Synthesis and biological activity of a platinum(II) 6-phenyl-2,2'-bipyridine complex and its dimeric analogue

We have synthesized (pyridyl)-(6-phenyl-2,2'-bipyridine)platinum(II) hexafluorophosphate (1) and its corresponding dimer, micro-N,N'-bis(isonicotinyl)-1,6-hexanediamino bis-[6-phenyl-2,2'-bipyridine-platinum(II)] dichloride (2). The DNA binding constants of 1 and 2 at 20 degrees C were determined by absorption titration to be 2.25 x 10(4) M(-1) and 3.07 x 10(6) M(-1), respectively. Compound 1 showed an AT preference, while 2 had no base preference. The binding site sizes of 2 for [poly(dA-dT)](2), calf thymus DNA (ctDNA), and [poly(dG-dC)](2), as determined by fluorescence titration, were 6.6, 4.0, and 2.8 bp, respectively. Compound 2 probably bound to [poly(dA-dT)](2) through bisintercalation, and to [poly(dG-dC)](2) by monointercalation. Binding of DNA by both complexes is favorable, since the binding free energies of 1 and 2 were estimated to be -5.8 and -8.7 kcal mol(-1), respectively. The results of viscosity measurements and gel mobility shift assay demonstrated that binding of 1 and 2 caused DNA lengthening. The cytotoxicities of the complexes in various human cancer cell lines were determined by MTT assay. Complex 2 exhibited cytotoxicity comparable to that of cisplatin, and was more toxic than 1 by an order of magnitude.     

Phase transitions in R2 SnCl6-type crystals (R = NH3 C2H3, NH3C2H5 and N(CH3)4)

The thermal dilatation in (NH₃ ·CH₃) SnCl₆, (NH₃ · C₂H₅) SnCl₆ and [N(CH₃)] SnCl₆ was measured, and as the results it has turned out that (NH₃ ⁶·C₂H₅) SnCl₆ and [N(CH₃)₄]₂ SnCl₆ undergo the first order transitions at 128 K and 158 K, respectively. The low temperature phases of (NH · C₂H₅) SnCl₆ and [N(CH₃)₄]₂ SnC1₆ are found to be monoclinic and tetragonal, respectively, No phase transition was observed in (NH₃ ·CH₃)₂ SnCl₆ down to 77 K.     

Synthesis, in vitro cytotoxicity, and interaction with DNA of platinum(II) complexes with N-monocycloalkyl derivatives of 1R,2R-diaminocyclohexane as carrier ligands

A series of platinum(II) complexes with N-monocyclopentyl/cyclohexyl derivatives of 1R,2R-diaminocyclohexane as carrier ligands and dicarboxylate anions as leaving groups were synthesized and characterized. All complexes were characterized by elemental analysis, IR, (1)H NMR, and (13)C NMR spectroscopy, as well as ESIMS. The in vitro antiproliferative activities were tested by MTT assay against four human cancer cell lines; breast carcinoma (MCF-7) and colon cancer (HCT-116) cells were particularly sensitive, especially to complexes 1f (IC(50) =9.81 and 1.49 μM) and 2f (IC(50) =4.59 and 0.36 μM). Flow cytometry indicated that representative compounds exert cytotoxicity toward MCF-7 and HCT-116 cells through induction of apoptosis and blockage of cell-cycle progression in the S phase, similar to cisplatin. The interaction between the platinum(II) complexes and pET22b plasmid DNA was observed by agarose gel electrophoresis, revealing that complex 2f has the capacity to distort plasmid DNA in a manner distinct from that of oxaliplatin.     

Structure and catalytic activity of a hexarhenium cluster-supported copper cubanes [{Cu4(μ-OH)4(NH3)7}2{Re6Se8(CN)6}][Re6Se8(CN)6] · 2H2O

The first hexarhenium cluster-supported Cu₄(OH)₄ cubanes had been synthesized. The complex displayed a belt-like one-dimensional structure with dangling Cu₄ cubanes. As a heterogeneous catalyst, the complex showed a high catalytic activity in the transesterification of a range of esters with methanol under the mild conditions. Moreover, it can be reused without any loss of activity through five runs with ester, which suggests that this catalyst is an efficient, mild, and easily recyclable one for the alcoholysis of esters.     

