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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
Fatih Şen, Sevgi Kansiz, İbrahim Uçar
Transition metal atoms can be bridged by aliphatic dicarboxylate ligands to produce chains, layers and frameworks. The reaction of copper sulfate with succinic acid (H2succ) and N,N-diethylethylenediamine (deed) in basic solution produces the complex catena-poly[[[(N,N-diethylethylenediamine-κ(2)N,N')copper(II)]-μ-succinato-κ(2)O(1):O(4)] tetrahydrate], {[Cu(C4H4O4)(C6H16N2)]·4H2O}n or {[Cu(succ)(deed)]·4H2O}n. Each carboxylate group of the succinate ligand coordinates to a Cu(II) atom in a monodentate fashion, giving rise to a square-planar coordination environment...
July 1, 2017: Acta Crystallographica. Section C, Structural Chemistry
Fahimeh Sabbaghi, Mehrdad Pourayoubi, Abolghasem Farhadipour, Nazila Ghorbanian, Pavel V Andreev
In the structure of 2-(4-chloroanilino)-1,3,2λ(4)-diazaphosphol-2-one, C12H11ClN3OP, each molecule is connected with four neighbouring molecules through (N-H)2...O hydrogen bonds. These hydrogen bonds form a tubular arrangement along the [001] direction built from R(3)3(12) and R4(3)(14) hydrogen-bond ring motifs, combined with a C(4) chain motif. The hole constructed in the tubular architecture includes a 12-atom arrangement (three P, three N, three O and three H atoms) belonging to three adjacent molecules hydrogen bonded to each other...
July 1, 2017: Acta Crystallographica. Section C, Structural Chemistry
Long Tang, Juan Zhang, Xiao Xia Liu, Ji Jiang Wang, Feng Fu
The reaction of Cu(NO3)2·3H2O with 2,4'-oxybis(benzoic acid) and 4,4'-bipyridine under hydrothermal conditions produced a new mixed-ligand two-dimensional copper(II) coordination polymer, namely poly[[(μ-4,4'-bipyridine-κ(2)N,N')[μ-2,4'-oxybis(benzoato)-κ(4)O(2),O(2'):O(4),O(4')]copper(II)] monohydrate], {[Cu(C14H8O5)(C10H8N2)]·H2O}n, which was characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis and single-crystal X-ray diffraction. The X-ray diffraction crystal structure analysis reveals that the Cu(II) ions are connected to form a two-dimensional wave-like network through 4,4'-bipyridine and 2,4'-oxybis(benzoate) ligands...
July 1, 2017: Acta Crystallographica. Section C, Structural Chemistry
Wei Wei Fu, Juan Li, Shu Ting Liu, Dan Zhao, Xue Zhou, Yang Tong
The bifunctional pyridine-2,3-dicarboxylic acid (H2pdc) ligand has one N atom and four O atoms, which could bind more than one Ag(I) centre with diverse binding modes. A novel infinite one-dimensional Ag(I) coordination polymer, namely catena-poly[[silver(I)-(μ2-pyridine-2,3-dicarboxylato-κ(2)N:O(3))-silver(I)-tris(μ2-5-methyl-1,3,4-thiodiazol-2-amine-κ(2)N:N')] monohydrate ethanol monosolvate], {[Ag2(C7H3NO4)(C3H5N3S)3]·H2O·C2H5OH}n, has been synthesized using H2pdc and 5-methyl-1,3,4-thiadiazol-2-amine (tda), and characterized by single-crystal X-ray diffraction...
June 1, 2017: Acta Crystallographica. Section C, Structural Chemistry
S S Anjana, Babu Varghese, Edamana Prasad
Phosphate esters provide a rigid and stable polymeric backbone in nucleic acids. Metal complexes with phosphate ester groups have been synthesized as structural and spectroscopic models of phosphate-containing enzymes. Dinucleating ligands are used extensively to synthesize model complexes since they provide the support required to stabilize such complexes. The crystal structures of two dinuclear Co(II) complexes, namely bis(μ-diphenyl phosphato-κ(2)O:O')bis({2-methoxy-N,N-bis[(pyridin-2-yl)methyl]aniline-κ(4)N,N',N'',O}cobalt(II)) bis(perchlorate), [Co(C12H10O4P)2(C19H19N3O)2](ClO4)2, and bis(μ-diphenyl phosphato-κ(2)O:O')bis({N,N-bis[(pyridin-2-yl)methyl]quinolin-8-amine-κ(4)N,N',N'',O}cobalt(II)) bis(perchlorate), [Co(C12H10O4P)2(C21H18N4)2](ClO4)2, with tetradentate 2-methoxy-N,N-bis[(pyridin-2-yl)methyl]aniline (L(1)) and N,N-bis[(pyridin-2-yl)methyl]quinolin-8-amine (L(2)) ligands are reported...
