Co-crystallization of Resorcin[4]arene Tetracarboxylic Acid with Triethylamine: Synthesis and Crystal Structure

Treatment of resorcin[4]arene tetracarboxylic acid 1 with triethylamine in the presence of Co(CH3COO)2·4H2O and 4,4'-bipyridine gave a co-crystallization 14-·4Et3NH+(C32H20O164-·4Et3NH+,Mr=1069.27) from ethanol and water.The compound was structurally determined by single-crystal X-ray diffraction.The crystal belongs to monoclinic,space group P21/n,with a=8.1763(18),b=12.913(3),c=28.724(7) ,β=97.574(4)o,V=3006.3(12) 3,Z=2,Dc=1.181 g/cm3,F(000)=1152,Rint=0.0275,T=293(2) K,μ=0.086 mm-1,the final R=0.0634 and wR=0.1752 for 5082 observed reflections with Ⅰ 2σ(Ⅰ).The co-crystallization is very stable at room temperature.Possibly,a network of N-H···O(=C) plays an important role in the structure.Meanwhile,the compound emits a weak cyan luminescence with peak maximum band at 458 nm.     

增强化学发光酶免疫法对猪肉中盐酸克伦特罗的检测

建立了猪肉中克伦特罗(CLB)的直接竞争化学发光酶免疫检测(dc-CLEIA)方法。通过优化离子强度、pH值确立了化学发光酶免疫法的标准曲线,优化后dc-CLEIA的检出限可达0.02μg/L。猪肉中的盐酸克伦特罗用高氯酸提取、SPE净化后绘制基质曲线,基质曲线与标准曲线吻合,说明基质影响基本消除。测定0.10、1.0、5.0μg/kg 3个水平的添加回收率,平均回收率为83%~98%,批内与批间的相对标准偏差均小于15%。进一步研究了dc-CLEIA与HPLC两种方法测定猪肉样品的相关性,结果显示两者测定结果相关性良好,r=0.964 7,说明所建立的直接化学发光酶免疫方法可用于实际样品的检测,结果准确可靠。     

Direct Electrochemistry of Cytochrome c on EDTA-ZrO2 Organic-inorganic Hybrid Film Modified ElectrodesState Key Laborator3.＂ of Chemo／Biosensing and Chemometrics, Hunan Universit3; Changsha. Hunan 410082. China

A composite film of ethylenediamine tetraacetic acid (EDTA)‐ZrO₂ organic‐inorganic hybrid was prepared based on the chelation between Zr(IV) and EDTA. The direct electrochemical behavior of cytochrome c (cyt. c) at the hybrid film modified glassy carbon electrodes was investigated. The immobilized EDTA can promote the redox of heme in horse heart cyt. c which gives rise to a pair of reversible redox peaks with a formal potential of 40 mV (vs. SCE). The peak current increased linearly with the increase of cyt. c concentration in the range of 1.6 × 10^?6—8.0 × 10^?5 mol·L^?1 with the correlation coefficient of 0.996. Further investigation shows that metal ions can impede the electron transfer of cyt. c. The impediment capability of metal ions depends on their coordination capability with EDTA and their valence number.     

N-乙基-1,10-菲罗啉-2-甲胺镍(Ⅱ)配合物的合成、晶体结构及性质研究

0IntroductionPhenanthrolinederivativescontainingaminegroupshavebothsoftandhardsitesandaregooddonorsformetalions.1,10鄄phenanthrolineanditsderivativeshavebeenextensivelyusedasligandsinbothanalyticalandpreparativecoordinationchemis鄄try[1].Mostoftheseworksh…     

Effects of Divalent Metal Ions on the Chaperone Activity and Structure of Rat Lens H18G Mutant αB‐Crystallin

