TY - JOUR A1 - Paris, O. A1 - Li, C. A1 - Siegel, S. A1 - Weseloh, G. A1 - Emmerling, Franziska A1 - Riesemeier, Heinrich A1 - Erko, A. A1 - Fratzl, P. T1 - A new experimental station for simultaneous X-ray microbeam scanning for small- and wide-angle scattering and fluorescence at BESSY II JF - Journal of applied crystallography N2 - A new instrument for simultaneous microbeam small- and wide-angle X-ray scattering and X-ray fluorescence (SAXS/WAXS/XRF) is presented. The instrument is installed at the microfocus beamline at BESSY II and provides a beam of 10 µm size with a flux of about 109 photons s-1. A SAXS resolution up to 500 Å d-spacing and a range of scattering vectors of almost three orders of magnitude are reached by using a large-area high-resolution CCD-based detector for simultaneous SAXS/WAXS. The instrument is particularly suited for scanning SAXS/WAXS/XRF experiments on hierarchically structured biological tissues. The necessary infrastructure, such as a cryo-stream facility and an on-site preparation laboratory for biological specimens, are available. KW - Scanning SAXS KW - Scanning WAXS KW - Microbeam KW - Synchrotron radiation PY - 2007 SN - 0021-8898 SN - 1600-5767 VL - 40 IS - Supplement SP - s466 EP - s470 PB - Blackwell CY - Oxford AN - OPUS4-15049 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Köppen, Robert A1 - Emmerling, Franziska A1 - Kohl, Anka A1 - Becker, Roland T1 - Delta-Hexabromocyclododecane JF - Acta crystallographica E N2 - (1R,2S,5R,6S,9S,10R)-Hexabromocyclododecane (C12H18Br6, d-HBCD) was crystallized from acetonitrile. The C—Br distances range from 1.962 (8) to 1.982 (8) Å and intermolecular Br...Br contacts contribute to the formation of layers. PY - 2007 DO - https://doi.org/10.1107/S1600536807026396 SN - 1600-5368 VL - 63 IS - 7 SP - o3105 PB - Munksgaard CY - Copenhagen AN - OPUS4-15048 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Köppen, Robert A1 - Becker, Roland A1 - Emmerling, Franziska A1 - Jung, Christian A1 - Nehls, Irene T1 - Enantioselective Preparative HPLC Separation of the HBCD-Stereoisomers from the Technical Product and Their Absolute Structure Elucidation Using X-Ray Crystallography JF - Chirality N2 - 1,2,5,6,9,10-Hexabromocyclododecane (HBCD) is a widely used flame retardant, which tends to persist in the environment and accumulates in biota. The six stereoisomers (three racemates named α-, β-, and γ-HBCD) of the technical mixture were isolated with high-performance liquid chromatography (HPLC). Direct separations were performed on a chiral stationary phase containing permethylated -cyclodextrin (NUCLEODEX -PM column) and the pure enantiomers of α-, β-, and γ-HBCD were physically characterized for the first time. The absolute configurations of all six isomers were determined by anomalous dispersion using single crystal X-ray crystallography. Optical rotations αD in tetrahydrofuran were +4.2/-4.0 (α-HBCD), +26.1/-27.5 (β-HBCD), and +68.0/-66.3 (γ-HBCD). The sense of rotation could be correlated with the absolute configurations of α-, β-, and γ-HBCD enantiomers and their order of elution on a chiral permethylated β-cyclodextrin-bonded stationary phase. The diastereomers α-, β-, and γ-HBCD displayed distinctly different melting points as well as 1H-, 13C NMR, and IR spectra. KW - Brominated flame retardant KW - Chiral separation KW - Anomalous dispersion KW - Crystal structures KW - Optical rotation KW - Absolute configuration PY - 2007 DO - https://doi.org/10.1002/chir.20366 SN - 0899-0042 SN - 1520-636X VL - 19 IS - 3 SP - 214 EP - 222 PB - Wiley-Liss CY - New York, NY AN - OPUS4-14718 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Emmerling, Franziska A1 - Orgzall, I. A1 - Dietzel, B. A1 - Schulz, Burkhard A1 - Reck, Günter A1 - Schulz, B. T1 - Structural studies on trifluoromethyl substituted 2,5-diphenyl-1,3,4-oxadiazoles JF - Journal of molecular structure N2 - Three new compounds have been synthesized based on the molecular motif 2-[2,6-bis(trifluoromethyl)phenyl]-5-phenyl-1,3,4-oxadiazole, with subsequent CF3-substitution in the ortho-positions of the phenylene ring. The crystal structures of the compounds have been determined by single crystal X-ray diffraction. All compounds have a monoclinic structure. The solid state structure of the compounds is influenced by the electronic properties of the fluorine atoms, leading to the occurrence of C–H...F, and C–F...