Literatura académica sobre el tema "Quaternary amine compound"
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Artículos de revistas sobre el tema "Quaternary amine compound"
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Stenholm, Åke, Anders Backlund, Sara Holmström, Maria Backlund, Mikael Hedeland y Petra Fransson. "Survival and growth of saprotrophic and mycorrhizal fungi in recalcitrant amine, amide and ammonium containing media". PLOS ONE 16, n.º 9 (1 de septiembre de 2021): e0244910. http://dx.doi.org/10.1371/journal.pone.0244910.
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The elimination of hazardous compounds in chemical wastes can be a complex and technically demanding task. In the search for environmental-friendly technologies, fungal mediated remediation and removal procedures are of concern. In this study, we investigated whether there are fungal species that can survive and grow on solely amine-containing compounds. One compound containing a primary amine group; 2-diethylaminoethanol, one compound with a primary amide group; 2,6-dichlorobenzamide (BAM), and a third compound containing a quaternary ammonium group; N3-trimethyl(2-oxiranyl)methanaminium chloride, were selected. The choice of these compounds was motivated by their excessive use in large scale manufacturing of protein separation media (2-diethylaminoethanol and the quaternary amine). 2,6-dichlorobenzamide, the degradation product of the herbicide 2,6-dichlorobenzonitrile (dichlobenil), was chosen since it is an extremely recalcitrant compound. Utilising part of the large fungal diversity in Northern European forests, a screening study using 48 fungal isolates from 42 fungal species, including saprotrophic and mycorrhizal fungi, was performed to test for growth responses to the chosen compounds. The ericoid (ERM) mycorrhizal fungus Rhizoscyphus ericae showed the best overall growth on 2-diethylaminoethanol and BAM in the 1–20 g L-1 concentration range, with a 35-fold and 4.5-fold increase in biomass, respectively. For N3-trimethyl(2-oxiranyl)methanaminium chloride, the peak growth occurred at 1 g L-1. In a second experiment, including three of the most promising fungi (Laccaria laccata, Hygrophorus camarophyllus and Rhizoscyphus ericae) from the screening experiment, a simulated process water containing 1.9% (w/v) 2-diethylaminoethanol and 0.8% (w/v) N3-trimethyl(2-oxiranyl)methanaminium chloride was used. Laccaria laccata showed the best biomass increase (380%) relative to a control, while the accumulation for Rhizoscyphus ericae and Hygrophorus camarophyllus were 292% and 136% respectively, indicating that mycorrhizal fungi can use amine- and amide-containing substrates as nutrients. These results show the potential of certain fungal species to be used in alternative green wastewater treatment procedures.
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Wang, Bo, An-Jun Deng, Zhi-Hong Li, Nan Wang y Hai-Lin Qin. "Syntheses and Structure–Activity Relationships in Growth Inhibition Activity against Human Cancer Cell Lines of 12 Substituted Berberine Derivatives". Molecules 25, n.º 8 (18 de abril de 2020): 1871. http://dx.doi.org/10.3390/molecules25081871.
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In this study, quaternary berberine chloride is used as a lead compound to design and synthesize a series of berberine-12-amine derivatives to evaluate the growth inhibition activity against human cancer cell lines. Forty-two compounds of several series were obtained. The quaternary berberine-12-N,N-di-n-alkylamine chlorides showed the targeted activities with the IC50 values of most active compounds being dozens of times those of the positive control. A significant structure–activity relationship (SAR) was observed. The activities of quaternary berberine-12-N,N-di-n-alkylamine chlorides are significantly stronger than those of the reduced counterparts. In the range of about 6-8 carbon atoms, the activities increase with the elongation of n-alkyl carbon chain of 12-N,N-di-n-alkylamino, and when the carbon atom numbers are more than 6-8, the activities decrease with the elongation of n-alkyl carbon chain. The activities of the tertiary amine structure are significantly higher than that of the secondary amine structure.
