Synthesis,characterization, and antitumor properties of ruthenium(II) anthraquinone complexes

Three new Ru(II) complexes, [Ru(dmb)₂(ipad)](ClO₄)₂ (dmb = 4,4′-dimethyl-2,2′-bipyridine, ipad = 2-(anthracene-9,10-dione-2-yl) imidazo[4,5-f][1,10]phenanthroline, 1), [Ru(dmp)₂(ipad)](ClO₄)₂ (dmp = 2,9-dimethyl-1,10-phenanthroline, 2), and [Ru(dip)₂(ipad)](ClO₄)₂ (dip = 4,7-diphenyl-1,10-phenanthroline, 3), have been synthesized and characterized. The three Ru(II) complexes intercalate with the base pairs of DNA. The in vitro antiproliferative activities and apoptosis-inducing characteristics of these complexes were investigated. The complexes exhibited cytotoxicity against various human cancer cell lines. BEL-7402 cells displayed the highest sensitivity to 1, accounted for by the greatest cellular uptake. Complex 1 was shown to accumulate preferentially in the nuclei of BEL-7402 cells and cause DNA damage and induce apoptosis, which involved cell cycle arrest and reactive oxygen species generation.     

Synthesis of transition metal complexes containing a Schiff base ligand derived from 1,10-phenanthroline-2,9-dicarboxaldehyde and 2-aminobenzenethiol

The synthesis of a new Schiff base containing 1,10-phenanthroline-2,9-dicarboxaldehyde and 2-aminobenzenethiol subunits is described. The reaction of 1,10-phenanthroline-2,9-dicarboxaldehyde with 2-aminobenzenethiol leads to the isolation of 2,9-bis(2-benzothiazolinyl)-1,10-phenanthroline (I) which undergoes rearrangement when reacted with cobalt, nickel, copper or zinc ions to produce complexes of the tautomeric Schiff base 2,9-bis[2-(2-mercaptophenyl)-2-azaethene]-1,10-phenanthroline (L). The [Cu(L)ClO₄][ClO₄] and [M(L)X₂] complexes (where M = Co(II), Ni(II) and Zn(II) and X = Br) were characterized by physical and spectroscopic measurements which indicated that the ligand is acting probably as a tetradentate N₄ chelating agent.     

Ruthenium(II) complexes containing 2,9-dimethyl-1,10-phenanthroline and 4,4′-dimethyl-2,2′-bipyridine as ancillary ligands: synthesis,characterization and DNA-binding

Two new Ruthenium (II) polypyridyl complexes [Ru(dmp)₂(ipbp)](ClO₄)₂ (1) (dmp = 2,9-dimethyl-1,10-phenanthroline, ipbp = 3-(1H-imidazo[4,5-f][1,10]phenanthrolin-2-yl)-4H-1-banzopyran-2-one) and [Ru(dmb)₂(ipbp)](ClO₄)₂ (2) (dmb = 4,4′-dimethyl-2,2′-bipyridine) have been synthesized and characterized by elemental analysis, FAB-MS, ES-MS and ¹H NMR and cyclic voltammetric methods. The DNA-binding behaviors of these complexes were investigated by spectroscopic titration, viscosity measurements, and thermal denaturation. Absorption titration and thermal denaturation studies reveal that these complexes are moderately strong binders of calf thymus DNA (CT-DNA). Viscosity measurements show that the complexes 1 and 2 interact with CT-DNA by intercalative mode. The DNA-binding affinity of the complex 2 is larger than that of complex 1.     

Effect of the ancillary ligands on the binding of ruthenium(II) complexes [Ru(dmp)2(MCMIP)]2+ and [Ru(dmb)2(MCMIP)]2+ with DNA

Two polypyridine ruthenium(II) complexes, [Ru(dmp)₂(MCMIP)]²⁺ (1) (MCMIP = 2-(6-methyl-3-chromonyl)imidazo[4,5-f][1,10]-phenanthroline, dmp = 2,9-dimethyl-1,10-phenanthroline) and [Ru(dmb)₂(MCMIP)]²⁺ (2) (dmb = 4,4′-dimethyl-2,2′-bipyridine), have been synthesized and characterized by elemental analysis, ES-MS and ¹H NMR. The DNA-binding behaviors of these complexes were investigated by electronic absorption titration, fluorescence spectroscopy, viscosity measurements and thermal denaturation. The results show that 1 and 2 effectively bind to CT-DNA; the DNA-binding affinities are closely related to the ancillary ligand.     

