新型二茂铁衍生物的合成及其对阴离子识别

利用亚甲基相连的二茂铁咪唑与1,3,5-三溴甲基苯反应得到阴离子受体L,并通过X-射线单晶衍射、红外、核磁、质谱进行表征。通过电化学和~1HNMR实验对阴离子进行识别,实验结果表明受体L和卤素阴离子之间存在着直接的氢键作用,表现出明显的电化学信号响应和核磁位移。     

3—三氯锡基丙酸烯丙酯及其配合物的合成与性质

报道了３－三氯锡基丙酸烯丙酯及其二甲基亚砜，二苄基亚砜，六甲基磷酰胺，三苯基氧化膦，２，２’－联吡啶，８－羟基喹啉及水杨醛缩邻氨基苯酚配合物的合成及性质，利用元素分析，ＩＲ，＾１ＨＮＭＲ等对其结构进行了表征。     

双核铜配合物[Cu2L2]的合成及其晶体结构

采用溶剂热法合成[Cu2L2](L=2,4-dichloro-6-{[(2-hydroxyphenyl)amino]methyl}phenol),并通过红外光谱、元素分析、X-射线单晶衍射进行表征。该化合物属于单斜晶系,P21/n空间群,晶胞参数:a=12.932 2(10),b=5.083 2(4),c=14.760 9(11),β=96.069(7)°,V=1 241.7(11)3,Z=4,Dx=1.924 mg.m-3,μ=2.19 mm-1,F(000)=716,R[F2>2σ(F2)]=0.175,wR(F2)=0.252。结构分析表明,配合物为具有手性对称的平面结构。     

二茂铁单甲酸根桥联的双核铕(Ⅲ)配合物的磁性研究

制备了铕 (Ⅲ )的二茂铁单甲酸基双核配合物 [Eu2 ( μ2 - η2 -OOCFc) 2 (OOCFc) 4 (H2 O) 4 ]·2MeOH·H2 O ,式中 :Fc =( η5-C5H5)Fe( η5-C5H4)。采用单晶X -衍射、元素分析、红外光谱等方法对其进行了结构表征 ,进而采用变温磁化率法测试了该化合物在 5 .0～ 3 0 0K范围内的磁效应 ,结果显示 ,该配合物存在着强的顺磁偶合作用     

新型氨基脲衍生物的合成及其阴离子识别性能

以3-异氰酸丙基三乙氧基硅烷和2, 4-二硝基苯肼为原料,制备了一种氨基脲衍生物阴离子受体R,其结构通过1H/13C NMR等方法表征。在纯DMSO体系下,受体R通过紫外-可见吸收光谱的变化及溶液颜色的显著差别对F-、Ac-和CN-离子表现出良好的识别能力。此外,通过向体系中加入30%的竞争溶剂H2O可以达到对CN-离子的单一识别效应。根据Benesi-Hidebrand方程,受体R单一识别氰根离子的络合常数为8.58 ? 103 L/mol,且检出限为1.47 uM,Job曲线分析证实受体与阴离子的结合比为1 : 1。利用1H NMR滴定实验及理论计算表明受体R与阴离子是以氢键形式相结合的识别机制,未发现脱质子过程。     

二茂铁羟肟酸Cu（Ⅱ）配合物的合成

采用二茂铁羟肟酸与氯化铜反应,合成了一种配合物,通过元素分析、红外光谱确认了配合物的结构。     

μ—草酰二胺铜（Ⅱ）—锰（Ⅱ）双核配合物的合成与磁性研究

合成和表征了两种新的异双核配合物「Ｃｕ（ｏｘｅｎ）Ｍｎ（Ｌ）２」（ＣｌＯ４）２，ｏｘｅｎ表示Ｎ，Ｎ‘－双（２－氨乙基）草酰胺根阴离子；Ｌ为Ｎ，Ｎ，Ｎ’，Ｎ‘０四甲基乙二胺和１，３－丙二胺；测定了配合物「Ｃｕ（ｏｘｅｎ）Ｍｎ（ｔｍｅｎ）２」（ＣｌＯ４）２的变温磁化率（４－３００Ｋ）；其数值用最小二乘法和从自旋Ｈａｍｉｌｔｏｎｉａｎ算符Ｈ＝－２ＪＳ１Ｓ２－ＤＳ２１导出的磁方程拟合，求得交换积分Ｊ＝－６     

