scholarly journals Crystal structures of dibromido{N-[(pyridin-2-yl-κN)methylidene]picolinohydrazide-κ2N′,O}cadmium methanol monosolvate and diiodido{N-[(pyridin-2-yl-κN)methylidene]picolinohydrazide-κ2N′,O}cadmium

Author(s):  
Ali Akbar Khandar ◽  
Farhad Akbari Afkhami ◽  
Harald Krautscheid ◽  
Kenneth Aase Kristoffersen ◽  
Zeliha Atioğlu ◽  
...  

The title compounds, [CdBr2(C12H10N4O)]·CH3OH, (I), and [CdI2(C12H10N4O)], (II), are cadmium bromide and cadmium iodide complexes of the ligand (E)-N′-(pyridin-2-ylmethylene)picolinohydrazide. Complex (I) crystallizes as the methanol monosolvate. In both compounds, the Cd2+cation is ligated by one O atom and two N atoms of the tridentate ligand, and by two bromide anions forming a Br2N2O pentacoordination sphere for (I), and by two iodide anions forming an I2N2O pentacoordination sphere for (II), both with a distorted square-pyramidal geometry. In the crystal of complex (I), molecules are linked by pairs of N—H...O and O—H...Br hydrogen bonds, involving the solvent molecule, forming dimeric units, which are linked by C—H...Br hydrogen bonds forming layers parallel to (101). In the crystal of complex (II), molecules are linked by N—H...I hydrogen bonds, forming chains propagating along [010]. In complex (II), measured at room temperature, the two iodide anions are each disordered over two sites; the refined occupancy ratio is 0.75 (2):0.25 (2).

2021 ◽  
Vol 33 (2) ◽  
pp. 359-366
Author(s):  
Habibar Chowdhury ◽  
Chandan Adhikary

Two copper(II) azido complexes of the types mononuclear [Cu(TMEDA)2(N3)2] (1) and dinuclear [Cu(TMEDA)(μ1,1-N3)(N3)]2 (2) [TMEDA = trimethylenediamine; N3 – = azide ion] have been synthesized and characterized. X-ray structural analysis revealed that each copper(II) center in complex 1 adopts a distorted octahedron geometry with a CuN6 chromophore ligated through four N atoms of two different symmetrical TMEDA ligands as bidentate chelator and two N atoms of two terminal azides. In complex 2, each copper(II) center adopts a distorted square pyramidal geometry with a CuN5 chromophore ligated through two N atoms of TMEDA as bidentate chelator and two N atoms of two different azides as μ1,1-N3 bridging mode and one N atom of terminal azide ion. The two copper centers are connected through double μ1,1-N3 bridges affording a dinuclear structure with Cu···Cu separation 3.327(2) Å. In crystalline state, mononuclear units in complex 1 are associated through intermolecular N-H···N and C-H···N hydrogen bonds to form a 2D sheet structure viewed along crystallographic b-axis, whereas dinuclear entities in complex 2 are propagated through intermolecular N-H···N and C-H···N hydrogen bonds to form a 3D network structure viewed along crystallographic a-axis. The Variable-temperature magnetic susceptibility measurement evidenced a dominant antiferromagnetic interaction between the metal centers through μ1,1-azide bridges in complex 2 with J = − 0.40 cm-1. The antibacterial activities of the complexes have also been studied.


2020 ◽  
Vol 42 (6) ◽  
pp. 928-928
Author(s):  
Fouzia Chang Fouzia Chang ◽  
Najma Memon Najma Memon ◽  
Shahabuddin Memon Shahabuddin Memon ◽  
Muhammad Naeem Ahmed Muhammad Naeem Ahmed ◽  
Muhammad Nawaz Tahir Muhammad Nawaz Tahir ◽  
...  

