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含氮鎓阴离子受体是目前阴离子识别领域研究的热点之一,此类受体具有主体结构修饰的灵活性和多样性,能更好的发挥氢键、疏水作用、静电作用、π-π作用、阴离子-π作用的协同效应等优点。本文详细评述了咪唑鎓和吡啶鎓两类含氮鎓受体的设计、结构及其阴离子识别作用的研究进展。 相似文献
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硫脲类阴离子受体的设计合成与阴离子识别 总被引:2,自引:0,他引:2
硫脲类化合物具有生物活性,是优良的氢键供体,与阴离子特别是含氧阴离子形成氢键配合物。本文设计合成了系列二苯基硫脲衍生物,通过取代基效应调控硫脲衍生物分子内电转移过程,阴离子与硫脲基团结合后,增强了分子内供体的给电子能力,进一步促进电荷转移过程,据此识别不同的阴离子。由于主体分子与阴离子间形成氢键的能力及阴离子碱性的差异,可达到选择性结合的目的。 相似文献
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作为优良的氢键给予体,脲基(-NH-CO-NH-)是构筑阴离子识别受体的理想结构单元.而电化学方法因其方便快捷、灵敏度高等优点,近年来被广泛应用于阴离子的识别检测.本文对脲类受体的电化学阴离子识别进行了讨论,主要包括:(i) 归纳整理了电化学阴离子识别的机理,包括识别位点与阴离子结合之后对氧化还原中心的5种扰动机理和溶液中电化学测试受体和阴离子相互作用时常见现象的分析及对应结合常数的计算; (ii) 电活性脲类阴离子受体的研究进展,包括受体分子的设计、识别和机理; (iii) 探讨了该领域的后续发展方向. 相似文献
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近来,科学家设计和合成了系列分子水平的陀螺。类似于儿童的玩具陀螺仪,这种分子陀螺由一个转子、一个定子框架和连接定子和转子的轴组成。定子框架通过自身的刚性结构为中心转子的转动提供足够的内在自由度,得以对内部的转子实施保护。并使得分子陀螺成为一个理想的分子转子。当转子上有偶极距时,则可能在外来电、磁、光的刺激下进行定向转动,成为分子马达。化学家们通过X射线晶体衍射技术、动态核磁技术、理论计算化学、热力学分析等方法表征了分子陀螺的各种特征,并积极探索其潜在的应用价值。本文着重介绍分子陀螺,以及超分子陀螺仪的发展历史以及研究进展。 相似文献
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Taken to the molecular level, the concept of “tweezers” opens a rich and fascinating field at the convergence of molecular recognition, biomimetic chemistry and nanomachines. Composed of a spacer bridging two interaction sites, the behaviour of molecular tweezers is strongly influenced by the flexibility of their spacer. Operating through an “induced‐fit” recognition mechanism, flexible molecular tweezers select the conformation(s) most appropriate for substrate binding. Their adaptability allows them to be used in a variety of binding modes and they have found applications in chirality signalling. Rigid spacers, on the contrary, display a limited number of binding states, which lead to selective and strong substrate binding following a “lock and key” model. Exquisite selectivity may be expressed with substrates as varied as C60, nanotubes and natural cofactors, and applications to molecular electronics and enzyme inhibition are emerging. At the crossroad between flexible and rigid spacers, stimulus‐responsive molecular tweezers controlled by ionic, redox or light triggers belong to the realm of molecular machines, and, applied to molecular tweezing, open doors to the selective binding, transport and release of their cargo. Applications to controlled drug delivery are already appearing. The past 30 years have seen the birth of molecular tweezers; the next many years to come will surely see them blooming in exciting applications. 相似文献
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化学及生物体系中的分别识别* 总被引:3,自引:0,他引:3
分子识别的目标是研究分子间专一性地相互作用, 这在化学及生命过程中起着非常重要的作用。本文综述了分子识别的机制及其在化学、生命科学、材料、信息等有关学科中的应用。 相似文献
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Any kind of device or machine requires a substrate, energy, and information signals. If we wish to operate at the nanometer scale, we must use molecules as substrates. Energy- and signal-processing at a molecular level relies on cause/effect relationships between the input supplied and the kind of process obtained. We have classified energy- and signal-processing at the molecular level according to the nature of the input (electronic, photonic, or chemical) and the nature of the obtained effect (electronic, photonic, or chemical process that follows). By coupling the three kinds of inputs with the three types of resulting processes, nine types of molecular-based processes (electronic, photonic, chemionic, electrophotonic, electrochemionic, photoelectronic, photochemionic, chemiophotonic, and chemioelectronic) can be identified. In this concept article, looking at molecular transformations in an unconventional way, we have tried to give a flavor of some of the new features that project the old science of chemistry towards novel achievements. 相似文献
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search for the lowest energy conformation of complex {β-cyclodextrin
(β-CD)+chlorambucil} were carried out by molecular mechanics method.
Theoretical calculations of molecular interactions of complex were carried
out using the molecular orbital method. The correlation between energy changes
and molecular structures are discussed. The large interaction energies calculated
by the molecular orbital method bears out the inclusion phenomenon. 相似文献