the peat soil. This gives an explanation for both the significant decrease in bioavailability and the noncorresponding stability of the nonavailable (i.e., nondesorbed) fraction.

  10. Cheminformatics Modeling of Amine Solutions for Assessing their CO2 Absorption Properties.

    Science.gov (United States)

    Kuenemann, Melaine A; Fourches, Denis

    2017-03-07

    As stricter regulations on CO2 emissions are adopted worldwide, identifying efficient chemical processes to capture and recycle CO2 is of critical importance for industry. The most common process known as amine scrubbing suffers from the lack of available amine solutions capable of capturing CO2 efficiently. Tertiary amines characterized by low heats of reaction are considered good candidates but their absorption properties can significantly differ from one analogue to another despite high structural similarity. Herein, after collecting and curating experimental data from the literature, we have built a modeling set of 41 amine structures with their absorption properties. Then we analyzed their chemical composition using molecular descriptors and non-supervised clustering. Furthermore, we developed a series of quantitative structure-property relationships (QSPR) to assess amines' CO2 absorption properties from their structural characteristics. These models afforded reasonable prediction performances (e. g., Q(2)LOO =0.63 for CO2 absorption amount) even though they are solely based on 2D chemical descriptors and individual machine learning techniques (random forest and neural network). Overall, we believe the chemical analysis and the series of QSPR models presented in this proof-of-concept study represent new knowledge and innovative tools that could be very useful for screening and prioritizing hypothetical amines to be synthesized and tested experimentally for their CO2 absorption properties.

  11. Biogenic amines in table olives. Analysis by high-performance liquid chromatography.

    Science.gov (United States)

    Hornero-Méndez, D; Garrido-Fernández, A

    1994-09-01

    Biogenic amines in fermented vegetables have scarcely been studied. Available data show that in table olives and fermented cucumbers their presence is rare and any determinations made have been restricted mainly to histamine. However, some microorganisms, especially those related to spoilage, found in the fermentation brines of such products may have amino acid decarboxylase activity and give rise to biogenic amines by unusual processes. A method for the simultaneous determination of eight biogenic amines (tryptamine, beta-phenylethylamine, putrescine, cadaverine, histamine, tyramine, spermidine, and spermine) has been developed to study their occurrence in fermented vegetables in more detail. The method consists of extraction of the amines from olive paste with 5% m/v trichloracetic acid and successive transfers into water-saturated n-BuOH and 0.1 mol l-1 HCl. An aliquot of this mixture is dried and derivatized with dansyl chloride. The dansyl derivatives are then analysed by high-performance liquid chromatography. Special emphasis has been given to optimization of the n-BuOH and 0.1 mol l-1 HCl extractions and to the derivatization conditions. By applying this method to the analysis of spoilt olives, the presence of some biogenic amines has been demonstrated. Thus a new method for monitoring the presence of biogenic amines during the fermentation of olives and for detecting anomalous fermentations is envisaged.

  12. Enhanced removal of pentachlorophenol and 2,4-D from aqueous solution by an aminated biosorbent

    Energy Technology Data Exchange (ETDEWEB)

    Deng Shubo, E-mail: dengshubo@tsinghua.edu.cn [Department of Environmental Science and Engineering, Tsinghua University, Beijing 100084 (China); POPs Research Center, Tsinghua University, Beijing 100084 (China); Ma Rui; Yu Qiang; Huang Jun; Yu Gang [Department of Environmental Science and Engineering, Tsinghua University, Beijing 100084 (China); POPs Research Center, Tsinghua University, Beijing 100084 (China)

    2009-06-15

    The fungal biomasses of Penicillium chrysogenum were used as raw materials to prepare the aminated adsorbent through chemical grafting of polyethylenimine (PEI) on the biomass surface. Due to the protonation of amine groups, the PEI-modified biomass was found to possess the zero point of {zeta} potential at pH 10.2, higher than the pristine biomass at pH 3.8. The aminated biosorbent was effective in removing anionic pentachlorophenol (PCP) and 2,4-dichlorophenoxyacetic acid (2,4-D) from aqueous solution. The sorption was pH-dependent and the sorption kinetic data were well described by the pseudo-second-order model. The sorption isotherms on the aminated biosorbent conformed to the Langmuir equation, with the maximum sorption capacity of 1.23 mmol/g for PCP and 1.22 mmol/g for 2,4-D. In the presence of Cu{sup 2+} or Pb{sup 2+}, the sorption capacities for both PCP and 2,4-D were further enhanced, attributed to the formation of surface complex. FTIR and {zeta} potential analysis before and after the sorption revealed that the amine groups on the biomass surface played an important role in the sorption of PCP and 2,4-D, due to the electrostatic interaction between the positive protonated amine groups and the negative PCP/2,4-D.

  13. Mutagenic Potency of Food-Derived Heterocyclic Amines

    Energy Technology Data Exchange (ETDEWEB)

    Felton, J S; Knize, M G; Wu, R W; Colvin, M E; Hatch, F T; Malfatti, M A

    2006-10-26

    The understanding of mutagenic potency has been primarily approached using ''quantitative structure activity relationships'' (QSAR). Often this method allows the prediction of mutagenic potency of the compound based on its structure. But it does not give the underlying reason why the mutagenic activities differ. We have taken a set of heterocyclic amine structures and used molecular dynamic calculations to dock these molecules into the active site of a computational model of the cytochrome P-450 1A1 enzyme. The calculated binding strength using Boltzman distribution constants was then compared to the QSAR value (HF/6-31G* optimized structures) and the Ames/Salmonella mutagenic potency. Further understanding will only come from knowing the complete set of mutagenic determinants. These include the nitrenium ion half-life, DNA adduct half-life, efficiency of repair of the adduct, and ultimately fixation of the mutation through cellular processes. For two isomers, PhIP and 3-Me-PhIP, we showed that for the 100-fold difference in the mutagenic potency a 5-fold difference can be accounted for by differences in the P450 oxidation. The other factor of 20 is not clearly understood but is downstream from the oxidation step. The application of QSAR (chemical characteristics) to biological principles related to mutagenesis is explored in this report.

  14. Biogenic amines and hygienic quality of lucerne silage

    Directory of Open Access Journals (Sweden)

    Mlejnkova Veronika

    2016-01-01

    Full Text Available This experiment examined the influence of two different silage additives of biological (Lactococcus lactis, Lactobacillus plantarum, Enterococcus faecium, enzyme xylanase and chemical (43% formic acid, 30% ammonium formate, 10% propionic acid, 2% benzoic acid types on biogenic amines concentration, nutrient content, fermentation process, and microbiologic indicators in lucerne (Medicago sativa silage after 90 days of fermentation. The biological additive significantly (P < 0.05 increased putrescine (+51%, lactic acid (+11% and protein content (+11% in comparison with control silage. It significantly decreased cadaverine (−29%, histamine (−57%, spermidine (−15%, spermine (−55%, acetic acid (−40%, ethanol (−55%, ammonium (−25% and ash (−9%. After the chemical-additive treatment, greater amounts of histamine and tyramine were recorded. Significant decrease was observed in the concentrations of putrescine (−18%, cadaverine (−55%, spermidine (−47%, spermine (−45%, lactic acid (−16%, acetic acid (−46%, ammonium (−59%, ash (−13% and fat (−24%. Populations of bacteria associated with lactic acid fermentation, moulds, yeasts, enterobacteria and total microorganisms count were also influenced. Both biological and chemical additives can be highly recommended for producing high-quality silages meeting hygienic requirements. In lucerne silage, the chemical preservative showed a stronger effect in achieving the health safety of silage compared to the biological inoculant.

  15. Technological Factors Affecting Biogenic Amine Content in Foods: A Review

    Science.gov (United States)

    Gardini, Fausto; Özogul, Yesim; Suzzi, Giovanna; Tabanelli, Giulia; Özogul, Fatih

    2016-01-01

    Biogenic amines (BAs) are molecules, which can be present in foods and, due to their toxicity, can cause adverse effects on the consumers. BAs are generally produced by microbial decarboxylation of amino acids in food products. The most significant BAs occurring in foods are histamine, tyramine, putrescine, cadaverine, tryptamine, 2-phenylethylamine, spermine, spermidine, and agmatine. The importance of preventing the excessive accumulation of BAs in foods is related to their impact on human health and food quality. Quality criteria in connection with the presence of BAs in food and food products are necessary from a toxicological point of view. This is particularly important in fermented foods in which the massive microbial proliferation required for obtaining specific products is often relater with BAs accumulation. In this review, up-to-date information and recent discoveries about technological factors affecting BA content in foods are reviewed. Specifically, BA forming-microorganism and decarboxylation activity, genetic and metabolic organization of decarboxylases, risk associated to BAs (histamine, tyramine toxicity, and other BAs), environmental factors influencing BA formation (temperature, salt concentration, and pH). In addition, the technological factors for controlling BA production (use of starter culture, technological additives, effects of packaging, other non-thermal treatments, metabolizing BA by microorganisms, effects of pressure treatments on BA formation and antimicrobial substances) are addressed. PMID:27570519

  16. Enhanced adsorption of quaternary amine using modified activated carbon.

    Science.gov (United States)

    Prahas, Devarly; Wang, M J; Ismadji, Suryadi; Liu, J C

    2014-01-01

    This study examined different methodologies to modify activated carbon (AC) for the removal of quaternary amine, tetramethylammonium hydroxide (TMAH), from water. Commercial carbon (WAC) was treated by nitric acid oxidation (NA-WAC), silica impregnation (SM-WAC0.5), and oxygen plasma (P10-WAC), and their characteristics and adsorption capacity were compared. The Langmuir model fitted the equilibrium adsorption data well under different pH. The maximum adsorption capacity of WAC was 27.77 mg/g, while those of NA-WAC, SM-WAC 0.5, and P10-WAC were 37.46, 32.83 and 29.03 mg/g, respectively. Nitric acid oxidation was the most effective method for enhancing the adsorption capacity of TMAH. Higher pH was favorable for TMAH adsorption. Desorption study revealed that NA-WAC had no considerable reduction in performance even after five cycles of regeneration by 0.1 N hydrochloric acid. It was proposed that electrostatic interaction was the main mechanism of TMAH adsorption on activated carbon.

  17. Electrochemical characterization of platinum nanoparticles stabilized by amines

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez-Meneses, E., E-mail: esthervincent@yahoo.co [Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, CICATA-IPN Unidad Altamira, Km 14.5 Carretera Tampico-Puerto Industrial, C.P. 89600 Altamira, Tamaulipas (Mexico); Dominguez-Crespo, M.A. [Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, CICATA-IPN Unidad Altamira, Km 14.5 Carretera Tampico-Puerto Industrial, C.P. 89600 Altamira, Tamaulipas (Mexico); Montiel-Palma, V. [Centro de Investigaciones Quimicas, Universidad Autonoma del Estado de Morelos, Av. Universidad 1001, Colonia Chamilpa, C.P. 62201 Cuernavaca, Morelos (Mexico); Chavez-Herrera, V.H. [Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, CICATA-IPN Unidad Altamira, Km 14.5 Carretera Tampico-Puerto Industrial, C.P. 89600 Altamira, Tamaulipas (Mexico); Gomez, E. [Instituto de Quimica-Universidad Nacional Autonoma de Mexico, Ciudad Universitaria, C.P. 04510 Mexico, D.F. (Mexico); Hernandez-Tapia, G. [Gerencia de Catalizadores y Proceso, Instituto Mexicano del Petroleo, Eje Central Lazaro Cardenas norte 152, 07730 Mexico, D.F. (Mexico)

    2009-08-26

    In this work we present the synthesis by Chaudret approach of Pt nanoparticles stabilized by primary amine (-NH{sub 2}) compounds. Their electrochemical performance as cathodes in low temperature polymer electrolite fuel cells on the oxygen reduction reaction (ORR) is also presented. Transmission electron microscopy (TEM) images of the samples show Pt nanostructures with particle size varying from 10 to 100 nm depending on the kind of the stabilizer used during the catalyst preparation. In some cases well-dispersed isolated platinum nanoparticles were observed. The activity of the dispersed catalysts (Pt/C) with respect to the ORR was investigated using steady state polarization measurements. The kinetic parameters showed that although no significant differences between the Tafel slopes of the Pt catalysts exist, transfer coefficients and exchange current densities show higher activities when the Pt nanoparticles were stabilized by tert-butylamine (TBA). The performance with respect to the ORR of the Pt/C catalyst on vulcan carbon substrate is active and comparable to that reported in the literature for state-of-art electrocatalysts.

  18. Efficient SO2 capture by amine functionalized PEG.

    Science.gov (United States)

    Yang, Dezhong; Hou, Minqiang; Ning, Hui; Zhang, Jianling; Ma, Jun; Han, Buxing

    2013-11-07

    Polyethylene glycols (PEGs) are a class of non-toxic, non-volatile, biocompatible, and widely available polymers. In this work, we synthesized N-ethyl-N-(2-(2-(2-methoxyethoxy)ethoxy)ethyl)-2-aminoethanol (EE3AE) that combines the properties of PEG and amines, and N-decyl-N-ethyl-2-aminoethanol (DEAE). Their performances to capture SO2 were studied at different temperatures, pressures, and absorption times. The interaction between the absorbents and SO2 were characterized by NMR and FTIR techniques. It was demonstrated that both EE3AE and DEAE could absorb SO2 efficiently, and there existed chemical and physical interactions between the absorbents and SO2. In particular, the absorption capacity of EE3AE could be as high as 1.09 g SO2 per g EE3AE at 1 atm. The absorption capacity of EE3AE was much larger than that of DEAE because the ether group in the EE3AE interacted with SO2 more strongly than the alkyl group in the DEAE. The SO2 absorbed by EE3AE could be stripped out by bubbling N2 or by applying a vacuum and the EE3AE could be reused. Moreover, both absorbents exhibited a high SO2-CO2 selectivity.

  19. Protected Gold Nanoparticles with Thioethers and Amines As Surrogate Ligands

    Directory of Open Access Journals (Sweden)

    M. Rafiq H. Siddiqui

    2013-01-01

    Full Text Available Dodecyl sulfide, dodecyl amine, and hexylamine were shown to act as surrogate ligands (L via metastable gold nanoparticles. By collating analytical and spectroscopic data obtained simultaneously, empirical formula Au24L was assigned. These impurity-free nanoparticles obtained in near quantitative yields showing exceptional gold assays (up to 98%Au were prepared by a modification of the two-phase method. Replacement reactions on the Au24L showed that Au:L ratios may be increased (up to Au55:L (L= (H25C122S or decreased (Au12:L (L= H2NC12H25 and H2NC6H13 as desired. This work encompassing the role of analytical techniques used, that is, elemental analysis, variable temperature 1H NMR, FAB mass spectrometry, UV-Vis spectroscopy, thin film X-ray diffraction, and high-resolution electron microscopy (HREM has implications in the study of size control, purity, stability, and metal assays of gold nanoparticles.

  20. Adenosine Amine Congener as a Cochlear Rescue Agent

    Directory of Open Access Journals (Sweden)

    Srdjan M. Vlajkovic

    2014-01-01

    Full Text Available We have previously shown that adenosine amine congener (ADAC, a selective A1 adenosine receptor agonist, can ameliorate noise- and cisplatin-induced cochlear injury. Here we demonstrate the dose-dependent rescue effects of ADAC on noise-induced cochlear injury in a rat model and establish the time window for treatment. Methods. ADAC (25–300 μg/kg was administered intraperitoneally to Wistar rats (8–10 weeks old at intervals (6–72 hours after exposure to traumatic noise (8–16 kHz, 110 dB sound pressure level, 2 hours. Hearing sensitivity was assessed using auditory brainstem responses (ABR before and 12 days after noise exposure. Pharmacokinetic studies investigated ADAC concentrations in plasma after systemic (intravenous administration. Results. ADAC was most effective in the first 24 hours after noise exposure at doses >50 μg/kg, providing up to 21 dB protection (averaged across 8–28 kHz. Pharmacokinetic studies demonstrated a short (5 min half-life of ADAC in plasma after intravenous administration without detection of degradation products. Conclusion. Our data show that ADAC mitigates noise-induced hearing loss in a dose- and time-dependent manner, but further studies are required to establish its translation as a clinical otological treatment.

  1. Biotinylated dextran amine anterograde tracing of the canine corticospinal tract

    Institute of Scientific and Technical Information of China (English)

    Xiao Han; Guangming Lv; Huiqun Wu; Dafeng Ji; Zhou Sun; Yaofu Li; Lemin Tang

    2012-01-01

    In this study, biotinylated dextran amine (BDA) was microinjected into the left cortical motor area of the canine brain. Fluorescence microscopy results showed that a large amount of BDA-labeled pyramidal cells were visible in the left cortical motor area after injection. In the left medulla oblongata, the BDA-labeled corticospinal tract was evenly distributed, with green fluorescence that had a clear boundary with the surrounding tissue. The BDA-positive corticospinal tract entered into the right lateral funiculus of the spinal cord and descended into the posterior part of the right lateral funiculus, close to the posterior horn, from cervical to sacral segments. There was a small amount of green fluorescence in the sacral segment. The distribution of BDA labeling in the canine central nervous system was consistent with the course of the corticospinal tract. Fluorescence labeling for BDA gradually diminished with time after injection. Our findings indicate that the BDA anterograde tracing technique can be used to visualize the localization and trajectory of the corticospinal tract in the canine central nervous system.

  2. Membrane Separation of 2-Ethyl Hexyl Amine/1-Decene

    KAUST Repository

    Bawareth, Bander

    2012-12-01

    1-Decene is a valuable product in linear alpha olefins plants that is contaminated with 2-EHA (2-ethyl hexyl amine). Using organic solvent nanofiltration membranes for this separation is quite challengeable. A membrane has to be a chemically stable in this environment with reasonable and stable separation factor. This paper shows that Teflon AF 2400 and cellulose acetate produced interesting results in 1-decene/2-EHA separation. The separation factor of Teflon AF 2400 is 3 with a stable permeance of 1.1x10-2 L/(m2·h·bar). Likewise, cellulose acetate gave 2-EHA/1-decene separation factor of 2 with a lower permeance of 3.67x10-3 L/(m2·h·bar). A series of hydrophilic membranes were tested but they did not give any separation due to high degree of swelling of 2-EHA with these polymers. The large swelling causes the membrane to lose its diffusivity selectivity because of an increase in the polymer\\'s chain mobility.

  3. Synthesis, Characterization, and Pharmacological Evaluation of Selected Aromatic Amines

    Directory of Open Access Journals (Sweden)

    Hammad Ismail

    2015-01-01

    Full Text Available Aromatic amines 1-amino-4-phenoxybenzene (A-1A, 2-(4-aminophenoxy naphthalene (A-2A, and 1-(4-aminophenoxy naphthalene (A-3A were synthesized by the reduction of corresponding nitroaromatics with hydrazine monohydrate and Pd/C 5% (w/w. The newly synthesized compounds were characterized by FTIR, 1H NMR, 13C NMR, UV-visible spectrophotometer, and mass spectrometry and their biological activities were investigated along with structurally similar 4-(4-aminophenyloxy biphenyl (A-A. Results of brine shrimp cytotoxicity assay showed that almost all of the compounds had LD50 values <1 μg/mL. The compounds also showed significant antitumor activity with IC50 values ranging from 67.45 to 12.2 µgmL−1. The cytotoxicity and antitumor studies correlate the results which suggests the anticancerous nature of compounds. During the interaction study of these compounds with DNA, all of the compounds showed hyperchromic effect indicating strong interaction through binding with the grooves of DNA. Moreover, A-3A also showed decrease in λmax confirming higher propensity for DNA groove binding. In DPPH free radical scavenging assay, all the compounds showed potential antioxidant capability. The compounds were highly active in protecting DNA against hydroxyl free radicals. DNA interaction and antioxidant results back up each other indicating that these compounds have potential to be used as cancer chemopreventive agents. Additionally, one compound (A-1A showed significant antibacterial and antifungal activity as well.

  4. Influence of Dissolved Metals on N-Nitrosamine Formation under Amine-based CO2 Capture Conditions.

    Science.gov (United States)

    Wang, Zimeng; Mitch, William A

    2015-10-06

    As the prime contender for postcombustion CO2 capture technology, amine-based scrubbing has to address the concerns over the formation of potentially carcinogenic N-nitrosamine byproducts from reactions between flue gas NOx and amine solvents. This bench-scale study evaluated the influence of dissolved metals on the potential to form total N-nitrosamines in the solvent within the absorber unit and upon a pressure-cooker treatment that mimics desorber conditions. Among six transition metals tested for the benchmark solvent monoethanolamine (MEA), dissolved Cu promoted total N-nitrosamine formation in the absorber unit at concentrations permitted in drinking water, but not the desorber unit. The Cu effect increased with oxygen concentration. Variation of the amine structural characteristics (amine order, steric hindrance, -OH group substitution and alkyl chain length) indicated that Cu promotes N-nitrosamine formation from primary amines with hydroxyl or carboxyl groups (amino acids), but not from secondary amines, tertiary amines, sterically hindered primary amines, or amines without oxygenated groups. Ethylenediaminetetraacetate (EDTA) suppressed the Cu effect. The results suggested that the catalytic effect of Cu may be associated with the oxidative degradation of primary amines in the absorber unit, a process known to produce a wide spectrum of secondary amine products that are more readily nitrosatable than the pristine primary amines, and that can form stable N-nitrosamines. This study highlighted an intriguing linkage between amine degradation (operational cost) and N-nitrosamine formation (health hazards), all of which are challenges for commercial-scale CO2 capture technology.

  5. Synthesis, characterization, and application of silica supported ionic liquid as catalyst for reductive amination of cyclohexanone with formic acid and triethyl amine as hydrogen source

    Institute of Scientific and Technical Information of China (English)

    Ashif H. Tamboli; Avinash A. Chaugule; Faheem A. Sheikh; Wook-Jin Chung; Hern Kim

    2015-01-01

    A silica supported ionic liquid was synthesized and characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy, X-ray diffraction, N2 adsorption-desorption, and thermogravimetric analysis. All these techniques, especially SEM results indicated the presence of well-defined spherical particles having diameters larger than the pristine silica particles, confirming the successful immobilization of the ionic liquid. The prepared silica supported ionic liquid was used in the reductive amination of cyclohexanone under different conditions with different azeo-tropic mixtures of formic acid and triethyl amine as a hydrogen source. The catalyst showed effi-cient catalytic performance and excellent yields of N-cyclohexyl amine derivatives in the range of 58%to 84%at 30 °C. After completion of the reaction, the catalyst was easily recovered by simple filtration and reused for another five cycles without any significant impact on product yields. The obtained catalytic performance indicates that the present catalyst is green, very active, and reusable for the reductive amination of cyclohexanone.

  6. Microwave-assisted chemoselective copper-catalyzed amination of o-chloro and o-bromobenzoic acids using aromatic amines under solvent free conditions

    Institute of Scientific and Technical Information of China (English)

    Yaghoub Sarrafi; Manijeh Mohadeszadeh; Kamal Alimohammadi

    2009-01-01

    Copper-catalyzed synthesis of N-aryl anthranilic acid derivatives using effective amination of 2-chloro and 2-bromobenzoic acid under microwave irradiation is reported. Some of the advantages of this method axe high chemoselectivity, short reaction times, ease of work up procedure and elimination of the need for acid protection.

  7. Arthrobacter P 1, a Fast Growing Versatile Methylotroph with Amine Oxidase as a Key Enzyme in the Metabolism of Methylated Amines

    NARCIS (Netherlands)

    Dijken, J.P. van; Veenhuis, M.; Harder, W.

    1981-01-01

    A facultative methylotrophic bacterium was isolated from enrichment cultures containing methylamine as the sole carbon source. It was tentatively identified as an Arthrobacter species. Extracts of cells grown on methylamine or ethylamine contained high levels of amine oxidase (E.C. 1.4.3) activity.

  8. Synthesis and antibacterial activity of Schiff bases and amines derived from alkyl 2-(2-formyl-4-nitrophenoxy)alkanoates.

    Science.gov (United States)

    Goszczyńska, Agata; Kwiecień, Halina; Fijałkowski, Karol

    A series of novel Schiff bases and secondary amines were obtained in good yields, as a result of the reductive amination of alkyl 2-(2-formyl-4-nitrophenoxy)alkanoates with both aniline and 4-methoxyaniline under established mild reaction conditions. Sodium triacetoxyborohydride as well as hydrogen in the presence of palladium on carbon were used as efficient reducing agents of the Schiff bases, in both direct and stepwise reductive amination processes. The Schiff bases, amines, and amine hydrochlorides were designed as potential antibacterial agents, and structure-activity relationship could be established following in vitro assays against Gram-positive and Gram-negative bacteria. The minimal inhibitory concentration and zone of inhibition were also determined. In these tests, some of Schiff bases and secondary amine hydrochlorides showed moderate-to-good activity against Gram-positive bacteria, including S. aureus, M. luteus, and S. mutans.

  9. Synthesis and characterization of aminated perfluoro polymer electrolytes

    Science.gov (United States)

    Page-Belknap, Zachary Stephan Glenn

    Polymer electrolytes have been developed for use in anion exchange membrane fuel cells for years. However, due to the highly corrosive environment within these fuel cells, poor chemical stability of the polymers and low ion conductivity have led to high development costs and thus prevention from widespread commercialization. The work in this study aims to provide a solution to these problems through the synthesis and characterization of a novel polymer electrolyte. The 800 EW 3M PFSA sulfonyl fluoride precursor was aminated with 3-(dimethylamino)-1-propylamine to yield a functional polymer electrolyte following quaternization, referred to in this work as PFSa-PTMa. 1 M solutions of LiPF6, HCL, KOH, NaOH, CsOH, NaHCO3 and Na2CO3 were used to exchange the polymer to alternate counterion forms. Chemical structure analysis was performed using both FT and ATR infrared spectroscopy to confirm sulfonyl fluoride replacement and the absence of sulfonic acid sites. Mechanical testing of the polymer, following counterion exchange with KOH, at saturated conditions and 60 ºC exhibited a tensile strength of 13 +/- 2.0 MPa, a Young's modulus of 87 +/- 16 MPa and a degree of elongation reaching 75% +/- 9.1%, which indicated no mechanical degradation following exposure to a highly basic environment. Conductivities of the polymer in the Cl- and OH- counterion forms at saturated conditions and 90 ºC were observed at 26 +/- 8.0 mS cm-1 and 1.1 +/- 0.1 mS cm-1, respectively. OH- conductivities were slightly above those observed for CO32- and HCO 3- counterions at the same conditions, 0.63 +/- 0.18 and 0.66 +/- 0.21 mS cm-1 respectively. The ion exchange capacity (IEC) of the polymer in the Cl- counterion form was measured via titration at 0.57 meq g-1 which correlated to 11.2 +/- 0.10 water molecules per ion site when at 60ºC and 95% relative humidity. The IEC of the polymer in the OH- counterion form following titration expressed nearly negligible charge density, less than 0.01 meq

  10. [Migration of monomers and primary aromatic amines from nylon products].

    Science.gov (United States)

    Mutsuga, Motoh; Yamaguchi, Miku; Ohno, Hiroyuki; Kawamura, Yoko

    2010-01-01

    Migration of 2 kinds of monomer and 21 kinds of primary aromatic amines (PAAs) from 21 kinds of nylon products such as turners, ladles and wrap film were determined. Samples were classified as regards materials by mean of pyrolysis-GC/MS. One sample was classified as nylon 6, 15 samples as nylon 66 and three samples as nylon 6/66 copolymers, while two samples were laminate of nylon 6 with polyethylene or polypropylene. All of the nylon 66 samples contained a small amount of ε-caprolactam (CPL), which is the nylon 6 monomer. Migration levels of monomers and PAAs at 60°C for 30 min into 20% ethanol were measured by LC/MS/MS. CPL was detected at the level of 0.015-38 µg/mL from all samples, excluding one wrap film sample, and 1,6-hexamethylenediamine was detected at the level of 0.002-0.013 µg/mL from all nylon 66 samples and one nylon 6/66 sample. In addition, 0.006-4.3 µg/mL of 4,4'-diaminodiphenylmethane from three samples, 0.032-0.23 µg/mL of aniline from four samples, 0.001 µg/mL of 4-chloroaniline from two samples, and 0.002 µg/mL of 2-toluidine and 0.066 mg/mL of 1-naphthylamine from one sample each were detected. The migration levels at 95 or 121°C were about 3 and 10 times the 60°C levels, respectively.

  11. Novel multiparametric approach to elucidate the surface amine-silanization reaction profile on fluorescent silica nanoparticles.

    Science.gov (United States)

    Roy, Shibsekhar; Dixit, Chandra K; Woolley, Robert; MacCraith, Brian D; O'Kennedy, Richard; McDonagh, Colette

    2010-12-07

    This Article addresses the important issue of the characterization of surface functional groups for optical bioassay applications. We use a model system consisting of spherical dye-doped silica nanoparticles (NPs) that have been functionalized with amine groups whereby the encapsulated cyanine-based near-infrared dye fluorescence acts as a probe of the NP surface environment. This facilitates the identification of the optimum deposition parameters for the formation of a stable ordered amine monolayer and also elucidates the functionalization profile of the amine-silanization process. Specifically, we use a novel approach where the techniques of fluorescence correlation spectroscopy (FCS) and fluorescence lifetime measurement (FL) are used in conjunction with the more conventional analytical techniques of zeta potential measurement and Fourier transfer infrared spectroscopy (FTIR). The dynamics of the ordering of the amine layer in different stages of the reaction have been characterized by FTIR, FL, and FCS. The results indicate an optimum reaction time for the formation of a stable amine layer, which is optimized for further biomolecular conjugation, whereas extended reaction times lead to a disordered cross-linked layer. The results have been validated using an immunoglobulin (IgG) plate-based direct binding assay where the maximum number of IgG-conjugated aminated NPs were captured by immobilized anti-IgG antibodies for the NP sample corresponding to the optimized amine-silanization condition. Importantly, these results point to the potential of FCS and FL as useful analytical tools in diverse fields such as characterization of surface functionalization.

  12. The ozonolysis of primary aliphatic amines in single and multicomponent fine particles

    Directory of Open Access Journals (Sweden)

    J. Zahardis

    2007-10-01

    Full Text Available The oxidative processing by ozone of the particulate amines octadecylamine (ODA and hexadecylamine (HDA is reported. Ozonolysis of these amines resulted in strong NO2 and NO3 ion signals that increased with ozone exposure as monitored by photoelectron resonance capture ionization aerosol mass spectrometry. These products suggest a mechanism of progressive oxidation of the particulate amines to nitro alkanes. Additionally, a strong ion signal at 125 m/z is assigned to the ion NO3(HNO3. For ozonized mixed particles containing ODA or HDA + oleic acid (OL, with pO3≥3×10−7 atm, imine, secondary amide, and tertiary amide products were measured. These products most likely arise from reactions of amines with aldehydes (for imines and stabilized Criegee intermediates (SCI or secondary ozonides (for amides from the fatty acid. The routes to amides via SCI and/or secondary ozonides was shown to be more important than comparable amide forming reactions between amines and organic acids, using azelaic acid as a test compound. Finally, direct evidence is provided for the formation of a surface barrier in the ODA + OL reaction system that resulted in the retention of OL at high ozone exposures (up to 10−3 atm for 17 s. This effect was not observed in HDA + OL or single component OL particles, suggesting that it may be a species-specific surfactant effect from an in situ generated amide or imine. Implications to tropospheric chemistry, including particle bound amines as sources of oxidized gas phase nitrogen species (e.g. NO2, NO3, formation of nitrogen enriched HULIS via ozonolysis of amines and source apportionment are discussed.

  13. Metal Monolithic Amine-grafted Zeolite for CO{sub 2} Capture

    Energy Technology Data Exchange (ETDEWEB)

    Chuang, Steven

    2011-03-31

    The solid amine sorbent for CO{sub 2} capture process has advantages of simplicity and low operating cost compared to the MEA (monoethanolamine) process. Solid amine sorbents reported so far suffered from either low CO{sub 2} capture capacity or low stability. The solid amine sorbent developed in this project exhibited more than 3.2 mmol/g and degraded less than 10% even after 500 cycles of heating and cooling in absence of steam. The presence of steam further enhanced CO{sub 2} capture capacity. The cost of the sorbent is estimated to be less than $7.00/lb. This sorbent was developed using the results of in situ infrared spectroscopic study. Infrared results showed that CO{sub 2} adsorbs on TEPA (tetraethylenepentamine)/PEG (polyethylene glycol) as carbamates and bicarbonates. The CO{sub 2} adsorption capacity and oxidation resistance of the amine sorbent can be enhanced by the interactions between NH{sub 2} of TEPA molecules with the OH group of PEG molecules. PEG was also found to be effectively disperse and immobilize the aromatic amines for SO{sub 2} adsorption. The infrared study also showed that SiO{sub 2} is a significantly better support than zeolites due to its proper hydrophobicity. The results of this study led to the development of a high performance solid amine sorbent under simulated gas flow condition in a fixed bed, a fluidized bed, and a metal monolith unit. This study showed heat transfer could become a major technical issue in scaling up a fixed bed adsorber. The use of the fluidized bed and metal monoliths can alleviate the heat transfer issue. The metal monolith could be suitable for small scale applications due to the high cost of manufacturing; the fluidized bed mode would be most suitable for large scale applications. Preliminary economic analysis suggested that the Akron solid amine process would cost 45% less than that of MEA process.

  14. Changes in gene expression induced by aromatic amine drugs: testing the danger hypothesis.

    Science.gov (United States)

    Ng, Winnie; Uetrecht, Jack

    2013-01-01

    Virtually all drugs that contain a primary aromatic amine are associated with a high incidence of idiosyncratic drug reactions (IDRs), suggesting that this functional group has biological effects that may be used as biomarkers to predict IDR risk. Most IDRs exhibit evidence of immune involvement and the ability of aromatic amines to form reactive metabolites and redox cycle may be responsible for initiation of an immune response through induction of cell stress, as postulated by the Danger Hypothesis. If true, danger signals could be biomarkers of IDR risk. A previous attempt to test the Danger Hypothesis found that sulfamethoxazole (SMX), the only aromatic amine tested, was also the only drug not associated with an increase of cell stress genes in mice. To ensure that these observations were not species-specific, and to determine biomarkers of IDR risk common to aromatic amines, rats were treated with SMX and two other aromatic amine drugs, dapsone (DDS) and aminoglutethimide (AMG), and hepatic gene expression was determined using microarrays. As in mice, SMX induced minimal gene changes in the rat, and none indicated cell stress, whereas DDS and AMG induced several changes including up-regulation of enzymes such as aldo-keto reductase, glutathione-S-transferase, and aldehyde dehydrogenase, which may represent danger signals. Early insulin-induced hepatic gene (Eiih) was up-regulated by all three drugs. Some mRNA changes were observed in the Keap-1-Nrf2-ARE pathway; however, the pattern was significantly different for each drug. Overall, the most salient finding was that the changes in the liver were minimal, even though aromatic amines cause a high incidence of IDRs. The liver generates a large number of reactive species; however, the ability of aromatic amines to be bioactivated by cells of the immune system may be why they cause a high incidence of IDRs.

  15. Applying of copper(ІІ carbonate as a decrease mode of a fire hazard of epoxy-amine composites

    Directory of Open Access Journals (Sweden)

    Олена Іванівна Лавренюк

    2016-05-01

    Full Text Available Being based on data about electronic and crystal structure of copper salts, their using perspective for fire retardants of epoxy-amine composites have been foreseen. Epoxy-amine composites modified by copper compounds, in particular, by copper(ІІ carbonate have been elaborated. Influence of fire retardant onto processes of thermal-oxidative decomposition of epoxy-amine composites and their fire hazard has been studied

  16. Unexpected Reduction of Ethyl 3-Phenylquinoxaline-2- carboxylate 1,4-Di-N-oxide Derivatives by Amines

    Directory of Open Access Journals (Sweden)

    Antonio Monge

    2008-01-01

    Full Text Available The unexpected tendency of amines and functionalized hydrazines to reduceethyl 3-phenylquinoxaline-2-carboxylate 1,4-di-N-oxide (1 to afford a quinoxaline 1c andmono-oxide quinoxalines 1a and 1b is described. The experimental conditions werestandardized to the use of two equivalents of amine in ethanol under reflux for two hours,with the aim of studying the distinct reductive profiles of the amines and thechemoselectivity of the process. With the exception of hydrazine hydrate, which reducedcompound 1 to a 3-phenyl-2-quinoxalinecarbohydrazide derivative, the amines only actedas reducing agents.

  17. Occurrence of aromatic amines and N-nitrosamines in the different steps of a drinking water treatment plant.

    Science.gov (United States)

    Jurado-Sánchez, Beatriz; Ballesteros, Evaristo; Gallego, Mercedes

    2012-09-15

    The occurrence of 24 amines within a full scale drinking water treatment plant that used chlorinated agents as disinfectants was evaluated for the first time in this research. Prior to any treatment (raw water), aniline, 3-chloroaniline, 3,4-dichloroaniline and N-nitrosodimethylamine were detected at low levels (up to 18 ng/L) but their concentration increased ∼10 times after chloramination while 9 new amines were produced (4 aromatic amines and 5 N-nitrosamines). Within subsequent treatments, there were no significant changes in the amine levels, although the concentrations of 2-nitroaniline, N-nitrosodimethylamine and N-nitrosodiethylamine increased slightly within the distribution system. Eleven of the 24 amines studied were undetected either in the raw and in the treatment plant samples analysed. There is an important difference in the behaviour of the aromatic amines and N-nitrosamines with respect to water temperature and rainfall events. Amine concentrations were higher in winter due to low water temperatures, this effect being more noticeable for N-nitrosamines. Aromatic amines were detected at their highest concentrations (especially 3,4-dichloroaniline and 2-nitroaniline) in treated water after rainfall events. These results may be explained by the increase in the levels of amine precursors (pesticides and their degradation products) in raw water since the rainfall facilitated the transport of these compounds from soil which was previously contaminated as a result of intensive agricultural practices.

  18. Dry fermented sausages of Southern Italy: a comparison of free amino acids and biogenic amines between industrial and homemade products.

    Science.gov (United States)

    Leggio, Antonella; Belsito, Emilia L; De Marco, Rosaria; Di Gioia, Maria L; Liguori, Angelo; Siciliano, Carlo; Spinella, Mariagiovanna

    2012-04-01

    This paper compares some important parameters and the free amino acid and biogenic amine contents of cured industrial and homemade meat products. To this aim, industrial and homemade "soppressata" and "salsiccia", typical dry fermented sausages produced in Southern Italy, were analyzed. The homemade sausages showed a higher level of free biogenic amines than that manufactured industrially, most likely because biogenic amine formation in industrial products is limited by the use of starter cultures. The industrial sausages are characterized by a higher total free amino acid content than the homemade products. Overall, free amino acid and biogenic amine contents demonstrated that appreciable differences exist between homemade and industrial sausages.

  19. Important Roles of Enthalpic and Entropic Contributions to CO 2 Capture from Simulated Flue Gas and Ambient Air Using Mesoporous Silica Grafted Amines

    KAUST Repository

    Alkhabbaz, Mustafa A.

    2014-09-24

    © 2014 American Chemical Society. The measurement of isosteric heats of adsorption of silica supported amine materials in the low pressure range (0- 0.1 bar) is critical for understanding the interactions between CO2 and amine sites at low coverage and hence to the development of efficient amine adsorbents for CO2 capture from flue gas and ambient air. Heats of adsorption for an array of silica-supported amine materials are experimentally measured at low coverage using a Calvet calorimeter equipped with a customized dosing manifold. In a series of 3-aminopropylfunctionalized silica materials, higher amine densities resulted in higher isosteric heats of adsorption, clearly showing that the density/proximity of amine sites can influence the amine efficiency of adsorbents. In a series of materials with fixed amine loading but different amine types, strongly basic primary and secondary amine materials are shown to have essentially identical heats of adsorption near 90 kJ/mol. However, the adsorption uptakes vary substantially as a function of CO2 partial pressure for different primary and secondary amines, demonstrating that entropic contributions to adsorption may play a key role in adsorption at secondary amine sites, making adsorption at these sites less effi cient at the low coverages that are important to the direct capture of CO2 from ambient air. Thus, while primary amines are confirmed to be the most effective amine types for CO2 capture from ambient air, this is not due to enhanced enthalpic contributions associated with primary amines over secondary amines, but may be due to unfavorable entropic factors associated with organization of the second alkyl chain on the secondary amine during CO2 adsorption. Given this hypothesis, favorable entropic factors may be the main reason primary amine based adsorbents are more effective under air capture conditions.

  20. Important roles of enthalpic and entropic contributions to CO2 capture from simulated flue gas and ambient air using mesoporous silica grafted amines.

    Science.gov (United States)

    Alkhabbaz, Mustafa A; Bollini, Praveen; Foo, Guo Shiou; Sievers, Carsten; Jones, Christopher W

    2014-09-24

    The measurement of isosteric heats of adsorption of silica supported amine materials in the low pressure range (0-0.1 bar) is critical for understanding the interactions between CO2 and amine sites at low coverage and hence to the development of efficient amine adsorbents for CO2 capture from flue gas and ambient air. Heats of adsorption for an array of silica-supported amine materials are experimentally measured at low coverage using a Calvet calorimeter equipped with a customized dosing manifold. In a series of 3-aminopropyl-functionalized silica materials, higher amine densities resulted in higher isosteric heats of adsorption, clearly showing that the density/proximity of amine sites can influence the amine efficiency of adsorbents. In a series of materials with fixed amine loading but different amine types, strongly basic primary and secondary amine materials are shown to have essentially identical heats of adsorption near 90 kJ/mol. However, the adsorption uptakes vary substantially as a function of CO2 partial pressure for different primary and secondary amines, demonstrating that entropic contributions to adsorption may play a key role in adsorption at secondary amine sites, making adsorption at these sites less efficient at the low coverages that are important to the direct capture of CO2 from ambient air. Thus, while primary amines are confirmed to be the most effective amine types for CO2 capture from ambient air, this is not due to enhanced enthalpic contributions associated with primary amines over secondary amines, but may be due to unfavorable entropic factors associated with organization of the second alkyl chain on the secondary amine during CO2 adsorption. Given this hypothesis, favorable entropic factors may be the main reason primary amine based adsorbents are more effective under air capture conditions.

  1. Deposition of stable amine coating onto polycaprolactone nanofibers by low pressure cyclopropylamine plasma polymerization

    Energy Technology Data Exchange (ETDEWEB)

    Manakhov, Anton [Plasma Technologies, CEITEC — Central European Institute of Technology, Masaryk University, Kotlářská 2, Brno 61137 (Czech Republic); Nečas, David [Plasma Technologies, CEITEC — Central European Institute of Technology, Masaryk University, Kotlářská 2, Brno 61137 (Czech Republic); Department of Physical Electronics, Faculty of Science, Masaryk University, Kotlářská 2, Brno 61137 (Czech Republic); Čechal, Jan [CEITEC — Central European Institute of Technology, Brno University of Technology, Technická 3058/10, 616 00 Brno (Czech Republic); Pavliňák, David [Department of Physical Electronics, Faculty of Science, Masaryk University, Kotlářská 2, Brno 61137 (Czech Republic); Eliáš, Marek [Plasma Technologies, CEITEC — Central European Institute of Technology, Masaryk University, Kotlářská 2, Brno 61137 (Czech Republic); Department of Physical Electronics, Faculty of Science, Masaryk University, Kotlářská 2, Brno 61137 (Czech Republic); and others

    2015-04-30

    Amine-rich films are of high interest for the bio-applications including drug delivery and tissue engineering thanks to their high reactivity allowing the formation of the covalent linkages between biomolecules and a surface. However, the bio-applications of amine-rich films require their good stability in water which is often achieved at large expenses of the amine concentration. Recently, non-toxic cyclopropylamine (CPA) has been applied for the plasma polymerization of films bearing high NH{sub x} environment combined with the moderate thickness loss (20%) after water immersion for 48 h. In this work, the amine-rich film with the NH{sub x} concentration over 7 at.% was deposited on Si substrates and polycaprolactone nanofiber meshes by using CPA plasma polymerization (pulsed mode) in a vertically oriented stainless steel reactor. The substrates were placed at the radio frequency electrode and the ion bombardment caused by direct-current self-bias was suppressed by using high pressure of 50 Pa. Analysis of samples by scanning electron microscopy did not reveal any cracks in the deposited layer formed during a sample immersion in water. Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS) confirmed a slight oxidation of amine groups in water but the film still contained 5 at.% of NH{sub x} (according to the N1s XPS fitting) after the immersion. The rapid oxidation of amine groups was observed during the aging experiment carried out in air at room temperature because FTIR revealed an increase of amide peaks that increased progressively with aging time. However, this oxidation was significantly reduced if the plasma polymer was stored at − 20 °C. Since the films exhibit high amine concentration and very good water stability they have great potential for applications as biocompatible functional coatings. - Highlights: • Cyclopropylamine plasma polymers deposited on polycaprolactone nanofibers • Amine-rich films with high

  2. Probing Intramolecular versus Intermolecular CO2 Adsorption on Amine-Grafted SBA-15.

    Science.gov (United States)

    Yoo, Chun-Jae; Lee, Li-Chen; Jones, Christopher W

    2015-12-15

    A mesoporous silica SBA-15 is modified with an array of amine-containing organosilanes including (i) propylamine, SiCH2CH2CH2NH2 (MONO), (ii) propylethylenediamine, SiCH2CH2CH2NHCH2CH2NH2 (DI), (iii) propyldiethylenetriamine, SiCH2CH2CH2NHCH2CH2NHCH2CH2NH2 (TRI), and (iv) propyltriethylenetetramine, SiCH2CH2CH2NHCH2CH2N(CH2CH2NH2)2 (TREN) and the low loading silane adsorbents (∼0.45 mmol silane/g) are evaluated for their CO2 adsorption properties, with a focus on gaining insight into the propensity for intramolecular vs intermolecular CO2 adsorption. Adsorption isotherms at low CO2 coverages are measured while simultaneously recording the heat evolved via a Tian-Calvet calorimeter. The results are compared on a silane molecule efficiency basis (mol CO2 adsorbed/mol silane) to assess the potential for intramolecular CO2 adsorption, employing two amine groups in a single silane molecule. As the number of amines in the silane molecule increases (MONO capture CO2. Analysis of the CO2 uptake for samples with the surface silanols removed by capping demonstrates that cooperative uptake due to amine-CO2-silanol interactions is also possible over these adsorbents and is the primary mode of sorption for the MONO material at the studied low silane loading. As the propensity for intramolecular CO2 capture increases due to the presence of multiple amines in a single silane molecule (MONO amine-containing silanes at low coverage is the first to provide significant, direct evidence for intramolecular CO2 capture in a single silane molecule. Furthermore, it provides evidence for the relative heats of adsorption for physisorption on a silanol laden surface (ca. 37 kJ/mol), a silanol-capped surface (ca. 25 kJ/mol), via amine-CO2-silanol interactions (ca. 46 kJ/mol), and via amine-CO2-amine interactions at low surface coverages (ca. 65 kJ/mol).

  3. Steady-state inhibition model for the biodegradation of sulfonated amines in a packed bed reactor.

    Science.gov (United States)

    Juárez-Ramírez, Cleotilde; Galíndez-Mayer, Juvencio; Ruiz-Ordaz, Nora; Ramos-Monroy, Oswaldo; Santoyo-Tepole, Fortunata; Poggi-Varaldo, Héctor

    2015-05-25

    Aromatic amines are important industrial products having in their molecular structure one or more aromatic rings. These are used as precursors for the synthesis of dyes, adhesives, pesticides, rubber, fertilizers and surfactants. The aromatic amines are common constituents of industrial effluents, generated mostly by the degradation of azo dyes. Several of them are a threat to human health because they can by toxic, allergenic, mutagenic or carcinogenic. The most common are benzenesulfonic amines, such as 4-ABS (4-aminobenzene sulfonic acid) and naphthalene sulfonic amines, such as 4-ANS (4-amino naphthalene sulfonic acid). Sometimes, the mixtures of toxic compounds are more toxic or inhibitory than the individual compounds, even for microorganisms capable of degrading them. Therefore, the aim of this study was to evaluate the degradation of the mixture 4-ANS plus 4-ABS by a bacterial community immobilized in fragments of volcanic stone, using a packed bed continuous reactor. In this reactor, the amines loading rates were varied from 5.5 up to 69 mg L(-1) h(-1). The removal of the amines was determined by high-performance liquid chromatography and chemical oxygen demand. With this information, we have studied the substrate inhibition of the removal rate of the aromatic amines during the degradation of the mixture of sulfonated aromatic amines by the immobilized microorganisms. Experimental results were fitted to parabolic, hyperbolic and linear inhibition models. The model that best characterizes the inhibition of the specific degradation rate in the biofilm reactor was a parabolic model with values of RXM=58.15±7.95 mg (10(9) cells h)(-1), Ks=0.73±0.31 mg L(-1), Sm=89.14±5.43 mg L(-1) and the exponent m=5. From the microbial community obtained, six cultivable bacterial strains were isolated and identified by sequencing their 16S rDNA genes. The strains belong to the genera Variovorax, Pseudomonas, Bacillus, Arthrobacter, Nocardioides and Microbacterium. This

  4. Removal of aromatic amines from water by montmorillonite-(cerium or zirconium) phosphate crosslinked compounds

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez-Pradas, E.; Villafranca-Sanchez, M.; Urena-Amate, M.D. (Univ. of Almeria (Spain). Dept. of Inorganic Chemistry); Del Rey-Bueno, F.; Garcia-Rodriguez, A. (Univ. of Granada (Spain). Dept. of Inorganic Chemistry)

    To evaluate the potential use of two montmorillonite-(Ce or Zr) phosphate crosslinked compounds in removing organic pollutants such as aniline, p-toluidine, and p-acetylaniline from water, adsorption experiments were performed under conditions of varied temperature (288 and 308 K). Adsorption on the montmorillonite-Ce-phosphate compound was best described by a hyperbolic (H-type) isotherm, whereas for the montmorillonite-Zr-phosphate compound, S-type isotherms were obtained for p-toluidine and aniline and L-type for p-acetylaniline. Amines adsorption increases with increasing temperature on the cerium crosslinked material, while for the zirconium-crosslinked compound, adsorption decreases as temperature increases from 288 to 308 K, possibly due to a mainly physical process. Fourier-transform infrared (FTIR) spectroscopy indicated that at the pH generated by the adsorbents, the protonated species of these amines plays an important role in the adsorption process. X-ray diffraction analysis showed that the aromatic amines are intercalated into the adsorbents. For any given amine, the cerium-montmorillonite adsorbent shows a higher capacity of adsorption compared with zirconium-montmorillonite adsorbent, so it might be reasonably used in removing aromatic amines from water.

  5. Thermodynamics of protonation of amines in aqueous solutions at elevated temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Inna, E-mail: inna.kim@sintef.no [SINTEF Materials and Chemistry, N-7465 Trondheim (Norway); Jens, Christian M., E-mail: chrijens@stud.ntnu.no [Norwegian University of Science and Technology (NTNU), N-7491 Trondheim (Norway); Grimstvedt, Andreas, E-mail: andreas.grimstvedt@sintef.no [SINTEF Materials and Chemistry, N-7465 Trondheim (Norway); Svendsen, Hallvard F., E-mail: hallvard.svendsen@chemeng.ntnu.no [Norwegian University of Science and Technology (NTNU), N-7491 Trondheim (Norway)

    2011-11-15

    Highlights: > Effect of ionic strength and temperature on dissociation constants of amines. > Effect of ionic strength of temperature on enthalpies of protonation of amines. > Measured dissociation constants and enthalpies of protonation used for fitting. > Coefficients for thermodynamically consistent correlations given for 5 amines. - Abstract: The dissociation constants, pK{sub a}, of monoethanolamine (MEA), N-methyldiethanolamine (MDEA), 2-amino-2-methyl-1-propanol (AMP), 2(2-aminoethyl)etanolamine (AEEA), and piperazine (Pz) were measured by potentiometric titration over the temperature range (298.15 to 363.15) K. Enthalpies of protonation, {Delta}H{sub p}, were measured calorimetrically at temperatures from (298.15 to 393.15) K for MEA, MDEA, and AMP, and from (298.15 to 353.15) K for AEEA and Pz. In addition, the effect of the ionic strength of the solutions on the protonation of MDEA was studied using NaCl as background salt {l_brace}(0 to 5.5) mol/kg-H{sub 2}O){r_brace}. Correlations for the reaction equilibrium constants for proton dissociation are proposed for the studied amines based on the experimental data from literature and from this work. Both experimental enthalpy data and dissociation constants were used for fitting. The results from this work may be used for thermodynamic modeling of CO{sub 2} capture processes using amines.

  6. Safety assessment of the biogenic amines in fermented soya beans and fermented bean curd.

    Science.gov (United States)

    Yang, Juan; Ding, Xiaowen; Qin, Yingrui; Zeng, Yitao

    2014-08-06

    To evaluate the safety of biogenic amines, high performance liquid chromatography (HPLC) was used to evaluate the levels of biogenic amines in fermented soya beans and fermented bean curd. In fermented soya beans, the total biogenic amines content was in a relatively safe range in many samples, although the concentration of histamine, tyramine, and β-phenethylamine was high enough in some samples to cause a possible safety threat, and 8 of the 30 samples were deemed unsafe. In fermented bean curd, the total biogenic amines content was more than 900 mg/kg in 19 white sufu amples, a level that has been determined to pose a safety hazard; putrescine was the only one detected in all samples and also had the highest concentration, which made samples a safety hazard; the content of tryptamine, β-phenethylamine, tyramine, and histamine had reached the level of threat to human health in some white and green sufu samples, and that may imply another potential safety risk; and 25 of the 33 samples were unsafe. In conclusion, the content of biogenic amines in all fermented soya bean products should be studied and appropriate limits determined to ensure the safety of eating these foods.

  7. Bifunctional (cyclopentadienone)iron-tricarbonyl complexes: Synthesis, computational studies and application in reductive amination

    KAUST Repository

    Moulin, Solenne

    2013-11-15

    Reductive amination under hydrogen pressure is a valuable process in organic chemistry to access amine derivatives from aldehydes or ketones. Knölker\\'s complex has been shown to be an efficient iron catalyst in this reaction. To determine the influence of the substituents on the cyclopentadienone ancillary ligand, a series of modified Knölker\\'s complexes was synthesised and fully characterised. These complexes were also transformed into their analogous acetonitrile iron-dicarbonyl complexes. Catalytic activities of these complexes were evaluated and compared in a model reaction. The scope of this reaction is also reported. For mechanistic insights, deuterium-labelling experiments and DFT calculations were undertaken and are also presented. Festival of amination: Two series of modified Knölker\\'s complexes were synthesised and applied in the reductive amination of various carbonyl derivatives with primary or secondary amines (see scheme, TIPS = triisopropylsilyl). For a mechanistic insight, deuterium-labelling experiments and DFT calculations were undertaken and are also presented. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Advanced Development and Characterization of DEA Amine-Polysulfone/Polyvinylacetate Blend Membranes

    Directory of Open Access Journals (Sweden)

    Asim Mushtaq

    2014-09-01

    Full Text Available Membrane technology effectively separates CO2 from CH4 and has been practiced for many years but requires membranes with high selectivity and permeability. Different approaches are employed to improve membrane performance and it is soon possible to develop a blended polymeric membrane that separates high pressure gas streams at the point of processing pressure. However, glassy polymers suffer a lack of permeability causing their performance to drop as an upper bound trade-off but highly selective and rubbery polymers have high permeability with low selectivity. As an amine solution is capable of purifying naturally acidic gas, blending glassy, rubbery polymers with amines-specifically, polysulfone and polyvinyl acetate with diethanol amine in dimethyl acetamide as solvent-we developed flat sheet membranes with desirable properties. As it is now possible to acquire amine-polymer blends with more desirable properties by mixing with a miscible polymer, it is essential to observe factors that affect the polymer's miscibility with amines. Hence, we also analyzed the effects of blend ratios on different properties. Blended membranes of different ratios were synthesized and their functional groups were characterized by Fourier Transformed Infra-Red spectroscopy (FTIR. We then employed Thermal Gravimetric Analysis (TGA to describe weight loss and Field Emission Scanning Electron Microscopy (FESEM to determine respective morphologies.

  9. Hydroxypyridyl Imines: Enhancing Chromatographic Separation and Stereochemical Analysis of Chiral Amines via Circular Dichroism.

    Science.gov (United States)

    Joyce, Leo A; Regalado, Erik L; Welch, Christopher J

    2016-09-16

    Imine-bond formation between chiral amines and commercially available 3-hydroxypyridine-2-carboxaldehyde (HCA) was exploited for rapid determination of stereochemical composition. Chiral supercritical fluid chromatography (SFC) screening of the derivatized imine compounds led to the elucidation of multiple combinations of mobile and stationary phases that gave resolution of all members of a series of chiral amines. The first eluting enantiomer was generally the derivative of the (R)-amine enantiomer across the series that was studied, indicating that the imine formed from the (S)-amine has more favorable interaction with the chiral stationary phase of the column. These conditions were then applied to more challenging compounds, namely amino alcohols and diastereomers possessing more than one stereocenter. The approach was utilized to monitor stereoselective biocatalytic transamination and assign the absolute configuration of the enantiomeric products. Finally, hydrolysis of the imine bond of the derivative was shown to generate enantiopure amine starting materials without racemization. This further highlights the value of this approach for creating readily reversed derivatives that enhance chromatographic separation and aid in the determination of absolute configuration.

  10. Cocaine affects foraging behaviour and biogenic amine modulated behavioural reflexes in honey bees

    Directory of Open Access Journals (Sweden)

    Eirik Søvik

    2014-11-01

    Full Text Available In humans and other mammals, drugs of abuse alter the function of biogenic amine pathways in the brain leading to the subjective experience of reward and euphoria. Biogenic amine pathways are involved in reward processing across diverse animal phyla, however whether cocaine acts on these neurochemical pathways to cause similar rewarding behavioural effects in animal phyla other than mammals is unclear. Previously, it has been shown that bees are more likely to dance (a signal of perceived reward when returning from a sucrose feeder after cocaine treatment. Here we examined more broadly whether cocaine altered reward-related behaviour, and biogenic amine modulated behavioural responses in bees. Bees developed a preference for locations at which they received cocaine, and when foraging at low quality sucrose feeders increase their foraging rate in response to cocaine treatment. Cocaine also increased reflexive proboscis extension to sucrose, and sting extension to electric shock. Both of these simple reflexes are modulated by biogenic amines. This shows that systemic cocaine treatment alters behavioural responses that are modulated by biogenic amines in insects. Since insect reward responses involve both octopamine and dopamine signalling, we conclude that cocaine treatment altered diverse reward-related aspects of behaviour in bees. We discuss the implications of these results for understanding the ecology of cocaine as a plant defence compound. Our findings further validate the honey bee as a model system for understanding the behavioural impacts of cocaine, and potentially other drugs of abuse.

  11. The kinetics and mechanism of the organo-iridium catalysed racemisation of amines.

    Science.gov (United States)

    Stirling, Matthew J; Mwansa, Joseph M; Sweeney, Gemma; Blacker, A John; Page, Michael I

    2016-08-07

    The dimeric iodo-iridium complex [IrCp*I2]2 (Cp* = pentamethylcyclopentadiene) is an efficient catalyst for the racemisation of secondary and tertiary amines at ambient and higher temperatures with a low catalyst loading. The racemisation occurs with pseudo-first-order kinetics and the corresponding four rate constants were obtained by monitoring the time dependence of the concentrations of the (R) and (S) enantiomers starting with either pure (R) or (S) and show a first-order dependence on catalyst concentration. Low temperature (1)H NMR data is consistent with the formation of a 1 : 1 complex with the amine coordinated to the iridium and with both iodide anions still bound to the metal-ion, but at the higher temperatures used for kinetic studies binding is weak and so no saturation zero-order kinetics are observed. A cross-over experiment with isotopically labelled amines demonstrates the intermediate formation of an imine which can dissociate from the iridium complex. Replacing the iodides in the catalyst by other ligands or having an amide substituent in Cp* results in a much less effective catalysts for the racemisation of amines. The rate constants for a deuterated amine yield a significant primary kinetic isotope effect kH/kD = 3.24 indicating that hydride transfer is involved in the rate-limiting step.

  12. Granulation in amine-storage organelles of mouse megakaryocytes: X-ray microprobe analysis and radioautography.

    Science.gov (United States)

    Daimon, T; Kawai, K; Uchida, K

    1995-02-01

    The mechanisms and the processes of the storage of bivalent cations, ATP and 5-hydroxytryptamine (5HT) in the precursors of the amine-storage organelles of megakaryocytes were studied at the electron microscopic level. Although the precursors of the amine-storage organelles in the megakaryocytes fixed with glutaraldehyde and osmium tetroxide were empty, the electron opaque granules were observed in these organelles of the freeze-substituted megakaryocytes cut onto ethylene glycol. X-ray microprobe analysis demonstrated that they contained P, Mg and Ca. Quantitative differences in bivalent cations in the granules were not observed between megakaryocytes and blood platelets. Electron opaque uranaffin-reaction products were observed in the precursors of the amine-storage organelles of the megakaryocytes after treatment with the uranaffin reaction for ATP. However, few chromaffin positive granules were observed in the precursors of the amine-storage organelles after the chromaffin reaction for monoamines. Radioautographic analysis demonstrated that blood platelets avidly took up 3H-5HT but megakaryocytes were not able to accumulate 3H-5HT in vivo. These results indicate that megakaryocytes do not yet acquire the well developed uptake system of 5HT in vivo, while they readily accumulate cations and ATP in the precursors of the amine-storage organelles.

  13. BIOGENIC AMINES CONTENT IN SELECTED COMMERCIAL FERMENTED PRODUCTS OF ANIMAL ORIGIN

    Directory of Open Access Journals (Sweden)

    Vendula Pachlová

    2012-08-01

    Full Text Available The aim of this study was to monitor of biogenic amines contents in commercial fermented products, especially various type of ripening cheeses and fermented meat products (15 cheese samples and nine dry fermented meat products obtained from Czech Republic, Slovak Republic, Poland, and Germany. Furthermore, the changes in samples during storage were also observed. The samples were stored at 6±1°C. The samples were taken the first day of storage and the last day of shelf-life. The biogenic amines content was determined using ion-exchange liquid chromatography with post-column derivatization and photometric detection. The content of biogenic amines increased during storage. The highest biogenic amines content at the end of storage was observed in Dutch-type cheeses and in Smear cheeses, in both the concentrations exceeded 1 000 mg.kg-1. Latter mentioned amount may have serious negative impact on consumer health. The lowest concentration of biogenic amines was detected in Blue cheese.

  14. Adsorption of formaldehyde vapor by amine-functionalized mesoporous silica materials

    Institute of Scientific and Technical Information of China (English)

    SRISUDA Saeung; VIROTE Boonamnuayvitaya

    2008-01-01

    The amine-functionalized mesoporous silica materials were prepared via the co-condensation reaction of tetraethoxysilane and three types of organoalkoxysilanes:3-aminopropyl-trimethoxysilane,n-(2-aminoethyl)-3-aminopropyltrimethoxysilane,and 3-(2-(2-aminoehtylamino)ethylamino) propyl-trimethoxysilane.Cetyltrimethylammonium bromide was used as a template for forming pores.Specific surface area and pore volume of the amine-functionalized mesoporous silica materials were determined using surface area and pore size analyzer.Fourier transform infrared (FTIR) spectroscope was employed for identifying the functional groups on pore surface.In addition,the amine-functionalized mesoporous silica materials were applied as adsorbents for adsorbing formaldehyde vapor.FTIR spectra showed the evidence of the reaction between formaldehyde molecules and amine groups on pore surface of adsorbents.The equilibrium data of formaldehyde adsorbed on the adsorbents were analyzed using the Langmuir,Freundiich and Temkin isotherm.The sample functionalized from n-(2-aminoethyl)-3-aminopropyltrimethoxysilane showed the highest adsorption capacity owing to its amine groups and the large pore diameter.

  15. Preparation of amine group-containing chelating fiber for thorough removal of mercury ions.

    Science.gov (United States)

    Ma, Nianfang; Yang, Ying; Chen, Shuixia; Zhang, Qikun

    2009-11-15

    An aminated chelating fiber (AF) with high adsorption capacity for mercury ions was prepared by grafting copolymerization of acrylonitrile onto polypropylene fiber, followed by aminating with chelating molecule diethylenetriamine. Effects of reaction conditions such as temperature, reaction time, bath ratio and dosage of catalyst on the grafting yield were studied. Chemical structure, tensile strength and thermal stability of AF were characterized. The adsorption performances for mercury were evaluated by batch adsorption experiments and kinetic experiments. The results show that AF is effective for the removal of mercury over a wide range of pH. The chelating fiber also shows much higher adsorption capacities for mercury, the equilibrium adsorption amount could be as high as 657.9 mg/g for mercury. The high adsorption capacity of Hg(2+) on AF is resulted from the strong chelating interaction between amine groups and mercury ions. Two amine groups coordinate with one mercury ion could be speculated from the adsorption capacity and amine group content on AF. The kinetic adsorption results indicate that the adsorption rates of AF for mercury are very rapid. Furthermore, the residual concentration was less than 1 microg/L with feed concentration of mercury below 1mg/L, which can meet the criterion of drinking water, which indicates that the chelating fiber prepared in this study could be applied to low-level Hg contaminated drinking water purification.

  16. Melatonin is formed during winemaking at safe levels of biogenic amines.

    Science.gov (United States)

    Rodriguez-Naranjo, M Isabel; Ordóñez, José L; Callejón, Raquel M; Cantos-Villar, Emma; Garcia-Parrilla, M Carmen

    2013-07-01

    The European Food Safety Authority (EFSA) has accepted health claims for the food constituent melatonin because scientific evidence shows that it is effective at reducing sleep onset latency, and that it alleviates subjective feelings of jet lag. According to risk assessment data published by EFSA in 2011, histamine and tyramine are the most toxic biogenic amines and the ones that most affect food safety. The potential formation of biogenic amines is a concern in fermented foods because of the intense microbial activity. Conversely, Saccharomyces cerevisiase produces melatonin during fermentation in the winemaking process. This study aims to evaluate the production of potentially healthy melatonin and toxic biogenic amines during the winemaking process. To this end, 11 biogenic amines (agmatine, cadaverine, histamine, methylamine, 2-phenylethylamine, putrescine, spermidine, spermine, tyramine, tryptamine and melatonin) have been monitored during the making of 5 monovarietal wines (Merlot, Palomino Fino, Syrah, Tempranillo and Tintilla de Rota). This paper shows that alcoholic and malolactic fermentation plays a crucial role in the formation of these compounds. Bioactive melatonin is formed at safe levels of the other biogenic amines.

  17. Biogenic amines determination in some traditional cheeses in West Azerbaijan province of Iran

    Directory of Open Access Journals (Sweden)

    Seyed Mehdi Razavi Rohani

    2013-06-01

    Full Text Available Biogenic amines (BA are nitrogenous compounds that possess biological activity. The source of production is the microbial decarboxylation of amino acids. This compounds are found in various types of cheese. The aim of this work was to evaluate the BA content of some traditional cheeses in West Azerbaijan province Iran. For this purpose, 70 samples of Koopeh, 10 samples of Lighvan and 5 samples of Red Salmas cheeses were obtained from local supermarkets of different cities of West Azerbaijan province. After preparation of samples, biogenic amines content was evaluated by modified HPLC method. The presence of histamine, cadaverine, putrescine and tyramine in tested cheeses were observed. Total amount of biogenic amines was highest in Red Salmas cheese with 1426.91 ppm. It followed by Lighvan cheese and Koopeh cheese with 1008.98 and 517.71 ppm, respectively. Putrescine, cadaverine, histamine and tyramine were detected in Koopeh cheese at levels up to 156.09, 282.34, 70.80, 8.48 ppm respectively. These amines were detected also in Lighvan cheese at levels up to 277.53, 342.74, 37.58, 351.12 ppm and in Red Salmas cheese samples at levels up to 438.03, 701.05, 105.21, 182.62 ppm, respectively. Large amounts of biogenic amines can indicate non hygienic conditions and contamination of used milk for cheese production.

  18. Inhibitory Effects of Spices on Biogenic Amine Accumulation during Fish Sauce Fermentation.

    Science.gov (United States)

    Zhou, Xuxia; Qiu, Mengting; Zhao, Dandan; Lu, Fei; Ding, Yuting

    2016-04-01

    The presence of high levels of biogenic amines is detrimental to the quality and safety of fish sauce. This study investigated the effects of ethanol extracts of spices, including garlic, ginger, cinnamon, and star anise extracts, in reducing the accumulation of biogenic amines during fish sauce fermentation. The concentrations of biogenic amines, which include histamine, putrescine, tyramine, and spermidine, all increased during fish sauce fermentation. When compared with the samples without spices, the garlic and star anise extracts significantly reduced these increases. The greatest inhibitory effect was observed for the garlic ethanolic extracts. When compared with controls, the histamine, putrescine, tyramine, and spermidine contents and the overall biogenic amine levels of the garlic extract-treated samples were reduced by 30.49%, 17.65%, 26.03%, 37.20%, and 27.17%, respectively. The garlic, cinnamon, and star anise extracts showed significant inhibitory effects on aerobic bacteria counts. Furthermore, the garlic and star anise extracts showed antimicrobial activity against amine producers. These findings may be helpful for enhancing the safety of fish sauce.

  19. Biogenic amines in fish: roles in intoxication, spoilage, and nitrosamine formation--a review.

    Science.gov (United States)

    Al Bulushi, Ismail; Poole, Susan; Deeth, Hilton C; Dykes, Gary A

    2009-04-01

    Biogenic amines are non-volatile amines formed by decarboxylation of amino acids. Although many biogenic amines have been found in fish, only histamine, cadaverine, and putrescine have been found to be significant in fish safety and quality determination. Despite a widely reported association between histamine and scombroid food poisoning, histamine alone appears to be insufficient to cause food toxicity. Putrescine and cadaverine have been suggested to potentiate histamine toxicity. With respect to spoilage on the other hand, only cadaverine has been found to be a useful index of the initial stage of fish decomposition. The relationship between biogenic amines, sensory evaluation, and trimethylamine during spoilage are influenced by bacterial composition and free amino acid content. A mesophilic bacterial count of log 6-7 cfu/g has been found to be associated with 5 mg histamine/100 g fish, the Food and Drug Administration (FDA) maximum allowable histamine level. In vitro studies have shown the involvement of cadaverine and putrescine in the formation of nitrosamines, nitrosopiperidine (NPIP), and nitrosopyrrolidine (NPYR), respectively. In addition, impure salt, high temperature, and low pH enhance nitrosamine formation, whereas pure sodium chloride inhibits their formation. Understanding the relationships between biogenic amines and their involvement in the formation of nitrosamines could explain the mechanism of scombroid poisoning and assure the safety of many fish products.

  20. Amines immobilized double-walled silica nanotubes for CO2 capture.

    Science.gov (United States)

    Ko, Young Gun; Lee, Hyun Jeong; Oh, Hyun Chul; Choi, Ung Su

    2013-04-15

    Novel silica support has been required for high amine loading and good CO2 molecule diffusion into its pores to increase the performance of CO2 adsorbents. Herein, amine groups supported on double-walled silica nanotubes (DWSNTs) have been prepared via the immobilization of various aminosilanes (primary, secondary, tertiary, di-, and tri-aminosilanes) on DWSNT, and found to be a very effective adsorbent for CO2 capture. Amine groups immobilized DWSNTs captured CO2 reversibly in a temperature swing process at various adsorption temperatures (25°C, 50°C, 75°C, and 100°C). The amines on modified DWSNTs showed high CO2 capture capacity in the order of tri-, di-, primary, secondary, and tertiary amines. The CO2 capture capacity of all aminosilanes immobilized DWSNTs decreased linearly with the increase of the adsorption temperature. We expect that DWSNT would be able to inspire researchers to use it not only as a support for CO2 capture but also as a promising candidate for various applications.

  1. Alkyl amine and vegetable oil mixture-a viable candidate for CO2 capture and utilization.

    Science.gov (United States)

    Uma Maheswari, A; Palanivelu, K

    2017-02-01

    In this present work, the absorption of CO2 in alkyl amines and vegetable oil mixture has been evaluated. The results showed that the absorption is higher in alkyl amines and vegetable oil mixture compared with the aqueous alkyl amines. In addition to that, by employing the greener and non-toxic vegetable oil media, the CO2 gas has been captured as well as converted into value-added products, such as carbamates of ethylenediamine, diethylenetriamine, and triethylenetetramine. The carbamates have been isolated and characterized by Fourier transform infrared and (1)H and (13)C nuclear magnetic resonance spectroscopic techniques. The formation of these products in precipitate form has not been observed in the case of aqueous medium. Among the various alkyl amine and vegetable oil combinations, triethylenetetramine in coconut oil medium showed the maximum CO2 capture capacity of 72%. The coconut oil used for the process has been recovered, recycled, and reused for 3 cycles. Thus, this novel scheme seems to be a better alternative to conquer the drawback of aqueous amine-based CO2 capture as well as for the capture and utilization of the CO2 gas to gain the value-added products.

