Search results for "2'"
showing 10 items of 1745 documents
Synthesis, X‐ray Studies and Magnetic Properties of Dinuclear Ni II and Cu II Complexes Bridged by the Azo‐2,2′‐bipyridine Ligand
2003
Two new paramagnetic transition metal complexes that contain the bridging ligand azo-2,2-bipyridine (abpy) have been prepared and characterized by X-ray crystallography and magnetic susceptibility measurements. The compound [Ni2(µ-abpy)(CH3CN)2(NO3)4]·2CH3CN (1·2CH3CN) crystallizes in the triclinic space group P1 ¯ with a = 8.290(5) A u , b = 8.343(5) A u , c = 11.180(5) A u , α = 105.36(3)°, β = 94.39(3)°, γ = 107.56(3)°, V = 700.5(7) A u 3 and Z = 1. The related salt [Cu2(µ
A two-dimensional magnetic architecture with bridging polynitrile and 2,2′-bipyrimidine ligands
2004
cited By 7; International audience; A new polymeric, two-dimensional compound [Co2(bpym)(dcne) 4 (H2O)2] (1) (dcne = [(CN)2CC(O) OEt)]- = 2,2-dicyano-1-ethoxyethenolate anion and bpym = 2,2'-bipyrimidine) has been synthesized and characterized by X-ray crystallography. The structure is monoclinic space group P21/a and consists of two-dimensional networks of octahedrally coordinated Co(II) ions, bridged by bis-bidentate 2,2'-bipyrimidine and μ2-dcne anions. Magnetic measurements revealed a broad maximum in the xm vs T plot at 20 K which is characteristic of antiferromagnetic exchange between the high spin cobalt(II) centres. © EDP Sciences.
Synthesis and characterization of triphenyltin(IV) 5-[(E)-2-(aryl)-1-diazenyl]-2-hydroxybenzoates. Crystal and molecular structures of Ph3Sn{O2CC6H3-…
2005
Abstract Triphenyltin 5-[(E)-2-(4-methylphenyl)-1-diazenyl]-2-hydroxybenzoate, Ph3SnL2H, has been prepared and characterized, its structure determined by X-ray crystallography, and the structure compared with those of its homologues. Two polymorphs were isolated from the same crystallization attempt. The reactivity of tetrahedral Ph3SnL1H (L1H = 5-[(E)-2-(2-methylphenyl)-1-diazenyl]-2-hydroxybenzoate) towards 2,2′-bipyridine (bipy) has been investigated to ascertain the ability of bipy to coordinate to the Sn-complex and the resultant changes in the molecular architecture. The crystal structure of the product revealed that the bipy moiety does not coordinate to the Sn atom, but forms a cycl…
Structural analysis and magnetic properties of the copper(II) dicyanamide complexes [Cu2(dmphen)2(dca)4], [Cu(dmphen)(dca)(NO3)] and [Cu(4,4′-dmbpy)(…
2004
Abstract The preparation, crystal structures and magnetic properties of three copper(II) compounds of formulae [Cu2(dmphen)2(dca)4] (1), [Cu(dmphen)(dca)(NO3)]n (2) and [Cu(4,4′-dmbpy)(H2O)(dca)2] (3) (dmphen=2,9-dimethyl-1,10-phenanthroline, dca=dicyanamide and 4,4′-dmbpy=4,4′-dimethyl-2,2′-bipyridine) are reported. The structure of 1 consists of discrete copper(II) dinuclear units with double end-to-end dca bridges whereas that of 2 is made up of neutral uniform copper(II) chains with a single symmetrical end-to-end dca bridge. Each copper atom in 1 and 2 is in a distorted square pyramidal environment: two (1) or one (2) nitrile-nitrogen atoms from bridging dca groups, one of the nitrogen…
Geometric isomeric pairs: synthesis, structure, thermal decomposition and magnetic properties of cis- and trans-[Cr(mal)(bpy)(H2O)2][NO3]·xH2O (H2mal…
2001
Abstract Procedures are given for the preparation and isolation of cis-[Cr(mal)(bpy)(H2O)2][NO3]·3H2O (I) and trans-[Cr(mal)(bpy)(H2O)2][NO3]·H2O (II) (H2mal=malonic acid, bpy=2,2′-bipyridine). The single crystals X-ray structure of cis-compound reveals that the cations and anions as well as cations between cations are linked into hydrogen-bonded chains. Unfortunately, little structural information is available for the trans compound II (only isotropic cation refinement), nevertheless, from this result is observed that there also exists a hydrogen-bonded network between anion units. Thermal analysis and magnetic behaviour for both compounds were studied.
(Strept)avidin as host for biotinylated coordination complexes: stability, chiral discrimination, and cooperativity
2005
Incorporation of a biotinylated ruthenium tris(bipyridine) [Ru(bpy)₂(Biot-bpy)]²⁺ (1) in either avidin or streptavidin-(strept)avidin-can be conveniently followed by circular dichroism spectroscopy. To determine the stepwise association constants, cooperativity, and chiral discrimination properties, diastereopure (Λ and δ)-1 species were synthesized and incorporated in tetrameric (strept)avidin to afford (δ-[Ru(bpy)₂(Biot-bpy)]²⁺)x⊂avidin, (Λ- [Ru(bpy)₂(Biot-bpy)]²⁺)x⊂avidin, (δ-[Ru(bpy)₂(Biot- bpy)]²⁺)x⊂streptavidin, and (Λ-[Ru(bpy)₂(Biot-bpy)]²⁺) x⊂streptavidin (x = 1-4) For these four systems, the overall stability constants are log β₄ = 28.6, 30.3, 36.2, and 36.4, respectively. Critical…
Superparamagnetic γ-Fe2O3 nanoparticles with tailored functionality for protein separation
2007
Polymer coated superparamagnetic gamma-Fe(2)O(3) nanoparticles were derivatized with a synthetic double-stranded RNA [poly(IC)], a known allosteric activator of the latent (2-5)A synthetase, to separate a single 35 kDa protein from a crude extract which cross reacted with antibodies raised against the sponge enzyme.
CCDC 696703: Experimental Crystal Structure Determination
2009
Related Article: D.Visinescu, L.M.Toma, O.Fabelo, C.Ruiz-Perez, F.Lloret, M.Julve|2009|Polyhedron|28|851|doi:10.1016/j.poly.2008.12.032
CCDC 919043: Experimental Crystal Structure Determination
2013
Related Article: María Castellano, Wdeson P. Barros, Alvaro Acosta, Miguel Julve, Francesc Lloret, Yanling Li, Yves Journaux, Giovanni De Munno, Donatella Armentano, Rafael Ruiz-García, Joan Cano|2014|Chem.-Eur.J.|20|13965|doi:10.1002/chem.201403987
Modulation of 2′-5′oligoadenylate synthetase by environmental stress in the marine spongeGeodia cydonium
1997
Recently we established the presence of relatively high amounts of 2′-5′oligoadenylates (2′-5′A) and 2′-5′oligoadenylate synthetase (2′-5′A synthetase) in the marine sponge Geodia cydonium. Here we determined by applying radioimmunoassay and high-performance liquid chromatographical methods that the concentration of 2′-5′A and the activity of 2′-5′A synthetase change following exposure of G. cydonium tissue to environmental stress. The 2′-5′A content and the activity of 2′-5′A synthetase, present in crude sponge extract, increase by up to three-fold after treating sponge cubes for 2 h with natural stressors including heat shock (26°C), cold shock (6°C), pH shock (pH 6), and hypertonic shock…