排序方式: 共有24条查询结果,搜索用时 15 毫秒
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ZHOU Cheng-He Juan F.Miravet M.Isabel Burguete Santiago V.Luis BAI Xue YUAN Yong 《有机化学》2004,24(Z1):380
Polynitrogen receptors such as bis-histidine peptides possess strong ability to bind metals, which play much important roles in medicinal, bioinorganic, bioorganic, biomimetic and supramolecular chemistry. In order to investigate the interaction of these hosts with a variety of neutral, cationic and anionic guests, several techniques, for example, NMR,potentiometric tirations and monocrystal X-ray diffraction have been employed. Among them NMR is a powerful technique for unraveling the structure of polynitrogen receptors as long as they are in solution where the rapid tumbling of molecules averages out the anisotropies such as chemical shift and dipole-dipole interactions. General 1H NMR approach has been widely used for the study of host-guest interaction, but it is difficult for the accurate measurement in complexes structures, particularly metal complexes structures in which how the polynitrogen receptors bind metal, and which nitrogen binds metal and so on. 相似文献
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Lin Xiao Tao-Tao Lang Ying Jiang Dr. Zhong-Lin Zang Prof. Cheng-He Zhou Prof. Dr. Gui-Xin Cai 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(10):3278-3283
We report a challenging copper-catalyzed Cformyl−H arylation of salicylaldehydes with arylboronic acids that involves unique salicylaldehydic copper species that differ from reported salicylaldehydic rhodacycles and palladacycles. This protocol has high chemoselectivity for the Cformyl−H bond compared to the phenolic O−H bond involving copper catalysis under high reaction temperatures. This approach is compatible with a wide range of salicylaldehyde and arylboronic acid substrates, including estrone and carbazole derivatives, which leads to the corresponding arylation products. Mechanistic studies show that the 2-hydroxy group of the salicylaldehyde substrate triggers the formation of salicylaldehydic copper complexes through a CuI/CuII/CuIII catalytic cycle. 相似文献
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A series of novel N-(1-(3-chlorophenyl)-3-aryl-3-oxopropyl)-2-(4-nitrophenyl) acetamides were synthesized using p-nitrophenylacetonitrile, m-chlorobenzaldehyde, and aryl methyl ketones as starting materials and trifluoroacetic acid (TFA) as catalyst. This realized an improved Dakin–West reaction in which p-nitrophenylacetonitrile was involved. The chemical structures of up to 15 target molecules were characterized by 1H NMR, 13C NMR, and high-resolution mass spectrometry. This method provides a facile synthetic protocol under more moderate reaction conditions, smaller dosage (0.40 mol%) and hence lower cost of catalyst, and simpler posttreatment in comparison to other known methods. A reaction mechanism is proposed in which hydroxyacetophenone is first catalytically converted into the corresponding acetoxyacetophenone prior to be involved in the subsequent Dakin–West reaction that eventually leads to hydroxyl-acetylated target compounds.
[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.] 相似文献
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ZHOU Cheng-He LIU Qiang Juan F. Miravet M. Isabel Burguete Santiago V. Luis 《有机化学》2003,23(Z1):415-415
A series of novel histidine-based open-chain dipeptides, polypeptides and cyclopeptides with anti-HIV potential were designed and synthesized from commercial histidine (Scheme 1). 相似文献
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噻吩并噻吩的合成研究 总被引:1,自引:0,他引:1
噻吩并噻吩自1886年以来一直是化学研究的对象, 综述了经典稠合噻吩并噻吩的合成方法. 对一般的合成方法及原始地制备某一类特定化合物的方法都作了简要讨论. 相似文献
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送气成像(gas puff imaging,GPI)是一种重要的研究边缘辐射诊断手段.分析了送气(gas puffing,GP)的原子分子过程,指出气体辐射的主要成分是Hα线,出现在边缘区域,并给出其强度和位置的表达式.介绍HL-2A托卡马克上GPI成像系统的改进和实验布置.从成像的角度获得了GP实验中氢气在等离子体空间的辐射图形,观察结果证实上述分析.在放电开始阶段,氢原子可以穿越待建立的完全等离子体区并形成长条形的辐射亮区.一般的GP加料中,CCD图片与控制信号,以及其他诊断结果相符合.在等离子体边缘区域强场侧(HFS)和弱场侧(LFS)都观察到很强的Hα线辐射.
关键词:
送气
CCD成像
Hα线 相似文献
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ZHOU Cheng-He WU Jun YUAN Yong BAI Xue Juan F.Miravet M.Isabel Burguete Santiago V.Luis 《有机化学》2004,24(Z1):377
A novel tetra-histidine cyclopeptide was prepared through multi-step reactions from histidine and naphthalene diamine (Scheme 1). All new compounds were characterized by 1H, 13C, 1H-15N and 1H-13C HETCOR spectra. 相似文献
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Jie Kang Vijai Kumar Reddy Tangadanchu Lavanya Gopala Wei-Wei Gao Yu Cheng Han-Bo Liu Rong-Xia Geng Shuo Li Cheng-He Zhou 《中国化学快报》2017,28(7):1369-1374
A series of novel naphthalimide-derived metronidazoles as new type of antimicrobial agents were for the first time designed, synthesized and characterized by NMR, IR and HRMS spectra. Experimental results revealed that most of them displayed moderate to good antibacterial activity towards Gram-positive and negative bacteria. Especially, compound 7b was able to not only exhibit effective inhibition towards the growth of P. vulgaris (MIC=0.002 μmol/mL) and S. dysenteriae (MIC=0.01 μmol/mL), but also have rapidly killing effect and prevent the development of bacterial resistance. Further research revealed that the highly active molecule 7b could not only intercalate into calf thymus DNA to form a steady supramolecular complex and thus might block DNA replication to exert the powerful bioactivities, but also be effectively transported by human serum albumin (HSA) via the formation of the 1:1 supramolecular complex, in which hydrogen bonds and hydrophobic effect played important roles in the association of compound 7b with HSA. Molecular docking indicated that the supramolecular interactions between 7b and topoisomerase Ⅱ were driven by hydrogen bonds. 相似文献
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