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ABSTRACT: Two new μ-oxamido-bridged trinuclear complexes, namely [Cu(3)L(2)(H(2)O)(2)]{[Cu(3)L(2)]·2H(2)O}(2) (1) and [Ni(3)L(2)(H(2)O)(DMF)](H(2)O)(DMF) (2), where L(3-) is deprotonated N-(5-chloro-2-hydroxyphenyl)-N'-[3-(dimethylamino)propyl]oxamide, have been synthesized and characterized by X-ray single-crystal diffraction. The structure of complex 1, which consists of three tricopper(II) neutral molecules, lies on an inversion centre at Cu5 atom and thus has a trans conformation. The structure of complex 2 composes of a trinickel(II) neutral molecule. In vitro cytotoxic activities, and the reactivities of the two complexes towards DNA and protein are investigated. Cytotoxicities experiments reveal that the two trinuclear complexes both exhibits cytotoxic effects against human hepatocellular carcinoma cell SMMC-7721 and human lung adenocarcinoma cell A549. The interactions of the two complexes with herring sperm DNA (HS-DNA) are investigated by using UV absorption and fluorescence spectra and viscometry. The results suggested that both of the two trinuclear complexes could interact with HS-DNA through the intercalation mode and follow the binding affinity order of 1>2. The reactivity towards protein BSA revealed that the quenching of BSA fluorescence by the two complexes are static quenching, and complex 1 exhibits a higher BSA-binding ability than that of complex 2.
Journal of photochemistry and photobiology. B, Biology 11/2012; · 1.87 Impact Factor
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ABSTRACT: A new asymmetrical N,N'-bis(substituted)oxamide ligand, N-(5-chloro-2-hydroxyphenyl)-N'-[3-(dimethylamino)propyl]oxamide (C(13)H(18)N(3)O(3)Cl·H(2)O, H(3)L) and its two binuclear complexes [Cu(2)L(H(2)O)(bpy)](ClO(4))·CH(3)OH (1) and [Ni(2)L(bpy)(2)](ClO(4)) (2) [bpy = 2,2'-bipyridine] have been synthesized and characterized by X-ray single-crystal diffraction. In the crystal structure, H(3)L adopting a transoid conformation occurs as a neutral molecule linked with a water molecule by an intermolecular hydrogen bond. In the two complexes, the cis-L(3-) ligand bridges two metal ions with the corresponding separations of 5.2032(15) Å (1) and 5.2466(7) Å (2), respectively. In vitro cytotoxic activities, and the reactivities of the three compounds towards DNA and protein are investigated.
European journal of medicinal chemistry 06/2012; 54:697-708. · 3.27 Impact Factor
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ABSTRACT: Two new circular tetranuclear copper(II) complexes, [Cu(4)(dmoxba)(2)(bpy)(2)(CH(3)OH)(2)](pic)(2)·2H(2)O (1) and [Cu(4)(dmoxba)(2)(phen)(2)](pic)(2)·2CH(3)OH (2), where dmoxba, pic, bpy and phen stand for the anion of 2-{N'-[2-(dimethylamino)ethyl]oxamido}benzoate, picrate, 2,2'-bipyridine and 1,10-phenanthroline, respectively, have been synthesized and structurally characterized by X-ray single-crystal diffraction. Both the complexes have embedded inversion centers and similar complex cations assembled by the oxamide-bridges and carboxylate-bridges of two cis-dmoxba(3-) ligands. The Cu···Cu separations through the oxamide-bridge and the carboxylato-bridge are 5.1991(4) and 5.4674(4) Å in 1 and 5.1843(5) and 5.2138(5) Å in 2, respectively. Both copper(II) ions are in square-pyramidal environments in 1. While in complex 2, the inner and exo copper(II) ions have square-planar and square-pyramidal coordination geometries, respectively. In both the crystals, three-dimensional supramolecular structures are formed by hydrogen bonds and π-π stacking interactions. The DNA-binding properties and anticancer activities of the two complexes were investigated. The results suggest that the two complexes interact with HS-DNA in the mode of intercalation with the intrinsic binding constants 5.0×10(4) M(-1) (1) and 6.7×10(4) M(-1) (2). The influence of structural variation of the terminal ligands in the tetranuclear complexes on DNA-binding properties is preliminarily discussed.
