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131.
含肟醚的新型三唑并嘧啶衍生物的合成及除草活性研究 总被引:1,自引:0,他引:1
2-巯基-5,7-二甲基-1,2,4-三唑并[1,5-a]嘧啶(6)与氯乙醛或氯丙酮反应生成5,7-二甲基-1,2,4-三唑并[1,5-a]嘧啶-2-硫丙酮(硫乙醛) (7). 中间体7与O-烷基(芳基)羟胺(5)反应得到目标化合物1-(5,7-二甲基-1,2,4三唑[1,5-a]嘧啶-2-硫)乙醛-O-烷基肟醚(9), 2-(5,7-二甲基-1,2,4三唑[1,5-a]嘧啶-2-硫)丙酮O-烷基肟醚(10). 初步生物活性测试结果表明部分化合物具有较好的除草活性. 相似文献
132.
Yan D Yin G Huang Z Li L Liao X Chen X Yao Y Hao B 《Langmuir : the ACS journal of surfaces and colloids》2011,27(21):13206-13211
Zinc oxide nanoparticles (NPs) with the size of ~100 nm were prepared via a facile biomineralization process in the template of silk fibroin (SF) peptide at room temperature. These ZnO NPs have shown the remarkable behavior of low toxicity to gram-positive bacteria (Staphylococcus aureus, Staphylococcus agalactiae), gram-negative bacteria (Escherichia coli), and eukaryotic cells (mouse L929 fibroblasts). Bacteriological testing indicated that ZnO NPs presented a 50% inhibitory effect on Streptococcus agalactiae at the concentrations of >100 mM, whereas at the same concentrations, the growth of Staphylococcus aureus and Escherichia coli were hardly inhibited. On the other hand, a remarkable proliferation of Staphylococcus aureus or Escherichia coli was observed at the concentrations of ZnO NPs <50 mM. Moreover, the cytotoxicity test demonstrated that ZnO NPs mineralized with SF peptide possessed a low toxicity to mouse L929 fibroblasts. The SF peptide coated on the surface of ZnO NPs permitted greater adhesion and consequently greater proliferation of mouse L929 fibroblasts. Besides, from TEM micrographs of the cell ultrastructure, endocytosis of NPs into the cytoplasm can be detected and the ultrastructure of the cell underwent few changes. The cell membrane retained integrity, euchromatin dispersed homogenously inside the cytoplasm, the mitochondrial architecture remained intact, and no intracellular vacuoles were observed. High-resolution transmission electron microscopy images and selected area electron diffraction patterns of ultrathin cell sections indicated that the crystal structure of NPs was not damaged by the organelle or cytoplasm. All these observations indicated that ZnO NPs mineralized with the SF peptide possess good cytocompatibility. 相似文献
133.
Lili Yu Xin Yan Hong Li Rui Qin Guangfu Luo Chengyong Xu Jiaxin Zheng Qihang Liu Jing Lu Zhengxiang Gao Xuefeng Wang 《Theoretical chemistry accounts》2011,130(2-3):353-359
We investigate the transport properties of few-nm-long single-walled carbon nanotube (SWCNT) p-n junctions for the first time by using ab initio quantum transport calculations. Unlike the previously reported few-??m-long SWCNT p-n junctions, which rectify positively, all the investigated ultrashort SWCNT p-n junctions show negative rectification effect, accompanied by negative differential resistance. 相似文献
134.
用红外光谱和差示扫描量热法(DSC)研究了具有钙钛矿型层结构标题配合物的固-固相变。在340K处发现一个新的相变。实验证明了结构相变与烷基铵链动力学和氢键有关。在374K的主相变主要来源于烷基铵链构象的有序-无序变化,该变化可能与NH_3极性头的重定向运动偶合。在高温相在烷基铵链中产生了GTG+GTG’和GG以及临近端甲基的TG结构,因而形成了构象完全无序态。 相似文献
135.
136.
137.
In this paper, we prove that a composition operator onH
p
(B) is Fredholm if and only if it is invertible if and only if its symbol is an automorphism onB, and give the representation of the spectra of a class of composition operators. In addition, using composition operator,
we discuss intertwining Toeplitz operators.
Supported by NNSF and PDSF 相似文献
138.
The structural, elastic and electronic properties of BaZnO2 under pressure are investigated by the plane wave pseudopotential density functional theory (DFT). The calculated lattice parameters and unit cell volume of BaZnO2 at the ground state are in good agreement with the available experimental data and other theoretical data. The pressure dependences of elastic constants Cij, bulk modulus B, shear modulus G, B/G, Poisson’ s ratio σ, Debye temperature Θ and aggregate acoustic velocities VP and VS are systematically investigated. It is shown that BaZnO2 maintains ductile properties under the applied pressures. Analysis for the calculated elastic constants has been made to reveal the mechanical stability and mechanical anisotropy of BaZnO2. At the ground state, the calculated compressional and shear wave velocities are 8.26 km/s and 1.81 km/s, respectively, and the Debye temperature Θ is 240.8 K. The pressure dependences of the density of states and the bonding property of BaZnO2 are also investigated. 相似文献
139.
Pingyuan Wang Jian Li Xue Jiang Zhiqing Liu Na Ye Youjun Xu Guangfu Yang Yechun Xu Ao Zhang 《Tetrahedron》2014
We have developed a palladium-catalyzed N-arylation of the biologically interesting, but synthetically rather challenging 2-arylaminobenzothiazoles bearing multiple functionalities. This protocol was successfully used to readily synthesize our initial PARP14 inhibitor followed by a limited structural optimization. A more potent PARP14 inhibitor with an IC50 value of 1.69 μM was identified, and the interaction was ascertained by the X-ray co-crystal structure of the catalytic domain of PARP14 in complex with compound 8. 相似文献
140.
The convergence of several Galerkin-Petrov methods, including polynomial collocation and analytic element collocation methods of Toeplitz operators on Dirichlet space, is established. In particular, it is shown that such methods converge if the basis and test function own certain circular symmetry. 相似文献