A Self-Replicating Peptide under Ionic Control

The chemical coupling of two peptide fragments to give the peptide K1 K2 (shown in the helical wheel diagram on the right) is autocatalytic at high NaClO₄ concentrations (1 M ). Under these conditions K1 K2 assumes a coiled-coil conformation, which can function as a template for the coupling. Autocatalysis is not observed under conditions that prevent formation of the coiled-coil conformation.     

酰胺类化合物的高效合成研究

酰胺类化合物是有机化学中最常见的化合物之一, 在药物化学、生物化学以及高分子合成等领域都有着重要的应用. 近年来高效合成酰胺类化合物已经成为一个研究热点, 具有重要的意义.本文主要从过渡金属催化、有机小分子催化等方面讨论近几年来酰胺类化合物的合成研究进展, 并对其发展趋势进行展望.     

天然山奈酚5位鼠李糖糖苷的高效合成

Kaempferol-5-O-α-L-rhamnopyranoside(1)与Kaempferol-3,5-di-O-α-L-rhamnopyranoside(2)是一类具有代表性的黄酮醇5位鼠李糖的天然化合物.由于5位羟基具有较强的分子内氢键,传统的糖苷化条件不能高效合成.本工作使用全新的糖苷化方法,以糖基邻炔基苯甲酸酯作给体,一价金作催化剂,高效的构建了山奈酚5位的糖苷键,并完成了天然产物1和2的合成.     

Highly Efficient Synthesis of Novel Poly-aza Bis-histidines

A series of novel poly-aza bis-histidines with much potential in medicinal, bioinorganic, bioorganic, biomimetic and supramolecular chemistry were synthesized conveniently, efficiently and readily in excellent yields from commercial histidine. The low temperature in the reaction of the protected histidine with poly-aza diamine 5 is key condition for the selective preparation of target compounds with high yields.     

双酚A葡萄糖醛酸苷的高效制备

采用鼠肝微粒体(RLM)生物转化法,利用正交实验在体外实现了双酚A(BPA)向双酚A葡萄糖醛酸苷(BPA-G)的高效转化,同时借助新型色谱分离材料C18WAX及固相萃取技术实现了BPA-G的高效富集与纯化,并对产物进行了结构表征.     

三种天然脱氧核苷的高效合成

本文以1-氯-2-脱氧-α-3,5-二-O-(对氯苯甲酰基)呋喃核糖(1)(以下简称氯代糖)为原料, 开发出可以适用于大规模工业生产的简单、 高效的合成上述三种天然核苷路线.     

CompassR Yields Highly Organic-Solvent-Tolerant Enzymes through Recombination of Compatible Substitutions

The CompassR (computer-assisted recombination) rule enables, among beneficial substitutions, the identification of those that can be recombined in directed evolution. Herein, a recombination strategy is systematically investigated to minimize experimental efforts and maximize possible improvements. In total, 15 beneficial substitutions from Bacillus subtilis lipase A (BSLA), which improves resistance to the organic cosolvent 1,4-dioxane (DOX), were studied to compare two recombination strategies, the two-gene recombination process (2GenReP) and the in silico guided recombination process (InSiReP), employing CompassR. Remarkably, both strategies yielded a highly DOX-resistant variant, M4 (I12R/Y49R/E65H/N98R/K122E/L124K), with up to 14.6-fold improvement after screening of about 270 clones. M4 has a remarkably enhanced resistance in 60 % (v/v) acetone (6.0-fold), 30 % (v/v) ethanol (2.1-fold), and 60 % (v/v) methanol (2.4-fold) compared with wild-type BSLA. Molecular dynamics simulations revealed that attracting water molecules by charged surface substitutions is the main driver for increasing the DOX resistance of BSLA M4. Both strategies and obtained molecular knowledge can likely be used to improve the properties of other enzymes with a similar α/β-hydrolase fold.     

The Highly Controlled and Efficient Polymerization of Ethylene

The highly controlled and efficient polymerization of ethylene is a very attractive but challenging target. Herein we report on a Coordinative Chain Transfer Polymerization catalyst, which combines a high degree of control and very high activity in ethylene oligo- or polymerization with extremely high chain transfer agent (triethylaluminum) to catalyst ratios (catalyst economy). Our Zr catalyst is long living and temperature stable. The chain length of the polyethylene products increases over time under constant ethylene feed or until a certain volume of ethylene is completely consumed to reach the expected molecular weight. Very high activities are observed if the catalyst elongates 60 000 or more alkyl chains and the polydispersity of the strictly linear polyethylene materials obtained are very low. The key for the combination of high control and efficiency seems to be a catalyst stabilized by only one strongly bound monoanionic N-ligand.     

Extended Thienylenevinylene Oligomers as Highly Efficient Molecular Wires

A much smaller band gap than in the parent polymer is observed for the π-conjugated hexadecamer 1 , which can be reversibly charged up to the hexacation in a small potential range.     

A Highly Efficient Macrolactonization Method via Ethoxyvinyl Ester

Facile and efficient macrolactonization of hydroxycarboxylic acid via ethoxyvinyl esters (EVEs), which can give 9‐ to 14‐membered macrolactones in good yields, has been developed (see scheme; DCE = 1,2‐dichloroethane). The method is useful for acid‐/base‐sensitive substrates and applicable to the compound with many functional groups.

     

Highly Efficient Phase Boundary Biocatalysis with Enzymogel Nanoparticles

The enzymogel nanoparticle made of a magnetic core and polymer brush shell demonstrates a novel type of remote controlled phase‐boundary biocatalysis that involves remotely directed binding to and engulfing insoluble substrates, high mobility, and stability of the catalytic centers. The mobile enzymes reside in the polymer brush scaffold and shuttle between the enzymogel interior and surface of the engulfed substrate in the bioconversion process. Biocatalytic activity of the mobile enzymes is preserved in the enzymogel while the brush‐like architecture favors the efficient interfacial interaction when the enzymogel spreads over the substrate and extends substantially the reaction area as compared with rigid particles.     

高效率有机太阳能电池的界面工程研究

有机太阳能电池(OSC)为典型的三明治结构,是以共轭类有机化合物为活性层材料将太阳光转换为电能,通过两个电极输出电流。这些有机物具有来源广、质量轻和可再生等优点,使得有机太阳能电池在清洁新能源领域备受关注。当前研究的焦点仍然是提高电池的光电转换效率,主要通过改善活性层材料、优化器件结构和界面修饰等途径。本文重点介绍了作者课题组在界面工程方面所做的代表性工作,通过引入含磺酸基团或羧酸基团的超支化结构的聚合物阴极修饰层材料,获得了高效的OSCs;合成了新颖的非共轭有机小分子电解质修饰层,制备了高达10.02%效率的单结正型OSCs。此外,还研究了简单的极性溶剂处理,如甲醇能够优化活性层形貌,提高电池器件的性能。