Synthesis,characterizations, and crystal structure of a novel layered phosphonate: Zn2Cl[O3PCH2N(CH2CH2)2O][O3PCH2NH(CH2CH2)2O]

A novel layered zinc phosphonate, Zn₂Cl[O₃PCH₂N(CH₂CH₂)₂O][O₃PCH₂NH(CH₂CH₂)₂O] 1 has been synthesized by hydrothermal reaction at 180 °C and structurally characterized by single crystal X-ray diffraction as well as with infrared spectroscopy, elemental analysis and thermogravimetric analysis. The interconnection of Zn(1)O₄, Zn(2)O₂NCl and CPO₃ tetrahedra via corner-sharing forms a double layer structure with a channel system along b-axis direction. The result of connections in this manner is the formation of 8- and 16-atom windows that are parallel to one another and run in the a-axis direction. The morpholinyl groups of the ligands are orientated toward the interlayer space.     

Synthesis and crystal structure of dinuclear [(thf)3YCl2{μ-P(H)C6H2-2,4,6-Me3}]2 with seven-coordinate yttrium atoms

The metathesis reaction of KP(H)Mes with YCl₃ in tetrahydrofuran yields dinuclear [(thf)₃YCl₂{μ-P(H)Mes}]₂ (1) with a yield of 26% (Mes = mesityl, C₆H₂-2,4,6-Me₃). The seven-coordinate yttrium atoms exhibit pentagonal bipyramidal coordination spheres with bridging mesitylphosphanide substituents. The Y₂PC fragments are nearly planar with an average Y–P bond length of 296.0 pm. The P-bound hydrogen atoms are perpendicular to these planes. The small ¹J(P,H) coupling constant of 125 Hz is in agreement with the picture that the H atom binds mainly to the p-orbital of the phosphorus atom.     

配位离子液体［3（CH3CH2）4N+Cl-·（NH2）2CO］的合成及表征

采用尿素和氯化四乙基铵为原料，合成了一种新型的配位离子液体，并通过红外和X－射线粉末衍射对其结构进行了表征。结果表明，尿素和氯化四乙基铵发生反应，使得原来尿素羰基峰由1690.72cm－1转移到了1619.10cm－1。由X－射线粉末衍射图可以看出，在2θ = 30.37°处有新的衍射峰。通过差热－热重分析，配位离子液体在室温到250℃可以稳定存在，与其他有机溶剂相比具有良好的稳定性。     

The effect of density functional and dispersion interaction on structure and bonding analysis of uranium(VI) nitride complex [NU{N(CH2CH2NSiMe3)3}]: A theoretical study

Geometry and bonding energy analysis of uranium(VI) nitride complex [NU{N(CH₂CH₂NSiMe₃)₃}] were investigated with the DFT, DFT-D3 and DFT-D3(BJ) methods using density functionals (BLYP, BP86, PW91, PBE, revPBE and TPSS). The BLYP functional yields a UN bond distance of 1.788 Å for the model complex [NU{N(CH₂CH₂NSiMe₃)₃}] which is in close agreement with the experimental value of the UN bond distance of 1.799(7) Å for [NU{N(CH₂CH₂NSiⁱPr₃)₃}]. The calculated Mayer bond order (2.95) and Gopinathan–Jug bond order (3.18) indicate that the UN bond in this complex is essentially UN triple bonds. The electrostatic interaction is significantly smaller than the covalent bonding. The bond dissociation energy (BDE) is largest for the functional PBE and smallest for the functional TPSS. The DFT-D3 dispersion corrections are 5.3 kcal/mol (BLYP) and 5.0 kcal/mol (TPSS).     

