chirality

手性
  • 文章类型: Journal Article
    手性农药约占农药总量的40%。在使用杀虫剂的过程中,它将不可避免地流入地表水,甚至通过地表径流和其他方式渗透到地下水中,因此,影响水环境。尽管手性农药的对映体具有相同的物理和化学性质,他们的分布,比率,新陈代谢,毒性,等。在生物体中往往是不同的,有时甚至表现出完全相反的生物活动。在这篇文章中,不同类型手性农药如有机氯的选择性命运,有机磷,三唑,拟除虫菊酯和天然水体和沉积物中的其他手性农药,对水生生物的急性毒性,从慢性毒性等方面进行综述,进一步反映手性农药对映体对水环境中非靶标生物的风险。在这次审查中,我们希望通过手性农药对映体的毒性研究,进一步探讨其对人类社会的危害,从而为生化农药的开发和生产提供数据支持和理论依据。
    Chiral pesticides account for about 40% of the total pesticides. In the process of using pesticides, it will inevitably flow into the surface water and even penetrate into the groundwater through surface runoff and other means, as a consequence, it affects the water environment. Although the enantiomers of chiral pesticides have the same physical and chemical properties, their distribution, ratio, metabolism, toxicity, etc. in the organism are often different, and sometimes even show completely opposite biological activities. In this article, the selective fate of different types of chiral pesticides such as organochlorine, organophosphorus, triazole, pyrethroid and other chiral pesticides in natural water bodies and sediments, acute toxicity to aquatic organisms, chronic toxicity and other aspects are summarized to further reflect the risks between the enantiomers of chiral pesticides to non-target organisms in the water environment. In this review, we hope to further explore its harm to human society through the study of the toxicity of chiral pesticide enantiomers, so as to provide data support and theoretical basis for the development and production of biochemical pesticides.
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  • 文章类型: Journal Article
    本文讨论了手性金属配合物,并从组装结构介绍了对映体。由于金属离子作为手性中心的不同配位数和活性,丰富的手性选择性结构,催化作用,和偏振光响应是手性金属配合物的显着优势。线性多齿配体的合理设计和制备是提高手性配合物稳定性的良好选择,如多键合结构作为自限制系统的高稳定性。讨论了手性金属配合物的生物意义和潜在应用,如酶中金属中心的催化和手性选择性的协同作用。酶可以被重塑,用高活性的稀土或贵金属离子代替原来的中心金属离子,形成人工金属酶或去除金属中心周围的“多余”部分,以提高底物的可及性。介绍了手性视蛋白的偏振光响应机制及其在动物迁移中的作用。金属有机骨架(MOF)是由金属节点或簇和有机连接基构建的晶体和多孔材料,为制备人工对映体提供了可能性。准备工作,应用程序,并介绍了MOF局部形态的表征方法。我们希望这篇评论能激发职业生涯各个层面的研究人员在自己的研究中考虑标题主题的应用和潜在价值。
    This review discusses chiral-at-metal complexes and introduces enantiomorphs from assembly structure. Owing to the diverse coordination number and activity of metal ions as chiral centers, abundant structures for chiral selectivity, catalysis, and polarized light-response are the notable advantages of the chiral-at-metal complexes. The rational design and preparation of linear multi-dentate ligands is a good choice to improve the stability of chiral complexes, such as multi-bonding structure for high stability as a self-limiting system. The bio-significance and potential application of chiral-at-metal complexes are discussed, such as the synergistic effect of catalysis and chiral selectivity of the metal center in enzymes. Enzyme could be remolded to replace the original central metal ions with highly active rare earth or precious metal ions to form artificial metalloenzyme or to remove the \"redundant\" part around the metal center to improve the accessibility of substrate. The polarized light-response mechanism of chiral opsin is introduced in relation to its role in animal migration. Metal-organic frameworks (MOFs) are crystalline and porous materials built from metal nodes or clusters and organic linkers and provide the possibility to prepare artificial enantiomorphs. The preparations, applications, and characterization methods of MOF enatiomorphs are therefore introduced. We hope this review inspires researchers at all levels of their career to consider the title topic in their own research in terms of its application and potential value.
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  • 文章类型: Journal Article
    由于缺乏氨基糖与老化,人们将患有各种被世界卫生组织称为“不死癌症”的流行性骨病。骨组织工程中尚未完全解决的关键问题是修复严重的大规模骨和软骨缺损。细胞外基质的手性对骨细胞的生理活动和骨组织的发生起着决定性的作用,但手性调节细胞粘附和生长的机制仍处于早期探索阶段。本文综述了基于“软”和“硬”支架的手性仿生支架在骨缺损修复中的应用进展。目的总结不同手性结构(l形和d形)在诱导仿生支架修复骨缺损过程中的作用。此外,还介绍了制备手性诱导仿生支架的许多技术和方法以及值得特别考虑的问题。期望这项工作可以为设计新型手性诱导仿生支架提供鼓舞人心的思路,并促进手性在骨组织工程中的发展。
    Due to lack of amino sugar with aging, people will suffer from various epidemic bone diseases called \"undead cancer\" by the World Health Organization. The key problem in bone tissue engineering that is not completely resolved is the repair of critical large-scale bone and cartilage defects. The chirality of the extracellular matrix plays a decisive role in the physiological activity of bone cells and the occurrence of bone tissue, but the mechanism of chirality in regulating cell adhesion and growth is still in the early stage of exploration. The application progress of chirality-induced bionic scaffolds is reviewed here in bone defects repair based on \"soft\" and \"hard\" scaffolds. The aim is to summarize the effects of different chiral structures (l-shaped and d-shaped) in the process of inducing bionic scaffolds in bone defects repair. In addition, many technologies and methods as well as issues worthy of special consideration for preparing chirality-induced bionic scaffolds are also introduced. It is expected that this work can provide inspiring ideas for designing new chirality-induced bionic scaffolds and promote the development of chirality in bone tissue engineering.