αB‐crystalin, a small heat shock protein and a component of α‐crystalin, is a molecular chaperone playing an important role in preventing the formation of cataracts. It has been reported that His18 is an important site for Cu²⁺ to bind with to form a stable metal complex and thus to enhance this chaperone‐like activity of human αB‐crystalin. In this work, we used site‐directed mutagenesis to clone and express H18G rat lens αB‐crystalin in order to investigate the role of His18 in chaperoning activity. We found that 1 mM of Cu²⁺, or Zn²⁺, rather than Mg²⁺, significantly enhanced the chaperone‐like activity of wild type αB‐crystalin. Whereas, it is Zn²⁺ and Mg²⁺, not Cu²⁺, that significantly reduced this activity of H18G αB‐crystalin. In the absence of cation, H18G showed better activity compared to the wild type αB‐crystalin. ANS fluorescence measurement showed there was no linear relationship between chaperone‐like activity and surface hydrophobicity, indicating that surface hydrophobicity is not a prerequisite for chaperone‐like activity. An HPLC size‐exclusion chromatography study showed that in the presence of metal ions, wild type αB‐crystalin tended to aggregate via dissociation and re‐association into a high molecular aggregate with a molecular weight higher than 1400 kDa and then precipitated, suggesting that the presence of metal ions is a factor leading to the formation of cataracts. Both the near and far UV‐CD spectra suggested that the wild type αB‐crystalin reflected more β‐sheet structural characteristics; whereas the H18G reflected more random coil characteristics. The H18G induced structural alterations as to develop more random coil characteristics and more micro‐environmental changes around the tryptophan residues. This work suggested that His18 may not be a crucial binding site for Cu²⁺, but rather that it may be an important binding site for Zn²⁺ in terms of chaperone‐like activity and the process of metal induced self‐aggregation is prerequisite for chaperone‐like activity to occur.     

N‐glycosylation approach to glucose‐functionalized diamine and its use for protection‐free synthesis of polyurea bearing glucoside pendant

A glucose‐functionalized diamine was prepared and used as a new monomer for polyurea synthesis. The diamine was prepared by N‐glycosylation of 1,6‐hexamethylenediamine with D ‐glucose. Upon adding diisocyanates to the diamine, isocyanate reacted selectively with the amino groups, not with the hydroxyl groups of the glucose‐derived structure, to give the corresponding polyureas. The polyureas exhibited highly hydrophilic nature due to the presence of the glucose‐derived side chain. A ternary system consisting of the glucose‐functionalized diamine, piperazine, and diisocyanate gave the corresponding polyureas, where content of the glucose‐derived moiety was tunable by feed ratio between the diamine and piperazine. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013     

Clean,One‐Pot Synthesis of Naphthopyran Derivatives in Aqueous Media

A general and practical one‐pot synthesis of naphthopyran derivatives using hexadecyltrimethylammonium bromide (HTMAB) as catalyst (10 mol%) is described. This method provides several advantages such as neutral conditions, high yields and simple workup procedure. The catalyst is low cost, facile, active, environmentally friendly, and reusable. In addition, water is chosen as a green solvent.     

C NMR spectra of cyclomercurated ferrocenylimines: Substituent effects and conformations in the ferrocenes

Three series of cyclomercurated ferrocenylimines (2-chloromercurio-ferrocenylimines) have been studied using ¹³C NMR spectroscopy. Good to excellent linear relationships have been found to exist between the chemical shifts of the carbon atoms in the ferrocenyl moiety and normal Hammett substituent constants σ_m and σ_p. The δ values of the iminyl carbon atoms show excellent linear correlations with the σ values. In three series of the ferrocenes, the sensitivity of the carbon atoms to the substituent effect is different, which is discussed in terms of the twist angle between the N-phenyl ring and the C---C=N---C plane. The relative sensitivity of the chemical shifts on different positions in ferrocenyl moiety to the substituent effect has also been presented.     

利用正相高效液相色谱制备新地质卟啉化合物

以Ａｅｔｉｏ和ＯＥＰ型卟啉为标样,探讨了正相高效液相色谱体系流动相的稳定性,发现溶剂系统的完全脱水,脱气是影响流动相的主要因素,最终采用的条件具有的稳定性,重现性,在所建立的色谱体系中,对江汉油样地质卟啉中所含新化合物利用半制备柱,分析柱进行单体分离,得到高纯度（９５．４％）的单体新卟啉化合物。     

稀土奥贝蠕铁制取工艺及其性能的研究

稀土奥贝蠕铁可用含稀土的蠕化剂及等温淬火工艺稳定地制取,藉助高温扫描电子显微镜,观察并研究了稀土蠕铁奥氏体化过程及稀土奥贝蠕铁随温度升高时组织的变化。用带有加热装置的万能材料试验等土奥贝蠕铁的各种性能进行了系统测定了如抗拉强度、延伸率、冲吉韧性、热膨胀系数及伸长百分率,结果表明,稀土奥贝蠕铁在室温和高温下均有良好的性能。