Search Results

Now showing 1 - 10 of 38
  • Item
    2-hydroxyethylammonium iodide
    (Chester : International Union of Crystallography, 2014) Kohrt, C.; Spannenberg, A.; Werner, T.
    In the crystal structure of the title salt, C2H 8NO+·I-, N-H⋯O, N-H⋯I and O-H⋯I hydrogen bonds lead to the formation of layers staggered along the c axis.
  • Item
    Tris(η5-cyclopentadienyl)hafnium(III)
    (Chester : International Union of Crystallography, 2011) Burlakov, V.V.; Arndt, P.; Spannenberg, A.; Rosenthal, U.
    In the crystal structure of the title compound, [Hf(C5H 5)3], three cyclopentadienyl ligands surround the Hf III atom in a trigonal-planar geometry. The molecule lies on a sixfold inversion axis.
  • Item
    {N,N-Bis[bis(2,2,2-trifluoroethoxy)phosphanyl]methylamine- κ2 P,P′}bis(η5-cyclopentadienyl) titanium(II)
    (Chester : International Union of Crystallography, 2013) Haehnel, M.; Hansen, S.; Spannenberg, A.; Beweries, T.
    The title compound, [Ti(C5H5)2(C 9H11F12NO4P2)], is a four-membered titanacycle obtained from the reaction of Cp2Ti(η 2-Me3SiC2SiMe3) and CH 3N[P(OCH2CF3)2]2 {N,N-bis[bis(trifluoroethoxy)phosphanyl]methylamine, tfepma}. The Ti II atom is coordinated by two cyclopentadienyl (Cp) ligands and the chelating tfepma ligand in a strongly distorted tetrahedral geometry. The molecule is located on a mirror plane.
  • Item
    Dicarbonyl-{3,3′-di-tert-butyl-5,5′-di-methoxy-2, 2′-bis[(4,4,5,5-tetraphenyl-1,3,2-dioxaphospho-lan-2-yl)-oxy-κP] biphen-yl}hydridorhodium(I) diethyl ether monosolvate
    (Chester : International Union of Crystallography, 2012) Selent, D.; Spannenberg, A.; Börner, A.
    In the title compound, [Rh(C 74H 68O 8P2)H(CO) 2]·C 4H 10O, the C 2HP 2 coordination set at the Rh I ion is arranged in a distorted trigonal-planar geometry with one P atom of the diphosphite mol-ecule and the H atom adopting the axial coordination sites.
  • Item
    Ethyl 4-chloro-2′-fluoro-3-hydroxy-5-methylbiphenyl-2-carboxylate
    (Chester : International Union of Crystallography, 2011) Adeel, M.; Langer, P.; Villinger, A.
    In the title compound, C 16H 14ClFO 3, the dihedral angle between the mean planes of the two benzene rings is 71.50 (5)°. Due to an intramolecular O - H⋯O hydrogen bond between the hydroxy group and the carbonyl O atom of the ethyl ester group, the ethyl ester group lies within the ring plane. The crystal structure is consolidated by intermolecular C - H⋯O and C - H⋯F interactions.
  • Item
    (Isopropyl-amino)(meth-yl)diphenyl-phospho-nium iodide
    (Chester : International Union of Crystallography, 2011) Peulecke, N.; Peitz, S.; Müller, B.H.; Spannenberg, A.; Rosenthal, U.
    The title compound, C 16H 21NP +· I -, was obtained by the reaction of PH 2PN( iPr)P(Ph)N( iPr)H with MeI involving cleavage of one of the P - N bonds in diethyl ether. The two phenyl rings form a dihedral angle of 82.98 (5)°. A weak donor-acceptor N - H⋯I inter-action is observed.
  • Item
    Secondary Structure and Glycosylation of Mucus Glycoproteins by Raman Spectroscopies
    (Columbus, Ohio : American Chemical Society, 2016) Davies, Heather S.; Singh, Prabha; Deckert-Gaudig, Tanja; Deckert, Volker; Rousseau, Karine; Ridley, Caroline E.; Dowd, Sarah E.; Doig, Andrew J.; Pudney, Paul D. A.; Thornton, David J.; Blanch, Ewan W.