ϖ interactions, partly replacing ϖ–ϖ interactions usually observed in the crystal structures of 2,5-diphenyl-1,3,4-oxadiazole derivatives. Other significant interactions than those involving fluorine appear only in rare cases. The strong impact of the fluorine atoms on the intra- and intermolecular interactions, and the molecular conformation lead to novel inputs for the understanding of molecular recognition, supramolecular assembly, and crystal packing of fluorine containing compounds. KW - Crystal structure KW - 1,3,4-oxadiazole KW - Molecular conformation KW - Weak interactions PY - 2007 SN - 0022-2860 SN - 1872-8014 SN - 0377-046X VL - 832 IS - 1-3 SP - 124 EP - 131 PB - Elsevier CY - Amsterdam AN - OPUS4-14644 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Köppen, Robert A1 - Emmerling, Franziska A1 - Becker, Roland T1 - Decabromodiphenylethane JF - Acta crystallographica E N2 - Decabromo­diphenyl­ethane [systematic name: 1,1'-ethane-1,2-diylbis(penta­bromo­benzene)], C14H4Br10 (DBDPE), was crystallized from toluene. The mol­ecule shows crystallographic inversion symmetry. The C—Br distances are in the range 1.873 (7)–1.891 (6) Å; inter­molecular BrBr contacts contribute to the formation of ribbons. KW - Single-crystal X-ray study KW - T = 273 K KW - R factor = 0.043 KW - wR factor = 0.121 KW - Data-to-parameter ratio = 20.4 PY - 2007 DO - https://doi.org/10.1107/S1600536807000219 SN - 1600-5368 VL - 63 IS - 2 SP - o585 EP - o586 PB - Munksgaard CY - Copenhagen AN - OPUS4-14565 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tuchalski, G. A1 - Emmerling, Franziska A1 - Gröger, K. A1 - Hänsicke, A. A1 - Nagel, T. A1 - Reck, Günter T1 - X-ray investigations of nebivolol and its isomers JF - Journal of molecular structure N2 - The molecular and crystal structures of the hydrochlorides of d-nebivolol, dl-nebivolol, and seven nebivolol isomers have been determined by X-ray structure analysis. The absolute configuration of all the compounds could be determined unambiguously using anomal dispersion effects. Two compounds, dl-nebivolol (NEB-1d,l) and the (S,R,S,R) nebivolol isomer (NEB-6), crystallize as racemic mixtures in the centrosymmetric space group P-1. d-Nebivolol and six nebivolol isomers crystallize in space group P212121. The d- and l-nebivolol molecules in NEB-1d and NEB-1d,l adopt a conformation which is significantly different compared with that of all nebivolol isomers. With the exception of dl-nebivolol (NEB-1d,l) numerous intermolecular hydrogen bonds connect the molecules forming molecular layers. KW - X-ray crystal structure KW - Nebivolol PY - 2006 DO - https://doi.org/10.1016/j.molstruc.2006.03.086 SN - 0022-2860 SN - 1872-8014 SN - 0377-046X VL - 800 IS - 1-3 SP - 28 EP - 44 PB - Elsevier CY - Amsterdam AN - OPUS4-13800 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Emmerling, Franziska A1 - Orgzall, I. A1 - Reck, Günter A1 - Schulz, Burkhard A1 - Stockhause, S. A1 - Schulz, B. T1 - Structures of substituted di-aryl-1,3,4-oxadiazole derivatives: 2,5-bis(pyridyl)- and 2,5-bis(aminophenyl)-substitution JF - Journal of molecular structure N2 - Crystal structures of four different di-aryl-1,3,4-oxadiazole compounds (aryl = 2-pyridyl-, 3-pyridyl-, 2-aminophenyl-, 3-aminophenyl-) are determined. Crystallization of di(2-pyridyl)-1,3,4-oxadiazole yielded monoclinic and triclinic polymorphs. The structures are characterized by the occurrence of π–π interactions. Additionally, in case of the aminophenyl compounds intra- as well as intermolecular hydrogen bonds are found that influence the packing motif as well. Since these molecules are often used as ligands in metal–organic complexes similarities and differences of the molecular conformation between the molecules in the pure crystals and that of the ligands in the complexes are discussed. KW - Crystal structure KW - 1,3,4-Oxadiazole KW - Molecular conformation KW - Hydrogen bonds PY - 2006 DO - https://doi.org/10.1016/j.molstruc.2006.03.076 SN - 0022-2860 SN - 1872-8014 SN - 0377-046X VL - 800 IS - 1-3 