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1.
A new Schiff base copper(II) complex, Cu(o-VANAHE)(2) (o-VANAHE = 2-(o-vanillinamino)-1-hydroxyethane), has been synthesized and characterized. Single crystal X-ray diffraction results suggest that this complex structure belongs to triclinic crystal system, space group P1 with the following crystallographic parameters: a = 8.819(4) angstroms, b = 10.794(5) angstroms, c = 11.350(5) angstroms, alpha = 70.262(6) degrees, beta = 70.816(6) degrees, gamma = 78.360(6) degrees, V = 955.4(7) angstroms3, Z = 2, D(c) = 1.571 Mg x m(-3), and the final R1 = 0.0393, wR2 = 0.0994 for the observed reflections 2620(I > 2sigma(I)). The molecular geometry is almost coplanar. Viscosity, fluorescence spectroscopy and cyclic voltammetry have been conducted to assess their interaction between this complex and DNA. Results showed that the copper(II) complex can increase DNA's relative viscosity and quench the fluorescence intensity of EB bound to DNA. The adding of DNA to the solution of Cu(o-VANAHE)2 causes a slight decrease in the voltammetric current, as well as a slight shift in the E(1/2) to less negative potential. The interaction between the complex and DNA has also been investigated by submarine gel electrophoresis, interestingly, we found that the copper(II) complex can cleave circular plasmid pBR322 DNA to nicked and linear forms.  相似文献   

2.
The synthesis and characterisation of the following compounds derived from the biological relevant compound ethyl 5-methyl-4-imidazolecarboxylate (emizco) (1): [Cu(emizco)Cl2] (2), [Cu(emizco)2Cl2] (3), [Cu(emizco)2Br2] (4), [Cu(emizco)2(H2O)2](NO3)2 (5) and [Cu(emizco)4](NO3)2 (6), is presented. These compounds were characterised by IR and UV spectroscopic techniques, in addition the crystal structures of compounds 1-5 were determined. For complexes 2-5, emizco is coordinated as a bidentate ligand, through the oxygen atom of the carboxylate moiety and the nitrogen atom of the imidazolic ring. Different geometries are stabilised: compound 2 includes a pentacoordinated square pyramidal metal centre, while 3-5 are derived from octahedral geometry. Halide compounds 3 and 4 show a cis-octahedral arrangement, which is not very common on [CuN2O2X2] systems, while 5 stabilises the trans-octahedral isomer. Compound 6 displays a square planar geometry. Finally, hydrolysis of emizco to its corresponding carboxylic acid (mizco), allowed the preparation of another square planar complex 7, identified as [Cu(mizco)2] 0.5H2O. Solution studies of these compounds indicate that emizco is not substituted from the coordination sphere, remaining as a bidentate ligand. Halides are substituted by water molecules, changing from cis octahedral to the trans-[Cu(emizco)2(H2O)2]2+ isomer.  相似文献   

3.
Two novel mononuclear Cu(II) coordination compounds of the type [Cu(dptaS)Cl(2)] and [Cu(dptaS)Br(2)] (dptaS=1,3-propanediamine, N(1)-[3-aminopropyl]-N(3)-[2-thienylmethylidene] or Schiff mono-base of dipropylenetriamine with 2-thiophene-carboxaldehyde) were prepared by the hydrolysis of the di-bases, [Cu(dptaSS)Cl(2)] and [Cu(dptaSS)Br(2)] (dptaSS=1,3-propanediamine, N(1)-[2-thienylmethylidene]-N(3)-[[2-thienylmethylidene]aminopropyl] or Schiff di-base of dipropylenetriamine with 2-thiophenecarboxaldehyde) to mono-bases with the release of one aldehyde molecule and freeing of the -NH(2) group of the coordinated dpta ligand. The X-ray determined structure of the compound [Cu(dptaS)Cl(2)] was confirmed by spectroscopic methods, magnetic and molar conductivity measurements. The Cu(II) atom is a five-coordinated CuN(3)Cl(2) chromophore with three nitrogen atoms coming up from the (dptaS) ligand and two chlorine atoms completing the square pyramidal geometry. Antiproliferative activity of both novel compounds was examined against a panel of different normal and cancer cell lines (MRC5, HeLa, MCF7, HT-29 and T47D) and showed that the Cu(II) Schiff mono-bases exhibit increased activity as compared to the starting materials. In vitro studies of plasmid DNA (pDNA) and double stranded DNA (dsDNA) interaction with the compounds under study support this difference. Some of the important factors contributing to the antiproliferative activity of the compounds under study, such as ionic character and dipole moment were also discussed in terms of the density functional theory calculated electronic structures of the ligands and their Cu(II) compounds.  相似文献   

