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  • 11
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    The @journal of organic chemistry 60 (1995), S. 7891-7895 
    ISSN: 1520-6904
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 12
    Electronic Resource
    Electronic Resource
    Oxford [u.a.] : International Union of Crystallography (IUCr)
    Acta crystallographica 57 (2001), S. 1098-1100 
    ISSN: 1600-5759
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: At 160 K, the glucopyranosyl ring of the title compound, C20H28ClIO13, has a near-ideal 4C1 conformation and the fructofuranosyl ring has a twist 4T3 conformation. The two hydroxy groups are involved in intra- and intermolecular hydrogen bonds, with the latter interactions linking the molecules into infinite one-dimensional chains. The absolute configuration of the molecule has been determined.
    Type of Medium: Electronic Resource
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  • 13
    Electronic Resource
    Electronic Resource
    Copenhagen : International Union of Crystallography (IUCr)
    Acta crystallographica 55 (1999), S. 396-409 
    ISSN: 1600-5740
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: The chloromercurate(II) salts of 2-, 3- and 4-chloropyridine display a variety of anion stoichiometries and structures, including the rare [Hg3Cl10]4− stoichiometry. 2-Chloropyridinium trichloromercurate(II), (I), (C5H5ClN)[HgCl3], monoclinic, P21/n, a = 9.094 (8), b = 18.143 (4), c = 12.902 (3) Å, β = 106.13 (4)° with Z = 8, has the [HgCl3]− stoichiometry, but the anions are infinite chains composed of [HgCl3]−, HgCl2 and Cl− moieties linked by longer Hg...Cl contacts. Hydrogen bonds link the cations to the formal Cl− ions. Tetrakis(3-chloropyridinium) decachlorotrimercurate(II), (II), (C5H5ClN)4[Hg3Cl10], monoclinic, P21/n, a = 7.522 (2), b = 28.046 (3), c = 9.165 (2) Å, β = 105.78 (2)° with Z = 2, has the rare [Hg3Cl10]4− stoichiometry and contains infinite one-dimensional double-stranded {([HgCl4]2−)2 [HgCl2]}n anionic chains made up of linear HgCl2 and distorted [HgCl4]2− entities linked together by longer Hg...Cl contacts. The HgCl2 moieties are joined by double [HgCl4]2− bridges. Hydrogen bonds link the cations to the sides of the anionic columns. Tetrakis(4-chloropyridinium) decachlorotrimercurate(II), (III), (C5H5ClN)4[Hg3Cl10], triclinic, P1¯, a = 9.907 (3), b = 13.226 (2), c = 7.282 (2) Å, α = 84.41 (2), β = 74.81 (2), γ = 87.34 (2)° with Z = 1, also has the [Hg3Cl10]4− stoichiometry and the same type of {([HgCl4]2−)2[HgCl2]}n anionic chains that were found in compound (II), but the formal HgCl2 and [HgCl4]2− moieties are more discrete with much weaker contacts linking the individual units. Bifurcated hydrogen bonds with the cations cross-link the anionic chains to form an infinite two-dimensional network. Second forms of the 3- and 4-chloropyridinium salts were also obtained. 3-Chloropyridinium trichloromercurate(II), (IV), (C5H5ClN)[HgCl3], monoclinic, P21/c, a = 7.243 (5), b = 22.145 (8), c = 12.320 (3) Å, β = 99.52 (3)° with Z = 8, has the [HgCl3]− stoichiometry, but the anions are infinite chains composed of distorted [Hg2Cl6]2− moieties. Bifurcated hydrogen bonds from the cations cross-link the anionic chains to form infinite two-dimensional layers. Bis(4-chloropyridinium) hexachlorodimercurate(II), (V), (C5H5ClN)2[Hg2Cl6], monoclinic, C2/m, a = 13.447 (3), b = 7.534 (2), c = 9.939 (2) Å, β = 97.48 (2)° with Z = 2, contains highly symmetrical discrete [Hg2Cl6]2−anions. Bifurcated hydrogen bonds from the cations interconnect the anions to form infinite one-dimensional chains.
    Type of Medium: Electronic Resource
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  • 14
    Electronic Resource
    Electronic Resource
    Oxford [u.a.] : International Union of Crystallography (IUCr)
    Acta crystallographica 57 (2001), S. 1418-1420 
    ISSN: 1600-5759
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: In each of the two pyranoid sugars, ethyl 2-deoxy-4,5,6,8-tetra-O-acetyl-α-D-gluco-3,7-pyranoso-3-octulosonate, C18H26O12, and ethyl 2-deoxy-4,5,6,8-tetra-O-benzyl-α-D-galacto-3,7-pyranoso-3-octulosonate, C38H42O8, the anomeric configuration is α. The acetoxymethyl substituent on the hexopyranose ring of the former compound and the ethoxycarbonylmethyl substituents in both sugars all have the gauche–trans conformation, while the benzyloxymethyl substituent of the galactopyranose sugar has the trans–gauche conformation. In each structure, the anomeric hydroxy group forms an intramolecular hydrogen bond with the carbonyl O atom of the ethoxycarbonylmethyl substituent.
