Co-reporter:Jing Qian, Shasha Yu, Wenjun Wang, Liping Wang, Jinlei Tian and Shiping Yan
Dalton Transactions 2014 vol. 43(Issue 6) pp:2646-2655
Publication Date(Web):05 Nov 2013
DOI:10.1039/C3DT51904J
A water-soluble MnIV 1,4,7-triazacyclononane complex, [MnIV2L2(μ-O)2](ClO4)2·2H2O (1), was prepared to serve as a nuclease mimic (L = 1,4,7-triazacyclononane-N-acetate). Complex 1 was readily synthesized from the highly water soluble ligand (L), with MnIII salt, [Mn3O(MeCO2)7]·3H2O in basic condition, and characterized by X-ray, IR, electronic spectroscopy, cyclic voltammetry and magnetic susceptibility as well as ESI-MS. The bond valence sum (BVS) analysis and magnetic data suggest that 1 is a MnIV–μ-O2–MnIV species. The electrospray mass spectrum and electronic spectrum of 1 in aqueous solution indicates that dinuclear Mn complex [MnIIIMnIVL2(μ-O)2]+ (2) is the active species. A predominantly hydrolytic cleavage mechanism was confirmed through experiments performed in the presence of various radical scavengers, T4 ligase and under anaerobic conditions. The kinetic aspects of DNA cleavage under pseudo- or true-Michaelis–Menten conditions were also detailed, kinetic parameters (kcat, KM, Vmax) were calculated to be 6.27 h−1, 7.35 × 10−5 M, 4.6 × 10−4 M h−1; 0.683 h−1, 1.93 × 10−5 M, 1.32 × 10−5 M h−1 for 2, respectively.
Co-reporter:Fu-Ping Huang, Peng-Fei Yao, Wei Luo, Hai-Ye Li, Qing Yu, He-Dong Bian and Shi-Ping Yan
RSC Advances 2014 vol. 4(Issue 82) pp:43641-43652
Publication Date(Web):05 Sep 2014
DOI:10.1039/C4RA03545C
To further investigate the influence of the positional isomeric ligands on structural topologies, six new coordination polymers with three positional isomeric dipyridyl ligands (4,4′-Hbpt, 3,4′-Hbpt and 3,3′-Hbpt) and trimellitic acid (H3tm), namely, {[Zn3(tm)2(4,4′-Hbpt)2(H2O)2]·10H2O}n (1), [Zn3(tm)2(3,3′-Hbpt)2]n (2), {[Cd2(tm)(3,4′-bpt)(H2O)2]·H2O}n (3), {[Cd4(tm)2(3,3′-bpt)2(H2O)2]·3H2O}n (4), {[Co3(tm)2(3,4′-Hbpt)2(H2O)6]·2H2O}n (5), {[Ni3(tm)2(3,3′-Hbpt)4(H2O)2]·7H2O}n (6), have been synthesized under hydrothermal conditions and characterized. Structural analysis reveals that: 1 and 5 both have 3D 4-connected networks, with the (4.64.8)(42.63.8)2(44.62)2 Schläfli symbol for 1 and (42.52.72)(52.62.7.8)2(4.52.6.72)2 symbol for 5. 2 and 3 both have 3D (4,5)-connected networks, with the (34.42.52)2(42.84)(3.43.52.6.72.8)2 symbol for 2 and (34.42.52)2(42.84)(3.43.52.6.72.8)2 symbol for 3. 4 has a 3D trinodal (3,4,5)-connected net with the (3.44.53.6.7) (43.62.7)(44.62)(42.6)2(45.64.8)2 symbol. And 6 has a 2D (3,4)-connected layer with (3.62)2(3.4.62.72)2(5.63.82) symbol. These results indicate that the versatile coordination modes of tm and the isomeric nature of bpt play crucial roles in modulating structural topologies of these complexes. Moreover, the luminescent properties of 1–4 and the magnetic behavior of 5–6, have been investigated.
Co-reporter:Fu-Ping Huang, Zu-Mei Yang, Peng-Fei Yao, Qing Yu, Jin-Lei Tian, He-Dong Bian, Shi-Ping Yan, Dai-Zheng Liao and Peng Cheng
CrystEngComm 2013 vol. 15(Issue 14) pp:2657-2668
Publication Date(Web):25 Jan 2013
DOI:10.1039/C3CE26905A
To further systematically investigate the influence of the positional isomeric ligands on the structures and properties of transition metal complexes, we synthesized six Cd(II) complexes with three positional isomeric dipyridyl ligands (4,4′-bpt, 3,4′-bpt and 3,3′-bpt) and three positional isomeric phenyl dicarboxylate anions (p-BDC, m-BDC and o-BDC), namely, [Cd3(p-BDC)3(4,4′-bpt)2(H2O)5]·H2O (1), [Cd(p-HBDC)(p-BDC)0.5(3,4′-bpt)] (2), [Cd4(p-BDC)4(3,3′-bpt)4]·9H2O (3), [Cd(m-BDC)(3,3′-bpt)(H2O)]·2H2O (4), [Cd(o-BDC)(3,3′-bpt)(H2O)]·(3,3′-bpt)·4H2O (5), [Cd(o-BDC)(3,4′-bpt)(H2O)]·H2O (6). Structural analysis reveals that 1 is composed of a three dimensional (3D) 4-connected net giving an interesting 3-fold interpenetrating architecture. 2 and 3 possess a similar two dimensional (2D) layer structures. 4 presents an infinite one dimensional (1D) tubular-like chain. 5 displays a 2D honeycomb structure consisting of a 1D metal–organic helical chain. 6 exhibits a 2D wave-like layer structure with a (44)-sql network. Structural diversities indicate that the nature of isomeric benzene–dicarboxylates and bpt ligands plays crucial roles in modulating structures of these complexes. Intermolecular forces have important effects on the formation and strengthening of the supra-molecular architecture in these complexes. Moreover, the luminescent properties of them have been briefly investigated.
Co-reporter:Gong-Jun Chen, Zhi-Gang Wang, Ying-Ying Kou, Jin-Lei Tian, Shi-Ping Yan
Journal of Inorganic Biochemistry 2013 Volume 122() pp:49-56
Publication Date(Web):May 2013
DOI:10.1016/j.jinorgbio.2013.01.010
A family of Phterpy complexes, [Mn(Phterpy)2][N(CN)2]2·0.5H2O (1), [Fe(Phterpy)2](NO3)2 (2), [Ni(Phterpy)2](NO3)2 (3), [Ni(Phterpy)2]Cl2·10H2O (4), [Cd(Phterpy)2](NO3)2·2H2O (5) and [Zn(Phterpy)Cl2] (6) (Phterpy = 4′-phenyl-2,2′:6′,2″-terpyridine), have been synthesized and structurally characterized, and their DNA binding and photo-induced DNA cleavage activities have been investigated. These complexes display binding propensity to the CT-DNA giving a relative order: 1 > 4 > 3, 5, 2, 6. Under dark or ambient lighting conditions, all complexes show no efficient DNA cleavage activity to pBR322 DNA. While on irradiation with UV-A light of 365 nm, complexes of 1, 3 and 4 exhibit significant cleavage activities. In the presence of H2O2 as a revulsant or an activator, the cleavage ability of complex 2 is obviously enhanced. Complexes 5 and 6 do not exhibit any apparent chemical nuclease activities under irradiation conditions or with the addition of H2O2. The DNA photo-induced cleavage activities are consistent with the number of single-electron in the central metal ion of complexes and singlet oxygen and hydroxyl radical are found as the reactive oxygen species.In attempt to obtain more insight on the selectivity and efficiency of DNA cleavage with different transition metal complexes, herein, we have prepared a series of mononuclear d-metal complexes and investigated their DNA cleavage activities.Highlights► A family of Phterpy complexes have been synthesized and structurally characterized. ► Their DNA binding and photo-induced DNA cleavage activities have been studied. ► Singlet oxygen and hydroxyl radical are found as the reactive oxygen species.
Co-reporter:Gong-Jun Chen, Zhi-Gang Wang, Xin Qiao, Jing-Yuan Xu, Jin-Lei Tian, Shi-Ping Yan
Journal of Inorganic Biochemistry 2013 Volume 127() pp:39-45
Publication Date(Web):October 2013
DOI:10.1016/j.jinorgbio.2013.06.002
•Some lanthanide-based complexes have been synthesized and structurally characterized.•The compounds exhibit efficience photo-induced DNA cleavage activities.•The compounds have the potential to act as effective anticancer drugs.As a continuing investigation of our previous studies about the influence of the different rare earth metal ions on the bioactivity, a family of heavy rare earth metal complexes, [RE(acac)3(dpq)] (RE = Tb (1), Dy (2), Ho (3), Er (4), Tm (5), Yb (6), Lu (7)) and [RE(acac)3(dppz)]·CH3OH (RE = Tb (8), Dy (9), Ho (10), Er (11), Tm (12), Yb (13), Lu (14) viz. acetylacetonate (acac), dipyrido[3,2-d:20,30-f]quinoxaline (dpq), dipyrido[3,2-a:20,30-c] phenazine (dppz)), has been synthesized and their biological activities were also investigated. On the irradiation with UV-A light of 365 nm or ambient light, all complexes exhibit efficient DNA cleavage activity via the mechanistic pathway involving the formation of singlet oxygen and hydroxyl radical as the reactive species. In addition, the in vitro cytotoxicity of these complexes on HeLa cells has been examined by MTT assay, which indicate that these compounds have the potential to act as effective anticancer drugs. The results of the above biological experiments also reveal that the choice of different rare earth metal ions has little influence on the DNA binding, DNA cleavage and cytotoxicity.A family of heavy rare earth complexes, [RE(acac)3(dpq)] and [RE(acac)3(dppz)]CH3OH have been synthesized, their DNA binding and photo-induced DNA cleavage activity are investigated.DNA binding, DNA cleavage and cytotoxicity not have affected by rare earth metal elements.
Co-reporter:Fu-Ping Huang, Peng-Fei Yao, Qing Yu, Di Yao, He-Dong Bian, Hai-Ye Li, Jin-Lei Tian, Shi-Ping Yan
Inorganic Chemistry Communications 2013 Volume 31() pp:18-22
Publication Date(Web):May 2013
DOI:10.1016/j.inoche.2013.02.012
A 2-D cobalt–organic framework formulated as [Co(bdc)(bptb)]n (1), built from a mixed 1,2-benzenedicarboxylate anion (bdc), 1,4-bis(5-(4-pyridyl)-1H-1,2,4-triazol-3-yl)benzene (bptb), and cobalt salt, has been hydrothermally synthesized and characterized. Complex 1 has a [Co(bdc)]n chain structure in which the chains are isolated by the bptb ligands in a 2-D wave-like architecture. The magnetic behavior of complex 1 was studied, and it indicated the coexistence of spin-canted weak ferromagnetism with TN = 10 K and long-range magnetic ordering.Graphical abstractIn this paper, a 2-D Cobalt-organic framework formulated as [Co(bdc)(bptb)]n (1), built from a mixed 1,2-benzenedicarboxylate anion (bdc), 1,4-bis(5-(4-pyridyl)-1H-1,2,4-triazol-3-yl)benzene (bptb), and cobalt salt, has been hydrothermally synthesized and characterized. Complex 1 indicated the coexistence of spin-canted weak ferromagnetism with TN = 10 K and long-range magnetic ordering.Highlights► A 2-D coordination polymers with new mixed-ligand system have been synthesized. ► Complex 1 indicated spin-canted weak ferromagnetism with TN = 10 K, and long-range magnetic ordering. ► Bptb is a long bent linker.
Co-reporter:Jing-Yuan Xu, Hai-Bin Song, Gong-Feng Xu, Xin Qiao, Shi-Ping Yan, Dai-Zheng Liao, Yves Journaux and Joan Cano
Chemical Communications 2012 vol. 48(Issue 7) pp:1015-1017
Publication Date(Web):21 Nov 2011
DOI:10.1039/C1CC16243H
An enneanuclear nickel(II) complex with a rectangular face-centered trigonal prism structure bridged by μ2-pyrazolate, μ6-CO32− and μ3-OH−groups was synthesized. It displays cluster glass-like magnetic behavior assigned to the single molecule magnet properties of {Ni9} clusters and weak intercluster interaction.