Effect of heterocyclic diimine ligands with donor and acceptor substituents on the spectroscopic and electrochemical properties of Au(III) complexes

The composition, structure, and properties of a series of Au(III) complexes with heterocyclic diimine ligands [Au(N^N)Cl₂]⁺, where (N^N) = 2,2′-bipyridine (Bipy), 4,4′-dimethyl-2,2′-bipyridine (DmBipy), 2,2′-biquinoline (Bqx), 1,10-phenanthroline (Phen), 2,9-dimethyl-1,10-phenanthroline (DmPhen), and 4,7-diphenyl-1,10-phenanthroline (DphPhen), were characterized by ¹H NMR, electronic absorption, and emission spectroscopy and also by cyclic voltammetry. The influence of donor and acceptor substituents on the spectroscopic and electrochemical properties of the Au(III) complexes was revealed.     

Synthesis and characterization of manganese(II), nickel(II), copper(II) and zinc(II) Schiff-base complexes derived from 1,10-phenanthroline-2,9-dicarboxaldehyde and 2-mercaptoethylamine

The synthesis of a new Schiff base containing 1,10-phenanthroline-2,9-dicarboxaldehyde and 2-mercaptoethylamine is described. The reaction of 1,10-phenanthroline-2,9-dicarboxaldehyde with 2-mercaptoethylamine leads to 2,9-bis(2-ethanthiazolinyl)-1,10-phenanthroline (I) which undergoes rearrangement when reacted with manganese, nickel, copper or zinc ions to produce complexes of the tautomeric Schiff base 2,9-bis[2-(2-mercaptoethyl)-2-azaethene]-1,10-phenanthroline (L). The [M(L)Cl₂] complexes [where M = Mn(II), Ni(II), Cu(II) and Zn(II) ions] were characterized by physical and spectroscopic measurements which indicated that the ligand is a tetradentate N₄ chelating agent.     

Synthesis and crystal structures of ruthenium(II) complexes with polypyridyl: [Ru(bpy)2(AFO)](ClO4)2 · H2O and [Ru(dmp)2 (AFO)](ClO4)2 · 1/2DMF · 1/2MeCN

Two ruthenium(II) complexes with polypyridyl ligands, [Ru(bpy)₂(AFO)](ClO₄)₂ · H₂O (1) and [Ru(dmp)₂ (AFO)](ClO₄)₂ · 1/2DMF · 1/2MeCN (2) (bpy = 2,2′-bipyridine; dmp = 2,9-dimethyl-1,10-phenanthroline; AFO = 4,5-diazafluoren-9-one; DMF = N,N-dimethylformamide), were synthesized and characterized by elemental analyses, i.r. and u.v.-vis. spectra. The structures of the two complexes were determined by single crystal X-ray diffraction techniques. To relieve ligand interaction, the coordination sphere is distorted so as to form specific angles (δ) between the polypyridyl ligand planes and coordination planes (N-Ru-N). This revised version was published online in June 2006 with corrections to the Cover Date.     

DNA-binding and cleavage activity of polypyridyl ruthenium(II) complexes

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

Allyl rhodium(III) complexes containing heterocyclic nitrogen ligands

Summary A series of hexacoordinated Rh^III complexes of general formula trans-[RhCl₂(allyl)(N-N)] (allyl = C₃H₅ or C₄H₇; N- = 1,10-phenanthroline, 2,9-dimethyl-1,10-phenanthroline, 4,7-diphenyl-1,10-phenanthroline, 2,2-bipyridine or 4,4-dimethyl-2,2-bipyridine) have been synthesized and characterized by spectroscopic methods. The complexes have an octahedral geometry with the Cl ligands coordinated in the trans positions. The catalytic activity of [RhCl₂(C₄H₇)(phen)] with respect to hydrogenation of alkenes has been investigated.     

Synthesis,characterization, DNA binding studies and in vitro cytotoxicity of platinum(II)-dihalogenido complexes containing bidentate chelating N-donor ligands

Platinum(II) complexes, [Pt(L_x)X₂] (1–6), where X = Br or I and L_x = 2,2′-bipyridine or 1,10-phenanthroline derivatives (5,5′-dimethyl-2,2′-bipyridine (5-Mebpy), 4,4′-dimethyl-2,2′-bipyridine (4-Mebpy), and 5-amino-1,10-phenanthroline (5-NH₂phen)) were prepared. The complexes were characterized by the elemental analysis, mass spectrometry, infrared, and multinuclear (¹H, ¹³C and ¹⁹⁵Pt) 1-D and 2-D NMR spectroscopies, and by single-crystal X-ray analysis of [Pt(4-Mebpy)I₂] (4). All the platinum(II) complexes (1–6) were evaluated for in vitro cytotoxicity against human cancer cell lines A2780 and A2780R, and against non-malignant MRC5 cell line. All the complexes were nontoxic up to the 50 μM concentration, although they were found to readily bind to calf-thymus DNA (CT-DNA), as determined by spectrophotometric titration (K_b ≈ 10⁷ M^?1) and ethidium bromide displacement assay.     

