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41.
Jin Luo Shu Li Qiongwen Kang Yi Sun 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):1180-1186
AbstractSixteen novel 3-methylthio-5-substituted benzamido-6-arylamino-1-phenyl-1H-pyrazolo[3,4-d]pyrimidin-4 (5H)-one derivatives (4a–p) were successfully synthesized from iminophosphoranes, aryl isocyanate, and substituted benzoylhydrazine. The structures of the title compounds were elucidated by FT-IR, 1H NMR, 13C NMR, and HRMS. Herbicidal activity of the compounds 4a–p against Brassica napus (rape), Echinochloa crusgalli (barnyard grass), Cucumis sativus (cucumber), and Triticum aestivum (wheat) were determined. The results showed that 5-(2-chlorobenzamido)-6-phenylamino-3-methylthio-1-phenyl-1H-pyrazolo[3,4-d]pyrimidin-4 (5H)-one (4c) displayed remarkable inhibition activity against the stalk and root of rape with 100% inhibition rate at the dosages of 10?mg/L and 100?mg/L, and 5-(4-nitrobenzamido)-6-phenylamino-3-methylthio-1-phenyl-1H-pyrazolo[3,4-d]pyrimidin-4 (5H) -one (4d) exhibited excellent activity against the stalk and root of barnyard grass with 100% inhibition rate at the same dosages. 相似文献
42.
This article presents an original work aimed at rationally designing molecularly imprinted polymer (MIP) toward a high specific adsorbent. Assembling with cobalt as the pivot, the MIP was prepared by coordinating polymerizable monomers around an inducible template. The use of pivot obviously plays a positive role on increasing the specificity of MIP, so as to adsorb more for the template and less for its analogue. Related studies indicate that these may be a result of increasing specific interaction, which makes the MIP capable of recognizing the imprint species. Further information from thermodynamic analysis reveals that the increasing specific interaction, in logic, can be due to a higher fidelity of imprint, which specifically allures the template to bind. 相似文献
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44.
Yan Yang Liu-Ting Yan Xu-Jian Luo Rong-Huan Qin Wen-Gui Duan 《Supramolecular chemistry》2013,25(11):810-818
Three novel coordination polymers, [Co(NH2-Aip)(H2Bibim)] n (1), [Co(NH2-Aip)(HBibimop)] n √ nH2O (2) and [Mn(NH2-Aip) √ H2O] n √ 2nH2O (3) with NH2-Aip and similar benzimidazole derivative ligands (NH2-Aip = 5-aminoisophthalic acid, H2Bibim = 2,2′-bibenzimidazole and HBibimop = 1,3-bis(benzimidazol-2-yl)-2-oxapropane), have been synthesised under hydrothermal conditions and structurally characterised by single-crystal X-ray diffraction analysis, elemental analysis and IR spectroscopy. 5-Aminoisophthalic acid ligand adopts μ2-, μ3- and μ4-bridge coordination fashion and benzimidazole derivatives exist as terminal- and bridge-mode in complexes 1–3. The intricate hydrogen bonds and π–π stacking interactions in supramolecular framework are discussed. Using the combination of ultraviolet–visible absorption titration and fluorescence spectra, the experimental results show that complexes 1 and 2 bind to DNA in an intercalative mode and their DNA-binding constants (K b ) are also found. 相似文献
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46.
2β,3α-Dihydroxyurs-12-en-28-oic acid(6) is a naturally occurring diastereoisomer of corosolic acid with glycogen phosphorylase inhibitory activity.A new strategy for the semi-synthesis of 6 was developed.Using the commercially available ursolic acid(1) as the starting materials,6 was synthesized through five facile reactions with a high stereoselectivity and an overall yield of 47.3%.The structure of 6 was confirmed by optical rotation.ESI-MS,1H NMR and 13C NMR data. 相似文献
47.
Wangping Wu Zhaofeng Chen Binbin Li Xiangna Cong Qing Chen 《Russian Journal of Electrochemistry》2013,49(1):76-80
In this paper, a platinum coating was deposited on titanium alloy substrate by a double glow plasma. Phase and microstructure of platinum coating were examined by X-ray diffraction and scanning electron microscopy, respectively. The microhardness of the coating was estimated by nanoindentation instrument. The adhesive force between the coating and the substrate was performed with scratch tester. The electrochemical behavior of the platinum coating in 3.5 wt % sodium chloride solution was investigated by potentiodynamic polarization. The results indicated that an adherent platinum coating could be successfully obtained on titanium alloy substrates. Compared with the titanium alloy substrate, the platinum coating had a relative low corrosion current density and high corrosion potential. It indicated that the platinum coating had a better corrosion resistance than the titanium alloy substrate. 相似文献
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49.
A small library of isocoumarin derivatives has been synthesized via K2CO3-catalyzed domino reactions of 2-carboxybenzaldehyde and ω-bromoacetophenones under microwave irradiation (MW). This strategy offers a simple, environmentally acceptable route to synthesize isocoumarin derivatives in moderate to excellent yields. All new compounds were characterized by 1H NMR, 13C NMR, infrared, and high-resolution mass spectroscopic techniques. 相似文献
50.
A green, efficient method for the synthesis of various 2-aryl-benzimidazoles in the presence of hypervalent iodine as the oxidant at room temperature under solvent-free conditions is reported. The salient features of this method include mild conditions, short reaction times (3–5 min), excellent yields, and simple procedure. 相似文献