共查询到20条相似文献,搜索用时 15 毫秒
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Xiaofan Ji Kelong Zhu Xuzhou Yan Yingjie Ma Jinying Li Bingjie Hu Yihua Yu Feihe Huang 《Macromolecular rapid communications》2012,33(14):1197-1202
All the previously reported supramolecular polymers based on crown ether‐based molecular recognition have been prepared in anhydrous organic solvents. This is mainly due to the weakness of crown ether‐based molecular recognition in the presence of water. Here we report a linear supramolecular polymer constructed from a heteroditopic monomer in an aqueous medium driven by crown ether‐based molecular recognition through the introduction of electrostatic attraction. In addition, the reversible transition between the linear supramolecular polymer and oligomers is achieved by adding acid and base. This study realizes the breakthrough of the solvent for supramolecular polymerization driven by crown ether‐based molecular recognition from anhydrous organic solvents to aqueous media. It is helpful for achieving supramolecular polymerization driven by crown ether‐based molecular recognition in a completely aqueous medium. 相似文献
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气相色谱中的超分子化学问题:Ⅰ.气相色谱与超分子化学的关系 总被引:1,自引:3,他引:1
超分子化学是有关超分子体系结构和功能的化学,超分子体系是由多个分子作用联系起来的实体,分子识别是形成超分本系的基本特征,本文从分子识别的角度,探讨了气相色谱学中超分子化学问题,并详细地评述了冠醚、液晶、环表固定液的分子识别机理的研究状况,最后,作者们大致展望了色谱研究超分子问题的前景,并且认为在多人工作基础上会产生一门新科学-超分子色谱学。 相似文献
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Jean-Marie Lehn 《Angewandte Chemie (International ed. in English)》1990,29(11):1304-1319
The selective binding of a substrate by a molecular receptor to form a supramolecular species involves molecular recognition which rests on the molecular information stored in the interacting species. The functions of supermolecules cover recognition, as well as catalysis and transport. In combination with polymolecular organization, they open ways towards molecular and supramolecular devices for information processing and signal generation. The development of such devices requires the design of molecular components performing a given function (e.g., photoactive, electroactive, ionoactive, thermoactive, or chemoactive) and suitable for assembly into an organized array. Light-conversion devices and charge-separation centers have been realized with photoactive cryptates formed by receptors containing photosensitive groups. Eleclroactive and ionoactive devices are required for carrying information via electronic and ionic signals. Redox-active polyolefinic chains, like the “caroviologens”, represent molecular wires for electron transfer through membranes. Push-pull polyolefins possess marked nonlinear optical properties. Tubular mesophases, formed by organized stacking of suitable macro-cyclic components, as well as “chundle”-type structures, based on bundles of chains grafted onto a macrocyclic support, represent approaches to ion channels. Lipophilic macrocyclic units form Langmuir-Blodgett films that may display molecular recognition at the air-water interface. Supramolecular chemistry has relied on more or less preorganized molecular receptors for effecting molecular recognition, catalysis, and transport processes. A step beyond preorganization consists in the design of systems undergoing self-organization, that is, systems capable of spontaneously generating a well-defined supramolecular architecture by self-assembling from their components under a given set of conditions. Several approaches to self-assembling systems have been pursued: the formation of helical metal complexes, the double-stranded helicates, which result from the spontaneous organization of two linear polybipyridine ligands into a double helix by binding of specific metal ions; the generation of mesophases and liquid crystalline polymers of supramolecular nature from complementary components, amounting to macroscopic expression of molecular recognition; the molecular-recognition-directed formation of ordered solid-state structures. Endowing photo-, electro-, and ionoactive components with recognition elements opens perspectives towards the design of programmed molecular and supramolecular systems capable of self-assembly into organized and functional supramolecular devices. Such systems may be able to perform highly selective operations of recognition, reaction, transfer, and structure generation for signal and information processing at the molecular and supramolecular levels. 相似文献