    Type of Medium: Electronic Resource
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  • 15
    Electronic Resource
    Electronic Resource
    Oxford [u.a.] : International Union of Crystallography (IUCr)
    Acta crystallographica 57 (2001), S. 634-637 
    ISSN: 1600-5759
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: The morpholine ring of the title dione, C13H15NO3, shows a boat conformation that is distorted towards a twist-boat, with the boat ends being the two Csp3 atoms of the ring. The benzyl substituent is in the favoured `exo' position. In the monothione derivative, (±)-6-benzyl-3,3-dimethyl-5-thioxomorpholin-2-one, C13H15NO2S, this ring has a much flatter conformation that is midway between a boat and an envelope, with the dimethyl end being almost planar. The orientation of the benzyl group is `endo'. The dithione derivative, (±)-6-benzyl-3,3-dimethylmorpholine-2,5-dithione, C13H15NOS2, has two symmetry-independent molecules, which show different puckering of the morpholine ring. One molecule has a flattened envelope conformation distorted towards a screw-boat, while the conformation in the other molecule is similar to that in the monothione derivative. Intermolecular hydrogen bonds link the molecules in the three compounds, respectively, into centrosymmetric dimers, infinite chains, and dimers made up of one of each of the symmetry-independent molecules.
    Type of Medium: Electronic Resource
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  • 16
    Electronic Resource
    Electronic Resource
    Oxford [u.a.] : International Union of Crystallography (IUCr)
    Acta crystallographica 56 (2000), S. 616-618 
    ISSN: 1600-5759
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: The title compound, [2aS-(2aα,4aα,5α,7bα)]-5-(β-D-glucopyranosyloxy)-2a,4a,5,7b-tetrahydro-1-oxo-1H-2,6-dioxacyclopent[cd]inden-4-ylmethyl acetate monohydrate, C18H22O11·H2O, was extracted from the Turkish plant Putoria calabrica (L. fil.) DC. The three fused rings have envelope or distorted envelope conformations and form a bowl in which ring strain causes distortion of some bond angles and significant pyramidalization of two of the Csp2 atoms. The ring junction H atoms are all cis to one another and the glycosidic linkage is in the β axial position. The structure incorporates two symmetry-independent water molecules, each of which is located on a twofold axis. Intermolecular hydrogen bonds involving all the hydroxy groups and water molecules link the molecules into a complex three-dimensional framework.
    Type of Medium: Electronic Resource
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  • 17
    Electronic Resource
    Electronic Resource
    Oxford [u.a.] : International Union of Crystallography (IUCr)
    Acta crystallographica 56 (2000), S. 351-353 
    ISSN: 1600-5759
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: The title compound, C19H18BrNO3, has potential calcium modulatory properties. The 1,4-dihydropyridine ring has a very shallow boat conformation and is one of the most planar examples of this moiety. The 2-bromophenyl substituent is in the axial synperiplanar orientation. The quinoline ring has a half-chair conformation, with the unusual arrangement of the out-of-plane atom being on the opposite side of the ring plane to the bromophenyl substituent. The molecules are linked into chains by intermolecular hydrogen bonds.
    Type of Medium: Electronic Resource
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  • 18
    Electronic Resource
    Electronic Resource
    Oxford [u.a.] : International Union of Crystallography (IUCr)
    Acta crystallographica 57 (2001), S. 1363-1366 
    ISSN: 1600-5759
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: At 160 K, the structure of 4-bromo-4-deoxysucrose, C12H21BrO10, is very similar to that of sucrose, particularly with respect to the conformation of the glycosidic linkage. As in sucrose, an intramolecular hydrogen bond exists between the glucopyranosyl and the fructofuranosyl rings. Conversely, the structure of 1′,6′-dibromo-4-fluoro-4,1′,6′-trideoxysucrose monohydrate, C12H19Br2FO8·H2O, shows large conformational differences when compared with the structures of both sucrose and sucralose. This compound does not exhibit any intramolecular hydrogen bonds. In each compound, a complex series of intermolecular hydrogen bonds link the molecules into an infinite three-dimensional framework. The absolute configuration of each molecule has been determined.
    Type of Medium: Electronic Resource
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  • 19
    Electronic Resource
    Electronic Resource
    Oxford [u.a.] : International Union of Crystallography (IUCr)
    Acta crystallographica 56 (2000), S. 1004-1006 
    ISSN: 1600-5759
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: The title compounds are diastereoisomers with antipodean axial chirality. The M isomer crystallizes as a (1/3) acetone solvate, C32H30NO+·Br−·3C3H6O, while the P isomer crystallizes as a (1/1) dichloromethane solvate, C32H30NO+·Br−·CH2Cl2. In each structure, O—H...Br hydrogen bonds link the cations and anions to give ion pairs. The seven-membered azepinium ring adopts the usual twisted-boat conformation and its ring strain causes a slight curvature of the plane of each naphthyl ring.
    Type of Medium: Electronic Resource
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  • 20
    Electronic Resource
    Electronic Resource
    Oxford [u.a.] : International Union of Crystallography (IUCr)
    Acta crystallographica 57 (2001), S. 764-766 
    ISSN: 1600-5759
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: The tetrathiane ring of the title compound, C26H16S4, has a chair conformation and the molecule has approximate C2 symmetry. Each of the two fluorene ring systems is virtually planar, with the ring planes intersecting at an angle of 67.58 (5)°. This novel compound has been formed as a side product from the treatment of 9H-fluorene-9-thione with methyl N-[(benzylidene)phenyl]glycinate in the presence of LiBr and 1,6-diazabicyclo[5.4.0]undecane.
    Type of Medium: Electronic Resource
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