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Graphical abstract Novel Di-and tetranuclear copper(II) complexes have been synthesized and structurally characterized. The interaction with DNA of two complexes in non-intercalation binding mode was confirmed by spectroscopic studies and molecular docking. The two compounds show cytotoxicity against HeLa cells and AGZY-83a cell lines via an apoptotic cell death mechanism. Highlights • Di-and tetranuclear copper(II) complexes have been synthesized. • The metal complexes bind to FS-DNA in non-intercalation binding mode. • Both complexes show in vitro cytotoxicity via an apoptotic cell death mechanism. Abstract New di-and tetranuclear copper(II) complexes of formula [Cu (phen) (mqpa)]·2H 2 O·CH 3 CH 2 OH (1) and [Cu 2 (phen) 2 (ppa) 2 (H 2 O) 2 ]·4H 2 O·CH 3 CH 2 OH (2) (phen = 1,10- phenanthroline, H 2 mqpa = 4-(2-methyl-quinolin-1-ium-8-yloxy) phthalic acid, H 2 ppa = 3-(pyridiium-3-yloxy) phthalic acid) have been synthesized and characterized by elemental analysis, infrared spectrum, and single X-ray diffraction. In complex 1 , two [Cu(phen)] units are bridged by two mqpa ligands via carboxyl bridges, forming a binuclear compound with Cu…Cu distance of 3.329 Å. Through strong π…π and CH…π weak interaction, complex 1 molecules are assembled into 2D supramolecular structures. Compound 2 features a metallamacrocyclic assembly in which four [Cu(phen)(H 2 O)] species are linked together by four ppa bridge ligands in head to tail fashion with Cu…Cu distance of 8.713 and 8.528 Å. The adjacent tetranuclear complex 2 molecules stacked together through strong π…π. The Cu(II) ions in two compounds are all in square pyramidal geometry. The interaction of two complexes with FS-DNA was studied by electronic absorption titration and ethidium bromide displacement experiments, the result displayed both complexes interact with DNA in non-intercalation mode, molecular docking simulation displayed that complex 1 interacts with DNA with a partial intercalation mode and complex 2 favor binding to major groove. Both complexes exhibit cytotoxicity against HeLa cells and AGZY-83a cells, and complex 2 has similar anticancer activity toward HeLa cells with cisplatin. The results of apoptosis assays by flow cytometry shows complex 2 promotes more apoptosis in HeLa cell lines than complex 1. [ABSTRACT FROM AUTHOR]

A series of complexes [Pd(L1)(Phen)]·2H2O (1), [Pd(L2)(Phen)]·H2O (2), [Pd(L3)(Phen)]·H2O (3), [Pd(L4)(Phen)]·2H2O (4) and [Pd(L5)(Phen)]·2H2O (5) were prepared. The complexes were characterized by IR, 1H NMR, elemental analysis, and single-crystal X-ray diffractometry. The binding of the complexes was investigated by fluorescence spectrum and UV spectrum, showing the ability of interaction with DNA of intercalative mode. Gel electrophoresis assay demonstrated the ability of the complexes to cleave the pBR322 DNA. Moreover, the five complexes bind to DNA with different binding affinities, in ascending order: complex 1 < 2<3 < 4 < 5. Evaluation of cytotoxic activity of the complexes against five different cancer cell lines proved that the complexes exhibited cytotoxic specificity and significant cancer cell inhibitory rate. [ABSTRACT FROM AUTHOR]

Abstract: The complex [Cu4(phen)4(H2O)2]·(pyri)·3H2O(where phen = 1,10-phenanthroline and pyri = 3,5-pyridine dicarboxylic acid)has been synthesized and characterized. IR spectra, elemental analysis and X-ray single-crystal diffraction were carried out to determine the composition and crystal structure of the complex. The binding of the complex with HC-DNA (HeLa cells DNA, which was extracted by ourselves) was investigated by fluorescence spectrum. Gel electrophoresis assay demonstrates the ability of the complex to cleave the extracted HC-DNA. Additionally, the complex exhibited a significant cytotoxic specificity and cancer cell inhibitory rate. The apoptotic tests indicate that the complex have an apoptotic effect on HeLa cells. [Copyright &y& Elsevier]

Abstract: Two novel dinuclear complexes [Co2(L)2(phen)2·2H2O]n (1), [Co2(L)2(bipy)2]n (2) (where phen=1,10-phenanthroline, bipy=2,2′-bipyridine, and L=biphenyl-2,4′-dicarboxylic acid) have been synthesized and characterized using IR, 1H NMR, element analysis and single-crystal X-ray diffractometry. The binding of the complexes with HC-DNA (HeLa cells DNA, which was extracted by ourselves) was investigated by fluorescence spectrum. The experimental results show that the two complexes have the ability to bind with extracted HC-DNA. Gel electrophoresis assay demonstrates the ability of the complexes to cleave the extracted HC-DNA. The complexes exhibit a higher cytotoxicity against tumor cells as against normal cells in vitro. Further more, the apoptotic tests indicate that the complexes have an apoptotic effect on HeLa cells. [Copyright &y& Elsevier]

