无溶剂条件下碘催化不对称双吲哚的合成

在室温以及无溶剂条件下,吲哚与烷基-3-吲哚基甲醇在碘的催化下以73％～99％的高收率得到不对称双吲哚烷基化合物。其结构经^1H NMR,IR及MS表征。     

酸度调控的3,3-二乙硫基丙烯酸酯的吲哚化反应

探讨了酸度调控的3,3-二乙硫基丙烯酸酯的吲哚化反应,选择性地合成3,3-二吲哚基丙烯酸酯和3-吲哚基-3-氧代丙酸酯.研究表明,3,3-二乙硫基丙烯酸酯与吲哚反应时,在稀酸条件下,高产率生成3,3-二吲哚基丙烯酸酯,而在浓酸条件下,生成的3-吲哚基-3-乙硫基丙烯酸酯不稳定,在后处理和柱层析分离时易水解,高产率得到3-吲哚基-3-氧代丙酸酯.     

铜催化加成/取代串联反应构建四取代的三吲哚甲烷

在温和的条件下,利用3-乙酰基吲哚与吲哚的加成/取代串联反应,高效地合成了一系列高度拥挤的四取代三吲哚甲烷.该方法通过在3-乙酰基吲哚的氮原子上引入吸电子基团,提高了3-乙酰基吲哚的反应活性,具有原料廉价易得、底物适用性广、操作简便等优点.     

吲哚美辛的毛细管电泳测定法研究

建立了制剂和体液中吲哚美辛的毛细管电泳高频电导分析法,并用于吲哚美辛肠溶片、复方吲哚美辛酊及血清、尿液中吲哚美辛含量的测定。对电泳介质的种类、浓度以及操作电压和进样量等影响因素进行了优化。实验采用3.0mmol／L乳酸＋0．68mol／L乙醇为电泳介质,分离电压为20.0kV,可在10min内实现对吲哚美辛的分离检测。在最佳实验条件下,吲哚美辛的线性范围为0.05μg／mL—100μg／mL,检出限为0．01μg／mL,回收率92.0％-105．1％。     

2-吲哚酮和5-甲基-2-吲哚酮的无溶剂法制备

以苯胺和氯乙酰氯为原料在NaOH存在下酰化合成N-氯乙酰基苯胺,然后N-氯乙酰基苯胺在无水AICI,催化下环化合成2-吲哚酮．对由N-氯乙酰基苯胺合成2-吲哚酮的工艺条件进行了改进．结果表明合成2-吲哚酮的最佳条件为：反应温度为220℃,反应时间为60min,加料时温度为180℃,N-氯乙酰基苯胺与氯化钠,无水AlCl3的重量比为1：1：5．5．改进后的合成2-吲哚酮收率达到88．3％,纯度99％,收率比原工艺提高了24．6％．在此基础上,还合成了5-甲基-2-吲哚酮,并得到其最佳条件为：反应温度为190℃,反应时间为30min,加料时温度为180℃,4-甲基-N-氯乙酰基苯胺与氯化钠,无水AlCl3的重量比为1：1：5．5,收率达到83．1％,纯度为99％．     

自支撑柔性聚(5-吲哚硼酸)膜的电化学合成及表征

在三氟化硼乙醚/乙腈的混合体系中,5-吲哚硼酸的电化学氧化可以获得导电率为9×10-4 S·cm-1的自支撑柔性聚(5-吲哚硼酸)膜.5-吲哚硼酸在80％的三氟化硼乙醚亿腈溶液中的起始氧化电位约为0.80V红外光谱确定了5-吲哚硼酸的聚合位点在C2和C3位上.紫外可见光谱测试结果表明聚(5-吲哚硼酸)的能隙约为2.48...     

碘作用下吲哚3位硫醚化反应

本文发展了碘作用下吲哚及其衍生物与芳香族硫醇类化合物的直接硫醚化反应,在吲哚3位形成C-S键。在温和的反应条件下,多种杂环硫醇能够与吲哚反应高产率地得到3位硫醚化合物。     

铜催化加成/取代串联反应构建四取代的三吲哚甲烷（英文）

在温和的条件下,利用3-乙酰基吲哚与吲哚的加成/取代串联反应,高效地合成了一系列高度拥挤的四取代三吲哚甲烷.该方法通过在3-乙酰基吲哚的氮原子上引入吸电子基团,提高了3-乙酰基吲哚的反应活性,具有原料廉价易得、底物适用性广、操作简便等优点.     