Co-reporter:Fu-Ping Huang, Qian Zhang, Qing Yu, He-Dong Bian, Hong Liang, Shi-Ping Yan, Dai-Zheng Liao, and Peng Cheng
Crystal Growth & Design 2012 Volume 12(Issue 4) pp:1890-1898
Publication Date(Web):March 1, 2012
DOI:10.1021/cg201577w
Four bent ligands, (i) 4,4′-abpt, (ii) 4,4′-Hbpt, (iii) 3,4′-Hbpt, and (iv) 3,3′-Hbpt, as well as H2suc (succinic acid) have been utilized to construct seven coordination polymers: [Co(suc)(4,4′-abpt)(H2O)2]·H2O (1), [M(suc)(4,4′-Hbpt)(H2O)]·2H2O (M = Co for 2, Ni for 3), [Cd(suc)(4,4′-Hbpt)2(H2O)2] (4), [Co(suc)(3,4′-Hbpt)(H2O)3]·H2O (5), [Zn(suc)(3,4′-Hbpt)] (6), and [Zn(suc)0.5(3,3′-bpt)(H2O)] (7) (4,4′-abpt = 4-amino-3,5-bis(4-pyridyl)-1,2,4-triazole, 4,4′-Hbpt = 1H-3,5-bis(4-pyridyl)-1,2,4-triazole, 3,4'-Hbpt = 1H-3-(3-pyridyl)-5-(4-pyridyl)-1,2,4-triazole, and 3,3′-Hbpt = 1H-3,5-bis(3-pyridyl)-1,2,4-triazole). The crystal structure analysis reveals that 1–3 form similar two-dimensional (2D) layer structures, where the adjacent metal centers are connected by a syn–anti carboxylate bridge from suc ligands to furnish a succinate-metal chain, which is further interlinked by bent ligands. 4–7 form different 1D chains via suc anions, and bpt isomers display versatile coordination modes. The magnetic behavior of compounds 1–3 and 5 was studied, and it indicated the existence of interesting spin-canting behavior, where the bent ligands tilting the neighbor metal center could give further contribution to the canting effect. In addition, the luminescent properties of 4, 6, and 7 have been investigated in the solid state at room temperature.
Co-reporter:Chun-Yan Gao, Xin Qiao, Zhong-Ying Ma, Zhi-Gang Wang, Jing Lu, Jin-Lei Tian, Jing-Yuan Xu and Shi-Ping Yan
Dalton Transactions 2012 vol. 41(Issue 39) pp:12220-12232
Publication Date(Web):30 Jul 2012
DOI:10.1039/C2DT31306E
Three new zinc(II) complexes: [Zn2(L1)2Cl2](ClO4)2·C2H5OH (1) and [Zn2L2X4]·2CH3CN (X = Br for 2, Cl for 3), utilizing two new and interrelated di-nucleating polypyridyl ligands (L1, L2), have been synthesized and characterized by using various physico-chemical techniques. The interactions of three complexes with CT-DNA have been explored by using absorption, emission and CD spectral methods, which reveal that three complexes bind to CT-DNA by partial intercalation binding modes. Notably, in the presence of H2O2 as a revulsant or an activator, the cleavage abilities of all complexes are obviously enhanced. The hydrolytic mechanism was demonstrated by adding standard radical scavengers and anaerobic reaction. Further, the protein binding ability has been monitored by quenching of tryptophan emission in the presence of complexes using BSA as a model protein. The quenching mechanisms of BSA by the complexes are static procedures. In addition, the in vitro cytotoxicity of the complexes on three human tumor cells lines (HeLa, MCF-7 and RL952) and the apoptosis-inducing activity of 3 were assessed by MTT, Clonogenic assay, Hoechst 33342 staining, Cell cycle and Annexin V binding experiments.
Co-reporter:Fu-Ping Huang, Hai-Ye Li, Qing Yu, He-Dong Bian, Jin-Lei Tian, Shi-Ping Yan, Dai-Zheng Liao and Peng Cheng
CrystEngComm 2012 vol. 14(Issue 14) pp:4756-4766
Publication Date(Web):19 Apr 2012
DOI:10.1039/C2CE25586C
The hydrothermal reactions of a bent ligand, 1H-3,5-bis(4-pyridyl)-1,2,4-triazole (bpt), with Co/Ni(II) ions as well as a series of polycarboxylate co-ligands yielded five new coordination polymers, namely, {[Co2(fum)2(bpt)2(H2O)]·3H2O}n (1), {[Co(mal)(bpt)0.5(H2O)]·1.5H2O}n (2), {[Co2(bptc)(bpt)2(EtOH)(H2O)2]·2H2O}n (3), [Ni2(btc)(bpt)2(H2O)2]·6H2O (4), [Ni2(Hbidc)2(bpt)2]·7H2O (5) (here, H2fum = fumaric acid, H2mal = malonic acid, H4bptc = 3,3′,4,4′-benzophenone-tetracarboxylate acid, H4btc = 1,2,4,5-benzenetetracarboxylate acid, H3bidc = 1H-benzimidazole-5,6-dicarboxylic acid). These complexes exhibit different architectures and magnetic behaviors: 1 has a 3D (3,5)-connected (42·6)(42·65·83) topology, showing field-induced spin-flop transition; 2 and 3 both have a (3,4)-connected topology, exhibiting normal antiferromagnetism, with a 3D (63)(63·83) symbol for 2and a 2D (62·8)2(64·82) symbol for 3, respectively. In 4 and 5, the topological analysis results reveal that 4 can be simplified to a 3D 4-connected NbO net, while 5 is a 3D trinodal (3,4,6)-connected (63)(65·8)(612·8·102) net. Both 4 and 5 exhibit spin-canted antiferromagnetism.
Co-reporter:Gong-Jun Chen, Xin Qiao, Chun-Yan Gao, Guang-Jun Xu, Zhi-Ling Wang, Jin-Lei Tian, Jing-Yuan Xu, Wen Gu, Xin Liu, Shi-Ping Yan
Journal of Inorganic Biochemistry 2012 Volume 109() pp:90-96
Publication Date(Web):April 2012
DOI:10.1016/j.jinorgbio.2011.12.009
A family of light rare earth complexes, [RE(acac)3(dpq)] (RE = La (1), Ce (2), Pr (3), Nd (4), Sm (5)) and [RE(acac)3(dppz)].CH3OH (RE = La (6), Ce (7), Pr (8), Nd (9), Sm (10) viz. acetylacetonate (acac), dipyrido[3,2-d:20,30-f]quinoxaline (dpq), dipyrido[3,2-a:20,30-c] phenazine (dppz)), have been synthesized and structurally characterized. Binding interactions of these complexes with CT-DNA and their photo-induced DNA cleavage activity with pBR 322 DNA are also investigated. These complexes have strong DNA binding interaction (Kb ≈ 105 M− 1 and Kapp ≈ 105 M− 1)and the binding propensity to CT-DNA decrease with the order: dppz complexes > dpq complexes. Furthermore, DNA photocleavage experiments indicate that these complexes are efficient DNA cleaving agents in UV-A (365 nm) and ambient light in the absence of any external reagents. Hydroxyl radical (HO•) and singlet oxygen (1O2) are the major cleavage active species from the machanistic studies. Moreover, cell cytotoxicity studies of these complexes on HeLa, K562 and MDA-MB-231 cells indicate that they have the potential to act as effective metal-based anti-cancer drugs.A family of light rare earth complexes, [RE(acac)3(dpq)] and [RE(acac)3(dppz)]CH3OH have been synthesized and their DNA binding and photo-induced DNA cleavage activity are investigated.The light rare earth metal elements have less effect in the DNA binding, DNA cleavage and cytotoxicity.
Co-reporter:Zhi-gang Wang;Ying-ying Kou;Jing Lu;Chun-yan Gao;Jin-lei Tian
Applied Organometallic Chemistry 2012 Volume 26( Issue 10) pp:511-517
Publication Date(Web):
DOI:10.1002/aoc.2889
A novel oxalato-bridged copper(II) complex has been prepared and structurally characterized: [Cu(bpa)(μ-C2O4)].H2O (bpa = bis(2-pyridylmethyl) amine). In the complex, the copper ion is linked in an unusual μ1,2,3-C2O42− bridging mode, generating one-dimensional zigzag chain disposition. Variable-temperature magnetic susceptibility studies (2–300 K) reveal a weak ferromagnetic coupling, J = 0.63 cm−1, between the copper ions. The interaction of the complex with CT-DNA has been studied using UV–visible absorption and emission spectral methods, and the binding constant of the complex with CT-DNA is Kapp = 9 × 104 m−1, which indicates that the interaction of the complex with DNA is a moderate intercalative mode. Furthermore, the complex cleaves supercoiled plasmid DNA efficiently in the presence of hydrogen peroxide. The mechanistic investigations suggest that the hydroxyl radical and singlet oxygen are involved in the DNA degradation. Copyright © 2012 John Wiley & Sons, Ltd.
Co-reporter:Gong-Jun Chen;Yun-Nan Guo;Dr. Jin-Lei Tian;Dr. Jinkui Tang;Dr. Wen Gu;Dr. Xin Liu; Shi-Ping Yan;Dr. Peng Cheng; Dai-Zheng Liao
Chemistry - A European Journal 2012 Volume 18( Issue 9) pp:2484-2487
Publication Date(Web):
DOI:10.1002/chem.201103816
Co-reporter:Gong-Jun Chen, Chun-Yan Gao, Jin-Lei Tian, Jinkui Tang, Wen Gu, Xin Liu, Shi-Ping Yan, Dai-Zheng Liao and Peng Cheng
Dalton Transactions 2011 vol. 40(Issue 20) pp:5579-5583
Publication Date(Web):18 Apr 2011
DOI:10.1039/C1DT10050E
By changing the ratio of reactants, two mononuclear Dy complexes, [Dy(phen)(acac)3] (1) and [Dy(phen)2(NO3)2(acac)]·H2O (2) have been synthesized and structurally characterized. In 1, a Dy atom bearing square-antiprism coordination geometry exhibits SMM behaviour, while compound 2 with a bicapped-square-antiprism geometry does not show such SMM properties. The different magnetic behaviours seen in 1 and 2 are probably due to a different coordination environment and ligand field around the Dy(III) ions. The results proved the important influence of the structural environment of a SMM on its magnetic behaviour.
Co-reporter:Fu-Ping Huang, He-Dong Bian, Qing Yu, Jin-Lei Tian, Hong Liang, Shi-Ping Yan, Dai-Zheng Liao and Peng Cheng
CrystEngComm 2011 vol. 13(Issue 21) pp:6538-6548
Publication Date(Web):01 Sep 2011
DOI:10.1039/C1CE05562C
Hydrothermal reactions of 1,1′-biphenyl-2,2′-dicarboxylic acid (H2dpa) with Co(II), Ni(II) Mn(II) and Zn(II) salts, and systematically varied N-donor co-ligands (positional isomeric dipyridyl bridging ligands: 4,4′-bpt, 3,4′-bpt and 3,3′-bpt), lead to the formation of a series of supramolecular complexes, namely, [Co(dpa)(4,4′-bpt)(EtOH)(H2O)] (1), [Ni(dpa)(4,4′-bpt)(H2O)2]·2.5H2O (2), [Cu(dpa)(4,4′-bpt)(H2O)]·2H2O (3), [M(dpa)(3,4′-bpt)]·H2O (M = Co for 4, Ni for 5, Mn for 6, and Zn for 7, respectively), [Zn3(OH)2(dpa)2 (3,3′-bpt)2]·2H2O (8) (where 4,4′-bpt = 1H-3,5-bis(4-pyridyl)-1,2,4-triazole, 3,4′-bpt = 1H-3-(3-pyridyl)-5-(4-pyridyl)-1,2,4-triazole and 3,3′-bpt = 1H-3,5-bis(3-pyridyl)-1,2,4-triazole). Structural analysis reveals that dpa manages the M(II) (M = Co, Ni, Mn and Zn) ions to form 1-D chains, which are further extended via the isomeric bpt connectors in different directions, to give rise to a variety of coordination polymers of 1–8. Magnetic susceptibilities of complexes 1–6 reveal the weak antiferromagnetic or ferromagnetic exchange interactions between the adjacent metal centers. Moreover, the luminescent properties of 7–8 have been briefly investigated.
