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Acta Crystallographica. Section C, Structural Chemistry

Qiu Ying Huang, Yang Zhao, Xiang Ru Meng
Careful choice of the organic ligands is one of the most important parameters in the rational design and synthesis of coordination polymers. Aromatic polycarboxylates have been widely used in the preparation of metal-organic polymers since they can utilize various coordination modes to form diverse structures and can act as hydrogen-bond acceptors and donors in the assembly of supramolecular structures. Nitrogen-heterocyclic organic compounds have also been used extensively as ligands for the construction of polymers with interesting structures...
August 1, 2017: Acta Crystallographica. Section C, Structural Chemistry
Ilia A Guzei, Lara C Spencer, Sondra C Buechel, Leah B Kaufmann, Curtis J Czerwinski
The steric and electronic factors that influence which of the two rings of a substituted biphenyl ligand coordinates to chromium are of interest and it has been suggested that haptotropic rearrangements within these molecules may be limited if the arene-arene dihedral angle is too large. Two tricarbonylchromium(0) complexes and their respective free ligands have been characterized by single-crystal X-ray diffraction. In the solid state, tricarbonyl[(1',2',3',4',5',6'-η)-2-fluoro-1,1'-biphenyl]chromium(0), [Cr(C12H9F)(CO)3], (I), exists as the more stable isomer with the nonhalogenated arene ring ligated to the metal center...
August 1, 2017: Acta Crystallographica. Section C, Structural Chemistry
Szabolcs Balogh, Gergely Farkas, Tamás Holczbauer, József Bakos
Phosphine-phosphoramidites (PPAs) are heterobidentate ligands that have been developed in the last two decades and have been used successfully in asymmetric catalytic reactions. A single crystal of the PPA (11bS)-N-[(2S,4S)-4-(diphenylphosphanyl)pentan-2-yl]-N-methyldinaphtho[2,1-d:1',2'-f][1,3,2]dioxaphosphepin-4-amine, C38H35NO2P2, was prepared and structurally characterized by single-crystal X-ray diffraction and density functional theory (DFT) calculations. Structure elucidation revealed unique features which might have a significant effect in the excellent chemical stability of this type of molecule...
August 1, 2017: Acta Crystallographica. Section C, Structural Chemistry
Lawrence W Y Wong, Jack W H Kan, Herman H Y Sung, Ian D Williams
Spiroborate anions have potential for crystallization or resolution and chiral bis(mandelato)borate anions can be used for the efficient resolution of a diverse range of racemic cations via diastereomeric salt formation. The syntheses, X-ray crystal structures and solubilities of three chiral bis(mandelato)borate salts, namely poly[[aqua-μ3-bis[(R)-mandelato]borato-lithium(I)] monohydrate], [Li(C16H12BO6)(H2O)]n or Li[B(R-Man)2]·H2O, (1), ammonium bis[(R)-mandelato]borate, NH4(+)·C16H12BO6(-) or NH4[B(R-Man)2], (2), and tetra-n-butylammonium bis[(R)-mandelato]borate, C16H36N(+)·C16H12BO6(-) or NBu4[B(R-Man)2], (3), are reported...
August 1, 2017: Acta Crystallographica. Section C, Structural Chemistry
Katherine M Van Heuvelen, Isabell Lee, Katherine Arriola, Rilke Griffin, Christopher Ye, Michael K Takase
The tetraazamacrocyclic ligand 1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane (TMC) has been used to bind a variety of first-row transition metals but to date the crystal structure of the cobalt(II) complex has been missing from this series. The missing cobalt complex chlorido(1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane-κ(4)N)cobalt(II) chloride dihydrate, [CoCl(C14H32N4)]Cl·2H2O or [Co(II)Cl(TMC)]Cl·2H2O, crystallizes as a purple crystal. This species adopts a distorted square-pyramidal geometry in which the TMC ligand assumes the trans-I configuration and the chloride ion binds in the syn-methyl pocket of the ligand...