Journal of photochemistry and photobiology. B, Biology 05/2012; 114:27-37. · 1.87 Impact Factor
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ABSTRACT: A new nitrosyl-bridged bimetallic nitroprusside complex, [Ba(phen)3(H2O)][Fe(CN)5NO]·1.5phen·2H2O (phen=1,10-phenanthroline) (1), has been synthesized and characterized by elemental analysis and single crystal X-ray diffraction. The crystal structure
analysis reveals that complex 1 crystallizes in the triclinic space group Pī. The asymmetric structural unit is comprised of one [Ba(phen)3(H2O)]2+ complex cation, one [Fe(CN)5NO]2– complex anion, 1.5-uncoordinated phenanthroline molecules and two lattice water molecules. The complex ions are linked into
a 1D chain-like arrangement by the trans CN and NO groups in nitroprusside. The six-coordinated Fe-atom forms a distorted octahedral coordination configuration, and
the Ba-atom has a nine-coordinate monocapped antiprismatic geometry. Five types of π–π stacking interactions of phenanthroline
and some intra- and intermolecular hydrogen bonds are observed in the 3D supramolecular self-assembly. Absorption spectroscopy,
fluorescence titration and viscometry studies of the interaction between complex 1 and calf thymus DNA indicate that complex 1 is a moderate metallo-intercalator with the intrinsic binding constant of 3.70×104M−1 and the linear Stern–Volmer quenching constant of 5.98×104M−1.
KeywordsNitroprusside complex-Crystal structure-Supramolecular self-assembly-π–π stacking-DNA binding-Spectrum
Journal of Inorganic and Organometallic Polymers and Materials 05/2012; 20(4):657-665. · 1.45 Impact Factor
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ABSTRACT: A new cyano-bridged copper (I) complex {[Cu(phen)CN][Cu(phen)][Cu(CN)2]}
n
(1) (phen=1,10-phenanthroline) was synthesized under the solvothermal conditions, and characterized by elemental analysis,
FI-IR spectra and single-crystal X-ray diffraction. The structure analysis reveals that complex 1 contains two [Cu(phen)CN][Cu(phen)][Cu(CN)2] subunits, being, respectively, constructed into two chains with different cyano backbones. The resulting chains offer a
double curvy chain by Cu···Cu weak interactions and π–π stacking interactions. It is exciting that the double curvy chains
adopt anti-parallel array and result in a novel 3D architecture through π–π stacking interactions. According to the supramolecular
self-assembly of complex 1, four types of stacking mode of phenanthroline moieties are given and discussed. Absorption and fluorescence titration studies
of complex 1 with calf thymus DNA are suggestive of the intercalation binding mode with a intrinsic binding constant of 7.52×103 M−1 and a linear Stern-Volmer quenching constant of 1.02×105 M−1.
Journal of Inorganic and Organometallic Polymers and Materials 04/2012; 18(3):398-406. · 1.45 Impact Factor
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ABSTRACT: A new one-dimensional copper(II) polymer, [Cu4(dmapox)2(SCN)4(CH3OH)2]
n
, where dmapox is the dianion of N,N′-bis[3-(dimethylamino)propyl]oxamide, was synthesized and characterized by elemental analysis, conductivity measurement,
IR, and electronic spectral studies. The crystal structure of the copper(II) complex has been determined by X-ray single-crystal
diffraction. The complex crystallizes in triclinic, space group P−1 and exhibits infinite one-dimensional copper(II) polymeric chain bridged both by bis-tridentate μ-trans-dmapox and μ-1,3-thiocyanato ligand. The environment around the copper(II) atom can be described as distorted square-pyramid.
