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991.
Guang-Qi Jiang Ruo Wang Li-Li Long Tao Sun Zai-chang Yang Yun-Qian Zhang 《Journal of Coordination Chemistry》2016,69(4):678-686
Four new complexes have been prepared and characterized from reaction of the tetrapodal Schiff base ligand 1,1,1,1-tetrakis[(3-methoxysalicylaldimino)methyl]methane (H4L) with Cu(II), Ni(II) and Cd(II). X-ray diffraction experiments revealed that 1 ([Cu2L·2H2O]·H2O) and 2 ([Cu2L·2CH3OH]·3H2O) are dinuclear complexes, with the same tetragonal pyramidal coordination geometries around their Cu(II) ions. Complex 3 ([Ni2L]·2H2O) is dinuclear with two square planar Ni(II) ions coordinated to two pairs of the pendant branches of H4L. Complex 4 ([Cd3(HL)2]·3H2O) is a linear trinuclear species with three Cd(II) ions, which were intermolecularly coordinated to three pendant branches of two H4L ligands via an uncommon intermolecular phenoxo oxygen face-sharing mode. The in vitro antimicrobial activities of H4L and its complexes were evaluated against four micro-organisms (Colibacillus, Staphylococcus aureus, Pseudomonas aeruginosa, and Bacillus subtilis) using the tube-dilution method. The results revealed that 3 showed good inhibitory activity against the Gram-positive bacteria S. aureus and B. subtilis with MIC values of 62.5 and 31.0 μg mL, respectively. 相似文献
992.
Yin-Di Zhu Jing-Yi Zhang Peng-Fei Li Hai-Feng Wu Nai-Liang Zhu Hai Jiang 《Natural product research》2016,30(9):1075-1080
Two new abietane diterpenoid glycosides, named clinopoditerpenes B (1) and C (2), were isolated from Clinopodium chinese. The structures of the new compounds were determined on the basis of extensive spectral analysis. Compound 1 exhibited cardioprotective effect against H2O2-induced apoptosis in H9c2 cells. 相似文献
993.
A series of compounds possessing 2-(3-phenyl)ureidothiazol-4-formamide derivatives with a 2-ureidothiazole scaffold were designed and synthesized. Some compounds demonstrated inhibition of cell proliferation against both MDA-MB-231 and HepG2 cell lines using Sorafenib as the positive control. Compounds 6i showed a good to moderate inhibition on VEGFR-2 and PI3Kα which was proved by further molecular docking study. This study suggests that compound 6i is a potential dual inhibitor of VEGFR-2 and PI3Kα and is applicable for further investigation. 相似文献
994.
Yan-Peng Gao Le Guo Yan-Hua Lv Wei Dong Min Jia 《Journal of Coordination Chemistry》2016,69(24):3745-3761
We have synthesized a series of metal–organic coordination frameworks under solvothermal conditions, formulated as [Cu(L)(phen)](1), [Co2(L)2(bib)]·CH3OH(2), [Co(L)(btmb)0.5](3), [Zn(L)(bib)]·2H2O(4), [Cu(L)(bib)]·DMF(5), and [Mn4(L)4(bimb)(CH3OH)](6) based on a flexible multicarboxylic bridging ligand 4,4′-methylenebis(oxy)-dibenzoic acid (H2L) and flexible N-donor ligands 1,4-bis (1H-imidazol-1-yl)-butane (bib), 1,4-bis(1H-1,2,4-triazol- 1-ylmethyl)benzene (btmb), and 1,4-bis(1H-imidazol-1-ylmethyl)benzene (bimb). The structures of the frameworks have been determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, IR spectra, and thermogravimetric analyses. The crystal structure determinations reveal that 1 has a 1-D Z-shape chain. Compounds 2 and 3 are 2-D twofold parallel interpenetrating 4-connected net with the Schläfli symbol {44·62}. Compound 4 is a 2-D threefold parallel interpenetrating 4-connected nets with the Schläfli symbol {44·62}. Compound 5 is 3-D 4-connected net with the Schläfli symbol {65·8}. Compound 6 is characterized by a three-dimensional framework with one-dimensional homogeneous Mn-carboxylate chain. We found that flexible carboxylate ligands have different coordination modes under different synthetic conditions. The flexible skeleton of ligands and the coordination angle between the ligand and the metal ion is described. The luminescence and thermogravimetric properties of these compounds have been investigated. 相似文献
995.