Bimetallic bis(diphenylphosphino)acetylene bridged copper(I) complexes with 1,10-phenanthroline derivatives: synthesis,crystal structure,and spectroscopic characterization

A new series of bimetallic bis(diphenylphosphino)acetylene-bridged copper(I) 1,10-phenanthroline complexes, [Cu₂(dppa)₂(L)₂](BF₄)₂; L?=?1,10-phenanthroline (1); 4-methyl-1,10-phenanthroline (2); 4,7-dimethyl-1,10-phenanthroline (3); and 2,9-dimethyl-1,10-phenanthroline (4), have been prepared and characterized by spectroscopic methods. The X-ray structures of 1 and 4 were determined. The structures consist of centrosymmetric bimetallic 10-membered chair-like dimetallacycles. In 1, intermolecular C–H?π interactions result in bending of the phenanthroline ligand and sterically induced lengthening of one Cu–P bond. In 1–4, the ³¹P NMR downfield coordination shift, relative to the free ligand, correlates with the basic strength of the 1,10-phenanthroline ligands.     

对苯二甲酸根桥联的双核铬(Ⅲ)配合物的合成与磁性

以对苯二甲酸根(TPHA)为桥联配体.分别端接4.4＇-二甲基-2.2＇-联吡啶(Me 2bpy),2.9-二甲基-1.10-邻菲哕啉(Me2phen)和5-氯-1,10-邻菲哕啉(Cl-phen).合成了3种新的双核铬(Ⅲ)配合物[Cr2-(TPHA)(Me2bpy)4](NO3)4(1),[Cr2(TPHA)(Me2phen)4](NO3)4(2)和[Cr 2(TPHA)(Clphen)4](N)3)4(3).经元素分析、摩尔电导和磁性测定以及红外光谱和电子光谱等手段,推定这些配合物具有TPHA桥联双核铬(Ⅲ)结构,其中,每个铬(Ⅲ)离子处于畸变八面体配位环境.测定了配合物(1)的变温磁化率(4～300 K),其数值用最小二乘法和从自旋Hamiltonian算符(H=-2JS^1S^2)导出的磁方程拟合,求得交换积分为-2.98 cm-1,结果表明双核配合物中金属离子间存在弱的反铁磁自旋交换作用.     

Rhodium and platinum complexes as catalysts for the polymerization of phenylacetylene

In polymerization reactions of phenylacetylene three different types of polyphenylacetylene (PPA) were prepared by using Rh and Pt complexes as catalysts in different reaction conditions. Type I PPA is obtained with [Rh (COD) Chel] PF₆ complexes (COD = cis,cis-cycloocta 1,5-diene; chel = 2,2′-bipyridine, 1,10-phenanthroline, 2,9-dimethyl-1,10-phenanthroline, 5,6-dimethyl-1,10-phenanthroline, 3,4,7,8-tetramethyl-1,10-phenanthroline) in bulk, benzene methanol, while type II PPA is obtained with the same catalysts in p-dioxane and type III PPA in the presence of [Pt (? C?CPh)₂(PPh₃)₂] in bulk. Type I, II, and III PPA exhibit different IR and ¹H-NMR spectra, which have been compared with literature data. Correlations proposed by different Authors between spectral properties of PPA and chain structures are also discussed.     