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Supramolecular Clippers for Controlling Photophysical Processes through Preorganized Chromophores 下载免费PDF全文
Mohit Kumar Onumashi Afi Ushie Dr. Subi J. George 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(17):5141-5148
A novel supramolecular clipping design for influencing the photophysical properties of functional molecular assemblies, by the preorganization (clipping) of chromophores, is described. Several chromophores end functionalized with molecular recognition units were designed. These molecular recognition units serve as handles to appropriately position these systems upon noncovalent interactions with multivalent guest molecules (supramolecular clippers). Towards this goal, we have synthesized 1,5‐dialkoxynaphthalene (DAN) and naphthalenediimide (NDI) functionalized with dipicolylethylenediamine (DPA) motifs. These molecules could preorganize upon noncovalent clipping with adenosine di‐ or triphosphates, which resulted in preassociated excimers and mixed (cofacial) charge‐transfer (CT) assemblies. Chiral guest binding could also induce supramolecular chirality, not only into the individual chromophoric assembly but also into the heteromeric CT organization, as seen from the strong circular dichroism (CD) signal of the CT transition. The unique ability of this design to influence the intermolecular interactions by changing the binding strength of the clippers furthermore makes it very attractive for controlling the bimolecular photophysical processes. 相似文献
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Barry C. Pemberton Ramya Raghunathan Sabine Volla Jayaraman Sivaguru 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(39):12178-12190
Cucurbiturils are a family of molecular container compounds with superior molecular recognition properties. The use of cucurbiturils for supramolecular catalysis is highlighted in this concept. Both photochemical reactions as well as thermal transformations are reviewed with an eye towards tailoring substrates for supramolecular catalysis mediated by cucurbiturils. 相似文献
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《Current Opinion in Colloid & Interface Science》2003,8(1):55-61
Biological information is transmitted through molecular recognition. This is achieved in aqueous media by ingeniously employing multiple non-covalent interactions as hydrogen bonds, stacking interactions and using appropriate molecular and supramolecular architectures. We review the progress in the search of supramolecular self-assemblies able to reproduce molecular recognition functionalities typical of DNA and RNA. 相似文献
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Azobenzene is one of the most studied light-controlled molecular switches and it has been incorporated in a large variety of supramolecular systems to control their structural and functional properties. Given the peculiar isomeric distribution at the photoexcited state (PSS), azobenzene derivatives have been used as photoactive framework to build metastable supramolecular systems that are out of the thermodynamic equilibrium. This could be achieved exploiting the peculiar E/Z photoisomerization process that can lead to isomeric ratios that are unreachable in thermal equilibrium conditions. The challenge in the field is to find molecular architectures that, under given external circumstances, lead to a given isomeric ratio in a reversible and predictable manner, ensuring an ultimate control of the configurational distribution and system composition. By reviewing early and recent works in the field, this review aims at describing photoswitchable systems that, containing an azobenzene dye, display a controlled configurational equilibrium by means of a molecular recognition event. Specifically, examples include programmed photoactive molecular architectures binding cations, anions and H-bonded neutral guests. In these systems the non-covalent molecular recognition adds onto the thermal and light stimuli, equipping the supramolecular architecture with an additional external trigger to select the desired configuration composition. 相似文献
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芳杂环类多重氢键分子钳人工受体对中性分子的识别性能研究 总被引:3,自引:1,他引:2
根据多点氢键识别原理,设计合成了新的分子钳受体1~6。研究了其对巴比妥 、尿素、二苯甲酮、戊二酰亚胺等中性分子的识别性能。用差紫外光谱法测定了结 合常数和自由能变化(ΔG)。结果表明,所有分子钳受体与所考察的客体分子均 形成1:1型超分子配合物,识别作用的推动力主要为多重氢键的协同作用。讨论了 主客体间尺寸/形状、几何互补等因素对形成超分子配合物的影响。并利用~1H NMR、计算机模拟作辅助手段对实验结果和现象进行了解释。 相似文献
