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771.
Hui-Lu Wu Jing-Kun Yuan Ying Bai Fei Jia Bin Liu Fan Kou Jin Kong 《Transition Metal Chemistry》2011,36(8):819-827
Bis(N-allylbenzimidazol-2-ylmethyl)benzylamine (babb) and two of its complexes, [Cu(babb)(pic)2]·H2O (1) and [Co(babb)2](pic)2 (2) (pic = picrate), have been synthesized and characterized by physico-chemical and spectroscopic methods. Single crystal X-ray
diffraction revealed that the two complexes have similar distorted octahedral structures, but the degree of distortion and
the coordinated atoms are different. The DNA-binding properties of the free ligand and its two complexes have been investigated
by electronic absorption, fluorescence, and viscosity measurements. The results suggest that all three compounds bind to DNA
via an intercalative binding mode, and their binding affinity for DNA follows the order 2 > 1 > ligand. Additionally, both complexes exhibited potential antioxidant properties in in vitro studies, and complex 1 was the more effective. 相似文献
772.
Four stereoisomers of Phytophthora mating hormone α2 were synthesized using both enantiomers of citronellol as starting materials. The absolute configuration of the natural product was determined to be 7S,11R,15R by oospore-inducing assays of the synthetic isomers. A concise synthetic procedure of α1 was also established using a common synthetic intermediate of α2. 相似文献
773.
Josef Buršík Ivo Drbohlav Zdeněk Frait Karel Kní?ek Radomír Ku?el Karel Kou?il 《Journal of solid state chemistry》2011,184(11):3085-3094
Thin films of SrFe12O19 (SrM) were prepared from a solution of iron and strontium alkoxides through the chemical solution deposition method on both amorphous (glassy SiO2), and single crystal substrates (Si(100), Si(111), Ag(111), Al2O3(001), MgO(111), MgAl2O4(111), SrTiO3(111)) substrates. The process of crystallization was investigated by means of powder diffraction, atomic force microscopy and scanning electron microscopy. Magnetization measurements, ferromagnetic and nuclear magnetic resonance were used for evaluation of anisotropy in the films. Whilst amorphous substrates enabled growth of randomly oriented SrM phase, use of single crystal substrates resulted in samples with different degree of oriented growth. The most pronounced oriented growth was observed on SrTiO3(111). A detailed inspection revealed that growth of SrM phase starts through the breakup of initially continuous film into isolated grains with expressive shape anisotropy and hexagonal habit. A continuous film with epitaxial relations to the substrate was produced by repeating recoating and annealing. 相似文献
774.
Tetranuclear [Ni(4)(Hpzaox)(2)(pzaox)(2)(py)(4)](ClO(4))(2)·2py (1), [Ni(4)(Hpzaox)(2)(pzaox)(2)(py)(4)](NO(3))(2)·4py (2), and two-dimensional (2D) [Ni(4)(Hpzaox)(2)(pzaox)(2)(H(2)O)(2)](NO(3))(2)·2H(2)O (3) are prepared via the reaction of NiX(2)·6H(2)O and pyrazine-2-amidoxime (H(2)pzaox). All compounds contain [Ni(4)(Hpzaox)(2)(pzaox)(2)](2+) fragments, which assemble to form a tetranuclear or polymeric network. Magnetic studies show that the tetranuclear compounds display usual ferromagnetic coupling via the oxime N-O bridges, and the 2D compound displays unusual antiferromagnetic behavior. 相似文献
775.
Wu H Kou F Jia F Liu B Yuan J Bai Y 《Journal of photochemistry and photobiology. B, Biology》2011,105(3):190-197
A six-coordinate copper(II) complex with the ligand 1,3-bis(1-methylbenzimidazol-2-yl)-2-oxopropane (Meobb), with composition [Cu(Meobb)(2)](NO(3))(2)·2CH(3)OH, has been synthesized and characterized by elemental analysis, electrical conductivities, IR, UV-Vis spectral measurements. A study of the electro-chemistry of the copper(II) complex was carried out by using cyclic voltammetry. The molecular structures of the ligand Meobb and the Cu(II) complex were determined by X-ray crystal diffraction. The DNA-binding modes of the ligand and the complex were investigated by electronic absorption titration, ethidium bromide-DNA displacement experiments and viscosity measurements. The experimental evidence indicated the compounds interact with calf thymus DNA through intercalation. Additionally, the Cu(II) complex exhibited potential antioxidant properties in in vitro studies. 相似文献
776.
Little Higgs models with T-parity predict the existence of the new sources of flavor-violating interactions between SM fermions
and mirror fermions. We analyze corrections to the anomalous magnetic dipole moments of leptons from Bar-Zee-type diagrams
in the LHT model. We find that the contributions of the LHT model are not sensitive to the new flavor mixing matrix and the
value is of the order of 10−11. 相似文献
777.
Bing Zhang Hui‐Zhong Kou Yi He Hong‐Gen Wang Ai‐Li Cui 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(7):m341-m342
A new polymeric copper complex, viz.catena‐poly[[[μ‐N,N′‐bis(3‐aminopropyl)oxamidato‐κ6N,N′,O:N′′,N′′′,O′]dicopper(II)]‐di‐μ‐dicyanamido‐1:1′κ2N1:N5;2:2′κ2N1:N5], [Cu2(C8H16N4O2)(C2N3)2]n or [Cu(oxpn)0.5{N(CN)2}]n [where H2oxpn is N,N′‐bis(3‐aminopropyl)oxamide], has been synthesized by the reaction of Cu(oxpn), [Cu(ClO4)2]·6H2O and NaN3. In the crystal structure, the Cu atom is five‐coordinate and has a square‐pyrimidal (SP) configuration. In the polymer, dicyanamide (dca−) groups link CuII cations in a μ‐1,5‐bridging mode, generating novel ladders in which each step is composed of dimeric [Cu2(oxpn)]2+ cations. Abundant hydrogen bonds connect the polymer ladders into a two‐dimensional network structure. 相似文献
778.
一氧化氮(NO)是一种很好的血小板黏附或活化的抑制剂,同时也是很有效的抗平滑肌细胞增生剂。可释放NO的聚合物材料显示出较好的抗血栓形成及抑制细胞增生的性能。本文综述了可释放NO聚合物材料的制备方法及其近年来在生物医疗器械中的应用。用来制备可释放NO聚合物材料的NO供体主要有两大类,一类是亲核NO供体N-diazeniumdiolates,另一类是S-亚硝基硫醇(RENOs)。制备可释放NO聚合物材料的方法主要有3种:(1)通过物理掺杂的方式将小分子的NO供体分散到聚合物材料中;(2)对聚合物材料的填料微粒进行化学改性,得到可释放NO的填料粒子,再将其填充到聚合物材料中;(3)通过共价键将可释放NO的基团连接到聚合物主链及侧链上。所得到的可释放NO聚合物材料在血管内传感器、体外血液循环电路和体内移植血管等生物医疗器械中有广泛的应用。 相似文献
779.
780.
Jin Jie Tian Xu Tao Yi Kou Xianli Mi Yuanhao Xu Xiaokang Yang Huifeng 《Journal of Solid State Electrochemistry》2023,27(9):2309-2321
Journal of Solid State Electrochemistry - CrMoCN coatings with different carbon contents are prepared on 316L stainless steel substrates by closed-field unbalanced magnetron sputtering. The... 相似文献