Five new cobalt(II) complexes based on indazole derivatives: synthesis,DNA binding and molecular docking study

Five cobalt(II) complexes based on 1H-indazole-3-carboxylic acid (H₂L), [Co(phen)(HL)₂]·2H₂O (1), [Co(5,5′-dimethyl-2,2′-bipy)(HL)₂] (2), [Co(2,2′-bipy)₂(HL)₂]·5H₂O (3), [Co₂(2,9-dimethyl-1,10-phen)₂(L)₂] (4) and [Co₂(6,6′-dimethyl-2,2′-bipy)₂(L)₂]·H₂O (5) (2,2'-bipy = 2,2′-bipyridine, phen = 1,10-phenanthroline), have been synthesized and structurally characterized by elemental analyses, IR and UV-vis spectroscopies and single-crystal X-ray crystallography. The results indicate that 1–3 possess mononuclear Co(II) structures, while 4 and 5 exhibit binuclear structure. 1D water tape which is linked by the multiple hydrogen bonds was embedded in the 3D motif of complex 3. Complexes 4 and 5 show two orthogonal planes of motif that was constituted by phen/2,2′-bipy and indazole acid, respectively. The intermolecular interactions including hydrogen bonding and π-π stacking interactions are stabilizing these complexes. The interactions of the synthesized complexes with calf-thymus DNA (CT-DNA) have been investigated by UV-vis absorption titration, ethidium bromide displacement assay and viscosity measurements. The results reveal that the complexes could interact with CT-DNA via a groove binding mode. Their behavior rationalization was further theoretically studied by molecular docking.     

Supramolecular frameworks composed of copper(II), zinc(II), and ferrous(II) complexes having 3-bromo or 3,8-dibromo-1,10-phenanthroline ligand with different molar ratios of metal and ligand

Abstract  

Three copper(II), one zinc(II), and one ferrous(II) complexes having 3-bromo or 3,8-dibromo-1,10-phenanthroline ligand with different metal/ligand molar ratios, formulated as [Cu(3-bromo-phen)(ClO₄)(C₃H₇NO)₂(H₂O)](ClO₄) (1), [Cu(3,8-dibromo-phen)(ClO₄)(C₃H₇NO)₂(H₂O)](ClO₄) (2), [Cu(3,8-dibromo-phen)(ClO₄)(H₂O)₃](ClO₄)(H₂O)₃ (3), [Zn(3,8-dibromo-phen)₂(H₂O)₂](ClO₄)₂(H₂O)₂ (4), and [Fe(3,8-dibromo-phen)₃](ClO₄)₂(H₂O)(CH₄O)(C₃H₆O)₂ (5) (phen = 1,10-phenanthroline), have been synthesized and characterized in this paper. X-ray single-crystal diffraction studies reveal the different crystallographic symmetry and packing fashions between neighboring phen rings in 1:1 Cu(II) complexes 1–3 due to the alteration of bromo substituent 1,10-phenanthroline ligands and coordinated or free solvent molecules. Additionally, in 1:2 Zn(II) and 1:3 Fe(II) complexes 4 and 5, continuous π–π stacking and alternating π–π and dimeric p–π stacking are found.     

Synthesis and magnetic properties of chloroanilato-bridged manganese(II) binuclear complexes

Five chloroanilato-bridged manganese(II) binuclear complexes, [Mn₂(CA)L₄](ClO₄)₂, where L = 4,4′-dimethyl-2,2′-bipyridine (Me₂-bpy), 5-methyl-1,10-phenanthroline (Me-phen), 5-chloro-1,10-phenanthroline (Cl-phen), 5-nitro-1,10-phenanthroline (NO₂-phen) and 2,9-dimethyl-1,10-phenanthroline (Me₂-phen), and CA represents the dianion of chloroanilic acid, have been synthesized and characterized by elemental analyses, molar conductivity and room temperature magnetic moment measurements, and by spectroscopy. It is proposed that these complexes have CA-bridged structures and consist of two manganese(II) ions in a distorted-octahedral environment. The complexes [Mn₂(CA)(Me₂-bpy)₄](ClO₄)₂ (1) and [Mn₂(CA)(Me-phen)₄](ClO₄)₂ (2) were characterized by variable temperature magnetic susceptibility measurements (4–300 K) and the observed data were successfully simulated by an equation based on the spin Hamiltonian operator, Ĥ = −2JŜ ₁ Ŝ ₂, giving the exchange integral J = −1.98 cm⁻¹ for (1) and J = −2.41 cm⁻¹ for (2). This result indicates that there is a weak antiferromagnetic spin-exchange interaction between the two Mn^II ions within each molecule. This revised version was published online in June 2006 with corrections to the Cover Date.     

