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Unit Cell Dimensions (unit + cell_dimension)
Selected AbstractsCrystal structure analysis of {[,-N,N,-Bis(salicylidene)-1,3-propanediaminato]nickel(II)}dichloromercury(II)CRYSTAL RESEARCH AND TECHNOLOGY, Issue 2 2006C. Ar Abstract The title compound, a hetero-dinuclear complex with Ni(II) and Hg(II) ions, forms crystals which belong to the triclinic system, space group P1, with unit cell dimensions a = 8.9620(12), b = 9.2370(11), c = 12.0810(13) Å, , = 92.100(3)° , , = 105.317(5)°, , = 110.502(3)°, V = 894.2(2) Å3. The cell contains two molecules. The Ni,Hg distance is 3.4859(7) Å. The distance Hg...Hga (symmetry code: -x,-y,-z) between the neighbouring molecules is 4.7514(7) Å. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Synthesis, spectroscopic studies and ab-initio structure determination from X-ray powder diffraction of bis-(N-3-acetophenylsalicylaldiminato)copper(II)CRYSTAL RESEARCH AND TECHNOLOGY, Issue 8 2005S. Banerjee Abstract The synthesis, spectroscopic studies and crystal structure determination from X-ray powder diffraction have been carried out for bis-(N-3-acetophenylsalicylaldiminato)copper(II). The structure is triclinic, space group P1 with unit cell dimensions a = 11.817(1) Å, b = 12.087(1) Å, c = 9.210(1) Å, , = 102.62(1)°, , = 111.16(1)°, , = 86.15(1)°, V = 1197.0(2)Å3, Z = 2. The structure has been solved by Monte Carlo simulated annealing approach and refined by GSAS package. The final Rp value was 8.68%. The coordination geometry around the copper atom in the complex is intermediate between square-planar and tetrahedral with two salicylaldimine ligands in trans arrangement. Intermolecular C,H,O hydrogen bonds between molecules related by translation generate infinite chains along [010] direction. The molecular chains are linked via additional C,H,O hydrogen bonds to form a three-dimensional supramolecular network. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Engineering of a monomeric and low-glycosylated form of human butyrylcholinesteraseFEBS JOURNAL, Issue 2 2002Expression, characterization, crystallization, purification Human butyrylcholinesterase (BChE; EC 3.1.1.8) is of particular interest because it hydrolyzes or scavenges a wide range of toxic compounds including cocaine, organophosphorus pesticides and nerve agents. The relative contribution of each N-linked glycan for the solubility, the stability and the secretion of the enzyme was investigated. A recombinant monomeric BChE lacking four out of nine N-glycosylation sites and the C-terminal oligomerization domain was stably expressed as a monomer in CHO cells. The purified recombinant BChE showed catalytic properties similar to those of the native enzyme. Tetragonal crystals suitable for X-ray crystallography studies were obtained; they were improved by recrystallization and found to diffract to 2.0 Å resolution using synchrotron radiation. The crystals belong to the tetragonal space group I422 with unit cell dimensions a = b = 154.7 Å, c = 124.9 Å, giving a Vm of 2.73 Å3 per Da (estimated 60% solvent) for a single molecule of recombinant BChE in the asymmetric unit. The crystal structure of butyrylcholinesterase will help elucidate unsolved issues concerning cholinesterase mechanisms in general. [source] Complexes of Co(II) and Zn(II) with ofloxacin.JOURNAL OF PHARMACEUTICAL SCIENCES, Issue 11 2002Crystal structure of [Co(oflo)2(MeOH)2]·4MeOH Abstract Ofloxacin (oflo) is able to interact with Co(II) and Zn(II) salts to form complexes with the general formula [M(oflo)2],·,4H2O, (M,=,Co, Zn). Bonding takes place through one of the oxygen atoms of the