Synthesis and structure of a mixed valence metal carbitoxide complex: Eu3[O(CH2CH2O)2CH2CH3]4(OC6H3iPr2-2,6)3

The direct reaction of europium metal with HO(CH₂CH₂O)₂CH₂CH₃ followed by treatment with 2,6-ⁱPr₂C₆H₃OH leads to the crystallographically-characterizable, mixed valent carbitoxide product Eu₃[O(CH₂CH₂O)₂CH₂CH₃]₄(OC₆H₃ⁱPr₂-2,6)₃ (1), which contains bridging alkoxide ligands and both terminal and bridging aryloxide ligands.     

Synthesis, structure, and photovoltaic property of a nanocrystalline 2H perovskite-type novel sensitizer (CH3CH2NH3)PbI3

A new nanocrystalline sensitizer with the chemical formula (CH₃CH₂NH₃)PbI₃ is synthesized by reacting ethylammonium iodide with lead iodide, and its crystal structure and photovoltaic property are investigated. X-ray diffraction analysis confirms orthorhombic crystal phase with a = 8.7419(2) Å, b = 8.14745(10) Å, and c = 30.3096(6) Å, which can be described as 2 H perovskite structure. Ultraviolet photoelectron spectroscopy and UV-visible spectroscopy determine the valence band position at 5.6 eV versus vacuum and the optical bandgap of ca. 2.2 eV. A spin coating of the CH₃CH₂NH₃I and PbI₂ mixed solution on a TiO₂ film yields ca. 1.8-nm-diameter (CH₃CH₂NH₃)PbI₃ dots on the TiO₂ surface. The (CH₃CH₂NH₃)PbI₃-sensitized solar cell with iodide-based redox electrolyte demonstrates the conversion efficiency of 2.4% under AM 1.5 G one sun (100 mW/cm²) illumination.     

配合物Ni(C_6H_6NO_3S)_2(H_2O)_4的合成、表征及热稳定性

用常温挥发法合成了一个新颖的单核配合物Ni(C6H6NO3S)2(H2O)4,并利用红外光谱、元素分析、热重分析及X-射线单晶衍射法对其结构进行了表征。结果表明,该配合物晶体属于单斜晶系,P121/n1空间群,晶胞参数为:a=1.191 2 nm,b=0.633 nm,c=1.224 nm,β=108.936°,Z=2,R1=0.027 1,wR2=0.100 7。在标题配合物中,每个Ni2+与4个H2O分子的氧原子及来自两个邻氨基苯磺酸的两个氮原子配位,形成一个畸变的八面体构型。在该配合物中,磺酸基的氧原子没有配位,这表明在该体系下,H2O的配位性能优于磺酸基氧原子。     

Tetra- and hexanuclear cage molecules based on diruthenium tetracarbonyl sawhorse units: Synthesis and molecular structure of [{Ru2(CO)4(PPh3)2}2(O2CCH2CO2)2] and [{Ru2(CO)4(PMe3)2}3(O2CC6H4CO2)3]

The thermal reaction of Ru₃(CO)₁₂ with malonic acid, followed by the addition of the corresponding ligand, yields the tetranuclear ruthenium complexes [{Ru₂(CO)₄L₂}₂(O₂CCH₂CO₂)₂] (L = PPh₃: 1, L = 3,5-Me₂NC₅H₃: 2), while the reaction of Ru₃(CO)₁₂ with terephthalic acid, followed by the addition of the corresponding ligand, gives rise to the formation of the hexanuclear ruthenium complexes [{Ru₂(CO)₄L₂}₃(O₂CC₆H₄CO₂)₃] (L = PMe₃: 3, L = 3,5-Me₂NC₅H₃: 4). The single-crystal X-ray structure analyses for 1 and 3, reveal both cages to consist of Ru₂(CO)₄ sawhorse units, 1 being a molecular loop, while 3 is a molecular triangle.     