褪黑激素的合成

以5－甲氧基吲哚为起始原料，经4步反应合成了褪黑激素（MLT).5－甲氧基吲哚和草酰氯在0℃-5℃定量反应生成5－甲氧基吲哚－3－草酰氯（I），I直接用氨水胺化得98％的5－甲氧基吲哚－3－草酰胺（Ⅱ），Ⅱ用氢化铝锂还原得到5－甲氧基色胺（Ⅲ），收率57％，Ⅲ经乙酰化即得目标产物MLT，收率80％。     

吲哚与亚胺的Friedel-Crafts反应的研究进展

由于吲哚类化合物具有许多生物特性等优点,在众多天然产物和相应的具有生物活性的化合物中起重要的骨架构筑作用,其合成方法的研究格外令人注目.近年来,关于吲哚与亚胺在催化剂作用下发生Friedel-Crafts反应来制备3-取代吲哚甲胺衍生物的报道剧增.对近年来吲哚与亚胺Friedel-Crafts反应的研究情况进行了综述.     

Calibration methods for microdialysis sampling in vivo: muscle and adipose tissue

Calibration methods for microdialysis sampling were studied in the muscle and adipose tissue of rats. Both the delivery method and the no-net-flux method were used to determine the extraction efficiency (EE) of acetaminophen and caffeine in both tissues. There was no concentration dependence of the EE either in vitro or in vivo for either acetaminophen or caffeine. The EEs determined by the delivery and no-net-flux methods were not different. However, the EEs of both caffeine and acetaminophen determined in vitro were significantly higher than those determined in the muscle and adipose. This indicates that mass transfer in the tissue is the rate-determining factor for the EE in vivo. The relative difference between the EE in vitro and the EE in the muscle was smaller than the difference between the EE in vitro and the EE in the adipose. In addition, the EE in the muscle decreased more than the EE in the adipose after the animal was euthanized. This indicated that exchange between the extracellular fluid and plasma is the rate-determining step in mass transport relative to microdialysis sampling. This has a more significant effect on the EE in the muscle than the EE in the adipose. Both the delivery and no-net-flux methods can be used to calibrate microdialysis probes in the muscle and adipose.     

延边地区65～108岁健康老人头发中锌、铜、铁、锰、镁的含量

用原子吸收光谱法测定延边地区317名65～108岁老人头发中锌、铜、铁、锰、镁含量，观察不同民族、性别、年龄老人这些元素的差异。结果表明：1.朝鲜旗发锌低于汉族，满族发铜低于汉族、朝鲜族，汉族发镁高于朝鲜族、满族，发铁、发锰在汉、朝、满民族之间无区别。2．汉族、朝鲜族男发锌高于女性，汉族女性发铜高于男性，发铁、发锰、发镁在性别之间无区别。3、90岁组朝鲜族发锰、发镁低于65岁、76岁组，朝鲜族发锌、发铜、发铁在65～108岁之间无统计学意义。     

Effects of dilute acid and steam explosion pretreatments on the cellulose structure and kinetics of cellulosic fraction hydrolysis by dilute acids in lignocellulosic materials

Worldwide, yellows diseases impact plants important in human nutrition, the natural environment, and the culture and commerce of humans. Since the presumed pathogens, mycoplasma-like organisms (MLOs), have not been isolated in pure culture in vitro, their study must proceed by other experimental approaches. In a study of disease affecting grapevines in Europe and North America, polymerase chain reactions (PCR) and restriction analyses of PCR-amplified DNA were used to detect and differentiate strains of MLOs associated with grapevine yellows. MLOs were detected both in naturally diseased grapevines and in experimentally inoculated host plants. The data indicated an unexpected genomic diversity among grapevine-infecting MLOs, and supported their classification with MLOs in the aster yellows, X-disease, and elm yellows groups. The presence of diverse MLOs in grapevines provokes consideration that these MLOs may be present in overlapping geographic ranges and that multiple MLO infections may occur in individual plants, increasing the complexity of grapevine yellows epidemiology and control and the significance of sensitive MLO detection in planting stock and phytosanitary-regulated germplasm.     