carboxylate group (acting as a monodentate) and the oxygen atom of the ketonic group. The IR bands of the carboxylic and ketonic group at 1713 and 1622 cm,1, respectively, shift to 1615 and 1575 cm,1 in the complexes. After dissolution in methanol, complex [Co(oflo)2],·,4H2O crystallizes as [Co(oflo)2(MeOH)2],·,4MeOH, where Co(II) ion is in an octahedral environment of oxygen atoms. This compound crystallizes in the triclinic system, spatial group P-1, with unit cell dimensions a,=,9.3670(12), b,=,11.4135(17), c,=,11.851(2) Å y ,,=,71.999(14), ,,=,73.698(12), ,,=,83.528(14)°. Magnetic properties (effective magnetic moment 5.02 BM) and visible spectrum (bands at 490, 510, and 1152 nm) are characteristic of such an octahedral geometry. 1H- and 13C-NMR spectra of the Zn(II) complex indicate only small structural changes in ofloxacin upon coordination to the metallic site. © 2002 Wiley-Liss, Inc. and the American Pharmaceutical Association J Pharm Sci 91:2416,2423, 2002 [source] Synthesis and Structural Characterization of 1,4-Di(2-methoxyphenyl)-2,5-piperazinedioneCHINESE JOURNAL OF CHEMISTRY, Issue 5 2007Shu-Sheng Zhang Abstract A new derivative of 2,5-piperazinedione, 1,4-di(2-methoxyphenyl)-2,5-piperazinedione (I), was synthesized by the cyclocondensation reaction of N -2-methoxyphenyl chloroacetamide, and its structure was characterized by elemental analysis, IR, 1H NMR and single crystal X-ray diffraction method. The crystal belongs to monoclinic system, space group P21/c with unit cell dimensions a=0.56934(10) nm, b=1.3880(2) nm, c=1.00329(17) nm, ,=90.376(3)°, V=0.7928(2) nm3, Z=2, Dc=1.367 g·cm,3, ,=0.98 cm,1, R and wR being 0.0606 and 0.1564 respectively for 1549 unique reflections with 1247 observed reflections [I>2,(I)]. The molecule has a crystallographically imposed symmetry center. The three rings in the molecule are each coplanar with their attached groups, excluding methyl H atoms and the H atoms attached to the piperazinedione ring, while the whole molecule is not planar, with dihedral angles of 74.7(1)° between the piperazinedione and each of the two aromatic rings. The crystal structure is stabilized by van der Waals and dipole-dipole forces. [source] Synthesis and characterization of diorganotin compounds {[R2Sn(ON=CHC6H5)]2O}2 and crystal structure of {[(CsH5CH2)2Sn(ON=CHC6H5)]2O}2CHINESE JOURNAL OF CHEMISTRY, Issue 10 2004Han-Dong Yin Abstract Diorganotin compounds ([R2Sn(ON=CHC6H5)]2O)2 [R=C6H5CH2 (1), 2-FC6H4CH2 (2), 4-FC6H4CH2 (3), 2-ClC6H4CH2 (4), 4-ClC6H4CH2 (5)] were synthesized by the reaction of R2SnO with HON=CHC6H5 in 1:1 molar ratio in refluxing anhydrous benzene or toluene. They were characterized by elemental analysis, IR, 1H NMR and 119Sn NMR spectroscopy. And two sets of 119Sn chemical shifts were observed in the 119Sn NMR spectra of these compounds, indicating the presence of two types of environment around the tin atoms. The crystal structure of compound 1 was determined by X-ray single crystal diffraction analysis. The results showed that the crystal of compound 1 belongs to a monoclinic system with space group P21/c and unit cell dimensions: ,=1.0718(9) nm, b=1.9666(17) nm, c=2.0480(17) nm, ,=96.4371(14)°, Dc=1.450 g/cm3, Z=2, F(000)=1888, V=4.290(6) nm3, ,=1.206 mm,1, R1=0.0405, wR2=0.0786. The compound 1 belongs to centrosymmetric dimer structure mode with a four-membered central endo-cyclic Sn2O2 unit in which the bridging oxygen atoms are hi-coordinated. Each bridging oxygen atom also connects with an em-cyclic tin atom. The endo - and exo -cyclic tin atoms are both five-coordinated, and have coordination geometry of distorted trigonal bipyramid. [source] | ||||||||||