共查询到20条相似文献,搜索用时 0 毫秒
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Jan J. Weigand Andreas Decken Neil Burford 《Acta Crystallographica. Section C, Structural Chemistry》2008,64(2):o64-o66
In the molecular crystal of hexaphenylhexaphosphinane benzene solvate, C36H30P6·C6H6, representing the trigonal form of phosphobenzene as a solvate, the six‐membered ring of P atoms adopts a chair conformation wherein the six phenyl groups are located in equatorial positions. The molecules [molecular symmetry (C3i)] are stacked infinitely along the c‐axial direction. 相似文献
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Qiguang Wang Liang Xie Jianjun Zhai 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(2):197-198
The crystal structure of tylophorine B (or 2,3,6‐trimethoxyphenanthro[9,10‐f]indolizidine) as the benzene solvate, C23H25NO3·C6H6, has been determined. The compound was isolated from albizzia julibrissin and this is the first definitive report of the steochemistry of tylophorine. 相似文献
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Jamal Pratt Janna Hutchinson Cheryl L. Klein Stevens 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(12):o487-o491
The X‐ray crystal structures of solvates of sulfapyridine have been determined to be conformational polymorphs. 4‐Amino‐N‐(1,2‐dihydropyridin‐2‐ylidene)benzenesulfonamide (polymorph III), C11H11N3O2S, (1), 4‐amino‐N‐(1,2‐dihydropyridin‐2‐ylidene)benzenesulfonamide 1,3‐dioxane monosolvate, C11H11N3O2S·C4H8O2, (2), and 4‐amino‐N‐(1,2‐dihydropyridin‐2‐ylidene)benzenesulfonamide tetrahydrofuran monosolvate, C11H11N3O2S·C4H8O, (3), crystallized as the imide form, while piperidin‐1‐ium 4‐amino‐N‐(pyridin‐2‐yl)benzenesulfonamidate, C5H12N+·C11H10N3O2S−, (4), crystallized as the piperidinium salt. The tetrahydrofuran and dioxane solvent molecules in their respective structures were disordered and were refined using a disorder model. Three‐dimensional hydrogen‐bonding networks exist in all structures between at least one sulfone O atom and the aniline N atom. 相似文献
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The solubility of stearic acid in supercritical CO2 with acetonitrile (CH3CN) cosolvent was measured at 318.15 K in the pressure range from 9.5 to 16.5 MPa, and the cosolvent concentration ranges from 0. 0 to 5.5 mol% . The solubility increases with acetonitrile concentration and pressure, and it also increases with the apparent density of CO2 d1(moles of CO2 in per liter of fluid) at higher cosolvent concentrations. At lower d1, however, the solubility of the acid at lower acetonitrile concentrations is lower than that in pure CO2 provided that d1 is fixed, which is discussed qualitatively based on the clustering of the components in the system. 相似文献
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Beatrice Nicolaï P. Espeau R. Céolin M. -A. Perrin L. Zaske J. Giovannini F. Leveiller 《Journal of Thermal Analysis and Calorimetry》2007,90(2):337-339
Spironolactone (C24H32O4S) usually crystallizes into an orthorhombic phase, named Form II. Another orthorhombic phase, named Form I, is also known
but seems difficult to obtain. Studies of the kinetics of desolvation of the ethanol solvate at room temperature showed that
these two forms can be obtained through different mechanisms of desolvation. 相似文献
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A new fused heterocyclic derivatives of pyrrole containing acetonitrile or cyanoacetonitrile moiety at 3-position is described by a one-pot multicomponent reaction. The reaction of dimedone, various aniline, aryl glyoxal with malononitrile/ethyl cyanoacetate/methyl cyanoacetate under mild conditions. The present method does not involve any hazardous organic solvents or catalysts. The significant features of this method are readily available starting materials, good yields, and easy purification. 相似文献
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Genivaldo Julio Perptuo Jan Janczak 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(2):o112-o114
The crystals of the title new melaminium salt, 2,4,6‐triamino‐1,3,5‐triazin‐1‐ium acetate acetic acid solvate monohydrate, C3H7N6+·CH3COO?·CH3COOH·H2O, are built up from singly protonated melaminium residues, acetate anions, and acetic acid and water molecules. The melaminium residues are interconnected by N—H?N hydrogen bonds to form chains along the [010] direction. These chains of melaminium residues form stacks aligned along the a axis. The acetic acid molecules interact with the acetate anions via the H atom of their carboxylic acid groups and, together with the water molecules, form layers that are parallel to the (001) plane. The oppositely charged moieties interact via multiple N—H?O hydrogen bonds that stabilize a pseudo‐two‐dimensional stacking structure. 相似文献
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Alina A. Beloborodova Vasily S. Minkov Elena V. Boldyreva 《Acta Crystallographica. Section C, Structural Chemistry》2016,72(12):997-1001
The loop diuretic furosemide is used widely in the treatment of congestive heart failure and edema, and is practically insoluble in water. The physicochemical and pharmacokinetic properties of drugs can be modified by preparing the drug in an appropriate solid‐state form. A new solvate of furosemide with dimethylacetamide (DMA) {systematic name: 4‐chloro‐2‐[(furan‐2‐yl)methylamino]‐5‐sulfamoylbenzoic acid N,N‐dimethylacetamide disolvate}, C12H11ClN2O5S·2C4H9NO, (I), is reported. The channeled structure formed on slow crystallization contains DMA solvent molecules in its channels. This structure adds to the evidence of varied conformations observed across all known structures, so supporting the idea that this flexible molecule has conformational lability. The current structure also differs from those of other previously known furosemide solvates in the number of solvent molecules per furosemide molecule, viz. 2:1 instead of 1:1. Desolvation of (I) gives the most stable form of furosemide, i.e. Form I. 相似文献
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