青藏高原湖泊影响锂元素迁移和富集的矿物、元素及环境因素——以西藏郭扎错钻孔沉积物为例

作为我国战略性矿产的锂矿,主要赋存于青藏高原盐湖中。湖泊系统中,锂的富集和迁移规律关系到锂矿的高效提取和未来锂矿的储量估算。本文以西藏咸水湖郭扎错的钻孔沉积物为例,结合AMS14C年代和Mg元素含量变化,系统分析了孔隙水、碳酸盐矿物和硅酸盐矿物的锂含量变化,探讨了矿物、镁元素、环境变化和早期成岩作用等对锂元素迁移和富集的影响。郭扎错沉积物中锂和镁大部分存在于硅酸盐矿物中,锂和镁较高的相关性说明二者存在于相同的硅酸盐矿物中,如粘土矿物。大约90%的锂赋存在硅酸盐矿物中,约8.5%的锂赋存在碳酸盐矿物中,孔隙水中的锂含量占比仅约1.5%。碳酸盐矿物中Mg/Li摩尔比值为78–270,是孔隙水中10多倍,而硅酸盐矿物中的Mg/Li摩尔比值稳定在24–29之间。水–沉积物相互作用促进硅酸盐矿物中锂的释放,咸水环境下释放的锂多于淡水环境下。碳酸盐矿物中,锂和镁主要存在于方解石中。镁离子对锂离子的迁移具有阻碍作用,低温、高盐度下的阻碍作用更强。湖泊沉积物可能是湖水锂的一个重要来源。     

Effect of the displacement reaction on the composition of the magnetic layer in electrodeposited layered nanostructures Co-Cu/Cu and Ni-Cu/Cu

Methods of stripping voltammetry, quartz microgravimetry, and x-ray-fluorescence analysis are employed to explore the copper displacement process on thin electrodeposited layers of pure cobalt and nickel and on deposits of these metals with inclusions of copper. The displacement reaction proceeds at a considerable rate on cobalt in the sulfate and sulfosalicylate solutions and virtually does not proceed on nickel in both the sulfate or sulfate-chloride solutions. An estimate of the rate of the copper displacement reaction following a change in the concentration of copper ions in the solution and in the pH of the sulfosalicylate solution is given. A decrease in the contact exchange rate is facilitated by a decrease in the concentration of copper ions in solution and their participation in the formation of complexes.     

Analytical strategies to determine antibiotic residues in fish

The accelerated growth of aquaculture has resulted in a series of harmful effects to human health. The widespread and unrestricted use of antibiotics in this industry, to prevent bacterial infections, leads to remaining amounts in the aquatic environment. This has resulted in the emergence of antibiotic-resistant bacteria in aquaculture environments, in the increase in antibiotic resistance in fish pathogens as well as in the transfer of these resistance determinants to human pathogens. Moreover, the use of large amounts of antibiotics may lead to the presence of residual antibiotics in fish tissue and fish products. Fluoroquinolones, tetracyclines, penicillins, sulphonamides and other antibiotics, exhibiting activity against both Gram-positive and Gram-negative bacteria, are widely used for the treatment and prevention of diseases in fish. An extended and comprehensive review on the recent analytical methodologies concerning antibiotic residues in fish reported in the literature is provided in the present article. Emphasis is given on sample preparation regarding isolation and purification, chromatographic conditions and method validation according to legislation. Results of published assays are comparatively presented and criticised.     

The conductance of bile salt-lecithin-water mixtures

The conductance of aqueous solutions of sodium glycodeoxycholate and sodium taurodeoxycholate displays a complex concentration dependence (0–0.5 C) with a maximum and minimum occurring in dilute solutions. This behavior can be related to physiologic concentrations observed in hepatic and gallbladder bile and interpreted in terms of anion dimerization and ultimately micellization. The addition of lecithin in 1:2 or 1:5 molar ratios results in micellization at lower concentration, disappearance of the maximum and minimum in the conductance curve, and a decrease in the total conductance.     