The Cu···Cu separations through the oxamidate and thiocyanato bridges are 5.246(2)Å (Cu1–Cu1i), 5.2649(14)Å (Cu2–Cu2ii), and 5.8169(15)Å (Cu1–Cu2), respectively. The interaction of the copper(II) complex with herring sperm DNA (HS-DNA) has
been investigated by using absorption and emission spectral and electrochemical techniques and viscometry. The results reveal
that the copper(II) complex may interact with DNA in the mode of groove binding with the intrinsic binding constant of 2.56×105M−1.
Structural Chemistry 04/2012; 19(5):819-826. · 1.85 Impact Factor
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ABSTRACT: A novel 2D sheet-like copper(II) complex formulated [Cu6(trans-oxen)3(μ3-OH)2(H2O)2]n-(ClO4)4n.2nH2O (1), where H2oxen is N,N’-bis(2-aminoethyl)oxamide, has been synthesized and characterized by elemental analysis, IR and UV–visible spectroscopy,
and single-crystal X-ray diffraction. 1 crystallizes in triclinic space group P-1 with crystallographic data: a=10.299(2)Å, b=10.833(2)Å, c=11.781(2)Å, α=69.95(3)°, β=81.10(3)°, γ=62.44(3)°, and Z=2. In the crystal structure, the cation [Cu6(trans-oxen)3(μ3-OH)2(H2O)2]n4n+ exhibits a two-dimensional sheet-like structure for Cu(II) ions bridged both by trans-oxen and hydroxyl groups. Each Cu(II) ion is located in a slightly distorted square-pyramidal environment. The hydroxyl group
bridges three [Cu(oxen)Cu]2+ dications in which one oxen2− is μ2-bridge while the other two act as never before reported μ4-bridge. Perchlorate anions and H2O molecules are inserted between the sheets and bridge the 2D cations via N–H···O and O–H···O hydrogen bonds to form an infinite
three-dimensional system. The cyclic voltammetric behavior of 1 and the influence of counter ions on structure are preliminarily investigated.
Keywordsμ4-Oxamidato-bridge–μ3-Hydroxyl-bridge–Cu(II) coordination polymer–Crystal structure–Cyclic voltammetry
Journal of Inorganic and Organometallic Polymers and Materials 04/2012; 21(1):182-188. · 1.45 Impact Factor
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ABSTRACT: Two tetranuclear copper(II) complexes bridged by asymmetrical N,N′-bis(substituted)oxamides have been synthesized and characterized as [Cu4(dmapob)2(Me2bpy)2](pic)2·6H2O (1) and [Cu4(oxbe)2(dabt)2](pic)2 (2), where H3dmapob and H3oxbe denote N-benzoato-N′-[3-(dimethylamino)propyl]oxamido and N-benzoato-N′-(2-aminoethyl)oxamide, respectively; and Me2bpy, dabt, and pic represent 4,4′-dimethyl-2,2′-bipyridine 2,2′-diamino-4,4′-bithiazole, and 2,4,6-trinitrophenol, respectively.
Complex 1 was characterized by elemental analyses, IR and electronic spectra, and single-crystal X-ray diffraction. Its structure consists
of two asymmetrical binuclear copper(II) units linked by carboxyl bridges into a circular tetranuclear copper(II) complex
with an embedded center of inversion. The copper(II) centers are in square-planar and distorted square-pyramidal environments.
Hydrogen bonds and aromatic stacking interactions link the tetranuclear copper(II) fragments into a 3D supramolecular structure.
The interactions of complexes 1 and 2 with herring sperm DNA (HS-DNA) were investigated by electronic and fluorescence spectra and viscosity measurements. Both
complexes bind to HS-DNA via the intercalative mode, and complex 2 displays a significant binding propensity to HS-DNA.
