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1.
An asymmetric ligand (pdpiq?=?2-(pyridine-2-yl)-6,7-diphenyl-1-H-imidazo[4,5-g]quinoxaline) and its ruthenium complexes with [Ru(L)2pdpiq]2+ (L?=?bpy (2,2′-bipyridine) or phen (1,10-phenanthroline)) have been synthesized and characterized by elemental analysis, ES-MS, and 1H NMR. The DNA-binding behaviors of these complexes were studied by spectroscopic methods and viscosity measurements. The results indicate that the complexes can intercalate into DNA base pairs. When irradiated at 365?nm, the two complexes promote the cleavage of plasmid pBR322DNA. The mechanism of DNA cleavage is an oxidative process by generating singlet oxygen.  相似文献   

2.
3.
Two new ruthenium(II) polypyridyl complexes, [Ru(dmp)2(maip)](ClO4)2 1 (maip = 2-(3-aminophenyl)imizado[4,5-f][1,10]phenanthroline and [Ru(dmp)2(paip)](ClO4)2 2 (paip = 2-(4-aminophenyl)imidazo[4,5-f][1,10]phenanthroline, dmp = 2, 9-dimethyl-1,10-phenanthroline) have been synthesized and characterized. The DNA-binding behaviors of complexes 1 and 2 were studied by viscosity measurements, thermal denaturation, and absorption titration. The results show that the two complexes intercalate between the base pairs of DNA. The DNA-binding constants K b for complexes 1 and 2 were determined to be 3.23 ± 0.16 × 104 M−1 (s = 0.97) and 4.34 ± 0.65 × 104 M−1 (s = 1.13). The cytotoxicity of these complexes has been evaluated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. The IC50 values are 35.70, 41.04, 55.25 and 37.50 for complex 1 and 37.02, 103.08, 130.07 and 37.80 for complex 2 against BEL-7402, C-6, HepG-2 and MCF-7 cell lines, respectively. The antioxidant activity against hydroxyl radical (OH•) was also investigated.  相似文献   

4.
Ruthenium(II) polypyridyl complexes [Ru(phen)2(APIP)](ClO4)21 and [Ru(phen)2(HAPIP)](ClO4)22 have been synthesized and characterized. The DNA-binding behaviors were investigated by electronic absorption titration, luminescence spectra, viscosity measurements, thermal denaturation and photoactivated cleavage. The DNA-binding constants Kb for complexes 1 and 2 were determined to be 3.38 (±0.42) × 105 M−1 (s = 1.48) and 3.93 (±0.60) × 105 M−1 (s = 3.14), respectively. The studies on the photocleavage demonstrated that the effects of cleavage are concentration-dependent. The results showed that complexes 1 and 2 interact with CT-DNA by intercalative mode. The cytotoxicity of complexes 1 and 2 has been evaluated by MTT method. The apoptosis assay was carried out with acridine orange/ethidium bromide (AO/EB) staining methods. The cellular uptake showed that complexes can enter into the cytoplasm and accumulate in the nuclei. The antioxidant activity studies suggested that the ligands and complexes may be potential drugs to eliminate the radical.  相似文献   

5.
Polypyridyl ruthenium(II) complexes [RuII(3-bptpy)(dmphen)Cl]ClO4 (1), [RuII(3-cptpy)(dmphen)Cl]ClO4 (2), [RuII(2-tptpy)(dmphen)Cl]ClO4 (3), and [RuII(9-atpy)(dmphen)Cl]ClO4 (4) {where 3-bptpy?=?4′-(3-bromophenyl)-2,2′:6′,2″-terpyridine, 3-cptpy?=?4′-(3-chlorophenyl)-2,2′:6′,2″-terpyridine, 2-tptpy?=?4′-(2-thiophenyl)-2,2′:6′,2″-terpyridine, 9-atpy?=?4′-(9-anthryl)-2,2′:6′,2″-terpyridine, dmphen?=?2,9-dimethyl-1,10-phenanthroline} have been synthesized and characterized. The DNA-binding properties of the complexes with Herring Sperm DNA have been investigated by absorption titration and viscosity measurements. The ability of complexes to break the pUC19 DNA has been checked by gel electrophoresis. The experimental results suggest that all the complexes bind DNA via partial intercalation. The results also show that the order of DNA-binding affinities of the complexes is 4?<?3?<?2?<?1, confirming that planarity of the ligand in a complex is very important for DNA-binding.  相似文献   

