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  • Publication
    Accès libre
    Encapsulation of Photosensitizers in Hexa- and Octanuclear Organometallic Cages: Synthesis and Characterization of Carceplex and Host-Guest Systems in Solution
    Cationic arene ruthenium assemblies of the general formulas [Ru6(p-cymene)6(tris-pvb)2(?2-Cl)6]6+, [Ru6(p-cymene)6(tris-pvb)2(OO?OO)3]6+ (tris-pvb = 1,3,5-tris{2-(pyridin-4-yl)vinyl}benzene), and [Ru8(p-cymene)8(NN?NN)2(OO?OO)4]8+ (NN?NN = 1,2,4,5-tetrakis{2-(pyridin-4-yl)vinyl}benzene, 1,2,4,5-tetrakis{2-(pyridin-4-yl)ethynyl}benzene) have been obtained from the corresponding dinuclear arene ruthenium complexes [Ru2(p-cymene)2(?-Cl)2Cl2] and [Ru2(p-cymene)2(OO?OO)Cl2] (OO?OO = oxalato, 2,5-dioxido-1,4-benzoquinonato, 2,5-dichloro-1,4-benzoquinonato, 5,8-dioxido-1,4-naphthoquinonato, 5,8-dioxido-1,4-anthraquinonato, 6,11-dioxido-5,12-naphthacenedionato) by reaction with the multidentate ligands and silver trifluoromethanesulfonate. These cationic hexa- and octanuclear cages have been isolated and characterized as their triflate salts. Addn. of coronene during the synthesis of the large hexanuclear assemblies leads to the direct encapsulation of coronene in the cavity of the trigonal-prismatic complexes. Photosensitizers such as porphin, phthalocyanine, and Zn-phthalocyanine present during the synthesis of these metalla-cages are encapsulated in five of these arene ruthenium complexes to give photosensitizer-encapsulated systems. The host-guest properties of these systems were studied in soln. by DOSY, 2D NOESY and 2D ROESY NMR spectroscopy. The H···H distances between guests and selected metalla-cages were estd. by 2D ROESY NMR spectroscopy and modelization. NMR analyzes indicate that the guest photosensitizers are completely encapsulated in two of these metalla-cages, while in the three other ruthenium cages NMR spectra reveal an equil. between empty and filled cages. [on SciFinder(R)]
  • Publication
    Accès libre
    Thiolato-Bridged Arene–Ruthenium Complexes: Synthesis, Molecular Structure, Reactivity, and Anticancer Activity of the Dinuclear Complexes [(arene)2Ru2 (SR)2Cl2]
    (2012)
    Ibao, Anne-Flore
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    Gras, Michaël
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    ; ;
    Zava, Olivier
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    Dyson, Paul J.
    Treatment of an arene–ruthenium dichloride dimer with thiols RSH to lead to cationic trithiolato complexes of the type [(arene) 2Ru2(SR)3]+ was shown to proceed through the neutral thiolato complexes [(arene)2Ru2(SR)2Cl2], which have been isolated and characterized for arene = p-MeC6H4iPr and R = CH2Ph (1), CH2CH2Ph (2), CH2C6H4-p-tBu (3), and C6H11 (4). The single-crystal X-ray structure analysis of the p-tert-butylbenzyl derivative 3 reveals that the two ruthenium atoms are bridged by the two thiolato ligands without a metal–metal bond. The neutral dithiolato complexes[(arene)2Ru2(SR)2Cl2] (1–3) are intermediates in the formation of the cationic trithiolato complexes [(arene)2Ru2(SR)3]+ (5–7). Of the new [(arene)2Ru2(SR)2Cl2] complexes, derivative 2 is highly cytotoxic against human ovarian cancer cells, with IC50 values of 0.20 μM for the A2780 cell line and 0.31 for the cisplatin-resistant cell line A2780cisR.
  • Publication
    Accès libre
    Organometallic Cages as Vehicles for Intracellular Release of Photosensitizers
    (2012)
    Schmitt, Frédéric
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    Barry, Nicolas P.E.
