Cyanostilbene-based near-infrared emissive platinum(Ⅱ) metallacycles for cancer theranostics

In this work,a near-infrared emissive dipyridyl ligand was synthesized and used to prepare three platinum(Ⅱ) metallacycles with different shapes via metal-coordination-driven self-assembly with different platinum(Ⅱ) precursors.These metallacycles were further used for both cell imaging and cancer therapy,offering a new type of theranostic agents towards cancer treatment.     

Synthesis of novel magnetic sulfur-doped Fe_3O_4 nanoparticles for efficient removal of Pb(Ⅱ)

In this work, we report the synthesis of magnetic sulfur-doped Fe_3O_4 nanoparticles (Fe_3O_4:S NPs) with a novel simple strategy,which includes low temperature multicomponent mixing and high temperature sintering. The prepared Fe_3O_4:S NPs exhibit a much better adsorption performance towards Pb(Ⅱ) than bare Fe_3O_4 nanoparticles. FTIR, XPS, and XRD analyses suggested that the removal mechanisms of Pb(Ⅱ) by Fe_3O_4:S NPs were associated with the process of precipitation (formation of PbS), hydrolysis,and surface adsorption. The kinetic studies showed that the adsorption data were described well by a pseudo second-order kinetic model, and the adsorption isotherms could be presented by Freundlich isotherm model. Moreover, the adsorption was not significantly affected by the coexisting ions, and the adsorbent could be easily separated from water by an external magnetic field after Pb(Ⅱ) adsorption. Thus, Fe_3O_4:S NPs are supposed to be a good adsorbents for Pb(Ⅱ) ions in environmental remediation.     

Synthesis,Crystal Structure and in vitro Anticancer Studies of 1,2-Bis-benzimidazole-phenyl Copper(Ⅱ) Complex

One new benzimidazole derivative copper(II) complex 1(C10H6Cu N2, Mr = 217.71) has been synthesized and characterized by FT-IR and X-ray single-crystal diffraction. It crystallizes in orthorhombic, space group Pbcn with a = 17.417(2), b = 8.9963(8), c = 11.3432(9) ?, V = 1777.3(3) ?3, Z = 8, μ(Mo Kα) = 2.403, F(000) = 872, Dc = 1.627 g/cm3. The final R = 0.0598 for 1153 observed reflections with I 2σ(I) and w R = 0.17 for all data. The in vitro anti-cancer activities of 1, Cu Cl2 and the benzimidazole ligand L were investigated using human cervical(Hela) and hepatocellular carcinoma(Hep-G2) cancer cell lines. The copper(II) complex can greatly inhibit the cell proliferation and show stronger cytotoxic activities against the tested cancer cell lines than both the ligand and copper(II) salt.     

Synthesis and Crystal Structure of [Ni(Ⅱ)(L)(py)3]·(py)

The title complex, C37H34N6NiO5, has been prepared and characterized by X-ray diffraction analysis. It crystallizes in the monoclinic system, space group P21/c with a = 1.15244(8), b = 1.69679(12), c = 1.78341(13) nm, β = 102.2320(10)°, V = 3.4082(4) nm3, Z = 4, Mr = 701.41, F(000) = 1464, Dc = 1.367 g/cm3 and μ(MoKα) = 0.622 mm-1. The structure was refined to R = 0.0459 and wR = 0.1199 for 5718 observed reflections. The intramolecular hydrogen bonds in the crystal structure play important roles in the title complex's thermostability.     

Synthesis of a Rare Doubly-interpenetrating Zinc(Ⅱ) Coordination Polymer for Applications in Photocatalysis

A rare doubly-interpenetrating Zn-MOF(complex 1), formulated as {[Zn(tci)-(bpy)(NO_3)·DMF·0.5 CH_3CN}_n(H_3tci = tri(2-carboxyethyl) isocyanurate, bpy = 4,4-bipyridine), has been constructed under solvothermal conditions and characterized by single-crystal X-ray diffraction, infrared spectroscopy(IR) and powder X-ray diffraction(PXRD). 1 crystallizes in monoclinic system, space group C2/c with a = 21.5759(4), b = 12.87221(18), c = 26.4917(5) ?, β = 109.462(2)°, V = 6937.1(2) ?~3, C_(50)H_(56)N_(14)O_(27)Zn_4, Mr = 1546.56, Z = 4, D+c = 1.481 g·cm~(-3), μ = 2.325 mm~(-1) λ = 1.54178 ?, F(000) = 3160, S = 1.041, R = 0.0621 and wR = 0.1773. 1 features a two-fold interpenetrating 3 D hms topology. Moreover, the thermal stabilities, fluorescent and CO_2 adsorption properties were investigated. Complex 1 showed highly encoura-ging photocatalytic degradation of toxic dye molecules with a potential application in wastewater purification.     