Transition Metal Chemistry 04/2012; 36(4):341-349. · 1.02 Impact Factor
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ABSTRACT: Two ammonium decavanadate(V) compounds, (H2tmen)3V10O28·6H2O (1) and (H2en)3V10O28·2H2O (2), where H2tmen and H2en represent the doubly protonated N,N,N′,N′-tetramethylethylenediammonium ion and doubly protonated ethylenediammonium ion, respectively, have been synthesized and
structurally characterized by elemental analyses, spectroscopic (i.r., e.s.r.) studies, and single-crystal X-ray diffraction.
Both crystal structures reveal the presence of the [V10O28]6− cluster anions, doubly protonated diammonium cations, and lattice water molecules. Hydrogen bonds assemble these two compounds
to form three-dimensional networks. The in vitro anticancer activity against A549 and P388 tumor cells lines has also been
determined by the MTT-based assay, and the results suggest that both compounds can inhibit proliferation of these two kinds
of tumor cells.
Transition Metal Chemistry 04/2012; 35(5):597-603. · 1.02 Impact Factor
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ABSTRACT: A new one-dimensional polymeric copper(II) complex, [Cu2(heae)(SCN)2]
n
·nH2O [H2heae is N,N′-bis(N-hydroxyethylaminoethyl)oxamide], has been synthesized and characterized by elemental analysis, molar conductivity measurement,
IR and electronic spectra studies, and single-crystal X-ray diffraction. The structure of the complex exhibits a neutral one-dimensional
polymeric copper(II) zigzag chain [Cu2(heae)(SCN)2]
n
constructed by μ-trans-heae and double μ-1,3-thiocyanate ligands. The environment about copper can be described as a square-pyramid. The neighboring second building
units (SBUs), [Cu(trans-heae)Cu]2+, are unequal with Cu···Cu separations of 5.287 and 5.273Å for Cu1···Cu1i and Cu2···Cu2ii, respectively. The double thiocyanate ligands function as μ(1,3)-bridges to link these unequal SBUs thereby forming zigzag chains with a Cu1···Cu2 separation of 5.454Å. The hydrogen
bonds in the crystal structure self-assemble the one-dimensional chains into a three-dimensional supramolecular structure.
The interaction of the polymeric copper(II) complex with herring sperm DNA (HS-DNA) has been investigated by using absorption and emission spectra, electrochemical techniques and viscometry. The results
reveal that the polymeric copper(II) complex interacts with HS-DNA via a groove binding mode with the intrinsic binding constant of 1.38×104M−1. To the best of our knowledge, this is the first example about the structure and DNA-bonding studies of a one-dimensional
polymeric copper(II) complex that is bridged alternately by trans-oxamidate and double-thiocyanate ligands.
Journal of Inorganic and Organometallic Polymers and Materials 04/2012; 18(4):448-456. · 1.45 Impact Factor
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ABSTRACT: A novel cyano-bridged heterotrinuclear FeIII/CoII/FeIII complex, [Co(phen)2][Fe(phen)(CN)4]2·4H2O (1) (phen=1,10-phenanthroline), has been synthesized under solvothermal conditions, and characterized by elemental analysis,
FI-IR spectrum and single-crystal X-ray diffraction. The structure analysis reveals complex 1 is constructed into a 3D supramolecular architecture through abundant intermolecular non-covalent interactions. According
to the supramolecular self-assembly of complex 1, five types of π–π stacking models of phenanthroline ligands, hydrogen bonds formed by four lattice water molecules, and
C–H···N weak interactions involving cyano groups are all observed. Electronic absorption spectroscopy and fluorescence titration
studies of the interaction between complex 1 and calf thymus DNA are suggestive of an intercalative binding mode with an intrinsic binding constant of 7.95×103M−1 and a linear Stern–Volmer quenching constant of 1.033×105M−1.