Co-reporter:Gong-Jun Chen, Xin Qiao, Pei-Qi Qiao, Guang-Jun Xu, Jing-Yuan Xu, Jin-Lei Tian, Wen Gu, Xin Liu, Shi-Ping Yan
Journal of Inorganic Biochemistry 2011 Volume 105(Issue 2) pp:119-126
Publication Date(Web):February 2011
DOI:10.1016/j.jinorgbio.2010.11.008
Two new Cu(II) complexes, [Cu(acac)(dpq)Cl] (1) and [Cu(acac)(dppz)Cl] (2) (acac = acetylacetonate, dpq = dipyrido[3,2-d:20,30-f]quinoxaline, dppz = dipyrido[3,2-a:20,30-c] phenazine), have been synthesized and their DNA binding, photo-induced DNA cleavage activity and cell cytotoxicity are studied. The complexes show good binding propensity to calf thymus DNA in the order: 2(dppz) > 1(dpq). Furthermore, two complexes exhibit efficient DNA cleavage activity on natural light or UV-A (365 nm) irradiation via a mechanistic pathway involving formation of singlet oxygen as the reactive species. The photo-induced DNA cleavage activity of the dppz complex 2 is found to be more efficient than its dpq analogue. In vitro study of the photocytotoxicity of two complexes on HeLa cells indicate that both of them have the potential to act as effective anticancer drugs, with IC50 values of 5.25 ± 0.83 μM (1) and 4.40 ± 0.52 μM (2) in the natural light, and 2.57 ± 0.92 μM (1) and 2.18 ± 0.52 μM (2) in UV-A light. In addition, to detect an apoptotic HeLa body, cells were stained with Hoechst 33342 dye.Copper(II) complexes with planar heterocyclic bases are prepared. The DNA cleavage experiments show singlet oxygen as the reactive species. The cytotoxicity of the complexes against HeLa cancer cell evaluated and the HeLa cell died through an apoptosis process induced by complexes which indicates that the complexes 1 and 2 are promising drugs for cancer.
Co-reporter:Dong-Dong Li, Jin-Lei Tian, Wen Gu, Xin Liu, Hui-Hui Zeng, Shi-Ping Yan
Journal of Inorganic Biochemistry 2011 Volume 105(Issue 6) pp:894-901
Publication Date(Web):June 2011
DOI:10.1016/j.jinorgbio.2011.03.012
Three new binuclear copper(II) complexes have been synthesized and structurally characterized by X-ray crystallography, [Cu2(1,4-tpbd)(dafo)2(MeOH)2](ClO4)4·2.5H2O (1), [Cu2(1,4-tpbd) (DMSO)2(ClO4)2](OH)2·6H2O (2) and [Cu2(1,4-tpbd)(OAC)2(ClO4)2]·5H2O (3) (1,4-tpbd = N,N,N′,N′-tetrakis(2-pyridylmethyl)benzene-1,4-diamine). Complex 1 to 3 shows similar binuclear structure and each Cu atom adopts five-coordinated square-pyramidal geometry. The interactions of the three complexes with CT-DNA (Calf-thymus DNA) have been investigated by UV absorption, fluorescence spectroscopy, circular dichroism spectroscopy and viscosity. Furthermore, the three complexes display oxidative cleavage of supercoiled DNA in the presence of external agents. Complex 3 shows higher DNA affinity and nuclease activity may be attributed to its cis structural configuration and labile acetate and perchlorate anions. The cleavage mechanisms between the complexes and plasmid DNA are likely to involve singlet oxygen or singlet oxygen-like entity as reactive oxygen species. In addition, in vitro cytotoxicity studies on the Hela cell line show that the IC50 values of complexes 1–3 are 14.75, 13.67 and 16.58 μM, respectively. The apoptosis-inducing activity was also assessed by AO/EB (Acridine Orange/Ethidium bromide) staining assay, indicating they have the potential to act as effective metal-based anticancer drugs.Three new binuclear copper(II) complexes with 1,4-tpbd exhibit significant cytotoxic activities with the IC50 values of complexes 1–3 are 14.75, 13.67 and 16.58 μM. The apoptosis-inducing activity was assessed by AO/EB staining assay, indicating they have the potential to act as effective metal-based anticancer drugs.
Co-reporter:Fu-Ping Huang ; Jin-Lei Tian ; Dong-Dong Li ; Gong-Jun Chen ; Wen Gu ; Shi-Ping Yan ; Xin Liu ; Dai-Zheng Liao ;Peng Cheng
Inorganic Chemistry 2010 Volume 49(Issue 5) pp:2525-2529
Publication Date(Web):February 4, 2010
DOI:10.1021/ic9024348
A 3D nickel−organic framework formulated as {[Ni2(fum)2(bpt)2(H2O)]·3H2O}n (1), built from a mixed fumaric ion (fum), 1H-3,5-bis(4-pyridyl)-1,2,4-triazole (bpt), and nickel salt, has been hydrothermally synthesized and characterized. Compound 1, having a Ni−fum chain structure in which the chains are pillared by the bpt spacers in a 3D “brick-wall”-like architecture, exhibits canted antiferromagnetism at 5.0 K. Below this temperature, slow relaxation is observed from the alternating-current susceptibility measurements corresponding to the spin-glass-like behavior.
Co-reporter:Fu-Ping Huang, Jin-Lei Tian, Wen Gu, Xin Liu, Shi-Ping Yan, Dai-Zheng Liao and Peng Cheng
Crystal Growth & Design 2010 Volume 10(Issue 3) pp:1145-1154
Publication Date(Web):February 4, 2010
DOI:10.1021/cg901014r
To systematically investigate the influence of the positional isomeric ligands on the structures and magnetic properties of their complexes, we synthesized ten Co(II) complexes with three positional isomeric dipyridyl ligands (4,4′-bpt, 3,4′-bpt and 3,3′-bpt), as well as the phenyl dicarboxylate anions, namely, [Co(o-BDC)(4,4′-bpt)(H2O)] (1), [Co(o-BDC)(3,3′-bpt)(H2O)] (2), [Co(3-Cl-o-BDC)(4,4′-bpt)(H2O)] (3), [Co(3-Cl-o-BDC)(3,4′-bpt)] (4), [Co(m-BDC)(3,4′-bpt)] (5), [Co(m-BDC)(3,3′-bpt)]·H2O (6), [Co2(5-NO2-m-BDC)2(3,4′-bpt)(H2O)4] (7), [Co(5-NO2-m-BDC)(3,3′-bpt)]·H2O (8), [Co(p-BDC)(3,4′-bpt)2(H2O)2]·2H2O (9), and [Co(p-BDC)(3,3′-bpt)2(H2O)2]·2H2O (10) (o-BDC = 1,2-benzenedicarboxylate anion, 3-Cl-o-BDC = 3-Cl-1,2-benzenedicarboxylate anion, m-BDC = 1,3-benzenedicarboxylate anion, 5-NO2-m-BDC = 5-NO2-1,3-benzenedicarboxylate anion, p-BDC = 1,4-benzenedicarboxylate anion). Structural analysis reveals that the phenyl dicarboxylate anions display versatile coordination modes to manage the Co(II) ions to form 1-D chains or 2-D layers, which are further extended via the isomeric bpt connectors in different directions, to give rise to a variety of coordination polymers, such as 2-D square 44-sql layer (for 1−5), 3-D CsCl net (for 6), 2-D honeycomb 63-hcb layer (for 7), 1-D double chain (for 8), and 1-D decorated chain (for 9−10). This work indicates that the isomeric effects of the bpt ligands are significant in the construction of these network structures, based on same Co(II) centers. Furthermore, these compounds exhibit different magnetic behaviors. In 1−3, although Co(II) ions have the similar structural characteristic, the phenomenon of spin-canting in 2 can be observed more easily than 1 and 3, which may reveal that the different orientations of the pyridyl groups in bpt isomer have a profound impact on the magnetic properties of the solids. In 4, 5, and 7, which all are bridged by asymmetric 3,4′-bpt ligand, spin-canting in 7 can be observed more easily than 4 and 5 because the adjacent Co(II) ions are related to a inversion center in 4 and 5. Moveover, there are approximate isotropic Co(II) ions in 4. In addition, the magnetic behavior of compounds 6 and 8 was also studied and indicated the existence of antiferromagnetic interactions.
Co-reporter:Fu-Ping Huang, Jin-Lei Tian, Gong-Jun Chen, Dong-Dong Li, Wen Gu, Xin Liu, Shi-Ping Yan, Dai-Zheng Liao and Peng Cheng
CrystEngComm 2010 vol. 12(Issue 4) pp:1269-1279
Publication Date(Web):17 Dec 2009
DOI:10.1039/B915506F
To systematically investigate the influence of the positional isomeric ligands on the structures and properties of transition metal complexes, we synthesized eight Zn(II) complexes with three positional isomeric carboxylate ligands (p-BDC, m-BDC and o-BDC) and three positional isomeric dipyridyl bridging ligands (4,4′-bpt, 3,4′-bpt and 3,3′-bpt). {[Zn2(p-BDC)2(4,4′-bpt)2]·H2O·(C2H5OH)}n (1), {[Zn(p-BDC)(3,4′-bpt)2(H2O)2]·2H2O}n (2), {[Zn(p-BDC)(3,3′-bpt)2(H2O)2]·3H2O}n (3), {[Zn2(m-BDC)2(4,4′-bpt)(H2O)3]·H2O}n (4), [Zn(m-BDC)(3,4′-bpt)]n (5), {[Zn(m-BDC)(3,3′-bpt)]·H2O}n (6), [Zn(o-BDC)(4,4′-bpt)]n (7) and [Zn2(o-BDC)2(3,4′-bpt)]n (8) (p-BDC = 1,4-benzenedicarboxylate anion, m-BDC =1,3-benzenedicarboxylate anion, o-BDC = 1,2-benzenedicarboxylate anion, 4,4′-bpt = 1H-3,5-bis(4-pyridyl)-1,2,4-triazole, 3,4′-bpt = 1H-3-(3-pyridyl)-5-(4-pyridyl)-1,2,4-triazole and 3,3′-bpt = 1H-3,5-bis(3-pyridyl)-1,2,4-triazole). Structural analysis reveals that the benzenedicarboxylate isomers display versatile coordination modes to manage the Zn(II) ions to form 1D chains (for 2–5, 7 and 8) or 2D layers (for 1 and 6), which are further extended via the isomeric bpt connectors in different directions to give rise to a variety of coordination polymers, such as 1D decorated chain, 1D ladder-like chain, 2D sql layer, 2D bilayer with 82·10 topology, 2D wave-like layer, 3D 2-fold interpenetrating porous pcu net and 3D CsCl net. These results indicate that the nature of isomeric benzenedicarboxylates and bpt ligands has an important effect on the structural topologies of such Zn(II) complexes. Moreover, the luminescent properties of the complexes have been briefly investigated.