Synthesis,Structure and Norbornene Polymerization Activity of a Novel Palladium(Ⅱ) Complex with N,N-bis(2-benzoyl-3-oxobutane)-trans-1,2-diaminocyclohexane Ligand

The title complex N,N-bis(2-benzoyl-3-oxobutane)-trans-1,2-diaminocyclohexane-palladium(C28H28N2PdO4) has been synthesized by the reaction of N,N-bis(2-benzoyl-3-oxobutane)-trans-1,2-diamino-cyclohexane with PdCl2,and characterized by elemental analysis,IR spectrum,WAXD and TG.The spatial structures of the complex have been confirmed by single-crystal X-ray diffraction analysis.The compound crystallizes in the monoclinic system,space group C2/c with a = 29.763(6),b = 10.320(2),c = 18.921(4) ,β = 102.75(3)°,V = 5668(2) 3,C28H28N2PdO4·CH3OH,Mr = 594.97,Z = 8,Dc = 1.394 g/cm3,μ(MoKα) = 0.694 mm-1,F(000) = 2448,T = 293(2) K,R = 0.0572 and wR = 0.1347(I 2(I)).The compound was investigated for the catalytic behavior towards norbornene(NB) vinyl addition polymerization.And the palladium complex showed excellent catalytic activity up to 9.97×106 g of PNB(mol of Pd)-1 h-1 with high monomer conversion using methylaluminoxane(MAO) as a cocatalyst.     

Synthesis,characterization, and cytotoxicity of complexes of platinum(II) with 2,2′-bipyridine and N-benzoyl-L-amino acid dianion

Four new platinum(II) complexes (1–4) with N-benzoyl-L-amino acid and bipy were synthesized and characterized by elemental analysis, IR, UV, ¹H NMR, and mass spectra. The crystal structure of 1 was determined by X-ray diffraction analysis. Cytotoxicities were measured by MTT and SRB assays. Complexes 1–4 exert cytotoxicity with selectivity against HL-60, Bel-7402, BGC-823, and KB cell lines. This suggests that amino acids and acylated groups have important effects on cytotoxicity; the cytotoxicity is also related to the species of tumor cells, but the IC₅₀ values do not show definite correlation with the variation of amino acids and acylated groups.     

Solvation model for acetic acid in binary mixtures of cyclohexane–1,2-dichloroethane

The partition of acetic acid between aqueous solutions and various binary mixtures of 1,2-dichloroethane and cyclohexane were studied at 30.0 °C. The observed nonlinearities of both monomer partition coefficient and dimerization constant in the organic phase with the mole fraction of 1,2-dichloroethane are interpreted in terms of the preferential solvation of various solvation sites of the involved species. Two polar sites were identified for the monomer each with a solvation preference by 1,2-dichloroethane seven times that by cyclohexane. This preference decreases to about two upon dimerization.     

Mixtures obtained by reacting trans-(±)-1,2-diaminocyclohexane with acetylacetone in the presence of simple cobalt(II) salts