KeywordsSolvothermal synthesis-Trinuclear complex-Crystal structure-Non-covalent interaction-DNA binding
Journal of Inorganic and Organometallic Polymers and Materials 04/2012; 20(1):168-176. · 1.45 Impact Factor
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ABSTRACT: A novel dissymmetrical N,N'-bis(substituted)oxamide ligand, N-(2-aminopropyl)-N'-(2-oxido- phenyl)oxamide (H(3)apopoxd) (L), and its three bicopper(II) complexes, [Cu(2)(apopoxd)(bpy)]- (ClO(4))·H(2)O (1), [Cu(2)(apopoxd)(dabt)](ClO(4))·2H(2)O (2), and [Cu(2)(apopoxd)(phen)(2)](ClO(4)) (3) (bpy = 2,2'-bipyridine; dabt = 2,2'-diamino-4,4'-bithiazole; phen = 1,10-phenanthroline) have been synthesized and characterized. The crystal structures of the three bicopper(II) complexes have been determined by X-ray single-crystal diffraction. In complexes 1 and 2, the cis-apopoxd(3-) ligands bridge two copper(II) ions in square-planar geometries with the corresponding separations of 5.1868(3) and 5.2016(4) Å, respectively. While in complex 3, the apopoxd(3-) ligand adopting a trans conformation bridges the two copper(II) ions in distorted square-pyramid environments with a Cu · · · Cu distance of 5.2508(7) Å. The anticancer activities and DNA-binding properties of L and the three complexes were investigated.
European journal of medicinal chemistry 05/2011; 46(9):3851-7. · 3.27 Impact Factor
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ABSTRACT: The title complex, [CuNi(C(13)H(16)N(3)O(3))(C(10)H(8)N(2))(2)(H(2)O)]ClO(4), has a cis-oxamide-bridged heterobinuclear cation, with a Cu···Ni separation of 5.3297 (6) Å, counterbalanced by a disordered perchlorate anion. The Cu(II) and Ni(II) cations are located in square-pyramidal and octahedral coordination environments, respectively. The complex molecules are assembled into a three-dimensional supramolecular structure through hydrogen bonds and π-π stacking interactions. The influence of the two types of metal cation on the supramolecular structure is discussed.
Acta crystallographica. Section C, Crystal structure communications 04/2011; 67(Pt 4):m115-8. · 0.78 Impact Factor
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ABSTRACT: The title complex, {[Cu(2)(C(14)H(16)N(3)O(4))(C(6)H(6)N(4)S(2))]NO(3)·0.6H(2)O}(n), is a one-dimensional copper(II) coordination polymer bridged by cis-oxamide and carboxylate groups. The asymmetric unit is composed of a dinuclear copper(II) cation, [Cu(2)(dmapob)(dabt)](+) {dmapob is N-(2-carboxylatophenyl)-N'-[3-(dimethylamino)propyl]oxamidate and dabt is 2,2'-diamino-4,4'-bithiazole}, one nitrate anion and one partially occupied site for a solvent water molecule. The two Cu(II) ions are located in square-planar and square-pyramidal coordination environments, respectively. The separations of the Cu atoms bridged by oxamide and carboxylate groups are 5.2053 (3) and 5.0971 (4) Å, respectively. The complex chains are linked by classical hydrogen bonds to form a layer and then assembled by π-π stacking interactions into a three-dimensional network. The influence of the terminal ligand on the structure of the complex is discussed.