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Wang, Ming Yang, Mao Sheng Wan y Cheng Bo Cao. "Synthesis and Properties of the Composite DSD Acid-Triazine Structure Containing Long-Chain Quaternary Ammonium Fluorescent Brighteners". Applied Mechanics and Materials 260-261 (diciembre de 2012): 83–86. http://dx.doi.org/10.4028/www.scientific.net/amm.260-261.83.
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The cetyl \ octadecyl dimethyl tertiary amine（percentage composition 7:3）is a very common and inexpensive chemical raw material in the chemical market. In this paper, a series of the new chemical composite DSD acid-triazine structure containing long chain quaternary ammonium salt fluorescent brighteners (FBs) were synthesized through a three-step condensation reaction of cyanuric chloride, DSD acid, cetyl \ octadecyl dimethyl tertiary amine and amino compound. The obtained compounds were characterized by the analysis of the IR spectrum, UV spectrum and fluorescence excitation and emission spectrum, and whiteness were tested through dyeing filter paper. The results show that compounds 7a-j have the obvious UV absorption, fluorescence emission and dyeing properties, with a wider absorption, emission wavelength range and enhancing fluorescence quantum yield, achieving the synergetic enhancement effect by compounding.
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Jeyaprabha, C., S. Muralidharan, D. Jayaperumal, G. Venkatachari y N. S. Rengaswamy. "Studies on corrosion inhibitors for oil‐well tubular material in acid environments". Anti-Corrosion Methods and Materials 45, n.º 3 (1 de junio de 1998): 148–52. http://dx.doi.org/10.1108/00035599810216812.
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To reduce the corrosion of oil‐ and gas‐well equipment during acid treatment, the acid must be inhibited. The behaviour of N‐80 oilfield material in 15 per cent hydrochloric acid solution inhibited by different inhibitor formulations containing amine, ester and a quaternary ammonium compound was studied at 303K for five hours by the mass loss method. The corrosion rates were obtained by polarisation. Impedance studies were carried out to evaluate the performance of the inhibitor formulations. It was found that the formulation containing 3,000ppm amine, 1,000ppm ester and 1,000ppm quaternary ammonium compound was effective for the specific oil‐well tubular material.
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Zhang, Hu y Fu Rong Zhou. "Study on Synthesis of Alkynoxymethyl Benzyl Quaternary Ammonium Salt and its Corrosion Inhibition for Blast Furnace Gas Pipeline". Applied Mechanics and Materials 672-674 (octubre de 2014): 684–87. http://dx.doi.org/10.4028/www.scientific.net/amm.672-674.684.
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Two kinds of alkynoxymethyl benzyl quaternary ammonium salt (ABQAS) were synthesized by raw materials of paraformaldehyde, propiolic alcohol, organic amine, benzyl chloride and ethanol under nitrogen protection, toluene as carrying agent. The products were characterized by FTIR. According to the characteristics of blast furnace gas pipeline, quaternary ammonium salt type compound corrosion inhibitor formulas were designed, and their corrosion inhibition performance were evaluated by weight-loss method and electrochemical method. The results showed that the products were synthesized as expected, the two kinds of products had excellent inhibition performance to the cathode electrochemical process of A3 carbon steel, and the corrosion inhibition efficiency in simulative blast furnace gas reached to 100%.
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Yudovin-Farber, Ira, Jacob Golenser, Nurit Beyth, Ervin I. Weiss y Abraham J. Domb. "Quaternary Ammonium Polyethyleneimine: Antibacterial Activity". Journal of Nanomaterials 2010 (2010): 1–11. http://dx.doi.org/10.1155/2010/826343.