In the absence of a metal ion, racemic trans-1,2-diaminocyclohexane (trans-(±)DCH) reacts with acetylacetone (acacH) (1:2.5 mole ratio) to form the bisoxoenamine condensation product, boe (1). CoCl₂·6H₂O and Co(ClO₄)₂·6H₂O each react with trans-(±)DCH in air to give complexes containing the oxidised Co(III) ion, [Co((±)DCH)₃]³⁺, which does not subsequently react with added acacH to give a Schiff base complex. Mixtures of complexes are obtained from one-pot reactions involving trans-(±)DCH, a simple Co(II) salt and acacH (1:1:2.5 mole ratio). When CoCl₂·6H₂O is used, the mixed-ligand Co(II) complex [Co((±)DCH)Cl₂] (4) precipitates first and, after a period of weeks, the Co(II) complex (diazH)₂[CoCl₄] (5) (diazH⁺ is a diazepinium cation), the Co(II) complex [Co(boe)Cl₂]_n (6) and the Co(III) complex [Co(acac)₃] (7), co-crystallise from the mother liquor. Using Co(ClO₄)₂·6H₂O in the reaction with trans-(±)DCH and acacH also gives a mixture of products. Complexes 7, the Co(II) complex [Co₂(acac)₄(H₂O)₂][Co(acac)(H₂O)₄]ClO₄·EtOH (8) and the Co(III) complex [Co(acac)₂(±)DCH]ClO₄ (9) co-crystallise. Complexes 1, 5, 7, 8 and 9 were characterised using X-ray crystallography. The major difference between using CoCl₂·6H₂O and Co(ClO₄)₂·6H₂O in reactions involving (±)DCH and acacH is that no DCH/acacH condensation products are identified in the product mixtures when the perchlorate salt is employed.     

Photoactivation of dichloro(ethylenediamine)platinum(II)

Photolysis of dimethylsulfoxide (dmso) solutions of the compound Pt(en)Cl₂, where en=ethylene-1,2-diamine, leads to solvolysis of the complex and formation of Pt(en)(dmso)Cl⁺. The reaction follows clean pseudo-first-order kinetics with parallel photolytically activated and thermally activated paths. Both paths are first-order in both Pt(en)Cl₂ and solvent. Eyring analysis of the rate constants for 25 °C≤T≤55 °C yielded a Gibbs energy of activation of 96 kJ mol⁻¹ for the thermal pathway and no measurable activation barrier for the photochemical pathway. The quantum yield for the photochemical path is 0.22, as determined using ferrioxalate actinometry.     

N-(4-Methoxyphenyl)-substituted bicyclic isothioureas: effect on morphology of cancer cells

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The solvent-initiated photolysis of dichloro(2,2'-bipyridine)platinum(II) in chloroform

Under 254 nm irradiation, [Pt(bpy)Cl2] is converted to [Pt(bpy)Cl4] in a solvent-initiated process. The reaction is very nearly zero order throughout. The rate decreases slightly with increasing starting concentration. These characteristics can be rationalized by a rate law of the form afs, where fs is the fraction of light absorbed by chloroform. The species that reacts with [Pt(bpy)Cl2] is believed to be CCl3OO.     

Synthesis,cytotoxicity, and interaction with DNA of platinum(II) complexes of (1R,2R)-N1-2-amyl-1,2-diaminocyclohexane

(1R,2R)-N¹-2-amyl-1,2-diaminocyclohexane, which has an amyl substituent as compared with 1,2-diaminocyclohexane, was used as the carrier group to construct three platinum(II) complexes. MTT assay revealed that the complexes showed decent cytotoxicity against all of the four tested tumor cell lines with the IC₅₀ values ranging from 1.08 to 253.36 μM. Particularly, the IC₅₀ values of 2 against A549 and HCT-116 reached 3.32 and 1.08 μM, respectively, which were much lower than those of cisplatin and oxaliplatin. Flow cytometry demonstrated that 2 inhibited HepG2 cells proliferation and caused cytotoxicity by inducing apoptosis and arresting cells in the G2 phase. Furthermore, agarose gel electrophoresis showed that 2 had the ability to interact with DNA in a manner different from cisplatin and oxaliplatin, indicating the carrier ligand with an alkyl moiety had an influence on the action mode of the complex.     

Synthesis of a platinum(II) complex of chloroanilic acid

Conclusions A platinum(II) complex of chloroanilic acid was synthesized. This complex is isostructural to the analogous palladium complex and has the formula [Pt(C₆O₄Cl₂)Cl₂]K₂'H₂O.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2123–2124, September, 1986.The authors thank O. N. Krasochka for a preliminary x-ray diffraction analysis of this complex.     