Co-reporter:Gong-Jun Chen, Xin Qiao, Jin-Lei Tian, Jing-Yuan Xu, Wen Gu, Xin Liu and Shi-Ping Yan
Dalton Transactions 2010 vol. 39(Issue 44) pp:10637-10643
Publication Date(Web):04 Oct 2010
DOI:10.1039/C0DT00718H
Two Eu(III) complexes, [Eu(acac)3(dpq)] (1) and [Eu(acac)3(dppz)] CH3OH (2) {viz. acetylacetonate (acac), dipyrido[3,2-d:20,30-f]quinoxaline (dpq), dipyrido[3,2-a:20,30-c] phenazine (dppz)}, have been synthesized and their DNA binding, photo-induced DNA cleavage activity and cell cytotoxicity are studied. The complexes display significant binding propensity to the calf thymus DNA in the order: 2(dppz) >1(dpq). Cleavage experiments using pBR322 supercoiled DNA suggest major groove binding for 2 and minor groove binding for 1. The mechanistic aspects on natural light (natural light in room during the day) and UV-A (365 nm) irradiation are via a mechanistic pathway involving formation of singlet oxygen and hydroxyl radical as the reactive species. The photo-induced DNA cleavage activity of 2 is also stronger than 1. The cytotoxicity of 1 and 2 against HeLa (cervical) cancer cells show that the IC50 value of 19.11 ± 3.56 μM and 17.95 ± 5.47 μM, respectively.
Co-reporter:Fu-Ping Huang, Jin-Lei Tian, Dong-Dong Li, Gong-Jun Chen, Wen Gu, Shi-Ping Yan, Xin Liu, Dai-Zheng Liao and Peng Cheng
CrystEngComm 2010 vol. 12(Issue 2) pp:395-400
Publication Date(Web):11 Sep 2009
DOI:10.1039/B911950G
A novel (3,4,6)-connected 3D porous cobalt–organic framework formulated as {[Co2(Hbidc)2(bpt)2]·7H2O}n (1) (H3bidc = 1H-benzimidazole-5,6-dicarboxylic acid, bpt = 1H-3,5-bis(4-pyridyl)-1,2,4- triazole) has been hydrothermally synthesized and characterized by X-ray diffraction analysis. Compound 1, having a Co-Hbidc layer structure in which the layers are pillared by the bpt spacers in a 3D architecture, exhibits the coexistence of spin-canted weak ferromagnetism with TN = 10 K and long-range magnetic ordering.
Co-reporter:Dong-Dong Li, Jin-Lei Tian, Wen Gu, Xin Liu, Shi-Ping Yan
Journal of Inorganic Biochemistry 2010 Volume 104(Issue 2) pp:171-179
Publication Date(Web):February 2010
DOI:10.1016/j.jinorgbio.2009.10.020
A novel binuclear copper(II) complex [Cu2L(μ-SO4)](PF6)2 (1) (L = 3,5-bis (bis(pyridine-2-ylmethyl)amino)methyl)-4H-1,2,4-triazol-4-amine) has been synthesized and structurally characterized. X-ray structure shows that the two copper(II) atoms are bridged by one bidentate sulfate ion and the 1,2,4-triazole ring of L with Cu1⋯Cu2 distance of 4.404 Å. Each copper(II) center has a distorted trigonal–bipyramidal configuration. Variable-temperature magnetic susceptibility studies (2–300 K) indicate the existence of weak antiferromagnetic coupling between the copper(II) ions in complex 1. The interaction of complex 1 with calf thymus DNA (CT-DNA) has been studied by UV absorption, fluorescence spectroscopy, circular dichroism spectroscopy, viscosity and cyclic voltammetry. Furthermore, complex 1 was able to promote single and double strand DNA cleavage in both aerobic and anaerobic conditions, the pseudo-Michaelis–Menten kinetic parameters kcat = 2.58 h−1 and Km = 1.2 × 10−4 M were obtained for 1. The hydrolytic cleavage of DNA by the complex was supported by the evidence from free radical quenching, anaerobic experiment, thiobarbituric acid-reactive substances (TBARS) assay.
Co-reporter:Jing Qian, Xiaofang Ma, Jinlei Tian, Wen Gu, Jing Shang, Xin Liu, Shiping Yan
Journal of Inorganic Biochemistry 2010 Volume 104(Issue 9) pp:993-999
Publication Date(Web):September 2010
DOI:10.1016/j.jinorgbio.2010.05.005
Three water-soluble dicobalt(III) complexes, [Co2L2(µ-OH)2](ClO4)2·5H2O (1), [Co2L2(µ-OH)2](ClO4)2·CH3OH·H2O(2); [Co2L2(µ-OH)2](ClO4)2·4H2O(3) (L = 1,4,7-triazacyclononane-N-acetate monoanion), were prepared to serve as nuclease mimics. The complexes were characterized by X-ray, IR and UV–vis spectroscopy as well as ESI-MS. Three complexes exhibit similar structures, just with different solvent molecules. The electrospray mass spectrum of 1 in solution indicates that dinuclear ion [Co2L2(µ-OH)2-H+] + (4) is the active species. In the absence of any reducing agent, the complexes cleave plasmid pBR322 DNA was performed and its hydrolytic mechanism was demonstrated with radical scavengers, anaerobic reaction and T4 ligase. The kinetic aspects of DNA cleavage under pseudo- or true-Michaelis–Menten conditions are also detailed, kinetic parameters (kcat, KM) were calculated to be 3.57 h− 1, 6.92 × 10− 4 M; 0.28 h− 1, 1.9 × 10− 5 M for 4, respectively.Three μ-hydroxo dimmer complexes were designed and characterized to serve as nuclease mimics. DNA cleavage promoted by the complex was demonstrated to occur by a hydrolytic ways double-strand pathways.
Co-reporter:Dong-Dong Li, Fu-Ping Huang, Gong-Jun Chen, Chun-Yan Gao, Jin-Lei Tian, Wen Gu, Xin Liu, Shi-Ping Yan
Journal of Inorganic Biochemistry 2010 Volume 104(Issue 4) pp:431-441
Publication Date(Web):April 2010
DOI:10.1016/j.jinorgbio.2009.12.008
Four copper(II) complexes [Cu2(1,3-tpbd)Cl4]·EtOH (1), {[Cu2(1,3-tpbd)(μ-Cl)2](ClO4)2(H2O)4.5 (NaClO4)}∞ (2), [Cu2(1,3-tpbd)(1,10-phen)2(H2O)2](ClO4)4 (3) and [Cu2(1,3-tpbd)(2,2′-bpy)2(H2O)2](ClO4)4 (4) (1,3-tpbd = N,N,N′,N′-tetrakis(2-pyridylmethyl)benzene-1,3-diamine) have been synthesized and characterized by X-ray single crystal structure analysis. Variable–temperature magnetic susceptibility studies (2–300 K) indicate the existence of antiferromagnetic coupling between the copper(II) ions in complexes 2 and 3. The interactions of the four complexes with calf thymus DNA (CT-DNA) have been investigated by UV absorption, fluorescent spectroscopy, circular dichroism spectroscopy, viscosity and cyclic voltammetry, and the modes of CT-DNA binding to the complexes have been proposed. Furthermore, DNA cleavage activities by the four complexes were performed in the presence and absence of external agents, the results indicate that their cleavage activities have been promoted in the presence of external agents. Mechanism investigation shows that the four complexes could cleave DNA through both oxidative and hydrolytic processes. In the four copper(II) complexes, complex 2 showed highest cleavage activity with the pseudo-Michaelis–Menten kinetic paraments kcat = 5.16 h−1 and Km = 3.6 × 10−5 M.Spectroscopic and gel electrophoresis methods revealed that four new copper(II) complexes showed high DNA-binding and cleavage activities. Complex 2 has the highest nuclease activity with the pseudo-Michaelis–Menten kinetic paraments kcat = 5.16 h−1 and Km = 3.6 × 10−5 M.
Co-reporter:Fu-Ping Huang, Jin-Lei Tian, Wen Gu, Shi-Ping Yan
Inorganic Chemistry Communications 2010 Volume 13(Issue 1) pp:90-94
Publication Date(Web):January 2010
DOI:10.1016/j.inoche.2009.10.025
Based on 1,2,4,5-benzenetetracarboxylate acid (H4btc), and mixed with three isomeric dipyridyl ligands, three novel 3D Cu(II) coordination polymers [Cu2(btc)(4,4′-bpt)]·2H2O (1) [4,4′-bpt = 1H-3,5-bis(4-pyridyl)-1,2,4-triazole], [Cu(btc)0.5(3,4′-bpt)]·0.5H2O (2)[3,4′-bpt = 1H-3-(3-pyridyl)-5-(4-pyridyl)-1,2,4- triazole] and [Cu(btc)0.5(3,3′-bpt)]·2H2O (3) [3,3′-bpt = 1H-3,5-bis(3-pyridyl)-1,2,4-triazole] have been synthesized and characterized, respectively. 1 is a 3D pillared double-layer complex containing a novel bilayer unit; 2 is a 3D pillared-layer architecture with (4,4)-sql layer; 3 exhibits a 3D structure containing 3D [Cu(btc)]∞ motif and 1D [Cu(bpt)]∞ chain. The topological analysis shows that 1 can be simplified to a (4,6)-connected network with the Schläfli symbol of (42·64)2(48·67), 2 a (4,6)-connected network with the symbol of (44·62)(44·610·8), and 3 a four-connected topology with the symbol of (32·103·11)2(32·104).Three novel three-dimensional coordination polymers [Cu2(btc)(4,4′-bpt)]·2H2O (1), [Cu(btc)0.5(3,4′-bpt)]·0.5H2O (2) and [Cu(btc)0.5(3,3′-bpt)]·2H2O (3), based on 1,2,4,5-benzenetetracarboxylate acid and three positional isomeric bridging ligands, are prepared and topologically analyzed.
Co-reporter:Hui Liu;Ying-ying Kou;Li Feng;Dong-dong Li;Chun-Yan Gao;Jin-lei Tian;Jing-yan Zhang
Applied Organometallic Chemistry 2010 Volume 24( Issue 9) pp:636-640
Publication Date(Web):
DOI:10.1002/aoc.1659
Abstract
Two new mononuclear iron(III) complexes, [Fe(HL)2](ClO4) · (H2O)1.75· CH3CN (1) and [Fe(HL)Cl2] · DMF (2) [H2L = 3-(2-phenol)-5-(pyridin-2-yl)-1,2,4-triazole] have been synthesized and characterized by X-ray single-crystal structure analysis. The single crystal X-ray crystallographic studies reveal that the central iron atom has a distorted octahedral environment for 1 and a distorted square pyramidal geometry for 2. The DNA cleavage activity of the iron(III) complexes was measured, indicating that the six-coordinated iron(III) (complex 1) was cleavage inactive and only five-coordinated complex 2 effectively promoted the cleavage of plasmid DNA in the presence and/or absence of activating agents (peroxide oxygen) at physiological pH and temperature. The mechanism of plasmid DNA cleavage was also studied by adding standard radical scavengers. Copyright © 2010 John Wiley & Sons, Ltd.
Co-reporter:Dongdong Li, Jinlei Tian, Yingying Kou, Fuping Huang, Gongjun Chen, Wen Gu, Xin Liu, Daizheng Liao, Peng Cheng and Shiping Yan
Dalton Transactions 2009 (Issue 18) pp:3574-3583
Publication Date(Web):18 Mar 2009
DOI:10.1039/B823472H
Four new copper(II) complexes, [Cu(1,4-tpbd)Br2] (1), [Cu2(1,4-tpbd)(H2O)4](ClO4)4 (2), [Cu2(1,4-tpbd)(1,10-phen)2(DMF)2](ClO4)4 (3) and [Cu2(1,4-tpbd)(2,2′-bpy)2(ClO4)2](ClO4)2 (4), [1,4-tpbd = N,N,N′,N′-tetrakis(2-pyridylmethyl)benzene-1,4-diamine], have been synthesized to serve as artificial nucleases. Single crystal X-ray diffraction reveals that the copper(II) atom has a distorted intermediate between square pyramidal and trigonal bipyramidal configuration for 1 and a distorted square pyramidal geometry for 2, while a distorted octahedral environment for 3 and 4. Variable-temperature magnetic susceptibility studies (2–300 K) indicate the existence of antiferromagnetic coupling between the copper(II) ions in complex 2. The interactions of the four complexes with calf thymus DNA (CT-DNA) have been investigated by UV absorption, fluorescent spectroscopy and cyclic voltammetry, and the modes of CT-DNA binding for the complexes have been proposed. In the absence of external agents, supercoiled plasmid DNA cleavage by the complexes was performed under aerobic conditions, the influence on the DNA cleavage process of different complex concentrations, reaction times was also studied. The DNA cleavage mechanisms were demonstrated with radical scavengers and anaerobic conditions, indicating all complexes cleaved pBR322 DNA in 50 mM Tris-HCl/18 mM NaCl buffer (pH = 7.2) at 37 °C through a hydrolytic process. In the four copper(II) complexes, complex 2 showed highest cleavage activity with the pseudo-Michaelis–Menten kinetic parameters kcat = 4.23 h−1 and Km = 2.4 × 10−5 M.