Acta crystallographica. Section C, Crystal structure communications 11/2010; 66(Pt 11):m323-6. · 0.78 Impact Factor
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ABSTRACT: Four new copper (II)-manganese (II) heterobinuclear complexes bridged byN, N'-bis[2-(dimethylamino)ethyl)]oxamido dianion (dmoxæ) and end-capped with 1, 10-phenanthroline (phen), 5-methyl-1, 10-phenanthroline (Mephen), diaminoethane (en) or 1,3-di-aminopropane (pn). respectively, namely, [Cu(dmoxae)MnL2] (CIO4)2 (L=phen, Mephen, en, pn), have been synthesized and characterized by elemental analyses, IR, electronic spectral studies, and molar conductivity measurements. The electronic reflectance spectrum indicates the presence of spin exchange-coupling interaction between bridged copper(II) and manganese (II) ions. The cryomagnetic measurements (4.2-300 K) of [Cu(dmoxae)Mn(phen)2](CIO4)2 (1) and [Cu(dmoxae)Mn(Mephen)2](CIO4)2(2) complexes demonstrated an antiferromagnetic interaction between the adjacent manganese(II) and copper (II) ions through the oxamido-bridge within each molecule. On the basis of spin Hamiltonian, H= - 2JS1. S2. the magnetic analysis was carried out for the two complexes and the spin-coupling constant (J) was evaluated as −35.9 cm−1 for 1 and - 32.6 cm−1 for 2. The influence of methyl substitutions in the amine groups of the bridging ligand on magnetic interactions between the metal ions of this kind of complexes is also discussed.
Chinese Journal of Chemistry 08/2010; 19(5):475 - 480. · 0.75 Impact Factor
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ABSTRACT: The title complex, [Cu(4)(C(12)H(22)N(4)O(4))(C(10)H(8)N(2))(4)](ClO(4))(4), has a novel tetranuclear copper(II) cation with the oxamidate and ethanolate groups of a trans tetraanion of N,N'-bis[3-(hydroxyethylamino)propyl]oxamide (H(4)heap) as bridges. The Cu...Cu separation through the oxamide group is 5.1592 (15) A, while those through the two ethanolate bridges are 3.3845 (13) and 3.3392 (13) A. The two central copper(II) ions are in square-planar N(2)O(2) environments, while the two terminal copper(II) ions have distorted N(4)O square-pyramidal geometries. The heap(4-) ligand, with an iminoalcohol form, has both an oxamide and two ethanolate bridges. Two of the four perchlorate anions are disordered and have long contacts with the square-planar Cu(II) ions. The three-dimensional structure features arene-perchlorate C-H...O hydrogen bonds and pi-pi stacking.
Acta crystallographica. Section C, Crystal structure communications 08/2010; 66(Pt 8):m211-4. · 0.78 Impact Factor
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ABSTRACT: The title complex, [Cu(4)(C(11)H(10)N(3)O(4))(2)(C(6)H(6)N(4)S(2))(2)](C(6)H(2)N(3)O(7))(2), consists of a circular tetracopper(II) cation with an embedded inversion centre and two uncoordinated picrate (2,4,6-trinitrophenolate) anions. The Cu(II) cations at the inner sites of N-(2-aminoethyl)-N'-(2-carboxylatophenyl)oxamidate(3-) (oxbe) have square-planar environments and those at the outer sites are in square-pyramidal geometries. The separations of pairs of Cu(II) cations bridged by cis-oxamide and carboxylate groups are 5.2217 (5) and 5.2871 (5) A, respectively. The tetracopper(II) cations and picrate anions are connected by N-H...O hydrogen bonds into a two-dimensional network parallel to the (010) plane, and these two-dimensional networks are assembled by two types of pi-pi stacking interactions into a three-dimensional supramolecular structure.