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  • 文章类型: Journal Article
    手性聚噻吩(PTh),作为最重要的手性导电聚合物之一,是手性材料中一个新兴的热门话题,在手性传感和分离等领域显示出巨大的应用潜力,不对称催化,chiroptoelectronics,甚至chiro-自旋电子学。本文综述了近10年来手性聚噻吩(PThs)的研究进展,包括合成,属性和应用。主要关注实现手性的方式和手性PThs的光学活性。我们展示了一些例子,其中PThs的手性是由带有点的侧链取代基诱导的,平面,和轴向手性或来自外部手性介质。还包括手性PThs的应用。最后,提供了进一步发展的前景。
    Chiroptical polythiophene (PTh), as one of the most important chiral conductive polymers, is an emerging and hot topic in chiral materials, which shows great application potentials in fields as diverse as chiral sensing and separation, asymmetry catalysis, chiroptoelectronics, and even chiro-spintronics. This review summarizes progress in chiral polythiophenes (PThs) in the past 10 years, including the synthesis, properties and applications. Main focus is placed on the manner in which chirality is implemented and the optical activity of the chiral PThs. We showcase examples in which the chirality of PThs is induced by side chain substituents with point, planar, and axial chirality or arises from external chiral media. Application of chiral PThs is also included. Finally, perspectives for further development are offered.
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  • 文章类型: Journal Article
    由于其可调的纹理特性和手性特征,近年来,手性介孔二氧化硅(CMS)在许多领域得到了广泛的关注,并得到了迅速的发展。在这次审查中,我们概述了制造CMS的合成策略及其主要应用。CMS的属性,包括形态学和介孔结构和对映体过量(ee),可以根据合成过程中的合成条件来改变。尽管处于初级阶段,CMS在许多领域引起了广泛的关注。特别是,CMS纳米颗粒广泛用于手性化合物的对映选择性拆分和吸附,具有理想的分离能力。此外,CMS作为有效递送手性或非手性药物以产生手性响应方式的有希望的候选物。此外,CMS在色谱分离和不对称催化中也起着重要作用。对CMS的合成方法和机理进行了深入的综述。本文旨在深入了解CMS的合成和应用,尤其是近年来,并强调了它在未来可能具有的意义。
    Because of its tunable textural properties and chirality feature, chiral mesoporous silica (CMS) gained significant consideration in many fields and has been developed rapidly in recent years. In this review, we provide an overview of synthesis strategies for fabricating CMS together with its main applications. The properties of CMS, including morphology and mesostructures and enantiomer excess (ee), can be altered according to the synthetic conditions during the synthesis process. Despite its primary stage, CMS has attracted extensive attention in many fields. In particular, CMS nanoparticles are widely used for enantioselective resolution and adsorption of chiral compounds with desirable separation capability. Also, CMS acts as a promising candidate for the effective delivery of chiral or achiral drugs to produce a chiral-responsive manner. Moreover, CMS also plays an important role in chromatographic separations and asymmetric catalysis. There has been an in-depth review of the synthetic methods and mechanisms of CMS. And this review aims to give a deep insight into the synthesis and application of CMS, especially in recent years, and highlights the significance that it may have in the future.
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  • 文章类型: Journal Article
    Aryloxyphenylpiperazinylpropanols are a group of compounds exhibiting a wide range of biological activities, affecting the central nervous system and many cardiovascular mechanisms among them. As cardiovascular agents, aryloxyphenylpiperazinylpropanols work as antihypertensives, antiarrhythmics, cardiotonics or antiaggregants. The mechanism of action is almost always an α1-adrenolytic or combined α1- and β-adrenolytic effect, but sometimes other mechanisms (e.g., Ca2+ antagonism or phosphodiesterase inhibition) can positively participate. In some cases, compounds with a small modification of the connecting chain also exhibit the desired cardiovascular effects. Several studies dealt with chirality of aryloxyphenylpiperazinylpropanols and determined the differences between the particular activities of racemic and enantiomeric compounds.