6.
A new ligand, (2-ethoxy-6-(1H imadazo[4,5-f][1,10]phenanthroline-2-yl)phenol) (HEPIP) and its three Co(III) complexes [Co(phen)2(HEPIP)](ClO4)3 (1), [Co(bpy)2(HEPIP)](ClO4)3 (2) and [Co(dmb)2(HEPIP)](ClO4)3 (3) have been synthesized and characterized. All three Co(III) complexes exhibited antitumor activity against four human tumor cell lines. The interaction of these complexes with calf thymus DNA was studied by absorption and emission spectroscopy, viscosity measurements and DNA cleavage assays. The DNA-binding constants of complexes 1, 2 and 3 were determined as 6.13 × 105, 4.46 × 105 and 3.72 × 105 M?1, respectively. The complexes appear to interact with DNA through intercalation. Studies on the mechanism of photocleavage indicated that both superoxide anion radical and singlet oxygen may play an important role.  相似文献   

7.
The complexes of general formulas [RuII(terpy)(4-CO2H-4'-Mebpy)(X)]n+ (X = NO (n = 3) and NO2 (n = 1); 1, 2) and [RuII(terpy)(4-COGHK-4'-Mebpy)(X)] (X = NO (n = 3) and NO2 (n = 1); 3, 4) were synthesized and characterized. The complex [RuII(terpy)(4-CO2-4'-Mebpy)(NO2)]_7.5H2O has also been characterized by X-ray crystallographic studies. It crystallizes in the triclinic system: a = 9.4982(1) A, b = 13.1330(1) A, c = 14.2498(2) A; alpha = 110.5870(6) x bc, beta = 98.4048(5) x bc, gamma = 106.4353(5), P1, Z = 2. The crystal structure reveals an extended hydrogen-bonding network. Two water molecules form strong hydrogen bonds with the nitro and the carboxylic oxygen atoms of two separate units of the complex, resulting in a dimeric unit. The dimers are bridged by a (H2O)15 cluster, consisting of two cyclo-(H2O)6 species, while an exo-H2O(8) connects them. Two more exo-H2O molecules are joined together and connect the cyclo-(H2O)6 units with the H2O(1) of the dimeric unit. It was found that complexes 1 and 3 can be transformed into their nitro derivatives in aqueous media at neutral pH. Photorelease of NO in dry MeCN solutions was observed for complexes 1 and 3. Also, complex 2 partially releases (NO2)- in MeCN upon visible light irradiation. Complex 2 interacts with short fragments (70-300 bp) of calf thymus DNA shortening slightly the apparent polynucleotide length, while the conjugation of the peptide GHK to it (2) affects its DNA-binding mode. The peptide moiety of complex 4 was found to interact with the DNA helix in a synergistic way with the whole complex. Preliminary results of photocleavage of DNA by complex 2 are also reported.  相似文献   

8.
Zhang  Qian-Ling  Xu  Hong  Li  Hong  Liu  Jie  Liu  Jian-Zhong  Ji  Liang-Nian  Liu  Jin-Gang 《Transition Metal Chemistry》2002,27(2):149-154
Two novel complex ions [Co(bpy)2IP]3+ and [Co(bpy)2PIP]3+, have been prepared and characterized by EA, mass spectra, u.v.–vis., and cyclic voltammetry. The binding behavior of both complexes to calf thymus DNA (CT-DNA) has been investigated by spectroscopic methods, cyclic voltammetry, and viscosity measurements. The results suggest that both complexes bind to DNA by intercalation. Both promote cleavage of plasmid pBR 322 DNA from the supercoiled Form I to the open circular Form II upon irradiation. Mechanisms for photocleavage are proposed.  相似文献   

9.
The new polypyridyl ligand MIP {MIP = 2-(2,3-methylenedioxyphenyl)imidazo[4,5-f]1,10-phenanthroline} and its ruthenium(II) complexes [Ru(phen)2(MIP)]2+ (1) (phen = 1,10-phenanthroline) and [Ru(dmp)2(MIP)]2+ (2) (dmp = 2,9-dimethyl-1,10-phenanthroline) were synthesized and characterized by elemental analysis, MS and 1H NMR spectroscopy. The DNA-binding properties of the two complexes to calf-thymus DNA (CT-DNA) were investigated by different spectrophotometric methods and viscosity measurements, as well as equilibrium dialysis and circular dichroism spectroscopy. The results suggest that complex 1 binds to CT-DNA through intercalation, and complex 2 binds to CT-DNA via a partial intercalative mode. This difference in binding mode probably is caused by the different ancillary ligands. Also, when irradiated at 400 nm, complex 1 was found to be a more-effective DNA-cleaving agent than complex 2.  相似文献   