双核铼配合物光/电催化还原二氧化碳研究进展

化石燃料的大量使用,以及燃烧化石燃料所释放的大量二氧化碳(CO2),引起越来越严重的环境污染、气候变暖、能源危机等问题.通过光/电催化将CO2转化成为高附加值的化学品或液体燃料,将是解决环境污染、气候变暖、能源危机等问题的最理想方式之一.本文主要综述了近年来双核铼配合物光/电催化还原CO2研究进展.着重对双核铼配合物的...     

二茂铁衍生物及其配合物的研究和应用

详细介绍了二茂铁衍生物及其配合物的研究和应用现状，并指出了该领域今后的研究发展方向。     

Hyaluronan/Diethylaminoethyl Chitosan Polyelectrolyte Complexes as Carriers for Improved Colistin Delivery

Improving the therapeutic characteristics of antibiotics is an effective strategy for controlling the growth of multidrug-resistant Gram-negative microorganisms. The purpose of this study was to develop a colistin (CT) delivery system based on hyaluronic acid (HA) and the water-soluble cationic chitosan derivative, diethylaminoethyl chitosan (DEAECS). The CT delivery system was a polyelectrolyte complex (PEC) obtained by interpolymeric interactions between the HA polyanion and the DEAECS polycation, with simultaneous inclusion of positively charged CT molecules into the resulting complex. The developed PEC had a hydrodynamic diameter of 210–250 nm and a negative surface charge (ζ-potential = −19 mV); the encapsulation and loading efficiencies were 100 and 16.7%, respectively. The developed CT delivery systems were characterized by modified release (30–40% and 85–90% of CT released in 15 and 60 min, respectively) compared to pure CT (100% CT released in 15 min). In vitro experiments showed that the encapsulation of CT in polysaccharide carriers did not reduce its antimicrobial activity, as the minimum inhibitory concentrations against Pseudomonas aeruginosa of both encapsulated CT and pure CT were 1 μg/mL.     

Isoxazole-Derived Aroylhydrazones and Their Dinuclear Copper(II) Complexes Show Antiproliferative Activity on Breast Cancer Cells with a Potentially Alternative Mechanism Of Action

This paper reports the design, synthesis and cytotoxicity studies of two new isoxazole-derived aroylhydrazone ligands and their dinuclear copper(II) complexes. Compounds were fully characterized by various spectroscopic and analytical techniques. The molecular structures of four derivatives were confirmed by X-ray crystallography. The stability of the ligands and the complexes in aqueous medium was monitored spectroscopically. Both the ligands and the complexes were shown to interact with calf thymus DNA (ct-DNA). Additionally, structures containing a phenol pendant arm were significantly more cytotoxic than those carrying a pendant pyridine substituent, reaching sub-micromolar IC₅₀ values on the triple-negative human breast cancer cell line MDA-MB-231. The metal chelation and transchelation ability of the compounds towards Fe^II, Fe^III and Zn^II ions was explored as a possible mechanism of action of these compounds.     

Long-Chain-Amine Metal Complexes as Hydrogenation Catalysts. Heterogenisation on Activated Carbon

The catalytic activity of [PdCl₂(NH₂(CH₂)₁₂CH₃)₂] (named [Pd(TDA)]) and [RhCl(NH₂(CH₂)₁₂CH₃)₃] (named [Rh(TDA)]) complexes for the hydrogenation of cyclohexene has been analysed both in homogeneous phase and heterogenised on activated carbon. The [Rh(TDA)] complex has been found to be more active than the [Pd(TDA)], both homogeneous and heterogenised. Experimental and modelled results indicate that these complexes follow a similar reaction mechanism, but with different rates. A clear positive effect of the carbon support has been found in the case of the complex [Rh(TDA)], which has been related to the anchorage of the aliphatic chains of the amine ligands on the activated carbon pores. Experiments in consecutive catalytic runs show that the heterogenised complexes can be used several times giving an acceptable conversion level.     

