共查询到20条相似文献,搜索用时 62 毫秒
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法国斯特拉斯堡大学的让-皮埃尔·索维奇(Jean-Pierre Sauvage)和美国西北大学的弗雷泽·斯托达特(J.Fraser Stoddart)利用机械键设计了锁链分子机器--索烃和轮烷,荷兰格罗宁根大学的伯纳德·费林加(Bernard L.Feringa)基于不饱和键合成分子马达实现了分子机器的单向旋转,3位科学家因“设计、合成分子机器”而被授予2016年诺贝尔化学奖。 相似文献
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由于具有三维空腔结构及良好的应用前景, 穴醚逐渐成为超分子研究领域的热点之一. 近年来, 我们课题组设计合成了一系列基于双间苯-32-冠-10穴醚主体分子, 并利用这些穴醚分子构筑了不同的超分子组装体. 首先, 将双硫代四硫富瓦烯(STTFS)引入到穴醚的第三个臂上, 成功构筑了具有氧化还原响应性的穴醚主体分子. 该穴醚与客体间的解离-穿环过程可以利用STTFS的氧化态来进行控制; 其次, 设计合成了两种含有P=O官能团桥连的穴醚, 在固态结构中得到了近似线型和Z字型的不同超分子聚[2]准轮烷; 最后, 合成了具有两种不同性质空腔的柱[5]芳烃稠合穴醚主体分子, 该穴醚通过正交作用同时络合两个不同的客体分子. 基于两种不同主客体作用力, 我们构筑了一种新型的超分子聚合物. 以上研究为分子器件和超分子材料的进一步研究奠定了良好的基础. 相似文献
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可利用酸碱调控的分子器件—富电子二苯醚客体和缺电子联吡啶大环组成的准轮 总被引:5,自引:2,他引:5
利用π-π堆积作用,富电子4,4‘-二氨基二苯醚(A)和4,4‘-二羟基二苯醚(B)分别与缺电子联吡啶大环(CPQT)自组装成准轮烷A-CPQT和B-CPQT;利用酸碱调控准轮烷A-CPQT与“开”与“关”,此过程可利用体系的核磁共振氢谱的化学永化进行跟踪。 相似文献
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Dr. Maxime Gauthier Dr. Karine Fournel-Marotte Dr. Caroline Clavel Dr. Philip Waelès Dr. Philippe Laurent Dr. Frédéric Coutrot 《Angewandte Chemie (International ed. in English)》2023,62(44):e202310643
Here is reported the synthesis and characterization of an interlocked figure-of-eight rotaxane molecular shuttle from a dibenzo-24-crown-8 (DB24C8) derivative. This latter bears two molecular chains, whose extremities are able to react together by click chemistry. One of the two substituting chain holds an ammonium function aimed at driving the self-entanglement through the complexation of the DB24C8 moiety. In the targeted figure-of-eight rotaxane, shuttling of the DB24C8 along the threaded axle from the best ammonium station to the weaker binding site triazolium was performed through deprotonation or deprotonation-then-carbamoylation of the ammonium. This way, two discrete co-conformational states were obtained, in which the folding and size of the two loops could be changed. 相似文献
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30-冠-10对生物极性客体的分子识别和分子开关 总被引:1,自引:0,他引:1
用AM1,MNDO和PM3方法对30-冠-10与苯衍生物及其生物活性物质脱氧核糖、核糖和呋喃果糖的超分子配合物进行理论研究,得到配合物的稳定化能,结果表明,冠醚对极性客体具有识别作用,尤其对脱氧核糖的识别效果较好。用INDO/SCI方法计算超分子配合物的电子吸收光谱,计算结果表明,配合物的光谱吸收峰与主体相比发生蓝移。探讨了冠醚和间二苯甲酸配合物的分子开关的形成机理。 相似文献
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采用金属离子为模板合成了-类由无金属或金属卟啉修饰的冠醚大分子环,并通过1HNMR、MS、紫外、荧光等方法对其进行了结构表征和性能测试.采用具有4,4,-联吡啶的客体分子与冠醚环进行组装,以荧光滴定法测定了主客体分子问的结合常数.结果表明,这种冠醚环不仅具有卟啉优异的光电性质而且能与客体分子形成了1:1的类轮烷体系. 相似文献
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Pb8FeIIFeF24 is triclinic: a = 20.118(3) Å, b = 5.597(1) Å, c = 9.440(2) Å, α = 89.75(2)°, β = 105.79(2)°, α = 89.38(2)°, Z = 2. The structure is solved in the unconventional space group C1 , from X-ray single crystal data using 1 641 independent reflections (R = 0.048, Rw = 0.051). It is built up from the stacking of two subnetworks along the a axis: fluorite-like [Pb8F10]n6n+ layers and infinite dimetallic [FeIIFeF14]n6n? double-chains of corner-sharing octahedra running along the b axis. 相似文献