Co-reporter:Yingying Kou, Jinlei Tian, Dongdong Li, Wen Gu, Xin Liu, Shiping Yan, Daizheng Liao and Peng Cheng
Dalton Transactions 2009 (Issue 13) pp:2374-2382
Publication Date(Web):09 Feb 2009
DOI:10.1039/B819052F
Five binuclear Schiff base copper(II) complexes [Cu2(L)(OAc)]·3DMF (1), [Cu2(L)(OAc)]2·3DMF (2), [Cu2(L)(BNPP)]·3CH3CN (3), [Cu2(L)(Fa)]·2DMF (4) and [Cu2(L)(Pa)]·DMF (5) (H3L = N,N′-bis(3,5-tert-butylsalicylidene-2-hydroxy)-1,3-propanediamine, OAc = acetic acid, BNPP = bis(4-nitrophenyl)phosphate, Fa = 2-tetrahydrofuroic acid, Pa = benzoic acid) have been synthesized and characterized by X-ray single-crystal structure analysis. Variable-temperature magnetic susceptibility studies (2–300 K) indicate the existence of ferromagnetic coupling between the copper(II) ions in complexes 1 and 4, and antiferromagnetic coupling in complexes 3 and 5. The interaction of these complexes with CT-DNA has been studied by using absorption and emission spectral methods. The apparent binding constant (Kapp) values for complexes 1, 3, 4 and 5 are 4.67 × 105, 9.48 × 105, 4.30 × 105 and 3.90 × 105 M−1, respectively, which show that the complexes bind to DNA by moderate intercalative binding modes. Furthermore, all these complexes can cleave plasmid DNA to nicked DNA in a sequential manner as the concentrations or reaction times are increased in the absence of reducing agent. Their cleavage activities are promoted in the presence of hydrogen peroxide. The cleavage mechanisms between the complexes and plasmid DNA are likely to involve singlet oxygen 1O2 and ˙OH as reactive oxygen species.
Co-reporter:Hui Liu, Jinlei Tian, Yingying Kou, Jingyan Zhang, Li Feng, Dongdong Li, Wen Gu, Xin Liu, Daizheng Liao, Peng Cheng, Joan Ribas and Shiping Yan
Dalton Transactions 2009 (Issue 47) pp:10511-10517
Publication Date(Web):19 Oct 2009
DOI:10.1039/B904553H
This paper reports the synthesis, crystal structures, and magnetic properties of a series of mixed-valence polynuclear manganese complexes bridged by a dianionic 1,2,4-triazole-based ligand L2− (H2L = 3-(2-phenol)-5-(pyridin-2-yl)-1,2,4-triazole). Complexes 1 to 3 show a similar binuclear structure, with the central core of [MnIIMnIII(L)2] and some other small molecules also coordinated to the two Mn centers. The two [MnIIMnIII(L)2] subunits can be further connected by different dicarboxylic acids to construct non-charged tetranuclear complexes 4 to 7. In these complexes, each deprotonated dianionic ligand L2− acts as a μ2-bridged ligand to coordinate two Mn centers via the 1,2,4-triazole ring. Bond valence sum (BVS) calculations and Mn surrounding bond lengths indicate that the Mn center coordinated to the pyridine N atoms in the +2 oxidation state, while another Mn center coordinated to the phenolic O atoms is in the +3 oxidation state. The MnIII centre shows Jahn–Teller elongation along one of the axes. Magnetic studies show the presence of ferromagnetic MnIII–MnII coupling in the binuclear (1–3) and tetranuclear (4–7) complexes with the magnetic coupling constant (J) ranging from 0.58 to 1.17 cm−1, based on the Hamiltonian H = −2JS1·S2 (S1 = 5/2 and S2 = 2). In all cases both z′J′ (intermolecular interactions) and D parameter (Zero Field Splitting of the Mn (III) ion) has been introduced to improve the corresponding fit. The relationship of the coupling interaction between the MnII/MnIII and their electronic structures is discussed.
Co-reporter:Gong-Jun Chen, Feng-Xian Gao, Fu-Ping Huang, Jin-Lei Tian, Wen Gu, Xin Liu, Shi-Ping Yan and Dai-Zheng Liao
Crystal Growth & Design 2009 Volume 9(Issue 6) pp:2662
Publication Date(Web):April 22, 2009
DOI:10.1021/cg801227e
Three types of Na+-mediated hybrid transition metal−alkali complexes possessing special architectures with molecular formulas of [Na(H2O)3(μ-L)Mn](MnL)(ClO4)3·9H2O·(2H3O+) (2), [Na5Mn2(μ-L)2](ClO4)5(H2O)6 (3) and [Na(NiL)2](ClO4)2·5H2O(3H3O+) (4) (H3L = 1,4,7-triazacyclononane-N,N′,N′′-tripropionic acid) were self-assembled from a reaction system containing transition metal, alkali metal and H3L, and were isolated under different crystallization conditions. In these complexes, [ML] units were connected by Na+ ions to form varied 2D layer structures. Na+ ions act as templates for inducing the organization of [ML] moieties into respective special architectures in different fashions. As a comparison, a mononuclear complex [MnL]2[Mn(H2O)6](ClO4)3·8H2O (1) has been isolated without Na+ ions in the reaction system. This fact proved that sodium ions play a vital role in the assembly procedure. These four complexes have been characterized by elemental analysis, IR, UV spectroscopy and single-crystal X-ray diffraction.
Co-reporter:Fu-Ping Huang, Hai-Ye Li, Jin-Lei Tian, Wen Gu, Yi-Min Jiang, Shi-Ping Yan and Dai-Zheng Liao
Crystal Growth & Design 2009 Volume 9(Issue 7) pp:3191
Publication Date(Web):May 27, 2009
DOI:10.1021/cg801243a
The preparations via variation of the reactive conditions of the same metal-to-ligand ratios of Co(NO3)2·6H2O with mixed l-cysteic acid (H2cys) and 4,4′-bipyridine (bpy) ligands gave rise to two interesting pillared supramolecular isomers: {[Co2(cys)2(bpy)2(H2O)2]·3H2O}n (1) and {[Co2(cys)2(bpy)(H2O)4](bpy)·H2O}n (2), which have the same formula but distinct solid phases. In the two complexes, Co(II) centers are chelated and bridged by different μ2-cys bridges to form a one-dimensional (1D) 41 helical chain and a 1D zigzag chain, respectively. The two chains are further linked by bpy pillars into a novel three-dimensional (42.84)-lvt structrue (1) and a two-dimensional brick-wall structure (2), respectively. The magnetic behavior of compounds 1 and 2 was studied, and it indicated the existence of small antiferromagnetic coupling. Best fit parameters for 1: J = −0.14 K with R = 4.77 × 10−4; for 2, J = −0.64 K with R = 3.62 × 10−4.
Co-reporter:Dong-Dong Li;Jin-Lei Tian;Wen Gu;Xin Liu
European Journal of Inorganic Chemistry 2009 Volume 2009( Issue 33) pp:5036-5045
Publication Date(Web):
DOI:10.1002/ejic.200900763
Abstract
Two novel 1,2,4-triazole-based copper(II) complexes have been synthesized and structurally characterized by X-ray crystallography: [Cu2LCl3]·0.5[CuCl4]·EtOH (1) and [Cu2LBr3]·Br·H2O (2) (L = 3,5-bis{[bis(2-methoxyethyl)amino]methyl}-4H-1,2,4-triazol-4-amine). Single-crystal diffraction reveals that the two Cu atoms have a distorted octahedral geometry for 2, but one Cu atom is in a distorted square-pyramidal environment and the other one is in a distorted octahedral environment for 1 because of the different bridged halogen atoms. The interactions of the two complexes with calf thymus DNA (CT-DNA) have been investigated by UV absorption, fluorescence spectroscopy, circular dichroism spectroscopy, viscosity measurements and cyclic voltammetry. The apparent binding constant (Kapp) values for complexes 1 and 2 are 2.98 × 106 and 4.05 × 106M–1. Furthermore, both the compounds display efficient oxidative cleavage of supercoiled DNA in the presence of external agents. The rate constants for the conversions of supercoiled to nicked DNA are 4.38 × 10–4 s–1 (for 1) and 5.26 × 10–4 s–1 (for 2). (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2010)
Co-reporter:Xiao-Fang Ma;Dong-Dong Li;Jin-Lei Tian;Ying-Ying Kou
Transition Metal Chemistry 2009 Volume 34( Issue 5) pp:475-481
Publication Date(Web):2009 August
DOI:10.1007/s11243-009-9219-7
Three new reduced amino-acid Schiff base complexes, [Co(HL)2(H2O)2] · 4H2O (1), [Cu(HL)2(H2O)2] · 2H2O (2), and [Cd(HL)2(H2O)3] · 2H2O (3), where H2L is the reduced Schiff-base ligand derived from the condensation of N-(4-hydroxybenzaldehyde) with L-glycine, have been synthesized and characterized by physico-chemical and spectroscopic methods. In these complexes, the two bidentate monoanionic Schiff base ligands coordinate the metal center through the secondary amine N atom and the carboxylate O atom. Water ligands complete a distorted octahedral (1, 2) or a pentagonal bipyramidal coordination geometry (3) around each metal center. The binding interactions of the complexes with CT-DNA have been investigated by UV–visible spectrophotometry and fluorescence quenching methods. The results show that these complexes bind to CT-DNA with an intercalative mode. In addition, DNA cleavage experiments have been also investigated by agarose gel electrophoresis. Complexes 1–3 show oxidative DNA cleavage activity in the presence of H2O2/sodium ascorbate and the reactive oxygen species responsible for the DNA cleavage is most likely singlet oxygen.
Co-reporter:Jing-Yuan Xu, Xin Qiao, Hai-Bin Song, Shi-Ping Yan, Dai-Zheng Liao, Song Gao, Yves Journaux and Joan Cano
Chemical Communications 2008 (Issue 47) pp:6414-6416
Publication Date(Web):07 Nov 2008
DOI:10.1039/B813705F
A novel octanuclear hydroxonickel(II) complex possessing a unprecedented cube molecular structure with eight Ni(II) ions at each vertex, six µ4-OH−groups closing each face and twelve exo-bidentate pyrazolate ligands (µ2-pz) spanning each edge, has been synthesized and its magnetic properties investigated.
Co-reporter:Jing Qian, Jinlei Tian, Wen Gu, Song Gao, Liu Xin, Shiping Yan, Joan Ribas, Daizheng Liao and Peng Cheng
Dalton Transactions 2008 (Issue 48) pp:6948-6952
Publication Date(Web):18 Oct 2008
DOI:10.1039/B808916G
A new FeIII6cluster, [Fe3L2(ida)(μ-OH)3(μ-O)]2·4ClO4·2CH3OH·8H2O (1) (where L = N-methyl-N,N-bis(2-pyridylmethyl)amine; H2ida = iminodiacetic acid), has been synthesized and magnetic properties are shown. The asymmetric unit of 1 contains a triangular [Fe3L2(ida)(μ-OH)3(μ-O)]2+ unit and two such trinuclear units are further connected by two ida2−, generating a hexanuclear FeIII core in 1. Variable temperature magnetic susceptibility studies reveal the presence of dominant antiferromagnetic exchange interactions and the variable-field and temperature magnetization measurements establish that each Fe3 cluster has S = 5/2 ground state and the coupling between the two moieties is almost zero.