Two new nimbolinin‐type limonoids, 12‐ethoxynimbolinins E and F ( 1 and 2 , resp.), together with seven known analogues, 1α‐benzoyloxy‐3α‐acetoxyl‐7α‐hydroxy‐12β‐ethoxynimbolinin ( 3 ), nimbolinin B ( 4 ), meliatoosenin L ( 5 ), 14,15‐deoxy‐11‐oxohavanensin 3,12‐diacetate ( 6 ), 12α‐hydroxymeliatoosenin ( 7 ), toosendansin A ( 8 ), and toosendansin C ( 9 ), were isolated from the fruits of Melia toosendan. The structures of these compounds were elucidated by spectroscopic analysis. All the compounds were evaluated for their cytotoxicity against five tumor cell lines. 相似文献
996.
金属有机骨架(MOFs)材料是一种相对新型的多孔材料,由于其结构的多样性、可设计性、可剪裁性以及超高的比表面积,近年来吸引了广泛的研究兴趣,并在很多领域展现了潜在的应用前景.特别是在催化方面的应用更受到了强烈的关注.本文的前两部分主要以催化活性位点的来源进行分类,包括配位不饱和金属中心、功能性有机配体、化学修饰接入功能位点以及嵌入在MOFs孔内的金属配合物或金属纳米颗粒等,总结了近几年来MOFs及其复合材料在多相催化方向取得的一些进展.同时在后面两部分也简要地介绍了MOFs在光催化及以MOFs为模板构筑的多孔纳米材料在催化(特别是电催化)方面的一些应用.最后,对MOFs在催化方面的应用前景做了展望. 相似文献
997.
Pengjuan Ni Yujing Sun Haichao Dai Shu Jiang Wangdong Lu Yilin Wang Zhen Li Zhuang Li 《Mikrochimica acta》2016,183(9):2589-2595
We describe a sensitive and selective colorimetric method for the determination of the activity of the enzyme acetylcholinesterase (AChE) and its inhibitors. Detection is based on the fact that acetylthiocholine iodide (ATCI) catalyzes the oxidation of the substrate 3,3′,5,5′-tetramethylbenzidine (TMB) by H2O2 to form a blue product (ox-TMB) with an absorption peak at 652 nm, but that oxidation is suppressed if ACTI previously is hydrolyzed by AChE to form thiocholine which decolorizes ox-TMB. In the presence of inhibitor, the activity of AChE is inhibited, thereby inducing the recovery of the blue coloration. Based on these findings, a highly sensitive method is developed for the determination of AChE and its inhibitors. The assay only requires mixing of buffer, solutions of ATCI, TMB, H2O2 and a sample containing AChE and photometric measurement. It works in the 0.05 to 5 mU?mL?1 enzyme activity range and has a detection limit as low as 30 μU?mL?1. The inhibitor neostigmine causes 50 % enzyme inhibition in 14.5 nM concentration. This analytical system has a wide scope in that it may be applied to the determination of the activity of various other hydrolases with proper substrates. 相似文献
998.
999.
1000.
Adopting LB film method, an arachidic acid (AA)/PEDOT multilayer LB film was chosen, and polymerized EDOT monomers in hydrophilic group of LB to prepare arachidic acid (AA)/PEDOT multilayer LB film. UV‐Vis, FT‐IR and XPS analyses implied that EDOT was effectively polymerized in film, and thus PEDOT conducting polymer was produced. Analyses of XRR and SIMS indicated that film had a well‐arranged lamella structure, and further research showed that polymerization of EDOT in AA film destroyed the orderliness of the original LB film. This phenomenon could be related to the destructive effect of polymerization on layered structure. We used four‐point probe and semiconductor instrument to study the conductivity property of the film, and observed that the conductivity of AA/PEDOT film had sudden changes with the processing time of changes in effective conduction network. That was caused by "permeability" in conducting channel of multilayer film. The test results also indicated that the conductivity of AA/PEDOT film was obviously better than that of spin‐coating PEDOT/PSS film or that of ODA‐SA/PEDOT‐PSS film, which was due to the higher π structure of PEDOT structure and ordered film structure. 相似文献