- A Field Dependent (2)H Nuclear Magnetic Relaxation Study of the Aggregation Behavior in Micellar Solutions of CTAB and SDS
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Micellar solutions of cetyltrimethylammonium bromide (CTAB) in water and of sodium dodecyl sulfate (SDS) in 0.22 m NaCl were investigated with field dependent (2)H nuclear magnetic relaxation.The full theoretical model for the molecular dynamics of aggregated surfactant molecules recently developed by Halle (J.Chem.Phys. 1991, 94, 3150.) was applied, making it possible to evaluate the relaxation data in terms of aggregate sizes and shapes.Average aggregation numbers were determined within a simple model for the polydispersity of the solutions.For both systems it was found that nonspherical aggregates were formed at concentrations well below the second cmc.Above the second cmc, the aggregates were found to be rod-shaped and the average aggregation number increased rapidly with the concentration.
- Toernblom, Maria,Henriksson, Ulf,Ginley, Molly
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- Nuclear Magnetic Relaxation in Micellar Systems. Influence of Micellar Size
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An extensive 2H NMR relaxation study for hexadecyltrimethylammonium chloride micelles, with spin-lattice relaxation rates measured at nine magnetic field strengths and spin-spin relaxation rates at three magnetic fields strenghts, is presented.The measured relaxation rates show a strong dependence upon the magnetic field strength, and the data are anlyzed with the "two-step" model of ralaxation.A comparison is made with previously reported relaxation data for dodecyltrimethylammonium chloride micelles and the two-step model proves to be an excellent description of NMR relaxation in spherical micellar systems.Moreover, the motion causing the frequency dependence in the NMR relaxation can be described with an exponential correlation function with a correlation time that increases with the size of the spherical micelles.
- Soederman, O.,Henriksson, U.,Olsson, U.
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- Intermediate Liquid Crystalline Phases in the Binary System C16TACl-H2O: An NMR and Low-Angle X-ray Diffraction Study
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The liquid crystalline phases formed in the concentration range between the hexagonal and the lamellar phase in the binary system C16TACl-H2O have been studied by 2H, 14N, and 35Cl NMR, low-angle X-ray diffraction and optical microscopy.A cubic phase and three anisotropic so-called intermediate phases have been found.At 45 deg C the hexagonal phase is stable up to 75 wt percent C16TACl.Between 75 percent and 79 percent, a biaxial phase (Int-1) built up by long rods with noncircular cross sections is formed.From the asymmetry parameter of the time-averaged electric field gradient tensor the axial ratio of the cross section was found to increase from ca. 1.15 to ca. 1.4 with increasing concentration.In the range 80-83 percent a second intermediate phase (Int-2) is formed with a smaller quadrupole splitting than in the hexagonal phase and with an asymmetry parameter close to 1.A third intermediate phase (Int-3) was detected in some samples.This uniaxial phase has a very small quadrupole splitting (4.4 kHz for 2H in the α-methylene segment).It is suggested that the Int-2 and Int-3 phases are built up by noncubic periodic minimal surfaces, e.g., tetragonally, rhomboedrally, or orthorhombically distorted P or D surfaces.
- Henriksson, Ulf,Blackmore, Eunice S.,Tiddy, Gordon J. T.,Soederman, Olle
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- A METHOD OF TREATING PERIPHERAL INFLAMMATORY DISEASE
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An active for use in the treatment or inhibition of an inflammatory disease associated with over-activation of Toll-like Receptor 4 (TLR4), Toll-like Receptor 2 (TLR2) and Myeloid differentiating protein 88 (Myd88) adaptor-like protein (Mal) while maintaining a subject's ability to respond normally to a pathogen, in which the active is an oleamide or a derivative thereof.
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Paragraph 0078-0084; 0104-0105
(2016/12/01)
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- Aliphatic carboxylic acid amide preparation method
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The invention relates to a preparation method of aliphatic carboxylic acid amide. The method comprises the following step: carrying out a reaction on aliphatic carboxylic acid and monoalkylamine or dialkylamine with 1-4 carbon atoms in the presence of ceric oxide. By using the method, aliphatic carboxylic acid amide can be prepared with high yield, and a catalyst shows an excellent catalytic efficiency and reusing stability.