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We investigated the threading of bis(benzimidazolium) methane moieties with DB24C8 at 35 °C (room temperature) and found a high degree of association. The presence of threaded complexes was determined by 1H NMR and also supported by high resolution mass spectrometry and B3LYP/6-31G**++calculations. A 2D NMR study was done to elucidate the host-guest geometry and the molecular interactions present. The variable temperature NMR experiment was done over a temperature range of 243-323 K. The threading was stable and visible even at 323 K. Acid-base equilibrium established the reversibility of the process. DFT optimized structures establish that two H-bonded links are present between O1?O4′ and O3?O2′ across the dibenzo axis of the crown. 相似文献
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李宗良 《化学物理学报(中文版)》2011,24(2):194-198
Based on the first-principles computational method and the elastic scattering Green's func-tion theory, we have investigated the electronic transport properties of different oligothio-phene molecular junctions theoretically. The numerical results show that the difference of geometric symmetries of the oligothiophene molecules leads to the difference of the contact configurations between the molecule and the electrodes, which results in the difference of the coupling parameters between the molecules and electrodes as well as the delocalization properties of the molecular orbitals. Hence, the series of oligothiophene molecular junctions display unusual conductive properties on the length dependence. 相似文献
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TRPM8通道的温度感知等生理功能依赖于正常的门控, 但现有晶体结构中S6跨膜螺旋C末端形成的门控结构存在氨基酸缺失, 所以其门控特性未能揭晓. 本文基于已有的晶体结构和AlphaFold算法构建了 11个完整不同构象的TRPM8通道, 发现其S6跨膜螺旋C末端构成的门控存在回环和螺旋2种构象. 在回环构象中, 多个氨基酸参与形成阻碍离子通透的孔道区; 而在螺旋构象中, 仅有关键氨基酸V956发挥门控作用. 由于回环构象的柔性大于螺旋构象, 导致回环构象参与阻碍离子通透的关键氨基酸构象和数量变化多样. 二级结构预测与模建结果表明, S6跨膜螺旋C末端存在回环构象向螺旋构象的转变, 此过程中柔性的回环构象结构域向胞外侧上移, 关键氨基酸向孔道衬外扭转, 增强了与相邻跨膜螺旋S5的相互作用以及S5与TRP螺旋之间的相互作用, 进而形成刚性、 稳定且有序的螺旋构象. 这增加了TRPM8通道各结构域间的协同性, 使能量信息更高效地传递到门控结构域, 为TRPM8通道开启蓄势. 相似文献
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Light‐ and Redox‐Gated Molecular Brakes Consisting of a Pentiptycene Rotor and an Indole Pad 下载免费PDF全文
Two photochemically and electrochemically active alkenes 3Me and 3An containing pentiptycene and indole groups have been synthesized and investigated as light and/or redox‐gated molecular brakes. The pentiptycene group functions as the four‐bladed rotor, the indole group as the brake pad, and the vinylene group as the switch module. The E configuration corresponds to the brake‐off state, in which the rotation of the rotor is free with a rotation rate of 108‐109 at ambient temperature according to DFT calculations. The Z configuration corresponds to the brake‐on state, in which the rotation rate is decreased to 101‐102, depending on the N‐substituent of indole, according to line‐shape analysis of variable temperature 13C NMR spectra. The overall braking effect reaches a factor of 106‐108. While the combined photochemical E → Z and electrochemical Z → E switching has a higher capacity than the two‐way photochemical switching in the case of 3Me , the switching capacity are comparable for the two methods in 3An . The results also show that photochemical E‐Z isomerization is much more reliable than the electrochemical counterpart, as the stability of the redox intermediates plays a critical role in determining the robustness of the molecular brakes via electrochemical switching. 相似文献
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Synthesis and Crystal Structure of [Na(DB24C8)]2(WMo5O19) 总被引:4,自引:1,他引:4
SynthesisandCrystalStructureof[Na(DB24C8)]_2(WMo_5O_(19))¥LuXiao-Ming;LiuGuo-Xiang;TuShu-Jie;Liushun-Cheng(DepartmentofChemist?.. 相似文献