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  • Publication
    Métadonnées seulement
    (?-p-Cymene)bis-(trichlorido-stannyl)(triethoxy-phosphine-?P)ruthenium(II)
    (2009)
    Shapovalov, Sergey S.
    ;
    In the title complex, [RuSn(2)(C(10)H(14))Cl(6)(C(6)H(15)O(3)P)], the Ru-Sn bond lengths [2.5619 (3) and 2.5669 (3) Å] are about 0.3 Å shorter than the sum of the covalent Ru and Sn radii (1.46 + 1.39 = 2.85 Å), in line with other structurally characterized arene ruthenium trichlorido-stannyl derivatives. The Ru(II) atom is surrounded by a para-cymene, a triethylphosphite and two trichloridostannyl ligands in a typical piano-stool coordination.[on SciFinder (R)]
  • Publication
    Accès libre
    Anticancer activity of osmium metalla-rectangles
    (2010)
    Barry, Nicolas P.E.
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    Edafe, Fabio
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    Paul Dyson
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    A series of cationic metalla-rectangles of the general formula [(p-cymene)4Os4(OO∩OO)2(NN)2]4+ have been obtained in methanol from the dinuclear arene osmium precursors [(p-cymene)2Os2 (OO∩OO)2Cl2] (OO∩OO = 2,5-dioxydo-1,4-benzoquinonato (dhbq), 2,5-dichloro-1,4-benzoquinonato (dcbq)) by reaction with bipyridine linkers (NN = 4,4′-bipyridine, 1,2-bis(4-pyridyl)ethylene) in the presence of AgCF3SO3. All complexes were isolated as triflate salts and characterised by NMR, IR and UV-visible spectroscopy. The cytotoxicities of the dinuclear and tetranuclear osmium complexes were established using ovarian A2780 cancer cell lines. The most active metalla-rectangle, [(p-cymene)4Os4(dhbq)2(4,4′-bipyridine)2]4+, shows an IC50 value of 5.7 μM (comparable to cisplatin) against A2780 cancer cells and 7.5 μM against the cisplatin resistant A2780cisR cells.
  • Publication
    Métadonnées seulement
    Double Targeting of Tumors with Pyrenyl-Modified Dendrimers Encapsulated in an Arene-Ruthenium Metallaprism
    (2011)
    Pitto-Barry, Anais
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    Barry, Nicolas P. E.
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    Zava, Olivier
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    Dyson, Paul J.
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    The self-assembly of 2,4,6-tris(pyridin-4-yl)-1,3,5-triazine (tpt) triangular panels with p-cymene-ruthenium building blocks and 5,8-dioxido-1,4-naphthoquinonato (donq) bridges, in the presence of pyrenyl-contg. dendrimers of different generations (P0, P1 and P2), affords the triangular prismatic host-guest compds. [Pn?Ru6(p-cymene)6(tpt)2(donq)3]6+ ([Pn?1]6+). The host-guest nature of these systems, with the pyrenyl moiety being encapsulated in the hydrophobic cavity of the cage and the dendritic functional group pointing outwards, was confirmed by NMR spectroscopy (1H, 2D and DOSY). The host-guest properties of these systems were studied in soln. by NMR and UV/Vis spectroscopic methods, allowing the detn. of their affinity consts. (Ka). Moreover, the ability of these water-sol. host-guest systems to carry the pyrenyl-contg. dendrimers into cancer cells was evaluated on human ovarian cancer cells. The host-guest systems are all more cytotoxic than the empty cage [1][CF3SO3]6 (IC50?4 ?M), with the most active compd., [P0?1][CF3SO3]6, being an order of magnitude more cytotoxic. [on SciFinder(R)]
  • Publication
    Métadonnées seulement
    Sawhorse-type diruthenium tetracarbonyl complexes containing porphyrin-derived ligands as highly selective photosensitizers for female reproductive cancer cells
    (2009)
    Schmitt, Frederic
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    Auzias, Mathieu
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    Stepnicka, Petr
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    Sei, Yoshihisa
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    Yamaguchi, Kentaro
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    ; ;
    Juillerat-Jeanneret, Lucienne
    Diruthenium tetracarbonyl complexes of the type [Ru2(CO)4(?2-?2-O2CR)2L2] contg. a Ru-Ru backbone with four equatorial carbonyl ligands, two carboxylato bridges, and two axial two-electron ligands in a sawhorse-like geometry have been synthesized with porphyrin-derived substituents in the axial ligands [1: R is CH3, L is 5-(4-pyridyl)-10,15,20-triphenyl-21,23H-porphyrin], in the bridging carboxylato ligands [2: RCO2H is 5-(4-carboxyphenyl)-10,15,20-triphenyl-21,23H-porphyrin, L is PPh3; 3: RCO2H is 5-(4-carboxyphenyl)-10,15,20-triphenyl-21,23H-porphyrin, L is 1,3,5-triaza-7-phosphatricyclo[3.3.1.1]decane], or in both positions [4: RCO2H is 5-(4-carboxyphenyl)-10,15,20-triphenyl-21,23H-porphyrin, L is 5-(4-pyridyl)-10,15,20-triphenyl-21,23H-porphyrin]. Compds. 1-3 were assessed on different types of human cancer cells and normal cells. Their uptake by cells was quantified by fluorescence and checked by fluorescence microscopy. These compds. were taken up by human HeLa cervix and A2780 and Ovcar ovarian carcinoma cells but not by normal cells and other cancer cell lines (A549 pulmonary, Me300 melanoma, PC3 and LnCap prostate, KB head and neck, MDAMB231 and MCF7 breast, or HT29 colon cancer cells). The compds. demonstrated no cytotoxicity in the absence of laser irradn. but exhibited good phototoxicities in HeLa and A2780 cells when exposed to laser light at 652 nm, displaying an LD50 between 1.5 and 6.5 J/cm2 in these two cell lines and more than 15 J/cm2 for the others. Thus, these types of porphyric compd. present specificity for cancer cell lines of the female reproductive system and not for normal cells; thus being promising new organometallic photosensitizers. [on SciFinder(R)]