Organometallic Coordination Networks Based on \uppi-Bonded Transition Metal Quinonoid Complexes

Hydroquinones -bonded to the transition metal fragments Mn(CO) , Rh(COD)⁺, and Rh[P(OPh)₃]₂⁺ are readily deprotonated to afford anionic -quinone complexes that function as organometalloligands by binding to metal ions through the quinone oxygen atoms. The resulting supramolecular assemblies display a variety of interesting and potentially useful network topologies. An erratum to this article can be found at     

Design of High-Relaxivity Polyelectrolyte Nanocapsules Based on Citrate Complexes of Gadolinium(III) of Unusual Composition

Through nuclear magnetic relaxation and pH-metry, the details of the complexation of gadolinium(III) ions with citric acid (H₄L) in water and aqueous solutions of cationic polyelectrolytes are established. It is shown that the presence of poly(ethylene imine) (PEI) in solution affects magnetic relaxation behavior of gadolinium(III) complexes with citric acid (Cit) to a greater extent than polydiallyldimethylammonium chloride (PDDC). A large increase in relaxivity (up to 50 mM⁻¹s⁻¹) in the broad pH range (4–8) is revealed for the gadolinium(III)–citric acid–PEI system, which is particularly strong in the case of PEI with the molecular weight of 25 and 60 kDa. In weakly acidic medium (pH 3–7), the presence of PEI results in the formation of two tris-ligand associates [Gd(H₂L)₃]³⁻ and [Gd(H₂L)₂(HL)]⁴⁻, which do not exist in aqueous medium. In weakly alkaline medium (pH 7–10), formation of ternary complexes Gd(III)–Cit–PEI with the Gd(III)–to–Cit ratio of 1:2 is evidenced. Using transmission electron microscopy (TEM) and dynamic light scattering techniques (DLS), the formation of the particles with the size of 50–100 nm possessing narrow molecular-mass distribution (PDI 0.08) is determined in the solution containing associate of PEI with tris-ligand complex [Gd(H₂L)₂(HL)]⁴⁻.     

N-Heterocyclic Carbenes and Their Metal Complexes Based on Histidine and Histamine Derivatives of Bacteriopurpurinimide for the Combined Chemo- and Photodynamic Therapy of Cancer

Photodynamic therapy (PDT) is currently regarded as a promising method for the treatment of oncological diseases. However, it involves a number of limitations related to the specific features of the method and the specific characteristics of photosensitizer molecules, including tumor hypoxia, small depth of light penetration into the tumor tissue, and low accumulation sensitivity. These drawbacks can be overcome by combining PDT with other treatment methods, for example, chemotherapy. In this work, we were the first to obtain agents that contain bacteriopurpurinimide as a photodynamic subunit and complexes of gold(I) that implement the chemotherapy effect. To bind the latter agents, N-heterocyclic carbenes (NHC) based on histidine and histamine were obtained. We considered alternative techniques for synthesizing the target conjugates and selected an optimal one that enabled the production of preparative amounts for biological assays. In vitro studies showed that all the compounds obtained exhibited high photoinduced activity. The C-donor Au(I) complexes exhibited the maximum specific activity at longer incubation times compared to the other derivatives, both under exposure to light and without irradiation. In in vivo studies, the presence of histamine in the NHC-derivative of dipropoxy-BPI (7b) had no significant effect on its antitumor action, whereas the Au(I) metal complex of histamine NHC-derivative with BPI (8b) resulted in enhanced antitumor activity and in an increased number of remissions after photodynamic treatment.     