    The major structural components of protective mucus hydrogels on mucosal surfaces are the secreted polymeric gel-forming mucins. The very high molecular weight and extensive O-glycosylation of gel-forming mucins, which are key to their viscoelastic properties, create problems when studying mucins using conventional biochemical/structural techniques. Thus, key structural information, such as the secondary structure of the various mucin subdomains, and glycosylation patterns along individual molecules, remains to be elucidated. Here, we utilized Raman spectroscopy, Raman optical activity (ROA), circular dichroism (CD), and tip-enhanced Raman spectroscopy (TERS) to study the structure of the secreted polymeric gel-forming mucin MUC5B. ROA indicated that the protein backbone of MUC5B is dominated by unordered conformation, which was found to originate from the heavily glycosylated central mucin domain by isolation of MUC5B O-glycan-rich regions. In sharp contrast, recombinant proteins of the N-terminal region of MUC5B (D1-D2-D′-D3 domains, NT5B), C-terminal region of MUC5B (D4-B-C-CK domains, CT5B) and the Cys-domain (within the central mucin domain of MUC5B) were found to be dominated by the β-sheet. Using these findings, we employed TERS, which combines the chemical specificity of Raman spectroscopy with the spatial resolution of atomic force microscopy to study the secondary structure along 90 nm of an individual MUC5B molecule. Interestingly, the molecule was found to contain a large amount of α-helix/unordered structures and many signatures of glycosylation, pointing to a highly O-glycosylated region on the mucin.
  • Item
    Detection of Protein Glycosylation Using Tip-Enhanced Raman Scattering
    (Columbus, Ohio : American Chemical Society, 2016) Cowcher, David P.; Deckert-Gaudig, Tanja; Brewster, Victoria L.; Ashton, Lorna; Deckert, Volker; Goodacre, Royston
    The correct glycosylation of biopharmaceutical glycoproteins and their formulations is essential for them to have the desired therapeutic effect on the patient. It has recently been shown that Raman spectroscopy can be used to quantify the proportion of glycosylated protein from mixtures of native and glycosylated forms of bovine pancreatic ribonuclease (RNase). Here we show the first steps toward not only the detection of glycosylation status but the characterization of glycans themselves from just a few protein molecules at a time using tip-enhanced Raman scattering (TERS). While this technique generates complex data that are very dependent on the protein orientation, with the careful development of combined data preprocessing, univariate and multivariate analysis techniques, we have shown that we can distinguish between the native and glycosylated forms of RNase. Many glycoproteins contain populations of subtly different glycoforms; therefore, with stricter orientation control, we believe this has the potential to lead to further glycan characterization using TERS, which would have use in biopharmaceutical synthesis and formulation research.
  • Item
    Bis(μ2-isopropylimido-κ2 N:N)bis[(η5-cyclopentadienyl)(ethenolato-κO)titanium(IV)]
    (Chester : International Union of Crystallography, 2014) Haehnel, M.; Spannenberg, A.; Rosenthal, U.
    The title dinuclear half-sandwich complex, [CpTi(OCH=CH2) (μ2-N-iPr)]2 (Cp = cyclopentadienyl; iPr = isopropyl), was obtained from the reaction of Cp2TiCl2, n-butyllithium and isopropylamine in tetrahydrofuran. Each TiIV atom is coordinated by one Cp ligand, one vinyloxy unit and two bridging imido groups in a strongly distorted tetrahedral geometry. There are two half molecules in the asymmetric unit, such that whole molecules being generated by inversion symmetry.
  • Item
    Carbonyl{3,3′-di-tert-butyl-5,5′-dimethoxy-2,2′-bis[(4,4, 5,5-tetramethyl-1,3,2-dioxaphospholan-2-yl)oxy]biphenyl-κ2 P,P′}hydrido(triphenylphosphane-κP)rhodium(I) diethyl ether trisolvate
    (Chester : International Union of Crystallography, 2013) Selent, D.; Spannenberg, A.; Börner, A.
    In the title compound, [RhH(C74H68O8P2)(C18H15P)(CO)]·3C4H10O, the CHP3 coordination set at the RhI ion is arranged in a distorted trigonal-bipyramidal geometry with the P atoms adopting equatorial coordination sites and the C atom of the carbonyl ligand as well as the H atom adopting the axial sites. The asymmetric unit contains two very similar molecules of the rhodium complex, two half-occupied diethyl ether molecules and further diethyl ether solvent molecules which could not be modelled successfully. Therefore contributions of the latter were removed from the diffraction data using the SQUEEZE procedure in PLATON [Spek (2009). Acta Cryst. D65, 148-155].