SP - 74 EP - 84 PB - Elsevier CY - Amsterdam AN - OPUS4-13799 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Leiterer, Jork A1 - Leitenberger, W. A1 - Emmerling, Franziska A1 - Thünemann, Andreas A1 - Panne, Ulrich T1 - The use of an acoustic levitator to follow crystallization in small droplets by energy-dispersive X-ray diffraction JF - Journal of applied crystallography N2 - For the investigation of small sample volumes, the use of an acoustic levitator was tested as a `sample holder' for hovering droplets in a synchrotron beam. It might be advantageous to use levitated droplets instead of samples confined in solid holders, especially for the study of crystallization processes where the influence of containing walls has to be minimized. In a first experiment, the crystallization of sodium chloride in a small droplet of aqueous solution has been followed with a time resolution of 30 s. The collected diffraction peaks are compared with data in the ICSD database. KW - EDXD KW - Noncontact measurement technique KW - X-ray-scattering KW - Synchrotron-radiation KW - Acoustic levitation PY - 2006 DO - https://doi.org/10.1107/S0021889806024915 SN - 0021-8898 SN - 1600-5767 VL - 39 IS - 5 SP - 771 EP - 773 PB - Blackwell CY - Oxford AN - OPUS4-13516 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Meißner, T. A1 - Bergmann, R. A1 - Oswald, J. A1 - Rode, K. A1 - Stephan, H. A1 - Richter, W. A1 - Zänker, H. A1 - Kraus, Werner A1 - Emmerling, Franziska A1 - Reck, Günter T1 - Chitosan-encapsulated Keggin anion [Ti2W10PO40]7-.Synthesis, characterization and cellular uptake studies JF - Transition metal chemistry N2 - The Keggin type polyoxotungstate [Ti2W10PO40]7- forms stable associates with the biopolymer chitosan in the nanometer size range. The cluster compound crystallizes from aqueous solution as K4H3[Ti2W10PO40] · 15H2O having a tetragonal structure. Both, the cluster compound and the chitosan/[Ti2W10PO40] associates show a high hydrolytic stability at pH 7.4. The associates formed between the cluster anion [Ti2W10PO40]7- with the polyaminosaccharide chitosan have been characterized by photon correlation spectroscopy, scanning electron microscopy, filtration, centrifugation and zeta potential measurements. The size of the associates formed is in the range of ca. 5×101 to 5×102 nm. These particles have a defined stoichiometry with 5–6 cluster anions bound per molecule chitosan. The isoelectric point determined by zeta potential measurements was found for a cluster anion to chitosan molar ratio of 5.5, indicating the charge neutralization between protonated chitosan and [Ti2W10PO40]7- anions. Cellular uptake studies with [Ti2W10PO40]7- using tumor cell lines FaDu (human squamous carcinoma) and HT-29 (human adenocarcinoma) showed that the tungsten amount inside the cells is remarkably enhanced in the presence of chitosan. KW - Cluster compound KW - Keggin structure KW - Bipolymer KW - Chitosan PY - 2006 DO - https://doi.org/10.1007/s11243-006-0035-z SN - 0340-4285 SN - 1572-901X VL - 31 IS - 5 SP - 603 EP - 610 PB - Springer CY - Dordrecht AN - OPUS4-12568 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kraus, Werner A1 - Walther, M. A1 - Jung, C. M. A1 - Emmerling, Franziska A1 - Pietzsch, H.-J. T1 - Bromotricarbonyl{15-[2-(methylsulfanyl)ethylsulfanyl]pentadecanoic acid-kappa2S,S'}rhenium(I) JF - Acta crystallographica E N2 - The title compound, [ReBr(C18H36O2S2)(CO)3], was synthesized and characterized as a non-radioactive surrogate of a novel Tc-containing fatty acid derivative prepared according to the tricarbonyl/dithioether design with the objective of developing new Tc-based radiopharmaceuticals for the non-invasive diagnosis of myocardial metabolism. The Re chelate contains the metal in the oxidation state +1 and is attached to the terminal position of a fatty acid. The complex formation was accomplished by a ligand exchange reaction using [NBu4]2[Re(CO)3Br3] as starting material. KW - Fatty acid KW - Tc-compound KW - Radio-pharmaceutical PY - 2006 DO - https://doi.org/10.1107/S1600536806024081 SN - 1600-5368 VL - 62 IS - 7 SP - m1660 EP - m1662 PB - Munksgaard CY - Copenhagen AN - OPUS4-12529 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -