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A new ternary complex [Ni(phen)(pmal)]·8H2O (phen = 1,10-phenanthroline,pmal2- = phenethyl malonic acid) has been synthesized by the reaction of nickel acetate, phen and phenethyl malonic acid. Elemental analysis, IR spectra and X-ray single-crystal diffraction were carried out to determine the composition and crystal structure. Crystal data for this complex: triclinic system, space group P1, a = 10.387(5), b = 13.112(6), c = 14.229(6) (A), α = 76.176(7), β =83.778(8), y = 71.770(6)°, C35H42N4O12Ni, Mr= 769.44, Z = 2, F(000) = 808, V = 1786.1 (A)3, Dc =1.431 g/cm3, μ = 0.612 mm-1, the final R = 0.0653 and wR = 0.1033 for 9379 (Rint = 0.0244)independent reflections and 4730 observed reflections (I > 2σ(I)). Structural analysis shows that the coordination geometry of Ni(Ⅱ) is a distorted octahedron. A novel two-dimensional structure is constructed from (H2O)4 and (H2O)12 water clusters, and the complex forms a 3-D network supramolecular structure by hydrogen bonds and π-π stacking of neighboring phens.  相似文献   
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建立液相色谱-串联质谱(LC-MS/MS)检测生物合成咖啡酸苯乙酯体系中咖啡酸(Caffeic acid,CA)和咖啡酸苯乙酯(Caffeic acid phenethylester,CAPE)的方法。采用LC-MS/MS电喷雾电离(ESI),负离子选择反应监测(SRM)模式检测。以V(乙腈)∶V(水)∶V(冰醋酸)=55∶45∶0.5为流动相,流速1.0mL/min,Hypersil C18色谱柱分离并检测生物合成咖啡酸苯乙酯体系中的咖啡酸以及咖啡酸苯乙酯的含量,并对生物合成咖啡酸苯乙酯的收率进行了动力学分析。本方法在进样量为0.2~20μg时具有良好的线性关系,咖啡酸和咖啡酸苯乙酯样品的加标回收率分别为93.4%~98.2%和90.3%~97.8%,相对标准偏差分别为1.79%~2.56%和1.82%~3.67%,咖啡酸苯乙酯收率在3d内可以达到15.54%,表明本方法简便、快速、可靠。  相似文献   
4.
Phenethyl isothiocyanate (PEITC) is a promising chemopreventive agent present in cruciferous vegetables. This paper describes the development of a method for the determination of PEITC in human plasma by liquid chromatography/tandem mass spectrometry (LC‐MS/MS). Atmospheric‐pressure chemical ionization was found more suitable for ionization of PEITC than electrospray ionization. Because of the lability of PEITC, a combination of low temperature and acidification was applied to minimize the degradation during the sample collection and preparation procedure. A simple protein precipitation with acetonitrile was used for the preparation of plasma samples. The analyte and 1‐phenylpropyl isothiocyanate as internal standard (IS) were subjected to chromatographic analysis on a C18 column (50 × 2.1 mm, 5 µm) using 85% methanol as mobile phase at a flow rate of 0.3 mL/min. The total analysis time for each chromatograph was 3 min and the results were linear over the studied range (5.00–250 ng/mL). The intra‐ and inter‐day precision values were acceptable as per US Food and Drug Administration guidelines. This method was successfully applied in the determination of PEITC concentrations in plasma samples from healthy chinese Volunteers. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
5.
Periodontitis is a chronic inflammatory disease of tooth support tissues leading to progressive destruction of periodontal soft tissues as well as alveolar bone, and can be treated with anti-inflammatory and bone-protective agents to prevent disease progression. Caffeic acid phenethyl ester (CAPE) is a natural polyphenolic compound with anti-inflammation, anti-oxidation and bone tissue repair efficacy. In this work, we synthesized a thermosensitive hydrogel matrix of acetylated carboxymethyl chitosan (A-CC), and firstly applied for periodontal local drug delivery. The biocompatible CAPE-loaded A-CC hydrogel (CAPE-A-CC) has the advantages of forming a drug depot in situ, sustained release and precisely improving the drug concentration in the lesion sites compared with traditional systemic administration. In addition, CAPE-A-CC could significantly inhibit the expression of inflammatory cytokines of TNF-α, IL-1β, IL-6, and IL-17 in macrophages, and increased the expression of alkaline phosphatase (ALP) in human periodontal ligament stem cells (hPDLSC) related to osteogenesis. This study develops a novel in situ thermosensitive hydrogel delivery system to improve the therapeutic potential of natural active ingredient for periodontitis therapy.  相似文献   
6.