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Paragraph 0060; 0061; 0084; 0085
(2017/01/09)
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- One pot direct synthesis of amides or oxazolines from carboxylic acids using Deoxo-Fluor reagent
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A mild and highly efficient one pot-one step condensation and/or condensation-cyclization of various acids to amides and/or oxazolines using Deoxo-Fluor reagents is described. Parallel syntheses of various free fatty acids with 2-amino-2,2-dimethyl-1-propanol resulted with excellent yields.
- Kangani, Cyrous O.,Kelley, David E.
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p. 8917 - 8920
(2007/10/03)
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- Modifications of the ethanolamine head in N-palmitoylethanolamine: Synthesis and evaluation of new agents interfering with the metabolism of anandamide
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The endogenous fatty acid amide anandamide (AEA) has, as a result of its actions on cannabinoid and vanilloid receptors, a number of important pharmacological properties including effects on nociception, memory processes, spasticity, and cell proliferation. Inhibition of the metabolism of AEA, catalyzed by fatty acid amide hydrolase (FAAH), potentiates the actions of AEA in vivo and therefore may be a useful target for drug development. In the present study, we have investigated whether substitution of the headgroup of the endogenous alternative FAAH substrate palmitoylethanolamide (PEA) can result in the identification of novel compounds preventing AEA metabolism. Thirty-seven derivatives of PEA were synthesized, with the C16 long chain of palmitic acid kept intact, and comprising 20 alkylated, 12 aromatic, and 4 halogenated amides. The ability of the PEA derivatives to inhibit FAAH-catalyzed hydrolysis of [3H]AEA was investigated using rat brain homogenates as a source of FAAH. Inhibition curves were analyzed to determine the potency of the inhibitable fraction (PI50 values) and the maximal attained inhibition for the compound, given that solubility in an aqueous environment is a major issue for these compounds. In the alkylamide family, palmitoylethylamide and palmitoylallylamide were inhibitors of AEA metabolism with PI50 values of 5.45 and 5.47, respectively. Halogenated derivatives (Cl and Br) exhibit pI50 values of ~5.5 but rather low percentages of maximal inhibition. The -OH group of the ethyl head chain of N-palmitoylethanolamine was not necessary for interaction with FAAH. Amides containing aromatic moieties were less potent inhibitors of AEA metabolism. Compounds containing amide and ester bonds, 13 and 37, showed pI50 values of 4.99 and 5.08, respectively. None of the compounds showed obvious affinity for CB1 or CB2 receptors expressed on Chinese hamster ovary (CHO) cells. It is concluded that although none of the compounds were dramatically more potent than PEA itself at reducing the metabolism of AEA, the lack of effect of the compounds at CB1 and CB2 receptors makes them useful templates for development of possible therapeutic FAAH inhibitors.
- Vandevoorde, Séverine,Jonsson, Kent-Olov,Fowler, Christopher J.,Lambert, Didier M.
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p. 1440 - 1448
(2007/10/03)
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- Acylation de l'acetamidomalonate de diethyle. Synthese et reactivite du 4-ethoxycarbonyl oxazole
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The acylation of diethyl acetamidomalonate by palmitoyl chloride was performed using KOtBu in THF.Subsequent reaction of acylmalonate with DMSO or NMP led to ethyl 5-alkyloxazole-4-carboxylate (global yield 76percent for the two steps).Some original reactions of this heterocycle are presented, including ring opening of oxazole. - Keywords: amphiphilic compounds / Krapcho reaction / trans-acylation / oxazoles
- Loupy, Andre,Petit, Alain,Zaparucha, Anne,Mahieu, Claude,Semeria, Didier
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p. 642 - 647
(2007/10/02)
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- 2,4-disubstituted derivatives of tetrahydrofuran useful for the treatment of PAF mediated illnesses
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The present invention describes novel 2,4-disubstituted derivatives of tetrahydrofuran, having the formula I STR1 wherein: -X- is either an oxygen atom or a covalent single bond; --CH2 XR1 group is in the position 2 and --CH2 OR2 is in the position 4 of the tetrahydrofuran ring, or --CH2 XR1 is in position 4 and --CH2 OR2 in position 2; -R1 represents an alkyl or an alkylaminocarbonyl group; -R2 represents a group having the formula -Y-(CH2)n -Q.(A-)q where -Y- is a covalent single bond, a carbonyl group, a carbonyloxy group or a carbonylamino group; n is an integer 0 to 10; Q is a nitrogen containing heterocycle; q is one when Q is charged or q zero when Q is neutral; and A- is a pharmaceutically acceptable anion. These compounds are PAF antagonists and, thus, useful for the treatment of diseases in which PAF is involved.
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