June 1, 2017: Acta Crystallographica. Section C, Structural Chemistry
Rong Er Shou, Li Song, Wen Xiang Chai, Lai Shun Qin, Tian Gen Wang
Luminescent Cu(I) complexes have emerged as promising substitutes for phosphorescent emitters based on Ir, Pt and Os due to their abundance and low cost. The title heteroleptic cuprous complex, [9,9-dimethyl-4,5-bis(diphenylphosphanyl)-9H-xanthene-κ(2)P,P](2-methylquinolin-8-ol-κ(2)N,O)copper(I) hexafluorophosphate, [Cu(C10H9NO)(C39H32OP2)]PF6, conventionally abbreviated as [Cu(Xantphos)(8-HOXQ)]PF6, where Xantphos is the chelating diphosphine ligand 9,9-dimethyl-4,5-bis(diphenylphosphanyl)-9H-xanthene and 8-HOXQ is the N,O-chelating ligand 2-methylquinolin-8-ol that remains protonated at the hydroxy O atom, is described...
June 1, 2017: Acta Crystallographica. Section C, Structural Chemistry
Marimuthu Mohana, Packianathan Thomas Muthiah, Colin D McMillen
In solid-state engineering, cocrystallization is a strategy actively pursued for pharmaceuticals. Two 1:1 cocrystals of 5-fluorouracil (5FU; systematic name: 5-fluoro-1,3-dihydropyrimidine-2,4-dione), namely 5-fluorouracil-5-bromothiophene-2-carboxylic acid (1/1), C5H3BrO2S·C4H3FN2O2, (I), and 5-fluorouracil-thiophene-2-carboxylic acid (1/1), C4H3FN2O2·C5H4O2S, (II), have been synthesized and characterized by single-crystal X-ray diffraction studies. In both cocrystals, carboxylic acid molecules are linked through an acid-acid R2(2)(8) homosynthon (O-H...
June 1, 2017: Acta Crystallographica. Section C, Structural Chemistry
Rikako Tanaka, Nobuyuki Matsushita
The methyl viologen dication, used under the name Paraquat as an agricultural reagent, is a well-known electron-acceptor species that can participate in charge-transfer (CT) interactions. The determination of the crystal structure of this species is important for accessing the CT interaction and CT-based properties. The title hydrated salt, bis(1,1'-dimethyl-4,4'-bipyridine-1,1'-diium) hexacyanidoferrate(II) octahydrate, (C12H14N2)2[Fe(CN)6]·8H2O or (MV)2[Fe(CN)6]·8H2O [MV(2+) is the 1,1'-dimethyl-4,4'-bipyridine-1,1'-diium (methyl viologen) dication], crystallizes in the space group P21/c with one MV(2+) cation, half of an [Fe(CN)6](4-) anion and four water molecules in the asymmetric unit...
June 1, 2017: Acta Crystallographica. Section C, Structural Chemistry
Pei Ying Guo, De Yun Ma, Hai Fu Guo
The 2-methylbiphenyl-4,4'-dicarboxylate (mbpdc(2-)) ligand has versatile coordination modes and can be used to construct multinuclear structures. Despite this, reports of the synthesis of coordination complexes involving this ligand are scarce. The title compound, poly[[triaquadi-μ3-hydroxido-hexakis(μ4-2-methylbiphenyl-4,4'-dicarboxylato)calcium(II)hexazinc(II)] monohydrate], {[CaZn6(C15H10O4)6(OH)2(H2O)3]·H2O}n, has been prepared by the hydrothermal assembly of Zn(NO3)2·6H2O, CaCl2 and 2-methylbiphenyl-4,4'-dicarboxylic acid...
June 1, 2017: Acta Crystallographica. Section C, Structural Chemistry
Juan Liu, Yang Rong Xu, Xing Si An, Gui Ge Hou, Qing Guo Meng
In order to study the in vivo protective effect on myocardial ischemia, (20S,24R)-epoxydammarane-12β,25-diol, (V), and (20S,24S)-epoxydammarane-12β,25-diol, (VI), were synthesized through a novel synthetic route. Two key intermediates, namely (20S,24R)-3-acetyl-20,24-epoxydammarane-3β,12β,25-triol, (III) [obtained as the hemihydrate, C32H54O5·0.5H2O, (IIIa), and the ethanol hemisolvate, C32H54O5·0.5C2H5OH, (IIIb), with identical conformations but different crystal packings], and (20S,24S)-3-acetyl-20,24-epoxydammarane-3β,12β,25-triol, C32H54O5, (IV), were obtained during the synthesis...
June 1, 2017: Acta Crystallographica. Section C, Structural Chemistry
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