Fragment methods for IR spectrum calculations of organophosphorus compounds

For highly toxic organophosphorus compounds on the limiting lists of the International Chemical Weapons Ban Treaty, fragment methods may be used for calculating their IR vibrational spectra; this is shown for O-alkyl alkylfluorophosphonates used as examples. The geometrical parameters and the parameters of the potential and electrooptic functions are found for the major fragments of these compounds. Due to this, fast predictive computation of IR spectra of O-alkyl alkylfluorophosphonates is possible, the accuracy of calculation being sufficient for spectral identification of these compounds; a database of the calculated IR spectra may be created.     

Comparison of different sample preparation treatments for the analysis of wine phenolic compounds in human plasma by reversed phase high-performance liquid chromatography

Phenolic compounds are common constituents of wine. Due to their healthy properties the analysis in human fluids is interesting within bioavailability evaluation. They have been reported not to be stable in human plasma, particularly at room temperature. Most sample treatments have been reported for a single compound. Our aim in this paper is to study sample handling control conditions and improve phenolic stability in human plasma samples. We tested various sample treatments to determine whether they could be used for analysing a set of phenolic compounds usually present in wines.The compounds studied were six phenolic acids, five flavonoids, trans-resveratrol and tyrosol. The effect of the following factors was explored: temperature, pH, the addition of antioxidants and the addition of anticoagulants.The results suggest that the plasma samples should be kept at temperatures below −20 °C before analysis and that 1% ascorbic acid plus 10 μl/ml o-phosphoric acid should be added. Anticoagulants (heparin or EDTA) do not play a significant role in the stability of polyphenolic compounds.The recovery values of a number of sample treatments (solid phase extraction, extraction with methanol, deproteinization, inhibition of enzymatic plasma activity) were compared. The recovery values for most phenolic compounds were better if the enzymatic plasma activity was inhibited and acidified ethanol was used for deproteinization.     

Determination of organochlorine pesticides by gas chromatography with solid-phase microextraction

Summary A study of different extraction techniques for the determination of a selected group of organochlorine compounds in surface waters is presented. Comparison of liquid-liquid extraction (LLE) with solid-phase extraction (SPE) and solid-phase microextraction (SPME) with fibers of different polarity shows that SPME with a recently commercialised fiber of polydimethylsiloxane divinylbenzene allows these compounds to be determined in surface waters with good extraction efficiencies. Extraction time, effect of temperature, ionic strength and pH were optimised, allowing quantification in agricultural effluents in the range 1.0–60 ng·L⁻¹.     

逆逐级络合物络合平衡的光度研究

在配位化学中与逐级络合物的化学平衡相反的系列：Ｍ＋Ｒ＝ＭＲ＝Ｍ２Ｒ．．．．．我们称之为“逆逐级络合物”。在状态分析中常因遇到它们的出现而引起麻烦，本文基于卡隆函数与对应溶液法拟订了一个测定它们稳定常数的方法，用于Ｆｅ（ＩＩＩ）－ＣＡＳ体系，获得了满意的结果，方法对逆逐级体系有通用性。     

化合物库的组合技巧和组合合成

从化合物库的组合技巧和组合合成方法两个方面探讨了组合化学及其在药物开发中的应用。     

Reactivity of pyrrole pigments,XIX. On the structure of Cu(II) and Zn(II) chelates of dipyrrins in solution

Summary The Cu(II) and Zn(II) chelates of 1,2,3,7,9-pentamethyldipyrrin and 1,2,3,7,9-pentamethyl-8-sulfodipyrrin are studied. When metal acetates are used for the formation of the metal complexes, dipyrrinate metal acetates could be detected as precursors of thebis-dipyrrinates.

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Reaktivität von Pyrrolpigmenten, 19. Mitt. Über die Struktur von Cu(II)- und Zn(II)-Chelaten von Dipyrrinen in Lösung

Zusammenfassung Die Cu(II)- und Zn(II)-Chelate von 1,2,3,7,9-Pentamethyldipyrrin und 1,2,3,7,9-Pentadimethyl-8-sulfodipyrrin wurden untersucht. Bei Einsatz von Metalldiacetaten für die Komplexbildung wurden Dipyrrinmetallacetate als Vorläufer derbis-Dipyrrinate nachgewiesen.

     

Characterization of Lippia sidoides oil extract-b-cyclodextrin complexes using combined thermoanalytical techniques

Thermoanalytical techniques, being rapid and un-expensive have been used for the investigation of the cyclodextrin inclusion complexes for three decades. The conventional thermoanalytical techniques (TG and DTA/DSC) follow the thermal properties of the uncomplexed compounds. Consequently, the inclusion complex formation as well as the liberation of the entrapped guest cannot be followed. Monitoring the products of the thermal fragmentation of parent cyclodextrin and the included molecule(s), applying TG-MS combined technique provides evidence concerning the inclusion complex formation, and besides, gives selective signal to follow the decomposition of the cyclodextrin inclusion complexes. b-cyclodextrin inclusion complexes of Thymol and Lippia sidoides Cham essential oil extract have been prepared and investigated using conventional and combined (TG-MS) thermoanalytical techniques. The evolved gas analysis proved the inclusion complex formation between the host and guests. By the evaluation of the experimental results the elaboration of the entrapped guests from the cyclodextrin cavity could be followed. This revised version was published online in July 2006 with corrections to the Cover Date.     

Studies on Cyclodextrin Inclusion Complex by Fluorescence Anisotropy

An equation for determining the equilibrium association constant (KA) of cyclodextrin inclusion complex with fluorescence anisotropy is derived and used to determine KA of pyrene-B-cyclodextrin inclusion complex. The existing forms of cyclodextrin inclusion complex in solution, the interaction type of host with guest, and the possibility of application of B-cyclodextrin in the analysis of metal ions using naphthalene derivative as a ligand are discussed based on the equation derived along with the curve of fluorescence anisotropy versus cyclodextrin concentration of guest/cyclodextrin system.     

混合配体、希土三元配合物的研究 Ⅳ.3,5二硝基水扬酸(H2DNSA)、邻菲咯啉(phen)、希土(RE)三元固体配合物的合成及性质

本文报道了十种希土元素与3,5-二硝基水扬酸、邻菲咯啉三元配合物的制备方法。通过元素和化学分析测定了化合物的化学组成,并用红外光谱、紫外光谱、差热分析、磁化率、X射线粉天衍射等对所合成的化合物进行了结构和性质的研究。