Artículos de revistas: "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.

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Nicholas, Darrel. "Performance of waterborne copper/organic wood preservatives in an AWPA E14 soft-rot laboratory soil bed test using modified soil". Holzforschung 71, n.º 9 (28 de agosto de 2017): 759–63. http://dx.doi.org/10.1515/hf-2016-0230.

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AbstractSoil chemistry is known to have a major effect on the degradation of treated wood by basidiomycete fungi in laboratory and exterior ground-contact exposures. However, this topic received little attention from a soft-rot (SR) decay perspective. In the present paper, laboratory SR tests were performed with two different types of forest soils, which were also modified. Test samples, made ofPinus glabra(Walt.) (pine) were treated with four commercial copper/organic waterborne preservatives. In addition, soluble or particulate copper and the organic co-biocides quarternary ammonia compound or tebuconazole, were individually examined. After 19 months of soil bed exposure, moderate to severe degradation was observed in all treated samples in both soils. Surprisingly, microscopic examination showed minimal SR decay. Samples in the neutral soil had extensive tunneling bacterial deterioration and the best performance was observed with both copper/quaternary commercial formulations. Samples in the acidic soil appeared to have some white-rot and bacterial deterioration and all four commercial copper/organic formulations showed good statistically equivalent efficacy. For samples treated with only copper, the particulate copper samples performed statistically equivalent or slightly better than amine copper, while samples treated with only the organic quarternary or tebuconazole performed poorly in both soils.

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Bernhardt, PV, LS Curtis, NF Curtis, GA Lawrance, BW Skelton y AH White. "Condensations of Ethane-1,2-Diamine, Formaldehyde and Ammonia (or Nitroethane) Directed by Nickel(II) or Copper(II). Crystal Structure of (8-Methyl-8-nitro-1,3,6,10,13,15-hexaazatricyclo[13.1.1.1 13,15]octadecane)nickel(II) Perchlorate". Australian Journal of Chemistry 42, n.º 6 (1989): 797. http://dx.doi.org/10.1071/ch9890797.

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Both nickel(II) and copper(II) complexes of the sterically hindered linear tetraamines 1,3,5,7-tetra-azabicyclo [3.3.l]nonane-3,7-bis( ethanamine (4) and 3,3′-(ethane-1,2-diyl)bis(1,3,5,7-tetraaza-bicyclo [3.3.1] nonane (7) have been prepared from reaction of ethane-1,2-diamine complexes with formaldehyde and ammonia or by reaction of the metal salt with the quaternary 'hexamminium' cation (8) and ammonia, respectively. Spectroscopic properties and kinetics of the acid hydrolyses of these complexes are reported. Observed pseudo-first-order rate constants are of the order of 10-1 s-1 at 25° in 1 mol dm-3 HCl/NaCl; acid dependencies are reported. In addition to (4), a further acid-stable and presumably macrocyclic compound could be produced from reaction of [cu(en)2]2+ with formaldehyde and ammonia, assigned tentatively as (9). Further reaction of the nickel(II) complex of (4) with formaldehyde and nitroethane yielded the macrocyclic complex of (10), which was characterized by a crystal structure analysis. Reduction with zinc amalgam yielded an amine-substituted macrocyclic complex from the nitro-substituted precursor. The title complex [Ni(10)](ClO4)2.H2O crystallized in the space group P21/n, a 14.367(2), b 13.099(2), c 12.325(3) � , β 101.01(1)�. The nickel(II) was located in a square plane of two secondary (Ni-N 1.92 � ) and two tertiary nitrogens (Ni-N 1.93 � ); the 'football' formed as one cap from ammonia and formaldehyde condensation was clearly defined.

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Christoffers, Jens, Wolfgang Frey, Heiko Scharl y Angelika Baro. "Absolute Konfiguration von (+)-1,2,3,4,6,7,8,8a-Octahydro-6-isochinolon- 8a-carbonsäuremethylester und die Stereochemie einer Kupfer-katalysierten asymmetrischen Michael-Reaktion / Absolute Configuration of Methyl (+)-1,2,3,4,6,7,8,8a-Octahydro-6-isoquinolone-8a-carboxylate and Stereochemistry of a Copper-Catalyzed Asymmetric Michael Reaction". Zeitschrift für Naturforschung B 59, n.º 4 (1 de abril de 2004): 375–79. http://dx.doi.org/10.1515/znb-2004-0404.

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AbstractEnantiopure Boc-protected piperidine derivative (+)-5c, with a quaternary stereocenter, was obtained by copper-catalyzed, L-valine diethylamide-mediated Michael reaction. For determination of the absolute configuration, 5c was derivatized by cyclization with pyrrolidine/AcOH to give compound 6 with bicyclo[4.4.0]-constitution, deprotection of the amino function with TFA and subsequent reaction with 2-iodobenzoic acid to yield the crystalline bicyclic amide 7. X-ray crystallographic analysis confirmed the constitution of compounds 5c and 6 and established the (R) configuration of 7. Thus, starting Michael addition product (+)-5c has to be (S) configured, because an epimerization at the quaternary stereocenter is excluded. This result is in accordance with our working model of the Cu-catalyzed, auxiliary-assisted Michael reaction.

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Wargo, Matthew J. y Deborah A. Hogan. "Identification of genes required for Pseudomonas aeruginosa carnitine catabolism". Microbiology 155, n.º 7 (1 de julio de 2009): 2411–19. http://dx.doi.org/10.1099/mic.0.028787-0.

