抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

Molecular self-assembly is the spontaneous association of molecules under equilibrium conditions into stable, structurally well-defined aggregates joined by noncovalent bonds. Molecular self-assembly is ubiquitous in biological systems and underlies the formation of a wide variety of complex biological structures. Understanding self-assembly and the associated noncovalent interactions that connect complementary interacting molecular surfaces in biological aggregates is a central concern in structural biochemistry. Self-assembly is also emerging as a new strategy in chemical synthesis, with the potential of generating nonbiological structures with dimensions of 1 to 10(2) nanometers (with molecular weights of 10(4) to 10(10) daltons). Structures in the upper part of this range of sizes are presently inaccessible through chemical synthesis, and the ability to prepare them would open a route to structures comparable in size (and perhaps complementary in function) to those that can be prepared by microlithography and other techniques of microfabrication.

Molecular self-assembly and nanochemistry: A chemical strategy for the synthesis of nanostructures

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Cucurbituril-Based Molecular Recognition.

Metal-organic framework (MOF) nanoparticles, also called porous coordination polymers, are a major part of nanomaterials science, and their role in catalysis is becoming central. The extraordinary variability and richness of their structures afford engineering synergies between the metal nodes, functional linkers, encapsulated substrates, or nanoparticles for multiple and selective heterogeneous interactions and activations in these MOF-based nanocatalysts. Pyrolysis of MOF-nanoparticle composites forms highly porous N- or P-doped graphitized MOF-derived nanomaterials that are increasingly used as efficient catalysts especially in electro- and photocatalysis. This review first briefly summarizes this background of MOF nanoparticle catalysis and then comprehensively reviews the fast-growing literature reported during the last years. The major parts are catalysis of organic and molecular reactions, electrocatalysis, photocatalysis, and views of prospects. Major challenges of our society are addressed using these well-defined heterogeneous catalysts in the fields of synthesis, energy, and environment. In spite of the many achievements, enormous progress is still necessary to improve our understanding of the processes involved beyond the proof-of-concept, particularly for selective methane oxidation, hydrogen production, water splitting, CO2 reduction to methanol, nitrogen fixation, and water depollution.

State of the Art and Prospects in Metal-Organic Framework (MOF)-Based and MOF-Derived Nanocatalysis.

The present review is devoted to summarizing the recent advances (2015-2017) in the field of metal-catalysed group-directed C-H functionalisation In order to clearly showcase the molecular diversity that can now be accessed by means of directed C-H functionalisation, the whole is organized following the directing groups installed on a substrate Its aim is to be a comprehensive reference work, where a specific directing group can be easily found, together with the transformations which have been carried out with it Hence, the primary format of this review is schemes accompanied with a concise explanatory text, in which the directing groups are ordered in sections according to their chemical structure The schemes feature typical substrates used, the products obtained as well as the required reaction conditions Importantly, each example is commented on with respect to the most important positive features and drawbacks, on aspects such as selectivity, substrate scope, reaction conditions, directing group removal, and greenness The targeted readership are both experts in the field of C-H functionalisation chemistry (to provide a comprehensive overview of the progress made in the last years) and, even more so, all organic chemists who want to introduce the C-H functionalisation way of thinking for a design of straightforward, efficient and step-economic synthetic routes towards molecules of interest to them Accordingly, this review should be of particular interest also for scientists from industrial R&D sector Hence, the overall goal of this review is to promote the application of C-H functionalisation reactions outside the research groups dedicated to method development and establishing it as a valuable reaction archetype in contemporary R&D, comparable to the role cross-coupling reactions play to date

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A comprehensive overview of directing groups applied in metal-catalysed C-H functionalisation chemistry.