Binuclear iron(III) complexes bridged by terephthalato groups

Six new μ-terephthalato iron(III) binuclear complexes have been prepared and identified: [Fe₂(TPHA)(L)₄]-(ClO₄)₄ [L = 2,2′-bipyridine (bpy); 1,10-phenanthroline (phen); 4,4′-dimethyl-2,2′-bipyridine (Me₂bpy); 5-methyl-1,10-phenanthroline (Me-phen); 5-chloro-1,10-phenanthroline (Cl-phen) and 5-nitro-1,10-phenanthroline (NO₂-phen)]; where TPHA = the terephthalate dianion. Based on the elemental analyses, molar conductance and magnetic moments of room-temperature measurements, and spectroscopic studies, extended TPHA-bridged structures consisting of two iron(III) ions, each in an octahedral environment, are proposed for these complexes. The [Fe₂(TPHA)(Me-phen)₄](ClO₄)₄ (1) and [Fe₂(TPHA)(phen)₄](ClO₄)₄ (2) complexes were characterized by variable temperature magnetic susceptibility (4–300 K) measurements and the observed data were successfully simulated by the equation based on the spin Hamiltonian operator, Ĥ = −2JŜ ₁ Ŝ ₂, giving the exchange integrals J = −1.05 cm⁻¹ for (1) and J = −9.28 cm⁻¹ for (2). This result indicates the presence of a weak antiferromagnetic spin-exchange interaction between the metal ions within each molecule. The influence of the terminal ligand methyl substituents on magnetic interactions between the metals is also discussed. This revised version was published online in June 2006 with corrections to the Cover Date.     

A bis 1,10-phenanthroline ligand leading to octahedral Ru(II) complexes containing a well-defined axis

A bis-chelating ligand (1), made of two 1,10-phenanthroline subunits connected with a p-(CH₂)₂C₆H₄(CH₂)₂- spacer through their 4 positions, has been prepared, using Skraup syntheses and reaction of the anion of 4-methyl-7-anisyl-1,10-phenanthroline with α,α’-dibromo-p-xylene. Complexation of 1 with Ru(CH₃CN)₄Cl₂ and subsequent reaction with 4,4’-dimethyl-2,2’-bipyridine afforded an octahedral Ru(II) tris-diimine complex, in which a well-defined axis running through the terminal anisyl substituents and the central metal has been created, as shown by an X-ray molecular structure analysis.     

COMPLEXES OF 1,8-NAPHTHYRIDINES IX. GROUP VIb METAL CARBONYL COMPLEXES CONTAINING 1,8-NAPHTHYRIDINE, 2-METHYL-1,8-NAPHTHYRIDINE OR trans-DECAHYDRO-1,8-NAPHTHYRIDINE

Abstract

Complexes of the type M(CO)₅(N-N), M(CO)₄(N-N) and M(CO)₃(N-N)₂, where M is Cr, Mo or W and N-N is 1,8-naphthyridine(napy), 2-methyl-1,8-naphthyridine(2-mnapy) or trans-decahydro-1,8-naphthyridine(dhnapy), have been prepared and characterized by infrared and proton magnetic spectroscopy. Complexes of the type Mo(CO)₃(N-N)(napy), where N-N is 1,10-phenanthroline(phen), 2,2′-bipyridine(bipy), 2,9-dimethyl-1,10-phenanthroline(2,9-dmphen) or 2,7-dimethyl-1,8-naphthyridine (2,7-dmnapy), were also prepared and characterized by infrared spectroscopy. In these systems, the various naphthyridine donors exhibit the unique ability to behave as both mono- and bidentate ligands. The mode of bonding between the metal and heterocycles is determined by proton magnetic resonance data.     

Synthesis,characterization, photocleavage,antimicrobial activity and DNA binding of [Co(bpy)2MHPIP]3+, [Co(dmb)2MHPIP]3+, and [Co(phen)2MHPIP]3+ complexes

4-Methyl-2-(2-hydroxyphenyl)imidazo[4,5-f][1,10]phenanthroline) (MHPIP) and its complexes [Co(bpy)₂MHPIP]³⁺ (1) (bpy = 2,2′-bipyridine), [Co(dmb)₂MHPIP]³⁺ (2) (dmb = 4,4′-dimethyl-2,2′-bipyridine), and [Co(phen)₂MHPIP]³⁺ (3) (phen = 1,10-phenanthroline) have been synthesized and characterized by UV/VIS, IR, EA, ¹H, ¹³C-NMR, and mass spectra. The binding of the three complexes with calf-thymus-DNA (CT-DNA) has been investigated by absorption and emission spectroscopy, DNA-melting techniques, viscosity measurements, and DNA cleavage assay. The spectroscopic data and viscosity results indicate that these complexes bind to CT-DNA via an intercalative mode. The complexes also promote photocleavage of plasmid pBR322 DNA and were screened for antimicrobial activity.