August 1, 2017: Acta Crystallographica. Section C, Structural Chemistry
Anton I Smolentsev
Functionalized acid amides are widely used in biology, medicine, environmental chemistry and many other areas. Among them, pyridine-substituted amides, in particular N-(pyridin-2-yl)acetamide and its derivatives, play an important role due to their excellent chelating properties. The donor properties of these ligands can be effectively modified by introducing electron-donating substituents (e.g. alkyl groups) into the heterocycle. On the other hand, substituents in the α-position of the pyridine ring can create steric hindrance, which significantly influences the coordination number and geometry...
August 1, 2017: Acta Crystallographica. Section C, Structural Chemistry
Seyed Amir Zarei, Mohammad Piltan, Asmar Mashhun, Hadi Amiri Rudbari, Giuseppe Bruno
The title Schiff base compound {systematic name: 2-[5-[(E)-(2-hydroxybenzylidene)amino]-4-(2-{5-[(E)-(2-hydroxybenzylidene)amino]-2-(2-hydroxyphenyl)-1,3-thiazol-4-yl}disulfanyl)-1,3-thiazol-2-yl]phenol}, C32H22N4O4S4, incorporating a disulfanediyl (dithio) linkage, was obtained from the condensation reaction between two equivalents of salicylaldehyde and one equivalent of dithiooxamide in dimethylformamide, and was characterized by elemental analysis, IR spectroscopic analysis and single-crystal X-ray diffraction...
August 1, 2017: Acta Crystallographica. Section C, Structural Chemistry
Karolina Schwendtner, Uwe Kolitsch
The crystal structures of hydrothermally synthesized aluminium dihydrogen arsenate(V) dihydrogen diarsenate(V), Al(H2AsO4)(H2As2O7), gallium dihydrogen arsenate(V) dihydrogen diarsenate(V), Ga(H2AsO4)(H2As2O7), and diindium bis[dihydrogen arsenate(V)] bis[dihydrogen diarsenate(V)], In2(H2AsO4)2(H2As2O7)2, were determined from single-crystal X-ray diffraction data collected at room temperature. The first two compounds are representatives of a novel sheet structure type, whereas the third compound crystallizes in a novel framework structure...
August 1, 2017: Acta Crystallographica. Section C, Structural Chemistry
Norman Lu, Hsing Fang Chiang, Rong Jyun Wei, Yuh Sheng Wen, Ling Kang Liu
The salts 3-[(2,2,3,3-tetrafluoropropoxy)methyl]pyridinium saccharinate, C9H10F4NO(+)·C7H4NO3S(-), (1), and 3-[(2,2,3,3,3-pentafluoropropoxy)methyl]pyridinium saccharinate, C9H9F5NO(+)·C7H4NO3S(-), (2), i.e. saccharinate (or 1,1-dioxo-1λ(6),2-benzothiazol-3-olate) salts of pyridinium with -CH2OCH2CF2CF2H and -CH2OCH2CF2CF3 meta substituents, respectively, were investigated crystallographically in order to compare their fluorine-related weak interactions in the solid state. Both salts demonstrate a stable synthon formed by the pyridinium cation and the saccharinate anion, in which a seven-membered ring reveals a double hydrogen-bonding pattern...
August 1, 2017: Acta Crystallographica. Section C, Structural Chemistry
J August Ridenour, Mikaela M Pyrch, Zachery J Manning, Jeffery A Bertke, Christopher L Cahill
The crystal structures of two new bimetallic uranyl-transition metal compounds with diglycolic acid [or 2-(carboxymethoxy)acetic acid] have been hydrothermally synthesized and structurally characterized via single-crystal X-ray diffraction. The compounds, namely catena-poly[[[tetraaquamanganese(II)]-μ-2,2'-oxydiacetato-[dioxidouranium(VI)]-μ-2,2'-oxydiacetato] dihydrate], {[MnU(C4H4O5)2O2(H2O)4]·2H2O}n, and catena-poly[[[tetraaquacobalt(II)]-μ-2,2'-oxydiacetato-[dioxidouranium(VI)]-μ-2,2'-oxydiacetato] dihydrate], {[CoU(C4H4O5)2O2(H2O)4]·2H2O}n, both crystallize in the triclinic space group P-1...