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Carnitine is a quaternary amine compound prevalent in animal tissues, and a potential carbon, nitrogen and energy source for pathogens during infection. Characterization of activities in Pseudomonas aeruginosa cell lysates has previously shown that carnitine is converted to 3-dehydrocarnitine (3-dhc) which is in turn metabolized to glycine betaine (GB), an intermediate metabolite in the catabolism of carnitine to glycine. However, the identities of the enzymes required for carnitine catabolism were not known. We used a genetic screen of the P. aeruginosa PA14 transposon mutant library to identify genes required for growth on carnitine. We identified two genomic regions and their adjacent transcriptional regulators that are required for carnitine catabolism. The PA5388–PA5384 region contains the predicted P. aeruginosa carnitine dehydrogenase homologue along with other genes required for growth on carnitine. The second region identified, PA1999–PA2000, encodes the α and β subunits of a predicted 3-ketoacid CoA-transferase, an enzymic activity hypothesized to be involved in the first step of deacetylation of 3-dhc. Furthermore, we confirmed that an intact GB catabolic pathway is required for growth on carnitine. The PA5389 and PA1998 transcription factors are required for growth on carnitine. PA5389 is required for induction of the PA5388–PA5384 transcripts in response to carnitine, and the PA1999–PA2000 transcripts are induced in a PA1998-dependent manner and induction appears to depend on a carnitine catabolite, possibly 3-dhc. These results provide important insight into elements required for carnitine catabolism in P. aeruginosa and probably in other bacteria.

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Bohnert, Sabine y Wolf-H. Gündel. "[1.4]Diazepino[6.5-c]chinoline mit L-Aminosäurebaustein — Darstellung und Reaktionen / [1.4]Diazepino[6.5-c]quinolines with L-Amino Acid Moiety — Preparation and Reactions". Zeitschrift für Naturforschung B 42, n.º 9 (1 de septiembre de 1987): 1167–73. http://dx.doi.org/10.1515/znb-1987-0918.

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Quaternary salts of the amides of N-(3-quinolinecarbonyl)-N-alkyl-amino acids (6) cyclise under the influence of base to the title compounds (7). This intramolecular addition is a reaction with high diastereoselectivity, dependent on the amino acid part. 7 disproportionates to 8 and 9. 7 behaves as lipophilic NAD model compound in the reaction with 2-propanol under ZnCl2 catalysis.

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Dinarvand, Mojdeh y Malcolm Spain. "Identification of Bioactive Compounds from Marine Natural Products and Exploration of Structure-Activity Relationships (SAR)". Antibiotics 10, n.º 3 (22 de marzo de 2021): 337. http://dx.doi.org/10.3390/antibiotics10030337.

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Marine natural products (MNPs) have been an important and rich source for antimicrobial drug discovery and an effective alternative to control drug resistant infections. Herein, we report bioassay guided fractionation of marine extracts from sponges Lendenfeldia, Ircinia and Dysidea that led us to identify novel compounds with antimicrobial properties. Tertiary amines or quaternary amine salts: aniline 1, benzylamine 2, tertiary amine 3 and 4, and quaternary amine salt 5, along with three known compounds (6–8) were isolated from a crude extract and MeOH eluent marine extracts. The antibiotic activities of the compounds, and their isolation as natural products have not been reported before. Using tandem mass spectrometry (MS) analysis, potential structures of the bioactive fractions were assigned, leading to the hit validation of potential compounds through synthesis, and commercially available compounds. This method is a novel strategy to overcome insufficient quantities of pure material (NPs) for drug discovery and development which is a big challenge for pharmaceutical companies. The antibacterial screening of the marine extracts has shown several of the compounds exhibited potent in-vitro antibacterial activity, especially against methicillin-resistant Staphylococcus aureus (MRSA) with minimum inhibitory concentration (MIC) values between 15.6 to 62.5 microg mL−1. Herein, we also report structure activity relationships of a diverse range of commercial structurally similar compounds. The structure-activity relationships (SAR) results demonstrate that modification of the amines through linear chain length, and inclusion of aromatic rings, modifies the observed antimicrobial activity. Several commercially available compounds, which are structurally related to the discovered molecules, showed broad-spectrum antimicrobial activity against different test pathogens with a MIC range of 50 to 0.01 µM. The results of cross-referencing antimicrobial activity and cytotoxicity establish that these compounds are promising potential molecules, with a favourable therapeutic index for antimicrobial drug development. Additionally, the SAR studies show that simplified analogues of the isolated compounds have increased bioactivity.

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González, José. "Application of quaternary ammonium compound and aliphatic amine as biocides in the mitigation of microfouling adhered to the internal surface of heat exchangers condensers refrigerated by seawater. Impact on the efficiency of different control strategies applied". Journal of Marine Engineering & Technology 20, n.º 1 (11 de julio de 2019): 42–51. http://dx.doi.org/10.1080/20464177.2019.1639460.

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Holý, Antonín, Miloš Buděšínský, Jaroslav Podlaha y Ivana Císařová. "Synthesis of Quaternary 1-[2-(Phosphonomethoxy)ethyl] Derivatives of 2,4-Diaminopyrimidine and Related Acyclic Nucleotide Analogs". Collection of Czechoslovak Chemical Communications 64, n.º 2 (1999): 242–56. http://dx.doi.org/10.1135/cccc19990242.

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Quaternization of 2,4-diaminopyrimidine (2) by diisopropyl 2-chloroethoxymethanephosphonate (3) followed by bromotrimethylsilane treatment and subsequent hydrolysis gave zwitterionic N1-[2-(phosphonomethoxy)ethyl] derivative, hydrogen {[2-(2,4-diaminopyrimidin-1-io)ethoxy]methyl}phosphonate (5). Its structure was confirmed by X-ray crystallography. The same product was obtained from 2-amino-4-[(dimethylaminomethylene)amino]pyrimidine (6) by an analogous reaction sequence followed by an aqueous ammonia treatment after the transsilylation reaction. Also the quaternizations of 4,6-diaminopyrimidine (7) and 2,4,6-triaminopyrimidine (8) with the halo derivative 3 afforded the zwitterionic N1-substituted compounds 9 and 10, respectively. In contrast to this regiospecific reaction, 2-aminopyrimidine (11) gave on treatment with compound 3 and following deprotection the exo-N2-isomer 13. This compound was also obtained by the reaction starting from 2-[(dimethylaminomethylene)amino]pyrimidine (12) which was prepared by treatment of compound 11 with dimethylformamide dineopentyl acetal. Also 2,3-diaminopyridine (14) gave by the above reaction a mixture of 2-amino-3-{[2-(phosphonomethoxy)ethyl]amino}pyridine (15) and quaternary N1-[2-(phosphonomethoxy)ethyl] derivative (16). None of these analogs of the antiviral PMEDAP exhibited any antiviral activity against DNA viruses or retroviruses, nor any cytostatic activity.

