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间苯二酚杯芳烃是超分子化学的第3代主体分子。介绍了间苯二酚杯芳烃的结构、衍生化途径及其衍生物的用途。 相似文献
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为深入开展杯芳烃为骨架的超分子拓扑结构的组装和性能,开展了间苯二酚杯芳烃八取代吡啶酰胺的合成和分子结构的研究。 以四丙基、四己基和四庚基间苯二酚杯芳烃为原料,使用α-氯乙酸甲酯实现O-烃基化,后者在无溶剂条件下与2-氨甲基吡啶反应实现酰胺化,制备了烷基间苯二酚杯芳烃八[N-(2-吡啶甲基)乙酰胺]衍生物。 用X衍射方法测定了四丙基间苯二酚杯芳烃八乙酸甲酯、四丙基以及四己基间苯二酚杯芳烃八[N-(2-吡啶甲基)乙酰胺]的单晶分子结构。 在晶体中,间苯二酚杯芳烃都以全顺式构型存在,在成环的四个间苯二酚单元中,1,3-位的两个间苯二酚单元处于近直立构象,2,4-位的另两个间苯二酚单元处于近平伏构象,而4个烷基皆处于分子的下缘,8个乙酰胺支链伸向分子的外围。 相似文献
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杯芳烃是由苯酚单元通过亚甲基连接而成的空腔型分子,具有衍生位点多,构象丰富等特点,被称为第三代主体分子。在分子层次,依手性因素的结构特点不同,可将手性杯芳烃分为具有手性亚单元的杯芳烃、固有手性杯芳烃和桥手性杯芳烃。在超分子层次,杯芳烃自身或杯芳烃与其他分子或离子在溶液中、晶态中或二维表面可通过非共价键力形成多种拓扑结构的纳米手性聚集体。研究手性杯芳烃和基于杯芳烃的超分子手性组装体的合成、结构和性能,不仅在理解手性起源、手性结构等方面具有理论意义,而且有望获得以分子识别为基础的手性传感器、手性催化剂、手性分离材料、手性载体和手性纳米材料。本文综述近十年来有代表性的分子手性杯芳烃和以杯芳烃为组分的超分子手性聚集体的设计、合成、结构和功能。着重展示杯芳烃骨架在形成新颖分子手性和超分子手性上的优势,以及杯芳烃单元在实现特定功能如手性识别时发挥的作用。相信随着杯芳烃合成技术和杯芳烃超分子设计的发展,必将进一步发挥杯芳烃的结构优势,涌现出更多性能优异的手性杯芳烃功能分子和超分子手性杯芳烃功能材料。 相似文献
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本文介绍了杂杯芳烃和冠芳烃的研究起源,总结了杂杯芳烃和冠芳烃的设计与合成、构象和大环空腔结构特征,展示了杂杯芳烃和冠芳烃的分子识别和组装性质,概述了杂杯芳烃和冠芳烃在功能材料的制备中的应用,展望了大环超分子化学未来的发展方向。 相似文献
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磺化杯芳烃具有非常强的分子键合能力, 被广泛用于水相超分子自组装研究. 介绍了磺化杯芳烃与客体阳离子形成超分子组装体的主要驱动力和形貌调控因素; 总结了包括主体诱导客体聚集、客体诱导主体聚集及主客体共组装在内的三种主要聚集模式; 并展望了其在刺激响应材料、药物传递载体、多功能超分子平台和超分子催化等领域的重要应用前景. 相似文献
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Herrmann A 《Angewandte Chemie (International ed. in English)》2007,46(31):5836-5863
Volatile organic compounds serve in nature as semiochemicals for communication between species, and are often used as flavors and fragrances in our everyday life. The quite limited longevity of olfactive perception has led to the development of pro-perfumes or pro-fragrances--ideally nonvolatile and odorless fragrance precursors which release the active volatiles by bond cleavage. Only a limited amount of reaction conditions, such as hydrolysis, temperature changes, as well as the action of light, oxygen, enzymes, or microorganisms, can be used to liberate the many different chemical functionalities. This Review describes the controlled chemical release of fragrances and discusses additional challenges such as precursor stability during product storage as well as some aspects concerning toxicity and biodegradability. As the same systems can be applied in different areas of research, the scope of this Review covers fragrance delivery as well as the controlled release of volatiles in general. 相似文献
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《印度化学会志》2023,100(1):100818
In the present paper, the heat generating and/or absorption as well as thermo-diffusion on the unsteady free convection MHD gyrating flow of radiation and chemical reactive second grade fluid past an unbounded perpendicular plate during absorbent medium have been discussed. Here, it is assumed that, the confining plate has the ramped wall temperature with ramped surface concentration and isothermal temperature with ramped surface concentration. The analytical solutions for the governing equations are found by utilization of Laplace transformation methodology. The velocity, temperature and concentration profiles are analyzed with quite few figures. It is determined that, velocity, temperature and concentration distribution sketches in case of ramped temperature as well as ramped surface concentration are not as much of as those of isothermal temperature as well as ramped surface concentration. In addition to the idioms of skin friction, Nusselt number as well as Sherwood number are achieved and characterized numerically with tabular format. 相似文献
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Entesar A. Hassan Salem E. Zayed 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):300-323
Abstract Organic dithiocarbamates have received great attention due to their interesting chemistry and wide utility as radical precursors and intermediates in organic synthesis. They also have found many of applications, that is, in agriculture and medicine. They are in use as pesticides, as well as in the rubber industries as vulcanization accelerators; and as antioxidants. Because they exhibit strong metal-binding capacity, they can act as in inhibitors of enzymes and have a profound effect on biological systems. Moreover, they have found application in the treatment of cancer and HIV. 相似文献
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Aptamers: molecular tools for analytical applications 总被引:3,自引:0,他引:3
Mairal T Ozalp VC Lozano Sánchez P Mir M Katakis I O'Sullivan CK 《Analytical and bioanalytical chemistry》2008,390(4):989-1007
Aptamers are artificial nucleic acid ligands, specifically generated against certain targets, such as amino acids, drugs,
proteins or other molecules. In nature they exist as a nucleic acid based genetic regulatory element called a riboswitch.
