Synthesis and anticancer property of one Fe(II) compound based on 5-(3-pyridyl)tetrazole-2-acetic acid

Abstract

Tetrazole-carboxylate ligands are universally considered as multi-functional candidates for the construction of coordination architectures. A 1-D [Fe(pytza)₂(H₂O)₂]_n·2nH₂O (pytza = 5-(3-pyridyl)tetrazole-acetato) has been prepared. In vitro study on Hela cells show that Hpytza is naturally nontoxic while [Fe(pytza)₂(H₂O)₂]_n·2nH₂O shows high toxicity with a half-maximal inhibitory concentration (IC₅₀) of 6.3?×?10^?5 M. In addition, the compound can effectively inhibit the migration of Hela cells.     

在线富集/高效液相色谱与电感耦合等离子体质谱联用测定玩具中超痕量可迁移六价铬

采用在线富集/高效液相色谱(HPLC)与电感耦合等离子体质谱(ICP-MS)联用技术,建立了玩具中超痕量可迁移六价铬的测定方法。以10mmol/L硝酸铵为流动相,样品在AgilentBIOWAXNP5阴离子交换柱(46mm×50mm,5μm)中富集,再通过阀切换,以75mmol/L硝酸铵将六价铬洗脱至DionexAG7阴离子柱(4.0mm×50mm,10μm)中分离,最后经ICP-MS进行分析。优化得到在线富集时间为4min,进样量为900μL,富集流速为0.4mL/min,洗脱流速为0.6mL/min。结果显示,六价铬在2~20ng/L范围内线性良好,检出限为1.93ng/L,相对标准偏差(RSD)为3.9%。与直接进样相比,浓缩因子约为8.1倍,富集效率约为90%。对欧盟玩具安全指令2009/48/EC规定的3类玩具材料在5、10ng/L的浓度水平下进行加标回收,回收率为93.4%~111%     

Lysophosphatidylglycerol inhibits formyl peptide receptor like-1-stimulated chemotactic migration and IL-1�� production from human phagocytes

In this study, we observed that lysophosphatidylglycerol (LPG) completely inhibited a formyl peptide receptor like-1 (FPRL1) agonist (MMK-1)-stimulated chemotactic migration in human phagocytes, such as neutrophils and monocytes. LPG also dramatically inhibited IL-1β production by another FPRL1 agonist serum amyloid A (SAA) in human phagocytes. However, LPG itself induced intracellular calcium increase and superoxide anion production in human phagocytes. Keeping in mind that phagocytes migration and IL-1β production by FPRL1 are important for the induction of inflammatory response, our data suggest that LPG can be regarded as a useful material for the modulation of inflammatory response induced by FPRL1 activation.     

纺织品与食品包装材料中烷基酚及双酚A迁移量的液相色谱-串联质谱分析

建立了纺织品与食品包装材料中烷基酚及双酚A迁移量的液相色谱-串联质谱分析方法。纺织品和食品包装材料浸泡液经SupelcleanEnvi-Carb石墨化碳黑固相萃取柱净化,以WatersXBridgeC18(150mm×2.1mm,3.5μm)色谱柱分离后,进行LC-MS/MS多反应监测模式下的定性及定量分析。烷基酚和双酚A在纺织品模拟汗液、食品模拟物介质中特定迁移量的定量下限分别为2、4μg/kg。在低、中、高3个添加水平下,测得纺织品样品的回收率为83%⁹1%,相对标准偏差为4.1%⁹.0%;食品包装材料样品的回收率为82%⁹4%,相对标准偏差为3.9%⁸.7%。     

B和N原子掺杂超长(3,3)单壁碳纳米管的从头算研究

用从头算的周期边界条件方法,建立了(3,3)型超长单壁碳纳米管的新模型.使用B3LYP/3-21G方法计算了B和N掺杂纳米管的结构参数、掺杂能量、能带结构以及能隙.研究表明,B和N原子掺杂的(3,3)型单壁碳纳米管具有直接带隙半导体特征,其α轨道计算所得能隙值分别为1.797和2.041 eV.     

Gold(I)‐Catalyzed Regiodivergent Rearrangements: 1,2‐ and 1,2′‐Alkyl Migration in Skipped Alkynyl Ketones

A series of 2‐alkynyl carbonyl compounds that contain a cyclopentene ring or a heterocycle can be transformed into various fused dihydrobenzofurans and tetrahydrofuro[2,3‐c]pyridines by means of a 1,2‐alkyl migration process. Both of these reactions proceed with excellent regioselectivity and stereospecificity when using a cationic gold(I) catalyst. Treatment of 4‐styrylcyclopent‐1‐enecarboxylates under different conditions affords a range of highly functionalized dihydrobenzofurans and dihydroisobenzofurans. A divergence in product selectivity, which depends on the anion of the silver salts used, was observed. Interestingly, ring‐fused tetrahydroquinolines undergo only 1,2′‐alkyl migration reaction by means of a C? C cleavage/cyclization sequence to provide tetrahydroazepine derivatives. Mechanistic studies suggest that the gold complexes catalyze 1,2‐alkyl migration reactions through a concerted reaction pathway and 1,2′‐alkyl migration reactions through a stepwise reaction pathway.     