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Novikov, Andrei, Ekaterina Blinova, Elena Semeleva, Karina Karakhanjan, Mikhail Mironov, Dmirty Blinov, Yuliya Krainova, Dmitry Pakhomov, Olga Vasilkina y Elena Samishina. "On local anesthetic action of some dimethylacetamide compounds". Research Results in Pharmacology 4, n.º 4 (2 de diciembre de 2018): 1–8. http://dx.doi.org/10.3897/rrpharmacology.4.31440.

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The study aim was to explore local anesthetic properties of some tertiary and quaternary derivatives of dimethylacetamide. Materials and methods. The study was performed on white laboratory mice and rats of both sexes, male Agouti guinea pigs, and isolated sciatic nerves of lake frog. In the focus of the study there were two quaternary and eight tertiary compounds of dimethylacetamide with substituted anion with some amino and carbonic acids residue. A local anesthetic property was predicted by computational analysis. Acute toxicity of the most promising substances was studied in mice through subcutaneous route. Local anesthetic activity of tertiary compounds LKhT-3-00, LKhT-4-00 and quaternary LKhT-12-02 was studied on models of terminal, infiltration and conduction anesthesia. The influence of substances on mixed nerve conduction was investigated on lake frog’s isolated sciatic nerves. Results and discussion. The greatest probability of the local anesthetic activity during computational analysis was estimated for the tertiary derivatives of dimethylacetamide LKhT-3-00 and LKhT-4-00 and for the quaternary compound LKhT-12-02. According to their toxicological profile, the compounds belong to moderately toxic substances (class 3). On the model of terminal and infiltration anesthesia, substances LKhT-3-00 and LKhT-4-00 at concentrations of 0.5-1% rapidly cause deep and prolonged anesthesia. On the models of conduction anesthesia, the quaternary derivative of dimethylacetamide LKhT-12-02 has the greatest analgesic effect. The duration of the effect of the substance is over 3 hours. All the investigated compounds block sciatic nerve conduction. The longest effect is registered for LKhT-12-02. Conclusions. Dimethylacetamide derivatives at concentrations of 0.5-1.0% exhibit a local anesthetic activity, and are effective for terminal, conduction and infiltration anesthesia. Their effect is due to blockade of nerve conduction.

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20

Kuczera, J., S. Witek, T. E. Kral, J. Hładyszowski, J. Łuczyński y S. Przestalski. "Influence of Some Lysosomotropic Compounds on Calcium Ion Desorption Process from Liposome Membrane". Zeitschrift für Naturforschung C 53, n.º 5-6 (1 de junio de 1998): 389–97. http://dx.doi.org/10.1515/znc-1998-5-614.

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The effect of a group of model lysosomotropic compounds on the process of Ca2+ ion desorption from lecithin liposome membranes was studied. The compounds studied were: hydrochlorides of fatty acids 2-dimethylaminoethyl esters (DM-n) for n = 9, 11, 13 and 15 carbon atoms in the fatty acid alkyl chain and methochloride of 2-dimethylaminoethyl laurate (DMS-11). It was found that all the compounds studied caused increased desorption with increasing concentration of the compound. Most effective was the quaternary ammonium salt, DMS-11. Moreover, it was found that the process of Ca2+ desorption from the membrane depended on pH of the medium. Compound DM-11 was more active at pH 8 than at pH 5. The action of DM-n compounds depended on the alkyl chain length, DM-11 and DM-13 being the most active. Apparently free amines penetrate the phospholipid membranes and incorporate into its hydrophobic core causing structural deformations. Hydrochlorides of fatty acids and the quaternary ammonium salt induce desorption of calcium ions mostly as a result of competitive electrostatic interactions. By quantum chemistry, PM3 method, and methods of molecular modelling we established the higher hydrophilicity of the polar head of DM-n series with respect to the polar head of the DMS-n compounds. DM-n compounds possess both acceptor and donor properties for hydrogen bonding while DMS-n are instrumental as acceptors only. It should be noted, that the results obtained in this paper for model membranes are in accordance with those for biological ones.

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21

Zhang, Lin Xia, Tao Liu y Ai Qin Luo. "Application of Quaternary Aminated β-Cyclodextrin Ionic Liquid Stationary Phase in Capillary Gas Chromatography". Advanced Materials Research 317-319 (agosto de 2011): 1936–39. http://dx.doi.org/10.4028/www.scientific.net/amr.317-319.1936.

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Two kinds of quaternary aminated β-cyclodextrin ionic liquids were synthesized and used as stationary phases in capillary gas chromatography. The influences of different counter ions (tetra- borofluoride, bis-trifluoromethanesulfonylimide) were studied. The results indicated that quaternary aminated β-cyclodextrin ionic liquids possessed good column coating properties and a chromatographic separation abilities. The Grobs mixture, alkanes, alcohols and aromatic position isomers, such as xylene, nitrotoluene, dichlorobenzene and cresol were separated well. These quaternary aminated β-cyclodextrin ionic liquids have potential to separate some complex compounds including alcohol, amine, ester etc.

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22

Sheverdov, Vladimir Р., Vera Davydova, Oleg Nasakin, Maksim Mar’yasov y Olga Lodochnikova. "Ethene-1,1,2,2-tetracarbonitrile and Methanol in the Methylating Reaction of Tertiary Amines to the Quaternary Ammonium Compounds of 1,1-Dicyano-2-methoxy-2-oxoethane-1-ide". Synlett 30, n.º 02 (7 de diciembre de 2018): 173–77. http://dx.doi.org/10.1055/s-0037-1610343.

