Heck Reaction Catalyzed by Palladacycle in Neat Water

Cydopalladated ferrocenylimine has been found to be a type of excellent phosphine-free catalyst for Heck reactions in neat water with both higher yields and turnover numbers than those reported in the literature up to now. Some commercial emulsifying agents, indodin~ the commonly used quaternary ammonium salts, have been proved to be excellent additives in the catalysis of the reactions. Not only aromatic iodide, but also aromatic bromide could be coupled with the olef‘ms. All rcactions were able to be conducted in air under refluxlng condition.     

3-芳基戊二酰基双(4′-苯并-15-冠-5)的合成

苯甲醛和对氯苯甲醛在碱存在下分别与4′-乙酰基苯并-15-冠-5缩合,生成冠醚化查尔酮1a和1b。此二化合物作为中间体进一步与4′-乙酰基苯并-15-冠-5发生Michael反应,生成两种酮型双冠醚2a和2b。     

Preparation of Novel Side-chain Pseudopolyrotaxanes Consisting of Cucurbituril[6] and Polyamine Salts

Pseudorotaxane monomer （VBCB） containing cucurbitutil[6] （CB[6]） and N^1-（4-vinylbenzyl）-1,4-diaminobutane dihydrochloride （VBDADC） is obtained by self-assembly of cucurbituril[6] with VBDADC in water and then polymerized using potassium persulfate （KPS） as initiator to give novel water-soluble side-chain cucurbituril[6]-based pseudopolyrotaxane（PVBCB）. The chemical structures of PVBCB, VBCB and VBDADC are confirmed by ^1H NMR,^13C NMR spectra and elemental analysis. In VBCB, CB[6] is localized aliphatic group of the side chain and the molar ratio of CB[6] to VBDAC is 1：1 .     

聚芴类发光材料合成中间体的质谱分析

利用电喷雾电离（ESI）质谱－质谱（MS－MS）技术，分析了新化合物2，7－双（4，4，5，5－四甲基－1，3，2－二氧杂硼烷－2－基）－9，9－二辛基芴的EI和ESI的质谱，确认了该谱图中母离子和子离子的关系，讨论了其碎裂途径，为其结构鉴定提供了依据。     

微型CCD光谱仪在光谱分析中的应用

现代分析仪器的一个重要发展趋势是仪器的小型化（miniaturization）、微型化（microminiaturiza．ion），甚至于芯片实验室（lab-on-a-chip；或称微全分析系统，micro total analysis system，μ-TAS）。因此，许多科学工作者在提高光谱分析仪器的基本部件——辐射源、样品室、分光元件和检测器的性能和减小其体积方面做了大量的研究工作。半导体检测器在光谱分析中的应用越来越广泛，在实验室和实际工作中常常会接触到摄谱仪、光电倍增管（photomultiplier tube，PMT）和电荷耦合器件（charge coupled device，CCD）等，本文介绍微型CCD光谱仪在本科教学中的一些应用。     

MOLECULAR CLONING OF A NEW VARIANT OF HUMAN PAPILLOMAVIRUS TYPE 6 ISOLATED FROM A CHINESE WOMAN AND EXPRESSION OF ITS L1 GENE IN E. coli——MOLECULAR CLONING & EXPRESSION OF HPV6 GENE

A human papillomavirus genome DNA of 7.9 kb from a Chinese woman with genital condyloma acuminata was cloned in Bam HI site of pAT153. According to the results obtained from Southern blotting, restriction mapping as well as partial DNA sequencing, the isolated genome (HPV6BV) had obvious variance and was referred to as a new variant of HPV6 found in China the first time. HPV6BV L1 gene was successfully expressed in E. coli as a fusion protein with pUR288. The β-galactosidase/L1 fusion protein reacted with both β-galactosidase antiserum and HPV antibody using Western blot technique. The E. coli-produced fusion protein, possessing HPV antigenicity, may provide a reagent for clinical diagnosis and epidemiological survey.     

溶剂热合成具有海绵状结构的介孔SnO2

采用溶剂热方法, 以SnCl4·5H2O/尿素/乙醇三元体系合成了具有特定结构的前驱体, 该前驱体经焙烧后得到了具有海绵状结构的介孔SnO2. 利用X射线粉末衍射(XRD)、傅立叶红外吸收光谱(FT-IR)、透射电镜(TEM)、热分析(TG-DTA)和氮气等温吸附鄄脱附等方法对产物的结构、形貌和热稳定性进行表征. 结果表明, 300 ℃焙烧处理后的样品由粒径约为5 nm的纳米粒子堆积而形成海绵状结构, 其中孔的尺寸范围在2-8 nm, 样品比表面积达到了134 m2·g-1.     

热喷雾进样镍管火焰炉原子吸收法直接测定葡萄酒中的镉

报道了用热喷雾进样镍管火焰炉原子吸收光谱法直接测定葡萄酒中的镉。热喷雾毛细管和火焰炉内的高温及氧化性气氛可以使样品实现在线消解和镉的测定。将葡萄酒样品浓缩后加入2%HNO3和10%H2O2,直接进样测定。其测定结果与ICP-MS法吻合较好,葡萄酒样品加标回收率在93%~107%之间。该法简单、快速,灵敏度高。     

Crystal Structure of Sar1[H79G]-GDP Which Provides Insight into the Coat-controlled GTP Hydrolysis in the Disassembly of COP Ⅱ

Sar1 is a small GTPase involved in COPⅡ vesicle transport. Previous studies showed that H79G mutation of Sar1 can lock Sar1 in its GTP-bound active conformation, stabilize coat assembly, and prevent the disassembly of COP Ⅱ vesicle coats by reducing Sec23/24 GAPstimulated hydrolysis. We show here that the replacement of His79 by glycine induces a large conformation change in switch Ⅱ and results in the lost of hydrogen bond between His79 and its associated nucleophilic water molecule that was hypothesized to reduce the GAP-stimulated hydrolysis during the COP Ⅱ assembly and disassembly. These results confirm that the switch Ⅱ conformation is important for COP Ⅱ disassembly through coat-controlled GTP hydrolysis.     

胰蛋白酶和苯酰氨类抑制剂结合自由能的预测

用基于线性响应近似的自由能预测方法计算胰蛋白酶和苯酰氨类抑制剂的结合 自由能。计算结果表明,单参数,双参数和三参数模型具有相似的线性回归系数, 但三参数和双参数模型的交互验证回归系数要明显优于单参数模型。从预测能力来 看,双参数模型和三参数模型都能够很好地预测测试集中抑制剂的结合自由能,其 中双参数模型预测的结果要略优于三参数模型的预测结果。对测试集中的抑制剂, 双参数模型预测得到的预测自由能和实际自由能之间平均绝对误差仅为1.15 kJ/mol。自由能计算模型以及分子动力学轨迹能很好地解释抑制剂结构和活性的 关系,为药物设计提供了重要的结构信息。