10.
Two polypyridyl ligands 6-fluro-3-(1H-imidazo [4,5-f] [1,10]-phenanthroline-2-yl)-4H-chromen-4-one (FIPC), 6-chloro-3-(1H-imidazo [4,5-f] [1,10]-phenanthroline-2-yl)-4H-chromen-4-one (ClIPC) polypyridyl ligands and their Ru(II) complexes [Ru(bipy)2FIPC]2+(1), [Ru(dmb)2FIPC]2+(2), [Ru(phen)2FIPC]2+(3), [Ru(bipy)2ClIPC]2+(4), [Ru(dmb)2ClIPC]2+(5) and [Ru(phen)2ClIPC]2+(6) ((bipy = 2,2′-bipyridine, dmb = 4,4′-dimethyl-2,2′-bipyridine and phen = 1,10-phenanthroline) have been synthesised and characterised by elemental analysis, Mass spectra, IR, 1H and 13C-NMR. The DNA-binding of the six complexes to calf-thymus DNA (CT-DNA) has been investigated by different spectrophotometric, fluorescence and viscosity measurements. The results suggest that 1–6 complexes bind to CT-DNA through intercalation. The variation in binding affinities of these complexes is rationalised by a consideration of electrostatic, steric factors and nature of ancillary ligands. Under irradiation at 365 nm, the three complexes have also been found to promote the photocleavage of plasmid pBR 322 DNA. Inhibitor studies suggest that singlet oxygen (1O2) plays a significant role in the cleavage mechanism of Ru(II) complexes. Thereby, under comparable experimental conditions [Ru(phen)2FIPC]2+(3), [Ru(phen)2ClIPC]2+(6) cleaves DNA more effectively than 1, 2, 4 and 5 complexes do. The Ru(II) polypyridyl complexes (1–6) have been screened for antimicrobial activities.  相似文献   

11.
Three ruthenium(II) polypyridyl complexes [Ru(dmb)2(dadppz)]2+ 1, [Ru(bpy)2(dadppz)]2+ 2 and [Ru(phen)2(dadppz)]2+ 3 were synthesized and characterized by elemental analysis, ES-MS, 1H NMR and 13C NMR. Their DNA-binding behaviors were investigated by absorption titration, fluorescence spectroscopy and viscosity measurements. Cytotoxicity in vitro, apoptosis, cell cycle arrest, cellular uptake and reactive oxygen species assays were performed. The complexes were found to show moderate DNA-binding affinities and high cytotoxicities toward A549, BEL-7402, MG-63 and SKBR-3 cell lines. These complexes can effectively induce apoptosis of BEL-7402. In cell cycle assays, the complexes induced S-phase arrest on BEL-7402 cells and G0/G1-phase arrest on SKBR-3 cells. The DNA-binding experiments showed that the three complexes interact with CT-DNA through an intercalative mode.  相似文献   

12.
A ligand ipdp (ipdp?=?indeno[1′,2′?:?5,6]pyrazino[2,3-i]dipyrido[3,2-a?:?2′,3′-c]phenazine-8-one) and its ruthenium complexes, [Ru(L)2(ipdp)]2+ (L?=?bpy (2,2′-bipyridine), phen (1,10-phenanthroline)), have been synthesized and characterized by elemental analysis, electrospray mass spectra, and 1H NMR. The interaction between the complexes and calf thymus DNA (CT-DNA) has been investigated by spectroscopic methods and viscosity measurements. The results indicate that the complexes can bind to CT-DNA in an intercalative mode. In addition, both complexes promote the photocleavage of plasmid pBR322 DNA under irradiation. The mechanistic studies reveal that singlet oxygen 1O2 plays a significant role in DNA photocleavage.  相似文献   