4.
A new series of complexes of the type [Cu(dien)(2a-2tzn)Y(2)] and [Cu(dienXX)(2a-2tzn)Y(2)], where dien=diethylenetriamine and dienXX=Schiff dibase of diethylenetriamine formed with 2-furaldehyde (dienOO), 2-thiophenecarboxaldehyde (dienSS), or pyrrol-2-carboxaldehyde (dienNN); Y=Cl, Br or NO(3); and 2a-2tzn=2-amino-2-thiazoline, were synthesized and their structure established by C, H, N and Cu analysis; IR and electronic spectra; magnetic susceptibility; and molar conductivity. The isolated complexes are monomers, paramagnetic, and electrolytes of types 1:1 or 1:2. In both types of solid state complexes, [Cu(dien)(2a-2tzn)Y(2)] and [Cu(dienXX)(2a-2tzn)Y(2)], dien and its Schiff dibases are bonded to Cu(II) in a tridentate fashion through 3N atoms. The coordination sphere is completed by the endocyclic nitrogen of the thiazoline moiety and by two Cl, Br, or NO(3) groups with distorted octahedral geometry. The proposed structure of these compounds was supported by X-ray analysis of [Cu(dien)(Br)(2a-2tzn)](Br)(H(2)O). The coordination polyhedron around the copper atom can be described as a distorted square pyramid [Cu(dien)(Br)(2a-2tzn)](+). Its basal plane is occupied by the four nitrogen atoms of the dien and thiazoline ligands with Cu-N distances ranging between 1.996(6) and 2.032(3)A, and the axial position is occupied by one of the two bromine atoms (Br1) with a Cu1-Br1 bond distance of 2.782(1)A. The second bromine atom (Br2) is 4.694(2)A from the copper atom, which exists as a discrete anion and is responsible for the cationic nature of the complex. Results regarding toxicity, antitumor, and anti-inflammatory activities of the investigated compounds are promising and allow the selection of a lead compound for further biological studies.  相似文献   

5.
Complexes of the type [M(apash)Cl] and [M(Hapash)(H2O)SO4], where M = Mn(II), Co(II), Ni(II), Cu(II) and Zn(II); Hapash = acetone p-amino acetophenone salicyloyl hydrazone have been synthesized and characterized by elemental analyses, molar conductance, magnetic moments, electronic, ESR and IR spectra, thermal studies (TGA & DTA) and X-ray diffraction studies. The ligand coordinates through two >C=N and a deprotonated enolate group in all the chloro complexes, whereas through two >C=N- and a >C=O group in all the sulfato complexes. The electronic spectra suggest a square planar geometry for Co(II), Ni(II) and Cu(II) chloride complexes and an octahedral geometry for the sulfate complexes. ESR data show an isotropic symmetry for [Cu(apash)Cl] and [Cu(Hapash)(H2O)SO4] in solid state. However, ESR spectra of both Cu(II) complexes indicate the presence of unpaired electron in d x2-y2. The X-ray diffraction parameters for [Co(apash)Cl] and [Cu(Hapash)(H2O)SO4] complexes correspond to a tetragonal and an orthorhombic crystal lattices, respectively. Thermal studies of [Co(apash)Cl] complex shows a multi-step decomposition pattern. Most of the complexes show better antifungal activity than the standard miconazole against a number of pathogenic fungi. The antibacterial activity of these complexes has been evaluated against E. coli and Clostridium sp. which shows a moderate activity.  相似文献   