Acta crystallographica. Section C, Crystal structure communications 08/2010; 66(Pt 8):m218-21. · 0.78 Impact Factor
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ABSTRACT: A new oxamido-bridged tetracopper(II) complex, [Cu4(oxbe)2(bpy)2](ClO4)2 · 2H2O, where H3oxbe and bpy stand for N-benzoato-N′-(2-aminoethyl)oxamide and 2,2′-bipyridine, has been synthesized and characterized by elemental analyses, molar conductivity, infrared and electronic spectra, and single-crystal X-ray diffraction. It crystallizes in triclinic system, space group P-1, with crystallographic data: a = 7.829(5) Å, b = 12.680(5) Å, c = 13.420(5) Å, α = 104.665(5)°, β = 95.275(5)°, γ = 106.931(5)°, and Z = 1. The circular tetranuclear copper(II) cation [Cu4(oxbe)2(bpy)2]2+ with an embedded center of inversion is assembled by a pair of cis-oxbe-bridged dinuclear copper(II) units through coordination between carboxyl and copper(II). One copper(II) is located in a slightly distorted square-planar environment, while the other is in a distorted square-pyramidal geometry. In the crystal structure, abundant hydrogen bonds and aromatic stackings link the tetranuclear copper(II) units into an overall 3-D framework. Interactions of the tetranuclear copper(II) complex with herring sperm DNA (HS-DNA) are investigated by using UV absorption and fluorescence spectra, electrochemical techniques, and viscometry. The results suggest that the tetranuclear copper(II) complex interacts with DNA by intercalation with an intrinsic binding constant of 1.47 × 105 mol−1 L.
Journal of Coordination Chemistry 05/2010; 63(9):1582-1596. · 1.55 Impact Factor
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ABSTRACT: The title complex, bis[mu(3)-cis-N-(2-aminopropyl)-N'-(2-carboxylatophenyl)oxamidato(3-)]-1:2:4kappa(7)N,N',N'',O:O',O'':O''';2:3:4kappa(7)O''':N,N',N'',O:O',O''-bis(2,2'-bipyridine)-2kappa(2)N,N';4kappa(2)N,N'-dichlorido-1kappaCl,3kappaCl-tetracopper(II) dihydrate, [Cu(4)(C(12)H(12)N(3)O(4))(2)Cl(2)(C(10)H(8)N(2))(2)].2H(2)O, consists of a neutral cyclic tetracopper(II) system having an embedded centre of inversion and two solvent water molecules. The coordination of each Cu(II) atom is square-pyramidal. The separations of Cu(II) atoms bridged by cis-N-(2-aminopropyl)-N'-(2-carboxylatophenyl)oxamidate(3-) and carboxyl groups are 5.2096 (4) and 5.1961 (5) A, respectively. A three-dimensional supramolecular structure involving hydrogen bonding and aromatic stacking is observed.
Acta crystallographica. Section C, Crystal structure communications 04/2009; 65(Pt 3):m115-7. · 0.78 Impact Factor
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ABSTRACT: A new two-dimensional polymeric copper(II) complex, [Cu2(heae)(N3)2] n , where heae stands for the dianion of N,N′-bis(N-hydroxyethylaminoethyl)oxamide, has been synthesized and characterized by elemental analysis, molar conductivity measurement, IR, electronic spectral studies and single-crystal X-ray diffraction. The compound crystallizes in the monoclinic system, P21/c space group with crystallographic data: a = 9.1588(18) Å, b = 6.6238(13) Å, c = 14.602(3) Å and Z = 2. The X-ray analysis reveals a two-dimensional copper(II) polymeric coordination network constructed by bis-tridentate chelated [Cu(trans-heae)Cu]2+ building blocks and end-on azido ligands. The environment around the copper(II) atom can be described as a square-based pyramid. The azido bridge is very asymmetric with one Cu–N bond distance short and the other long. The Cu ··· Cu separations through μ-trans-oxamidate and μ-azido bridges are 5.2996(13) Å and 4.2464(7) Å, respectively. The copper(II) complex is a polymer in the solid state, whereas in solution it exists as discrete neutral binuclear copper(II) species. Coordination mode of the azide in solution is proved by electronic spectra. The DNA-binding properties of the binuclear copper(II) species were investigated by emission spectral and electrochemical techniques, indicating the binuclear copper(II) complex binds to HS-DNA via a groove mode.
Journal of Coordination Chemistry 02/2009; 62(3):380-389. · 1.55 Impact Factor