Co-reporter:Xiao-Fang Ma, Jin-Lei Tian, Wen Gu, Song Gao, Shi-Ping Yan, Dai-Zheng Liao
Inorganic Chemistry Communications 2008 Volume 11(Issue 3) pp:256-259
Publication Date(Web):March 2008
DOI:10.1016/j.inoche.2007.11.019
One chiral heptanuclear FeIII cluster, {Fe[(FeL)2(μ2-OH)]3(μ2-OH)6} · 13H2O (1) (H2L=N-(2-hydroxybenzyl)-l-histidine), has been synthesized and characterized structurally and magnetically. Complex 1 crystallizes in the chiral space group C2. The heptanuclear FeIII cluster of 1 has a propeller-like [Fe7(μ2-OH)9]12+ core, with the peripheral ligation provided by six tetradentate L2− ligands. The configurations of the C- and the N-centers of L2− is (S, R) and the central atom Fe4 is chiral Λ configuration. All FeIII centers are hexacoordinated, displaying a distorted octahedral coordination sphere. Variable temperature magnetic studies showed complex 1 is antiferromagnetic with C = 14.27 cm3 K mol−1 and θ = −27.56 K. Magnetisation and susceptibility measurements show that cluster 1 exhibits a ground spin state of S = 3.One new chiral heptanuclear FeIII cluster, {Fe[(FeL)2(μ2-OH)]3(μ2-OH)6} · 13H2O (1), has been synthesized and characterized structurally and magnetically. The heptanuclear FeIII cluster of 1 has a propeller-like [Fe7(μ2-OH)9]12+ core, with the peripheral ligation provided by six tetradentate L2− ligands. Variable temperature magnetic studies showed 1 is antiferromagnetic with C = 14.27 cm3 K mol−1 and θ = −27.56 K.
Co-reporter:Jing-Yuan Xu, Jin-Lei Tian, Qing-Wei Zhang, Jing Zhao, Shi-Ping Yan, Dai-Zheng Liao
Inorganic Chemistry Communications 2008 Volume 11(Issue 8) pp:943
Publication Date(Web):August 2008
DOI:10.1016/j.inoche.2008.04.003
Co-reporter:Jing-Yuan Xu, Jin-Lei Tian, Qing-Wei Zhang, Jing Zhao, Shi-Ping Yan, Dai-Zheng Liao
Inorganic Chemistry Communications 2008 Volume 11(Issue 1) pp:69-72
Publication Date(Web):January 2008
DOI:10.1016/j.inoche.2007.10.016
Use of pyrophosphate, 2,2′-dipyridylamine (hdpa) with Cu(NO3)2 · 3H2O has enabled to synthesize a novel tetranuclear copper(II) complex, [Cu4(hdpa)4(μ-P2O7)2] · 11H2O 1, which was characterized by single crystal X-ray diffraction, IR, ESR spectrum, and variable-temperature magnetic susceptibilities (4.2–300 K). Extensive π–π stackings and H-bonding water clusters resulting from 11 free water molecules join Cu4 units to make a 3D network. According to the molecular structure, the experimental data were fitted to the expressions derived from the Hamiltonian H=-2J12S^1S^2-2J13(S^1S^3+S^2S^4)-2J14(S^1S^4+S^2S^4) showing dominant antiferromagnetic behaviors.Use of pyrophosphate, 2,2′-dipyridylamine with Cu(NO3)2 · 3H2O has enabled the synthesis of two copper(II) complexes, tetranuclear [Cu4(hdpa)4(μ-P2O7)2] · 11H2O with extensive π–π stackings and H-bonding water clusters and polymer single-helical structure [Cu(hdpa)(HPO4)]n, under different reaction conditions; magnetic studies reveal that the tetranuclear one has dominant antiferromagnetic behavior.
Co-reporter:Guangjun Xu;Wen Gu;Xiaofang Ma;Li Feng;Shiping Yan
Frontiers of Chemistry in China 2008 Volume 3( Issue 2) pp:138-142
Publication Date(Web):2008 June
DOI:10.1007/s11458-008-0026-z
The interaction between CT-DNA and a ternary copper (II) complex, [Cu(phendio)(L-Phe)(H2O)](ClO4)·H2O (CuPP, phendio = 1,10-phenanthroline-5,6-dione, L-Phe = L-phenylalanine), has been conducted by electronic spectra, fluorescence spectroscopy and cyclic voltammetry. It has been found that the max. absorption peak from the electronic spectra is red shifted and the intensity is weakened and that the values of peak current from cyclic voltammetry are decreased significantly in the presence of DNA compared with that in the absence of DNA. At the same time, the complex can quench the emission intensity of EB-DNA system. The existence of the intercalation mode between the complex and DNA was proven. By submarine gel electrophoresis, we found that the copper(II) complex can cleave circular plasmid pBR322 DNA into nicked and linear forms in the presence of ascorbic acid and H2O2.
Co-reporter:Mingjin Xie, Guangjun Xu, Ling Li, Weiping Liu, Yanfen Niu, Shiping Yan
European Journal of Medicinal Chemistry 2007 Volume 42(Issue 6) pp:817-822
Publication Date(Web):June 2007
DOI:10.1016/j.ejmech.2006.12.021
[N,N′-1,3-Propyl-bis(salicyladimine)]oxovanadium(IV) – an oxovanadium complex has been tested for bioactivity as an insulin-enhancing agent. Its structure reveals that the vanadium(IV) ion is hexacoordinated and situated in a distorted octahedral environment. The complex was administered intragastrically to both normal and streptozotocin (STZ)-diabetic rats for two weeks. The results showed that the complex, at a dose of 10.0 and 20.0 mg V·kg−1, could lower the blood glucose level in STZ-diabetic rats and improve the response to an oral glucose challenge. This complex did not alter these parameters in normal rats. It was suggested that the complex exerted an antidiabetic effect in STZ-diabetic rats.[N,N′-1,3-Propyl-bis(salicyladimine)]oxovanadium (IV) – an oxovanadium complex has been tested for bioactivity as an insulin-enhancing agent. The complex was administered intragastrically to both normal and streptozotocin (STZ)-diabetic rats for two weeks. The results show that in STZ-diabetic rats the complex at a dose of 10.0 and 20.0 mg V kg−1, could lower the basal blood glucose level in rats and improve the response to an ig glucose challenge. It was suggested that the complex exerted an antidiabetic effect in STZ-diabetic rats.
Co-reporter:Jing Qian, Wen Gu, Hui Liu, Fengxian Gao, Li Feng, Shiping Yan, Daizheng Liao and Peng Cheng
Dalton Transactions 2007 (Issue 10) pp:1060-1066
Publication Date(Web):07 Feb 2007
DOI:10.1039/B615148E
Two novel binuclear complexes [Cu2(L)]·(ClO4)2 (1) and [Zn2(L)]·(ClO4)2 (2) were synthesized and crystallographically characterized {L = 14,54-dimethyl-12,52-dihydroxy-1(1,3),5(1,3)-dibenzene-3(1,4),7(1,4)-di-1,4,7-triazacyclononane}. The cation [Cu2(L)]2+ structure of 1 is similar to that of [Zn2(L)]2+ of 2. The central ion is bridged by the di-phenoxo of L and lies in a close to perfect square pyramidal geometry. 1 and 2 crystallize in the triclinic space group P. The two complexes effectively promote the cleavage of plasmid DNA in the presence of activating agents at physiological pH and temperature. The pseudo-Michaelis–Menten kinetic parameters kcat = 1.61 h−1, Km = 1.35 × 10−5 M for complex 1 in the presence of mercaptoethanol; kcat = 2.48 h−1, Km = 5.5 × 10−5M for complex 2 in the presence of hydrogen peroxide were obtained. The mechanism of plasmid DNA cleavage was studied by adding standard radical scavengers. DNA cleavage reaction by the binuclear Zn(II)/H2O2 system is a hydrolytic mechanism.
Co-reporter:Jin-Lei Tian, Li Feng, Wen Gu, Guang-Jun Xu, Shi-Ping Yan, Dai-Zheng Liao, Zong-Hui Jiang, Peng Cheng
Journal of Inorganic Biochemistry 2007 Volume 101(Issue 2) pp:196-202
Publication Date(Web):February 2007
DOI:10.1016/j.jinorgbio.2006.08.009
One new binuclear Co(II) complex of N,N,N′,N′-tetrakis(2-benzimidazolylmethyl)-2-hydroxyl-1,3-diaminopropane (HL), [Co2L(μ2- Cl)](ClO4)2 · 3CH3CN · C2H5OC2H5 (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 N3OCl 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 Å. 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.
Co-reporter:Feng-Xian Gao;Wen Gu;Jing Qian;Yong-Sheng Yang
Applied Organometallic Chemistry 2007 Volume 21(Issue 5) pp:
Publication Date(Web):2 APR 2007
DOI:10.1002/aoc.1214
A new complex {[Na2(H2O)3(µ-L)2Cu]4}∞ (L = N-methyliminodiacetic acid) has been synthesized and structurally characterized. The complex crystallizes in the monoclinic, space group C2/c, with the unit cell parameters a = 16.556(3) Å, b = 8.0622(13) Å, c = 12.671(2) Å, α = 90°, β = 95.849(2)°, γ = 90°. The central metal Cu (II) ion is coordinated with two nitrogen atoms and four oxygen atoms belonging to two ligands. Simultaneously, the sodium is six-coordinated with oxygen atoms coming from the ligand and water molecule; the sodium atoms related are bridged by oxygen atoms, forming a sodium chain. The structure consists of CuL2 moieties linked by sodium chain via the exo oxygen atoms of two ligands, forming a novel three-dimensional structure. Moreover, elemental analysis, IR, UV-vis, ESR spectroscopy and thermal stability were determined. Copyright © 2007 John Wiley & Sons, Ltd.
Co-reporter:Jing-Yuan Xu;Jin-Lei Tian;He-Dong Bian;Dai-Zheng Liao;Peng Cheng;Pan-Wen Shen
Applied Organometallic Chemistry 2007 Volume 21(Issue 3) pp:
Publication Date(Web):30 JAN 2007
DOI:10.1002/aoc.1199
A new dialkoxo-bridged diiron(III) complex, [Fe2(BMA)2(CH3O)2Cl2]·2Cl·4CH3OH (1) [BMA = N,N-bis(2-benzimidazolylmethyl)amine], was synthesized and characterized by UV-visible absorption and infrared spectra and magnetic susceptibilities. The complex crystallizes in the monoclinic system, space group P2(1)/n, a = 12.9659(19) Å, b = 10.0278(16) Å, c = 17.919(2) Å, β = 93.766(8)° , V = 2324.8(6) Å3, Z = 2, F(000) = 1036, Dc = 1.426 g cm−3, µ = 0.908 mm−1. According to X-ray crystallographic studies, each Fe(III) ion lies in a highly distorted octahedral environment, and two Fe(III) ions are bridged by the methoxyl oxygens. Cryomagnetic analyses indicated a moderate antiferromagnetic interaction between the high-spin Fe(III) ions, with J = − 27.05 cm−1. Moreover, the binding interaction of DNA with the diiron complex was investigated by spectroscopic and agarose gel electrophoretic methods, showing moderate cleavage activity on pBR322 plasmid DNA at physiological pH and temperature. Copyright © 2007 John Wiley & Sons, Ltd.
Co-reporter:Jing Qian;Qing-Lun Wang;Wen Gu;Jin-Lei Tian;Ming-Jin Xie
Transition Metal Chemistry 2007 Volume 32( Issue 7) pp:847-850
Publication Date(Web):2007 October
DOI:10.1007/s11243-007-0204-8
Two novel μ-oxo-di-μ-carboxylato-bridged iron(III) complexes of [Fe2(bpea)2(PhCO2)2(μ-O)] (ClO4)2·C2H5OH (1) and [Fe2(bpma)2(ClCH2COO)2(μ-O)](ClO4)2· H2O (2) (bpea = N,N-bis(2-pyridylmethyl)ethylamine, bpma = N,N-bis(2-pyridylmethyl)methylamine), have been synthesized and determined by X-ray diffraction. Complex (1) crystallizes in the Orthorhombic space group Pnma with d(Fe···Fe) of 3.094 Å and average d(Fe–Obbridge) of 1.805 Å; Complex (2) crystallizes in the Monoclinic space group C2/c, with d(Fe···Fe) of 3.109 Å and average d(Fe–Obbridge) of 1.794 Å. The magnetic studies indicate a stronger antiferromagnetic interaction between iron(III) ions through μ-oxo-di-μ-carboxylato-bridge for complex (1), with J = − 141.6 cm−1.
