Search results for "Pyrazine"
showing 10 items of 325 documents
CCDC 2026744: Experimental Crystal Structure Determination
2021
Related Article: Paul Richardson, Riccardo Marin, Yixin Zhang, Bulat Gabidullin, Jeffrey Ovens, Jani O. Moilanen, Muralee Murugesu|2020|Chem.-Eur.J.|27|2361|doi:10.1002/chem.202003556
CCDC 787111: Experimental Crystal Structure Determination
2011
Related Article: R.Gheorge, M.Kalisz, R.Clerac, C.Mathoniere, P.Herson, Yanling Li, M.Seuleiman, R.Lescouezec, F.Lloret, M.Julve|2010|Inorg.Chem.|49|11045|doi:10.1021/ic1015725
CCDC 1443218: Experimental Crystal Structure Determination
2016
Related Article: Livia Arizaga, Ricardo González, Donatella Armentano, Giovanni De Munno, Miguel A. Novak, Francesc Lloret, Miguel Julve, Carlos Kremer and Raúl Chiozzone|2016|Eur.J.Inorg.Chem.||1835|doi:10.1002/ejic.201501487
CCDC 1826069: Experimental Crystal Structure Determination
2019
Related Article: Nico Röder, Tomasz Marszalek, Daniel Limbach, Wojciech Pisula, Heiner Detert|2019|ChemPhysChem|20|463|doi:10.1002/cphc.201800936
A Switchable Molecular Rotator: Neutron Spectroscopy Study on a Polymeric Spin-Crossover Compound
2012
A quasielastic neutron scattering and solid-state 2H NMR spectroscopy study of the polymeric spin-crossover compound {Fe(pyrazine)[Pt(CN) 4]} shows that the switching of the rotation of a molecular fragment-the pyrazine ligand-occurs in association with the change of spin state. The rotation switching was examined on a wide time scale (10 -13-10 -3 s) by both techniques, which clearly demonstrated the combination between molecular rotation and spin-crossover transition under external stimuli (temperature and chemical). The pyrazine rings are seen to perform a 4-fold jump motion about the coordinating nitrogen axis in the high-spin state. In the low-spin state, however, the motion is suppres…
Ferromagnetic Coupling Through the End-to-End Thiocyanate Bridge in Cobalt(II) and Nickel(II) Chains
2015
The preparation, spectroscopic characterization, and X-ray crystal structure of two novel one-dimensional compounds of formula [MII(tppz)(NCS)(μ-1,3-NCS)]n [tppz = 2,3,5,6-tetrakis(2-pyridyl)pyrazine and M = Co(1) and Ni (2)] are reported. 1 and 2 are isomorphous compounds, and they crystallize in the P21/n space group. Their structures are made up of zigzag chains of cobalt(II) (1) and nickel(II) ions (2) bridged by single end-to-end thiocyanate groups with a tridentate tppz molecule and a terminally bound thiocyanate-N ligand achieving distorted MN5S octahedral surroundings around each metal center. The main source of the distortion of the ideal octahedron is due to the geometrical constr…
Syntheses, crystal structures and magnetic properties of copper(II) polynuclear and dinuclear compounds with 2,3-bis(2-pyridyl)pyrazine (dpp) and pse…
2001
Abstract The preparation, crystal structures and magnetic properties of four heteroleptic copper(II) complexes with 2,3-bis(2-pyridyl)pyrazine (dpp) and azide, cyanate or thiocyanate as ligands are reported, [Cu(dpp)(N3)2]n (1), [Cu(dpp)(NCO)2]n (2), [Cu(dpp)(NCS)2]2 (3) and [Cu(H2O)(dpp)(NCS)2]2·2H2O (4). Compounds 1 and 2 are isomorphous, triclinic, space group P1, and consist of mononuclear building blocks featuring copper atoms with close to square planar coordination geometries. The mononuclear units are, however, associated into chains through weak axial Cu–N bonds formed by end-on asymmetrically bridging azido/cyanato groups and by pyridyl nitrogen atoms. Taking these contacts into a…
Discovery and validation of small-molecule heat-shock protein 90 inhibitors through multimodality molecular imaging in living subjects.
2012
Up-regulation of the folding machinery of the heat-shock protein 90 (Hsp90) chaperone protein is crucial for cancer progression. The two Hsp90 isoforms (α and β) play different roles in response to chemotherapy. To identify isoform-selective inhibitors of Hsp90(α/β)/cochaperone p23 interactions, we developed a dual-luciferase (Renilla and Firefly) reporter system for high-throughput screening (HTS) and monitoring the efficacy of Hsp90 inhibitors in cell culture and live mice. HTS of a 30,176 small-molecule chemical library in cell culture identified a compound, N -(5-methylisoxazol-3-yl)-2-[4-(thiophen-2-yl)-6-(trifluoromethyl)pyrimidin-2-ylthio]acetamide (CP9), that binds to Hsp90(α/β) an…
Relationship between XPS core binding energies and atomic charge in adducts of SnIV derivatives with pyrazine, and comparison with mössbauer isomer s…
1981
Abstract Adducts Snhal·pyz (hal = Cl, Br, I; pyz = pyrazine), RnSnCl 4−n ·pyz (n = 1, R = Me, Bu n , Oct n , Ph; n = 2, R = Ph) and SnCl 4 ·(pyz) 2 have been investigated by X-ray photoelectron spectroscopy. Binding energy (b.e.) values are discussed in the light of structural characteristics of the adducts as well as of valence state electronegativities of atoms and groups bound to tin. Sn 3d 5 2 b.e.s, corrected for the Madelung potential at the metal atom, linearly correlate with both partial atomic charges on tin, accounting for relaxation upon ionization, and 119 Sn Mossbauer isomer shifts. The results are interpreted in terms of six-coordinated, octahedral type, configurations of the …
[1,2,3]Triazoloazine/(Diazomethyl)azine Valence Tautomers from 5-Azinyltetrazoles
1978
[1,2,3]Triazoloazines are formed by thermolysis of 5-azinyltetrazoles in the gasphase or in solution. Thus, 5-(2-pyridyl)tetrazole (7) and 5-(2-pyrazinyl)tetrazole (11) yield [1,2,3]triazolo[1,5-a]pyridine (9) and [1,2,3]triazolo[1,5-a]pyrazine (13), respectively, at 400°/10−3 - 10−5 Torr. 5-(2-Phenyl-4-quinazolinyl)tetrazole (15) gives 5-phenyl[1,2,3]triazolo[1,5-c]quinazoline (17) in 75% yield by heating under reflux in mesitylene solution. 2-(Diazomethyl)pyridine (8), a valence tautomer of 9, can be trapped by fumaronitrile, leading to 3-(2-pyridyl)-1, 2-cyclopropanedicarbonitrile (19). The [1,2,3]triazoloazines undergo base catalysed H/D-exchange in D2O solution.