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    Juillerat-Jeanneret, Lucienne
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    Water-soluble metalla-cages were used to deliver hydrophobic porphin molecules to cancer cells. After internalization, the photosensitizer was photoactivated, significantly increasing the cytotoxicity in cells. During the transport, the photosensitizer remains nonreactive to light, offering a new strategy to tackle overall photosensitization, a limitation often encountered in photodynamic therapy.
  • Publication
    Accès libre
    Template-Directed Synthesis of Hexanuclear Arene Ruthenium Complexes with Trigonal-Prismatic Architecture Based on 2,4,6-Tris(3-pyridyl)triazine Ligands
    Cationic arene ruthenium metalla-prisms of the general formula [Ru6(p-cymene)6(3-tpt)2(OOOO)3]6+ (3-tpt = 2,4,6-tris(3-pyridyl)-1,3,5-triazine; OO∩OO = 5,8-dioxido-1,4-naphthoquinonato [1]6+ or 6,11-dioxido-5,12-naphthacenedionato [2]6+) have been obtained from the corresponding dinuclear arene ruthenium complexes [Ru2(p-cymene)2(OOOO)Cl2] by reaction with 3-tpt, silver trifluoromethanesulfonate in the presence of an aromatic molecule (1,3,5-tribromobenzene, phenanthrene, pyrene, or triphenylene) that acts as a template. While the large template molecule triphenylene is permanently encapsulated in the metalla-prisms to give the complexes [triphenylene⊂1]6+ and [triphenylene⊂2]6+, 1,3,5-tribromobenzene can be removed in toluene, thus leaving the empty cages [1]6+ and [2]6+, which are isolated as their trifluoromethanesulfonate salts. In the case of the metalla-prism connected by the 5,8-dioxido-1,4-naphthoquinonato bridging ligands, the NMR spectrum reveals two isomers, 1a and 1b, the formation of which can be rationalized by means of multiple NMR experiments (one-dimensional, two-dimensional, ROESY, and DOSY). The empty and filled metalla-prisms, [1]6+, [2]6+, [template⊂1]6+, and [template⊂2]6+, have been characterized by NMR, UV−vis, and IR spectroscopy. The slow exchange processes of a guest molecule moving in and out of the cavity of cages [1]6+ and [2]6+ have been studied in solution with phenanthrene and pyrene. One-dimensional exchange spectroscopic (1D EXSY) measurements show that [phenanthrene⊂1]6+ is in a faster exchange regime than [phenanthrene⊂2]6+ and that phenanthrene is more easily exchanged than pyrene in cages [1]6+ and [2]6+, all observations being consistent with the portal size of the cages.
  • Publication
    Accès libre
    Dichlorido(furfurylamine-κN)(η6-hexamethylbenzene)ruthenium(II)
    The single-crystal X-ray structure analysis of [RuCl2(C12H18)(C5H7NO)] reveals a distorted piano-stool geometry around the RuII atom, with a hexamethylbenzene ligand, two chloride ligands and a furfurylamine ligand, the latter coordinating through the amine group. In the crystal, a dimeric structure is observed as a result of N-H...Cl interactions between two symmetry-related molecules.
  • Publication
    Accès libre
    Dichlorido[1-(2-chloroethyl)-3-(pyridin-4-ylmethyl-κN)urea](η6-hexamethylbenzene)ruthenium(II) chloroform monosolvate
    (2011)
    Auzias, Mathieu
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    The RuII atom in the title compound, [RuCl2(C12H18)(C9H12ClN3O)]•CHCl3, exhibits a typical piano-stool coordination, defined by a hexamethylbenzene ligand, two chloride ligands and a pyridylurea ligand coordinated through the pyridine N atom. In the crystal, a dimeric structure is observed due to two strong N-H...Cl interactions between the NH groups of urea and the two chloride ligands of neighbouring molecules. In addition, the C=O group of the urea moiety interacts with the solvent molecule through weak C-H...O interactions.