For generation of artificial ligands, they are isolated from combinatorial libraries of synthetic nucleic acid by exponential
enrichment, via an in vitro iterative process of adsorption, recovery and reamplification known as systematic evolution of
ligands by exponential enrichment (SELEX). Thanks to their unique characteristics and chemical structure, aptamers offer themselves
as ideal candidates for use in analytical devices and techniques. Recent progress in the aptamer selection and incorporation
of aptamers into molecular beacon structures will ensure the application of aptamers for functional and quantitative proteomics
and high-throughput screening for drug discovery, as well as in various analytical applications. The properties of aptamers
as well as recent developments in improved, time-efficient methods for their selection and stabilization are outlined. The
use of these powerful molecular tools for analysis and the advantages they offer over existing affinity biocomponents are
discussed. Finally the evolving use of aptamers in specific analytical applications such as chromatography, ELISA-type assays,
biosensors and affinity PCR as well as current avenues of research and future perspectives conclude this review. 相似文献
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The weak, noncovalent interactions among molecules at long range and as close as van der Waals contact form a crucial contemporary frontier for chemical physics, one with many challenges for experimental as well as theoretical investigation. Certain of these challenges have been met in the last two decades, but as recognition of the complexity of phenomena governed or affected by weak interaction has grown, new challenges have arisen. We discuss a number of these challenges in the context of recent developments and progress, highlighting both disparate objectives of theory and experiment in this area as well as their crucial interplay. 相似文献
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Kirschning A Solodenko W Mennecke K 《Chemistry (Weinheim an der Bergstrasse, Germany)》2006,12(23):5972-5990
The concepts article describes enabling techniques (solid-phase assisted synthesis, new reactor design, microwave irradiation and new solvents) in organic chemistry and emphasizes the combination of several of them for creating new synthetic technology platforms. Particular focus is put on the combination of immobilized catalysts as well as biocatalysts with continuous flow processes. In this context, the PASSflow continuous flow technique fulfils both chemical as well as chemical engineering requirements. It combines reactor design with optimized, monolithic solid phases as well as reversible immobilization techniques for performing small as well as large scale synthesis with heterogenized catalysts under continuous flow conditions. 相似文献
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研制了一种新型全息用光致聚合物材料,其成膜树脂为胺固化环氧体系,全息记录组分为光引发自由基聚合体系.用新合成的高效光敏染料DEAMC做光敏剂,通过配方调整,制备了一系列的样片,以457 nm的蓝光为记录光,632.8 nm的红光为探针光,研究了样片的衍射效率、灵敏度、折射率调制度等全息性能.结果表明,通过调整材料的配方组成、各组分的含量及样片的膜厚等因素,可以优化样片的全息性能.对样片的信噪比损失(LSNR)测试结果表明,在全息存储的曝光量范围内对样片曝光引起的图像信噪比损失仅有0.40 dB,说明样片的光学质量高,在全息存储上将具有很好的应用前景. 相似文献
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A general overview of the development of the uses of light-emitting diodes in analytical instrumentation is given. Fundamental aspects of light-emitting diodes, as far as relevant for this usage, are covered in the first part. The measurement of light intensity is also discussed, as this is an essential part of any device based on light-emitting diodes as well. In the second part, applications are discussed, which cover liquid and gas-phase absorbance measurements, flow-through detectors for chromatography and capillary electrophoresis, sensors, as well as some less often reported methods such as photoacoustic spectroscopy. 相似文献