6.
Based on the importance of the design and synthesis of transition metal complexes with noncovalent DNA/protein‐binding abilities in the field of metallo pharmaceuticals, a new mononuclear ternary copper(II) complex with mixed ligands of diethylenetriamine (dien) and picrate anion (pic), identified as [Cu(dien)(pic)](pic), was synthesized and characterized by elemental analysis, molar conductivity measurement, infrared spectrum, electronic spectral studies, and single‐crystal X‐ray diffractometry. The structure analysis reveals that the copper(II) complex crystallizes in the monoclinic space group P21/c, and the copper(II) ion has a distorted square pyramidal coordination geometry. A two‐dimensional supramolecular structure is formed through hydrogen bonds. The DNA/bovine serum albumin (BSA)‐binding properties of the complex are explored, indicating that the complex can interact with herring sperm DNA via intercalation mode and bind to BSA responsible for quenching of tryptophan fluorescence by static quenching mechanism. The in vitro anticancer activity shows that the copper(II) complex is active against the selected tumor cell lines.  相似文献   

7.
A new series of coordination compounds of the starting materials [Cu(dienX(2)Y(2))] and their adducts [Cu(dienXXY(2))(2a-5mt)] (where dien=diethylenetriamine, dienXX=Schiff bases of diethylenetriamine with 2-furaldehyde or 2-thiophene-carboxaldehyde, X=O, S, Y=Cl, Br, NO(3) and 2a-5mt=2-amino-5-methylthiazole) were synthesized by stepwise reactions and their structures were established by C, H, N, Cu analysis, spectroscopic, magnetic and molar conductivity measurements. The isolated compounds are monomers, paramagnetic and electrolytic compounds of the type 1:1. In all cases, the pentadentate Schiff base (dienXX) is bonded in a tridentate fashion through the 3 N atoms. In the CudienXXY(2) compounds the coordination sphere is completed by two Cl or Br or NO(3) groups in a square pyramidal arrangement. The proposed structure for this type of compound was further supported by X-ray diffraction analysis of the compound [Cu(dienOO)Cl(2)]. Its basal plane consists of three Cu-N contacts [2.017(2), 2.025(2) and 2.012(2) A] from dienOO, and the Cl(1) atom, while the Cl(2) atom possesses the apical position, the relevant distances being 2.2732(7) A for Cu-Cl(1) and 2.6051(7) A Cu-Cl(2). In the CudienX(2)Y(2).2a-5mt adducts the coordination sphere of copper is further completed by the nitrogen ring atom of the 2a-5mt, forming an octahedral configuration. The study of the biological activity of the compounds synthesized against a panel of different normal and cancer cell lines (MRC5, HeLa, MCF7, HT-29, OAW42, T47D) and bacteria (E. coli, B. cereus, B. subtilis) showed that the adducts of the type [Cu(dienXXY(2))(2a-5mt)] exhibit increased activity both in cancer cells and in bacteria, compared to the starting material of type [Cu(dienXXY(2))].  相似文献   

8.
Two asymmetric tridentate copper(II) complexes, [Cu(dppt)Cl(2)].0.25H(2)O (1) (dppt=3-(1,10-phenanthrolin-2-yl)-5,6-diphenyl-as-triazine) and [Cu(pta)Cl(2)] (2) (pta=3-(1,10-phenanthrolin-2-yl)-as-triazino[5,6-f]acenaphthylene), have been prepared and characterized by elemental analysis, IR and Fast atomic bombardment mass spectra. Complex 1 has also been structurally characterized. The complexes exist as distorted square pyramid with five co-ordination sites occupied by the tridentate ligand and the two chlorine anions. DNA interaction studies suggest that the ligand planarity of the complex has a significant effect on DNA binding affinity increasing in the order [Cu(dppt)Cl(2)]< [Cu(pta)Cl(2)]. In the presence of ascorbate or glutathione, the two complexes are found to cause significant cleavage of double-strand pBR 322 DNA and [Cu(pta)Cl(2)] exhibited the higher cleaving efficiency.  相似文献   

