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JPC – Journal of Planar Chromatography – Modern TLC - A ternary mobile phase for thin-layer chromatographic separation and identification of seven amino acids on microcrystalline... 相似文献
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JPC – Journal of Planar Chromatography – Modern TLC - Optimization of the separation and identification of heavy metals present in cotton material has been performed by... 相似文献
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Ljerka Tuek-Boi Christophe Pannecouque Erik De Clercq Jan Balzarini 《Polyhedron》2009,28(16):3449-3458
The eco-friendly synthesis, spectroscopic (IR, MS, 1H and 13C NMR) study and biological (cytostatic, antiviral) activity of sodium and potassium benzeneazophosphonate complexes, obtained by reaction in the solid state under microwave irradiation of the alkali salts of ethyl [α-(4-benzeneazoanilino)-N-benzyl]phosphonic acid and [α-(4-benzeneazoanilino)-N-4-methoxybenzyl]phosphonic acid with crown ethers containing 18-membered (dibenzo-18-crown-6 and bis(4′-di-tert-butylbenzo)-18-crown-6), 24-membered (dibenzo-24-crown-8) and 30-membered (dibenzo-30-crown-10) macrocyclic rings, have been described. The simple work-up solvent free reaction is an efficient green procedure for the formation of mononuclear crown ether complexes in which the sodium/potassium ion is bound to oxygen atoms of the macrocycle and the phosphonic acid oxygen. The free crown ethers, alkali benzeneazophosphonate salts and their complexes were evaluated for their cytostatic activity in vitro against murine leukemia L1210, murine mammary carcinoma FM3A and human T-lymphocyte CEM and MT-4 cell lines, as well as for their antiviral activity against a wide variety of DNA and RNA viruses. The investigated compounds showed no specific antiviral activity, whereas all the free crown ethers and their complexes demonstrated cytostatic activity, which was especially pronounced in the case of bis(4′-di-tert-butylbenzo)-18-crown-6 and its complexes. 相似文献
4.
Influence of phenylenediamine additions on the morphology and on the catalytic effect of polyaniline
Ljerka Dui Marijana Kralji Sanja Grigi 《Journal of polymer science. Part A, Polymer chemistry》2004,42(7):1599-1608
The influence of para‐, ortho‐, and meta‐phenylenediamine (p‐, o‐, and m‐PDA) additions on the electrochemical synthesis of polyaniline has been investigated by the use of cyclic voltametry. It has been found that small additions (1 and 5 mmol L?1) of PDA monomers influence significantly the polymerization rate. Whereas p‐PDA increases the polymerization rate, the addition of o‐ or m‐PDA slows it down. Therefore, a different number of potential cycling is necessary to obtain similar thickness of layers. The layers exhibit very different morphology, which changes from “spaghetti‐like” for polyaniline to “sponge‐like” for p‐PDA, to “pebble‐like” for o‐PDA and to “cauliflower‐like” for m‐PDA additions, respectively. The catalytic effect of the synthesized polymer layers has been tested. It has been found that all the layers exhibit catalytic effect in lowering the redox potential of hydroquinone/quinone tested reaction, but the rate of the electrocatalytic reaction varies depending on the PDA monomer added. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 1599–1608, 2004 相似文献
5.
Ljerka Lovri 《Journal of Polymer Science.Polymer Physics》1969,7(8):1357-1366
Three types of commercial styrene–acrylonitrile copolymer were fractionated by coacervate extraction and by column-elution techniques. Both methods were studied with two different solvent–nonsolvent pairs. Glass wool was used as the support material in the column. Fractionation by the coacervate extraction method was studied with benzene–triethylene glycol as a solvent–nonsolvent system at 60°C and with dichloromethane–triethylene glycol at 25°C. Column elution was carried out with acetone–methanol as the solvent–nonsolvent system at 30°C, and with dichloromethane–methanol at 20°C. Results of excellent reproducibility were obtained by these two methods. Characterization of fractions involved determination of both the molecular weight and chemical composition. It was established that the fractionation of the samples tested was dependent upon molecular weight only. The two methods described above are compared. Each gives an efficient procedure for fractionation of styrene–acrylonitrile copolymers. 相似文献
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7.