Abstract: In an attempt to establish fundamental structure–activity relationships (SAR) of Pt/Pd-based anti-tumour compounds, we have recently designed monodentate pyridyl amide ligand containing central amide units which possess external metal co-ordinating pyridyl group and internal amide functionality. It was prepared in one step from commercially available compounds in moderate to good yield. Surprisingly, treatment of K2[MCl4] [M=Pt(II), Pd(II)] with ligand N-(4-chlorophenyl)-3-pyridinecarboxamide (L) in the same reaction condition affords two different hydrogen-bonded polymers: cis-[PtL2Cl2]·CH3OH·DMF (1) and trans-[PdL2Cl2]·2DMF (2). Fluorescence analysis indicates that the two complexes can bind to fish sperm DNA (FS-DNA) and gel electrophoresis assay demonstrates the ability of the complexes to cleave the pBR322 plasmid DNA. The two complexes exhibit cytotoxic specificity and significant cancer cell inhibitory rate. Furthermore, cytotoxicity values are higher in the case of cis-Pt(II) complex than trans-Pd(II) complex in four different cancer cell lines. [ABSTRACT FROM AUTHOR]

Abstract: Four novel Zn(II) complexes [Zn(L1)(bipy)(H2O)2]·4H2O(1), [Zn(L1)(phen)(H2O)2]·4H2O(2), [Zn(L2)(bipy)(H2O)2]·4H2O(3) and [Zn(L2)(phen)(H2O)2]·4H2O (4), where bipy=2,2′-bipyridine, phen=1,10-phenanthroline, L1 =2,2′-bipyridine 5,5′-dicarboxylic acid, L2 =2,2′-bipyridine-4,4′-dicarboxylic acid, have been synthesized and characterized using IR, 1H NMR, element analysis and single-crystal X-ray diffractometry. The unit cell parameters for the title complex (1), a =7.9621(10)Å, b =12.6853(17)Å, c =13.3714(17)Å, α =68.549(2)°, β=79.065(2)°, γ =88.723(2)°, V =1232.5(3)Å3, Z =15, space group,P-1(2).complex (4) a =9.5710(5)Å, b =14.1140(7)Å, c =19.0045(9)Å, α =90°, β =99.9920(10)°, γ =90°, V =2528.3(2)Å3, Z =32, space group, P121/n 1(14). The binding of the complexes with fish sperm DNA (FS-DNA) was investigated by electronic absorption spectra and fluorescence spectroscopy, showing that the complexes have the ability of interaction with DNA of intercalative mode. The intrinsic binding constant K of the complexes with FS-DNA is 0.37×105 M−1 (1) 0.73×105 M−1 (2), 0.98×105 M−1 (3), and 1.05×105 M−1 (4). The results indicate that the four complexes bound to DNA with different binding affinity, in the order complex 4 > 3 > 2 > 1. Gel electrophoresis assay demonstrates the ability of the complexes to cleave the pBR322 plasmid DNA. The cytotoxic activity of the complexes was tested against four different cancer cell lines. The four complexes exhibited cytotoxic specificity and significant cancer cell inhibitory rate. [Copyright &y& Elsevier]

Abstract: A novel tetranuclear palladium(II) complex [Pd4(phen)4 (μ-pydc)4]·10H2O (phen = 1,10-phenanthroline, pydc = pyridine-3,4-dicarboxylate) has been synthesized and characterized. In the tetranuclear complex, two pairs of dipalladated [Pd(phen)] moieties are bridged together by four pydc, presenting a hairpin molecular shape. The binding of the title complex with fish sperm DNA (FS-DNA) has been investigated by UV spectrum and fluorescence spectrum. All the results indicate that the complex bind to DNA in an intercalative mode and considerating the molecular shape and size, the dipalladated phenanthroline moieties bisintercalate to the base pairs of DNA. Agarose gel electrophoresis assay demonstrates the ability of the complex to cleave the pBR322 plasmid DNA. Cytotoxic activity studies show the complex exhibited good cytotoxic activity against four different cancer cell lines. [Copyright &y& Elsevier]

Abstract: Two novel complexes, namely, [Pd(pdc)2]·(dmp)·6H2O (1) and [Pd(pdc)2K(H2O)5·3H2O]n (2) [H2pdc=pyridine-2,3-dicarboxylate acid, dmp=2,9-Dimethyl-1,10-phenanthroline] were synthesized and characterized as pH-dependent products. Gel electrophoresis assay demonstrated the ability of the complexes to cleave the pBR 322 plasmid DNA. Values of IC50 calculated for complexes 1 and 2 show that the two complexes exhibit good cytotoxic activity against different cell lines tested in general, especially more effective against HL-60 and A2780cisR cell lines. [Copyright &y& Elsevier]