13.
Ferrocene-conjugated L-tryptophan (L-Trp) reduced Schiff base (Fc-TrpH) copper(II) complexes [Cu(Fc-Trp)(L)](ClO(4)) of phenanthroline bases (L), viz. 2,2'-bipyridine (bpy in 1), 1,10-phenanthroline (phen in 2), dipyrido[3,2-d:2',3'-f]quinoxaline (dpq in 3), and dipyrido[3,2-a:2',3'-c]phenazine (dppz in 4), were prepared and characterized and their photocytotoxicity studied. Cationic reduced Schiff base (Ph-TrpH) complexes [Cu(Ph-Trp)(L)(H(2)O)](ClO(4)) (L = phen in 5; dppz in 6) having the ferrocenyl moiety replaced by a phenyl group and the Zn(II) analogue (7) of complex 4 were prepared and used as control species. The crystal structures of 1 and 5 with respective square-planar CuN(3)O and square-pyramidal CuN(3)O(2) coordination geometry show significantly different core structures. Complexes 1-4 exhibit a Cu(II)-Cu(I) redox couple near -0.1 V and the Fc(+)-Fc couple at ~0.5 V vs SCE in DMF-0.1 M [Bu(n)(4)N](ClO(4)) (Fc = ferrocenyl moiety). The complexes display a copper(II)-based d-d band near 600 nm and a Fc-centered band at ~450 nm in DMF-Tris-HCl buffer. The complexes are efficient binders to calf thymus DNA. They are synthetic chemical nucleases in the presence of thiol or H(2)O(2), forming hydroxyl radicals. The photoactive complexes are cleavers of pUC19 DNA in visible light, forming hydroxyl radicals. Complexes 2-6 show photocytotoxicity in HeLa cancer cells, giving IC(50) values of 4.7, 10.2, 1.3, 4.8, and 4.3 μM, respectively, in visible light with the appearance of apoptotic bodies. The complexes also show photocytotoxicity in MCF-7 cancer cells. Nuclear chromatin cleavage has been observed with acridine orange/ethidium bromide (AO/EB) dual staining with complex 4 in visible light. The complexes induce caspase-independent apoptosis in the HeLa cells.  相似文献   

14.
A set of enantiomeric RuII complexes Δ- and Λ-[Ru(bpy)2TAPTP](PF6)2(bpy=2,2’-bipyridine, TAPTP=4,5,9,18-tetraazaphenanthreno[9,10-b]triphenylene) have been synthesized and characterized. Binding of both enantiomers to calf thymus DNA has been studied by spectroscopic methods, viscosity, and equilibrium dialysis. The experimental results indicated that both enantiomers bind to DNA by intercalation. Upon irradiation at 302 nm, both enantiomers were found to promote the cleavage of plasmid pBR 322 DNA from supercoiled form I to a nicked form II, and obvious enantioselectively was observed on DNA cleavage, the Λ- enantiomer exhibiting higher cleaving efficiency. The mechanisms for DNA cleavage by the two enantiomers are also proposed.  相似文献   

15.
Chan HL  Liu HQ  Tzeng BC  You YS  Peng SM  Yang M  Che CM 《Inorganic chemistry》2002,41(12):3161-3171
The synthesis and characterization of ruthenium(II) complexes, [Ru(cyclam)(bqdi)] x ZnCl(4) (1 x ZnCl(4); cyclam = 1,4,8,11-tetraazacyclotetradecane, bqdi = o-benzoquinonediimine), [Ru(cyclam)(nqdi)] x (ClO(4))(2) (2 x (ClO(4))(2); nqdi = 2,3-naphthoquinonediimine), and [Ru(cyclam)(phi)] x (ClO(4))(2) (3 x (ClO(4))(2); phi = 9,10-phenanthroquinonediimine), are described. The DNA binding properties and biological activity of the Ru(II) complexes were studied by various biophysical and cytological techniques. As expected, only 3 showed significant binding with DNA. The thermodynamic profile of the binding of 3 and DNA was constructed by analyzing the experimental data of absorption titration and UV melting studies with the McGhee equation, van't Hoff's equation, and the Gibbs-Helmholtz equation. Compound 3 binds double-stranded DNA with a binding constant of 5.0 x 10(4) M(-1) at 20 degrees C, and the binding mode of the complex to DNA was proved to be intercalative. Cytotoxicity and induced type of cell death of 1-3 were also investigated. Basically, metal complexes with ligands of molecular shape closely related to the structure of DNA are more likely to bind DNA and possess higher toxicity.  相似文献   

16.
Huang  Hong-Liang  Tang  Bing  Yi  Qiao-Yan  Wan  Dan  Yang  Lin-Lin  Liu  Yun-Jun 《Transition Metal Chemistry》2019,44(1):11-24
Transition Metal Chemistry - Five new ruthenium(II) polypyridyl complexes [Ru(N–N)2(BTCP)](ClO4)2 (BTCP?=?2-(bicyclo[2.2.1]hept-5-en-2-yl)-1H-imidazo[4,5-f][1,10]phenanthroline;...  相似文献   