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Quaternary ammonium polyethyleneimine- (QA-PEI-) based nanoparticles were synthesized using two synthetic methods, reductive amination and N-alkylation. According to the first method, QA-PEI nanoparticles were synthesized by cross-linking with glutaraldehyde followed by reductive amination with octanal and further N-methylation with methyl iodide. The second method is based on crosslinking with dialkyl halide followed by N-alkylation with octyl halide and further N-methylation with methyl iodide. QA-PEI nanoparticles completely inhibited bacterial growth (>106bacteria), including both Gram-positive, that is,Staphylococcus aureusat 80 g/mL, and Gram-negative, that is,Escherichia coliat 320 g/mL. Activity analysis revealed that the degree of alkylation and N-methylation of the QA-PEI nanoparticles plays a significant role in antibacterial activity of the reagent. The most potent compound was octyl alkylated QA-PEI alkylated at 1 : 1 mole ratio (primary amine of PEI monomer units/alkylating agent). Also, cytotoxicity studies on MAT-LyLu and MBT cell lines were performed with QA-PEI nanoparticles. These findings confirm previous reports that polycations bearing quaternary ammonium moieties inhibit bacterial growthin vitroand have a potential use as additives in medical devices which need antibacterial properties.
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Gotlib, Elena M., Аlmira R. Khasanova, Engel R. Galimov y Аlla G. Sokolova. "Epoxy antifriction wollastonite-filled materials". Vestnik MGSU, n.º 3 (marzo de 2019): 311–21. http://dx.doi.org/10.22227/1997-0935.2019.3.311-321.
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Introduction. Domestic mineral natural-origin filler ‘wollastonite’, also known as calcium methyl silicate, is widely used as a base for wear-resisting epoxy antifriction materials. Due to anisodiametric shape of its particles, wollastonite functions as a micro reinforcement fibre enhancing adhesion strength and wear resistance of epoxy compositions, improving their antifriction properties, especially when organomodifying by quaternary ammonium salts. In this regard, the investigation of the impact of chemical composition of such surfactants as quaternary ammonium salts on the properties of epoxy compound materials presents utmost interest for researchers developing low-friction materials. Materials and methods. Epoxy diane resin ED-20 was hardened with aminoalkylphenol AF-2. Content of epoxy hardener was determined by equimolar ratio of epoxy groups to amine groups. Domestic wollastonite of the grade Miwoll 10-97 was used as filler, particle length to the diameter correlated as 15:1. The wollastonite surface was activated with surfactants belonging to domestically produced quaternary ammonium salts. Wear resistance of specimens was tested by means of the vertical optical caliper IZV-1. Friction coefficient was estimated with the assistance of the computer-automated frictional machine CSM Instruments Tribometer. Adhesion strength of glue joint was determined as per GOST 28840-90 standard. Two bars of sheet aluminium were used as glued surfaces as per GOST 14759-69 standard. Results. Reduction of wear of epoxy coatings when modified with micro reinforcing wollastonite can be explained by the increase of cross-linking degree of the polymer. The length of alkyl radical of quaternary ammonium salts used for wollastonite surface activation affects the intervals between the epoxy links. As the quaternary ammonium salt chain length is growing, wear of epoxy materials is reducing. Introduction of the wollastonite containing metallic oxides in the epoxy composites increases wear resistance and adhesion strength and reduces coating friction coefficients. Conclusions. Hardened with the AF-2 and filled with the wollastonite of the Miwoll 10-97 grade, the epoxy compound materials have enhanced wear resistance and adhesion strength and lower friction coefficient. The best result is observed when applying wollastonite modified with a surfactant belonging to the class of quaternary ammonium salts. The wollastonite can be used for practical purposes as a perspective reinforcing agent for epoxy materials with improved wear resistance, enhanced adhesion to metals and reduced friction coefficient.
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Zaytsev, Vladimir P., Elena A. Sorokina, Elisaveta A. Kvyatkovskaya, Flavien A. A. Toze, Shashank N. Mhaldar, Pavel V. Dorovatovskii y Victor N. Khrustalev. "Three-component reaction between isatoic anhydride, amine and methyl-substituted furylacrylaldehydes: crystal structures of 3-benzyl-2-[(E)-2-(5-methylfuran-2-yl)vinyl]-2,3-dihydroquinazolin-4(1H)-one, 3-benzyl-2-[(E)-2-(furan-2-yl)-1-methylvinyl]-2,3-dihydroquinazolin-4(1H)-one and 3-(furan-2-ylmethyl)-2-[(E)-2-(furan-2-yl)-1-methylvinyl]-2,3-dihydroquinazolin-4(1H)-one". Acta Crystallographica Section E Crystallographic Communications 74, n.º 8 (13 de julio de 2018): 1101–6. http://dx.doi.org/10.1107/s2056989018009982.