  2. Amine functionalized graphene oxide/CNT nanocomposite for ultrasensitive electrochemical detection of trinitrotoluene.

    Science.gov (United States)

    Sablok, Kavita; Bhalla, Vijayender; Sharma, Priyanka; Kaushal, Roohi; Chaudhary, Shilpa; Suri, C Raman

    2013-03-15

    Binding of electron-deficient trinitrotoluene (TNT) to the electron rich amine groups on a substrate form specific charge-transfer Jackson-Meisenheimer (JM) complex. In the present work, we report formation of specific JM complex on amine functionalized reduced graphene oxide/carbon nanotubes- (a-rGO/CNT) nanocomposite leading to sensitive detection of TNT. The CNT were dispersed using graphene oxide that provides excellent dispersion by attaching to CNT through its hydrophobic domains and solubilizes through the available OH and COOH groups on screen printed electrode (SPE). The GO was reduced electrochemically to form reduced graphene that remarkably increases electrochemical properties owing to the intercalation of high aspect CNT on graphene flakes as shown by TEM micrograph. The surface amine functionalization of dropcasted and rGO/CNT was carried out using a bi-functional cross linker ethylenediamine. The extent of amine functionalization on modified electrodes was confirmed using energy dispersive X-ray (EDX), X-ray photoelectron spectroscopy (XPS) and confocal microscopy. The FTIR and Raman spectra further suggested the formation of JM complex between amine functionalized electrodes and TNT leading to a shift in peak intensity together with peak broadening. The a-rGO/CNT nanocomposite prepared electrode surface leads to ultra-trace detection of TNT upto 0.01 ppb with good reproducibility (n=3). The a-rGO/CNT sensing platform could be an alternate for sensitive detection of TNT explosive for various security and environmental applications.

  3. Recent trends in the determination of biogenic amines in fermented beverages - A review.

    Science.gov (United States)

    Ordóñez, José Luis; Troncoso, Ana Maria; García-Parrilla, Maria Del Carmen; Callejón, Raquel Maria

    2016-10-05

    Biogenic amines (BA) are generally considered as a food hazard, even though there is not a threshold for these biomolecules in the European legislation, except for histamine in fishery products. These compounds are formed during the storage and processing of certain foods through microbiological activity, and when present in high concentrations, could have toxicological effects, causing health problems in consumers, especially to sensitive persons. This fact, in addition to the economical concern involved, makes it necessary to control the amounts of biogenic amines in foods. For all these reasons, literature on biogenic amines in different food products, especially in fermented beverages, is extensive. This review provides an overview of the most recent trends in the determination of biogenic amines in fermented beverages focusing on novelty, improvement and optimization of analytical methods. Hence, the different sample treatment procedures (including derivatization), the most important analytical techniques and the most frequent applications are described and discussed. Although biogenic amines have been determined in wine and other fermented beverages for decades, new advancements and technical possibilities have allowed to increase the accuracy and sensitivity of analytical methods, in order to overcome the challenges posed by the complex matrices and their high intrinsic variability. Thus, the different purposes of BA determination (food safety, production process or food microbiology research) and the most widely employed analytical techniques have been reviewed.

  4. Adsorption of formaldehyde vapor by amine-functionalized mesoporous silica materials.

    Science.gov (United States)

    Srisuda, Saeung; Virote, Boonamnuayvitaya

    2008-01-01

    The amine-functionalized mesoporous silica materials were prepared via the co-condensation reaction of tetraethoxysilane and three types of organoalkoxysilanes: 3-aminopropyl-trimethoxysilane, n-(2-aminoethyl)-3-aminopropyltrimethoxysilane, and 3-(2-(2-aminoehtylamino)ethylamino) propyl-trimethoxysilane. Cetyltrimethylammonium bromide was used as a template for forming pores. Specific surface area and pore volume of the amine-functionalized mesoporous silica materials were determined using surface area and pore size analyzer. Fourier transform infrared (FTIR) spectroscope was employed for identifying the functional groups on pore surface. In addition, the amine-functionalized mesoporous silica materials were applied as adsorbents for adsorbing formaldehyde vapor. FTIR spectra showed the evidence of the reaction between formaldehyde molecules and amine groups on pore surface of adsorbents. The equilibrium data of formaldehyde adsorbed on the adsorbents were analyzed using the Langmuir, Freundlich and Temkin isotherm. The sample functionalized from n-(2-aminoethyl)-3-aminopropyltrimethoxysilane showed the highest adsorption capacity owing to its amine groups and the large pore diameter.

  5. Biogenic amine – surfactant interactions at the air-water interface.

    Science.gov (United States)

    Penfold, J; Thomas, R K; Li, P X

    2015-07-01

    The strong interaction between polyamines and anionic surfactants results in pronounced adsorption at the air-water interface and can lead to the formation of layered surface structures. The transition from monolayer adsorption to more complex surface structures depends upon solution pH, and the structure and molecular weight of the polyamine. The effects of manipulating the polyamine molecular weight and structure on the adsorption of the anionic surfactant sodium dodecyl sulphate at the air-water interface are investigated using neutron reflectivity and surface tension, for the biogenic amines putrescine, spermidine and spermine. The results show how changing the number of amine groups and the spacing between the amine groups impacts upon the surface adsorption. At lower pH, 3-7, and for the higher molecular weight polyamines, spermidine and spermine, ordered multilayer structures are observed. For putrescine at all pH and for spermidine and spermine at high pH, monolayer adsorption with enhanced surfactant adsorption compared to the pure surfactant is observed. The data for the biogenic amines, when compared with similar data for the polyamines ethylenediamine, diethylenetriamine and triethylenetetramine, indicate that the spacing between amines groups is more optimal for the formation of ordered surface multilayer structures.

  6. Tertiary-amine-containing thermo- and pH-sensitive hydrophilic ABA triblock copolymers: effect of different tertiary amines on thermally induced sol-gel transitions.

    Science.gov (United States)

    Henn, Daniel M; Wright, Roger A E; Woodcock, Jeremiah W; Hu, Bin; Zhao, Bin

    2014-03-11

    This Article reports on the synthesis of a series of well-defined, tertiary-amine-containing ABA triblock copolymers, composed of a poly(ethylene oxide) (PEO) central block and thermo- and pH-sensitive outer blocks, and the study of the effect of different tertiary amines on thermally induced sol-gel transition temperatures (T(sol-gel)) of their 10 wt % aqueous solutions. The doubly responsive ABA triblock copolymers were prepared from a difunctional PEO macroinitiator by atom transfer radical polymerization of methoxydi(ethylene glycol) methacrylate and ethoxydi(ethylene glycol) methacrylate at a feed molar ratio of 30:70 with ∼5 mol % of either N,N-diethylaminoethyl methacrylate (DEAEMA), N,N-diisopropylaminoethyl methacrylate, or N,N-di(n-butyl)aminoethyl methacrylate. The chain lengths of thermosensitive outer blocks and the molar contents of tertiary amines were very similar for all copolymers. Using rheological measurements, we determined the pH dependences of T(sol-gel) of 10 wt % aqueous solutions of these copolymers in a phosphate buffer. The T(sol-gel) versus pH curves of all polymers exhibited a sigmoidal shape. The T(sol-gel) increased with decreasing pH; the changes were small on both high and low pH sides. At a specific pH, the T(sol-gel) decreased with increasing the hydrophobicity of the tertiary amine, and upon decreasing pH the onset pH value for the T(sol-gel) to begin to increase noticeably was lower for the more hydrophobic tertiary amine-containing copolymer. In addition, we studied the effect of different tertiary amines on the release behavior of FITC-dextran from 10 wt % micellar gels in an acidic medium at 37 and 27 °C. The release profiles for three studied hydrogels at 37 °C were essentially the same, suggesting that the release was dominated by the diffusion of FITC-dextran. At 27 °C, the release was significantly faster for the DEAEMA-containing copolymer, indicating that both diffusion and gel dissolution contributed to the

  7. Electrochemical oxidation of aliphatic amines and their attachment to carbon and metal surfaces.

    Science.gov (United States)

    Adenier, Alain; Chehimi, Mohamed M; Gallardo, Iluminada; Pinson, Jean; Vilà, Neus

    2004-09-14

    The electrochemical oxidation of aliphatic amines (primary, secondary, and tertiary) has been investigated by cyclic voltammetry and preparative electrolysis. The oxidation mechanisms have been established, and the lifetimes of the radical cations have been measured for secondary and tertiary amines. These results have been put in parallel with the attachment of amines to glassy carbon, Au, and Pt electrodes by cyclic voltammetry, X-ray photoelectron spectroscopy (XPS), and infrared reflection-absorption spectroscopy (IRRAS). It is then possible to show that it is not the radical cation but the radical obtained after the deprotonation which reacts with the electrode surface. XPS results also point to the existence of a covalent bond between Au or Pt and the organic moiety.

  8. Highly efficient heterogeneous procedure for the conjugate addition of amines to electron deficient alkenes

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The novel efficient procedure has been developed for the conjugate addition of amines to electron deficient alkenes. K2CO3 supported on different carriers have been synthesized for the conjugate addition of amines and alkenes. After optimizing the reaction conditions, K2CO3/MgO was chosen as the most efficient catalyst for the reactions. The results showed that the catalyst was very efficient for the conjugate addition of amines to electron deficient alkenes with the excellent yields in several minutes. Operational simplicity, without need of any solvent, low cost of the catalyst used, high yields, reusability, excellent chemoselectivity, and applicability to large-scale reactions are the key features of this methodology.

  9. Regenerable sorbent technique for capturing CO.sub.2 using immobilized amine sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Pennline, Henry W; Hoffman, James S; Gray, McMahan L; Fauth, Daniel J; Resnik, Kevin P

    2013-08-06

    The disclosure provides a CO.sub.2 absorption method using an amine-based solid sorbent for the removal of carbon dioxide from a gas stream. The method disclosed mitigates the impact of water loading on regeneration by utilizing a conditioner following the steam regeneration process, providing for a water loading on the amine-based solid sorbent following CO.sub.2 absorption substantially equivalent to the moisture loading of the regeneration process. This assists in optimizing the CO.sub.2 removal capacity of the amine-based solid sorbent for a given absorption and regeneration reactor size. Management of the water loading in this manner allows regeneration reactor operation with significant mitigation of energy losses incurred by the necessary desorption of adsorbed water.

  10. Amide Synthesis from Alcohols and Amines Catalyzed by Ruthenium N-Heterocyclic Carbene Complexes

    DEFF Research Database (Denmark)

    Dam, Johan Hygum; Osztrovszky, Gyorgyi; Nordstrøm, Lars Ulrik Rubæk

    2010-01-01

    The direct synthesis of amides from alcohols and amines is described with the simultaneous liberation of dihydrogen. The reaction does not require any stoichiometric additives or hydrogen acceptors and is catalyzed by ruthenium N-heterocyclic carbene complexes. Three different catalyst systems...... chloride and base. A range of different primary alcohols and amines have been coupled in the presence of the three catalyst systems to afford the corresponding amides in moderate to excellent yields. The best results are obtained with sterically unhindered alcohols and amines. The three catalyst systems do...... not show any significant differences in reactivity, which indicates that the same catalytically active species is operating. The reaction is believed to proceed by initial dehydrogenation of the primary alcohol to the aldehyde that stays coordinated to ruthenium and is not released into the reaction...

  11. Mechanistic investigation of the iridium-catalysed alkylation of amines with alcohols

    DEFF Research Database (Denmark)

    Fristrup, Peter; Tursky, Matyas; Madsen, Robert

    2012-01-01

    The [Cp*IrCl2]2-catalysed alkylation of amines with alcohols was investigated using a combination of experimental and theoretical methods. A Hammett study involving a series of para-substituted benzyl alcohols resulted in a line with a negative slope. This clearly documents that a positive charge......, a line with a negative slope was obtained suggesting that nucleophilic attack on the aldehyde is selectivity-determining. A computational investigation of the entire catalytic cycle with full-sized ligands and substrates was performed using density functional theory. The results suggest a catalytic cycle...... where the intermediate aldehyde stays coordinated to the iridium catalyst and reacts with the amine to give a hemiaminal which is also bound to the catalyst. Dehydration to the imine and reduction to the product amine also takes place without breaking the coordination to the catalyst. The fact...

  12. Adhesion at the interface in cured graphite fiber epoxy-amine resin composites

    Science.gov (United States)

    Needles, Howard L.; Alger, Kenneth W.; Okamoto, Robert

    1987-01-01

    The effect of high temperature curing on the interface between unsized or epoxy-sized graphite fiber tow and epoxy-amine resin was examined by scanning electron microscopy of compression and freeze fractured specimens. Little or no adhesion was found between the unsized graphite fiber tows and the epoxy-amine resin on curing at 165 C for 17 hrs. Epoxy-sized graphite fibers showed a similar lack of adhesion between the fiber tows and the epoxy-amine resin at 3 and 17 hr cures, although good penetration of the resin into the sized fiber tows had occurred. Interfacial bond strengths for the composites could not be effectively measured by compression fracture of specimens.

  13. Nanoindentation study of interphases in epoxy/amine thermosetting systems modified with thermoplastics.

    Science.gov (United States)

    Ramos, Jose Angel; Blanco, Miren; Zalakain, Iñaki; Mondragon, Iñaki

    2009-08-15

    The characterization of a mixture of epoxy/amine with different stoichiometric ratios was carried out by means of nanoindentation. The epoxy system was composed by diglycidyl ether of bisphenol-A and 4,4'-methylene bis-(3-chloro 2,6-diethylaniline). Diffusion through interface formed by epoxy/amine system in stoichiometric ratio and several thermoplastic polymers was also analyzed by means of stiffness analysis, as studied by atomic force microscopy (AFM) and coupled nanoindentation tests. Used thermoplastics were an amorphous, atactic polystyrene, and two semicrystalline, syndiotactic polystyrene and poly(phenylene sulfide). Larger range diffusion was obtained in epoxy/amine systems modified with atactic polystyrene while the study of the influence of stoichiometric ratio suggests that the excess of epoxy generated stiffer material. In addition, larger indentation loads resulted in higher apparent stiffness because of the more number of polymer chains that had to re-accommodate owing to the increase in contact area.

  14. “COLATURA DI ALICI “ CETARESE: EVALUATION OF AMINIC PROFILE

    Directory of Open Access Journals (Sweden)

    A Anastasio

    2008-12-01

    Full Text Available “Colatura d’alici”is a speciality made in Cetara, a clear ,amber-coloured liquid that has sharp taste, prepared with the juice coming from the anchovy salting process. The anchovies are caught in the Gulf of Salerno between the mounths of March and July. The colatura is ready at the beginning of December. Histamine poisoning, a food-borne chemical intoxication caused by the consumption of food containing toxic levels of histamine, is a syndrome commonly associated with the consumption of seafood beloging to the Engraulidae and some fish families. Histamine and biogenic amine levels were determined in “colatura di alici di Cetara”. The amine was separated in a HPLC/FL system. Histamine level were lower than the law limits only in one of the examinated products. A reduction of the histamine and amine levels in colatura cetarese can be obtained using a determinate salt concentrations and changing way of seasoning.

  15. Development of solid amine CO2 control systems for extended duration missions

    Science.gov (United States)

    Dresser, K. J.; Cusick, R. J.

    1984-01-01

    This paper briefly discusses the development history of solid amine CO2 control systems, describes two distinct CO2 control system concepts, and presents the performance characteristics for both system concepts. The first concept (developed under NASA Contract NAS9-13624) incorporates a solid amine canister, an automatic microprocessor controller, and an accumulator to collect CO2 and to provide regulated CO2 delivery to an oxygen recovery system. This system is currently operating in the Crew Systems Division's Advanced Life Support Development Laboratory (ALSDL). The second system concept (being developed under NASA Contract NAS9-16978) employs multiple solid amine canisters, an advanced automatic controller and system status display, the ability to regulate CO2 delivery for oxygen recovery, and energy saving features that allow system operation at lower power levels than the first concept.

  16. Highly efficient heterogeneous procedure for the conjugate addition of amines to electron deficient alkenes

    Institute of Scientific and Technical Information of China (English)

    LIANG XueZheng; QUAN NanNan; WANG Jian; YANG JianGuo

    2009-01-01

    The novel efficient procedure has been developed for the conjugate addition of amines to electron deficient alkenes.K2CO3 supported on different carriers have been synthesized for the conjugate addition of amines and alkenes.After optimizing the reaction conditions,K2CO3/MgO was chosen as the most efficient catalyst for the reactions.The results showed that the catalyst was very efficient for the conjugate addition of amines to electron deficient alkenes with the excellent yields in several minutes.Operational simplicity,without need of any solvent,low cost of the catalyst used,high yields,reusability,excellent chemoselectivity,and applicability to large-scale reactions are the key features of this methodology.

  17. Resolution of water in crude oil emulsion by some novel aromatic amine polyesters

    Directory of Open Access Journals (Sweden)

    A.M. Al-Sabagh

    2015-09-01

    Full Text Available In this work, three aromatic amines (p-toluidine, p-nitroaniline and p-chloroaniline were chosen as bases for the repatriation of some nonionic polyesters. These amines were ethoxylated with different total number of ethylene oxide units 6, 12, 18. The prepared ethoxylated amine diols were polyesterified with maleic anhydride and polypropylene oxide polyethylene oxide block copolymers in polyesterification reaction. The demulsification efficiency of these demulsifiers was investigated using the bottle test. The effects of the molecular weight, concentration, asphaltene content, water content, Hydrophile Lipophile Balance (HLB and temperature on the demulsification efficiency were investigated. The surface active properties were correlated with their demulsification efficiency. It was found that, NAE18D gave the best result in the demulsification process. The demulsification efficiency was discussed on the light of surface active properties, interfacial tension and the factors affecting the demulsification. The surface-active properties of the prepared demulsifiers were measured at 60 °C.

  18. STUDY OF NANOSIZED SILICA GRAFIED WITH HYPERBRANCHED POLY(AMINE-ESTER)

    Institute of Scientific and Technical Information of China (English)

    ZHAO Hui; YANG Shu; LUO Yunjun

    2006-01-01

    A new method to chemically modify the surface of nanosized-SiO2 was studied in this paper. Nanosized-SiO2 was grafted with hyperbranched poly(amin ester) through one-spot polycondensation between AB2 monomer and active hydroxyl on silica surface in present of catalyst.Compared with the results of FTIR and TEM, it is found hyperbranched poly(amin ester) is successfully grafted on the surface of nanosized-SiO2 and the surface properties have been changed with an expected way. The results indicate that nanosized-SiO2 grafted with hyperbranched poly(amin ester) has better dispersion in the ethanol or chloroform than that unmodified.

  19. High production volume chemical Amine Oxide [C8-C20] category environmental risk assessment

    DEFF Research Database (Denmark)

    Sanderson, Hans; Tibazarwa, Caritas; Greggs, William

    2009-01-01

    An environmental assessment of amine oxides has been conducted under the OECD SIDS High Production Volume (HPV) Program via the Global International Council of Chemical Associations (ICCA) Amine Oxides Consortium. Amine oxides are primarily used in conjunction with surfactants in cleaning...... and personal care products. Given the lack of persistence or bioaccumulation, and the low likelihood of these chemicals partitioning to soil, the focus of the environmental assessment is on the aquatic environment. In the United States, the E-FAST model is used to estimate effluent concentrations in the United...... States from manufacturing facilities and from municipal facilities resulting from consumer product uses. Reasonable worst-case ratios of predicted environmental concentration (PEC) to predicted no effect concentration (PNEC) range from 0.04 to 0.003, demonstrating that these chemicals are a low risk...

  20. Efficient acetylation of primary amines and amino acids in environmentally benign brine solution using acetyl chloride

    Indian Academy of Sciences (India)

    Kaushik Basu; Suchandra Chakraborty; Achintya Kumar Sarkar; Chandan Saha

    2013-05-01

    Acetyl chloride is one of the most commonly available and cheap acylating agent but its high reactivity and concomitant instability in water precludes its use to carry out acetylation in aqueous medium. The present methodology illustrates the efficient acetylation of primary amines and amino acids in brine solution by means of acetyl chloride under weakly basic condition in the presence of sodium acetate and/or triethyl amine followed by trituration with aqueous saturated bicarbonate solution. This effort represents the first efficient use of this most reactive but cheap acetylating agent to acetylate amines in excellent yields in aqueous medium. This is a potentially useful green chemical transformation where reaction takes place in environment-friendly brine solution leading to easy work-up and isolation of the amide derivatives. Mechanistic rationale of this methodology is also important.

  1. Click and chemically triggered declick reactions through reversible amine and thiol coupling via a conjugate acceptor

    Science.gov (United States)

    Diehl, Katharine L.; Kolesnichenko, Igor V.; Robotham, Scott A.; Bachman, J. Logan; Zhong, Ye; Brodbelt, Jennifer S.; Anslyn, Eric V.

    2016-10-01

    The coupling and decoupling of molecular units is a fundamental undertaking of organic chemistry. Herein we report the use of a very simple conjugate acceptor, derived from Meldrum's acid, for the sequential ‘clicking’ together of an amine and a thiol in aqueous conditions at neutral pH. Subsequently, this linkage can be ‘declicked’ by a chemical trigger to release the original amine and thiol undisturbed. The reactivity differs from that of other crosslinking agents because the selectivity for sequential functionalization derives from an altering of the electrophilicity of the conjugate acceptor on the addition of the amine. We describe the use of the procedure to modify proteins, create multicomponent libraries and synthesize oligomers, all of which can be declicked to their starting components in a controlled fashion when desired. Owing to the mild reaction conditions and ease of use in a variety of applications, the method is predicted to have wide utility.

  2. Molecular Evolution and Functional Divergence of Trace Amine-Associated Receptors.

    Directory of Open Access Journals (Sweden)

    Seong-Il Eyun

    Full Text Available Trace amine-associated receptors (TAARs are a member of the G-protein-coupled receptor superfamily and are known to be expressed in olfactory sensory neurons. A limited number of molecular evolutionary studies have been done for TAARs so far. To elucidate how lineage-specific evolution contributed to their functional divergence, we examined 30 metazoan genomes. In total, 493 TAAR gene candidates (including 84 pseudogenes were identified from 26 vertebrate genomes. TAARs were not identified from non-vertebrate genomes. An ancestral-type TAAR-like gene appeared to have emerged in lamprey. We found four therian-specific TAAR subfamilies (one eutherian-specific and three metatherian-specific in addition to previously known nine subfamilies. Many species-specific TAAR gene duplications and losses contributed to a large variation of TAAR gene numbers among mammals, ranging from 0 in dolphin to 26 in flying fox. TAARs are classified into two groups based on binding preferences for primary or tertiary amines as well as their sequence similarities. Primary amine-detecting TAARs (TAAR1-4 have emerged earlier, generally have single-copy orthologs (very few duplication or loss, and have evolved under strong functional constraints. In contrast, tertiary amine-detecting TAARs (TAAR5-9 have emerged more recently and the majority of them experienced higher rates of gene duplications. Protein members that belong to the tertiary amine-detecting TAAR group also showed the patterns of positive selection especially in the area surrounding the ligand-binding pocket, which could have affected ligand-binding activities and specificities. Expansions of the tertiary amine-detecting TAAR gene family may have played important roles in terrestrial adaptations of therian mammals. Molecular evolution of the TAAR gene family appears to be governed by a complex, species-specific, interplay between environmental and evolutionary factors.

  3. Synthesis of amphiphilic aminated inulin via 'click chemistry' and evaluation for its antibacterial activity.

    Science.gov (United States)

    Dong, Fang; Zhang, Jun; Yu, Chunwei; Li, Qing; Ren, Jianming; Wang, Gang; Gu, Guodong; Guo, Zhanyong

    2014-09-15

    Inulins are a group of abundant, water-soluble, renewable polysaccharides, which exhibit attractive bioactivities and natural properties. Improvement such as chemical modification of inulin is often performed prior to further utilization. We hereby presented a method to modify inulin at its primary hydroxyls to synthesize amphiphilic aminated inulin via 'click chemistry' to facilitate its chemical manipulation. Additionally, its antibacterial property against Staphylococcus aureus (S. aureus) was also evaluated and the best inhibitory index against S. aureus was 58% at 1mg/mL. As the amphiphilic aminated inulin is easy to prepare and exhibits improved bioactivity, this material may represent as an attractive new platform for chemical modifications of inulin.

