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991.
S. S. Qian X. L. Zhao L. H. Pang Z. L. You H. L. Zhu 《Russian Journal of Coordination Chemistry》2016,42(5):345-350
A new centrosymmetric mononuclear copper(II) complex [Cu(L)2](ClO4)2 (I) and a new centrosymmetric mononuclear nickel(II) complex [Ni(L)2(MeOH)2](ClO4)2 (II), where L is the zwitterionic ligand 2-bromo-4-chloro-6-[(2-methylammonioethylimino)methyl]phenolate, have been prepared from the Schiff base 2-bromo-4-chloro-6-[(2-methylaminoethylimino)methyl]phenol with copper perchlorate and nickel perchlorate, respectively. The complexes were characterized by elemental analysis, infrared spectra, and single-cyrstal X-ray diffraction (CIF files CCDC nos. 1408054 (I) and 1407973 (II)). Complex I crystallizes in the monoclinic space group P21/c with unit cell dimensions a = 7.7736(4), b = 21.608(1), c = 8.5194(4) Å, β = 93.907(2)°, V = 1427.7(1) Å3, Z = 2, R 1 = 0.0546, and wR 2 = 0.1531. Complex II crystallizes in the monoclinic space group P21/c with unit cell dimensions a = 21.324(3), b = 16.821(2), c = 9.425(1) Å, β = 90.114(2)°, V = 3380.5(7) Å3, Z = 4, R 1 = 0.0693, and wR 2 = 0.1627. The Cu atom in I is in square planar coordination, and the Ni atom in II is in octahedral coordination. 相似文献
992.
Tetrazole Photoclick Chemistry: Reinvestigating Its Suitability as a Bioorthogonal Reaction and Potential Applications 下载免费PDF全文
Dr. Zhengqiu Li Linghui Qian Prof. Dr. Lin Li Dr. Jan C. Bernhammer Prof. Dr. Han Vinh Huynh Prof. Dr. Jun‐Seok Lee Prof. Dr. Shao Q. Yao 《Angewandte Chemie (International ed. in English)》2016,55(6):2002-2006
The bioorthogonality of tetrazole photoclick chemistry has been reassessed. Upon photolysis of a tetrazole, the highly reactive nitrile imine formed undergoes rapid nucleophilic reaction with a variety of nucleophiles present in a biological system, along with the expected cycloaddition with alkenes. The alternative use of the tetrazole photoclick reaction was thus explored: tetrazoles were incorporated into Bodipy and Acedan dyes, providing novel photo‐crosslinkers with one‐ and two‐photon fluorescence Turn‐ON properties that may be developed into protein‐detecting biosensors. Further introduction of these photo‐activatable, fluorogenic moieties into staurosporine resulted in the corresponding probes capable of photoinduced, no‐wash imaging of endogenous kinase activities in live mammalian cells. 相似文献
993.
Dual‐Targeting Nanovesicles for In Situ Intracellular Imaging of and Discrimination between Wild‐type and Mutant p53 下载免费PDF全文
Ruocan Qian Yue Cao Prof. Yi‐Tao Long 《Angewandte Chemie (International ed. in English)》2016,55(2):719-723
p53 is a tumor‐suppressor protein related to the cell cycle and programmed cell apoptosis. Herein, dual‐targeting nanovesicles are designed for in situ imaging of intracellular wild‐type p53 (WTp53) and mutant p53 (MUp53). Nanovesicle‐encapsulated plasmonic gold nanoparticles (AuNPs) were functionalized with consensus DNA duplexes, and a fluorescein isothiocyanate (FITC)‐marked anti‐MUp53 antibody was conjugated to the nanovesicle surface. After entering the cytoplasm, the released AuNPs aggregated through recognition of WTp53 and the double‐stranded DNA. The color changes of AuNPs were observed using dark‐field microscopy, which showed the intracellular WTp53 distribution. The MUp53 location was detected though the immunological recognition between FITC‐labeled anti‐MUp53 and MUp53. Thus, a one‐step incubation method for the in situ imaging of intracellular WTp53 and MUp53 was obtained; this was used to monitor the p53 level under a drug treatment. 相似文献
994.