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  • 文章类型: Journal Article
    The furo [2,3-b] indoline ring system is one of the most important structural units in various natural products. It has been known to have inherent biological activities and is utilized as a synthetic target for a number of natural compounds; therefore, this has contributed to a great demand for the growth of synthetic methods for this ring system. Most important compounds with furoindoline ring system are physovenine, madindoline A and B and makomotindoline etc. These compounds are well known to exhibit biological activity against different diseases such as glaucoma, cancer, cachexia, Castleman\'s disease, rheumatoid arthritis, etc. The current article focuses on various synthetic approaches for furoindoline containing compounds and essential furoindoline moiety, such as oxindole-5-O-tetrahydropyranyl ether route etc., and various other diastereoand enantio- controlled approach in a very concise way.
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  • 文章类型: Journal Article
    Nanomaterials with intrinsic enzymatic activity are often referred to as nanozymes. They exhibit many advantages over natural enzymes such as temporal and thermal stability, recyclability, controllable activity, and ease of large-scale preparation. Many efforts have been made in the past 5 years in order to improve their specificity for chiral substrates. This review (with 74 refs.) summarizes the state of the art in the design of nanozymes with chiral selectivity. Following an introduction into nanozymes and chiral selectivity in general, a first large section covers nanozymes based on the use of chiral chemicals. The next two sections describe nanozymes using amino acids and DNA as chiral ligands. A table summarizes the kinetic and selectivity parameters of the currently known chiral enzyme mimics. A concluding section addresses current challenges, and gives perspectives and an outlook on trends. Graphical abstract Chiral nanozymes exhibit the ability of asymmetric catalysis and enantioselective discrimination by modifying with chiral ligands.
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  • 文章类型: Journal Article
    在药物等许多领域使用的纳米材料需要进行毒性评估,电子,杀虫剂,服装和建筑材料。通常影响化学品毒性的一个因素是手性。本文回顾了纳米粒子中手性的存在,并批判性地分析了手性对纳米粒子毒理学风险评估的影响。手性和光学活动源于缺乏对称性,其中对象在其镜像上不可叠加。旋光异构体或对映体具有相似的物理化学性质,但仅在它们的光学活性和它们与生物系统的相互作用方面不同。手性不仅限于有机分子,而且还存在于无机化合物和晶体中。研究还表明,手性分子的吸附可以赋予纳米颗粒手性,并通过仔细设计晶体来暴露手性扭结和阶梯状表面结构。正如手性已经被证明会影响常规化学品的生物活性一样,用不同对映体官能化的纳米颗粒已被证明具有对映选择性和不同的毒性。然而,目前,对配体和在NP中发生手性的条件进行了更多的研究,以及NP手性对蛋白质吸附动力学和热力学的影响。然而,这个粗略的分析显示了手性对纳米粒子生物活性的重要性。在纳米材料(内在或外在)中可能存在手性的情况下,可能需要充分考虑手性的影响。
    Toxicity assessments are required for nanomaterials which are being used in many fields such as medicines, electronics, pesticides, clothes and construction materials. One factor that usually affects toxicity of chemicals is chirality. This paper reviews the existence of chirality in nanoparticles and critically analyses the implications of chirality on toxicological risk assessment of nanoparticles. Chirality and optical activity arise from lack of symmetry, where an object is non-superimposable on its mirror image. Optical isomers or enantiomers have similar physico-chemical properties but only differ in their optical activity and their interaction with biological systems. Chirality is not limited to organic molecules, but also exists in inorganic compounds and crystals. Studies have also shown that chirality can be bestowed onto nanoparticles by adsorption of chiral molecules, and by careful design of the crystal to expose chiral kinked and stepped surface structures. Just as chirality has been shown to affect the biological activities of conventional chemicals, nanoparticles functionalised with different enantiomers have been shown to exhibit enantioselectivity and different toxicities. However, at the moment more studies on the ligands and the conditions under which chirality occurs in NPs, as well as on the effects of NP chirality on protein adsorption kinetics and thermodynamics. Nevertheless, this cursory analysis has shown the importance of chirality on biological activity of nanoparticles. In cases where there is a potential for the existence of chirality in nanomaterials (either intrinsic or extrinsic), there may be need for adequate consideration of the effects of chirality.
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  • 文章类型: Journal Article
    Quantum dots (QDs) are one of emerging engineering nanomaterials (NMs) with advantageous properties which can act as candidates for clinical imaging and diagnosis. Nevertheless, toxicological studies have proved that QDs for better or worse pose threats to diverse systems which are attributed to the release of metal ion and specific characteristics of nanoparticles (NPs), hampering the wide use of QDs to biomedical area. It has been postulated that mechanisms of toxicity evoked by QDs have implications in oxidative stress, reactive oxygen species (ROS), inflammation and release of metal ion. Meanwhile, DNA damage and disturbance of subcellular structures would occur during QDs treatment. This review is intended to conclude the cytotoxicity of QDs in multiple systems, as well as the potential mechanisms on the basis of recent literatures. Finally, toxicity-related factors are clarified, among which chirality seems to be a newly proposed influence factor that determines the destiny of cells in response to QDs. However, details of interaction between QDs and cells have not been well elucidated. Given that molecular mechanisms of QDs-induced toxicity are still not clearly elucidated, further research should be required for this meaningful topic.
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