  4. Genetically modified CHO cells for studying the genotoxicity of heterocyclic amines from cooked foods

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, L.H.; Wu, R.W.; Felton, J.S.

    1995-07-01

    We have developed metabolically competent CHO cells to evaluate the genotoxicity associated with heterocyclic amines, such as those that are present in cooked foods. Into repair-deficient UV5 cells we introduced cDNAs for expressing cytochrome P450IA2 and acetyltransferases. We then genetically reverted these transformed lines to obtain matched metabolically competent repair-deficient/proficient lines. For a high mutagenic response, we find a requirement for acetyltransferase with IQ but not with PhIP. This system allows for both quantifying mutagenesis and analyzing the mutational spectra produced by heterocyclic amines.

  5. Formation and Human Risk of Carcinogenic Heterocyclic Amines Formed from Natural Precursors in Meat

    Energy Technology Data Exchange (ETDEWEB)

    Knize, M G; Felton, J S

    2004-11-22

    A group of heterocyclic amines that are mutagens and rodent carcinogens form when meat is cooked to medium and well-done states. The precursors of these compounds are natural meat components: creatinine, amino acids and sugars. Defined model systems of dry-heated precursors mimic the amounts and proportions of heterocyclic amines found in meat. Results from model systems and cooking experiments suggest ways to reduce their formation and, thus, to reduce human intake. Human cancer epidemiology studies related to consumption of well-done meat products are listed and compared.

  6. The Effect of Fatty Amine Chain Length on Synthesis Process of Inp/Zns Quantum Dots

    OpenAIRE

    2016-01-01

    Obtaining narrow size distribution through conventional methods used for quantum dots of group II-VI semiconductors is impractical in the case of III-V semiconductors speciallyInP/ZnS quantum dots because of molecular precursors depletion and growth stage continuation through Ostwald ripening process. Using fatty amines as activator along with precursors can lead to more monodispersed quantum dots. In this work, the effect of fatty amine chain length on InP/ZnS quantum dots synthesis was inve...

  7. Synthesis of New N-Arylpyrimidin-2-amine Derivatives Using a Palladium Catalyst

    Directory of Open Access Journals (Sweden)

    So Ha Lee

    2008-04-01

    Full Text Available New N-aryl-4-(pyridin-3-ylpyrimidin-2-amine derivatives were synthesizedfrom the corresponding amines, applying optimized Buchwald-Hartwig aminationconditions using dichlorobis(triphenylphosphinePd(II, xantphos and sodium tertbutoxidein refluxing toluene under a nitrogen atmosphere. The target N-aryl derivativeswere obtained in moderate to good yields ranging from 27% to 82%. The proceduredescribed could be widely employed for the preparation of new heterocyclic compounds.The structures of the new compounds were confirmed by FT-NMR, FT-IR and elementalanalysis.

  8. Biogenic amine content, histamine-forming bacteria, and adulteration of pork in tuna sausage products.

    Science.gov (United States)

    Kung, Hsien-Feng; Tsai, Yung-Hsiang; Chang, Shih-Chih; Hong, Tang-Yao

    2012-10-01

    Twenty-five tuna sausage products were purchased from retail markets in Taiwan. The rates of occurrence of biogenic amines, histamine-forming bacteria, and adulteration by pork and poultry were determined. The average content of various biogenic amines in all tested samples was less than 2.0 mg/100 g (sausage. The fish species in the tuna sausage samples were identified as Thunnus albacares for 22 samples (88%), Thunnus alalunga for 1 sample (4%), and Thunnus thynnus for 1 sample (4%), whereas the remaining sample was identified as Makaira nigricans (blue marlin).

  9. Seasonal variation of aliphatic amines in marine sub-micrometer particles at the Cape Verde islands

    Directory of Open Access Journals (Sweden)

    H. Herrmann

    2009-12-01

    Full Text Available Monomethylamine (MA, dimethylamine (DMA and diethylamine (DEA were detected at non-negligible concentrations in sub-micrometer particles at the Cap Verde Atmospheric Observatory (CVAO located on the island of São Vicente in Cape Verde during algal blooms in 2007. The concentrations of these amines in five stage impactor samples ranged from 0–30 pg m−3 for MA, 130–360 pg m−3 for DMA and 5–110 pg m−3 for DEA during the spring bloom in May 2007 and 2–520 pg m−3 for MA, 100–1400 pg m−3 for DMA and 90–760 pg m−3 for DEA during an unexpected winter algal bloom in December 2007. Anomalously high Saharan dust deposition and intensive ocean layer deepening were found at the Atmospheric Observatory and the associated Ocean Observatory during algal bloom periods. The highest amine concentrations in fine particles (impactor stage 2, 0.14–0.42 μm indicate that amines are likely taken up from the gas phase into the acidic sub-micrometer particles. The contribution of amines to the organic carbon (OC content ranged from 0.2–2.5% C in the winter months, indicating the importance of this class of compounds to the carbon cycle in the marine environment. Furthermore, aliphatic amines originating from marine biological sources likely contribute significantly to the nitrogen content in the marine atmosphere. The average contribution of the amines to the detected nitrogen species in sub-micrometer particles can be non-negligible, especially in the winter months (0.1% N–1.5% N in the sum of nitrate, ammonium and amines. This indicates that these smaller aliphatic amines can be important for the carbon and the nitrogen cycles in the remote marine environment.

  10. Microwave-assisted one step synthesis of 8-arylmethyl-9H-purin-6-amines

    OpenAIRE

    2008-01-01

    Molecular chaperone heat shock protein 90 (Hsp90) is an important target in cancer and neurodegenerative diseases, and has rapidly become the focus of several drug discovery efforts. Among small molecule Hsp90 inhibitors with clinical applicability are derivatives of 8-arylmethyl-9H-purin-6-amine class. Here we report the use of microwave-assisted chemistry for the successful one-pot delivery of 8-arylmethyl-9H-purin-6-amines. We discuss the applicability as well as the limitations of this me...

  11. Direct amination of benzene to aniline with several typical vanadium complexes

    Institute of Scientific and Technical Information of China (English)

    Yu Fen Lv; Liang Fang Zhu; Qiu Yuan Liu; Bin Guo; Xiao Ke Hu; Chang Wei Hu

    2009-01-01

    The liquid-phase direct catalytic amination of benzene to aniline was performed in acetic acid water solvent using a series of vanadium(Ⅲ,Ⅳ,Ⅴ)complexes with N,O-or O,O-ligands as catalysts and hydroxylamine hydrochloride as the aminating agent.The vanadium complexes exhibited much higher selectivity towards the production of aniline than NaVO3 or VOSO4.Under the optimized conditions,an aniline yield of 42.5% and a TON of 48 with a high selectivity of above 99.9% was obtained using 0.2 mmol of[VO(OAc)2]as the catalyst.

  12. Allosteric modulation of semicarbazide-sensitive amine oxidase activities in vitro by imidazoline receptor ligands

    OpenAIRE

    2004-01-01

    Evidence indicates that imidazoline I2 binding sites (I2BSs) are present on monoamine oxidase (MAO) and on soluble (plasma) semicarbazide-sensitive amine oxidase enzymes. The binding site on MAO has been described as a modulatory site, although no effects on activity are thought to have been observed as a result of ligands binding to these sites.We examined the effects in vitro of several imidazoline binding site ligands on activities of bovine plasma amine oxidase (BPAO) and porcine kidney d...

  13. Amine-Oxide Hybrid Materials for CO2 Capture from Ambient Air.

    Science.gov (United States)

    Didas, Stephanie A; Choi, Sunho; Chaikittisilp, Watcharop; Jones, Christopher W

    2015-10-20

    Oxide supports functionalized with amine moieties have been used for decades as catalysts and chromatographic media. Owing to the recognized impact of atmospheric CO2 on global climate change, the study of the use of amine-oxide hybrid materials as CO2 sorbents has exploded in the past decade. While the majority of the work has concerned separation of CO2 from dilute mixtures such as flue gas from coal-fired power plants, it has been recognized by us and others that such supported amine materials are also perhaps uniquely suited to extract CO2 from ultradilute gas mixtures, such as ambient air. As unique, low temperature chemisorbents, they can operate under ambient conditions, spontaneously extracting CO2 from ambient air, while being regenerated under mild conditions using heat or the combination of heat and vacuum. This Account describes the evolution of our activities on the design of amine-functionalized silica materials for catalysis to the design, characterization, and utilization of these materials in CO2 separations. New materials developed in our laboratory, such as hyperbranched aminosilica materials, and previously known amine-oxide hybrid compositions, have been extensively studied for CO2 extraction from simulated ambient air (400 ppm of CO2). The role of amine type and structure (molecular, polymeric), support type and structure, the stability of the various compositions under simulated operating conditions, and the nature of the adsorbed CO2 have been investigated in detail. The requirements for an effective, practical air capture process have been outlined and the ability of amine-oxide hybrid materials to meet these needs has been discussed. Ultimately, the practicality of such a "direct air capture" process is predicated not only on the physicochemical properties of the sorbent, but also how the sorbent operates in a practical process that offers a scalable gas-solid contacting strategy. In this regard, the utility of low pressure drop monolith

  14. NOx reduction using amine reclaimer wastes (ARW) generated in post combustion CO2 capture

    DEFF Research Database (Denmark)

    Botheju, Deshai; Glarborg, Peter; Tokheim, Lars-Andre

    2012-01-01

    Amine reclaimer wastes (ARW) generated in CO2 capture processes demand suitable disposal means. Such wastes contain remaining amine, NH3 and other degradation compounds. This study investigated the potential of using ARW as a NOx reducing agent, under laboratory conditions in a flow reactor....... A simulated flue gas containing about 500 ppm of NO and 5% O2 was injected with liquid ARW under different stoichiometric ratios (TN/NO – total N to nitric oxide ratio) and temperatures. The ARW was obtained from a distillation monoethanolamine reclaimer in an industrial CO2 capture facility with a coal fired...

  15. Bifunctional (cyclopentadienone)iron-tricarbonyl complexes: synthesis, computational studies and application in reductive amination.

    Science.gov (United States)

    Moulin, Solenne; Dentel, Hélène; Pagnoux-Ozherelyeva, Anastassiya; Gaillard, Sylvain; Poater, Albert; Cavallo, Luigi; Lohier, Jean-François; Renaud, Jean-Luc

    2013-12-23

    Reductive amination under hydrogen pressure is a valuable process in organic chemistry to access amine derivatives from aldehydes or ketones. Knölker's complex has been shown to be an efficient iron catalyst in this reaction. To determine the influence of the substituents on the cyclopentadienone ancillary ligand, a series of modified Knölker's complexes was synthesised and fully characterised. These complexes were also transformed into their analogous acetonitrile iron-dicarbonyl complexes. Catalytic activities of these complexes were evaluated and compared in a model reaction. The scope of this reaction is also reported. For mechanistic insights, deuterium-labelling experiments and DFT calculations were undertaken and are also presented.

  16. Mesoporous Niobium Oxide Spheres as an Effective Catalyst for the Transamidation of Primary Amides with Amines

    KAUST Repository

    Ghosh, Subhash Chandra

    2014-02-06

    Mesoporous niobium oxide spheres (MNOS), conveniently prepared by a novel antisolvent precipitation approach, have been shown to be an effective catalyst for the transamidation of primary amides with amines. This novel transamidation can be efficiently carried out under solvent-free conditions and is applicable to a wide range of primary amides and amines to provide N-alkyl amides in good to excellent yields. The catalyst is highly stable and reusable. The application of this transamidation reaction has been demonstrated in the synthesis of antidepressant drug moclobemide and other druglike compounds. © 2014 Wiley-VCH Verlag GmbH&Co. KGaA, Weinheim.

  17. Fluorescence method for enzyme analysis which couples aromatic amines with aromatic aldehydes

    Science.gov (United States)

    Smith, R.E.; Dolbeare, F.A.

    1980-10-21

    Analysis of proteinases is accomplished using conventional amino acid containing aromatic amine substrates. Aromatic amines such as 4-methoxy-2-naphthylamine (4M2NA), 2-naphthylamine, aminoisophthalic acid dimethyl ester, p-nitroaniline, 4-methoxy-1-aminofluorene and coumarin derivatives resulting from enzymatic hydrolysis of the substrate couples with aromatic aldehydes such as 5-nitrosalicylaldehyde (5-NSA), benzaldehyde and p-nitrobenzaldehyde to produce Schiff-base complexes which are water insoluble. Certain Schiff-base complexes produce a shift from blue to orange-red (visible) fluorescence. Such complexes are useful in the assay of enzymes. No Drawings

  18. Fluorescence method for enzyme analysis which couples aromatic amines with aromatic aldehydes

    Science.gov (United States)

    Smith, Robert E.; Dolbeare, Frank A.

    1979-01-01

    Analysis of proteinases is accomplished using conventional amino acid containing aromatic amine substrates. Aromatic amines such as 4-methoxy-2-naphthylamine (4M2NA), 2-naphthylamine, aminoisophthalic acid dimethyl ester, p-nitroaniline, 5-methoxy-1-aminofluorene and coumarin derivatives resulting from enzymatic hydrolysis of the substrate couples with aromatic aldehydes such as 5-nitrosalicylaldehyde (5-NSA), benzaldehyde and p-nitrobenzaldehyde to produce Schiff-base complexes which are water insoluble. Certain Schiff-base complexes produce a shift from blue to orange-red (visible) fluorescence. Such complexes are useful in the assay of enzymes.

  19. Improved Parameterization of Amine-Carboxyate and Amine-Phosphate Interactions for Molecular Dynamics Simulations Using the CHARMM and AMBER Force Fields

    CERN Document Server

    Yoo, Jejoong

    2015-01-01

    Over the past decades, molecular dynamics (MD) simulations of biomolecules have become a mainstream biophysics technique. As the length and time scales amenable to the MD method increase, shortcomings of the empirical force fields---which have been developed and validated using relatively short simulations of small molecules---become apparent. One common artifact is aggregation of water-soluble biomolecules driven by artificially strong charge--charge interactions. Here, we report a systematic refinement of Lennard-Jones parameters (NBFIX) describing amine--carboxylate and amine--phosphate interactions, which brings MD simulations of basic peptide-mediated nucleic acids assemblies and lipid bilayer membranes in better agreement with experiment. As our refinement neither affects the existing parameterization of bonded interaction nor does it alter the solvation free energies, it improves realism of an MD simulation without introducing additional artifacts.

  20. Revisiting noncovalent So2- amine chemistry: an indicator-displacement assay for colorimetric detection of So2.

    Science.gov (United States)

    Leontiev, Alexander V; Rudkevich, Dmitry M

    2005-10-19

    A supramolecular approach for potential detection of SO2 is presented, which is based on the "old" donor-acceptor chemistry between SO2 and amines and includes an indicator-displacement assay. When amines were added to Zn-tetraphenylporphyrin 1 in CHCl3, the solution changed from red to dark green. A bathochromic shift of Deltalambda approximately 10 nm was observed for the Soret band, indicating the formation of 1*amine complexes. After this, SO2 gas was introduced, and the original red color of the solution was restored. The Soret band returned to its position for free porphyrin 1. The 1*amine complexes dissociated, and new SO2*amine adducts formed. Porphyrin 1 thus served as an indirect colorimetric indicator for SO2. The system discriminates between SO2 and such typical exhaust gases as COX, NOX, and H2O. From the indicator-displacement assay, the Kassoc values between 1000 and 30 000 M-1 for SO2*amine complexes were determined, which are comparable to those obtained by direct titration experiments between SO2 and the amines. Spectroscopic features of SO2*amine complexes are also presented.

  1. Palladium-catalyzed aryl amination-heck cyclization cascade: A one-flask approach to 3-substituted Indoles

    DEFF Research Database (Denmark)

    Jensen, Thomas; Pedersen, Henrik; Bang-Andersen, B.;

    2008-01-01

    Two for the price of one: A Pd/dppf-based catalyst provides access to the title compounds from 1,2-dihalogenated aromatic compounds and allylic amines in a single reaction flask. The initial aryl amination step occurs with excellent selectivity for the aryl iodide to ensure the formation of a sin...

  2. Characterization of the in vitro binding and inhibition kinetics of primary amine oxidase/vascular adhesion protein-1 by glucosamine.

    LENUS (Irish Health Repository)

    Olivieri, Aldo

    2012-04-01

    Primary-amine oxidase (PrAO) catalyzes the oxidative deamination of endogenous and exogenous primary amines and also functions, in some tissues, as an inflammation-inducible endothelial factor, known as vascular adhesion protein-1. VAP-1 mediates the slow rolling and adhesion of lymphocytes to endothelial cells in a number of inflammatory conditions, including inflammation of the synovium.

  3. MICROWAVE-ASSISTED CHEMISTRY: SYNTHESIS OF AMINES AND HETEROCYCLES VIA CARBON-NITROGEN BOND FORMATION IN AQUEOUS MEDIA

    Science.gov (United States)

    Improved C-N bond formation under MW influence is demonstrated by a) solventless three-component coupling reaction to generate propargyl amines that uses only Cu (I); b) aqueous N-alkylation of amines by alkyl halides that proceeds expeditiously in the presence of NaOH to deliver...

  4. 40 CFR 721.6183 - Amides, from ammonium hydroxide - maleic anhydride polymer and hydrogenated tallow alkyl amines...

    Science.gov (United States)

    2010-07-01

    ... - maleic anhydride polymer and hydrogenated tallow alkyl amines, sodium salts, compds. with ethanolamine... Substances § 721.6183 Amides, from ammonium hydroxide - maleic anhydride polymer and hydrogenated tallow... anhydride polymer and hydrogenated tallow alkyl amines, sodium salts, compds. with ethanolamine (PMN...

  5. Synthesis of 3-Bromotetronamides via Amination of 3,4-Dibromofuran-2(5H)-one

    Energy Technology Data Exchange (ETDEWEB)

    Cunha, Silvio; Oliveira, Caio C., E-mail: silviodc@ufba.b [Universidade Federal da Bahia (IQ/UFBA), Salvador, BA (Brazil). Inst. de Quimica; Instituto Nacional de Ciencia e Tecnologia (INCT) em Energia, Salvador, BA (Brazil); Sabino, Jose R. [Universidade Federal de Goias (IF/UFG), Goiania (Brazil). Inst. de Fisica

    2011-07-01

    This work describes the direct synthesis of 3-bromotetronamides in good yields through the reaction of 3,4-dibromofuran-2(5H)-one, obtained from furfural, with primary and secondary amines. Aromatic amines were more tolerated than aliphatic and heteroaromatic ones. The X-ray structures of five derivatives are described. (author)

  6. Phospholipophilicity of CxHyN(+) amines : chromatographic descriptors and molecular simulations for understanding partitioning into membranes

    NARCIS (Netherlands)

    Droge, S T J; Hermens, J L M; Rabone, J; Gutsell, S; Hodges, G

    2016-01-01

    Using immobilized artificial membrane high-performance liquid chromatography (IAM-HPLC) the sorption affinity of 70 charged amine structures to phospholipids was determined. The amines contained only 1 charged moiety and no other polar groups, the rest of the molecule being aliphatic and/or aromatic

  7. Ionic liquids as silica deactivating agents in gas chromatography for direct analysis of primary amines in water

    NARCIS (Netherlands)

    Krzyzaniak, A.; Weggemans, W.; Schuur, B.; Haan, de A.B.

    2011-01-01

    Analysis of primary amines in aqueous samples remains a challenging analytical issue. The preferred approach by gas chromatography is hampered by interactions of free silanol groups with the highly reactive amine groups, resulting in inconsistent measurements. Here, we report a method for direct ana

  8. (13)C and (15)N NMR characterization of amine reactivity and solvent effects in CO2 capture.

    Science.gov (United States)

    Perinu, Cristina; Arstad, Bjørnar; Bouzga, Aud M; Jens, Klaus-J

    2014-08-28

    Factors influencing the reactivity of selected amine absorbents for carbon dioxide (CO2) capture, in terms of the tendency to form amine carbamate, have been studied. Four linear primary alkanolamines at varying chain lengths (MEA, 3A1P, 4A1B , and 5A1P ), two primary amines with different substituents in the β-position to the nitrogen (1A2P and ISOB), a secondary alkanolamine (DEA), and a sterically hindered primary amine (AMP) were investigated. The relationship between the (15)N NMR data of aqueous amines and their ability to form carbamate, as determined at equilibrium by quantitative (13)C NMR experiments, was analyzed, taking into account structural-chemical properties. For all the amines, the (15)N chemical shifts fairly reflected the observed reactivity for carbamate formation. In addition to being a useful tool for the investigation of amine reactivity, (15)N NMR data clearly provided evidence of the importance of solvent effects for the understanding of chemical dynamics in CO2 capture by aqueous amine absorbents.

  9. Post-Combustion CO2 Capture Demonstration Using Supported Amine Sorbents: Design and Evaluation of 200 kWth Pilot

    NARCIS (Netherlands)

    Zhao, Wenying; Veneman, Rens; Chen, Denggao; Li, Zhenshan; Cai, Ningsheng; Brilmana, Derk W.F.

    2014-01-01

    CO2 capture using supported amine sorbents is a promising post-combustion capture technology. With regard to supported amine sorbents, the most important issues exist in the regeneration process. In this paper, various regeneration strategies including thermal regeneration in pure CO2 stream, vacuum

  10. Regiospecific oxidation of an alkyl group of aromatic amine to carbonyl group by DDQ in aq.medium

    Institute of Scientific and Technical Information of China (English)

    Madhav S. Mane; Ravi S. Balaskar; Sandip N. Gavade; Pramod N. Pabrekar; Murlidhar S. Shingare; Dhananjay V. Mane

    2011-01-01

    The regiospecific oxidation of alkyl group of both sterically hindered and unhindered aromatic amine to corresponding carbonyl compound was done in aq. medium by using DDQ. The optimized reaction protocol was found to be most simple, high yielding and novel method for oxidation of alkyl group of aromatic amine in to its carbonyl compound.

  11. PEROXISOMAL AMINE OXIDASE OF HANSENULA-POLYMORPHA DOES NOT REQUIRE ITS SRL-CONTAINING C-TERMINAL SEQUENCE FOR TARGETING

    NARCIS (Netherlands)

    FABER, KN; HAIMA, P; DEHOOP, MJ; HARDER, W; VEENHUIS, M; AB, G

    1993-01-01

    Amine oxidase (AMO) is a peroxisomal matrix protein of Hansenula polymorpha, which is induced during growth of the yeast in media containing primary amines as a sole nitrogen source. The deduced amino acid sequence of the protein contains an SRL sequence at nine amino acids from the C-terminus. In t

  12. Continuous Reductive Amination of Biomass-Derived Molecules over Carbonized Filter Paper-Supported FeNi Alloy.

    Science.gov (United States)

    Chieffi, Gianpaolo; Braun, Max; Esposito, Davide

    2015-11-01

    This paper reports the continuous reductive amination of different molecules, including biomass-related compounds, over carbon-supported FeNi nanoparticles obtained on the basis of inexpensive and abundant metal precursors and cellulose. A biorefinery case study for the preparation of pyrrolidones via acid-catalyzed hydrolysis of glucose followed by reductive amination of the obtained levulinic acid is described.

  13. Thieme Chemistry Journal Awardees - Where are They Now? Catalytic Transport with an Amine Carrier in a Fluorous Triphasic Reaction.

    Science.gov (United States)

    Montanari, Vittorio; Yu, Marvin S; Curran, Dennis P

    2009-03-01

    Several aromatic aldehydes are transported by a fluorous amine from one organic phase through a fluorous phase to another organic phase. The derived imines react with phenylhydrazine to immobilize the transported product as a hydrazone and release the amine for reuse. In this way, catalytic transport is accomplished for the first time.

  14. EVIDENCE FOR THE PRESENCE OF MUTAGENIC ARYL AMINES IN HUMAN BREAST MILK AND DNA ADDUCTS IN EXFOLIATED BREAST-DUCT EPITHELIAL CELLS

    Science.gov (United States)

    Aromatic (AA) and heterocyclic amines (HAA) are ubiquitous environmental mutagens present in combustions emissions, fried meats, tobacco smoke, etc., and are suspect human mammary carcinogens. To determine the presence of aryl amines in breast tissue and fluid, we examined exfol...