  • Publication
    Métadonnées seulement
    Metallocene-Modified Uracils: Synthesis, Structure, and Biological Activity
    (2013)
    Kowalski, Konrad
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    Skiba, Joanna
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    Oehninger, Luciano
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    Ott, Ingo
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    Solecka, Jolanta
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    Rajnisz, Aleksandra
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    A new family of metallocene-uracil conjugates, including [3-(N1-uracilyl)-1-(ferrocenyl)]propene (2c), [3-(N1-thyminyl)-1-(ferrocenyl)]propene (3c), [3-(N1-(5-fluorouracilyl))-1-(ferrocenyl)]propene (4c), and [3-(N1-uracilyl)-1-(ruthenocenyl)]propene (5c), was obtained in three steps from (3-chloropropionyl)ferrocene and (3-chloropropionyl)ruthenocene, resp. The alkene complexes 2c-5c and their precursors: ketones 2a-5a and alcs. 2b-5b were characterized by NMR and IR spectroscopy, mass spectrometry, and elemental anal. The mol. structures of the intermediates 2b and 4a were detd. by single-crystal x-ray structure anal. In the solid state, two mols. of 2b or 4a form a dimeric structure, which is held together by strong H bonds. Compds. 2c-5c were also studied by cyclic voltammetry (CV). The ferrocenyl-uracil derivs. 2c-4c revealed reversible uncomplicated oxidns., whereas the cyclic voltammogram of the ruthenocenyl deriv. 5c showed an irreversible oxidn. Compds. 2c-5c were tested for their antiproliferative activity against human MCF-7 breast adenocarcinoma and HT-29 colon carcinoma cells. Compds. 3c-5c were moderately active against MCF-7 cancerous cells. Atomic absorption spectroscopy measurements on compd. 5c revealed that the ruthenocenyl deriv. is taken up by HT-29 cells in a time-dependent manner. However, the Ru cellular level remains relatively low. Compds. 2a-5a were also tested against Gram-pos. methicillin-sensitive Staphylococcus aureus (MSSA), methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Staphylococcus aureus (VRSA) and Staphylococcus epidermidis bacterial strains. Compd. 4a showed significant antibacterial activity against all bacterial strains, while compds. 2a and 3b were only moderately active. No antibacterial activity was found for the ruthenocenyl deriv. 5a. [on SciFinder(R)]
  • Publication
    Métadonnées seulement
    Synthesis and molecular structure of trinuclear mixed-metal cluster cations containing arene and hydrido ligands
    (2006)
    Romakh, Vladimir
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    ;
    The mixed-metal trinuclear cluster cations [H3Ru2(C6Me6)2Os(C6H6)(O)]+ (1), [H3Ru2(1,2,4,5-C6H2Me4)2Os(p-MeC6H4 iPr)(O)]+ (2) and [H3Ru2(1,2,4,5-C6H2Me4)2Os(C6H6)(O)]+ (3) have been synthesized from the corresponding dinuclear precursors [H3Ru2(arene)2]+ and the corresponding mononuclear complexes [Os(arene)(H2O)3]2+, isolated and characterized as the tetrafluoroborate and hexafluorophosphate salts. The cations 1, 2 and 3 are heteronuclear analogs of the cluster cation [H3Ru3(C6H6)(C6Me6)2(O)]+ that possesses a homonuclear metallic core. The single-crystal x-ray structure analyses of [1][BF4], [2][PF6] and [3][PF6] reveal an equiangular metal triangle despite the presence of an osmium atom in the metallic core. [on SciFinder(R)]
  • Publication
    Métadonnées seulement
    Ruthenium nanoparticles intercalated in hectorite: a reusable hydrogenation catalyst for benzene and toluene
    (2007) ;
    Mollwitz, Birgit
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    Dadras, Massoud
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    Laurenczy, Gabor
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    Meister, Annette
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    Meister, Goetz
    The cationic organometallic aqua complexes formed by hydrolysis of [(C6H6)RuCl2]2 in water, mainly [(C6H6)Ru(H2O)3]2+, intercalate into sodium hectorite by ion exchange, replacing the sodium cations between the anionic silicate layers. The yellow hectorite thus obtained reacts in ethanol with mol. hydrogen (50 bar, 100°) with decompn. of the organometallic aqua complexes to give a black material, in which ruthenium(0) nanoparticles (9-18 nm) are intercalated between the anionic silicate layers, the charges of which being balanced by hydronium cations. The black ruthenium-modified hectorite efficiently catalyzes the hydrogenation of benzene and toluene in ethanol (50 bar H2, 50°), the turnover frequencies attaining 7000 catalytic cycles per h. [on SciFinder(R)]