Search results for "Crystal Structure"

showing 10 items of 15036 documents

Novel [6]- and [7]Helicene-Like Quinones via Mono- and Bidirectional Chromium-Templated Benzannulation of Bridged Binaphthyl Carbene Complexes

2005

A new organometallic approach to novel, functionalised, helicene-like quinones and bisquinones has been developed based on the chromium-templated [3+2+1] benzannulation reaction. The [5]helicene-analogous monocarbene chromium complexes 4, 5, 17 and 19, derived from dibromo-substituted methylene- or silylene-tethered binaphthols 2 and 3, react with various alkynes to give [6]helicene-like quinones 6–13 and 20–29 after oxidative work-up. A rare competition of angular vs. linear annulation is observed for the incorporation of phenylacetylene that affords quinones 21/22 and 28/29. Protection of the phenolic benzannulation product with camphanic acid chloride 14, followed by chromatographic sepa…

AnnulationChemistryStereochemistryArylOrganic ChemistryCrystal structureMedicinal chemistrychemistry.chemical_compoundEnantiopure drugHelicenePhenylacetylenePhysical and Theoretical ChemistryMethyleneCarbeneEuropean Journal of Organic Chemistry
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2015

The heterotetracene skeleton of the title molecule, C23H14Br2N2OS, is defined by linear annulation of four six-membered rings, including two N heteroatoms. This moiety is nearly planar (r.m.s. deviation = 0.055 Å), with a slight twist of 4.1 (2)° between the two halves of the aromatic system. The dihedral angle between the least-squares plane of the skeleton and the benzyl group is 24.5 (3)°; the C—S—C angle involving the benzylsulfanyl group is 99.2 (4)°. In the crystal, molecules are π-stacked in an antiparallel fashion along [110], with a distance between the aromatic planes of 3.47 (2) Å. Intermolecular N—H...O hydrogen bonds form chains extending parallel to [001] and bridge the antipa…

AnnulationHydrogen bondChemistryHeteroatomGeneral ChemistryCrystal structureDihedral angleCondensed Matter PhysicsBioinformaticschemistry.chemical_compoundCrystallographySulfanylBenzyl groupMoietyGeneral Materials ScienceActa Crystallographica Section E Crystallographic Communications
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Synthesis, characterization and the first crystal structure of the Zn(II) complex of 4,6-O-ethylidine-N-(2-hydroxybenzylidene)-β-D-glucopyranosylamine

2001

4,6-O-Ethylidine-N-(2-hydroxybenzylidene)-β-D-glucopyranosylamine (H3L1) and N-(5-bromo-2-hydroxybenzylidene-4,6-O-ethylidine-β-D-glucopyranosylamine (H3L2) molecules possessing a–C-1–N=C(H)–moiety for metal-ion binding were synthesized by condensing the 4,6–O–ethylidene–β–D–glucopyranosylamine with salicylaldehyde or 5–bromosalicylaldehyde. Complexes of these ligands with Zn(II) were isolated and characterized using elemental analysis, FTIR, UV–Vis absorption, NMR spectroscopic and FAB mass spectrometric techniques. The structure of the Zn(II) complex derived from H3L1 was established for the first time by a single-crystal X-ray diffraction study. The anomeric nature of the saccharide moie…

AnomerMagnetic Resonance SpectroscopyStereochemistrySynthesis (Chemical)Crystal structureCrystallography X-RayLigandsBiochemistryMass SpectrometryAnalytical Chemistrychemistry.chemical_compoundX-Ray DiffractionOrganometallic CompoundsMoietyMoleculeFourier transform infrared spectroscopyGlucosamineMolecular StructureLigandChemistryOrganic ChemistryGeneral MedicineCrystallographyZincSalicylaldehydeProton NMRCrystal StructureSpectrophotometry UltravioletComplexationIndraStra Global
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Thermodynamic and fluorescence emission studies on chemosensors containing anthracene fluorophores. Crystal structure of {[CuL1Cl]Cl}2·2H2O [L1 = N-(…

1999

The co-ordination capabilities toward hydrogen ions, Co2+, Ni2+, Cu2+, Zn2+ and Cd2+ of the novel receptor 2,6,9,13-tetraaza[14](9,10)anthracenophane (L) and of its open-chain counterpart N-(3-aminopropyl)-N′-3-(anthracen-9-ylmethyl)aminopropylethane-1,2-diamine (L1) is described. Stepwise protonation constants of the cyclic receptor (L) are lower than those of the open-chain receptor (L1) . Quenching effects of the fluorescence emission occur upon first and second deprotonation of L and upon second deprotonation of L1. Stability constants of the Co2+, Ni2+, Cu2+, Zn2+ and Cd2+ complexes follow the Irving–Williams trend and are intermediate between those of triethylenetetraamine with termin…