  15. Degradation of biogenetic amines by gamma radiation process and identification by GC/MS

    Energy Technology Data Exchange (ETDEWEB)

    Cardozo, Monique; Souza, Stefania P. de; Lima, Keila dos S.C.; Lima, Antonio L. dos S., E-mail: santoslima@ime.eb.br [Departamento de Quimica - IME, Instituto Militar de Engenharia, RJ (Brazil)

    2011-07-01

    Biogenic amines are low molecular weight organic bases with aliphatic (putrescine, cadaverine, spermine, spermidine), aromatic (tyramine, phenylethylamine) or heterocyclic (histamine, tryptamine) structures that can be found in several foods, in which they are mainly produced by microbial decarboxylation of amino acids. The reasons to control amines in food are their potential toxicity and their use like food quality markers. The consumption of food containing large amounts of biogenic amines can result in allergic reactions, characterized by difficulty in breathing, rash, vomiting, and hypertension. Biogenic amines are also known as possible precursors of carcinogens, such as N-nitrosamines. Traditionally, biogenic amine formation in food has been prevented, primarily by limiting microbial growth. However, control measures to reduce their levels once formed need to be also considered. The biogenic amines are frequently found in high concentrations and not reduced by high-temperature treatment, which makes difficult to use conventional methods of food preservation for this purpose. Food irradiation has been used in many countries for inhibition of sprouting, destruction of food borne insects, extension of shelf life or improvement of the technological of food. Irradiation is also known as a good method for inactivating pathogens and reducing microorganisms in food materials. Furthermore, besides the sanitary purpose, irradiation technology in new trials can be applied to induce radiolysis of toxic contaminants in food products reducing their content. This study has the objective to evaluate the effect of different gamma irradiation doses (1, 3 and 5kGy) in methanol solutions of three different biogenic amines: tryptamine, tyramine and b-phenylethylamine. The solutions were prepared using standard biogenic amines purchased from Sigma-Aldrich Brazil and methanol HPLC grade with a concentration of 100 {mu}g/mL. They were irradiated in Centro Tecnologico do Exercito

  16. SO2-Resistant Immobilized Amine Sorbents for CO2 Capture

    Energy Technology Data Exchange (ETDEWEB)

    Tumuluri, Uma [Univ. of Akron, OH (United States)

    2014-01-01

    The solid amine sorbent for CO2 capture process has advantages of simplicity and low operating cost compared to the MEA (monoethanolamine) process. Solid amine sorbents reported so far suffered from either low CO2 capture capacity or low stability in the flue gas environment. This project is aimed at developing a SO2-resistant solid amine sorbent for capturing CO2 from coal–fired power plants with SCR/FGD which emits SO2ranging from 15 to 30 ppm and NO ranging from 5 to 10 ppm. The amine sorbent we developed in a previous project degraded rapidly with 65% decrease in the initial capture capacity in presence of 1% SO2. This amine sorbent was further modified by coating with polyethyleneglycol (PEG) to increase the SO2-resistance. Polyethylene glycol (PEG) was found to decrease the SO2-amine interaction, resulting in the decrease in the maximum SO desorption temperature (Tmax ) of amine sorbent. The PEG-coated amine sorbent exhibited higher stability with only 40% decrease in the initial capture capacity compared to un-coated amine sorbents. The cost of the solid amine sorbent developed in this project is estimated to be less than $7.00/lb; the sorbent exhibited CO2 capture capacity more than 2.3 mmol/g. The results of this study provided the scientific basis for further development of SO2-resistant sorbents.

  17. Effect of immobilized amine density on cadmium(II) adsorption capacities for ethanediamine-modified magnetic poly-(glycidyl methacrylate) microspheres

    Science.gov (United States)

    Dong, Tingting; Yang, Liangrong; Pan, Feng; Xing, Huifang; Wang, Li; Yu, Jiemiao; Qu, Hongnan; Rong, Meng; Liu, Huizhou

    2017-04-01

    A series of ethanediamine (EDA) - modified magnetic poly-(glycidyl methacrylate) (m-PGMA-EDA)microspheres with different amine density were synthesized and their cadmium saturation adsorption capacities were examined. The results showed that the cadmium saturation adsorption capacity increased with the immobilized amine density. However, they did not show strong positive linear correlation in the whole range of amine density examined. The molar ratio of amine groups to the adsorbed cadmium decreased with the increase of amine density and eventually reached a minimum value about 4. It suggested that low immobilized amine density led to low coordination efficiency of the amine. It is hypothesized that the immobilized amine groups needed to be physically close enough to form stable amine-metal complex. When the amine density reached to a critical value 1.25 m mol m-2, stable amine-cadmium complex (4:1 N/Cd) was proposed to form. To illustrate the coordination mechanism (structure and number) of amine and Cd, FT-IR spectra of m-PGMA-EDA and m-PGMA-EDA-Cd , and X-ray photoelectron spectroscopy (XPS) of PGMA-EDA and PGMA-EDA-Cd were examined and analyzed.

  18. Nano ZnO/amine composites antimicrobial additives to acrylic paints

    Directory of Open Access Journals (Sweden)

    H.B. Kamal

    2015-12-01

    Full Text Available Nano ZnO has been widely used as an antimicrobial agent not only for food packaging purposes but also in many coating processes. The present work is meant to enhance such functions through the preparation of sustainable and safe conduct of nano ZnO composites with amine derivatives that are characterized by their antimicrobial and anti-fouling functional activities. The results obtained revealed a more comprehensive approach to the antimicrobial function based on the reported active oxide species role. The oxide/amine composites and the acrylic emulsion paint were characterized chemically and structurally through FT-IR, TGA and TEM supported by biological assessment of each ZnO/amine composite action. Results of the study concluded that equilibrium between the nano ZnO particles size, their dispersion form, and amine ability to stabilize the actively produced oxygen species responsible for the antimicrobial function, should all be accounted for when persistence of antimicrobial agent efficiency is regarded.

  19. Impact of Environmental Exposures on the Mutagenicity/Carcinogenicity of Heterocyclic Amines

    Energy Technology Data Exchange (ETDEWEB)

    Felton, J S; Knize, M G; Bennett, L M; Malfatti, M A; Colvin, M E; Kulp, K S

    2003-12-19

    Carcinogenic heterocyclic amines are produced from overcooked foods and are highly mutagenic in most short-term test systems. One of the most abundant of these amines, 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), induces breast, colon and prostate tumors in rats. Human dietary epidemiology studies suggest a strong correlation between either meat consumption or well-done muscle meat consumption and cancers of the colon, breast, stomach, lung and esophagus. For over 20 years our laboratory has helped define the human exposure to these dietary carcinogens. In this report we describe how various environmental exposures may modulate the risk from exposure to heterocyclic amines, especially PhIP. To assess the impact of foods on PhIP metabolism in humans, we developed an LC/MS/MS method to analyze the four major PhIP urinary metabolites following the consumption of a single portion of grilled chicken. Adding broccoli to the volunteers' diet altered the kinetics of PhIP metabolism. At the cellular level we have found that PhIP itself stimulates a significant estrogenic response in MCF-7 cells, but even more interestingly, co-incubation of the cells with herbal teas appear to enhance the response. Numerous environmental chemicals found in food or the atmosphere can impact the exposure, metabolism, and cell proliferation response of heterocyclic amines.

  20. Structure and activity relationships for CO2 regeneration from aqueous amine-based absorbents

    NARCIS (Netherlands)

    Singh, P.; Versteeg, G. F.

    2008-01-01

    A study to determine the relationships between structure and activity of various amine-based CO2 solvents was performed. The desorption of CO2 from saturated solvents at 80 °C and atmospheric pressure was measured to assess the initial desorption rate and desorption capacities at pseudo-equilibrium

  1. Structure and activity relationships for amine based CO2 absorbents-I

    NARCIS (Netherlands)

    Singh, P.; Niederer, J. P. M.; Versteeg, G. F.

    2007-01-01

    A study to determine the structure and activity relationships of various amine based CO2 absorbents was performed in which, the absorption of pure CO2 at atmospheric pressure was measured to assess the total absorption rate and capacities. Results showed that an increase in chain length between the

  2. Structure and activity relationships for amine based CO2 absorbents—II

    NARCIS (Netherlands)

    Singh, Prachi; Niederer, John P.M.; Versteeg, Geert F.

    2009-01-01

    A study to determine the structure and activity relationships of various amine-based CO2 absorbents was performed, in which the absorption of pure CO2 at atmospheric pressure was measured to assess the total absorption rates and capacities. Steric hindrance effect was noticed when side chain with al

  3. Structure and activity relationships for amine based CO2 absorbents—I

    NARCIS (Netherlands)

    Singh, Prachi; Niederer, John P.M.; Versteeg, Geert F.

    2007-01-01

    A study to determine the structure and activity relationships of various amine based CO2 absorbents was performed in which, the absorption of pure CO2 at atmospheric pressure was measured to assess the total absorption rate and capacities. Results showed that an increase in chain length between the

  4. Structure and activity relationships for amine-based CO2 absorbents-II

    NARCIS (Netherlands)

    Niederer, J. P. M.; Versteeg, G. F.

    2009-01-01

    A study to determine the structure and activity relationships of various amine-based CO2 absorbents was performed, in which the absorption of pure CO2 at atmospheric pressure was measured to assess the total absorption rates and capacities. Steric hindrance effect was noticed when side chain with al

  5. New Phase Transfer Agent for Dye:Application for Hyperbranched Poly(ester-amine)

    Institute of Scientific and Technical Information of China (English)

    Teng QIU; Li Ming TANG; Xin Lin TUO; De Shan LIU

    2004-01-01

    Hydrophilic hyperbranched poly(ester-amine) (HPEA) synthesized from diethanolamine and methyl acrylate was used as phase transfer agent for the first time to transfer methyl orange (MO) from water into chloroform.This process was quantified by UV-Vis spectra.A possible mechanism was put forward based on the formation of amphiphilic aggregates.

  6. A new efficient synthesis of isothiocyanates from amines using di-tert-butyl dicarbonate

    DEFF Research Database (Denmark)

    Munch, Henrik; Hansen, Jon S.; Pittelkow, Michael;

    2008-01-01

    Alkyl and aryl amines are converted smoothly to the corresponding isothiocyanates via the dithiocarbamates in good to excellent yields using di-tert-butyl dicarbonate (Boc(2)O) and 1-3 mol% of DMAP or DABCO as catalyst. As most of the byproducts are volatile, the work-up involves simple evaporation...

  7. Palladium-Catalyzed Carbonylation of Primary Amines in Supercritical Carbon Dioxide

    Institute of Scientific and Technical Information of China (English)

    李金恒; 江焕峰; 陈鸣才

    2001-01-01

    The chemoselectity of the palladimm-catalyzed carbonylation of amines was affected by the addition of MeOH in supercritical carbon dioxide. The results show different selectivity in supercritical carbon dioxide CO2(sc) from that in alcohol.Methyl carbamate and its derivatives were obtained in high yields in CO2(sc).

  8. Investigations on organogermanium compounds; III. N-tributylgermyl-substituted aliphatic and heterocyclic amines

    NARCIS (Netherlands)

    Rijkens, F.; Janssen, M.J.; Kerk, G.J.M. van der

    1965-01-01

    A series of new organogermanium compounds containing a germanium‐nitrogen bond, in many of which the nitrogen atom forms part of an heterocyclic ring, are prepared, in some cases by new methods: transamination reactions and reactions of germoxanes with heterocyclic amines. Striking differences in re

  9. N-Heterocyclic Carbene-Palladium Complex Catalyzed Oxidative Carbonylation of Amines to Ureas

    Institute of Scientific and Technical Information of China (English)

    ZHENG,Shu-Zhan; PENG,Xin-Gao; LIU,Jian-Ming; SUN,Wei; XIA,Chun-Gu

    2007-01-01

    Palladium carbene shows high efficiency without any promoter on oxidative carbonylation of amines to ureas and a new type of palladium carbene complex containing both an aniline and an NHC ligands was found to be the active species for the reaction.

  10. Development of an efficient amine-functionalized glass platform by additional silanization treatment with alkylsilane.

    Science.gov (United States)

    Kamisetty, Nagendra Kumar; Pack, Seung Pil; Nonogawa, Mitsuru; Devarayapalli, Kamakshaiah Charyulu; Kodaki, Tsutomu; Makino, Keisuke

    2006-11-01

    Aminosilane-treated molecular layers on glass surfaces are frequently used as functional platforms for biosensor preparation. All the amino groups present on the surface are not available in reactive forms, because surface amino groups interact with remaining unreacted surface silanol groups. Such nonspecific interactions might reduce the efficiency of chemical immobilization of biomolecules such as DNA, enzymes, antibodies, etc., in biosensor fabrication. To improve immobilization efficiency we have used additional surface silanization with alkylsilane (capping) to convert the remaining silanol groups into Si-O-Si linkages, thereby liberating the amino groups from nonspecific interaction with the silanol groups. We prepared different types of capped amine surface and evaluated the effect of capping on immobilization efficiency by investigating the fluorescence intensity of Cy3-NHS (N-hydroxysuccinimide) dye that reacted with amino groups. The results indicate that most of the capped amine surfaces resulted in enhanced efficiency of immobilization of Cy3-NHS compared with the untreated control amine surface. We found a trend that trialkoxysilanes had greater capping effects on immobilization efficiency than monoalkoxysilanes. It was also found that the aliphatic chain of alkylsilane, which does not participate in the capping of the silanol, had an important function in enhancing immobilization efficiency. These results would be useful for preparation of an amine-modified surface platform, with enhanced immobilization efficiency, which is essential for developing many kinds of biosensors on a silica matrix.

  11. Identification of primary amines in Titan tholins using microchip nonaqueous capillary electrophoresis

    Science.gov (United States)

    Cable, M. L.; Hörst, S. M.; He, C.; Stockton, A. M.; Mora, M. F.; Tolbert, M. A.; Smith, M. A.; Willis, P. A.

    2014-10-01

    Titan, the moon of Saturn with a thick atmosphere and an active hydrocarbon-based weather cycle, is considered the best target in the solar system for the study of organic chemistry on a planetary scale. Microfluidic devices that employ liquid phase techniques such as capillary electrophoresis with ultrasensitive laser-induced fluorescence detection offer a unique solution for in situ analysis of complex organics on Titan. We previously reported a protocol for nonaqueous microfluidic analysis of primary aliphatic amines in ethanol, and demonstrated separations of short- and long-chain amines down to -20 °C. We have optimized this protocol further, and used it to analyze Titan aerosol analogues (tholins) generated in two separate laboratories under a variety of different conditions. Ethylamine was a major product in all samples, though significant differences in amine content were observed, in particular for long-chain amines (C12-C27). This work validates microfluidic chemical analysis of complex organics with relevance to Titan, and represents a significant first step in understanding tholin composition via targeted functional group analysis.

  12. Organocatalytic asymmetric allylic amination of Morita–Baylis–Hillman carbonates of isatins

    Directory of Open Access Journals (Sweden)

    Hang Zhang

    2012-08-01

    Full Text Available The investigation of a Lewis base catalyzed asymmetric allylic amination of Morita–Baylis–Hillman carbonates derived from isatins afforded an electrophilic pathway to access multifunctional oxindoles bearing a C3-quaternary stereocenter, provided with good to excellent enantioselectivity (up to 94% ee and in high yields (up to 97%.

  13. Mosher Amides: Determining the Absolute Stereochemistry of Optically-Active Amines

    Science.gov (United States)

    Allen, Damian A.; Tomaso, Anthony E., Jr.; Priest, Owen P.; Hindson, David F.; Hurlburt, Jamie L.

    2008-01-01

    The use of chiral reagents for the derivatization of optically-active amines and alcohols for the purpose of determining their enantiomeric purity or absolute configuration is a tool used by many chemists. Among the techniques used, Mosher's amide and Mosher's ester analyses are among the most reliable and one of the most often used. Despite this,…

  14. Support vector machine for SAR/QSAR of phenethyl-amines

    Institute of Scientific and Technical Information of China (English)

    Bing NIU; Wen-cong LU; Shan-sheng YANG; Yu-dong CAI; Guo-zheng LI

    2007-01-01

    Aim: To discriminate 32 phenethyl-amines between antagonists and agonists,and predict the activities of these compounds. Methods: The support vectormachine (SVM) is employed to investigate the structure-activity relationship(SAR)/quantitative structure-activity relationship (QSAR) of phenethyl-aminesbased on molecular descriptors. Results: By using the leave-one-out cross-vali-dation (LOOCV) test, 1 optimal SAR and 2 optimal QSAR models for agonists andantagonists were attained. The accuracy of prediction for the classification ofphenethyl-amines by using the LOOCV test is 91.67%, and the accuracy of predic-tion for the classification of phenethyl-amines by using the independent test is100%; the results are better than those of the Fisher, the artificial neural network(ANN), and the K-nearest neighbor models for this real world data. The RMSE(root mean square error)of antagonists' QSAR model is 0.5881, and the RMSE ofagonists' QSAR model is 0.4779, which are better than those of the multiple linearregression, partial least squares, and ANN models for this real world data.Conclusion: The SVM can be used to investigate the SAR and QSAR of phenethyl-amines and could be a promising tool in the field of SAR/QSAR research.

  15. Dimethylzinc-Initiated Radical Coupling of β-Bromostyrenes with Ethers and Amines

    DEFF Research Database (Denmark)

    Sølvhøj, Amanda Birgitte; Ahlburg, Andreas; Madsen, Robert

    2015-01-01

    A new coupling reaction has been developed in which β-bromostyrenes react with ethers and tertiary amines to introduce the styryl group in the α-position. The transformation is mediated by Me2Zn/O2 with 10 % MnCl2 and is believed to proceed by a radical addition-elimination mechanism. The ether...

  16. Method of preparing water purification membranes. [polymerization of allyl amine as thin films in plasma discharge

    Science.gov (United States)

    Hollahan, J. R.; Wydeven, T. J., Jr. (Inventor)

    1974-01-01

    Allyl amine and chemically related compounds are polymerized as thin films in the presence of a plasma discharge. The monomer compound can be polymerized by itself or in the presence of an additive gas to promote polymerization and act as a carrier. The polymerized films thus produced show outstanding advantages when used as reverse osmosis membranes.

  17. Palladium-catalysed transannular C-H functionalization of alicyclic amines

    Science.gov (United States)

    Topczewski, Joseph J.; Cabrera, Pablo J.; Saper, Noam I.; Sanford, Melanie S.

    2016-03-01

    Discovering pharmaceutical candidates is a resource-intensive enterprise that frequently requires the parallel synthesis of hundreds or even thousands of molecules. C-H bonds are present in almost all pharmaceutical agents. Consequently, the development of selective, rapid and efficient methods for converting these bonds into new chemical entities has the potential to streamline pharmaceutical development. Saturated nitrogen-containing heterocycles (alicyclic amines) feature prominently in pharmaceuticals, such as treatments for depression (paroxetine, amitifadine), diabetes (gliclazide), leukaemia (alvocidib), schizophrenia (risperidone, belaperidone), malaria (mefloquine) and nicotine addiction (cytisine, varenicline). However, existing methods for the C-H functionalization of saturated nitrogen heterocycles, particularly at sites remote to nitrogen, remain extremely limited. Here we report a transannular approach to selectively manipulate the C-H bonds of alicyclic amines at sites remote to nitrogen. Our reaction uses the boat conformation of the substrates to achieve palladium-catalysed amine-directed conversion of C-H bonds to C-C bonds on various alicyclic amine scaffolds. We demonstrate this approach by synthesizing new derivatives of several bioactive molecules, including varenicline.

  18. The removal of carbon dioxide with activated solutions of methyl-diethanol-amine

    NARCIS (Netherlands)

    van Elk, E. P.; Versteeg, G. F.; van Loo, S.

    2007-01-01

    The (bulk) removal of carbon-dioxide (CO2) from industrial gases, e.g. natural gas, is usually realized with a reactive absorption technique in which (non-)aqueous solutions of alkanolamines are used. From the absorption rate point of view, primary or secondary amines are preferred. However, in case

  19. The removal of carbon dioxide with activated solutions of methyl-diethanol-amine

    NARCIS (Netherlands)

    Loo, van S.; Elk, van E.P.; Versteeg, G.F.

    2007-01-01

    The (bulk) removal of carbon-dioxide (CO2) from industrial gases, e.g. natural gas, is usually realized with a reactive absorption technique in which (non-)aqueous solutions of alkanolamines are used. From the absorption rate point of view, primary or secondary amines are preferred. However, in cas

  20. Support influences in the Pd-catalyzed racemization and dynamic kinetic resolution of chiral benzylic amines

    NARCIS (Netherlands)

    Parvulescu, A.N.; Jacobs, P.A.; De Vos, D.E.

    2009-01-01

    The acid–base properties of the supports for Pd catalysts strongly affect their performance in racemization and dynamic kinetic resolution (DKR) of chiral benzylic amines. The need for a basic support was proven by comparing the racemization results obtained for Pd on silica, on LDH (layered double

  1. Effect of titanium tetrafluoride, amine fluoride and fluoride varnish on enamel erosion in vitro

    NARCIS (Netherlands)

    Vieira, A; Ruben, JL; Huysmans, MCDNJM

    2005-01-01

    This study aimed at evaluating the effect of 1 and 4% titanium tetrafluoride (TiF4) gels, amine fluoride (AmF) 1 and 0.25% and a fluoride varnish (FP) on the prevention of dental erosion. Two experimental groups served as controls, one with no pretreatment and another one pre-treated with a fluoride

  2. New amidines from intramolecular cyclization in triflic acid of nitroketene aminals with a tethered phenyl ring

    Indian Academy of Sciences (India)

    Soro Yaya; Bamba Fanté; Siaka Sorho; Coustard Jean-Marie; Adima A Augustin

    2007-05-01

    Nitroketene aminals with a tethered phenyl group underwent an intramolecular cyclization in trifluoromethanesulfonic acid to afford the corresponding N-(3-ethyl-hydrohydroxyiminobenzocycloalkenylidene) methylamine trifluoromethanesulfonate. The yields were fair to good excepted for the starting compound 1-[N-ethyl-N-(2-phenylethyl)amino]-1-methylamino-2-nitroethene.

  3. Factors Affecting Energy Barriers for Pyramidal Inversion in Amines and Phosphines: A Computational Chemistry Lab Exercise

    Science.gov (United States)

    Montgomery, Craig D.

    2013-01-01

    An undergraduate exercise in computational chemistry that investigates the energy barrier for pyramidal inversion of amines and phosphines is presented. Semiempirical calculations (PM3) of the ground-state and transition-state energies for NR[superscript 1]R[superscript 2]R[superscript 3] and PR[superscript 1]R[superscript 2]R[superscript 3] allow…

  4. Solid-phase oligosaccharide synthesis with tris(alkoxy)benzyl amine (BAL) safety-catch anchoring

    DEFF Research Database (Denmark)

    Tolborg, Jakob Fjord; Jensen, Knud Jørgen

    2000-01-01

    A tris(alkoxy)benzylamine (BAL) handle strategy was developed for safety-catch anchoring of D-glucosamine derivatives in solid-phase synthesis of oligosaccharides; the linkage between the BAL handle and the amine proved stable to conc. TFA and Lewis acids, but after N-acylation the amide could...

  5. 6-Nitro-4H-benzo[d][1,3]thiazin-2-amine

    Directory of Open Access Journals (Sweden)

    Krishna Kumar Gnanasekaran

    2016-05-01

    Full Text Available An efficient and cost-effective synthesis of 6-nitro-4H-benzo[d][1,3]thiazin-2-amine based on a sequential SN2-SNAr process is reported. The synthesis is accomplished with an overall yield of 80%.

  6. Alkylamino derivatives of 4-aminomethylpyridine as inhibitors of copper-containing amine oxidases.

    Science.gov (United States)

    Bertini, Vincenzo; Buffoni, Franca; Ignesti, Giovanni; Picci, Nevio; Trombino, Sonia; Iemma, Francesca; Alfei, Silvana; Pocci, Marco; Lucchesini, Francesco; De Munno, Angela

    2005-02-10

    The first substratelike, reversible inhibitors of different copper amine oxidases (CAOs) with IC50 (M) as low as 2.0 x 10(-8) corresponding to derivatives of 4-aminomethylpyridine with alkoxy (1a-d), alkylthio (2a,b), and alkylamino (3a-e, 4a-j) groups in the positions 3 and 5 have been prepared and studied. The inhibitors 1a-d are active on benzylamine oxidase and semicarbazide-sensitive amine oxidase and are very selective with respect to diamine oxidase, lysyl oxidase, and monoamine oxidases. The inhibitors 2a,b are selective for benzylamine oxidase whereas 2a is also a new type of good substrate of diamine oxidase. The inhibitors 3a-e and 4a-j are substratelike, reversible, nonselective inhibitors of various CAOs including pea seedling amine oxidase and Hansenula polymorpha amine oxidase, whose enzymatic sites are known from X-ray structure determinations. The inhibitors 3b,c and 4b,c are excellent substratelike tools for studies correlating CAOs that afford crystals suitable for X-ray structure determinations with CAOs from mammals.