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We discovered a new method to methylate tertiary amines such as urotropine, triethylamine, pyridine, 2-methylpyridine, 4-acetylpyridine, and isonicotinamide, up to quaternary ammonium compounds, with 1,1-dicyano-2-methoxy-2-oxoethane-1-ide being the counterion. Methyl-1,3,5,7-tetraazaadamantan-1-ium 1,1-dicyano-2-methoxy-2-oxoethane-1-ide, N,N-diethyl-N-methylethanaminium 1,1-dicyano-2-methoxy-2-oxoethane-1-ide, and substituted-methylpyridinium 1,1-dicyano-2-methoxy-2-oxoethane-1-ides were synthesized. Quaternary ammonium compounds of 1,1-dicyano-2-methoxy-2-oxothane-1-ide were synthesized within a single stage by stirring methanol solutions of tertiary amines with ethene-1,1,2,2-tetracarbonitrile (ETCN) at room temperature. In the reaction of ETCN with tertiary amines in methanol, processes occur that form the 1,1-dicyano-2-methoxy-2-oxoethane-1-ide fragment with simultaneous N-methylation. Crystal structures based on X-ray diffraction analysis of the obtained compounds were studied.

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23

Potikha, Lyudmyla M., Volodymyr V. Sypchenko y Valentyn I. Davydov. "Reactions of [2-(Bromomethyl)phenyl](4-chlorophenyl)methanone: A New Synthesis of [1,3]Thiazolo[3,2-b][2,4]benzodiazepine, Benzimidazo[1,2-b][2,4]benzodiazepine and Benzimidazo[1,2-b][2]benzazepine Derivatives". French-Ukrainian Journal of Chemistry 7, n.º 1 (2019): 96–103. http://dx.doi.org/10.17721/fujcv7i1p96-103.

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A new approach to the development of a number of azolo-condensed azepines and diazepines has been proposed. The method for the synthesis of [1,3]thiazolo[3,2-b][2,4]benzodiazepine, benzimidazo[1,2-b][2,4]benzodiazepineandbenzimidazo[1,2-b][2]benzazepinederivatives involves the reaction of [2-(bromomethyl)phenyl](4-chlorophenyl)methanonewith5-methyl-1,3-thiazol-2-amine, 1H-benzimidazol-2-amineand1,2-dimethyl-1H-benzimidazole. The formation of the quaternary salt of the initial diazole has been done under mild conditions in MeCN. The following intramolecular condensation has been realized by heating 2-amino azolium salts in AcOH or in Et3N as in the case of 2-methyl azolium salt. The structures of these cyclic compounds have been confirmed by mass spectrometry measurements, elemental analysis and NMR spectra.

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24

Johnson, Stuart, Ervin Kovács y Michael F. Greaney. "Arylation and alkenylation of activated alkyl halides using sulfonamides". Chemical Communications 56, n.º 21 (2020): 3222–24. http://dx.doi.org/10.1039/d0cc00220h.

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25

López-de-Luzuriaga, José M., Marcus Söldner, Annette Schier y Hubert Schmidbaur. "Gold(I) Complexes of Open-chain and Cyclic Di-secondary Amines". Zeitschrift für Naturforschung B 52, n.º 2 (1 de febrero de 1997): 209–13. http://dx.doi.org/10.1515/znb-1997-0211.

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Abstract Treatment of N,N′-diisopropyl-ethylenediamine or 1,4-piperazine with two equivalents of [(Ph3P)Au]+ BF4- leads to binuclear complexes of the diamines: {[(Ph3P)Au]HN(iPro)NCH2-}22+ 2 BF4- (1) and {[(Ph3P)Au]HNCH2CH2}22+ 2 BF4- (2), respectively. In the products each quaternary ammonium center bears one gold ligand, one hydrogen atom and two alkyl substituents. The crystal structures of both compounds have been determined. Compound 1 contains discrete ion-triples. The ethylene bridge in the dications is in an unfolded conformation, with a crystallographic center of inversion, and allows for weak hydrogen bonding N-H--F [2.085 Å; N-H--F 169.2°] between the NH functions and the counterions. The existing distant contacts F--Au [3.599 Å] are probably less significant for the aggregation of the ion triples, but will contribute through Coulomb forces. Compound 2 crystallizes with two solvent molecules CH2CI2. The dication has a crystallographic center of inversion with the piperazine ring in a chair conformation and the gold atoms in equatorial positions. There are hydrogen bonds N-H--F [2.076 and 2.457 Å] between the dication and the anions which lead to the formation of ion-triples, with further contacts between the BF4- anions and the solvent molecules [C-H--F 2.340 and 2.446 Å].

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26

Shamsuri, Ahmad Adlie y Siti Nurul Ain Md Jamil. "Application of Quaternary Ammonium Compounds as Compatibilizers for Polymer Blends and Polymer Composites—A Concise Review". Applied Sciences 11, n.º 7 (2 de abril de 2021): 3167. http://dx.doi.org/10.3390/app11073167.

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A wide variety of quaternary ammonium compounds (QACs) have escalated the attraction of researchers to explore the application of QACs. The compounds have frequently been synthesized through alkylation or quaternization of tertiary amines with alkyl halides. Recently, QACs have been applied to compatibilize polymer blends and polymer composites in improving their thermo-mechanical properties. This concise review concentrates on the application of two types of QACs as compatibilizers for polymer blends and polymer composites. The types of QACs that were effectively applied in the blends and composites are quaternary ammonium surfactants (QASs) and quaternary ammonium ionic liquids (QAILs). They have been chosen for the discussion because of their unique chemical structure which can interact with the polymer blend and composite components. The influence of QASs and QAILs on the thermo-mechanical properties of the polymer blends and polymer composites is also described. This review could be helpful for the polymer blend and polymer composite researchers and induce more novel ideas in this research area.

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27

Shakhmaev, Rinat N., Alisa Sh Sunagatullina y Vladimir V. Zorin. "ISOMERS OF 3-CHLORO-N,N,N-TRIS(3-METHYLBUTYL)PROP-2-EN-1-AMMINIUM CHLORIDE AS COMPLEX OIL AND GAS FIELD REAGENTS WITH ANTIHYDRATE, ANTICORROSIVE AND BACTERICIDAL ACTION". IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENII KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA 63, n.º 6 (13 de mayo de 2020): 80–84. http://dx.doi.org/10.6060/ivkkt.20206306.5969.