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Melegari M Suman M Pirondini L Moiani D Massera C Ugozzoli F Kalenius E Vainiotalo P Mulatier JC Dutasta JP Dalcanale E 《Chemistry (Weinheim an der Bergstrasse, Germany)》2008,14(19):5772-5779
Phosphonate cavitands are an emerging class of synthetic receptors for supramolecular sensing. The molecular recognition properties of the third-generation tetraphosphonate cavitands toward alcohols and water at the gas-solid interface have been evaluated by means of three complementary techniques and compared to those of the parent mono- and diphosphonate cavitands. The combined use of ESI-MS and X-ray crystallography defined precisely the host-guest association at the interface in terms of type, number, strength, and geometry of interactions. Quartz crystal microbalance (QCM) measurements then validated the predictive value of such information for sensing applications. The importance of energetically equivalent multiple interactions on sensor selectivity and sensitivity has been demonstrated by comparing the molecular recognition properties of tetraphosphonate cavitands with those of their mono- and diphosphonate counterparts. 相似文献
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Hao Zhao Dr. Sameer Hussain Xiaoyan Liu Shengliang Li Dr. Fengting Lv Dr. Libing Liu Prof. Shu Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(42):9834-9839
Introduction of chirality into a supramolecular self-assembly system plays an indispensable role in attaining specific molecular recognition ability. Herein, a chiral anticancer drug 5′-deoxy-5-fluorouridine (5′DFU) was explored for inducing the self-assembly of a cationic perylene diimide derivative containing boronic acid groups (PDI-PBA) into a highly ordered right-handed helical structure. As a result, PDI-PBA exhibited a molecular recognition ability towards 5′DFU among other cis-diols and anticancer drugs. With the help of a dynamic covalent bond and favorable hydrogen-bonding interactions, chirality transfer from chiral 5′DFU to achiral PDI-PBA breaks down the strong π–π stacking of PDI-PBA and makes it reorganize into highly ordered helical supramolecular structures. This work provides an insight into chiral anticancer drug tuning interactions of π-chromophores and the inducement of hierarchical self-assembly to achieve specific molecular recognition. 相似文献
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氨基甲酸酯型脱氧胆酸分子钳对中性分子的识别性能研究 总被引:3,自引:0,他引:3
利用差紫外光谱法考察了新型分子钳1~6对苯胺、对硝基苯胺、对甲氧基苯胺等中性分子的识别性能, 测定了25 ℃下, 在CHCl3中主客体间的结合常数(Ka)和自由能变化(ΔG0). 结果表明, 所有分子钳主体对所考察的客体分子显示良好的识别作用, 主客体间形成1∶1型主客体络合物. 识别作用的主要推动力为多重氢键和π-π重叠等的作用. 讨论了主客体间形状、大小匹配和几何互补及识别模式等因素对识别能力的影响, 并利用核磁共振氢谱与计算机模拟作为辅助手段对实验结果进行了解释. 相似文献
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Complete control of the selective and reversible interaction of molecules from the gas or liquid phase at complementary recognition
sites is of increasing interest for both basic science and practical applications. This recognition may occur at the surface
or in the bulk of optimized chemically sensitive coatings. It is either monitored discontinuously by chromatography or continuously
by a suitable sensor. The latter contains the optimized coating and converts the chemical information about concentrations
of certain molecules by means of a certain transducer into an electronic signal. Generally speaking, these transducers form
the essential part of ‘chemical sensors’; they monitor the molecular interactions at the chemically sensitive layer by changes
in resistivity, impedance, mass, capacitance, work function, heat, electrochemical potential, optical thickness, or optical
absorption in a certain spectral range. Three selected case studies of such molecular recognition devices which utilize supramolecular,
polymeric, and biomimetic coatings are presented. Examples are given for both gas and liquid sensing devices. For simplification,
because of its general applicability and its easy absolute calibration, particular emphasis is put on signal transduction
via quartz crystal oscillators. The measurement principle is based on frequency changes which are directly correlated with
mass changes and thus provide a particularly suitable signal transduction. The examples presented here concern systematic
variations in the design of supramolecular cages, of selective interaction sites in polymeric matrices, and of covalently
attached biomimetic recognition sites to monitor antibodies or enzyme interactions.