August 1, 2017: Acta Crystallographica. Section C, Structural Chemistry
Stoyan Kamburov, Horst Schmidt, Wolfgang Voigt, Christo Balarew
Metal selenates crystallize in many instances in isomorphic structures of the corresponding sulfates. Sodium magnesium selenate decahydrate, Na2Mg(SeO4)2·10H2O, and sodium magnesium selenate dihydrate, Na2Mg(SeO4)2·2H2O, were synthesized by preparing solutions of Na2SeO4 and MgSeO4·6H2O with different molar ratios. The structures contain different Mg octahedra, i.e. [Mg(H2O)6] octahedra in the decahydrate and [MgO4(H2O)2] octahedra in the dihydrate. The sodium polyhedra are also different, i.e. [NaO2(H2O)4] in the decahydrate and [NaO6(H2O)] in the dihydrate...
July 1, 2017: Acta Crystallographica. Section C, Structural Chemistry
Philipp Kramer, Michael Bolte
Kryptoracemates are racemic compounds (pairs of enantiomers) that crystallize in Sohnke space groups (space groups that contain neither inversion centres nor mirror or glide planes nor rotoinversion axes). Thus, the two symmetry-independent molecules cannot be transformed into one another by any symmetry element present in the crystal structure. Usually, the conformation of the two enantiomers is rather similar if not identical. Sometimes, the two enantiomers are related by a pseudosymmetry element, which is often a pseudocentre of inversion, because inversion symmetry is thought to be favourable for crystal packing...
July 1, 2017: Acta Crystallographica. Section C, Structural Chemistry
Amanda M Holland, Allen G Oliver, Vlad M Iluc
The structure of a pincer ligand consists of a backbone and two `arms' which typically contain a P or N atom. They are tridentate ligands that coordinate to a metal center in a meridional configuration. A series of three iron complexes containing the pyrrole-based PNP pincer ligand 2,5-bis[(diisopropylphosphanyl)methyl]pyrrolide (PN(pyr)P) has been synthesized. These complexes are possible precursors to new iron catalysts. {2,5-Bis[(diisopropylphosphanyl)methyl]pyrrolido-κ(3)P,N,P'}carbonylchlorido(trimethylphosphane-κP)iron(II), [Fe(C18H34NP2)Cl(C3H9P)(CO)] or [Fe(PN(pyr)P)Cl(PMe3)(CO)], (I), has a slightly distorted octahedral geometry, with the Cl and CO ligands occupying the apical positions...
July 1, 2017: Acta Crystallographica. Section C, Structural Chemistry
Eleonora Freire, Gustavo A Echeverría, Ricardo Baggio
Two lamotriginium salts, namely lamotriginium crotonate [systematic name: 3,5-diamino-6-(2,3-dichlorophenyl)-1,2,4-triazin-2-ium but-2-enoate, C9H8Cl2N5(+)·C4H5O2(-), (III)] and lamotriginium salicylate [systematic name: 3,5-diamino-6-(2,3-dichlorophenyl)-1,2,4-triazin-2-ium 2-hydroxybenzoate ethanol monosolvate, C9H8Cl2N5(+)·C7H5O3(-)·C2H5OH, (IV)] present extremely similar centrosymmetric hydrogen-bonded A...L...L...A packing building blocks (L is lamotriginium and A is the anion). The fact that salicylate salt (IV) is (ethanol) solvated, while crotonate salt (III) is not, has a profound effect on the way these elemental units aggregate to generate the final crystal structure...
July 1, 2017: Acta Crystallographica. Section C, Structural Chemistry
Ewa Żesławska, Anna Jakubowska, Wojciech Nitek
Unnatural cyclic α-amino acids play an important role in the search for biologically active compounds and macromolecules. Enantiomers of natural amino acids with a D configuration are not naturally encoded, but can be chemically synthesized. The crystal structures of two enantiomers obtained by a method of stereoselective synthesis, namely (5R,8S)-8-tert-butyl-7-methoxy-8-methyl-9-oxa-6-azaspiro[4.5]decane-2,10-dione, (1), and (5S,8R)-8-tert-butyl-7-methoxy-8-methyl-9-oxa-6-azaspiro[4.5]decane-2,10-dione, (2), both C14H21NO4, were determined by X-ray diffraction...