17.
The synthesis, spectral characterization, and biological studies of ruthenium(II) hydrazone complexes [RuCl(CO)(PPh3)2L] (where L = hydrazone ligands) have been carried out. The hydrazones are monobasic bidentate ligands with O and N as the donors and are preferably found in the enol form in all the complexes. The molecular structure of the ligands HL1, HL2, and HL3 were determined by single-crystal X-ray diffraction. The DNA binding studies of the ligands and complexes were carried out by absorption spectroscopic and viscosity measurements. The results revealed that the ligands and complexes bind to DNA via intercalation. The DNA cleavage activity of the complexes, evaluated by gel electrophoresis assay, revealed that the complexes are good DNA cleaving agents. The antioxidant properties of the complexes were evaluated against DPPH, OH, and NO radicals, which showed that the complexes have strong radical-scavenging. Further, the in vitro cytotoxic effect of the complexes examined on HeLa and MCF-7 cancer cell lines showed that the complexes exhibited significant anticancer activity.  相似文献   

18.
Two ruthenium(II) porphyrin complexes [Ru(L)2Cl(PTP)]+ (L = bpy, 1, phen; 2; PTP = 5-(3′-pyridyl)-10,15,20-trimethylphenylporphyrin) have been synthesized and their antitumor activities have been evaluated by MTT(3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) methods. Both complexes exhibit high inhibitory activity against the growth of human cervical carcinoma cell line HeLa, both with and without light treatment. However, when treated with light, the inhibitory activity for both complexes increases at low drug concentration. Spectroscopic studies show that both complexes can bind to HeLa DNA tightly with apparent binding constants of 1.54(±0.07) × 105 and 1.01(±0.02) × 105 M−1 for 1 and 2, respectively.  相似文献   

19.
Three fluorescein-porphyrinatozinc(II) complexes, Zn(Fl-HPTTP) (1) (Fl-HPTTP?=?5-(4-fluoresceinhexyloxy)phenyl-10,15,20-tritolylporphyrin), Zn(Fl-HPTPP) (2) (Fl-HPTPP?=?5-(4-fluoresceinhexyloxy)phenyl-10,15,20-triphenylporphyrin), and Zn(Fl-HPTCPP) (3) (Fl-HPTCPP?=?5-(4-fluoresceinhexyloxy)phenyl-10,15,20-tri(4-chloro)phenylporphyrin), have been synthesized and characterized by elemental analysis, IR, UV-Vis, ES-MS, and 1H NMR. The DNA-binding behaviors of these complexes with calf-thymus DNA (ct-DNA) were investigated by UV-Vis absorption titration, fluorescence spectra, viscosity measurements, thermal denaturation, and circular dichroism. The results suggest that 1, 2, and 3 interact with ct-DNA by intercalation and the DNA-binding affinities of these fluorescein-porphyrinatozinc(II) complexes may be closely associated with electronic effects of the substituent group introduced on the porphyrin ring of the ligands. The DNA-binding affinity (K b values) follows the order 1?>?2?>?3. In addition, their photocleavage reactions with pBR322 supercoiled plasmid DNA were investigated by gel electrophoresis experiments. All complexes exhibit significant DNA cleavage activity. The cleavage ability of the fluorescein-porphyrinatozinc(II) complexes follows the order 1?>?2?>?3, in parallel to the magnitude of their intrinsic binding constants.  相似文献   

20.
DNA binding and photocleavage characteristics of a series of mixed-ligand complexes of the type [M(phen)2LL]n+ (where M = Co(III), Ni(II) or Ru(II), LL = 1,10-phenanthroline (phen), phenanthroline-dione (phen-dione) or dipyridophenazine (dppz) andn = 3 or 2) have been investigated in detail. Various physico-chemical and biochemical techniques including UV/Visible, fluorescence and viscometric titration, thermal denaturation, and differential pulse voltammetry have been employed to probe the details of DNA binding by these complexes; intrinsic binding constants (K b) have been estimated under a similar set of experimental conditions. Analysis of the results suggests that intercalative ability of the coordinated ligands varies as dppz>phen>phen-dione in this series of complexes. While the Co(II) and Ru(II) complexes investigated in this study effect photocleavage of the supercoiled pBR 322 DNA, the corresponding Ni(II) complexes are found to be inactive under similar experimental conditions. Results of detailed investigations carried out inquiring into the mechanistic aspects of DNA photocleavage by [Co(phen)2(dppz)]3+ have also been reported.  相似文献   

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