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One of the most promising classes of low-dosage hydrate inhibitors is anti-agglomerants, which are favorably characterized by high efficacy at very low working concentrations (0.1-0.5%). We have investigated the possibility of creating new anti-agglomerants with enhanced anticorrosive and bactericidal properties based on the quaternization of tris(3-methylbutyl)amine with (E)- and (Z)-1,3-dichloropropene isomers. It is well known that compounds with a 3-chloroprop-2-enyl fragment have a pronounced anticorrosive and bactericidal action. Thus, the presence in the quaternization products of isopentyl groups and 3-chloroprop-2-enyl fragments that are optimal for preventing agglomeration of the gas hydrates can contribute to the complex antihydrate, anticorrosive and bactericidal activity of these compounds. An attempt to conduct the alkylation of tris(3-methylbutyl)amine with (E)-1,3-dichloropropene in standard solvent – boiling ethanol for 3 days leads to a low yield of the target quaternary salt. Using chromatography-mass spectrometry, it was established that there are significant amounts of by-products in the reaction mixture, which are formed as a result of various nucleophilic substitutions and elimination reactions. Alkylation of tris(3-methylbutyl)amine in boiling acetonitrile proceeds faster and more selectively in 80% yield of (E)-3-chloro-N,N,N-tris(3-methylbutyl)prop-2-en-1-amminium chloride in 20 h. A quaternization with (Z)-1,3-dichlopropene under the same conditions gives an isomeric quaternary salt with a similar yield. The alkylation of tris(3-methylbutyl)amine with isomers of 1,3-dichloropropene proceeds without allyl rearrangement and with full retention of the configuration of the chlorovinyl fragment. The structure and purity of the obtained compounds was unambiguously confirmed by NMR spectroscopy data. Tests in rocking cells using tetrahydrofuran-water model systems (forming the structure sII similar to natural gas hydrates), gravimetric and microbiological methods showed high antihydrate, anticorrosive and bactericidal efficiency of the obtained compounds in concentrations of 0.5%.

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Meijide, Francisco, María Pilar Vázquez-Tato, Julio Seijas, Santiago de Frutos, Juan V. Trillo Novo, Victor H. H. Soto y José Vázquez Tato. "Crystal Structure of a Cationic Bile Salt Derivative ([3,5,7,12]-3-(2-naphthyloylamino)-7,12-dihydroxycholan-24-triethylammonium iodide)". Crystals 9, n.º 3 (6 de marzo de 2019): 135. http://dx.doi.org/10.3390/cryst9030135.

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The crystal structure of the iodide salt of a quaternary ammonium derivative of cholic acid having a naphthalene group attached to the 3rd position of the steroid nucleus through an amide bond ([3,5,7,12]-3-(2-naphthyloylamino)-7,12-dihydroxycholan-24-triethylammonium iodide) has been resolved. The compound crystallizes in the P212121 orthorhombic space group (a/Å = 10.9458(3); b/Å = 12.1625(3); c/Å = 28.4706(7)). The lateral chain adopts a fully extended tttt conformation because the quaternary ammonium group cannot participate in the formation of hydrogen bonds. The iodide ion is involved in the formation of hydrogen bonds as well as the amide group and the two steroid hydroxy groups. Hirshfeld surface analysis confirms that these contacts, as well as the electrostatic interactions, stabilize the structure. The helixes around the 21 screw axis are right-handed ones.

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29

Bohnert, Sabine y Wolf-H. Gündel. "Redoxreaktionen mit cyclopeptidartigen Chinolinderivaten als lipophil-maskierte NAD-Modellverbindungen / Redox Reactions with Cyclopeptide-Like Quinoline Derivatives as Lipophilic NAD Model Compounds". Zeitschrift für Naturforschung B 42, n.º 9 (1 de septiembre de 1987): 1159–66. http://dx.doi.org/10.1515/znb-1987-0917.

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Quaternary salts of the amides of N-(3-quinolinecarbonyl) amino acids (7) cyclise under the influence of base to give fourteen membered rings (9). This dimerisation is a reaction with high diastereoselectivity. The addition product 9 can be regarded as lipophilic, masked NAD model compound: 9 oxidizes 2-propanol under ZnCl2 catalysis to give in high yield acetone and the 1.4-dihydroquinoline.

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30

Slavíková, Barbora, Alexander Kasal y Miloš Buděšínský. "Dihydrotestosterone with an Ammonium Centre in the Position 16β". Collection of Czechoslovak Chemical Communications 62, n.º 4 (1997): 656–64. http://dx.doi.org/10.1135/cccc19970656.

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In an alternative synthesis of 17β-hydroxy-16β-(piperidin-1-yl)-5α-androstan-3-one (4), neighbouring group participation between a 17β-carbonyloxy group and the 16β-amino group was used and a high yield partial hydrolysis of 3β,17β-diacetoxy-16β-(piperidin-1-yl)-5α-androstane (11) was developed. Interference of the neighbouring group participation was also apparent in another 17β-acetoxy derivative - in oxidation of compound 12 to 13. Compound 4 was converted into water-soluble derivatives, i.e. quaternary ammonium derivatives 17 to 20.

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31

Kula, Natalia, Edyta Mazurkiewicz y Ewa Obłąk. "Microorganisms and cationic surfactants". Postępy Higieny i Medycyny Doświadczalnej 74 (11 de diciembre de 2020): 556–65. http://dx.doi.org/10.5604/01.3001.0014.5776.