Reversible nitro–nitrito inter-conversion in a simple mono-nuclear nickel(II) complex [NiII{C6H4(NH2)2}2(NO2)2] in the solid state

A simple mono-nuclear nickel(II) complex [Ni^II{C₆H₄(NH₂)₂}₂(NO₂)₂] (1) has been synthesized from an aqueous solution containing nickel chloride, sodium nitrite and ortho-phenylenediamine (opda). When crystals of compound 1 are heated in the temperature range of 110–120 °C for 5 min, their brown color changes to blue, that is accompanied by the conversion of nitro group (N-coordinated) in compound 1 into nitrito group (O-coordinated) in compound [Ni^II{C₆H₄(NH₂)₂}₂(ONO)₂] (2). On cooling, the nitrito compound 2 goes back to parent nitro-compound 1.     

Synthesis,structure and catalytic properties of a novel zirconium guanidinato complex [Zr{ArNC(NMe2)N(SiMe3)}(μ2-Cl)Cl2]2[Ar = 2,6-iPr2-C6H3]

A novel non-symmetric zirconium guanidinato complex, [{Zr{ArNC(NMe₂)N(SiMe₃)}(μ₂-Cl)Cl₂}₂] (Ar = 2,6-ⁱPr₂-C₆H₃), was synthesized and structurally characterized. Catalytic studies showed that the zirconium complex was active for ethylene polymerization with the activity of 4.98 × 10⁵ g PE/mol Zr h. The influences of cocatalysts, Al/Zr molar ratios and ethylene pressures on the activities were investigated.     

First structurally characterized anion exchange product of noval cyclohexane containing substituted thio piperazinium chloride [C6H11S(CH2)3C4H9N2C6H5Cl (L1Cl)]: Synthesis,crystal structure and supramolecularity of (L1NO3)

[C₆H₁₁S(CH₂)₃C₄H₉N₂C₆H₅Cl (L¹Cl)] has been synthesized by reaction of cyclohexyl thiol with 1-(chlorophenyl)-4-(3-chloropropyl) piperazine hydrochloride (P¹) under dry nitrogen atmosphere. The L¹Cl on reaction with Cd(NO₃)₂ forms a compound [L¹NO₃] having NHO hydrogen bonding. The single crystal structure of the compound L¹NO₃ is solved. The characteristic feature of these reactions is the retention of the piperazinium character from starting material (P¹) to ligand formation (L¹Cl) as well as in the formation of anion exchange product (L¹NO₃). L¹Cl and L¹NO₃ are characterized on the basis of physico-chemical and spectral (ESI Mass, FT-IR, ¹H, ¹³C and DEPT 135° ¹³C {¹H} NMR) studies. The proton and carbon-13 NMR spectra of L¹Cl and L¹NO₃ are characteristic. L¹NO₃ crystallizes in orthorhombic system with Pbca space group. Both piperazine and cyclohexane rings adopt the chair conformation with N₁, N₂ and C₁₄, C₁₇ out of plane. Geometry around quaternary nitrogen atom is distorted tetrahedral as revealed by the bond angles.     

氢键连接的二维超分子化合物[(Bi2Cl4I6)(H2tmdp)2(CH3OH)4]的合成与晶体结构

合成了标题化合物,并对其结构进行了X-射线单晶衍射测定。该化合物属三斜晶系,空间群P1,晶胞参数a=1.1690(2)nm,b=1.2025(2)nm,c=1.1114(2)nm,α=116.07(3)°,β=101.17(3)°,γ=88.21(3)°,Z=1。晶体结构中,每个铋离子均呈现出六配位并与另一铋离子通过共用卤素离子形成双核[Bi2Cl4I6]4-配阴离子,1,3-二(4-哌啶基)丙烷完全质子化形成[H2tmdp]2+配阳离子,配阴离子[Bi2Cl4I6]4-、配阳离子[H2tmdp]2+以及溶剂CH3OH分子之间通过复杂的氢键形成二维层状超分子结构。