Two types of Ln2Cu2 hydroxo-trimethylacetate complexes with 0D and 1D motifs: synthetic features, structural differences, and slow magnetic relaxation

2021 ◽  
Author(s):  
Anna Bovkunova ◽  
Evgeniya S. Bazhina ◽  
Igor Evstifeev ◽  
Yulia V. Nelyubina ◽  
Maxim Shmelev ◽  
...  
Keyword(s):  
Magnetic Relaxation ◽  
X Ray Diffraction ◽  
Metal Core ◽  
X Ray ◽  
Trimethylacetate Complexes ◽  
Structural Differences ◽  
Slow Magnetic Relaxation ◽  
New Compounds

Two series of heterometallic LnIII−CuII compounds containing a butterfly-like tetranuclear metal core were synthesized and characterized by X-ray diffraction and magnetometry. The structures of the new compounds were shown to...

Goblet-shaped pentanuclear lanthanide clusters assembled with a cyclen derivative ligand exhibiting slow magnetic relaxation

2016 ◽  
Vol 45 (32) ◽  
pp. 12734-12738 ◽  
Author(s):  
Gaoji Wang ◽  
Yongqin Wei ◽  
Kechen Wu
Keyword(s):  
Single Crystal ◽  
Magnetic Relaxation ◽  
Magnetic Study ◽  
X Ray Diffraction ◽  
X Ray ◽  
Slow Magnetic Relaxation ◽  
Ferromagnetic Interactions

Two goblet-shaped 5Ln clusters have been assembled. Single-crystal X-ray diffraction studies reveal that both compounds feature a novel homometallic appended cubane geometry. The magnetic study on 1 suggests the presence of anti-ferromagnetic interactions, whereas 2 exhibits SMM behavior.

Field-induced slow magnetic relaxation in mixed valence di- and tri-nuclear CoII–CoIII complexes

2020 ◽  
Vol 49 (27) ◽  
pp. 9516-9528 ◽  
Author(s):  
Aparup Paul ◽  
Marta Viciano-Chumillas ◽  
Horst Puschmann ◽  
Joan Cano ◽  
Subal Chandra Manna
Keyword(s):  
Low Temperature ◽  
Single Crystal ◽  
Magnetic Relaxation ◽  
Mixed Valence ◽  
X Ray Diffraction ◽  
Magnetic Studies ◽  
X Ray ◽  
Slow Magnetic Relaxation

Two novel mixed valence di/tri nuclear CoII–CoIII complexes were synthesized and characterized by single crystal X-ray diffraction. Magnetic studies at low temperature revealed that both complexes show slow magnetic relaxation.

Synthese und Kristallstrukturen einiger Tetramethylstibonium-Hydrogendicarboxylate / Synthesis and Crystal Structures of Some Tetramethylstibonium Hydrogendicarboxylates

1982 ◽  
Vol 37 (11) ◽  
pp. 1393-1401 ◽  
Author(s):  
Beatrix Milewski-Mahrla ◽  
Hubert Schmidbaur
Keyword(s):  
Hydrogen Bonds ◽  
Crystal Structures ◽  
Spectroscopic Data ◽  
Molar Ratio ◽  
Ionic Structure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Carboxylate Oxygen ◽  
Donor Acceptor ◽  
New Compounds

Reactions of pentamethylantimony (CH3)5Sb with carboxylic acids in the molar ratio 1:2 afford one equivalent of methane and essentially quantitative yields of crystalline tetramothylstibonium hydrogendicarboxylates. Six new compounds of this series have been synthesized using benzoic, o-phthalic, salicylic, 4-ethoxy-salicylic, oxalic, and malic acid, and characterized by analytical and spectroscopic data. An ionic structure with strong hydrogen bonds in the anionic components is proposed.The crystal structures of the hydrogen-dibenzoato (1), hydrogen-ortho-plithalato (2) and 4-ethoxy-hydrogen-salicylate (3) were determined by single crystal X-ray diffraction. The compounds can be described as having ionic lattices with some donor-acceptor inter­actions between the stibonium centers and the carboxylate oxygen atoms. The anions are characterized by strong hydrogen bonds O...H...O. Thus, the (CH3)4Sb-tetrahedron in 1 is distorted by two benzoate oxygon atoms (at 304(2) and 340(2) pin). The cation in 2 is largely undistorted and the anion has a hydrogenphthalate hydrogen bond of d(O...H...O) = 232 pm. The cation-anion contact in 3 is as short as d(Sb-O) = 289 pm rendering the Sb atom pentacoordinate.