  • Publication
    Accès libre
    Arene ruthenium bis-saccharinato complexes: Synthesis, molecular structure and catalytic oxidation properties in aqueous solution
    (Elsevier, 2011)
    Thai, Trieu-Tien
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    Arene ruthenium complexes [(η6-arene)Ru(sacc)2(OH2)] (arene = para-cymeme, benzene) containing an aqua and two saccharinato ligands have been synthesized from [(η6-arene)RuCl2]2 and sodium saccharinate in a water-ethanol mixture (1:1). The aqua complex [(η6-MeC6H4Pri)Ru(sacc)2(OH2)] reacts with acetonitrile to give the acetonitrile complex [(η6-MeC6H4Pri)Ru(sacc)2(NCMe)]. The corresponding benzene derivative [(η6-C6H6)Ru(sacc)2(NCMe)] was obtained from [(η6-C6H6)RuCl2]2 and saccNa in an acetonitrile-methanol mixture (1:1). All new complexes show a piano-stool geometry with two mono-hapto nitrogen-bonded saccharinato ligands in addition to a H2O or MeCN ligand. All complexes of the type [(η6-arene)Ru(sacc)2(OH2)] and [(η6-arene)Ru(sacc)2(NCMe)] were found to catalyze the oxidation of secondary alcohols with tert-butyl hydroperoxide (ButOOH) to give the corresponding ketones in aqueous solution.
  • Publication
    Accès libre
    Ru2(CO)4(OOCR)2L2 sawhorse-type complexes containing axial 5-(4-pyridyl)-10,15,20-triphenylporphyrin ligands
    (2011)
    Gras, Michaël
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    Barry, Nicolas P.E.
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    The thermal reaction of Ru3(CO)12 with various carboxylic acids (benzoic, 4-hydroxyphenylacetic, ferrocenic, stearic, oleic, 4-(octadecyloxy)benzoic) in refluxing tetrahydrofuran, followed by addition of 5-(4-pyridyl)-10,15,20-triphenylporphyrin (L), gives the dinuclear complexes Ru2(CO)4(OOCR)2L2 (1: R = –C6H5, 2: R = –CH2-p-C6H4OH, 3: R = –C5H4FeC5H5, 4: R = –(CH2)16CH3, 5: R = –(CH2)7CHdouble bond; length as m-dashCH(CH2)7CH3, 6: R = –p-C6H4O(CH2)17CH3). Complexes 1–6 were characterised by IR, NMR, and ESI-MS as well as by elemental analysis. The UV–Vis spectra show the Soret band centred at 417 nm and the Q bands at 515, 550, 590 and 645 nm, respectively.
  • Publication
    Accès libre
    [6-(Hydroxymethyl)pyridin-2-yl]methyl ferrocene-1-carboxylate
    (2011)
    Auzias, Mathieu
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    The crystal structure of the title ferrocene derivative, [Fe(C5H5)(C13H12NO3)], shows strong intermolecular O-H...N hydrogen bonds between the alcohol function and the pyridine group of a neighbouring molecule, while the pyridine function forms another hydrogen bond with the alcohol function of another neighbouring molecule, resulting in the formation of chains along the a-axis direction.
  • Publication
    Accès libre
    Thiophenolato-bridged dinuclear arene ruthenium complexes: a new family of highly cytotoxic anticancer agents
    (2010)
    Gras, Michaël
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    ; ;
    Zava, Olivier
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    Dyson, Paul J.
    New cationic diruthenium complexes of the type [(arene)2Ru2(SPh)3]+ , arene being C6H6, p-iPrC6H4Me, C6Me6, C6H5R, where R = (CH2)nOC(O)C6H4-p-O(CH2)6CH3 or (CH2)nOC(O)CH[double bond, length as m-dash]CHC6H4-p-OCH3 and n = 2 or 4, are obtained from the reaction of the corresponding precursor [(arene)RuCl2]2 and thiophenol and isolated as their chloride salts. The complexes have been fully characterised by spectroscopic methods and the solid state structure of [(C6H6)2Ru2(SPh)3]+, crystallised as the hexafluorophosphate salt, has been established by single crystal X-ray diffraction. The complexes are highly cytotoxic against human ovarian cancer cells (cell lines A2780 and A2780cisR), with the IC50 values being in the submicromolar range. In comparison the analogous trishydroxythiophenolato compounds [(arene)2Ru2(S-p-C6H4OH)3]Cl (IC50 values around 100 μM) are much less cytotoxic. Thus, it would appear that the increased antiproliferative effect of the arene ruthenium complexes is due to the presence of the phenyl or toluyl substituents at the three thiolato bridges.