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Compounds (I), C22H20N2O2, (II), C22H20N2O2 and (III), C20H18N2O3 are the products of three-component reactions between isatoic anhydride, the corresponding amine and 3-(5-methylfuran-2-yl)- or (furan-2-yl)-2-methylacrylaldehyde. Compound (I) crystallizes in the monoclinic space group P21/n, while compounds (II) and (III) are isostructural and crystallize in the orthorhombic space group Pbca. The tetrahydropyrimidine ring in (I)–(III) adopts a sofa conformation. The NH nitrogen atom has a trigonal–pyramidal geometry, whereas the N(R) nitrogen atom is flattened. The furyl-vinyl substituents in (I)–(III) are practically planar and have an E configuration at the C=C double bond. In (I), this bulky fragment occupies the axial position at the quaternary carbon atom of the tetrahydropyrimidine ring, whereas in (II) and (III) it is equatorially disposed. In the crystal of (I), molecules form hydrogen-bonded chains propagating along [001] by strong intermolecular N—H...O hydrogen bonds. The chains are packed in stacks along the a-axis direction. In the crystals of (II) and (III), molecules also form hydrogen-bonded chains propagating along [100] by strong intermolecular N—H...O hydrogen bonds. However, despite the fact that compounds (II) and (III) are isostructural, steric differences between the phenyl and furyl substituents result in chains with different geometries. Thus in the crystal of (II) the chains have a zigzag-like structure, whereas in the crystal of (III), they are almost linear. In both (II) and (III), the hydrogen-bonded chains are further packed in stacks along the b-axis direction.
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Horrigan, F. T. y W. F. Gilly. "Methadone block of K+ current in squid giant fiber lobe neurons." Journal of General Physiology 107, n.º 2 (1 de febrero de 1996): 243–60. http://dx.doi.org/10.1085/jgp.107.2.243.
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Voltage-dependent ionic currents were recorded from squid giant fiber lobe neurons using the whole-cell patch-clamp technique. When applied to the bathing solution, methadone was found to block IK, I Na and I Ca. Both I Na and I Ca were reduced without apparent change in kinetics and exhibited IC(50)'s of 50-100 and 250-500 mu M, respectively, at +10 mV. In contrast, IK was reduced in a time-dependent manner that is well fit by a simple model of open channel block (K(D)= 32+/- or 2 mu M, +60 mV, 10 degrees Celsius). The mechanism of I(K) block was examined in detail and involves a direct action of methadone, a tertiary amine, on K channels rather than an opioid receptor-mediated pathway. The kinetics of I(K) block resemble those reported for internally applied long chain quaternary ammonium (QA) compounds; and recovery from I(K) block is QA-like in its slow time course and strong dependence on holding potential. A quaternary derivative of methadone (N-methyl-methadone) only reproduced the effects of methadone on I(K) when included in the pipette solution; this compound was without effect when applied externally. I(K) block thus appears to involve diffusion of methadone into the cytoplasm and occlusion of the open K channel at the internal QA blocking site by the protonated form of the drug. This proposed mode of action is supported by the pH and voltage dependence of block as well as by the observation that high external K+ speeds the rate of drug dissociation. In addition, the effect of methadone on I(K) evoked during prolonged (300 ms) depolarizations suggests that methadone block may interfere with endogenous K+ channel inactivation. The effects of temperature, methadone stereoisomers, and the methadone-like drugs propoxyphene and nor-propoxyphene on IK block were examined. Methadone was also found to block I(K) in GH3 cells and in chick myoblasts.
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Han, Hua, Chang Liu, Jie Zhu, Fa-Xue Li, Xue-Li Wang, Jian-Yong Yu, Xiao-Hong Qin y De-Qun Wu. "Contact/Release Coordinated Antibacterial Cotton Fabrics Coated with N-Halamine and Cationic Antibacterial Agent for Durable Bacteria-Killing Application". International Journal of Molecular Sciences 21, n.º 18 (7 de septiembre de 2020): 6531. http://dx.doi.org/10.3390/ijms21186531.