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Quaternary ammonium salts (QAS) as cationic surfactants with an amphiphilic structure show biocidal activity against non-pathogenic and pathogenic microorganisms (Gram-positive, Gram-negative bacteria, fungi, as well as lipophilic viruses) occurring in planktonic form or forming biofilms. They can also coat the surface of various materials (glass, metal, silicone, polyester) from which medical devices are made, such as: catheters, implants, heart valves, endoprostheses, and this allows inhibiting the adhesion of microorganisms to these surfaces. In their chemical structure, these surfactants contain labile bonds, e.g. ester or amide bonds, which enable the biodegradation of the compounds. Thanks to this, they are classified as “green chemistry”. Their biological activity depends on the length of the hydrophobic chain and the structure of the hydrophilic head of the compound. QAS have an affinity for the cell membrane by interacting with its lipids and proteins, which can lead to its disintegration. They have the ability to inhibit the activity of H+-ATPase of the cell membrane, the enzyme responsible for its electrochemical gradient and the transport of nutrients to the cell, e.g. amino acids. These compounds can influence the lipid composition (quantitative and qualitative) of the cell membrane of microorganisms. They are also inhibitors of respiratory processes and can induce the formation of reactive oxygen species. These surfactants are capable of forming micelles and liposomes in an aqueous environment. They are widely used in medicine (as disinfectants, DNA carriers in gene therapy), in industry and environmental protection (as biocides, preservatives) and in agriculture (as fungicides). The widespread use of QAS in many fields causes the growing resistance of microorganisms to these compounds. A common mechanism that generates reduced susceptibility to QAS is the presence of efflux pumps.

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32

Nazarova, Anastasia, Dmitriy Shurpik, Pavel Padnya, Timur Mukhametzyanov, Peter Cragg y Ivan Stoikov. "Self-Assembly of Supramolecular Architectures by the Effect of Amino Acid Residues of Quaternary Ammonium Pillar[5]arenes". International Journal of Molecular Sciences 21, n.º 19 (29 de septiembre de 2020): 7206. http://dx.doi.org/10.3390/ijms21197206.

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Novel water-soluble multifunctional pillar[5]arenes containing amide-ammonium-amino acid moiety were synthesized. The compounds demonstrated a superior ability to bind (1S)-(+)-10-camphorsulfonic acid (S-CSA) and methyl orange dye depending on the nature of the substituent, resulting in the formation one-to-one complexes with both guests. The formation of host-guest complexes was confirmed by ultraviolet (UV), circular dichroism (CD) and 1H NMR spectroscopy. This work demonstrates the first case of using S-CSA as a chiral template for the non-covalent self-assembly of architectures based on pillar[5]arenes. It was shown that pillar[5]arenes with glycine or L-alanine fragments formed aggregates with average hydrodynamic diameters (d) of 165 and 238 nm, respectively. It was established that the addition of S-CSA to the L-alanine-containing derivative led to the formation of micron-sized aggregates with d of 713 nm. This study may advance the design novel stereoselective catalysts and transmembrane amino acid channels.

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Liu, Danyang, Zhijian Zhou y Hao Liu. "The Theoretical Total Synthesis of an Aromatic Esters of the Crinane Amaryllidaceae Alkaloid Ambelline". E3S Web of Conferences 267 (2021): 02011. http://dx.doi.org/10.1051/e3sconf/202126702011.

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ABSTRACT. A series of crinane-type alkaloid ambelline derivatives were assessed for their potency to inhibit both acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE), which has been shown to be effective medicine for the treatment of Alzheimer’s disease. However, no enzyme modification has been reported total synthesis. In this work, two possible theoretical synthesis paths of Crinane-type alkaloid ambelline were discussed in this article. The major difficulty of the proposed synthesis was the synthesis of the quaternary carbon. One of the approaches emphasized on the reactions between cyclic and heterocyclic compounds and substrates on the intermediates to generate the quaternary carbon shown on the desired product. The other approach utilized series of amine reactions and Michael addition to create the precursor for the reactant in the Diels-Alder reaction and, therefore, the quaternary carbon, and finally, the desired natural product was obtained after a weak acid workup. The synthesis of ambelline has the potential to provide new pathways for treatment of Alzheimer’s disease.

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Kawanishi, Ryouta, Shinya Hattori, Seiji Iwasa y Kazutaka Shibatomi. "Amine-Catalyzed Decarboxylative Aldol Reaction of β-Ketocarboxylic Acids with Trifluoropyruvates". Molecules 24, n.º 15 (30 de julio de 2019): 2773. http://dx.doi.org/10.3390/molecules24152773.

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Decarboxylative aldol reaction of aliphatic carboxylic acids is a useful method for C–C bond formation because carboxylic acids are an easily available class of compounds. In this study, we found that the decarboxylative aldol reaction of tertiary β-ketocarboxylic acids and trifluoropyruvates proceeded smoothly to yield the corresponding aldol products in high yields and with high diastereoselectivity in the presence of a tertiary amine catalyst. In this reaction, we efficiently constructed a quaternary carbon center and an adjacent trifluoromethylated carbon center. This protocol was also extended to an enantioselective reaction with a chiral amine catalyst, and the desired product was obtained with up to 73% enantioselectivity.

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35

Cativiela, Carlos y Marı́a Dolores Dı́az-de-Villegas. "Stereoselective synthesis of quaternary α-amino acids. Part 2: Cyclic compounds". Tetrahedron: Asymmetry 11, n.º 3 (febrero de 2000): 645–732. http://dx.doi.org/10.1016/s0957-4166(99)00565-0.

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36

Cativiela, Carlos y Marı́a Dolores Dı́az-de-Villegas. "Stereoselective synthesis of quaternary α-amino acids. Part 1: Acyclic compounds". Tetrahedron: Asymmetry 9, n.º 20 (octubre de 1998): 3517–99. http://dx.doi.org/10.1016/s0957-4166(98)00391-7.

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SAITOH, HIROSHI, NORIKO HASEGAWA, SHINJI KAWAI, KATSUMI MIYAZAKI y TAKAICHI ARITA. "Interaction of tertiary amines and quaternary ammonium compounds with gastrointestinal mucin." Journal of Pharmacobio-Dynamics 9, n.º 12 (1986): 1008–14. http://dx.doi.org/10.1248/bpb1978.9.1008.

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38

Khunathai, Kanjana, Durga Parajuli, Keisuke Ohto, Hidetaka Kawakita, Hiroyuki Harada, Katsutoshi Inoue, Koichi Hirota y Masamitsu Funaoka. "Adsorption Behavior of Quaternary Amine Types of Lignophenol Compounds for Some Precious Metals". Solvent Extraction and Ion Exchange 28, n.º 3 (13 de abril de 2010): 403–14. http://dx.doi.org/10.1080/07366291003683735.