Abstract: The complexes [Pt(dmphen)CO3]·H2O (1), [Pd(dmphen)CO3]·H2O (2) (dmphen is 2,9-dimethyl-1,10-phenanthroline) have been synthesized and characterized. The binding of the complexes with FS-DNA was investigated by UV spectrum and fluorescence spectrum, showing that the complexes have the ability of interaction with DNA of intercalative mode. The intrinsic binding constant K of the complexes with FS-DNA is 1.8×105 M−1 (1) and 1.6×104 M−1 (2), respectively. Gel electrophoresis assay demonstrated the ability of the complexes to cleave the pBR 322 plasmid DNA. Evaluation of cytotoxic activity of the complexes against four different cancer cell lines proved that the complexes exhibited cytotoxic specificity and significant cancer cell inhibitory rate. [Copyright &y& Elsevier]

Abstract: The novel Pd(II) complex, [Pd2(μ-bzta)4]·1.5DMSO (where bzta=benzothiazole-2-thiolate) has been synthesized and structurally characterized by element analysis, IR and single-crystal X-ray diffractometry. In the binuclear complex, two palladium(II) are bridged by four deprotonated benzothiazole-2-thialate in a head to tail disposition and the distance of the two Pd(II) is 2.747Å. Three-dimensional structure of the complex was constructed though S⋯S (3.339Å) weak interaction and π⋯π stack. The binding of the title complex with fish sperm DNA (FS-DNA) has been investigated by absorption and fluorescence spectra. The results indicate that the complex bind to FS-DNA in an intercalative mode and the intrinsic binding constant K of the title complex with FS-DNA is about 1.2×104 M−1. Gel electrophoresis assay demonstrates the ability of the complex to cleave the pUC19 plasmid DNA. [Copyright &y& Elsevier]

Abstract: The complex [Cd2(phen)4(p-phth)(H2O)2](p-phth)·10H2O (1) has been synthesized by the reaction Cd(NO3)2 with phen and p-phth (where phen=1,10-phenanthroline, p-phth= p-phthalic acid) in a solution of ethanol and distilled water. The crystal structure was characterized by X-ray single-crystal diffraction and infrared spectrum. In 1, a novel 2D supramolecular structure was formed, containing water octamer and tetramer. [Copyright &y& Elsevier]

Two new complexes, Zn(L) 2 (H 2 O) 2 ( 1 ) and Mn(L) 2 (H 2 O) 2 ( 2 ) [L = 2-Methyl-1H-4,5-imidazoledicarboxylic acid] were synthesized and characterized by elemental analysis, infrared spectroscopy, and single crystal X-ray diffraction. Intramolecular weak interactions, such as hydrogen-bond and intermolecular interactions were presented in the complexes. The activities of the complexes binding with DNA, and cytotoxic activities were studied. The binding of complexes with fish sperm DNA (FS-DNA) was investigated by fluorescence spectra. Gel electrophoresis assay demonstrated the ability of the complexes to cleave the pBR322 plasmid DNA. The cytotoxic activities of the complexes were tested against the KB cell line. Cytotoxic activity studies showed the two complexes exhibited significant cancer cell inhibitory rate. The most active compound was complex 1 with IC 50 and CC 50 value of 36.5, 429, with the selectivity index (SI = 11.75) among the tested compounds. [ABSTRACT FROM AUTHOR]

Hydrothermal reaction of rare earth oxides with 1H-benzimidazole-5,6-dicarboxylic acid (H 3 bidc) and MnSO 4 ·H 2 O afforded a series of new three-dimensional (3D) coordination polymers, namely, [Ln 2 Mn(Hbidc) 2 (SO 4 ) 2 ·8H 2 O] n (Ln = Sm ( 1 ), Eu ( 2 ), Tb ( 3 ), Dy ( 4 ) and Ho ( 5 )) and [Gd 2 Mn(Hbidc) 2 (SO 4 ) 2 ·7H 2 O] n ( 6 ). Their structures have been determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, FT-IR, powder X-ray diffraction and thermogravimetric analyses (TGA). The single-crystal X-ray diffraction analysis reveals that coordination polymers 1 – 6 have similar 3D frameworks fabricated through Hbidc 2 − and SO 4 2 − bridging dinuclear lanthanide secondary building units. Moreover, the photoluminescence of complexes 1 – 4 and magnetism of complexes 4 and 6 have been investigated, 4 exhibits remarkably slow magnetic relaxation behavior with the energy barrier Δ E / k B = 83.3 K. [ABSTRACT FROM AUTHOR]

Abstract: Heterometallic coordination polymers of the form {[SmMn2(imdc)2(OAc)(H2O)]·2H2O} n (1) (H3imdc=4,5-imidazoledicarboxylic acid, HOAc=acetic acid) were hydrothermally synthesized and characterized by elemental analysis, IR, and single-crystal X-ray diffraction. The results reveal that 1 has a three-dimensional framework containing Sm2Mn4 clusters. The luminescence and magnetic properties of 1 were also investigated. [Copyright &y& Elsevier]