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Coating a cationic antibacterial layer on the surface of cotton fabric is an effective strategy to provide it with excellent antibacterial properties and to protect humans from bacterial cross-infection. However, washing with anionic detergent will inactivate the cationic antibacterial coating. Although this problem can be solved by increasing the amount of cationic antibacterial coating, excessive cationic antibacterial coating reduces the drapability of cotton fabric and affects the comfort of wearing it. In this study, a coordinated antibacterial coating strategy based on quaternary ammonium salt and a halogenated amine compound was designed. The results show that the antibacterial effect of the modified cotton fabric was significantly improved. In addition, after mechanically washing the fabric 50 times in the presence of anionic detergent, the antibacterial effect against Staphylococcus aureus and Escherichia coli was still more than 95%. Furthermore, the softness of the obtained cotton fabric showed little change compared with the untreated cotton fabric. This easy-to-implement and cost-effective approach, combined with the cationic contact and the release effect of antibacterial agents, can endow cotton textiles with durable antibacterial properties and excellent wearability.
Tesis sobre el tema "Quaternary amine compound"
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Tas, Baki Tugrul. "An Experimental Investigation Of The Shale Inhibition Properties Of A Quaternary Amine Compound". Master's thesis, METU, 2013. http://etd.lib.metu.edu.tr/upload/12615554/index.pdf.
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Depleting oil reserves and increased costs of the oil and gas recoveries have created the need to drill
in challenging formations. When drilled through, shale formations in particular always generated a
wide variety of problems if conventional water-based muds are used. Furthermore, the complexity and
variations in shales have compounded the task of developing suitable drilling fluids. In light of these
problems, the study of shale properties and their interactions with fluids will continue to be a muchneeded
source of information in drilling industry.
In this study a low molecular weight quaternary amine compound, which is provided by KarKim
Drilling Fluids Inc., and its mixtures with sodium and potassium chloride is investigated in the aspects
of capillary suction times, hot rolling recoveries, methylene blue capacities and one-dimensional free
swelling properties in order to compare performances of salts and amine compound.
For all test methods quaternary amine concentration from 1% to 6% by volume were studied and seen
that less amount of quaternary amine compound is needed in order to obtain close shale recoveries
and shale volume change potential if compared with sodium and potassium chloride. This prevents the
usage of high concentration of chlorides and hence provides environmental sensitiveness.
Furthermore, it was concluded that combining an amount of salt with quaternary amine compound
gives the system enhanced shale inhibition properties.
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Jacoby, Denis. "Synthese et reactivite des cyclopropanes actives". Paris 6, 1987. http://www.theses.fr/1987PA066439.
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Ce travail decrit des mises au point originales de preparations de pyrrolines et de dihydrofurannes a partir de cyclopropylcetoesters. Ces derniers sont prepares a partir de sels de triphenylphosphonium, precurseurs de derives cyclopropaniques. La reactivite de ces composes cyclopropaniques vis a vis de nucleophiles varies est etudiee. L'action des amines primaires permet d'obtenir des pyrrolines. Une etude biologique montre l'activite biocide des composes prepares
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Jallet, Valérie. "Masquage de charges cationiques d'une polybase globulaire bifonctionnelle en vue de minimiser sa toxicité vis-à-vis du sang". Rouen, 1994. http://www.theses.fr/1994ROUES009.