9.
J M Veal  K Merchant    R L Rill 《Nucleic acids research》1991,19(12):3383-3388
Copper in the presence of excess 1,10-phenanthroline, a reducing agent, and molecular oxygen causes cleavage of DNA with a preference for T-3',5'-A-steps, particularly in TAT triplets. The active molecular species is commonly thought to be the bis-(1,10-phenanthroline)Cu(I) complex, (Phen)2Cu(I), regardless of the reducing agent type. We have found that (Phen)2Cu(I) is not the predominant copper complex when 3-mercaptopropionic acid (MPA) or 2-mercaptoethanol are used as the reducing agents, but (Phen)2Cu(I) predominates when ascorbate is used as the reducing agent. Substitution of ascorbate for thiol significantly enhances the rate of DNA cleavage by 1,10-phenanthroline + copper, without altering the sequence selectivity. We show that (Phen)2Cu(I) is the complex responsible for DNA cleavage, regardless of reducing agent, and that 1,10-phenanthroline and MPA compete for copper coordination sites. DNA cleavage in the presence of ascorbate also occurs under conditions where the mono-(1,10-phenanthroline)Cu(I) complex predominates (1:1 phenanthroline:copper ratio), but preferential cleavage was observed at a CCGG sequence and not at TAT sequences. The second phenanthroline ring of the (Phen)2Cu(I) complex appears essential for determining the T-3',5'-A sequence preferences of phenanthroline + copper when phenanthroline is in excess.  相似文献   

10.
A new dinuclear copper(II) complex has been synthesised and structurally characterised: [Cu2(tz-ben)4] (Htz-ben = N-thiazol-2-yl-benzenesulfonamide). Its crystal structure, magnetic properties and electronic paramagnetic resonance (EPR) spectra were studied in detail. In the compound the metal centres are bridged by four non-linear triatomic NCN groups. The coordination geometry of the copper ions in the dinuclear entity is distorted square pyramidal (4+1). Two thiazole N and two sulfonamido N atoms occupy the equatorial positions and one sulfonamido O atom is in the axial position. Magnetic susceptibility data show a strong antiferromagnetic coupling, -2J = 114.1 cm(-1). The EPR spectra of a polycrystalline sample of compound has been obtained at the X- and Q-band frequencies at different temperatures. Above 20K the spectra are characteristic of S = 1 species with a zero field splitting parameter D = 0.4 cm(-1). The EPR parameters are discussed in terms of the known binuclear structures. The chemical nuclease ability of the title complex and that of the related [Cu2(tz-tol)4] compound (Htz-tol = N-thiazol-2-yl-toluenesulfonamide) is reported. The participation of hydroxyl radicals and a singlet oxygen-like entity in the DNA cleavage reaction has been deduced from the assays with radical oxygen scavengers.  相似文献   

11.
The complexation between copper(II) and the antihypertensive drug oxprenolol (HOxp) was studied both in methanol and slightly alkaline aqueous media at Cu:HOxp molar ratio from 1:1 to 1:10. Copper(lI) forms two types of complexes-a mononuclear violet one, CuOxp2, with bidentately bound ligands and a green dimeric one, Cu2Oxp2Cl2, in which the two Cu(II) centres are linked by the ligand through oxygen bridges. The crystal structure of the Cu2Oxp2Cl2 complex consists of two crystallographically non-equivalent centrosymmetric copper dimers. Each copper atom is four-coordinated in a distorted square-planar environment. The Cu2O2 structural core is characterized by a Cu1-O1-Cu1' angle of 104.15(13)degrees (Cu2-O2-Cu2' 104.30(13) degrees) and a relatively short Cu1-Cu1' separation of 3.026(1) A (Cu2-Cu2'-3.023(1) A). Magnetic susceptibility and EPR measurements indicate an antiferromagnetic coupling of the copper(II) centers.  相似文献   