6-氨基-2-取代吲哚-3-羧酸乙酯及其衍生物的合成与生物活性评价

以2,4-二硝基氯苯和乙酰乙酸乙酯为原料, 经过亲核置换、还原-环化协同反应, 合成了6-氨基-2-甲基吲哚-3-羧酸乙酯, 而后在催化剂作用下, 与乙酰乙酸乙酯反应生成烯胺, 环化合成9-羟基-2,7-二甲基吡咯(2,3-f)喹啉-3-羧酸乙酯; 类似地, 合成了6-氨基-2-苯基吲哚-3-羧酸乙酯和6-氨基-2-(呋喃-2'-基)吲哚-3-羧酸乙酯. 其结构均由¹H NMR, IR以及MS波谱数据表征. 所得化合物具有抑制肺癌A549细胞生长的活性, 其抑制效果具有浓度依赖性.     

Kinetics and mechanism of aqua ligand substitution from cis-diaqua(cis-1,2-diaminocyclohexane)platinum(II)perchlorate by diethyldithiocarbamate anion in aqueous medium

The kinetics of the interaction of diethyldithiocarbamate (Et₂DTC) with [Pt(dach)(H₂O)₂]²⁺ (dach = cis-1,2-diaminocyclohexane) have been studied spectrophotometrically as a function of [Pt(dach)(H₂O)₂ ²⁺], [Et₂DTC] and temperature at a particular pH (4.0). The reaction proceeds via rapid outer sphere association complex formation followed by two slow consecutive steps. The first step involves the transformation of the outer sphere complex into an inner sphere complex containing a Pt–S bond and one aqua ligand, while the second step involves chelation when the second aqua ligand is replaced. The association equilibrium constant K _E and two rate constants k ₁ and k ₂ have been evaluated. Activation parameters for both the steps have been calculated (∆H ₁ ^# = 66.8 ± 3.7 kJ mol⁻¹, ∆S ₁^# = −81 ± 12 JK⁻¹ mol⁻¹ and ∆H ₂^# = 95.1 ± 2.8 kJ mol⁻¹, ∆S ₂^# = −34.4 ± 9.1 JK⁻¹ mol⁻¹). The low enthalpy of activation and negative entropy of activation indicate an associative mode of activation for both the steps.     

Use of reversed-phase h.p.l.c. for determination of the hydrolysis rate constants of dichloro(1,2-diarylethylenediamine)platinum(II) complexes

Summary The rates of the Pt-Cl hydrolysis reactions for a series of dichloro(1,2-diarylethylenediamine)platinum(II) complexes were measured by means of a reversed-phase h.p.l.c. assay. The compounds were hydrolysed at rates comparable to those published for [PtCl₂(en)]. The configuration of the 1,2-diarylethylenediamine ligand (meso versus racem), as well as the type of substituent (i.e. OMe, CN or F) in the para-position of the aromatic rings had only a marginal influence on the rates of hydrolysis; however, the introduction of ortho-chloro substituents onto the aromatic rings markedly slowed the hydrolysis reactions. In contrast to the reported pH-dependency of the hydrolysis rates of cisplatin, changes in proton concentration had no effect on the hydrolysis rates of the title compounds over a pH range of 2.2–7.2. The activation parameters H and S of the Pt-Cl hydrolysis rates were comparable to those reported for similar Pt^II compounds.     

Inhibition of cell proliferation,invasion and migration by the cardenolides digitoxigenin monodigitoxoside and convallatoxin in human lung cancer cell line

Cardiac glycosides consist of a large family of naturally derived compounds that are clinically used to treat congestive heart failure, and also present anticancer properties. In this study, the cytotoxic effects of two cardenolides, digitoxigenin monodigitoxoside (DGX) and convallatoxin (CON) were screened in four human tumour cell lines. Both compounds showed anti-proliferative effects in all tumour cells, at nanomolar concentrations. Since the human lung cancer cell line A549 was the most sensitive, we investigated the anti-proliferative, anti-migratory and anti-invasive effects of these cardenolides. DGX and CON reduced A549 cell migration, being able to reduce more than 90% of cell invasion. Their effects on the expression of key regulators of metastatic mechanism showed decreased levels of MMP-2, MMP-9 and p-FAK. Both compounds also presented low toxicity for healthy cells. Finally, this work provides the first insights into the effects of these cardenolides on key steps of lung cancer metastasis.