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Cette thèse a pour objectif la diminution de la toxicité sanguine d'une polybase globulaire bifonctionnelle Q-P(TDAE)X, servant à vectoriser des principes actifs peu solubles dans l'eau. Pour cela, l'interaction de type polyanion-polycation avec des composés polyanioniques a été envisagée pour masquer tout ou une partie des charges électrostatiques ammonium quaternaire à la surface du globule. Une autre approche a consisté à modifier chimiquement les unités latérales amine tertiaire de l'homopolymère P(TDAE) en conservant l'hydrophilie du système. L'ensemble de ce travail est décrit en quatre chapitres. Dans le premier chapitre, l'héparine a été choisie, en raison de ses propriétés anticoagulantes, pour interagir avec la polybase globulaire. Le second chapitre présente l'influence de paramètres liés à des polyanions monofonctionnels sur la composition et la taille des particules de complexe. Dans le troisième chapitre, l'homopolymère P(TDAE) a été modifié chimiquement, soit par tentative de couplage d'oligomères de poly(éthylène glycol) sur les fonctions amine tertiaire de P(TDAE), soit par synthèse de polyzwitterions à partir de P(TDAE) et de 1,3-propane-sultone. Enfin, le dernier chapitre concerne l'étude du complexe formé entre la polybase globulaire et un copolymère poly(aspartate de sodium-b-éthylène glycol) et de sa toxicité par voie intra-veineuse.
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Bahri, Hamed. "Thermodynamique dans les milieux diphasés dispersés : cas des solutions micellaires et des microémulsions". Paris 6, 1986. http://www.theses.fr/1986PA066280.
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Déduction de relations théoriques générales liant dans les systèmes liquides diphasés, les grandeurs observables "globales" aux grandeurs "locales" dans les différentes phases. Exposé de définitions et de notions thermodynamiques. Etablissement de relations générales pour les grandeurs molaires partielles. Etudes du cas d'un système réel : bromures d'alkyltrimethylammonium en milieu eau-kcl, qui montre que les solutions micellaires en milieu salin concentré peuvent être considérées comme un système diphasé. Données sur le partage d'un soluté moléculaire aniline en milieu micellaire. Etudes des volumes molaires partiels des constituants d'une microémulsion, etc. . .
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Tiong, Erica. "Stereoselective formation of all carbon quaternary centers: synthesis of alpha,alpha-disubstituted beta-amino carbonyl compounds via the Mannich reaction and total synthesis of (-)-puraquinonic acid". Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=104585.
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A bicyclic thioglycolate lactam chiral auxiliary was previously developed in our group for the asymmetric formation of quaternary carbon stereocenters via enolate alkylation. This method is notable for the stereocontrolled generation of alpha, alpha-disubstituted amide enolates, without reliance on the steric differences of the alpha-substituents. Coupled with excellent facial discrimination in electrophilic approach, this led to a general and practical method for enantioselective preparation of quaternary carbon centers via alkylation reactions. This thesis describes the extension of this methodology to the stereoselective formation of alpha, alpha-disubstituted beta-amino carbonyl compounds via the Mannich reaction and also the application of the alkylation method to the total synthesis of (-)-puraquinonic acid.alpha,alpha-Disubstituted lithium enolates, stereoselectively generated from alpha,alpha-disubstituted bicyclic thioglycolate lactams, undergo Mannich addition to benzenesulfonyl imines to form beta-amino acid derivatives with high yield and diastereoselectivity. The reaction is general for a number of aromatic imines, including those with electron rich and electron poor substituents, heteroaromatic, and alpha, beta-unsaturated imines. alpha-Substituents on the amide enolate can be varied to include methyl, ethyl, propyl, benzyl, and allyl groups. The addition occurs via a closed Zimmerman-Traxler transition state with anti/syn relationships controlled by enolate geometry. Methods for N-deprotection and removal of the auxiliary to afford beta-amino acids and alcohols are described. A concise synthesis of (-)-puraquinonic acid is accomplished using the bicyclic lactam chiral auxiliary to set the lone quaternary center at an early stage. A tandem ring-closing cross metathesis process followed by Diels-Alder cycloaddition generates a dihydroindene, which makes up the bicyclic system of puraquinonic acid. The central quinone is formed by a Curtius rearrangement/Fremy's salt oxidation sequence. Upon completion, the auxiliary is removed via acidic hydrolysis to give the required carboxylic acid functionality. The synthesis is completed in 14 steps from commercially available lactam in 21% overall yield, and represents a 24 step improvement over the previous asymmetric synthesis.Un auxiliaire chiral de type lactame thioglycolate bicyclique permettant la formation de carbones asymétriques quaternaires via une alkylation d'énolates fut développé précédemment par notre groupe de recherche. Cette méthode est remarquable puisqu'elle permet la génération stéréocontrôlée d'énolates d'amide alpha, alpha-disubstitués, sans égard à la différence stérique entre les substituants alpha Démontrant également une excellente discrimination faciale lors de l'approche de l'électrophile, ce protocole est maintenant devenu une méthode générale et pratique pour la préparation énantiosélective de carbones quaternaires par alkylation. Cette thèse rapporte l'application de cette méthode à la formation stéréosélective de composés beta-amino carbonyles alpha, alpha-disubstitués via la réaction de Mannich, ainsi que son utilisation dans la synthèse totale de l'acide (-)-puraquinonique.Les énolates alpha, alpha-disubstitués de lithium, générés de façon stéréosélective à partir de lactames thioglycolates bicycliques alpha, alpha-disubstituées, réagissent avec des imines benzènesulfoniques pour créer des acides beta-aminés avec grande efficacité et diastéréosélectivité. La réaction est générale pour une panoplie d'imines aromatiques, incluant celles comportant des substituants pauvres en électrons, riches en électrons, hétéroaromatiques, ainsi que des imines alpha, beta-insaturées. Les substituants alphades énolates d'amides peuvent être des groupements méthyle, éthyle, propyle benzyle et allyle. L'addition emploie un état de transition de type Zimmerman-Traxler où la géométrie de l'énolate contrôle le ratio d'addition anti/syn. Des méthodes de déprotection du groupe amino libérant des acides beta-aminés et des alcools sont décrites.Une courte synthèse de l'acide (-)-puraquinonique a été réalisée en utilisant l'auxiliaire chiral de type lactame thioglycolate bicyclique pour créer l'unique centre quaternaire présent tôt dans la séquence. Par la suite, un processus tandem fermeture de cycle par métathèse - cycloaddition de Diels-Alder produit un dihydroindene constituant le sytème bicyclique de l'acide puraquinonique. La quinone centrale est formée via une séquence comprenant un réarrangement de Curtius et une oxydation par le sel de Fremy. Lorsque la synthèse est complétée, l'auxiliaire est enlevé par une hydrolyse acide, révélant la fonctionnalité acide carboxylique nécessaire. La synthèse est complétée avec un rendement de 21 % à partir d'une lactame commercialement disponible, et ce, en 14 étapes. Cette synthèse représente donc une amélioration de 24 étapes par rapport à la synthèse asymétrique précédente.
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Lee, Myung Jae. "Adsorption of Alkaline Copper Quat Components in Wood-mechanisms and Influencing Factors". Thesis, 2011. http://hdl.handle.net/1807/29788.
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Mechanisms of adsorption of alkaline copper quat (ACQ) components in wood were investigated with emphasis on: copper chemisorption, copper physisorption, and quat adsorption. Various factors were investigated that could affect the adsorption of individual ACQ components in red pine wood. Copper chemisorption in wood was affected by ligand types coordinating with Cu and the stability of the Cu-ligand complexes in solution. For Cu-monoethanolamine (Cu-Mea) system, the prevailing active solvent species at the solution pH, [Cu(Mea)2-H]+ complexes with wood acid sites and loses one Mea molecule through a ligand exchange reaction. The amount of adsorbed Cu was closely related to the cation exchange capacity of wood. An increase in Mea/Cu ratio increased the proportion of the uncharged Cu-Mea complex and resulted in decreased Cu chemisorption in wood. Copper precipitation is also an important Cu fixation mechanisms of Cu-amine treated wood. X-ray diffraction analysis revealed that in vitro precipitated Cu was a mixture of copper carbonates (azurite and malachite) and possibly Cu2O. Higher concentration Cu-amine solutions retarded the Cu precipitation to a lower pH because of higher free amine in the preservative-wood system. The changes in zeta potential of wood in relationship to the quaternary ammonium (alkyldimethylbenzylammonium chloride: ADBAC) adsorption isotherm showed two different adsorption mechanisms for quat in wood: ion exchange reaction at low concentration and additional aggregation form of adsorption by hydrophobic interaction at high concentration. Because of the aggregation effect, when wood was treated with ACQ, high amounts of ADBAC were concentrated near the surface creating a steep gradient with depth. This aggregated ADBAC was easily leached out while the ion exchanged ADBAC had high leaching resistance. Free Mea and Cu of ACQ components appeared to compete with ADBAC for the same bonding sites in wood.
