Cage Compound

笼式化合物
  • 文章类型: Journal Article
    自修复能力对于提高材料的寿命和可靠性至关重要。在这项研究中,使用封装氟离子(F-)的可裂解笼状化合物实现聚硅氧烷材料愈合的时空控制,这触发了硅氧烷(Si-O-Si)网络的动态重排。通过使聚二甲基硅氧烷(PDMS)与F-封装笼型锗烷(Ge-O-Ge)化合物交联来制备自修复硅氧烷基弹性体。这种材料可以在潮湿条件下反复自愈。通过笼形框架的水解裂解而释放的F通过促进硅氧烷网络的局部重排而有助于切割块的重新接合。使用包封催化剂的分子笼进行动态键重排提供了基于集成的外在和内在机理设计自修复聚硅氧烷材料的新概念。
    Self-healing ability is crucial to increasing the lifetime and reliability of materials. In this study, spatiotemporal control of the healing of a polysiloxane material is achieved using a cleavable cage compound encapsulating a fluoride ion (F- ), which triggeres the dynamic rearrangement of the siloxane (Si-O-Si) networks. A self-healing siloxane-based elastomer is prepared by cross-linking polydimethylsiloxane (PDMS) with a F- -encapsulating cage-type germoxane (Ge-O-Ge) compound. This material can self-heal repeatedly under humid conditions. The F- released by hydrolytic cleavage of the cage framework contributes to rejoining of the cut pieces by promoting the local rearrangement of the siloxane networks. The use of a molecular cage encapsulating a catalyst for dynamic bond rearrangement provides a new concept for designing self-healing polysiloxane materials based on integrated extrinsic and intrinsic mechanisms.
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  • 文章类型: Journal Article
    多面体分子因其引人注目的结构和独特的化学而吸引人。这样的全氟化,通常会产生很大的应变,是一个重大挑战。它极大地改变了电子分布,结构和属性。值得注意的是,小型高对称性全氟多面体的特征是位于中央,星形低能未占据的分子轨道,可以在多面体框架内承载一个额外的电子,从而产生自由基阴离子,不失去对称性。这种预测的电子托管能力肯定是为全氟卡布确定的,第一个被分离纯的全氟化柏拉图式多面体。承载原子,这种“笼子”结构中的分子或离子是,然而,除了直率,当不是虚幻的时候,提供不容易获得超分子结构。虽然金刚烷和古巴在材料科学中促进了许多应用,医学和生物学,其全氟对应物的具体用途仍有待确定。高氟化碳同素异形体的某些方面,如富勒烯或石墨,简要提及上下文。
    Polyhedral molecules are appealing for their eye-catching architecture and distinctive chemistry. Perfluorination of such, often greatly strained, compounds is a momentous challenge. It drastically changes the electron distribution, structure and properties. Notably, small high-symmetry perfluoropolyhedranes feature a centrally located, star-shaped low-energy unoccupied molecular orbital that can host an extra electron within the polyhedral frame, thus producing a radical anion, without loss of symmetry. This predicted electron-hosting capacity was definitively established for perfluorocubane, the first perfluorinated Platonic polyhedrane to be isolated pure. Hosting atoms, molecules, or ions in such \"cage\" structures is, however, all but forthright, if not illusionary, offering no easy access to supramolecular constructs. While adamantane and cubane have fostered numerous applications in materials science, medicine, and biology, specific uses for their perfluorinated counterparts remain to be established. Some aspects of highly fluorinated carbon allotropes, such as fullerenes and graphite, are briefly mentioned for context.
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  • 文章类型: Journal Article
    机械互锁结构是令人着迷的合成目标,通过连接实现的拓扑复杂性为构建具有令人兴奋特性的新分子提供了许多可能性。在连接有机笼分子的结构空间中,到目前为止,只有很少的例子被实现,并且对解决方案中的级联过程的控制仍然勉强实现。在这里,我们描述了巨大的手性[812]水杨酸立方体的四层互锁的catenane的形成。可以通过选择反应中使用的溶剂来控制形成。互锁结构通过单晶X射线衍射明确表征,并且弱氢键被确定为链接的中心驱动力。此外,使用部分氘代笼子进行了加扰实验,揭示了catenane的形成是通过预制单笼的机械互锁而发生的。
    Mechanically interlocked structures are fascinating synthetic targets and the topological complexity achieved through catenation offers numerous possibilities for the construction of new molecules with exciting properties. In the structural space of catenated organic cage molecules, only few examples have been realized so far, and control over the catenation process in solution is still barely achieved. Herein, we describe the formation of a quadruply interlocked catenane of giant chiral [8+12] salicylimine cubes. The formation could be controlled by the choice of solvent used in the reaction. The interlocked structure was unambiguously characterized by single crystal X-ray diffraction and weak hydrogen bonding was identified as a central driving force for the catenation. Furthermore, scrambling experiments using partially deuterated cages were performed, revealing that the catenane formation occurs through mechanical interlocking of preformed single cages.