12.
One new binuclear Co(II) complex of N,N,N',N'-tetrakis(2-benzimidazolylmethyl)-2-hydroxyl-1,3-diaminopropane (HL), [Co(2)L(mu(2)-Cl)](ClO(4))(2) x 3CH(3)CN x C(2)H(5)OC(2)H(5) (1), has been synthesized and its crystal structure and magnetic properties are shown. In 1, each Co(II) atom has a distorted trigonal bipyramidal geometry with a N(3)OCl donor set. The central two Co(II) atoms are bridged by one alkoxo-O atom and one Cl atom with the Co1-Co2 separation of 3.239 A. Susceptibility data of 1 indicate strong intramolecular antiferromagnetic coupling of the high-spin Co(II) atoms. In this paper, the interaction with calf thymus DNA was investigated by UV absorption and fluorescent spectroscopy. Results show the complex binds to ct-DNA with a intercalative mode. The interaction between complex 1 and pBR322 DNA has also been investigated by submarine gel electrophoresis, noticeably, the complex exhibits effective DNA cleavage activity in the absence of any external agents.  相似文献   

13.
The capacity of the ternary complex copper(II)? 1,10‐phenanthroline? L ‐serine ([Cu? Phen? Ser]) to induce double‐strand scission of DNA was explored by agarose‐gel electrophoresis. It was found that the complex exhibited remarkable activity to damage DNA in the presence of rutin. Analysis of the UV and fluorescence spectra clearly demonstrated that the complex was bound to DNA by intercalation. Further, the occurrence of 8‐hydroxydeoxyguanosine (8‐OHdG), a biomarker of oxidative DNA damage, after the treatment of DNA by the complex in presence of rutin was evidenced by an electrochemical method. Finally, the mechanism of oxidative damage to double‐stranded DNA by the [Cu? Phen? Ser] complex in the presence of rutin was discussed.  相似文献   

14.
A new quinolone-metal complex was prepared by a hydrothermal reaction in the presence of L-histidine that served as a reducing agent for a metal. The title compound [Cu(II)(cfH)(2)(Cu(I)Cl(2))(2)] (1) is a mixed-valence Cu(II)-Cu(I) complex, which contains two ciprofloxacin (cfH) molecules bonded to the central copper(II) atom and two almost planar [Cu(I)Cl(2)](-) moieties. Both metal centers are connected through two bridging atoms (chloride and quinolone oxygen). The electrochemical methods (differential-pulse polarography and cyclovoltammetric measurements) confirmed the presence of various copper-ciprofloxacin complex species in aqueous solution at low concentrations used in biological activity tests and also indicated that the equilibria in this system are very complex. The biological properties of the title compound and some previously isolated copper-ciprofloxacin complexes ([Cu(cfH)(2)Cl(2)].6H(2)O (2) and [CuCl(cfH)(phen)]Cl.2H(2)O (3)) (phen=1, 10-phenantroline) were determined and compared. The DNA gyrase inhibition tests and antibacterial activity tests have shown that the effect of copper complexes is comparable to that of free quinolone. Additionally, an interesting DNA cleavage activity of the title compound was also discovered.  相似文献   

15.
A new Mn(II) complex with the planar ligand 6,7-dicycanodipyrido[2,2-D:2',3'-f]quinoxaline (L) [MnL(NO(3))(H(2)O)(3)]NO(3).CH(3)OH (1) has been synthesized and characterized by elemental analysis, IR, TG-DTA and molar conductance. Its crystal structure was determined by X-ray diffraction, crystal data: yellow, triclinic, space group P1;, Z=2, a=7.3743(8) A, b=11.2487(15) A, c=14.1655(15) A, alpha=79.412(2) degrees, beta=83.208(2) degrees, gamma=80.466(2) degrees. The Mn atom was hexa-coordinated to form a distorted octahedral geometry by two nitrogen atoms of L and four oxygen atoms of three H(2)O and NO(3)(-) in the complex. The binding mode of the complex with calf thymus DNA has also been investigated with spectrophotometric methods, viscosity and thermal denaturation measurements. The experimental results indicate that the complex intercalated into DNA base pairs via the ligand L. The intrinsic binding constant K(b) values for 1 (5.00 x 10(5) M(-1)) and L (1.65 x 10(5) M(-1)) were determined by absorption titration and calculated with the model of McGhee and Von Hippel. Biological tests against four different cell lines (HL-60, KB, Hela and BGC-823) in vitro showed that the complex had significant antitumor properties since the 50% inhibition concentrations (IC(50)) of the complex were within a microM range similar to those of antitumor drug 5-fluorouracil.  相似文献   