Anthracenechemistry.chemical_compoundCrystallographyDeprotonationQuenching (fluorescence)chemistrySquare pyramidProtonationGeneral ChemistryCrystal structureTriclinic crystal systemPhotochemistrySquare pyramidal molecular geometry
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Synthesis and structural elucidation of novel antifungal N-(fluorophenyl)piperazinyl benzoxaboroles and their analogues

2019

Abstract Series of novel N-(fluorophenyl)piperazine derivatives of phenylboronic compounds including benzoxaboroles, phenylboronic acids and phenylboronic methyl monoester have been obtained by facile synthetic methods starting from 2-formylphenylboronic acid. Molecular and crystal structures of those novel derivatives have been investigated by single crystal X-ray diffraction method. The Bond Valence Vector Model was used to describe strains in the boron coordination sphere. Microbiological activity of novel benzoxaboroles as well as their corresponding acid analogues against: A. niger, A. terreus, P. ochrochloron, C. tenuis and F. dimerum has been evaluated. The presence of heterocyclic b…

AntifungalorganoboronValence (chemistry)Coordination sphere010405 organic chemistryChemistrymedicine.drug_classphenylboronic acidantifungal activityOrganic ChemistrybenzoxaboroleCrystal structurepiperazine010402 general chemistry01 natural sciencesCombinatorial chemistryfluorophenyl0104 chemical sciencesAnalytical ChemistryInorganic Chemistrychemistry.chemical_compoundPiperazinemedicinePhenylboronic acidSpectroscopyJournal of Molecular Structure
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Structure and Phase Transitions in Ethylenediammonium Dichloride and its Salts with Antimony Trichloride

2000

During the mixing of ethylenediammonium dichloride and antimony trichloride except of reported earlier [NH3(CH2)2NH3]5(Sb2Cl11)2 · 4 H2O a new salt [NH3(CH2)2NH3](SbCl4)2 was obtained. The crystals are monoclinic at 295 K, space group C2/m, a = 13.829(3), b = 7.408(1), c = 7.588(2) A; β = 103.18(3)°; V = 756.9(3) A3; Z = 2; dc = 2.585, dm = 2.56(2) g · cm–3. The structure consists of anionic sublattice built of Sb2Cl82– units composed of two SbCl52– square pyramids connected by edge. The ethylenediammonium cations are located in anionic cavities. The cations are disordered. Each methylene carbon atom is split between two positions. The X-ray diffraction, DSC, TGA and dilatometric methods we…

Antimony trichloridePhase transitionCarbon atomChemistrychemistry.chemical_elementCrystal structureFirst orderInorganic Chemistrychemistry.chemical_compoundCrystallographyAntimonyPolymer chemistryMethyleneMonoclinic crystal systemZeitschrift für anorganische und allgemeine Chemie
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CCDC 113469: Experimental Crystal Structure Determination

2000

Related Article: F.Hueso-Urena, A.L.Penas-Chamorro, M.N.Moreno-Carretero, J.M.Amigo, V.Esteve, T.Debaerdemaeker|1999|Polyhedron|18|2205|doi:10.1016/S0277-5387(99)00108-4

Aqua-((6-amino-5-formyl-13-dimethyluracil)benzoylhydrazonato)-perchlorato-copper(ii) perchlorateSpace GroupCrystallographyCrystal SystemCrystal StructureCell ParametersExperimental 3D Coordinates
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CCDC 258321: Experimental Crystal Structure Determination

2005

Related Article: M.L.Calatayud, J.Sletten, M.Julve, I.Castro|2005|J.Mol.Struct.|741|121|doi:10.1016/j.molstruc.2005.01.069

Aqua-(123-trioxocyclopent-4-en-45-diolato)-(22':6'2''-terpyridine)-nickel(ii) monohydrateSpace GroupCrystallographyCrystal SystemCrystal StructureCell ParametersExperimental 3D Coordinates
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CCDC 235074: Experimental Crystal Structure Determination

2005

Related Article: J.Pasan, J.Sanchiz, C.Ruiz-Perez, F.Lloret, M.Julve|2004|Eur.J.Inorg.Chem.||4081|doi:10.1002/ejic.200400260

Aqua-(22'-bipyridyl)-(phenylmalonato)-copper(ii) dihydrateSpace GroupCrystallographyCrystal SystemCrystal StructureCell ParametersExperimental 3D Coordinates
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CCDC 200157: Experimental Crystal Structure Determination

2004

Related Article: J.Carranza, C.Brennan, J.Sletten, B.Vangdal, P.Rillema, F.Lloret, M.Julve|2003|New J.Chem.|27|1775|doi:10.1039/b301212n

Aqua-(croconato)-(22'-bipyrazine)-copper(ii)Space GroupCrystallographyCrystal SystemCrystal StructureCell ParametersExperimental 3D Coordinates
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