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39

Guo, Yong. "Analysis of Quaternary Amine Compounds by Hydrophilic Interaction Chromatography/Mass Spectrometry (HILIC/MS)". Journal of Liquid Chromatography & Related Technologies 28, n.º 4 (2 de julio de 2005): 497–512. http://dx.doi.org/10.1081/jlc-200047200.

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El-Shanawany, Mohamed A., Hanaa M. Sayed, Sabrin R. M. Ibrahim y Marwa A. A. Fayed. "New Nitrogenous Compounds from Anisotes trisulcus". Zeitschrift für Naturforschung C 69, n.º 5-6 (1 de junio de 2014): 209–18. http://dx.doi.org/10.5560/znc.2013-0116.

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Re-investigation of the methanolic extract of Anisotes trisulcus (Forssk.) Nees aerial parts led to the isolation of two new tricyclic quinazoline alkaloids, 8-amino-7,8,9,11-tetrahydro-6H-pyrido[2,1-b]- quinazoline-2,6-diol (4) and 8-amino-3,6-dihydroxy-7,8,9-trihydro-6H-pyrido[2,1-b]quinazoline- 11-one (5), and two quaternary ammonium compounds, (dimethylamino)-N-(hydroxymethyl)-N,Ndimethyl methanaminium chloride (6) and N-[(carboxyamino)methyl]-N,N-dimethyl ethanaminium chloride (7), together with three known compounds, peganine (1), vasicinone (2), and anisotine (3). The structures of these compounds were established on the basis of physical, chemical, and spectral data (UV, IR, MS, 1D and 2D NMR), as well as by comparison with authentic samples. GC-MS analysis of the fatty acid methyl esters and unsaponifiable matter revealed the presence of 46 fatty acids, 53 hydrocarbons, and 18 sterols. The different extracts were evaluated for their antihyperglycaemic activities. The MeOH, n-hexane, and EtOAc extracts exhibited a significant hypoglycaemic effect

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Korotkii, Y. V., N. A. Vrynchanu, M. L. Dronova, Z. S. Suvorova y O. A. Smertenko. "Synthesis, antibacterial and antifungal activity of 1-[4-(1,1,3,3-tetramethylbutyl)phenoxy]-3-dialkylamino-2-propanol quaternary salts". Farmatsevtychnyi zhurnal, n.º 1 (12 de febrero de 2019): 56–62. http://dx.doi.org/10.32352/0367-3057.1.15.04.

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The emergence and spread of resistant strains of pathogens as well as reduction of the efficacy of current antimicrobial agents requires the development of novel antimicrobial compounds. The aim of the present study was synthesis and evaluation of antimicrobial activity of new arylaliphatic aminopropanols. The objects of the present study were 1-[4-(1,1,3,3-tetramethylbutyl)phenoxy]-3-dialkylamino-2-propanol quaternary salts (compounds I–XIV). Compounds synthesis was carried out by heating of precursor epoxide and excessive amount of appropriate amines in isopropanole, followed by treatment with excess of alkyl halides. Methods of elemental analysis, IR- and PMR-spectroscopy were used for confirmation of chemical structure. Antimicrobial activity against Staphylococcus аureus АTCC 25923, Escherichia coli ATCC 25922, Pseudomonas aeruginosa АТСС 27853 and Candida albicans NCTC 885/653 was determined by a broth dilution method and evaluated via minimum inhibitory concentration (MIC). Our investigation of antibacterial and antifungal activity of 1-[4-(1,1,3,3-tetra methylbutyl)phenoxy]-3-dialkylamino-2-propanol quaternary salts showed that compounds possess narrow spectrum, as well as broad spectrum action. Significant antimicrobial activity of the novel aryl aliphatic aminoalcohols indicates their potential usage as a component of new antimicrobial drugs.

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42

Donath, Steffen, Holger Militz y Carsten Mai. "Treatment of wood with aminofunctional silanes for protection against wood destroying fungi". Holzforschung 60, n.º 2 (1 de marzo de 2006): 210–16. http://dx.doi.org/10.1515/hf.2006.035.

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AbstractDifferent aminofunctional silanes were tested for their suitability to preserve wood against basidiomycetes in a mini-block experiment according to EN 113. High effectiveness against the brown rot fungusConiophora puteanawas maintained over prolonged exposure times of up to 18 weeks. Resistance against the white rot fungusTrametes versicolorwas only enhanced in the initial phase of exposure (6 weeks); after longer exposure times of 18 weeks, considerable mass losses were observed. It was shown that the antifungal resistance was caused by the amino groups of the oligomeric silane systems, while alkyl groups, which influence the water uptake of wood, only had a minor impact. For effective protection, acidic conditions of the treatment solution were important; this promotes the formation of cationised amino groups (ammonium). The silane quaternary ammonium compound (Si-QAC) 3-(trimethoxysilyl)propyldimethyloctadecyl ammonium chloride was applied in combination with an oligomeric silane system to incorporate quaternary ammonium sites into a SiO2matrix via a sol-gel process. This combined treatment significantly enhanced the decay resistance of pine wood againstC. puteana.

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43

Ryrfeldt, Åke y Eskil Hansson. "Biliary Excretion of Quaternary Ammonium Compounds and Tertiary Amines in the Rat". Acta Pharmacologica et Toxicologica 30, n.º 1-2 (13 de marzo de 2009): 59–68. http://dx.doi.org/10.1111/j.1600-0773.1971.tb00634.x.

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Steidl, Jill V. y Andrea J. Yool. "Distinct Mechanisms of Block of Kv1.5 Channels by Tertiary and Quaternary Amine Clofilium Compounds". Biophysical Journal 81, n.º 5 (noviembre de 2001): 2606–13. http://dx.doi.org/10.1016/s0006-3495(01)75904-8.

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45

Schwärzler, Alexander, Gerhard Laus, Volker Kahlenberg, Klaus Wurst, Thomas Gelbrich, Christoph Kreutz, Holger Kopacka, Günther Bonn y Herwig Schottenberger. "Quaternary 4-Amino-1,2,4-triazolium Salts: Crystal Structures of Ionic Liquids and N-Heterocyclic Carbene (NHC) Complexes". Zeitschrift für Naturforschung B 64, n.º 6 (1 de junio de 2009): 603–16. http://dx.doi.org/10.1515/znb-2009-0604.