A novel Poly [bis-and#181;-3,5-dinitro-2-oxidobenzoato) (py) Cu II]/(C12H7CuN3O7) was synthesized by a self assemble method at room temperature. The molecular structure was determined by single-crystal X-ray analysis. The compound crystallizes in the monoclinic system, space group P 2 1/c with lattice parameters of a = 10.2143, b = 5.1651 and c = 26.608, α = 90, β = 99.720, γ = 90, Z = 4, V = 1383.60 (18) and#197;3.Pore size depicted from single crystal XRD data was 47and#197;. The central metal atom Cu (II) is coordinated with oxygen of carboxylates group and nitrogen atom of pyridine. The coordination polyhedron posses square pyramidal geometry is manifested by the N— Cu—O angle of 90o. The structure is composed of monomeric coordination units with the central copper (II) ion is not occupying a centre of symmetry.


Circulation ◽  
2019 ◽  
Vol 140 (Suppl_2) ◽  
Author(s):  
Johannes A Pille ◽  
Michele M Salzman ◽  
Anna A Sonju ◽  
Felicia P Lotze ◽  
Josephine E Hees ◽  
...  

Introduction: In a pig model of myocardial infarction (MI), intracoronary delivered Poloxamer (P) 188 significantly reduces ischemia/reperfusion (IR) injury when given immediately upon reperfusion, with improved mitochondrial function as a predominant effect. As mitochondria are heavily damaged during IR, a direct effect of P188 on mitochondria may lead to better therapy options during reperfusion. To show not only a similar reduction of IR injury by P188 in the brain, but also a direct P188 effect on mitochondria, we established an in-vitro model of IR that consists of damaging isolated rat brain mitochondria with hydrogen peroxide (H 2 O 2 ), one component of ischemia, then applying P188, and analyzing mitochondrial function. Methods: Male Sprague-Dawley rat brains were removed, and the mitochondria isolated by differential centrifugation and Percoll gradients, then kept on ice to slow their bioenergetics prior to any experimental treatments. Mitochondria were exposed to 200 μM H 2 O 2 for 10 min at room temperature with slight agitation; controls received no H 2 O 2 . Samples were then diluted ½ with buffer ± P188 (250 μM after dilution) to simulate reperfusion and treatment, and kept at room temperature for 10 further minutes. ATP synthesis was measured in a luminometer using a luciferase enzymatic assay. Oxygen consumption was measured by closed cell respirometry with an oxygen meter. In both assays, Complex I and Complex II were examined; Complex I substrates glutamate and malate, Complex II substrate succinate plus the Complex I inhibitor rotenone. Statistics: Data are expressed as mean ± SEM. One-Way ANOVA, SNK-Test; Kruskal-Wallis-Test; α=0.05, * vs control. Results: In both Complex I and II, mitochondrial function was significantly impaired by H 2 O 2 , with ATP synthesis affected more at Complex I and oxygen consumption affected more at Complex II. Addition of P188 did not provide any significant improvement in mitochondrial function. Conclusions: Although P188 significantly reduced IR injury when given during reperfusion in a pig model of MI, it does not appear to provide direct protection to mitochondria in this in-vitro model. Whether the exposure to H 2 O 2 causes the appropriate injury for P188 to become effective remains to be elucidated.


Author(s):  
Wafa Harhouri ◽  
Salma Dhifaoui ◽  
Shabir Najmudin ◽  
Cecilia Bonifácio ◽  
Habib Nasri

In the title compound, [Mn(C44H28N4)Cl]·2C5H6N2, the MnIIIcentre is coordinated by four pyrrole N atoms [averaged Mn—N = 2.012 (4) Å] of the tetraphenylporphyrin molecule and one chloride axial ligand [Mn—Cl = 2.4315 (7) Å] in a square-pyramidal geometry. The porphyrin macrocycle exhibits a non-planar conformation with majorrufflingandsaddlingdistortions. In the crystal, two independent solvent molecules form dimers through N—H...N hydrogen bonding. In these dimers, one amino N atom has a short Mn...N contact of 2.642 (1) Å thus completing the Mn environment in the form of a distorted octahedron, and another amino atom generates weak N—H...Cl hydrogen bonds, which link further all molecules into chains along theaaxis.