The complex-forming properties of monoethyl 8-quinolylmethylphosphonate (8-Hmqmp) towards palladium(II) ion have been investigated by reactions of the hydrochloride, 8-Hmqmp · HCl · H2O, and sodium salt, Na(8-mqmp) · 2H2O, of this monoester with palladium(II) halide compounds in aqueous solution over a wide pH range. Depending on pH and initial quinolinium and palladium salts, four types of complexes have been formed. Under acidic solution the ion-pair salt complexes [8-H2mqmp]2[PdX4] (1 and 2, pH < 3) and [8-H2mqmp]2[Pd2X6] (3 and 4, pH ∼ 3), with protonated quinoline ligand as cation and tetrahalopalladate or hexahalodipalladate complex as anion (X = Cl, Br), were isolated. By heating in methanol the chloro complexes 1 and 3 as well as bromo complexes 2 and 4 were converted into the quinolinium salt complexes, [8-H2mqmp][Pd(8-Hmqmp)X3], 5 and 6, respectively, containing as anion the quinoliniummethylphosphonatetrihalopalladate complex with palladium bonded at the phosphonic acid moiety. The chelate complex 7, [Pd(8-mqmp)2], with ligand bonded through the quinoline nitrogen and the deprotonated phosphonic acid oxygen and forming two seven-membered {N,O} chelate rings, was obtained in neutral and basic media. The complexes were identified and characterized by elemental analysis, magnetic and conductance measurements, spectroscopic studies (IR, 1H NMR, UV–Vis, positive/negative ion FAB MS) and thermal analysis (TG, DTA). As a preliminary screening for their biological activity, complexes were investigated for their ability to inhibit the cancer growth in vitro in the human KB and murine L1210 cell lines. The results obtained were compared with those obtained for the complexes of diethyl 8-quinolylmethylphosphonate (8-dqmp) and monoethyl 2-quinolylmethylphosphonate (2-Hmqmp), and structural factors that determine the complex activity were discussed. 相似文献
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Aleksandar Vinjevac Ljerka Tuek‐Boi 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(6):o434-o437
The crystal structures of the potential antitumour agents monoethyl (α‐anilinobenzyl)phosphonate, C15H18NO3P, (I), and its 4‐azobenzene‐substituted derivative monoethyl {α‐[4‐(phenyldiazenyl)anilino]benzyl}phosphonate, C21H22N3O3P, (II), are described. A zwitterionic form of (I) and a neutral molecular form of (II) are observed, which is fully in accordance with previously reported spectroscopic studies. In both structures, hydrogen bonding induces the formation of zigzag head‐to‐head double layers parallel to the crystallographic b axis. 相似文献
9.
Ivanka Matijašić Paolo Dapporto Patrizia Rossi Ljerka Tušek-Božić 《Supramolecular chemistry》2013,25(1):193-206
Abstract Crown ether complexes formed by the dibenzo–30-crown–10 (DB30C10) with potassium and ammonium hexafluorophosphate have been prepared and their crystal structures have been determined by single crystal X-ray analyses. The potassium complex (compound 1) consists of [K(DB30C10)]+ cation and PF6 ? anion. Crystals are monoclinic, space group P2/n, with a = 11.9106(3), b = 9.8382(5), c = 14.3062(3) Å, β = 97.581(3)°, V = 1661.7(1) Å3, Dc = 1.440 g cm?3, Z = 4, R = 0.0675 for 2528 unique observed reflections. The potassium atom is coordinated to the ten oxygen atoms of the crown ligand at the distance from 2.859(3) to 2.930(3) Å. The ammonium complex (compound 2) has also 1:1 crown—cation ratio. Crystals are monoclinic, space group P21/n, with a = 12.5061(6), b = 19.3724(5), c = 14.2203(9) Å, β = 102.476(5)°, V = 3363.8(3) Å3, Dc = 1.501 g cm?3, Z = 4, R = 0.0677 for 4172 unique observed reflections. The ammonium cation is completely enclosed with crown oxygen atoms forming seven hydrogen bonds. The conformation of previously reported dibenzo-30-crown-10 complexes with potassium salts were investigated using polar coordinate maps. 相似文献
10.
Juribašić M Bellotto L Traldi P Tušek-Božić L 《Journal of the American Society for Mass Spectrometry》2011,22(10):1815-1825
The mass spectrometric behavior of palladium(II) halide complexes of three types of quinolinylaminophosphonates, diethyl and
dibutyl esters of [α-anilino-(quinolin-2-yl)methyl]phosphonic (L1, L2), [α-anilino-(quinolin-3-yl)methyl]phosphonic (L3, L4), and [α-(quinolin-3-ylamino)-N-benzyl]phosphonic acid (L5, L6), was investigated under positive ion electrospray ionization conditions. Each type of ligand forms complexes with different
metal–ligand interactions. Mononuclear dihalide adducts cis-[Pd(L1/L2)X2] (1–4) and trans-[Pd(L3/L4)2X2] (5–8) as well as dinuclear tetrahalide complexes [Pd2(L5/L6)3X4] (9–12) (X = Cl, Br) are formed by metal bonding either through the quinoline or both the quinoline and amino nitrogen atoms. The
sodiated molecule [M + Na]+ is observed in the mass spectra of all the complexes, and its abundance as well as the fragmentation pathway depend on the
type of the complex. In the cis complexes (1–4) the initial decomposition goes under two fragmentation routes: those in which the sodium molecular adduct sequentially loses
halides HX/NaX and those in which this loss is in the competition with the loss of dialkyl phosphite. The predominant pathways
for decomposition of trans dihalide (5–8) and tetrahalide (9–12) complexes include three competitive reactions; the loss of halides, dialkyl phosphites and the intact phosphonate ligand
molecule and its fragments formed by ester dissociation or complete loss of the phosphonate ester moiety. A series of acetonitrile
adducts and cluster ions derived from dimolecular clusters [2M + Na]+ were also detected. The most important fragmentation patterns are rationalized and supported by the MS
n
studies. 相似文献