GC-MS analysis of penta- and tetra-cyclic triterpenes from resins of Pistacia species. Part II. Pistacia terebinthus var. Chia

Pistacia species contain oleoresins with bioactive triterpenes. In this study triterpenes, including minor components, were identified and quantified in both neutral and acidic fractions of Pistacia terebinthus var. Chia resin, grown exclusively in Chios island (Greece), collected traditionally, as well as using stimulating agents (liquid collection). It was proved that these two resin samples were composed of several different minor triterpenes, while major constituents were similar but in different proportions. Compounds that differentiated two resin samples of P. lentiscus and P. terebinthus var. Chia, both traditionally collected, were detected, in order to identify the nature of resins present in archaeological materials. In the traditionally collected resin, 37 triterpenes were identified, 12 in the acidic and 25 in the neutral fraction. In the liquid collection resin 10 compounds were identified in the acidic and 23 in the neutral fraction, while 16 compounds were not contained in the traditionally collected resin. The main triterpenes in both resin samples collected traditionally and using stimulating agents were: isomasticadienonic acid (23.6 and 26.3% w[sol ]w of the triterpenic fraction, respectively), 28-norolean-17-en-3-one (16.3 and 17.5% w[sol ]w of the triterpenic fraction, respectively) and masticadienonic acid (5.8 and 6.0% w[sol ]w of the triterpenic fraction). In this study the qualitative and quantitative composition of triterpenes was compared in the Pistacia lentiscus and P. terebinthus var. Chia resin samples collected with the traditional and new liquid techniques, and also triterpenes in resins of P. terebinthus obtained by the traditional technique and using stimulating agents. The aim of the study was also to examine whether the collection technique influenced the triterpenes contained in P. terebinthus var. Chia resin samples.     

Comparison of Photochemical Reactions of m-Cresol in Aqueous Solution and in Ice

We compared the photochemical reaction of m-cresol containing OH precursors such as H₂O₂, NO₂^- and NO₃^- in aqueous solution with those in ice. The results show that the conversion rate of m-cresol in aqueous solution was higher than that in ice. H₂O₂, NO₂^- and NO₃^- all accelerated the photoconversion of m-cresol in both aqueous solution and ice. The photochemical reactions of m-cresol obeys the first order kinetics equation. According to the photoproducts identified by GC-MS, we proposed that hydroxylation and nitration reactions occurred in both aqueous solution and ice. Coupling reaction was common in ice, however, in aqueous solution it was found only in UV system. Our results suggest that the photochemical reactions of m-cresol were different in aqueous solution and in ice.     

Butyltin compounds in severn sound,lake huron,canada

Severn Sound is a heavily used recreational and beating area in the southeast corner of Georgian Bay, Lake Huron, Canada. Because of the concern over the possible release of tributyltin species (TBT) from antifouling paints on boat hulls and marinas, surveys were carried out in 1989 and 1992 to determine the presence of this species and its degradation products dibutyltin (DBT) and monobutyltin (MBT) in this area. Many fish (pike and young–of–the–year spottail shiners) and sediment samples collected in 1989 contained detectable levels of TBT. A maximum concentration of TBT was recorded in northern pike in the spring to be 240 ng Sn g^?1. Maximum levels occurred in marinas during the beginning of the boating season and significantly reduced during the summer and early autumn, although the maximum value of TBT in sediment (392 ng Sn g^?1) was observed in the summer of 1989. The seasonal variation of TBT levels was further substantiated in the subsequent 1992 study, in which sediments from three areas in a marina were sampled at monthly intervals from May to October. TBT levels were much higher in May and then generally decreased with time. Mussels (Elliptio complanta) caged in the marina for three months also contained TBT. DBT was frequently detected in the sediments but less frequently in fish and mussels. MBT was generally below detection limits. Plants (macrophytes and cladophora) contained very small amounts of butyltin compounds.