scholarly journals Crystallization and preliminary crystallographic analysis of manganese lipoxygenase

2014 ◽  
Vol 70 (4) ◽  
pp. 522-525 ◽  
Author(s):  
Anneli Wennman ◽  
Ernst H. Oliw ◽  
Saeid Karkehabadi
Keyword(s):  
Expression System ◽  
Crystallographic Analysis ◽  
Gaeumannomyces Graminis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cell Parameters ◽  
Apparent Homogeneity ◽  
Structural Differences ◽  
Position Specificity ◽  
Take All

Lipoxygenases constitute a family of nonhaem metal enzymes with catalytic iron or, occasionally, catalytic manganese. Lipoxygenases oxidize polyunsaturated fatty acids with position specificity and stereospecificity to hydroperoxides, which contribute to inflammation and the development of cancer. Little is known about the structural differences between lipoxygenases with Fe or Mn and the metal-selection mechanism. APichia pastorisexpression system was used for the production of the manganese lipoxygenase of the take-all fungus of wheat,Gaeumannomyces graminis. The active enzyme was treated with α-mannosidase, purified to apparent homogeneity and subjected to crystal screening and X-ray diffraction. The crystals diffracted to 2.6 Å resolution and belonged to space groupC2, with unit-cell parametersa= 226.6,b= 50.6,c= 177.92 Å, β = 91.70°.

Four New Cytotoxic Arborinane-Type Triterpenes from the Endolichenic Fungus Myrothecium inundatum

Planta Medica ◽  
2019 ◽  
Vol 85 (09/10) ◽  
pp. 701-707 ◽  
Author(s):  
Buddha Bahadur Basnet ◽  
Li Liu ◽  
Baosong Chen ◽  
Yerlan Melsuly Suleimen ◽  
Haiyang Yu ◽  
...  
Keyword(s):  
Absolute Configuration ◽  
Ethyl Acetate Extract ◽  
Human Cancer ◽  
Diffraction Experiment ◽  
Human Cancer Cell ◽  
X Ray Diffraction ◽  
X Ray ◽  
Human Cancer Cell Lines ◽  
Endolichenic Fungus ◽  
New Compounds

AbstractTwo new arborinane-type triterpenes, myrotheols A (1) and B (2), two new arborinane-type glycosides, myrothesides C (3) and D (4), together with four known diterpenes (5 – 8) were isolated from the ethyl acetate extract of the endolichenic fungus Myrothecium inundatum. The structures of new compounds 1 – 4 were elucidated by NMR and MS analyses. The absolute configuration of 1 was assigned by a single-crystal X-ray diffraction experiment. Compounds 3 and 4 represent the first two natural 4-O-methyl-α-D-mannosides. Compounds 1 – 8 exhibited cytotoxicity against K562 and RKO human cancer cell lines.

Isolation and structures of the uprolides. I. Thirteen new cytotoxic cembranolides from the Caribbean gorgonian Euniceamammosa

1995 ◽  
Vol 73 (5) ◽  
pp. 643-654 ◽  
Author(s):  
Abimael D. Rodríguez ◽  
Ivette C. Piña ◽  
Javier J. Soto ◽  
Dalila R. Rojas ◽  
Charles L. Barnes
Keyword(s):  
Nuclear Magnetic Resonance Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Correlation Studies ◽  
Resonance Analysis ◽  
Eupalmerin Acetate ◽  
Chemical Correlation ◽  
The Caribbean ◽  
New Compounds

Thirteen new cembranolide diterpenoids, uprolides 3–15, have been isolated from the Caribbean gorgonian Euniceamammosa collected off the West coast of Puerto Rico. Several known metabolites, such as eupalmerin acetate (1) and eupalmerin (2), were also isolated from the same organism. The structures of the new compounds, which also showed modest in vitro cytotoxic activity, were assigned on the basis of extensive nuclear magnetic resonance analysis, chemical correlation studies, and by comparison with analogous spectral data from known cembranolide diterpenoids. One structure (3) was confirmed by X-ray diffraction analysis. Keywords: uprolides, Euniceamammosa, cytotoxicity, Caribbean, gorgonian.