不同孪晶界密度银纳米线拉伸形变行为的分子动力学模拟

采用分子动力学方法模拟了不同孪晶界密度银纳米线的拉伸形变行为, 分析了孪晶界密度对多晶银纳米线屈服强度、弹性模量和塑性变形机理的影响. 在弹性形变区域, 孪晶界的存在对杨氏模量变化的作用不明显. 在塑性形变阶段, 首先从表面边缘开始产生位错成核, 然后延伸并受阻于孪晶界. 在进一步拉伸载荷作用下, 孪晶界将作为位错源产生新的位错. 模拟结果表明, 银纳米线的强度与孪晶界和晶粒的尺寸有关. 孪晶界密度较小(即晶粒的长径比大于1)时, 此纳米线的屈服应力比单晶纳米线还要小, 只有当孪晶界密度较大时(即晶粒的长径比小于1), 孪晶界使得纳米线得到强化. 综合分析了孪晶界和晶粒尺寸对银纳米线的影响, 为构建高强度金属纳米线打下基础. 最后讨论了温度和拉伸速度对孪晶纳米线屈服应力所产生的影响, 随着温度的升高, 孪晶纳米线与单晶纳米线的屈服应力差先升高后趋于稳定; 当拉伸速度逐渐增大, 孪晶纳米线与单晶纳米线的屈服应力差先稳定后增大.     

Synthesis of aromatic tetracyclic tin compounds by template and transmetallation reactions: Alkyl vs aryl migration from tin to nitrogen

The syntheses of [bis(3,5-di-tert-butyl-2-hydroxy-2-phenyl)amine]diphenyltin (1) and [bis(3,5-di-tert-butyl-2-hydroxy-2-phenyl)amine]dichloro-phenyl-stannate (2) by template reactions using 3,5-di-tert-butylcatechol, aqueous ammonia and SnPh₂Cl₂ are reported. We also report the syntheses of compounds 2, [bis(3,5-di-tert-butyl-2-hydroxy-2-phenyl)amine]trichloro-stannate (4), [bis(3,5-di-tert-butyl-2-hydroxy-2-phenyl)methylamine]chloro-methyltin (5), and [bis(3,5-di-tert-butyl-2-hydroxy-2-phenyl)-n-butylamine]n-butyl-chlorotin (6) and [bis(3,5-di-tert-butyl-2-hydroxy-2-phenyl)amine]n-butyl-dichloro-stannate (7), performed by transmetallation reactions of the octahedral zinc coordination compound Zn[3,5-di-tert-butyl-1,2-quinone-(3,5-di-tert-butyl-2-hydroxy-1-phenyl)imine]₂ (3) with SnPhCl₃ or SnPh₂Cl₂, SnCl₄, SnMe₂Cl₂, Sn(nBu)₂Cl₂ and Sn(nBu)Cl₃, respectively. The X-ray diffraction structures of compounds 1, 2, 4 and 6 are reported. The transmetallation reactions with Sn(alkyl)₂Cl₂ afforded pentacoordinated tin compounds, where an alkyl group migrated from tin to nitrogen, while similar reactions with Sn-Ph compounds did not present any phenyl group migration.     

Micro-thermal analysis of thermal conductance distribution in advanced silicon nitrides

A micro-thermal analysis technique was applied to investigate advanced silicon nitride materials, which exhibit high thermal conductivity. Local thermal properties in the microstructure were evaluated, and the grain boundaries were observed to have lower thermal conductance than the Si₃N₄ grains. It was found that thermal conductance both in the grains and boundaries was lowered by the addition of the sintering aid Al₂O₃, which is soluble in Si₃N₄ grains. This indicates that high thermal conductivity in silicon nitride ceramics is achieved both by grain growth, leading to a reduction in boundary density, and by eliminating soluble elements in silicon nitride grains. This revised version was published online in August 2006 with corrections to the Cover Date.     

The Effect of SiO2 Addition on the Grain Size and Photocatalytic Activity of TiO2 Thin Films

The uniform transparent TiO₂/SiO₂ nanometer composite thin films were prepared via sol-gel method on the soda lime glass substrates, and were characterized by X-ray photoelectron spectroscopy (XPS), FTIR spectroscopy, UV-VIS spectroscopy, transmission electron microscopy (TEM), X-ray diffraction (XRD) and BET surface areas. It was found that the addition of SiO₂ to TiO₂ thin films could suppress the grain growth of TiO₂ crystal and increase the hydroxyl content of the surface of TiO₂ films. The photocatalytic activity of the as-prepared TiO₂/SiO₂ composite thin films increases for SiO₂ content of less than 5 mol%.