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Quaternary salts were prepared by reaction of 4-amino-1,2,4-triazole and 4-amino-3,5-dialkyl- 1,2,4-triazoles (alkyl = Me, Et) with dimethyl and diethyl sulfate at ambient temperature. Subsequent ion metathesis gave hexafluorophosphates and bis(trifluoromethylsulfonyl)imides as crystalline derivatives or ionic liquids.Methylation at 100 ◦C gave the 4-(dimethylamino)-1-methyl-1,2,4- triazolium salt, a precursor for a new carbene ligand which was incorporated into Ag and Rh complexes. The synthesis of 5-bromo-4-(dimethylamino)-1-methyl-1,2,4-triazolium hexafluorophosphate is also reported. Crystal structures of fourteen compounds have been determined by X-ray diffraction

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46

Chen, Jiayin, Jürgen Brockmöller, Tina Seitz, Jörg König, Mladen V. Tzvetkov y Xijing Chen. "Tropane alkaloids as substrates and inhibitors of human organic cation transporters of the SLC22 (OCT) and the SLC47 (MATE) families". Biological Chemistry 398, n.º 2 (1 de febrero de 2017): 237–49. http://dx.doi.org/10.1515/hsz-2016-0236.

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Abstract Tropane alkaloids and their derivatives are anticholinergic drugs with narrow therapeutic range. Here we characterize the organic cation transporters from the SLC22 (OCT1, OCT2, and OCT3) and the SLC47 families (MATE1 and MATE2-K) as potential mediators of the renal and extra-renal excretion, the two major roads of elimination of these substances. All analyzed compounds inhibited and the quaternary amine derivatives ipratropium and trospium were strongly transported by OCTs and MATEs. Overexpression of OCTs or MATEs in HEK293 cells resulted in an up to 63-fold increase in the uptake of ipratropium (Km of 0.32 μm to OCT2 and Vmax of 3.34 nmol×mg protein−1×min−1 to MATE1). The transcellular transport of ipratropium was 16-fold higher in OCT2-MATE1 and 10-fold higher in OCT1-MATE1 overexpressing compared to control MDCKII cells. Genetic polymorphisms in OCT1 and OCT2 affected ipratropium uptake and clinically relevant concentration of ondansetron and pyrithiamine inhibited ipratropium uptake via MATEs by more than 90%. This study suggests that OCT1, OCT2 and MATEs may be strongly involved in the renal and extra-renal elimination of ipratropium and other quaternary amine alkaloids. These substances have a notoriously narrow therapeutic range and the drug-drug interactions suggested here should be further critically evaluated in humans.

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47

Yu, Xin Yang, Liu Yin Xia, Shuai Wang y Hong Zhong. "The Synthesis of Novel Organosilicon Collector QAS222 and its Flotation Performance on Aluminosilicate Minerals". Advanced Materials Research 233-235 (mayo de 2011): 2113–18. http://dx.doi.org/10.4028/www.scientific.net/amr.233-235.2113.

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In the article the organosilicon Quaternary Ammonium surfactant QAS222 was synthesized by one step reaction from silicane coupling agent and dodecyl amine, and its collecting ability to aluminosilicate minerals was investigated. The results showed that the percent conversion of dodecyl amine was more than 95% and the content of novel organosilicon in the production was about 96.53% when reaction was conducted at 80°C for 37 hours, with silicane coupling agent: N, N-Dimethyl dodecyl amine: KI=1.1:1:0.01 by the molar ratio, using anhydrous ethanol as solvent, protecting the reacting system with N2. The synthesizing technology was brief, efficient with low cost and easy to operate and industrialize. The flotation tests indicated that the organosilicon surfactant QAS222 was an effective collector for aluminosilicate minerals in whole pulp pH, by which the kaolinite, pyrophyllite and illite minerals could be floated well. It provided a good way for application preparation of organo-silicon compounds.

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48

Valenta, Vladimír, Jiří Holubek, Emil Svátek y Miroslav Protiva. "Synthesis of 4-methoxyphenoxyacetic and 3,4,5-trimethoxyphenoxyacetic acid amides and hydrazides as potential neurotropic and cardiovascular agents". Collection of Czechoslovak Chemical Communications 52, n.º 12 (1987): 3013–23. http://dx.doi.org/10.1135/cccc19873013.

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4-Methoxyphenoxyacetyl chloride, 3,4,5-trimethoxyphenoxyacetic acid and its methyl ester were reacted with 2-phenylethylamine, 1-benzylpiperazine, 1-(2-phenylethyl)piperazine, 1-(1-phenyl-2-propyl)piperazine, isopropylhydrazine, 1-aminopiperidine, and 4-aminomorpholine and afforded the amides and hydrazides Iab-IVab and Vb-VIIIb. 1-Amino-4-methylpiperazine and 1-amino-4-phenylpiperazine were transformed to the hydrazones XV and XVI, and to the quaternary salts XVII and XVIII. Pharmacological screening showed indications of thymoleptic activity with compounds Ia-IIIa, anorectic effect with IIa and IIIb, antiarrhythmic activity with IIIa, XVII, and XVIII, and myorelaxant effect with XVII and XVIII. Antimicrobial and anthelmintic effects were also noted.

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49

Mondrzyk, Adam, Julian Fischer y Helmut Ritter. "Antibacterial materials: structure-bioactivity relationship of epoxy-amine resins containing quaternary ammonium compounds covalently attached". Polymer International 63, n.º 7 (25 de febrero de 2014): 1192–96. http://dx.doi.org/10.1002/pi.4690.

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50

Cativiela, Carlos y Maria Dolores Diaz-de-Villegas. "ChemInform Abstract: Stereoselective Synthesis of Quaternary α-Amino Acids. Part 2. Cyclic Compounds". ChemInform 31, n.º 23 (8 de junio de 2010): no. http://dx.doi.org/10.1002/chin.200023253.

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