Co-reporter:Guang-Jun Xu;Ying-Ying Kou;Li Feng;Dai-Zheng Liao;Zong-Hui Jiang;Peng Cheng
Applied Organometallic Chemistry 2006 Volume 20(Issue 5) pp:
Publication Date(Web):1 MAY 2006
DOI:10.1002/aoc.1064
Syntheses, and electrochemical properties of two novel complexes, [Cu(phendio)(L-Phe)(H2O)](ClO4) ·H2O (1) and [Ni(phendio)(Gly)(H2O)](ClO4)·H2O (2) (where phendio = 1,10-phenanthroline-5,6-dione, L-Phe = L-phenylalanine, Gly = glycine), are reported. Single-crystal X-ray diffraction results of (1) suggest that this complex structure belongs to the orthorhombic crystal system. The electrochemical properties of free phendio and these complexes in phosphate buffer solutions in a pH range between 2 and 9 have been investigated using cyclic voltammetry. The redox potential of these compounds is strongly dependent on the proton concentration in the range of − 0.3–0.4 V vs SCE (saturated calomel reference electrode). Phendiol reacts by the reduction of the quinone species to the semiquinone anion followed by reduction to the fully reduced dianion. At pH lower than 4 and higher than 4, reduction of phendio proceeds via 2e−/3H+ and 2e−/2H+ processes. For complexes (1) and (2), being modulated by the coordinated amino acid, the reduction of the phendio ligand proceeds via 2e−/2H+ and 2e−/H+ processes, respectively. Copyright © 2006 John Wiley & Sons, Ltd.
Co-reporter:Mingjin Xie, Lihui Gao, Ling Li, Weiping Liu, Shiping Yan
Journal of Inorganic Biochemistry 2005 Volume 99(Issue 2) pp:546-551
Publication Date(Web):February 2005
DOI:10.1016/j.jinorgbio.2004.10.033
Bis(α-furancarboxylato)oxovanadium(IV) – a new orally active antidiabetic vanadyl complex has been synthesized, characterized, and tested for bioactivity as insulin-enhancing agents. The complex was administered intragastrically to both normal and STZ-diabetic rats for 4 weeks. The results show that the complex at a dose of 10.0 and 20.0 mg V kg−1, could significantly lower the blood glucose level rats and ameliorated impaired glucose tolerance in STZ-diabetic, but not in normal rats. It was suggested that the complex exerted an antidiabetic effect in STZ-diabetic rats, which maybe was related to increasing the sensitivity to insulin.
Co-reporter:Tian Jin-Lei;Xie Ming-Jin;Yan Shi-Ping;Liao Dai-Zheng;Jiang Zong-Hui;Cheng Peng
Chinese Journal of Chemistry 2005 Volume 23(Issue 5) pp:
Publication Date(Web):14 JUN 2005
DOI:10.1002/cjoc.200590525
By using the tripodal tetradentate ligands of tris(2-pyridylmethyl)amine (TPA) or tris(2-benzimidazolylmethyl)amine (NTB), two dinunclear iron(III) complexes [Fe2L2(μ2-O)(μ2-p-NH2-C6H4COO)]3+ (L=TPA, 1 and L=NTB, 2) were obtained. Both of the two complexes crystallize in monoclinic system with space group P2(1)/c. The cell parameters of 1: a=1.4529(4) nm, b=1.6622(5) nm, c=2.0625(6) nm, β=100.327(5)°, V=4.900(3) nm3, Z=4, F(000)=2344, Mr=1142.91, Dc=1.549 g/cm3, R1=0.0544, R2=0.0962. The cell parameters of 2: a=1.3378(4) nm, b=2.1174(7) nm, c=2.4351(7) nm, β=97.315(6)°, V=6.842(4) nm3, Z=4, F(000)=3116, Mr=1505.08, Dc=1.444 g/cm3, R1=0.0793, R2=0.1623. In both cases, the central iron(III) metal ions are coordinated to the four nitrogen atoms of TPA (or NTB) and two oxygen atoms from two different bridges to form a distorted octahedral geometry.
Co-reporter:Zhao-Dong Wang, Wei Han, Fang Bian, Zhan-Quan Liu, Shi-Ping Yan, Dai-Zheng Liao, Zong-Hui Jiang, Peng Cheng
Journal of Molecular Structure 2005 Volume 733(1–3) pp:125-131
Publication Date(Web):3 January 2005
DOI:10.1016/j.molstruc.2004.08.016
Two new one-dimensional copper(II) complexes bridged by azide and thiocyanate, [Cu(DACO)(μ-1,1-N3)(μ-1,3-N3)]n (1) and [Cu(DACO)(μ-NCS)(NCS)]n (2), where DACO=1,5-diazacyclooctane, have been synthesized and characterized. Single crystal X-ray diffraction analysis reveals that the bridging azido groups in complex 1 are coordinated alternately in the single end-to-end and single end-on models, giving an alternate chain, the unbridged N3− groups acted as the terminal ligands. In complex 2, the strictly alternating copper ions and thiocyanates produce a chain in which the metallic centers are connected through single end-on-end NCS− groups. The central copper(II) ions in both complexes are penta-coordinated and situated in a distorted square-pyramid environment. Low temperature magnetic susceptibility indicates that complex 1 shows an antiferromagnetic behavior with the value for exchange coupling constant J is −4.06 cm−1, and g=2.038; while the complex 2 exhibits a weak ferromagnetic interactions between the copper ions with J=1.04 cm−1 and the corresponding g=2.03. Moreover, the two complexes have also been characterized on the basis of elemental analysis, IR and UV–vis spectroscopy.
Co-reporter:Wei Han;Long Yi;Zhan-Quan Liu;Wen Gu;Peng Cheng;Dai-Zheng Liao;Zong-Hui Jiang
European Journal of Inorganic Chemistry 2004 Volume 2004(Issue 10) pp:
Publication Date(Web):1 APR 2004
DOI:10.1002/ejic.200300678
Two novel heterobimetallic supramolecular polymers, [CuAg4(CN)6(tacn)]n (1) and [CuAu2(CN)4(tacn)]n (2) (tacn = 1,4,7-triazacyclononane), have been synthesised from the building block [Cu(tacn)]2+, together with [Ag(CN)2]− (for 1) and [Au(CN)2]− (for 2). The large difference in structural type between 1 and 2 is probably due to the fact that the AgI centre is three-coordinate and trigonal whereas the AuI centre is linear. Metal−metal interactions play an important role in the formation of the supramolecular framework of 1 and the novel topology of 2. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Co-reporter:He-Dong Bian;Qing Yu;Hong Liang;Dai-Zheng Liao;Peng Cheng;Zong-Hui Jiang
Applied Organometallic Chemistry 2004 Volume 18(Issue 8) pp:
Publication Date(Web):10 AUG 2004
DOI:10.1002/aoc.677
The zinc(II) atom in the centrosymmetric complex is in a distorted N6 octahedral geometry defined by two tridentate ligands. Copyright © 2004 John Wiley & Sons, Ltd.
Co-reporter:Yingying Kou, Jinlei Tian, Dongdong Li, Wen Gu, Xin Liu, Shiping Yan, Daizheng Liao and Peng Cheng
Dalton Transactions 2009(Issue 13) pp:NaN2382-2382
Publication Date(Web):2009/02/09
DOI:10.1039/B819052F
Five binuclear Schiff base copper(II) complexes [Cu2(L)(OAc)]·3DMF (1), [Cu2(L)(OAc)]2·3DMF (2), [Cu2(L)(BNPP)]·3CH3CN (3), [Cu2(L)(Fa)]·2DMF (4) and [Cu2(L)(Pa)]·DMF (5) (H3L = N,N′-bis(3,5-tert-butylsalicylidene-2-hydroxy)-1,3-propanediamine, OAc = acetic acid, BNPP = bis(4-nitrophenyl)phosphate, Fa = 2-tetrahydrofuroic acid, Pa = benzoic acid) have been synthesized and characterized by X-ray single-crystal structure analysis. Variable-temperature magnetic susceptibility studies (2–300 K) indicate the existence of ferromagnetic coupling between the copper(II) ions in complexes 1 and 4, and antiferromagnetic coupling in complexes 3 and 5. The interaction of these complexes with CT-DNA has been studied by using absorption and emission spectral methods. The apparent binding constant (Kapp) values for complexes 1, 3, 4 and 5 are 4.67 × 105, 9.48 × 105, 4.30 × 105 and 3.90 × 105 M−1, respectively, which show that the complexes bind to DNA by moderate intercalative binding modes. Furthermore, all these complexes can cleave plasmid DNA to nicked DNA in a sequential manner as the concentrations or reaction times are increased in the absence of reducing agent. Their cleavage activities are promoted in the presence of hydrogen peroxide. The cleavage mechanisms between the complexes and plasmid DNA are likely to involve singlet oxygen 1O2 and ˙OH as reactive oxygen species.
Co-reporter:Jing Qian, Wen Gu, Hui Liu, Fengxian Gao, Li Feng, Shiping Yan, Daizheng Liao and Peng Cheng
Dalton Transactions 2007(Issue 10) pp:NaN1066-1066
Publication Date(Web):2007/02/07
DOI:10.1039/B615148E
Two novel binuclear complexes [Cu2(L)]·(ClO4)2 (1) and [Zn2(L)]·(ClO4)2 (2) were synthesized and crystallographically characterized {L = 14,54-dimethyl-12,52-dihydroxy-1(1,3),5(1,3)-dibenzene-3(1,4),7(1,4)-di-1,4,7-triazacyclononane}. The cation [Cu2(L)]2+ structure of 1 is similar to that of [Zn2(L)]2+ of 2. The central ion is bridged by the di-phenoxo of L and lies in a close to perfect square pyramidal geometry. 1 and 2 crystallize in the triclinic space group P. The two complexes effectively promote the cleavage of plasmid DNA in the presence of activating agents at physiological pH and temperature. The pseudo-Michaelis–Menten kinetic parameters kcat = 1.61 h−1, Km = 1.35 × 10−5 M for complex 1 in the presence of mercaptoethanol; kcat = 2.48 h−1, Km = 5.5 × 10−5M for complex 2 in the presence of hydrogen peroxide were obtained. The mechanism of plasmid DNA cleavage was studied by adding standard radical scavengers. DNA cleavage reaction by the binuclear Zn(II)/H2O2 system is a hydrolytic mechanism.
Co-reporter:Jing Qian, Shasha Yu, Wenjun Wang, Liping Wang, Jinlei Tian and Shiping Yan
Dalton Transactions 2014 - vol. 43(Issue 6) pp:NaN2655-2655
Publication Date(Web):2013/11/05
DOI:10.1039/C3DT51904J
A water-soluble MnIV 1,4,7-triazacyclononane complex, [MnIV2L2(μ-O)2](ClO4)2·2H2O (1), was prepared to serve as a nuclease mimic (L = 1,4,7-triazacyclononane-N-acetate). Complex 1 was readily synthesized from the highly water soluble ligand (L), with MnIII salt, [Mn3O(MeCO2)7]·3H2O in basic condition, and characterized by X-ray, IR, electronic spectroscopy, cyclic voltammetry and magnetic susceptibility as well as ESI-MS. The bond valence sum (BVS) analysis and magnetic data suggest that 1 is a MnIV–μ-O2–MnIV species. The electrospray mass spectrum and electronic spectrum of 1 in aqueous solution indicates that dinuclear Mn complex [MnIIIMnIVL2(μ-O)2]+ (2) is the active species. A predominantly hydrolytic cleavage mechanism was confirmed through experiments performed in the presence of various radical scavengers, T4 ligase and under anaerobic conditions. The kinetic aspects of DNA cleavage under pseudo- or true-Michaelis–Menten conditions were also detailed, kinetic parameters (kcat, KM, Vmax) were calculated to be 6.27 h−1, 7.35 × 10−5 M, 4.6 × 10−4 M h−1; 0.683 h−1, 1.93 × 10−5 M, 1.32 × 10−5 M h−1 for 2, respectively.