  7. Density Functional Investigation of Graphene Doped with Amine-Based Organic Molecules

    Directory of Open Access Journals (Sweden)

    Yeun Hee Hwang

    2015-01-01

    Full Text Available To improve the electronic properties of graphene, many doping techniques have been studied. Herein, we investigate the electronic and molecular structure of doped graphene using density functional theory, and we report the effects of amine-based benzene dopants adsorbed on graphene. Density functional theory (DFT calculations were performed to determine the role of amine-based aromatic compounds in graphene doping. These organic molecules bind to graphene through long-range interactions such as π-π interactions and C-H⋯π hydrogen bonding. We compared the electronic structures of pristine graphene and doped graphene to understand the electronic structure of doped graphene at the molecular level. Also, work functions of doped graphene were obtained from electrostatic potential calculations. A decrease in the work function was observed when the amine-based organic compounds were adsorbed onto graphene. Because these systems are based on physisorption, there was no obvious band structure change at point K at the Fermi level after doping. However, the amine-based organic dopants did change the absolute Fermi energy levels. In this study, we showed that the Fermi levels of the doped graphene were affected by the HOMO energy level of the dopants and by the intermolecular charge transfer between the adsorbed molecules and graphene.

  8. Highly water-soluble multi-walled carbon nanotubes amine-functionalized by supercritical water oxidation.

    Science.gov (United States)

    Chun, Kyoung-Yong; Moon, In-Kyu; Han, Joo-Hee; Do, Seung-Hoe; Lee, Jin-Seo; Jeon, Seong-Yun

    2013-11-07

    Multi-walled carbon nanotubes (MWNTs) have been amine-functionalized by eco-friendly supercritical water oxidation. The facilely functionalized MWNTs have high solubility (~84 mg L(-1)) in water and 78% transmittance at 30-fold dilution. The Tyndall effect is also shown for several liquids.

  9. 40 CFR 721.10017 - Amine terminated bisphenol A diglycidyl ether polymer (generic).

    Science.gov (United States)

    2010-07-01

    ... diglycidyl ether polymer (generic). 721.10017 Section 721.10017 Protection of Environment ENVIRONMENTAL... ether polymer (generic). (a) Chemical substances and significant new uses subject to reporting. (1) The chemical substances identified generically as amine terminated bisphenol A diglycidyl ether polymer (PMNs...

  10. 40 CFR 721.2577 - Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine...

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Copper complex of (substituted... Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine salt... substances identified generically as copper complex of (substituted sulfonaphthyl azo substituted...

  11. Surfactant-free Preparation of Highly Stable Zwitterionic Poly(amido amine) Nanogels with Minimal Cytotoxicity

    NARCIS (Netherlands)

    Ekkelenkamp, A.E.; Jansman, M.M.T.; Roelofs-Haarhuis, H.M.; Engbersen, J.F.J.; Paulusse, J.M.J.

    2016-01-01

    Narrowly dispersed zwitterionic poly(amido amine) (PAA) nanogels with a diameter of approximately 100 nm were prepared by a high-yielding and surfactant-free, inverse nanoprecipitation of PAA polymers. The resulting, negatively charged, nanogels (PAA-NG1) were functionalized with N,N-dimethylethylen

  12. Silica Chloride Nano Particle Catalyzed Ring Opening of Epoxides by Aromatic Amines

    Institute of Scientific and Technical Information of China (English)

    Karimian Ramin; Piri Farideh; Karimi Babak; Moghimi Abolghasem

    2011-01-01

    Silica chloride nano particle (nano SiO2-Cl), has been found to be heterogeneous catalyst for facile, simple and mild ring opening of epoxides with aromatic amines to afford β-amino alcohols in dry CH2Cl2 at room temperature.

  13. Gas Permeability and Selectivity of Synthesized Diethanol Amine-Polysulfone/Polyvinylacetate Blend Membranes

    Directory of Open Access Journals (Sweden)

    Asim Mushtaq

    2014-08-01

    Full Text Available The control of anthropogenic carbon dioxide release is one of the most challenging environmental problem faced by developing countries, as the interfering of atmospheric carbon dioxide level and climate revolutionize. An rising technology is the membrane gas separation, which is more dense, energy efficient and possibly more economical than past technologies, such as solvent absorption. Amine has a greater efficiency for removal of carbon dioxide. The blending technique not only provides improved chemical and thermal stability but is also efficient enough to improve the perm-selective properties with economical viability. In this study, research will be carried out to study the gas permeability behavior of glassy Polysulfone and Polyvinyl acetate rubbery polymeric blend membranes with diethanol amine. Polymeric amine blend membranes with different blending ratios were prepared in dimethyl acetamide solvent, flat sheet membrane were developed with enhance properties. We were studied PSU/PVAc blend with DEA amine using a gas permeability application for CO2 and CH4 at different feed pressures.

  14. A Mechanistic Study of Direct Activation of Allylic Alcohols in Palladium Catalyzed Amination Reactions

    NARCIS (Netherlands)

    Gumrukcu, Y.; de Bruin, B.; Reek, J.N.H.

    2015-01-01

    We here report a computational approach on the mechanism of allylicamination reactions using allyl-alcohols and amines as the substrates and phosphoramidite palladium catalyst 1a, which operates in the presence of catalytic amount of 1,3-diethylurea as a co-catalyst. DFT calculations showed a cooper

  15. Mechanistic study on the ruthenium-catalyzed direct amination of alcohols

    NARCIS (Netherlands)

    Pingen, Dennis; Lutz, Martin; Vogt, Dieter

    2014-01-01

    The Ru-catalyzed direct amination of alcohols with ammonia was investigated for the RuHCl(CO)(PPh3)3/Xantphos system in order to gain mechanistic insight. For several Ru(II) precursor complexes the influence of different additives on catalytic performance was investigated. NMR studies revealed that

  16. ANTIMONY HALIDES AND HgX2 (X = Cl, Br AMINE ADDUCTS: SYNTHESIS AND INFRARED STUDY

    Directory of Open Access Journals (Sweden)

    NDONGO GUEYE

    2013-12-01

    Full Text Available Eight new SbF3, SbCl5 and HgX2 (X = Cl, Br amine adducts have been synthesized and their infrared study carried out. Discrete structures have been suggested on the basis of elemental analysis and infrared data, the coordination number of antimony varying from five to nine, while the environment around Hg is tetrahedral.

  17. Metabolic Effects of Dietary Proteins, Amino Acids and The Other Amine Consisting Compounds on Cardiovascular System.

    Directory of Open Access Journals (Sweden)

    Elif Uğur

    2017-02-01

    Full Text Available During the prevention and treatment of cardiovascular diseases, first cause of deaths in the world, diet has a vital role. While nutrition programs for the cardiovascular health generally focus on lipids and carbohydrates, effects of proteins are not well concerned. Thus this review is written in order to examine effect of proteins, amino acids, and the other amine consisting compounds on cardiovascular system. Because of that animal or plant derived proteins have different protein composition in different foods such as dairy products, egg, meat, chicken, fish, pulse and grains, their effects on blood pressure and regulation of lipid profile are unlike. In parallel amino acids made up proteins have different effect on cardiovascular system. From this point, sulfur containing amino acids, branched chain amino acids, aromatic amino acids, arginine, ornithine, citrulline, glycine, and glutamine may affect cardiovascular system in different metabolic pathways. In this context, one carbon metabolism, synthesis of hormone, stimulation of signaling pathways and effects of intermediate and final products that formed as a result of amino acids metabolism is determined. Despite the protein and amino acids, some other amine consisting compounds in diet include trimethylamine N-oxide, heterocyclic aromatic amines, polycyclic aromatic hydrocarbons and products of Maillard reaction. These amine consisting compounds generally increase the risk for cardiovascular diseases by stimulating oxidative stress, inflammation, and formation of atherosclerotic plaque.

  18. Amine Enrichment of Thin-Film Composite Membranes via Low Pressure Plasma Polymerization for Antimicrobial Adhesion.

    Science.gov (United States)

    Reis, Rackel; Dumée, Ludovic F; He, Li; She, Fenghua; Orbell, John D; Winther-Jensen, Bjorn; Duke, Mikel C

    2015-07-15

    Thin-film composite membranes, primarily based on poly(amide) (PA) semipermeable materials, are nowadays the dominant technology used in pressure driven water desalination systems. Despite offering superior water permeation and salt selectivity, their surface properties, such as their charge and roughness, cannot be extensively tuned due to the intrinsic fabrication process of the membranes by interfacial polymerization. The alteration of these properties would lead to a better control of the materials surface zeta potential, which is critical to finely tune selectivity and enhance the membrane materials stability when exposed to complex industrial waste streams. Low pressure plasma was employed to introduce amine functionalities onto the PA surface of commercially available thin-film composite (TFC) membranes. Morphological changes after plasma polymerization were analyzed by SEM and AFM, and average surface roughness decreased by 29%. Amine enrichment provided isoelectric point changes from pH 3.7 to 5.2 for 5 to 15 min of plasma polymerization time. Synchrotron FTIR mappings of the amine-modified surface indicated the addition of a discrete 60 nm film to the PA layer. Furthermore, metal affinity was confirmed by the enhanced binding of silver to the modified surface, supported by an increased antimicrobial functionality with demonstrable elimination of E. coli growth. Essential salt rejection was shown minimally compromised for faster polymerization processes. Plasma polymerization is therefore a viable route to producing functional amine enriched thin-film composite PA membrane surfaces.

  19. Polyvinyl alcohol electrospun nanofibers containing Ag nanoparticles used as sensors for the detection of biogenic amines

    Science.gov (United States)

    Marega, Carla; Maculan, Jenny; Rizzi, Gian Andrea; Saini, Roberta; Cavaliere, Emanuele; Gavioli, Luca; Cattelan, Mattia; Giallongo, Giuseppe; Marigo, Antonio; Granozzi, Gaetano

    2015-02-01

    Polyvinyl alcohol (PVA) electrospun nanofibers containing Ag nanoparticles (NPs) have been deposited on glass substrates. The aim of the work was to test the feasibility of this approach for the detection of biogenic amines by using either the Ag localized surface plasmon resonance quenching caused by the adsorption of amines on Ag NPs or by detecting the amines by surface enhanced Raman spectroscopy (SERS) after adsorption, from the gas phase, on the metal NPs. Two different approaches have been adopted. In the first one an ethanol/water solution containing AgNO3 was used directly in the electrospinning apparatus. In this way, a simple heat treatment of the nanofibers mat was sufficient to obtain the formation of Ag NPs inside the nanofibers and a partial cross-link of PVA. In the second procedure, the Ag NPs were deposited on PVA nanofibers by using the supersonic cluster beam deposition method, so that a beam of pure Ag NPs of controlled size was obtained. Exposure of the PVA mat to the beam produced a uniform distribution of the NPs on the nanofibers surface. Ethylendiamine vapors and volatile amines released from fresh shrimp meat were chemisorbed on the nanofibers mats. A SERS spectrum characterized by a diagnostic Ag-N stretching vibration at 230 cm-1 was obtained. The results allow to compare the two different approaches in the detection of ammines.

  20. UNIQUAC interaction parameters for alkane/amine systems determined by Molecular Mechanics

    DEFF Research Database (Denmark)

    Jonsdottir, Svava Osk; Klein, R. A.; Rasmussen, Kjeld

    1996-01-01

    UNIQUAC interaction parameters have been successfully determined for three alkane/primary amine systems using a Molecular Mechanics method called the Consistent Force Field. Interaction parameters for alkane/alkane and alkane/ketone systems had been determined previously using this method...

  1. Amine modification of nonporous silica nanoparticles reduces inflammatory response following intratracheal instillation in murine lungs.

    Science.gov (United States)

    Morris, Angie S; Adamcakova-Dodd, Andrea; Lehman, Sean E; Wongrakpanich, Amaraporn; Thorne, Peter S; Larsen, Sarah C; Salem, Aliasger K

    2016-01-22

    Amorphous silica nanoparticles (NPs) possess unique material properties that make them ideal for many different applications. However, the impact of these materials on human and environmental health needs to be established. We investigated nonporous silica NPs both bare and modified with amine functional groups (3-aminopropyltriethoxysilane (APTES)) in order to evaluate the effect of surface chemistry on biocompatibility. In vitro data showed there to be little to no cytotoxicity in a human lung cancer epithelial cell line (A549) for bare silica NPs and amine-functionalized NPs using doses based on both mass concentration (below 200μg/mL) and exposed total surface area (below 14m(2)/L). To assess lung inflammation, C57BL/6 mice were administered bare or amine-functionalized silica NPs via intra-tracheal instillation. Two doses (0.1 and 0.5mg NPs/mouse) were tested using the in vivo model. At the higher dose used, bare silica NPs elicited a significantly higher inflammatory response, as evidence by increased neutrophils and total protein in bronchoalveolar lavage (BAL) fluid compared to amine-functionalized NPs. From this study, we conclude that functionalization of nonporous silica NPs with APTES molecules reduces murine lung inflammation and improves the overall biocompatibility of the nanomaterial.

  2. Epoxidation reaction of perfluoroalkenes with tert-amine N-oxide

    Institute of Scientific and Technical Information of China (English)

    Xing Wei Cai; Min Sha; Biao Jiang; Ren Ming Pan

    2012-01-01

    Straight-chain aliphatic tert-amine N-oxides were found to be useful oxidizing agent for epoxidation of tri-and tetra-substituted perfluoroalkenes under mild conditions in high yields.The process for epoxidation by employing tri-n-butylamine N-oxide gave the best result in the reagent survey.

  3. Biologically active amines in fermented and non-fermented commercial soybean products from the Spanish market.

    Science.gov (United States)

    Toro-Funes, N; Bosch-Fuste, J; Latorre-Moratalla, M L; Veciana-Nogués, M T; Vidal-Carou, M C

    2015-04-15

    Biologically active amines were determined in commercial soybean products. The antioxidant polyamines were found in both non-fermented and fermented soybean products. Natto and tempeh showed the highest content of polyamines (75-124 and 11-24 mg/kg of spermidine and spermine, respectively). On the other hand, the bacterial-related biogenic amines, tyramine, histamine, tryptamine and β-phenylethylamine, were detected in practically all fermented products with a high variability. The highest contents were found in sufu, tamari and soybean paste. Extremely high tyramine and histamine contents, 1700 and 700 mg/kg, respectively, found in some sufu samples could be unhealthy. However, biogenic amines observed in the other soybean products should not be a risk for healthy consumers. However, individuals who take monoamine and diamine oxidase inhibitors drugs should be strongly recommended to avoid this kind of products in order to suffer no adverse health effects. These biogenic amines were not detected in non-fermented soybean products.

  4. Detection and quantification of biogenic amines in fermented food products sold in Botswana.

    Science.gov (United States)

    Magwamba, Clement; Matsheka, Maitshwarelo Ignatius; Mpuchane, Sisai; Gashe, Berhanu Abegaz

    2010-09-01

    The incidence and concentrations associated with four important biogenic amines in leading commercial fermented beverages consumed in Botswana were determined using high-performance liquid chromatography. In 87 sorghum brew and 84 sour milk (madila, amasi) samples tested, putrescine was the most prevalent biogenic amine (63 and 61%, respectively), while histamine was the least prevalent (24 and 8%, respectively). Cadaverine was the most frequently detected biogenic amine in 79 of the commercial sour maize beverage (mageu/mahewu) samples tested (found in 70% of the samples), while tyramine was the least detected (occurring in 3% of the samples). In sorghum brew and sour milk, tyramine was found to be the most concentrated (mean concentration of 2.08 mg/100 ml and 3.2 mg/100 ml, respectively), and histamine was found to be the least concentrated (mean concentration of 0.94 mg/100 ml and 0.31 mg/100 ml, respectively). Overall, the biogenic amine concentrations of all three fermented products were within acceptable limits. However, one sorghum brew sample had a histamine content of 5.8 mg/ 100 ml, which was above the 5.0 mg/100 g allowable limit suggested by the U.S. Food and Drug Administration.

  5. The Use of Amine Reclaimer Wastes as a NOx Reduction Agent

    DEFF Research Database (Denmark)

    Botheju, Deshai; Glarborg, Peter; Tokheim, Lars-Andre

    2013-01-01

    Amine reclaimer wastes (ARW) generated in carbon capture and sequestration (CCS) is categorized as a hazardous waste which needs proper disposal. The proposal described in this paper can bring about a multi-effective solution to the problem of CCS waste handling. Both the pilot scale and the full...

  6. A wet electrostatic precipitator (WESP) as countermeasure to mist formation in amine based carbon capture

    NARCIS (Netherlands)

    Mertens, J.; Anderlohr, C.; Rogiers, P.; Brachert, L.; Khakharia, P.M.; Goetheer, E.L.V.; Schaber, K.

    2014-01-01

    This study is to our knowledge the first to evaluate the potential of a wet electrostatic precipitator (WESP) to prevent aerosol formation issues inside amine based carbon capture installations. A WESP is a suitable option since this study proves that it is very efficient for the removal of the mist

  7. The N-terminus of amine oxidase of Hansenula polymorpha contains a peroxisomal targeting signal

    NARCIS (Netherlands)

    Faber, Klaas Nico; Keizer-Gunnink, Ineke; Pluim, Dick; Harder, Willem; AB, Geert; Veenhuis, Marten

    1995-01-01

    Here we describe the identification of the targeting sequence of peroxisomal amine oxidase (AMO) of H. polymorpha. Deletion analysis revealed that essential targeting information is located within the extreme N-terminal 16 amino acids. Moreover, this sequence can direct a reporter protein to the per

  8. Copper and amine free Sonogashira cross-coupling reaction catalyzed by efficient diphosphane-palladium catalyst

    Institute of Scientific and Technical Information of China (English)

    Ting He; Lei Lei Wu; Xing Li Fu; Hai Yan Fu; Hua Chen; Rui Xiang Li

    2011-01-01

    The commercially available diphosphane ligand MeO-BIPHEP was first investigated in the palladium-catalyzed Sonogashira reaction in the absence of copper and amine. The coupling of various aryl bromides and aryl chlorides with phenylacetylene gave moderate to excellent yields.

  9. Capture and separation of CO2 from flue gas by coupling free and immobilized amines

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A novel system has been proposed for the capture and separation of CO2 from flue gas. In this method, a resin isemployed to regenerate the amine capturing CO2 from flue gas atroom temperatures. The feasibility for the resin to regenerateamines such as MEA, MAE, TEA, and ammonia has been demonstrated. It was also discovered that the resin could be regenerated by hotwater.

  10. Carbon Dioxide Capture from Air Using Amine-Grafted Porous Polymer Networks

    NARCIS (Netherlands)

    Lu, W.; Sculley, J.P.; Yuan, D.; Krishna, R.; Zhou, H.C.

    2013-01-01

    Amine-grafted porous polymer networks were investigated for CO2 capture directly from air (400 ppm CO2, 78.96% N-2, and 21% O-2). Under these ultradilute conditions, PPN-6-CH(2)DETA has an extraordinarily high CO2 selectivity (3.6 x 10(10)) and loading capacity (1.04 mol/kg) as calculated using idea

  11. Adsorption of H2O and CO2 on supported amine sorbents

    NARCIS (Netherlands)

    Veneman, Rens; Frigka, Natalia; Zhao, Wenying; Li, Zhenshan; Kersten, Sascha; Brilman, Wim

    2015-01-01

    In this work the adsorption of H2O and CO2 on Lewatit VP OC 1065 was studied in view of the potential application of this sorbent in post combustion CO2 capture. Both CO2 and H2O were found to adsorb on the amine active sites present on the pore surface of the sorbent material. However, where the in

  12. Capturing atmospheric CO2 using supported amine sorbents for microalgae cultivation

    NARCIS (Netherlands)

    Brilman, D.W.F.; Garcia, Alba L.; Veneman, R.

    2013-01-01

    In this work, we propose, demonstrate and evaluate the concept of atmospheric CO2 capture for enhanced algae cultivation (and horticulture), as alternative to the application of flue gas derived CO2. A supported amine sorbent was prepared and able to capture CO2 at atmospheric conditions and releasi

  13. Efficient CO2 capture and photoreduction by amine-functionalized TiO2.

    Science.gov (United States)

    Liao, Yusen; Cao, Shao-Wen; Yuan, Yupeng; Gu, Quan; Zhang, Zhenyi; Xue, Can

    2014-08-11

    Amine-functionalization of TiO2 nanoparticles, through a solvothermal approach, substantially increases the affinity of CO2 on TiO2 surfaces through chemisorption. This chemisorption allows for more effective activation of CO2 and charge transfer from excited TiO2 , and significantly enhances the photocatalytic rate of CO2 reduction into methane and CO.

  14. Asymmetric α-amination of 3-substituted oxindoles using chiral bifunctional phosphine catalysts

    Directory of Open Access Journals (Sweden)

    Qiao-Wen Jin

    2016-04-01

    Full Text Available A highly enantioselective α-amination of 3-substituted oxindoles with azodicarboxylates catalyzed by amino acids-derived chiral phosphine catalysts is reported. The corresponding products containing a tetrasubstituted carbon center attached to a nitrogen atom at the C-3 position of the oxindole were obtained in high yields and with up to 98% ee.

  15. Guidance document on fat reduction factor, functional barrier concept, phthalates and primary aromatic amines

    DEFF Research Database (Denmark)

    Hoekstra, Eddo J.; Petersen, Jens Højslev; Bustos, Juana

    and the functional barrier, and the restrictions for certain phthalates and primary aromatic amines. The Regulation applies from 1 May 2011. The network of the European Union Reference Laboratory and the National Reference Laboratories for food contact materials created a Task Force in order to give guidance...

  16. Chromium(VI) reduction by catechol(amine)s results in DNA cleavage in vitro

    DEFF Research Database (Denmark)

    Pattison, D I; Davies, Michael Jonathan; Levina, A;

    2001-01-01

    ) or 4-tert-butylcatechol (5) do not damage DNA. The Cr(VI)/catechol(amine) reactions have been studied at low added H(2)O(2) concentrations, which lead to enhanced DNA cleavage with 1 and induce DNA cleavage with 4. The Cr(V) and organic intermediates generated by the reactions of Cr(VI) with 1 or 4...

  17. Modulation of biogenic amines content by poly(propylene imine) dendrimers in rats.

    Science.gov (United States)

    Ciepluch, Karol; Ziemba, Barbara; Janaszewska, Anna; Appelhans, Dietmar; Klajnert, Barbara; Bryszewska, Maria; Fogel, Wiesława Agnieszka

    2012-09-01

    Biogenic amines and polyamines participate in all vital organism functions, their levels being important function determinants. Studies were performed to check whether repeated administration of poly(propylene imine) (PPI) dendrimers, synthetic macromolecules with diaminobutane core, and peripheral primary amine groups, may influence the endogenous level of amines, as represented by the two of them: spermidine, a natural derivative of diaminobutane, and histamine. The experiment was carried out on Wistar rats. Fourth generation PPI dendrimer, as well as maltotriose-modified fourth generation PPI dendrimers with (a) cationic open sugar shell and (b) neutral dense sugar shell that possess a higher biocompatibility, was used. Applying the combination of column chromatography on Cellex P and spectrofluorimetric assays of o-phthaldialdehyde, the final amine condensation products were employed to analyze tissue spermidine and histamine outside the central nervous system. Furthermore, radioenzymatic assay was used to measure histamine levels in the brain. The obtained results indicate that in some tissues, the endogenous concentrations of histamine and spermidine may be affected by dendrimers depending on their dose and type of dendrimers.

  18. Pyrylium Salts as Reactive Matrices for MALDI-MS Imaging of Biologically Active Primary Amines

    Science.gov (United States)

    Shariatgorji, Mohammadreza; Nilsson, Anna; Källback, Patrik; Karlsson, Oskar; Zhang, Xiaoqun; Svenningsson, Per; Andren, Per E.