Metal–organic frameworks with catalytic centers: From synthesis to catalytic application

Twisted Cucurbit[14]uril

Five new metal complexes, [Zn3(L1)2(BTC)2]·6H2O (1), [Zn3(L1)(BTC)2] (2), [Cd3(L1)(BTC)2] (3), [Cd3(L2)(BTC)2]·4H2O (4), and [Cd3(L2)(BTC)2(H2O)2] (5), have been successfully synthesized by solvothermal reactions of corresponding metal salts with 1,3,5-benzenetricarboxylic acid (H3BTC) and imidazole-containing ligands 1,3,5-tris(imidazol-1-ylmethyl)benzene (L1) and 3,3′,5,5′-tetra(imidazol-1-yl)-1,1′-biphenyl (L2). The structures of the complexes were determined by single crystal X-ray diffraction analysis. Complexes 1 and 2 obtained at different reaction temperatures show different structures: 1 is a three-dimensional (3D) net with Zn-BTC3– layers pillared by L1 ligands, while 2 has a 3D structure with a Zn-BTC3– framework and Zn-L1 chain. Complexes 2 and 3, which contain different metal centers, have similar framework structures but different coordination modes of carboxylate groups. 4 and 5 that were prepared from different solvents show different 3D structures. The thermal stability, photoluminescence...

Zinc(II) and Cadmium(II) Complexes with 1,3,5-Benzenetricarboxylate and Imidazole-Containing Ligands: Structural Variation via Reaction Temperature and Solvent

Twisted Cucurbit[n]urils.

Ferroelectricity is one of major subjects in the field of materials science owing to its wide applications in ferroelectric random-access memories (FeRAMs) and tunable microwave devices. In previous reports, considerable research on ferroelectric materials was devoted to inorganic compounds such as NaKC4H4O6·4H2O [3] and perovskite-like oxides. Recently, molecule-based ferroelectric materials have received much attention owing to features distinctive from those of inorganic materials. For example, molecule-based complexes are easily polarized in an applied field because of polar groups in the organic ligands. Neutral mononuclear molecule-based ferroelectric materials can be more conveniently evaporated at low temperature than ionic inorganic compounds for the preparation of memory devices by chemical vapor deposition (CVD) methods. Consequently, the fabrication process is more controllable and the precursor molecule is not decomposed, which results in the retention of molecular structure in the resulting films. As donor or acceptor dopants, lanthanide cations have typically been used to modify the properties of ferroelectrics such as lead zirconium titanate (PZT) for achieving high Pr (remnant polarization) values, square hysteresis loops, and enhanced fatigue resistance. However, to the best of our knowledge, there are no reports on lanthanide-containing complexes in molecule-based ferroelectrics. In our work, two chiral 2,2’-bipyridine derivatives (LR,R= ( )-4,5-pinene bipyridine and LS,S= (+)-4,5-pinene bipyridine; see Scheme S1 in the Supporting Information) were prepared, and their coordination to [Eu(tta)3]·2H2O was investigated (tta= 2thenoyltrifluoroacetonate). Subsequently, the neutral enantiomeric pair 1 and 2 with the formula [Eu(tta)3L] (L=LR,R for 1 and LS,S for 2) and a C2 polar point group were successfully synthesized, and they are among the simplest hybrid organic–inorganic ferroelectric materials. Furthermore, hybrid organic–inorganic ferroelectric thin films were prepared by CVDmethods for the first time. Reported herein is a detailed description of the synthesis, crystal structures, and ferroelectric and dielectric properties of 1 and 2. Pale red crystals of 1 and 2 were obtained by slow evaporation over a period of three weeks of an acetone/ ethanol solution containing [Eu(tta)3]·2H2O and the respective chiral 2,2’-bipyridine derivative. X-ray analysis revealed that the two complexes are enantiomers and their properties are similar, and hence only the results of 1 are given in the ensuing discussion (Figure 1). Complex 1 is a mononuclear neutral europium(III) complex. As shown in Figure 1, each molecule contains three b-diketonate anions, a chiral 2,2’bipyridine derivative, and an eight-coordinate Eu cation.

Kai Chen

Papers

Metal–organic frameworks with catalytic centers: From synthesis to catalytic application

Twisted Cucurbit[14]uril

Zinc(II) and Cadmium(II) Complexes with 1,3,5-Benzenetricarboxylate and Imidazole-Containing Ligands: Structural Variation via Reaction Temperature and Solvent

Twisted Cucurbit[n]urils.

Molecule‐Based Ferroelectric Thin Films: Mononuclear Lanthanide Enantiomers Displaying Room‐Temperature Ferroelectric and Dielectric Properties