Co-reporter:Jing-Yuan Xu, Hai-Bin Song, Gong-Feng Xu, Xin Qiao, Shi-Ping Yan, Dai-Zheng Liao, Yves Journaux and Joan Cano
Chemical Communications 2012 - vol. 48(Issue 7) pp:NaN1017-1017
Publication Date(Web):2011/11/21
DOI:10.1039/C1CC16243H
An enneanuclear nickel(II) complex with a rectangular face-centered trigonal prism structure bridged by μ2-pyrazolate, μ6-CO32− and μ3-OH−groups was synthesized. It displays cluster glass-like magnetic behavior assigned to the single molecule magnet properties of {Ni9} clusters and weak intercluster interaction.
Co-reporter:Jing-Yuan Xu, Xin Qiao, Hai-Bin Song, Shi-Ping Yan, Dai-Zheng Liao, Song Gao, Yves Journaux and Joan Cano
Chemical Communications 2008(Issue 47) pp:NaN6416-6416
Publication Date(Web):2008/11/07
DOI:10.1039/B813705F
A novel octanuclear hydroxonickel(II) complex possessing a unprecedented cube molecular structure with eight Ni(II) ions at each vertex, six µ4-OH−groups closing each face and twelve exo-bidentate pyrazolate ligands (µ2-pz) spanning each edge, has been synthesized and its magnetic properties investigated.
Co-reporter:Dongdong Li, Jinlei Tian, Yingying Kou, Fuping Huang, Gongjun Chen, Wen Gu, Xin Liu, Daizheng Liao, Peng Cheng and Shiping Yan
Dalton Transactions 2009(Issue 18) pp:NaN3583-3583
Publication Date(Web):2009/03/18
DOI:10.1039/B823472H
Four new copper(II) complexes, [Cu(1,4-tpbd)Br2] (1), [Cu2(1,4-tpbd)(H2O)4](ClO4)4 (2), [Cu2(1,4-tpbd)(1,10-phen)2(DMF)2](ClO4)4 (3) and [Cu2(1,4-tpbd)(2,2′-bpy)2(ClO4)2](ClO4)2 (4), [1,4-tpbd = N,N,N′,N′-tetrakis(2-pyridylmethyl)benzene-1,4-diamine], have been synthesized to serve as artificial nucleases. Single crystal X-ray diffraction reveals that the copper(II) atom has a distorted intermediate between square pyramidal and trigonal bipyramidal configuration for 1 and a distorted square pyramidal geometry for 2, while a distorted octahedral environment for 3 and 4. Variable-temperature magnetic susceptibility studies (2–300 K) indicate the existence of antiferromagnetic coupling between the copper(II) ions in complex 2. The interactions of the four complexes with calf thymus DNA (CT-DNA) have been investigated by UV absorption, fluorescent spectroscopy and cyclic voltammetry, and the modes of CT-DNA binding for the complexes have been proposed. In the absence of external agents, supercoiled plasmid DNA cleavage by the complexes was performed under aerobic conditions, the influence on the DNA cleavage process of different complex concentrations, reaction times was also studied. The DNA cleavage mechanisms were demonstrated with radical scavengers and anaerobic conditions, indicating all complexes cleaved pBR322 DNA in 50 mM Tris-HCl/18 mM NaCl buffer (pH = 7.2) at 37 °C through a hydrolytic process. In the four copper(II) complexes, complex 2 showed highest cleavage activity with the pseudo-Michaelis–Menten kinetic parameters kcat = 4.23 h−1 and Km = 2.4 × 10−5 M.
Co-reporter:Hui Liu, Jinlei Tian, Yingying Kou, Jingyan Zhang, Li Feng, Dongdong Li, Wen Gu, Xin Liu, Daizheng Liao, Peng Cheng, Joan Ribas and Shiping Yan
Dalton Transactions 2009(Issue 47) pp:NaN10517-10517
Publication Date(Web):2009/10/19
DOI:10.1039/B904553H
This paper reports the synthesis, crystal structures, and magnetic properties of a series of mixed-valence polynuclear manganese complexes bridged by a dianionic 1,2,4-triazole-based ligand L2− (H2L = 3-(2-phenol)-5-(pyridin-2-yl)-1,2,4-triazole). Complexes 1 to 3 show a similar binuclear structure, with the central core of [MnIIMnIII(L)2] and some other small molecules also coordinated to the two Mn centers. The two [MnIIMnIII(L)2] subunits can be further connected by different dicarboxylic acids to construct non-charged tetranuclear complexes 4 to 7. In these complexes, each deprotonated dianionic ligand L2− acts as a μ2-bridged ligand to coordinate two Mn centers via the 1,2,4-triazole ring. Bond valence sum (BVS) calculations and Mn surrounding bond lengths indicate that the Mn center coordinated to the pyridine N atoms in the +2 oxidation state, while another Mn center coordinated to the phenolic O atoms is in the +3 oxidation state. The MnIII centre shows Jahn–Teller elongation along one of the axes. Magnetic studies show the presence of ferromagnetic MnIII–MnII coupling in the binuclear (1–3) and tetranuclear (4–7) complexes with the magnetic coupling constant (J) ranging from 0.58 to 1.17 cm−1, based on the Hamiltonian H = −2JS1·S2 (S1 = 5/2 and S2 = 2). In all cases both z′J′ (intermolecular interactions) and D parameter (Zero Field Splitting of the Mn (III) ion) has been introduced to improve the corresponding fit. The relationship of the coupling interaction between the MnII/MnIII and their electronic structures is discussed.
Co-reporter:Gong-Jun Chen, Xin Qiao, Jin-Lei Tian, Jing-Yuan Xu, Wen Gu, Xin Liu and Shi-Ping Yan
Dalton Transactions 2010 - vol. 39(Issue 44) pp:NaN10643-10643
Publication Date(Web):2010/10/04
DOI:10.1039/C0DT00718H
Two Eu(III) complexes, [Eu(acac)3(dpq)] (1) and [Eu(acac)3(dppz)] CH3OH (2) {viz. acetylacetonate (acac), dipyrido[3,2-d:20,30-f]quinoxaline (dpq), dipyrido[3,2-a:20,30-c] phenazine (dppz)}, have been synthesized and their DNA binding, photo-induced DNA cleavage activity and cell cytotoxicity are studied. The complexes display significant binding propensity to the calf thymus DNA in the order: 2(dppz) >1(dpq). Cleavage experiments using pBR322 supercoiled DNA suggest major groove binding for 2 and minor groove binding for 1. The mechanistic aspects on natural light (natural light in room during the day) and UV-A (365 nm) irradiation are via a mechanistic pathway involving formation of singlet oxygen and hydroxyl radical as the reactive species. The photo-induced DNA cleavage activity of 2 is also stronger than 1. The cytotoxicity of 1 and 2 against HeLa (cervical) cancer cells show that the IC50 value of 19.11 ± 3.56 μM and 17.95 ± 5.47 μM, respectively.
Co-reporter:Jing Qian, Jinlei Tian, Wen Gu, Song Gao, Liu Xin, Shiping Yan, Joan Ribas, Daizheng Liao and Peng Cheng
Dalton Transactions 2008(Issue 48) pp:NaN6952-6952
Publication Date(Web):2008/10/18
DOI:10.1039/B808916G
A new FeIII6cluster, [Fe3L2(ida)(μ-OH)3(μ-O)]2·4ClO4·2CH3OH·8H2O (1) (where L = N-methyl-N,N-bis(2-pyridylmethyl)amine; H2ida = iminodiacetic acid), has been synthesized and magnetic properties are shown. The asymmetric unit of 1 contains a triangular [Fe3L2(ida)(μ-OH)3(μ-O)]2+ unit and two such trinuclear units are further connected by two ida2−, generating a hexanuclear FeIII core in 1. Variable temperature magnetic susceptibility studies reveal the presence of dominant antiferromagnetic exchange interactions and the variable-field and temperature magnetization measurements establish that each Fe3 cluster has S = 5/2 ground state and the coupling between the two moieties is almost zero.
Co-reporter:Gong-Jun Chen, Chun-Yan Gao, Jin-Lei Tian, Jinkui Tang, Wen Gu, Xin Liu, Shi-Ping Yan, Dai-Zheng Liao and Peng Cheng
Dalton Transactions 2011 - vol. 40(Issue 20) pp:NaN5583-5583
Publication Date(Web):2011/04/18
DOI:10.1039/C1DT10050E
By changing the ratio of reactants, two mononuclear Dy complexes, [Dy(phen)(acac)3] (1) and [Dy(phen)2(NO3)2(acac)]·H2O (2) have been synthesized and structurally characterized. In 1, a Dy atom bearing square-antiprism coordination geometry exhibits SMM behaviour, while compound 2 with a bicapped-square-antiprism geometry does not show such SMM properties. The different magnetic behaviours seen in 1 and 2 are probably due to a different coordination environment and ligand field around the Dy(III) ions. The results proved the important influence of the structural environment of a SMM on its magnetic behaviour.
Co-reporter:Chun-Yan Gao, Xin Qiao, Zhong-Ying Ma, Zhi-Gang Wang, Jing Lu, Jin-Lei Tian, Jing-Yuan Xu and Shi-Ping Yan
Dalton Transactions 2012 - vol. 41(Issue 39) pp:NaN12232-12232
Publication Date(Web):2012/07/30
DOI:10.1039/C2DT31306E
Three new zinc(II) complexes: [Zn2(L1)2Cl2](ClO4)2·C2H5OH (1) and [Zn2L2X4]·2CH3CN (X = Br for 2, Cl for 3), utilizing two new and interrelated di-nucleating polypyridyl ligands (L1, L2), have been synthesized and characterized by using various physico-chemical techniques. The interactions of three complexes with CT-DNA have been explored by using absorption, emission and CD spectral methods, which reveal that three complexes bind to CT-DNA by partial intercalation binding modes. Notably, in the presence of H2O2 as a revulsant or an activator, the cleavage abilities of all complexes are obviously enhanced. The hydrolytic mechanism was demonstrated by adding standard radical scavengers and anaerobic reaction. Further, the protein binding ability has been monitored by quenching of tryptophan emission in the presence of complexes using BSA as a model protein. The quenching mechanisms of BSA by the complexes are static procedures. In addition, the in vitro cytotoxicity of the complexes on three human tumor cells lines (HeLa, MCF-7 and RL952) and the apoptosis-inducing activity of 3 were assessed by MTT, Clonogenic assay, Hoechst 33342 staining, Cell cycle and Annexin V binding experiments.
![2-Propanol, 1,3-bis[bis(2-quinolinylmethyl)amino]-](http://img.cochemist.com/ccimg/868700/868668-01-3.png)
![2-Propanol, 1,3-bis[bis(2-quinolinylmethyl)amino]-](http://img.cochemist.com/ccimg/868700/868668-01-3_b.png)
![PHENOL, 2-[[[(1R)-1-(1-NAPHTHALENYL)ETHYL]IMINO]METHYL]-](http://img.cochemist.com/ccimg/827400/827306-39-8.png)
![PHENOL, 2-[[[(1R)-1-(1-NAPHTHALENYL)ETHYL]IMINO]METHYL]-](http://img.cochemist.com/ccimg/827400/827306-39-8_b.png)
![Dipyrido[3,2-a:2',3'-c]phenazine](/data/chemimg/1778900/19535-47-8.png)
![Dipyrido[3,2-a:2',3'-c]phenazine](/data/chemimg/1778900/19535-47-8_b.png)