Structural Characterization of a Series of New Ternary η-Nitride Compounds

1997 ◽  
Vol 495 ◽  
Author(s):  
K. S. Weil ◽  
P. N. Kumta
Keyword(s):  
Structural Characterization ◽  
X Ray Diffraction ◽  
X Ray ◽  
Synthesis Route ◽  
Precursor Synthesis ◽  
Structural Differences ◽  
Cubic Structure ◽  
Ternary Nitride

ABSTRACTThe structures of four new tungsten based, ternary nitride compounds, Fe3W3N, Ni6W6N, Ni2W4N, and Fe4W2N, each prepared using a complexed precursor synthesis route, have been determined by Rietveld analyses of the respective powder x-ray diffraction (PXRD) data. Each compound crystallizes in a relatively complex cubic structure which is in general isostructural with the η-carbide structure. However, subtle structural differences which are compositionally dependent do exist between each nitride and these will be examined in detail in this paper.

Crystal Structures of New Compounds Na0.5Sm4.5Ti4O15 and Na0.5Eu4.5Ti4O15

2011 ◽  
Vol 415-417 ◽  
pp. 468-471
Author(s):  
Qiao Hong Yu ◽  
Zheng Fa Li ◽  
Yong Xiang Li ◽  
Ping Zhan Si ◽  
Jiang Ying Wang ◽  
...  
Keyword(s):  
Solid State ◽  
Crystal Structures ◽  
Powder Diffraction ◽  
Diffraction Data ◽  
Diffraction Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ordinary Temperature ◽  
Europium Titanate ◽  
New Compounds

New compounds of sodium samarium titanate Na0.5Sm4.5Ti4O15and sodium europium titanate Na0.5Eu4.5Ti4O15were synthesized successfully by solid state reaction at 1300 oC and 1200 oC, respectively. The lattice parameters of Na0.5Sm4.5Ti4O15and Na0.5Eu4.5Ti4O15were determined at ordinary temperature by using X-ray powder diffraction method. Their Lattice types were determined, and their patterns were indexed. Polycrystalline X-ray diffraction data of sodium samarium titanate were listed. Differences of their crystal structures were analyzed and discussed.

AlkalineEarthMetal-Hydride-Iodide Compounds: Syntheses andCrystal Structures of Sr2H3I and Ba5H2I3.9(2)O2

2011 ◽  
Vol 66 (1) ◽  
pp. 21-26
Author(s):  
Olaf Reckeweg ◽  
Francis J. DiSalvo
Keyword(s):  
Single Crystal ◽  
Single Crystals ◽  
Structural Model ◽  
Structure Type ◽  
Lattice Parameters ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray ◽  
New Compounds

Single crystals of Sr2H3I andBa5H2I3.9(2)O2 were obtained by reacting Sr or Ba, respectively, with dried and sublimed NH4I in a 4 : 1 molar ratio in silica-jacketed Nb ampoules for 13 h at 1200 K. The crystal structures of the new compounds have been determined by means of single-crystal X-ray diffraction. Sr2H3I crystallizes in a stuffed anti-CdI2 structure isotypic to Ba2H3Cl in the space group P3m1 (no. 164) with the lattice parameters a = 426.0(1) and c = 774.9(2) pm, while Ba5H2I3.9(2)O2 crystallizes in a new structure type in the space group Cmcm (no. 63) with the lattice parameters a = 1721.0(2), b = 1452.5(2) and c = 639.03(9) pm. The structural results for Sr2H3I are corroborated by EUTAX calculations. For the disordered compound Ba5H2I3.9(2)O2, EUTAX calculations on an approximated, ordered structural model were used to find possible insights into the disorder

X-ray powder diffraction data for two new compounds (NH4)1.5Ni2V2O7(OH)1.5 · H2O and (NH4)1.5Cu1.125Ni1.125V2O7(OH)2 · H2O

2011 ◽  
Vol 26 (S1) ◽  
pp. S51-S54
Author(s):  
Johana Arboleda ◽  
Adriana Echavarría
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Thermogravimetric Analysis ◽  
Powder Diffraction ◽  
Diffraction Data ◽  
Powder Diffraction Data ◽  
X Ray Diffraction ◽  
X Ray ◽  
New Compounds ◽  
Scanning Electron

Two new bimetallic and trimetallic compounds (NH4)1.5Ni2V2O7(OH)1.5 · H2O and (NH4)1.5Cu1.125 Ni1.125V2O7(OH)2 · H2O were synthesized by hydrothermal method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and X-Ray fluorescence (XRF). Crystallographic studies showed that both compounds are hexagonal with space group P-62c.

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