Received: 11 August 1997 / Revised: 3 March 1998 / Accepted: 3 March 1998 相似文献
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Molecular recognition: Supramolecular, polymeric and biomimetic coatings for chemical sensors and chromatographic columns 总被引:2,自引:0,他引:2
Complete control of the selective and reversible interaction of molecules from the gas or liquid phase at complementary recognition
sites is of increasing interest for both basic science and practical applications. This recognition may occur at the surface
or in the bulk of optimized chemically sensitive coatings. It is either monitored discontinuously by chromatography or continuously
by a suitable sensor. The latter contains the optimized coating and converts the chemical information about concentrations
of certain molecules by means of a certain transducer into an electronic signal. Generally speaking, these transducers form
the essential part of ‘chemical sensors’; they monitor the molecular interactions at the chemically sensitive layer by changes
in resistivity, impedance, mass, capacitance, work function, heat, electrochemical potential, optical thickness, or optical
absorption in a certain spectral range. Three selected case studies of such molecular recognition devices which utilize supramolecular,
polymeric, and biomimetic coatings are presented. Examples are given for both gas and liquid sensing devices. For simplification,
because of its general applicability and its easy absolute calibration, particular emphasis is put on signal transduction
via quartz crystal oscillators. The measurement principle is based on frequency changes which are directly correlated with
mass changes and thus provide a particularly suitable signal transduction. The examples presented here concern systematic
variations in the design of supramolecular cages, of selective interaction sites in polymeric matrices, and of covalently
attached biomimetic recognition sites to monitor antibodies or enzyme interactions.
Received: 11 August 1997 / Revised: 3 March 1998 / Accepted: 3 March 1998 相似文献
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氢键识别超分子聚合物的新进展* 总被引:1,自引:0,他引:1
近年来,由于氢键作用对聚合物的热力学性质、微观自组装、结晶及液晶行为的重要影响,氢键识别在超分子聚合物的分子设计与结构控制方面的应用受到广泛关注。本文系统介绍了氢键识别体系的类型与性质,以及分子结构、分子内氢键对氢键识别强度的影响,讨论了羧酸与吡啶间氢键识别体系、与核苷相关的氢键识别体系以及四重氢键识别体系在超分子聚合物中的最新应用,主要介绍了氢键识别超分子聚合物的合成、结构、性质及功能。 相似文献
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An Elaborate Supramolecular Assembly for a Smart Nanodevice for Ratiometric Molecular Recognition and Logic Gates 下载免费PDF全文
Yu‐Jie Xie Wen‐Yu Wu Hao Chen Xiang Li Prof. Hao‐Li Zhang Liang‐Liang Liu Xing‐Xin Shao Chang‐Fu Shan Prof. Wei‐Sheng Liu Prof. Yu Tang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(24):8339-8345
Ingenious approaches to supramolecular assembly for fabricating smart nanodevices is one of the more significant topics in nanomaterials research. Herein, by using surface quaternized cationic carbon dots (CDots) as the assembly and fluorescence platform, anionic sulfonatocalix[4]arene with modifiable lower and upper rims as a connector, as well as in situ coordination of Tb3+ ions, we propose an elaborate supramolecular assembly strategy for the facile fabrication of a multifunctional nanodevice. The dynamic equilibrium characteristics of the supramolecular interaction can eventually endow this nanodevice with functions of fluorescent ratiometric molecular recognition and as a nano‐logic gate with two output channels. 相似文献
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Dr. Taisuke Matsuno Dr. Sota Sato Dr. Atsutoshi Yokoyama Sho Kamata Prof. Dr. Hiroyuki Isobe 《Angewandte Chemie (International ed. in English)》2016,55(49):15339-15343
Non‐directional van der Waals forces in biological and synthetic supramolecular systems play important roles in molecular assembly, particularly in determining the distances of the interacting species. The van der Waals forces are normally used in combination with other directional forces and are considered to play a secondary role in achieving specificity and fidelity in molecular recognition. Using an ideal supramolecular system consisting solely of hydrogen and carbon atoms, we found that the van der Waals interactions enable the high‐fidelity sorting of two homomeric receptors during ligand‐induced assembly. The self‐sorting occurred in a narcissistic manner by repulsion of a competing diastereoisomeric receptor from the assembly. The structure–sorting relationship study with enantiomers further revealed the dominant role of the van der Waals forces in shape recognition for high‐fidelity self‐sorting. 相似文献