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  • 文章类型: Journal Article
    具有多样结构和显著生物活性的天然产物是药物先导化合物的重要来源,并在创新药物的研发中发挥重要作用。笼状化合物结构多样,在自然界中分布广泛,特别是从藤黄属中分离出的笼养的黄原酮,从白芍中分离出的芍药苷及其衍生物,河豚毒素(TTX)及其衍生物,等等。近年来,笼状化合物的开发和利用一直是化学研究的热点,生物学等领域由于其特殊的结构和显著的生物活性。在这次审查中,我们主要总结了自1956年以来从天然药物中发现和分离出的各种结构的笼状化合物,总结了其广泛的生物活性,并介绍了一些化合物的生物合成进展,从而为发现更多新化合物提供参考,以及创新药物的开发和应用。
    Natural products with diverse structures and significant biological activities are essential sources of drug lead compounds, and play an important role in the research and development of innovative drugs. Cage-like compounds have various structures and are widely distributed in nature, especially caged xanthones isolated from Garcinia genus, paeoniflorin and its derivatives isolated from Paeonia lactiflora Pall, tetrodotoxin (TTX) and its derivatives, and so on. In recent years, the development and utilization of cage-like compounds have been a research hotspot in chemistry, biology and other fields due to their special structures and remarkable biological activities. In this review, we mainly summarized the cage-like compounds with various structures found and isolated from natural drugs since 1956, summarized its broad biological activities, and introduced the progress in the biosynthesis of some compounds, so as to provide a reference for the discovery of more novel compounds, and the development and application of innovative drugs.
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  • 文章类型: Journal Article
    将反应性官能团结合到金属有机笼(MOCs)的外部为将其定义明确的支架连接到功能多孔固体中开辟了新的机会。胺部分提供了丰富的共价化学目录;然而,它们还倾向于不期望地协调并干扰MOC的形成,特别是在基于Cu2桨轮的MOCs的情况下。我们证明,调整苯胺官能化配体的碱度可以使可溶性,胺官能化Cu4L4灯笼(1)。重要的是,我们显示了对配体外部胺的配位倾向的控制,这使我们能够分离出晶体,完全由MOC单元组成的二维金属有机框架(2)。此外,我们表明,1的外部胺的亲核性可以在溶液中通过亚胺缩合产生交联的笼状聚合物(3)。
    The incorporation of reactive functional groups onto the exterior of metal-organic cages (MOCs) opens up new opportunities to link their well-defined scaffolds into functional porous solids. Amine moieties offer access to a rich catalogue of covalent chemistry; however, they also tend to coordinate undesirably and interfere with MOC formation, particular in the case of Cu2 paddlewheel-based MOCs. We demonstrate that tuning the basicity of an aniline-functionalized ligand enables the self-assembly of a soluble, amine-functionalized Cu4L4 lantern cage (1). Importantly, we show control over the coordinative propensity of the exterior amine of the ligand, which enables us to isolate a crystalline, two-dimensional metal-organic framework composed entirely of MOC units (2). Furthermore, we show that the nucleophilicity of the exterior amine of 1 can be accessed in solution to generate a cross-linked cage polymer (3) via imine condensation.
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  • 文章类型: Journal Article
    合成了两个类似的M4L4型四面体笼(较小:MOC-19;较大:MOC-22),并通过NMR光谱研究了它们与抗癌药物5-氟嘧啶(5-FU)的相互作用,高分辨率电喷雾电离质谱(HR-ESI-MS),和分子模拟。笼子的大小和窗口对于主客绑定很重要,因此,发现具有更合适尺寸的腔窗的较小的MOC-19与5-FU具有更强的氢键相互作用。MOC-19的多孔纳米颗粒在具有液体磷酸盐缓冲盐水溶液的模拟人体中表现出5-FU的受控释放的出色行为。
    Two analogous M4 L4 -type tetrahedral cages (smaller: MOC-19; larger: MOC-22) were synthesized and investigated for their interactions with the anticancer drug 5-fluoracil (5-FU) by NMR spectroscopy, high-resolution electrospray-ionization mass spectrometry (HR-ESI-MS), and molecular simulation. The cage\'s size and window are of importance for the host-guest binding, and consequently the smaller MOC-19 with a more suitable size of cavity window was found to have much stronger hydrogen-bond interactions with 5-FU. The porous nanoparticles of MOC-19 exhibited outstanding behavior for the controlled release of 5-FU in a simulated human body with liquid phosphate-buffered saline solution.
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  • 文章类型: Journal Article
    免疫细胞信号的空间和时间方面是定义免疫应答大小的关键参数。先天免疫细胞上的Toll样受体(TLR)在病原体的早期检测和免疫应答的启动中很重要。控制TLR的空间和时间信号传导将能够进一步研究免疫协同作用并有助于开发新疫苗。这里,我们展示了一种基于光的TLR4信号的空间控制方法。TLR4激动剂,嘧啶并[5,4-b]吲哚,在受体结合的关键位置用笼保护。这提供了一种光可控激动剂,在笼子里没有活性,在UV光控脱保护后,细胞中的NF-κB活性受到影响。我们通过用笼状TLR4激动剂处理所有细胞并限制光暴露和随后对感兴趣区域的激活,证明了细胞群内NF-κB激活的空间控制。
    The spatial and temporal aspects of immune cell signaling are key parameters in defining the magnitude of an immune response. Toll-like receptors (TLRs) on innate immune cells are important in the early detection of pathogens and initiation of an immune response. Controlling the spatial and temporal signaling of TLRs would enable further study of immune synergies and assist in the development of new vaccines. Here, we show a light-based method for the spatial control of TLR4 signaling. A TLR4 agonist, pyrimido[5,4-b]indole, was protected with a cage at a position critical for receptor binding. This afforded a photocontrollable agonist that was inactive while caged, yet effected NF-κB activity in cells following UV photocontrolled deprotection. We demonstrated spatial control of NF-κB activation within a population of cells by treating all cells with the caged TLR4 agonist and constraining light exposure and consequent activation to a region of interest.
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