16.
17.
18.
The complex μ-3,3′-[1,2-ethanediyl-bis(nitrilome- thylidyne)-bis(2-hydroxybenzoato)] aquadicopper(II) hydrate, C18H16N2O8Cu2, was isolated from an attempted preparation of a copper lanthanum binuclear complex. The dark purple crystals are monoclinic, space group P21/n, with 4 molecules per unit cell; dimensions a = 13.961(5), b = tl.787(3), c = 11.622(3) Å and β = 113.09(2)°. The final R was 0.046 for the 2062 reflections used in the analysis. The Cu atom in the N2O2 cavity is five coordinate with CuN distances of 1.879 and 1.880 Å and CuO distances of 1.898 and 1.900 Å. A water molecule at 2.557 Å completes the square pyramidal arrangement. The second Cu in the O4 cavity is square planar, with CuO distances to the bridging oxygens of 1.914 and 1.909 Å and to the carboxy oxygens of 1.871 and 1.882 Å. A survey of copper complexes in a square planar N2O2 arrangement has led to the equation δCu from the N2O2 plane = 0.822 – 0.275 (CuO axial distance) with a correlation coefficient of 0.98 for the 12 structures in which the Cu atom is bonded to a fifth oxygen atom. A model for the transition from square planar to square pyramidal geometry is proposed.  相似文献   

19.
Two new binuclear copper complexes, [Cu2(oxpn)(bpy)(pic)(H2O)](pic) (1) and [Cu2(oxpn)(Me2bpy)(pic)](pic) (2) [H2oxpn = N,N′-bis(3-aminopropyl)oxamide; Hpic = 2,4,6-trinitrophenol; bpy = 2,2′-bipyridine; Me2bpy = 4,4′-dimethyl-2,2′-bipyridine], have been synthesized and characterized by elemental analyses, conductivity measurements, IR, UV-visible spectroscopy and single crystal X-ray analyses. Both complexes have similar molecular structures. In complex 1, the central two Cu(II) atoms are bridged by cis-oxpn2− with the Cu1-Cu2 separation of 5.221 Å and the polyhedron of each copper atom is a square-pyramid. Similarly, complex 2 is a cis-oxpn2−-bridged binuclear complex with the Cu1-Cu2 separation of 5.196 Å. Cu1(II) central atom situated in a tetrahedral geometry is four-coordinated and Cu(II) atom situated in a square-pyramidal geometry is five-coordinated. Hydrogen bonding interactions and π-π stacking interactions link the binuclear copper complex 1 or 2 into a 2D infinite network. The antibacterial assays indicate that the two complexes showed better activities than their ligands. The interactions of the two binuclear complexes with herring sperm DNA (HS-DNA) have been studied by UV absorption titration, fluorescence titration and viscosity measurements. The results suggest that the two binuclear complexes bind to HS-DNA via an intercalative mode.  相似文献   

20.
A new copper complex with N-quinolin-8-yl-p-toulenesulfonamide has been prepared and characterised. The compound crystallises in the triclinic system, space group P1, with a=13.457(3), b=15.067(5), c=18.589(3) A; alpha=112.05(2), beta=93.92(2), gamma=108.30(2) degrees and Z=4. The geometry of the Cu(II) ion is distorted square planar. The N-quinolin-8-yl-p-toulenesulfonamidate anion behaves as a bidentate ligand through the N(sulfonamidate)and N(quinoline) atoms. The complex does not cleave DNA in the presence of hydrogen peroxide.  相似文献   

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