July 1, 2017: Acta Crystallographica. Section C, Structural Chemistry
Fan Zhi Bu, Xue Jie Tan, Dian Xiang Xing, Chao Wang
A novel and potentially active dihydroorotate dehydrogenase (DHODH) inhibitor, namely 3-({(E)-[(E)-1-(biphenyl-4-yl)ethylidene]hydrazinylidene}methyl)-1H-indole (BEHI) acetonitrile disolvate, C23H19N3·2CH3CN, has been designed and synthesized. The structure of BEHI was characterized by elemental analysis, Q-TOF (quadrupole time-of-flight) MS, NMR, UV-Vis and single-crystal X-ray diffraction. The antitumour activity of the target molecule was evaluated by the MTT method. Results indicated that BEHI exhibited rather potent cytotoxic activity against human A549 (IC50 = 20...
July 1, 2017: Acta Crystallographica. Section C, Structural Chemistry
Hua Xie, Wang Jian Fang, Xiao Qiang Yao
One of the most interesting phenomena in coordination polymers (CPs) is the co-existence of different interlaced motifs. However, CPs having two different interlaced motifs at the same time are still rare. Colourless block-shaped crystals of the two-dimensional polymer poly[[aqua(μ2-naphthalene-2,6-dicarboxylato){μ2-4,4'-[oxybis(4,1-phenylene)]dipyridine}cadmium(II)] monohydrate], {[Cd(C12H6O4)(C22H16N2O)(H2O)]·H2O}n, (I), was synthesized under hydrothermal conditions by the self-assembly of 4,4'-[oxybis(4,1-phenylene)]dipyridine (OPY) with Cd(II) in the presence of naphthalene-2,6-dicarboxylic acid (H2ndc)...
July 1, 2017: Acta Crystallographica. Section C, Structural Chemistry
Marimuthu Mohana, Packianathan Thomas Muthiah, Ray J Butcher
Two new salts, namely 2,6-diamino-4-chloropyrimidinium 2-carboxy-3-nitrobenzoate, C4H6ClN4(+)·C8H4NO6(-), (I), and 2,6-diamino-4-chloropyrimidinium p-toluenesulfonate monohydrate, C4H6ClN4(+)·C7H7O3S(-)·H2O, (II), have been synthesized and characterized by single-crystal X-ray diffraction. In both crystal structures, the N atom in the 1-position of the pyrimidine ring is protonated. In salt (I), the protonated N atom and the amino group of the pyrimidinium cation interact with the carboxylate group of the anion through N-H...
July 1, 2017: Acta Crystallographica. Section C, Structural Chemistry
John M Moore, Jasmine M Hall, Wendell L Dilling, Anton W Jensen, Philip J Squattrito, Patrick Giolando, Kristin Kirschbaum
3-Aminocarbonyl-1-benzylpyridinium bromide (N-benzylnicotinamide, BNA), C13H13N2O(+)·Br(-), (I), and 1-benzyl-1,4-dihydropyridine-3-carboxamide (N-benzyl-1,4-dihydronicotinamide, rBNA), C13H14N2O, (II), are valuable model compounds used to study the enzymatic cofactors NAD(P)(+) and NAD(P)H. BNA was crystallized successfully and its structure determined for the first time, while a low-temperature high-resolution structure of rBNA was obtained. Together, these structures provide the most detailed view of the reactive portions of NAD(P)(+) and NAD(P)H...
July 1, 2017: Acta Crystallographica. Section C, Structural Chemistry
Khai Nghi Truong, Niklas Lothmann, Ulli Englert
Depending on the reaction partner, the organic ditopic molecule isonicotinic acid (Hina) can act either as a Brønsted acid or base. With sulfuric acid, the pyridine ring is protonated to become a pyridinium cation. Crystallization from ethanol affords the title compound tris(4-carboxypyridinium) hydrogensulfate sulfate monohydrate, 3C6H6NO2(+)·HSO4(-)·SO4(2-)·H2O or [(H2ina)3(HSO4)(SO4)(H2O)]. This solid contains 11 classical hydrogen bonds of very different flavour and nonclassical C-H...O contacts. All N-H and O-H donors find at least one acceptor within a suitable distance range, with one of the three pyridinium H atoms engaged in bifurcated N-H...
July 1, 2017: Acta Crystallographica. Section C, Structural Chemistry
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