    2015-06-01

    Many neuroactive substances, including endogenous biomolecules, environmental compounds, and pharmaceuticals possess primary amine functional groups. Among these are catecholamine neurotransmitters (e.g., dopamine), many substituted phenethylamines (e.g., amphetamine), as well as amino acids and neuropeptides. In most cases, mass spectrometric (ESI and MALDI) analyses of trace amounts of such compounds are challenging because of their poor ionization properties. We present a method for chemical derivatization of primary amines by reaction with pyrylium salts that facilitates their detection by MALDI-MS and enables the imaging of primary amines in brain tissue sections. A screen of pyrylium salts revealed that the 2,4-diphenyl-pyranylium ion efficiently derivatizes primary amines and can be used as a reactive MALDI-MS matrix that induces both derivatization and desorption. MALDI-MS imaging with such matrix was used to map the localization of dopamine and amphetamine in brain tissue sections and to quantitatively map the distribution of the neurotoxin β- N-methylamino-L-alanine.

  19. Plaque formation and lactic acid production after use of amine fluoride/stannous fluoride mouthrinse

    NARCIS (Netherlands)

    Gerardu, V.A.M.; Buijs, M.; Loveren, C. van; Cate, J.M. ten

    2007-01-01

    The aim of this study was lo determine the effects of 3 wk of daily rinsing with amine fluoride/stannous fluoride (AmF/SnF2) mouthrinse on plaque formation at buccal and interproximal sites, and on the acid production in plaque. in a randomized clinical trial with 30 participants. The amount of plaq

  20. Photoinduced Electron Transfer (PET) between C60 and Amines in Micelle Solution - A Kinetic ESR Study

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    As indicated by kinetic ESR measurements, the key factor to affect electron recombination in the process of PET between C60 and amines is the space between donor and C60. To increase solubility of C60 in water, it was incorporated into micelle of surfactants.

  1. Construction of bis-, tris- and tetrahydrazones by addition of azoalkenes to amines and ammonia

    Directory of Open Access Journals (Sweden)

    Artem N. Semakin

    2016-11-01

    Full Text Available Exhaustive Michael-type alkylations of amines and ammonia with azoalkenes (generated from α-halohydrazones were demonstrated as an efficient approach to poly(hydrazonomethylamines – a novel class of polynitrogen ligands. An intramolecular cyclotrimerization of C=N bonds in tris(hydrazonomethylamine to the respective 1,4,6,10-tetraazaadamantane derivative was demonstrated.

  2. Color test for selective detection of secondary amines on resin and in solution

    DEFF Research Database (Denmark)

    Boas, Ulrik; Mirsharghi, Sahar

    2014-01-01

    Resins for solid-phase synthesis give orange to red-brown resin beads selectively when secondary amines are present on the resin when treated with a solution of acetaldehyde and an Fmoc-amino acid in NMP. The method shows good specificity and gives colorless beads when exposed to a variety of oth...

  3. Primary aromatic amines (PAAs) in black nylon and other food-contact materials, 2004-2009

    DEFF Research Database (Denmark)

    Trier, Xenia Thorsager; Okholm, B.; Foverskov, Annie

    2010-01-01

    Primary aromatic amines (PAAs) were analysed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) in migrates from 234 samples of food-contact materials, including black nylon (polyamide) kitchen utensils (n = 136), coloured plastics (28), and clear/printed multilayer film/laminates (41...

  4. Highly porous organic polymers bearing tertiary amine group and their exceptionally high CO2 uptake capacities

    Science.gov (United States)

    Gomes, Ruth; Bhaumik, Asim

    2015-02-01

    We report a very simple and unique strategy for synthesis of a tertiary amine functionalized high surface area porous organic polymer (POP) PDVTA-1 through the co-polymerization of monomers divinylbenzene (DVB) and triallylamine (TAA) under solvothermal reaction conditions. Two different PDVTA-1 samples have been synthesized by varying the molar ratio of the monomers. The porous polymeric materials have been thoroughly characterized by solid state 13C CP MAS-NMR, FT-IR and UV-vis spectroscopy, N2 sorption, HR TEM and FE SEM to understand its chemical environment, nanostructure, bonding, morphology and related surface properties. PDVTA-1 with higher amine content (DVB/TAA=4.0) showed exceptionally high CO2 uptake capacity of 85.8 wt% (19.5 mmol g-1) at 273 K and 43.69 wt% (9.93 mmol g-1) at 298 K under 3 bar pressure, whereas relatively low amine loaded material (DVB/TAA=7.0) shows uptake capacity of 59.2 wt% (13.45 mmol g-1) at 273 K and 34.36 wt% (7.81 mmol g-1) at 298 K. Highly porous nanostructure together with very high surface area and basicity at the surface due to the presence of abundant basic tertiary amine N-sites in the framework of PDVTA-1 could be responsible for very high CO2 adsorption.

  5. Cancer risk assessment of azo dyes and aromatic amines from garment and footwear

    NARCIS (Netherlands)

    Zeilmaker MJ; Kroese ED; Haperen P van; Veen MP van; Bremmer HJ; Kranen HJ van; Wouters MFA; Janus J; LBM

    1999-01-01

    A quantitative assessment was performed to estimate the cancer risk to individuals wearing garment and footwear coloured with azo dyes. Basically, the risk assessment consists of both a comparison of the (estimated) level of aromatic amines which, during the wearing of garment and footwear, enters

  6. Rodent repellent studies. IV. Preparation and properties of trinitrobenzene-aryl amine complexes

    Science.gov (United States)

    DeWitt, J.B.; Bellack, E.; Welch, J.F.

    1953-01-01

    Data are presented on methods of preparation, chemical arid physical characteristics, toxicity, and repellency to rodents of complexes of symmetrical trinitrohenzene with various aromatic amines: When applied in suitable carriers or incorporated in plastic .films, members of this series ofmaterials were shown to offer significant increases in time required by wild rodents to damage common packaging materials.

  7. Gold nanoparticles assisted characterization of amine functionalized polystyrene multiwell plate and glass slide surfaces

    Science.gov (United States)

    Dharanivasan, Gunasekaran; Rajamuthuramalingam, Thangavelu; Michael Immanuel Jesse, Denison; Rajendiran, Nagappan; Kathiravan, Krishnan

    2015-01-01

    We demonstrated citrate-capped gold nanoparticles assisted characterization of amine functionalized polystyrene plate and glass slide surfaces through AuNPs staining method. The effect of AuNPs concentration on the characterization of amine modified surfaces was also studied with different concentration of AuNPs (ratios 1.0-0.0). 3-Aminopropylyl triethoxy silane has been used as amine group source for the surface modification. The interactions of AuNPs on modified and unmodified surfaces were investigated using atomic force microscopy and the dispersibility, and the aggregation of AuNPs was analyzed using UV-visible spectrophotometer. Water contact angle measurement and X-ray photoelectron spectroscopy (XPS) were used to further confirmation of amine modified surfaces. The aggregation of AuNPs in modified multiwell plate leads to the color change from red to purple and they are found to be adsorped on the modified surfaces. Aggregation and adsorption of AuNPs on the modified surfaces through the electrostatic interactions and the hydrogen bonds were revealed by XPS analysis. Remarkable results were found even in the very low concentration of AuNPs (ratio 0.2). This AuNPs staining method is simple, cost-effective, less time consuming, and required very low concentration of AuNPs. These results can be read out through the naked eye without the help of sophisticated equipments.

  8. The Reactions of 3,7—Dinitrodibenzobromolium Salt with Some Amines

    Institute of Scientific and Technical Information of China (English)

    ZiJieHOU; XianHuaPAN; 等

    2002-01-01

    The reactions of 3,7-dinitrodibenzobromolium salt with some amines were studied. A reaction mechanism based on the structure of the major product 6 and the minor product 7 was proposed. The reaction was considered to proceed via a substituted benzyene intermediate.

  9. Synthesis of Novel 5-(-Substituted-Anilino)-8-Hydroxyquinolines via Hartwig-Buchwald Amination Reaction

    Indian Academy of Sciences (India)

    Walaa A E Omar; Osmo E O Hormi

    2015-11-01

    Three novel 5-(-substituted-anilino)-8-benzyloxyquinoline derivatives were efficiently synthesized via Hartwig–Buchwald amination reaction. The new 5-(-substituted-anilino)-8-benzyloxyquinolines were reduced for 1–3 h to give the corresponding 5-(-substituted-anilino)-8-hydroxyquinolines. Extending the reduction reaction time to 7 h afforded the corresponding 1,2,3,4-tetrahydro-8-hydroxyquinoline derivatives.

  10. Enzymatic resolution of racemic amines in a continuous reactor in organic solvents.

    Science.gov (United States)

    Gutman, A L; Meyer, E; Kalerin, E; Polyak, F; Sterling, J

    1992-10-05

    An enzymatic process has been developed for the continuous production of the pharmaceutically important intermediate (R)-1-aminoindan and of the chiral resolving agent (R)-1-(1-naphthyl)ethylamine. The process consists of the subtilisin catalyzed stereoselective aminolysis of the racemic primary amine with an active ester in organic solvent. The competing nonenzymatic reaction has been suppressed by appropriate choice of solvent and reactant's concentration and by minimizing the time of contact between the amine and the active ester. Subtilisin was immobilized on glass beads and the reaction carried out in a continuous-flow column bioreactor. By using a 450-mL column bioreactor containing 5.7 g of subtilisin immobilized on 570 g of glass beads, 1.6 kg of racemic 1-(1-naphthyl)ethylamine was resolved after 320 h of continuous operation with only a slight loss of the enzymatic activity. During the whole process, the optical purity of the chiral amine eluting from the column was higher than 90%. A facile procedure was developed for separating the unreacted (R)-amine from the (S)-amide and for the recycling of the solvent 3-methyl-3-pentanol and the active ester 2,2,2-trifluoroethyl butyrate.

  11. Amine donor and acceptor influence on the thermodynamics of ω-transaminase reactions

    DEFF Research Database (Denmark)

    Gundersen, Maria T.; Abu, Rohana; Schürmann, Martin

    2015-01-01

    In recent years biocatalytic transamination using ω-transaminase has become established as one of the most interesting routes to synthesize chiral amines with a high enantiomeric purity, especially in the pharmaceutical sector where the demand for such compounds is high. Nevertheless, one limitat...

  12. Enthalpic, entropic, and square gradient contributions to the surface energetics of amine-cured epoxy systems.

    Science.gov (United States)

    Mezzenga, Raffaele; Page, Stéphane A; Månson, Jan-Anders E

    2002-06-01

    The evolution of surface tension during polymerization of three amine-cured epoxy systems was investigated. Due to the chemical reaction of the epoxy groups with primary and secondary amines, the energetic status of an epoxy-amine system increased during polymerization. At the same time, the polymerization process induced entropic variations, also contributing to the evolution of surface energetics. A simple relation expressing the surface tension as a function of the bulk energy, the entropy of the system, and the square gradient of the polymer density was derived. The bulk and surface energetics were expressed in terms of solubility parameter and surface tension, respectively. The former was predicted using the Van Krevelen group contribution method, while the latter was directly measured using the Wilhelmy wetting method. Results indicated that, in all the three epoxy-amine systems under investigation, a unique relationship combining the surface tension, the bulk energy, the entropy, and the density square gradient of the system could be used. On the basis of the present study, and taking into account all contributory factors, it was concluded that the enthalpy component to the surface energetics is the dominant contribution.

  13. Interface effects on tunneling magnetoresistance in organic spintronics with flexible amine-Au links.

    Science.gov (United States)

    Gorjizadeh, Narjes; Quek, Su Ying

    2013-10-18

    Organic spintronics is a promising emerging field, but the sign of the tunneling magnetoresistance (TMR) is highly sensitive to interface effects, a crucial hindrance to applications. A key breakthrough in molecular electronics was the discovery of amine-Au link groups that give a reproducible conductance. Using first-principles calculations, we predict that amine-Au links give improved reproducibility in organic spintronics junctions with Au-covered Fe leads. The Au layers allow only states with sp character to tunnel into the molecule, and the flexibility of amine-Au links results in a narrow range of TMR for a fixed number of Au layers. Even as the Au thickness changes, the TMR remains positive as long as the number of Au layers is the same on both sides of the junction. Since the number of Au layers on Fe surfaces or Fe nanoparticles can now be experimentally controlled, amine-Au links provide a route towards robust TMR in organic spintronics.

  14. Anomalous length dependence of conductance of aromatic nanoribbons with amine anchoring groups

    KAUST Repository

    Bilić, Ante

    2012-09-06

    Two sets of aromatic nanoribbons, based around a common hexagonal scaffolding, with single and dual terminal amine groups have been considered as potential molecular wires in a junction formed by gold leads. Charge transport through the two-terminal device has been modeled using density functional theory (with and without self-interaction correction) and the nonequilibrium Green\\'s function method. The effects of wire length, multiple terminal contacts, and pathways across the junction have been investigated. For nanoribbons with the oligopyrene motif and conventional single amine terminal groups, an increase in the wire length causes an exponential drop in the conductance. In contrast, for the nanoribbons with the oligoperylene motif and dual amine anchoring groups the predicted conductance rises with the wire length over the whole range of investigated lengths. Only when the effects of self-interaction correction are taken into account, the conductance of the oligoperylene ribbons exhibits saturation for longer members of the series. The oligoperylene nanoribbons, with dual amine groups at both terminals, show the potential to fully harness the highly conjugated system of π molecular orbitals across the junction. © 2012 American Physical Society.

  15. Synthesis of novel aminated cellulose microsphere adsorbent for efficient Cr(VI) removal

    Science.gov (United States)

    Yu, Tianlin; Liu, Siqi; Xu, Min; Peng, Jing; Li, Jiuqiang; Zhai, Maolin

    2016-08-01

    A novel aminated cellulose microsphere adsorbent (CVN) was successfully prepared by radiation-induced graft polymerization of vinylbenzyl chloride (VBC) onto cellulose microsphere (CMS), followed by amination. Micro-FTIR, XPS and SEM confirmed the structure of CVN. The adsorption behavior of Cr(VI) onto CVN from solution was well fitted by the pseudo-second order kinetic model. The isothermal adsorption of Cr(VI) was observed at pH 4.68 with adsorption capacity of 129 mg/g in accordance with Langmuir thermal model, and the removal of Cr(VI) from solution could be 91% at a low amount (20 mg) of adsorbent. The best pH for adsorption of Cr(VI) was nearly 3.08, and with the increasing of temperature, the adsorption capacity of Cr(VI) increased. XPS analysis confirmed the adsorption mechanism of Cr(VI) was ion-exchange mechanism, while common co-ions such as Na+, Mg2+, Cu2+, Ca2+, Zn2+, Ni2+, Cl-, NO3- has no significant effect on the adsorption capacity of Cr(VI), and the Cr(VI) removal of 80% still could be obtained compared with that of fresh CVN adsorbent. Finally, spent CVN could be regenerated under 2 mol/L NaCl. The work indicated that aminated cellulose adsorbent could be prepared successfully by radiation-induced grafting and amination and CVN is a promising bio-adsorbent in the removing Cr(VI) from waste water.

  16. Post-combustion Carbon Dioxide Capture using Amine Functionalized Solid Sorbents

    Science.gov (United States)

    Mittal, Nikhil

    This work is divided into two parts: (1) Synthesis of amine functionalized adsorbents using grafting technique for post-combustion CO2 capture, (2) Performance evaluation of structured bed configuration with straight gas flow channels using amine impregnated adsorbent for post-combustion CO 2 capture. Brief description of each part is given below: (1) N-(3-trimethoxysilylpropyl)diethylenetriamine (DAEAPTS) grafted SBA-15 adsorbents were synthesized for CO2 capture. The adsorption of CO2 on the amine-grafted sorbents was measured by thermogravimetric method over a CO2 partial pressure range of 8--101.3 kPa and a temperature range of 25--105 °C under atmospheric pressure. The optimal amine loaded SBA-15 adsorbent was examined for multi-cycle stability and adsorption/desorption kinetics. (2) The performance of structured bed and packed bed configurations for post-combustion CO2 capture was evaluated using PEI impregnated SBA-15 adsorbent. The effect of adsorption temperature (25-90 °C), adsorption /desorption kinetics and multi-cycle stability was studied in both structured and packed bed configurations.

  17. Plant and Soil Emissions of Amines and Amino Acids: A Source of Secondary Aerosol Precursors

    Science.gov (United States)

    Jackson, M. L.; Doskey, P. V.; Pypker, T. G.

    2011-12-01

    Ammonia (NH3) is the most abundant alkaline gas in the atmosphere and forms secondary aerosol by neutralizing sulfuric and nitric acids that are released during combustion of fossil fuels. Ammonia is primarily emitted by cropping and livestock operations. However, C2 and C3 amines (pKb 3.3-3.4), which are stronger bases than NH3 (pKb 4.7) have been observed in nuclei mode aerosol that is the precursor to secondary aerosol. Mixtures of amines and amino acids have been identified in diverse environments in aerosol, fog water, cloud water, the soluble fraction of precipitation, and in dew. Glycine (pKb 4.2), serine (pKb 4.8) and alanine (pKb 3.7 and 4.1 for the D and L forms, respectively) are typically the most abundant species. The only reported values of gas-phase glycine, serine and alanine were in marine air and ranged from 6-14 pptv. The origin of atmospheric amines and amino acids has not been fully identified, although sources are likely similar to NH3. Nitrate assimilation in plants forms glycine, serine, and L-alanine, while D-alanine is present in bacterial cell walls. Glycine is converted to serine during C3 plant photorespiration, producing CO2 and NH3. Bacteria metabolize glycine and alanine to methylamine and ethylamine via decarboxylation. Likely sources of amino acids are plants and bacteria, thus concentrations near continental sources are likely greater than those measured in marine air. The overall goal of the research is to examine seasonal variations and relationships between the exchange of CO2, NH3, amines, and amino acids with a corn/soybean rotation in the Midwest Corn Belt. The study presents gaseous profiles of organic amine compounds from various species of vegetation using a mist chamber trapping technique and analysis of the derivatized species by high pressure liquid chromatography with fluorescence detection. Amino acid and amine profiles were obtained for red oak (Quercus rubra), sugar maple (Acer saccharinum), white pine (Pinus

  18. Properties of epoxy-amine networks containing nanostructured ether-crosslinked domains

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, Ying-Gev, E-mail: yhsu@mail.ntust.edu.tw [Department of Material Science and Engineering, National Taiwan University of Science and Technology, Taipei 106, Taiwan (China); Lin, Kuan-Hung; Lin, Tse-Yu; Fang, Yi-Lung [Department of Material Science and Engineering, National Taiwan University of Science and Technology, Taipei 106, Taiwan (China); Chen, Su-Chen; Sung, Yi-Ching [Department of Raw Materials and Yarns, Taiwan Textile Research Institute, New Taipei, Taiwan (China)

    2012-02-15

    Highlights: Black-Right-Pointing-Pointer The epoxy-amine networks with nanostructured ether-crosslinked domains (NECDs) was obtained. Black-Right-Pointing-Pointer The morphology of the networks dispersed with 10-30-nm-sized NECDs was investigated by AFM. Black-Right-Pointing-Pointer The molecular-level cavity in the matrix was inferred by a molecular-size simulation. Black-Right-Pointing-Pointer The fracture toughness of the networks were reinforced up to 1.35 times that of neat epoxy. Black-Right-Pointing-Pointer The networks were more thermostable than the neat epoxy because of higher cross-linking. - Abstract: Epoxy-amine networks with a nanodomain toughener-soft nanostructured ether-crosslinked domains (NECDs), which could increase the fracture and tensile toughness of the networks, were simply obtained when a mixture of diglycidyl ether bisphenol A (DGEBA) epoxy resin and 4,4 Prime -methylene dianiline (MDA) hardener was heat-cured in the presence of varying amounts of the imidazole derivatives (called imidazoles)-1-methylimidazole (1-MI) or 2-methylimidazole (2-MI). Under these conditions, the epoxide groups in DGEBA underwent not only polyaddition with the aromatic amine of the MDA to form a hard epoxy-amine networked matrix but also anionic ring-opening polymerization by itself to build soft NECDs connected to the epoxy-amine matrix. The curing chemistry of the DGEBA/MDA mixture, both with and without the imidazoles, was studied using differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR). The morphology of the networks dispersed with 5-30-nm-sized NECDs was investigated by atomic force microscopy (AFM). When the optimum amount ({approx}0.15-0.30 wt%) of imidazoles was added, the NECDs were effective in significantly increasing the tensile and fracture toughness and the thermal stability of the epoxy-amine networks without markedly sacrificing the glass transition temperature (T{sub g}). The novel toughening mechanism and

  19. Sequestering uranium from UO2(CO3)3(4-) in seawater with amine ligands: density functional theory calculations.

    Science.gov (United States)

    Guo, Xiaojing; Huang, Liangliang; Li, Cheng; Hu, Jiangtao; Wu, Guozhong; Huai, Ping

    2015-06-14

    The polystyrene-supported primary amine -CH2NH2 has shown an at least 3-fold increase in uranyl capacity compared to a diamidoxime ligand on a polystyrene support. This study aims to understand the coordination of substitution complexes from UO2(CO3)3(4-) and amines using density functional theory calculations. Four kinds of amines (diethylamine (DEA), ethylenediamine (EDA), diethylenetriamine (DETA) and triethylenetetramine (TETA)) were selected because they belong to different classes and have different chain lengths. The geometrical structures, electronic structures and the thermodynamic stabilities of various substitution complexes, as well as the trends in their calculated properties were investigated at equilibrium. In these optimized complexes, DEA groups bind to uranyl as monodentate ligands; EDA groups serve as monodentate and bidentate ligands; DETA groups act as monodentate and tridentate ligands; while TETA groups serve as monodentate, bidentate and tridentate ligands. The thermodynamic analysis confirmed that the primary amines coordinate to uranyl more strongly than does the secondary amine. The stabilities of substitution complexes with primary amines were calculated to decrease with increasing chain length of the amine, except for UO2(L2)(2+). Of the complexes analyzed, only UO2L(CO3)2(2-) (L = EDA and DETA) and UO2L2CO3 (L = EDA) were predicted to form from the substitution reactions with UO2(CO3)3(4-) and protonated amines as reactants in aqueous solution. Amines were calculated to be comparable to, or sometimes weaker than, amidoximate in replacing CO3(2-) in UO2(CO3)3(4-) to coordinate to uranium. Therefore, the coordination mechanism, in which amines replace carbonates to bind to uranyl, is not primarily responsible for the experimentally observed 3-fold or greater increase in uranyl capacity of primary amines compared to a diamidoxime ligand. Based on the results of our calculations, we believe that the cation exchange mechanism, in which the

  20. Emission of Trimethylamine from Chenopodium vulvaria - first results from quantifiying plant emissions of amines

    Science.gov (United States)

    Sun, Shang; Neftel, Albrecht; Jörg, Sintermann; Derstroff, Bettina; Sauvage, Carina; Bohley, Katharina; Kadereit, Gudrun; Williams, Jonathan; Pöhlker, Christopher; Kesselmeier, Jürgen; Sörgel, Matthias

    2016-04-01

    Amines comprise a wide range of nitrogenous organic compounds such as aliphatic methylamines MA. TMA is the most common amine species emitted by various sources and the most abundant amine in the atmosphere (Ge et al., 2011a). Additionally, TMA has been found to be the dominant amine species in the gas-phase compared to MMA and DMA at agriculture sites (Schade and Crutzen, 1995). On the global scale, the knowledge about the fluxes of most amines is limited (Ge et al., 2011a). Furthermore, terrestrial vegetation is also assumed to be a potential source for amines (Schade and Crutzen, 1995). There are a few studies from the end of the 19th century until 1975, which described high amount of MA-emission from certain plant species, which was associated with their plant tissues or with blossoms during flowering (Smith, 1971). Despite the low atmospheric concentration of amines (DMA = 0.5 ppb (Okita, 1970), TMA = 0.6 -1.6 ppb (Fujii and Kitai, 1987)), previous studies have already shown that amines play an important role in the New aerosol Particle Formation (NPF) (Almeida et al., 2013, and summarized in Sintermann and Neftel, 2015). In the atmosphere, NPF occurs frequently from gas-phase precursors. High uncertainty exists in the estimation of the global secondary aerosols budget, which was cause to the uncertain contribution of the gas-phase precursors to the NPF (Spracklen et al., 2011). It becomes more clearly that instead of binary systems of sulfuric acid and water, ternary system of sulfuric acid, water and a neutralizing compound as NH3 or amines is a key system in NPF (Almeida et al., 2013, Kurten et al., 2014). Despite their low atmospheric concentrations amines may play, at least locally, a crucial role in aerosol formation. In this study, we focus on the plant species chenopodium vulvaria, which is well known as a strong TMA-emitter (Dessaignes, 1856). But TMA emission rates from that plant species was not determined systematically up to now. In this study, we