Synthesis,In Vitro,and Computational Studies of PTP1B Phosphatase Inhibitors Based on Oxovanadium(IV) and Dioxovanadium(V) Complexes

One of the main goals of recent bioinorganic chemistry studies has been to design and synthesize novel substances to treat human diseases. The promising compounds are metal-based and metal ion binding components such as vanadium-based compounds. The potential anticancer action of vanadium-based compounds is one of area of investigation in this field. In this study, we present five oxovanadium(IV) and dioxovanadium(V) complexes as potential PTP1B inhibitors with anticancer activity against the MCF-7 breast cancer cell line, the triple negative MDA-MB-231 breast cancer cell line, and the human keratinocyte HaCaT cell line. We observed that all tested compounds were effective inhibitors of PTP1B, which correlates with anticancer activity. [VO(dipic)(dmbipy)]·2 H₂O (Compound 4) and [VOO(dipic)](2-phepyH)·H₂O (Compound 5) possessed the greatest inhibitory effect, with IC₅₀ 185.4 ± 9.8 and 167.2 ± 8.0 nM, respectively. To obtain a better understanding of the relationship between the structure of the examined compounds and their activity, we performed a computer simulation of their binding inside the active site of PTP1B. We observed a stronger binding of complexes containing dipicolinic acid with PTP1B. Based on our simulations, we suggested that the studied complexes exert their activity by stabilizing the WPD-loop in an open position and limiting access to the P-loop.     

Formation of Multicolor Nanogels Based on Cationic Polyfluorenes and Poly(methyl vinyl ether-alt-maleic monoethyl ester): Potential Use as pH-Responsive Fluorescent Drug Carriers

In this study, we employed the copolymer poly(methyl vinyl ether-alt-maleic monoethyl ester) (PMVEMA-Es) and three fluorene-based cationic conjugated polyelectrolytes to develop fluorescent nanoparticles with emission in the blue, green and red spectral regions. The size, Zeta Potential, polydispersity, morphology, time-stability and fluorescent properties of these nanoparticles were characterized, as well as the nature of the interaction between both PMVEMA-Es and fluorescent polyelectrolytes. Because PMVEMA-Es contains a carboxylic acid group in its structure, the effects of pH and ionic strength on the nanoparticles were also evaluated, finding that the size is responsive to pH and ionic strength, largely swelling at physiological pH and returning to their initial size at acidic pHs. Thus, the developed fluorescent nanoparticles can be categorized as pH-sensitive fluorescent nanogels, since they possess the properties of both pH-responsive hydrogels and nanoparticulate systems. Doxorubicin (DOX) was used as a model drug to show the capacity of the blue-emitting nanogels to hold drugs in acidic media and release them at physiological pH, from changes in the fluorescence properties of both nanoparticles and DOX. In addition, preliminary studies by super-resolution confocal microscopy were performed, regarding their potential use as image probes.     

Synthesis and Characterization of Co Nanocomposite Based on Poly(benzimidazole-amide) Matrix and Their Behavior as Catalyst in Oxidation Reaction

2,6-Bis(5-amino-1H-benzimidazol-2-yl)pyridine was prepared and characterized by Fourier transform infrared spectroscopy, elemental analysis, ¹H-NMR, and ¹³C-NMR spectroscopic methods. Then a new poly(benzimidazole-amide) was synthesized by polymerization of the corresponding diamine and isophthalic acid. The obtained poly(benzimidazole-amide) exhibited good yield and high thermal stability. Due to the existence of benzimidazole moieties in polymer’s structure, it has the tendency to form complexes with metal ions. So, a new poly(benzimidazole-amide)/Co nanocomposite was prepared. Morphological studies revealed that metal nanoparticles were dispersed in the polymer matrix without any aggregation. poly(benzimidazole-amide)/Co nanocomposite was used as a catalyst in the oxidation of ethyl benzene to acetophenone with tert-butyl hydroperoxide.