Recent advances in the synthesis of well-defined glycopolymers

Glycopolymers are receiving increasing interest due to their application in areas, such as glycomics, medicine, biotechnology, sensors, and separation science. Consequently, new methods for their synthesis are constantly being developed, with an increasing emphasis on the preparation of well-defined polymers and on the production of complex macromolecular architectures such as stars. This review covers recent developments in the synthesis of glycopolymers, with a particular emphasis on (i) the use of controlled radical polymerization to prepare well-defined glycopolymers from unprotected monomers and (ii) postpolymerization modification strategies using reactive polymer precursors (including “click” reactions). Recent work on the production of glycosylated polypeptides, which are under investigation as mimics of naturally occurring glycoproteins, is also included. The authors offer some suggestions as to future developments and remaining challenges in this topical area of polymer chemistry. © 2007 Wiley Periodicals, Inc. J Polym Sci PartA: Polym Chem45: 2059–2072, 2007     

2-氧代-2-[(2-氯-5-吡啶甲氨基)(芳基)甲基]-4-芳基-5,5-二甲基-1,3,2-二氧膦杂环己烷的合成及其生物活性研究

通过类Mannich 反应“一锅法”合成了10个未见文献报道的含吡啶基的环状α-氨基膦酸酯, 其结构经¹H NMR, ³¹P NMR, IR, MS和元素分析确证. 测定了该系列化合物的杀虫、杀菌和除草活性, 结果表明, 所测化合物的杀虫活性不太好, 但所有化合物在药液浓度为1.0×10^－4 g/mL 时都具有较好的除草活性, 部分化合物在5.0×10^－5 g/mL时显示出良好的杀菌活性.     

食物中的钼与人体健康

综述了食物中钼与人体健康之间的关系.主要包括常见食物中的钼含量,钼在人体中的代谢,钼的生物学功能以及钼对人体健康的影响等.     

镍与生物

镍是一种稀有金属元素，也是动植物和人的必需营养微量元素。本文对镍的生物学功能及对有机体可能造成的损害进行了详细地阐述。     

α-(2-苯并噻唑氧基)烃基膦酸酯的合成性质和生物活性

为探索α-芳(杂 环)磷酸衍生物的生物活性,寻求含磷农药的新母体,合成了十六个未见文献报道的α-(苯并噻唑-2-氧代)烃基膦酸衍生物,所有化合物的结构均IR,HNMR, 元素分析等确证,并对生物活性进行了初步的研究.     

Surface-grafted polystyrene beads with comb-like poly(ethylene glycol) chains: preparation and biological application

We prepared surface-grafted polystyrene (PS) beads with comb-like poly(ethylene glycol) (PEG) chains. To accomplish this, conventional gel-type PS beads (35-75 microm) were treated with ozone gas to introduce hydroperoxide groups onto the surface. Using these hydroperoxide groups, poly(methyl methacrylate) (PMMA, Mn= 22,000-25,000) was grafted onto the surface of the PS beads. The ester groups of the grafted PMMA were reduced to hydroxyl groups with lithium aluminum hydride (LAH). After adding ethylene oxide (EO) to the hydroxyl groups, we obtained the PS-sg-PEG beads, which had a rugged surface and a diameter of 80-150 microm. We could obtain several kinds of the PS-sg-PEG beads by controlling the chain lengths of the grafted PMMA and the molecular weights of the PEG chains. The grafted PEG layer was about 30-50 microm thick, which was verified from the cross-sectioned views of the fluorescamine-labeled beads. These fluorescence images proved that the beads possessed a pellicular structure. Furthermore, we found that the surface-grafted PEG chains had the characteristic property of reducing non-specific protein adsorption on the beads.     

Mixed hybrid bilayer lipid membrane incorporating valinomycin: improvements in preparation and functioning

The paper deals with the reconstruction of lipid bilayer membranes on a Au-covered polycarbonate membrane. Such a kind of like-biomembranes (namely mixed hybrid bilayer lipid membrane (MHBLM)) are characterised by appreciable long-term stability. Here we describe changes that have been made in the geometry of the experimental device in order to avoid artefacts and render membrane reproduction easier. Incorporation of valinomycin was performed to check the membrane and its stability: conductance and membrane potential following the changes of ion concentration were recorded. This new approach permits increase of successful trials and renders possible, when it breaks, easily formation of a new MHBLM on the same Au-covered polycarbonate membrane support. Finally, the stability shown by the MHBLM renders this system a promising tool for use under flowing conditions.     

Novel Water Soluble Fluorescent Trimethine Indocyanines Containing N-ρ-Carboxybenzyl Group

Indocyanine dyes as fluorescent labeling reagents have been used in bioanalysis1,2. Arylsulfonate indocyanine dyes 1d and 1e developed by Waggoner A. S. et al.3,4 have excellent fluorescent properties combined with good aqueous solubility, are a new generation of fluorescent label compounds for proteins, oligonucleotides and other compounds containing hydroxyl, mercaptol or primary amine groups5. However, photostability of these dyes has been a problem. Z. G. YAO et al.6 reported that p…     

哒嗪酮类α1-肾上腺素受体拮抗剂的合成和生物活性研究

将苯(氧)乙胺和苯氧烷胺类α₁-肾上腺素受体拮抗剂中的苯(氧)乙胺、苯氧烷胺片段引入哒嗪酮类化合物中, 设计、合成了30个新的含哒嗪酮环的α₁-肾上腺素受体拮抗剂. 所有新化合物的结构均经¹H NMR, IR, HRMS确证. 生物活性测试表明28个目标物对α₁-肾上腺素受体有较好的拮抗作用(pA₂＞6.00), 化合物6o, 6p, 6q, 6v, 6x, 6y, 10c, 10d的pA₂值＞7.00.