Lyotropic mesophases of hydroxypropylcellulose in pure acetic acid, in water, and in mixed solvents

The title compound, C19H18N4O3[systematic name: (RS)-1-benzyl-3-hydroxy-3-(2-imino-3-methyl-5-oxoimidazolidin-4-yl)-2,3-dihydro-1H-indol-2-one], was prepared as a racemate (RRandSS) by the aldol condensation ofN-benzylisatin with creatinine in the presence of sodium acetate in acetic acid. The r.m.s. deviation of the isatin ring system is 0.033 Å. The benzyl group is disordered over two orientations, with refined occupancies of 0.847 (7) and 0.153 (7). The dihedral angles between the isatin ring system and the benzene ring (major disorder component) and the imidazole ring are 82.82 (7) and 51.31 (3)°, respectively, In the crystal, molecules are linked into (001) sheets by N—H...O and O—H...N hydrogen bonds, which incorporateR22(9) ring motifs. The crystal was grown from mixed solvents (ethanol, methanol and possibly also ethyl acetate). These solvents are disordered in the crystal and the resulting electron density was found to be uninterpretable. The solvent contribution to the scattering was removed with the SQUEEZE routine inPLATON[Spek (2009).Acta Cryst.D65, 148–155]. The formula mass and density do not take account of the solvent.

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Identification of glycerophospholipids in rapeseed, olive, almond, and sunflower oils by LCMS and LCMSMS

Canadian Journal of Chemistry ◽

10.1139/v04-094 ◽

2004 ◽

Vol 82 (7) ◽

pp. 1210-1215 ◽

Cited By ~ 39

Author(s):

Sadok Boukhchina ◽

Khaled Sebai ◽

Ammar Cherif ◽

Habib Kallel ◽

Paul M Mayer

Keyword(s):

Mass Spectrometry ◽

Acetic Acid ◽

Tandem Mass Spectrometry ◽

Lipid Class ◽

Mixed Solvents ◽

Complex Mixtures ◽

Tandem Mass ◽

Rapid Separation ◽

Diol Column ◽

Sunflower Oils

HPLC employing a thermostatted Lichrospher 100 diol column was used to separate mixtures of glycerophospholipids of rapeseed, olive, almond, and sunflower oils. Elution was performed with a binary gradient of two mixed solvents A: hexane isopropanol acetic acid triethylamine (82:17:1.0:0.08 v/v/v/v) and B: isopropanol water acetic acid triethylamine (85:14:1.0:0.08 v/v/v/v). The LC effluent was directly introduced into the mass spectrometer through an electrospray capillary. Information about the fatty acid composition of each glycerophos pho lipid class was given by tandem mass spectrometry (MSMS). These techniques permitted a rapid separation and identification of complex mixtures of glycerophospholipids. The relative abundance of each lipid class in each oil was also determined. The resulting glycerophospholipid signature may provide an efficient means of identifying oil origin and possible adulteration.Key words: glycerophospholipids, vegetable oils, tandem mass spectrometry, LCMS.

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Lyotropic Mesophases Based an Chitosane Biopolymer, Acetic Acid and Non-Ionic Surfactants, as Delivery Systems of Bioactive Substances

Liquid Crystals and their Application ◽

10.18083/lcappl.2018.3.6 ◽

2018 ◽

Vol 18 (3) ◽

pp. 6-13

Author(s):

N. M. Selivanova ◽

A. T. Gubaidullin ◽

Yu. G. Galyametdinov

Keyword(s):

Acetic Acid ◽

Delivery Systems ◽

Ionic Surfactants ◽

Bioactive Substances ◽

Lyotropic Mesophases

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Ectodesmata as Revealed By Freeze-Etch Preparations of Plant Epidermal Cell Walls

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100072782 ◽

1973 ◽

Vol 31 ◽

pp. 468-469

Author(s):

N.C. Lyon ◽

W. C. Mueller

Keyword(s):

Electron Microscopy ◽

Acetic Acid ◽

Nitric Acid ◽

Oxalic Acid ◽

Light Microscopy ◽

Epidermal Cell ◽

Cell Walls ◽

Plant Viruses ◽

Plant Leaves ◽

Thin Sections

Schumacher and Halbsguth first demonstrated ectodesmata as pores or channels in the epidermal cell walls in haustoria of Cuscuta odorata L. by light microscopy in tissues fixed in a sublimate fixative (30% ethyl alcohol, 30 ml:glacial acetic acid, 10 ml: 65% nitric acid, 1 ml: 40% formaldehyde, 5 ml: oxalic acid, 2 g: mecuric chloride to saturation 2-3 g). Other workers have published electron micrographs of structures transversing the outer epidermal cell in thin sections of plant leaves that have been interpreted as ectodesmata. Such structures are evident following treatment with Hg++ or Ag+ salts and are only rarely observed by electron microscopy. If ectodesmata exist without such treatment, and are not artefacts, they would afford natural pathways of entry for applied foliar solutions and plant viruses.

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