Basic Physicochemical Properties of Polyethylene Glycol Coated Gold Nanoparticles that Determine Their Interaction with Cells 下载免费PDF全文
Dr. Pablo del Pino Fang Yang Dr. Beatriz Pelaz Dr. Qian Zhang Karsten Kantner Raimo Hartmann Dr. Natalia Martinez de Baroja Marta Gallego Marco Möller Dr. Bella B. Manshian Dr. Stefaan J. Soenen René Riedel Prof. Dr. Norbert Hampp Prof. Dr. Wolfgang J. Parak 《Angewandte Chemie (International ed. in English)》2016,55(18):5483-5487
A homologous nanoparticle library was synthesized in which gold nanoparticles were coated with polyethylene glycol, whereby the diameter of the gold cores, as well as the thickness of the shell of polyethylene glycol, was varied. Basic physicochemical parameters of this two‐dimensional nanoparticle library, such as size, ζ‐potential, hydrophilicity, elasticity, and catalytic activity ,were determined. Cell uptake of selected nanoparticles with equal size yet varying thickness of the polymer shell and their effect on basic structural and functional cell parameters was determined. Data indicates that thinner, more hydrophilic coatings, combined with the partial functionalization with quaternary ammonium cations, result in a more efficient uptake, which relates to significant effects on structural and functional cell parameters. 相似文献
995.
Synthesis,Crystal Structure,and Electrochemical Properties of a Simple Magnesium Electrolyte for Magnesium/Sulfur Batteries 下载免费PDF全文
Dr. Wanfei Li Shuang Cheng Jian Wang Dr. Yongcai Qiu Zhaozhao Zheng Dr. Hongzhen Lin Sanjay Nanda Qian Ma Yan Xu Dr. Fangmin Ye Dr. Meinan Liu Lisha Zhou Prof. Yuegang Zhang 《Angewandte Chemie (International ed. in English)》2016,55(22):6406-6410
Most simple magnesium salts tend to passivate the Mg metal surface too quickly to function as electrolytes for Mg batteries. In the present work, an electroactive salt [Mg(THF)6][AlCl4]2 was synthesized and structurally characterized. The Mg electrolyte based on this simple mononuclear salt showed a high Mg cycling efficiency, good anodic stability (2.5 V vs. Mg), and high ionic conductivity (8.5 mS cm?1). Magnesium/sulfur cells employing the as‐prepared electrolyte exhibited good cycling performance over 20 cycles in the range of 0.3–2.6 V, thus indicating an electrochemically reversible conversion of S to MgS without severe passivation of the Mg metal electrode surface. 相似文献
996.
Dr. Shuguang Yuan Dr. Qian Peng Prof. Krzysztof Palczewski Prof. Horst Vogel Prof. Slawomir Filipek 《Angewandte Chemie (International ed. in English)》2016,55(30):8661-8665
G‐protein‐coupled receptors (GPCRs) are involved in a wide range of physiological processes, and they have attracted considerable attention as important targets for developing new medicines. A central and largely unresolved question in drug discovery, which is especially relevant to GPCRs, concerns ligand selectivity: Why do certain molecules act as activators (agonists) whereas others, with nearly identical structures, act as blockers (antagonists) of GPCRs? To address this question, we employed all‐atom, long‐timescale molecular dynamics simulations to investigate how two diastereomers (epimers) of dihydrofuroaporphine bind to the serotonin 5‐HT1A receptor and exert opposite effects. By using molecular interaction fingerprints, we discovered that the agonist could mobilize nearby amino acid residues to act as molecular switches for the formation of a continuous water channel. In contrast, the antagonist epimer remained firmly stabilized in the binding pocket. 相似文献
997.
Synthesis,Photophysical and Electrochemical Properties,and Self‐assembly Behavior of Two Hexaazatriphenylene Derivatives: A Single Bond Makes a Big Difference 下载免费PDF全文
Cheng Qian Wei‐Hao Zhao Yuan Tian Prof. Guo‐Fang Jiang Dr. Tian‐Guang Zhan Prof. Xin Zhao 《化学:亚洲杂志》2016,11(6):839-843
A hexaazatriphenylene (HAT) derivative (compound 1 ) that bears four n‐octyl chains and two thienyl groups was designed and synthesized. Further light‐induced oxidation coupling reaction led to thienyl‐fused compound 2 . Their photophysical and electrochemical properties and self‐assembly behavior have been investigated by UV/Vis, fluorescence, and 1H NMR spectroscopies, cyclic voltammetry (CV), scanning electron microscopy (SEM), and powder X‐ray diffraction (PXRD). Although the difference in compounds 1 and 2 only lie in one single bond that connects the two thienyl segments, they displayed remarkably different properties, revealing an interesting structure–property relationship. 相似文献
998.