1 INTRODUCTION Molecular structures of metallic complex and intermolecular weak interaction mode have become the focal fields of crystal engineering and supra- molecular chemistry. As we all known, intermole- cular weak interactions include hydrogen bonds[1, 2], π-π staking interaction[3, 4], metal-metal weak inte- raction[5, 6] and chelate-ring-chelate-ring weak inte- raction, et al.[7] Binary, ternary and quaternary car- boxylic acid ligands possess versatile coordination modes with me…  相似文献   
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This review critically summarises recent novel and advanced achievements in the application of monolithic materials and related porous polymer gels in micro-fluidic devices appearing within the literature over the period of the last 5 years (2005-2010). The range of monolithic materials has developed rapidly over the past decade, with a diverse and highly versatile class of materials now available, with each exhibiting distinct porosities, pore sizes, and a wide variety of surface functionalities. A major advantage of these materials is their ease of preparation in micro-fluidic channels by in situ polymerisation, leading to monolithic materials being increasingly utilised for a larger variety of purposes in micro-fluidic platforms. Applications of porous polymer monoliths, silica-based monoliths and related homogeneous porous polymer gels in the preparation of separation columns, ion-permeable membranes, preconcentrators, extractors, electrospray emitters, micro-valves, electrokinetic pumps, micro-reactors and micro-mixers in micro-fluidic devices are discussed herein. Procedures used in the preparation of monolithic materials in micro-channels, as well as some practical aspects of the micro-fluidic chip fabrication are addressed. Recent analytical/bioanalytical and catalytic applications of the final micro-fluidic devices incorporating monolithic materials are also reviewed.  相似文献   
8.
以对羟基苯甲醛为原料,经酚羟基保护、醛基还原、氯代、氰化、水解、酯化和还原反应制得关键中间体4-苄氧基苯乙醇(6);6与溴代四乙酰基葡萄糖偶联后脱保护基合成了红景天苷,总收率12.8%,其结构经1H NMR,13C NMR,IR和HR-MS确证。  相似文献   
9.
A critical review on the effect of ultrasound (US) on enzymes and their biocatalytic action is presented here. Discussion on the information users of US acquire before utilizing the different devices, and the importance they give to US frequency is constant along the review. The authors have gone into the different areas in which the US–enzyme binomial has been applied. The lack of enough information on the US–enzyme-working conditions under which each piece of research has been developed, and the necessity to provide complete information on the data and metadata to give enough light on each piece of research (and thus on the potential comparison of results from different studies) are critically exposed. With this aim, the study has been divided into the positive effect of US on enzymes to favor the production of metabolites, polymers or proteins; and the degradation, inhibition or activation of the biocatalyst under US application. Also the effect of US on enzyme production and the main fields of application of the US–enzyme binomial are discussed.  相似文献   
10.
The structural and vibrational properties of caffeic acid phenethyl ester (CAPE) were studied using infrared and Raman spectroscopy in the solid phase and multidimensional nuclear magnetic resonance (NMR) spectroscopy in solution. The theoretical structures of the compound and of its dimer in the gas phase and in DMSO solution by using density functional theory (DFT) were studied. The harmonic vibrational frequencies for the optimized geometry of CAPE and its dimeric species were calculated at the B3LYP level of theory using the 6–31G* basis set. These data allow a complete assignment of the vibration modes of the FTIR and Raman spectra in the solid state using the scaled quantum mechanical force field (SQMFF) methodology. The vibrational analysis for the dimer was performed taking into account the correlation diagram by means of the factor group analysis in accordance with the experimental structure determined by X-ray diffraction. The presence of the dimer of CAPE is supported by the IR bands at 1654, 1635, 1563, 1533, 1300, 1107, 1050, 738 cm−1 and the Raman bands at 1684, 1681, 1634, 1112, 1050, 928, 873, 850, 740, 445, 371 and 141 cm−1. The calculated 1H and 13C chemicals shifts are consistent with the corresponding experimental NMR spectra of the compound in solution. In addition, a natural bond orbital (NBO) study revealed the characteristics of the electronic delocalization of the stable structure, while the corresponding topological properties of the electronic charge density were analyzed by employing Bader's atoms in the molecules theory (AIM).  相似文献   
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