2014 ◽  
Vol 70 (4) ◽  
pp. 359-363 ◽  
Author(s):  
Zouaoui Setifi ◽  
Fatima Setifi ◽  
Mohamed Saadi ◽  
Djamil-Azzeddine Rouag ◽  
Christopher Glidewell

In the title compound, [Cu(C2N3)2(C12H10N6)]nor [Cu(dca)2(abpt)]n, where abpt is 4-amino-3,5-bis(pyridin-2-yl)-4H-1,2,4-triazole and dca is the dicyanamide anion, the CuIIcentre is five-coordinate with an approximately square-pyramidal geometry. One of the two dicyanamide ligands is a terminal ligand, but the other one acts as a μ1,5-bridging ligand between pairs of CuIIcentres, so generating a one-dimensional coordination polymer. A combination of N—H...N and C—H...N hydrogen bonds, augmented by π–π stacking interactions, links the coordination polymer chains into a bilayer structure. Comparisons are made with some related CuIIcomplexes containing dca ligands and heteroaromatic co-ligands.


2014 ◽  
Vol 70 (7) ◽  
pp. 718-721
Author(s):  
Zhengliang Lu ◽  
Yuanchao Zhao ◽  
Baolian Chen ◽  
Ximing Huang ◽  
Chunhua Fan

The title compound, [MnCl2(C24H20N6)], has been synthesized and characterized based on the multifunctional ligand 2,5-bis(2,2′-bipyridyl-6-yl)-3,4-diazahexa-2,4-diene (L). The MnIIcentre is five-coordinate with an approximately square-pyramidal geometry. TheLligand acts as a tridendate chelating ligand. The mononuclear molecules are bridged into a one-dimensional chain by two C—H...Cl hydrogen bonds. These chains are assembled into a two-dimensional layer through π–π stacking interactions between adjacent uncoordinated bipyridyl groups. Furthermore, a three-dimensional supramolecular framework is attained through π–π stacking interactions between adjacent coordinated bipyridyl groups.


2012 ◽  
Vol 68 (4) ◽  
pp. m468-m468 ◽  
Author(s):  
Yan Qi ◽  
Yang Li ◽  
Zheng-Ping Ma ◽  
Qiu-Yun Chen

The title compound, [Cu(NCS)2(C20H21N3)]·0.5CH2Cl2, crystallized with two independent complex molecules (AandB) in the asymmetric unit, accompanied by one dichloromethane solvent molecule. Each CuIIatom has a square-pyramidal geometry, being coordinated by five N atoms, three from the (4-methylbenzyl)bis(pyridin-2-ylmethyl)amine ligand and two from the thiocyanate ligands. In the crystal, theBmolecules are linkedviaC—H...S interactions, forming chains propagating along [100].


2001 ◽  
Vol 56 (6) ◽  
pp. 521-525 ◽  
Author(s):  
Maciej Bujak ◽  
Jacek Zaleski

AbstractN ,N-Dimethylethylenediammonium pentachloroantimonate(III) crystallizes in the monoclinic system, in space group P21/c (a = 12.460(2), b = 10.252(2), c = 10.330(2) Å, β = 97.75(3)°, V = 1307.5(4) Å3, Z = 4, dc = 1.997, dm = 1.99(2) g/cm3). The crystal structure of [(CH3)2NH(CH2)2NH3][SbCl5] consists of isolated [SbCl5]2- anions and [(CH3)2NH(CH2)2NH3]2+ cations. The [SbCl5]2- anion has a distorted square pyramidal geometry, presenting one short axial and four long equatorial Sb-Cl bonds. The square pyramids are characteristically stacked one close to the other, parallel to the c axis. The voids between the anionic sublattice are filled by [(CH3)2NH(CH2)2NH3]2+ cations. The five non-equivalent Sb-Cl bond distances within the [SbCl5]2- square pyramid are significantly different. The equatorial Sb-Cl bonds are in the range 2.427(2)-2.968(2) Å, whereas the axial one is 2.384(1) Å long. The study reveals that N-H...C1 hydrogen bonds are responsible for the deformation of equatorial Sb-Cl bonds from the mean value of 2.654(7) Å. Analysis of intermolecular interactions between the [SbCl5]2- pyramids in the structure, reflected in changes of Sb-Cl bond lengths from the values characteristic of non-interacting pyramids, leads to the conclusion that the van der Waals radius of Sb is significantly smaller than that estimated by Pauling.