Actas de conferencias sobre el tema "Quaternary amine compound"
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Patel, Arvind D. "Design and Development of Quaternary Amine Compounds: Shale Inhibition With Improved Environmental Profile". En SPE International Symposium on Oilfield Chemistry. Society of Petroleum Engineers, 2009. http://dx.doi.org/10.2118/121737-ms.
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Tiwari, Laxmikant. "Design & Development of Quaternary Amine Compounds: Corrosion Inhibitors with Improved Environmental Profiles". En SPE International Symposium on Oilfield Corrosion. Society of Petroleum Engineers, 2005. http://dx.doi.org/10.2118/95081-ms.
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Ng, Jun Hong Clarence, Tariq Almubarak y Hisham A. Nasr-El-Din. "Seed Extracts as Natural, Green, Non-Toxic Corrosion Inhibitors". En SPE Trinidad and Tobago Section Energy Resources Conference. SPE, 2021. http://dx.doi.org/10.2118/200935-ms.
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Abstract Acid treatments are commonly used in the oilfield to remove inorganic scale or to stimulate formatio ns. These treatments typically consist of using hydrochloric acid (HCl), acetic acid, formic acid, or chelating agents. At elevated temperatures, these acids are highly corrosive and can cause severe damage to tubulars as well as downhole equipment. To reduce damage from these acids, corrosion inhibitors are added to the treatment solution. Corrosion inhibitors used in the oil and gas industry are typically quaternary amines or sulfur-containing compounds. These compounds adsorb to the surface of the metal, thereby reducing contact between the metal surface and the corrosive substance. However, these corrosion inhibitors are damaging to the environment and harmful to human health. Alternative new environmentally-friendly corrosion inhibitors are also either toxic to the human body or face performance limitations at higher temperature field applications. To develop new environmentally friendly and non-toxic corrosion inhibitors for high-temperature applications, 15 edible seeds were tested as alternative sources of corrosion inhibitors. In order to determine the inhibition effect of 15 different seeds, N-80 and S13Cr coupons were exposed to 15 wt.% HCl solutions at temperatures between 77-250°F with 2 wt.% of grounded seed added for 6 hours. In addition, a control solution containing no corrosion inhibitor was used to establish a corrosion rate for a base case. This paper will show the results of such seeds and attempt to provide an awareness of natural seeds extract for use as corrosion inhibitors in conjunction with well acid treatments. It was noted that out of the 15 seeds, seeds 1 and 2 were found to perform the best at these conditions, exhibiting more than 90% corrosion inhibition efficiency. Seed 4 was observed to perform the worst, exhibiting only 16.8% inhibition efficiency. At 150°F, 2 wt.% of seeds 1 and 2 were tested with seed 1 achieving a corrosion rate of 0.00253 lb/ft2 while seed 2 was unable to provide sufficient inhibition with a corrosion rate of 0.153 lb/ft2. The control solution was found to have a corrosion rate of 0.371 lb/ft2 over the 6 hours at 150°F. Seed 1 was further tested at 200°F with the addition of corrosion inhibitor intensifiers and resulted in a corrosion rate of 0.00087 lb/ft2, while at 250°F, a corrosion rate of 0.00811 lb/ft2 was observed. The tests using S13Cr also showed that seed 1 worked well as a corrosion inhibitor for CRAs. The thermal degradation of seed 1 was also examined using NMR. These results show a new naturally occurring, green, non-toxic, high-temperature applicable corrosion inhibitor that can be developed from edible seeds.