A Study of Different Doped Metal Cations on the Physicochemical Properties and Catalytic Activities of Ce20M1Ox (M=Zr,Cr, Mn,Fe, Co,Sn) Composite Oxides for Nitric Oxide Reduction by Carbon Monoxide 下载免费PDF全文
Changshun Deng Min Li Junning Qian Qun Hu Dr. Meina Huang Qingjin Lin Yongshun Ruan Dr. Lihui Dong Prof. Bin Li Prof. Minguang Fan 《化学:亚洲杂志》2016,11(15):2144-2156
This work is mainly focused on investigating the effects of different doped metal cations on the formation of Ce20M1Ox (M=Zr, Cr, Mn, Fe, Co, Sn) composite oxides and their physicochemical and catalytic properties for NO reduction by CO as a model reaction. The obtained samples were characterized by using N2 physisorption, X‐ray diffraction, laser Raman spectroscopy, UV/Vis diffuse reflectance spectroscopy, inductively coupled plasma atomic emission spectroscopy, X‐ray photoelectron spectroscopy, temperature‐programmed reduction by hydrogen and by oxygen (H2‐TPR and O2‐TPD), in situ diffuse reflectance infrared Fourier transform spectroscopy, and the NO+CO model reaction. The results imply that the introduction of Mx+ into the lattice of CeO2 increases the specific surface area and pore volume, especially for variable valence metal cations, and enhances the catalytic performance to a great extent. In this regard, increases in the oxygen vacancies, reduction properties, and chemisorbed O2? (and/or O?) species of these Ce20M1Ox composite oxides (M refers to variable valence metals) play significant roles in this reaction. Among the samples, Ce20Cr1Ox exhibited the best catalytic performance, mainly because it has the best reducibility and more chemisorbed oxygen, and significant reasons for these attributes may be closely related to favorable synergistic interactions of the vacancies and near‐surface Ce3+ and Cr3+. Finally, a possible reaction mechanism was tentatively proposed to understand the reactions. 相似文献
999.
Qian Ni Bing Chen Shaohua Dong Lei Tian Quan Bai 《Biomedical chromatography : BMC》2016,30(4):566-573
The core–shell structure Fe3O4/SiO2 magnetic microspheres were prepared by a sol–gel method, and immobiled with iminodiacetic acid (IDA) as metal ion affinity ligands for protein adsorption. The size, morphology, magnetic properties and surface modification of magnetic silica nanospheres were characterized by various modern analytical instruments. It was shown that the magnetic silica nanospheres exhibited superparamagnetism with saturation magnetization values of up to 58.1 emu/g. Three divalent metal ions, Cu2+, Ni2+ and Zn2+, were chelated on the Fe3O4@SiO2–IDA magnetic microspheres to adsorb lysozyme. The results indicated that Ni2+‐chelating magnetic microspheres had the maximum adsorption capacity for lysozyme of 51.0 mg/g, adsorption equilibrium could be achieved within 60 min and the adsorbed protein could be easily eluted. Furthermore, the synthesized Fe3O4@SiO2–IDA–Ni2+ magnetic microspheres were successfully applied for selective enrichment lysozyme from egg white and His‐tag recombinant Homer 1a from the inclusion extraction expressed in Escherichia coli. The result indicated that the magnetic microspheres showed unique characteristics of high selective separation behavior of protein mixture, low nonspecific adsorption, and easy handling. This demonstrates that the magnetic silica microspheres can be used efficiently in protein separation or purification and show great potential in the pretreatment of the biological sample. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
1000.
Zhixin Xu Prof. Jiulin Wang Prof. Jun Yang Xiaowei Miao Prof. Renjie Chen Ji Qian Rongrong Miao 《Angewandte Chemie (International ed. in English)》2016,55(35):10372-10375
The lithium–sulfur battery is regarded as one of the most promising candidates for lithium–metal batteries with high energy density. However, dendrite Li formation and low cycle efficiency of the Li anode as well as unstable sulfur based cathode still hinder its practical application. Herein a novel electrolyte (1 m LiODFB/EC‐DMC‐FEC) is designed not only to address the above problems of Li anode but also to match sulfur cathode perfectly, leading to extraordinary electrochemical performances. Using this electrolyte, lithium|lithium cells can cycle stably for above 2000 hours and the average Coulumbic efficiency reaches 98.8 %. Moreover, the Li–S battery delivers a reversible capacity of about 1400 mAh g?1sulfur with retention of 89 % for 1100 cycles at 1 C, and a capacity above 1100 mAh g?1sulfur at 10 C. The more advantages of this cell system are its outstanding cycle stability at 60 °C and no self‐discharge phenomena. 相似文献