Author(s):  
Dilovan S. Cati ◽  
Helen Stoeckli-Evans

The title pyrazine dicarboxamide ligand, N 2,N 3-bis(quinolin-8-yl)pyrazine-2,3-dicarboxamide (H2L1), C24H16N6O2, has a twisted conformation with the outer quinoline groups being inclined to the central pyrazine ring by 9.00 (6) and 78.67 (5)°, and by 79.94 (4)° to each other. In the crystal, molecules are linked by C—H...O hydrogen bonds, forming layers parallel to the (10\overline{1}) plane, which are in turn linked by offset π–π interactions [intercentroid distances 3.4779 (9) and 3.6526 (8) Å], forming a supramolecular three-dimensional structure. Reaction of the ligand H2L1 with Cu(ClO4)2 in acetonitrile leads to the formation of the binuclear complex, [μ-(3-{hydroxy[(quinolin-8-yl)imino]methyl}pyrazin-2-yl)[(quinolin-8-yl)imino]methanolato]bis[diacetonitrilecopper(II)] tris(perchlorate) acetonitrile disolvate, [Cu2(C24H15N6O2)(CH3CN)4](ClO4)3·2CH3CN or [Cu2(HL1−)(CH3CN)4](ClO4)3·2CH3CN (I). In the cation of complex I, the ligand coordinates to the copper(II) atoms in a bis-tridentate fashion. A resonance-assisted O—H...O hydrogen bond is present in the ligand; the position of this H atom was located in a difference-Fourier map. Both copper(II) atoms are fivefold coordinate, being ligated by three N atoms of the ligand and by the N atoms of two acetonitrile molecules. The first copper atom has a perfect square-pyramidal geometry while the second copper atom has a distorted shape. In the crystal, the cation and perchlorate anions are linked by a number of C—H...O hydrogen bonds, forming a supramolecular three-dimensional structure.


IUCrData ◽  
2018 ◽  
Vol 3 (8) ◽  
Author(s):  
Mercedes S. Naugle ◽  
Brittany T. Keller ◽  
Matthias Zeller ◽  
Curtis M. Zaleski

The title compound, [Cu2Cl4(C15H12N2)2(C3H7NO)2], Cu2(μ-Cl)2Cl2(3,5-diphenyl-1H-pyrazole)2(DMF)2, where DMF isN,N-dimethylformamide, crystallizes in the monoclinic space groupP21/n. The five-coordinate CuIIions have a distorted square-pyramidal geometry and are joinedviatwo μ-Cl anions. The coordination environment of each CuIIion is completed by a terminal chloride anion, a nitrogen-coordinated 3,5-diphenyl-1H-pyrazole molecule, and a DMF molecule. Two intramolecular hydrogen bonds exist in the molecule as the H atom of the protonated N atom of the 3,5-diphenyl-1H-pyrazole bonds to a terminal chloride anion of the adjacent CuIIcation. In addition, molecules are linked into a two-dimensional sheetviaweak C—H...Cl intermolecular hydrogen bonds. Each dimer hydrogen bonds to four neighboring molecules as the H atom of the C atom in the fourth position of the pyrazole ring bonds to a μ-Cl on a neighboring molecule.


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