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  • Publication
    Métadonnées seulement
    Arene ruthenium and pentamethylcyclopentadienyl rhodium and iridium complexes containing N,O-chelating ligands derived from piroxicam: Synthesis, molecular structure and cytotoxicity
    (2014)
    Raja, Mathiyazhagan Ulaganatha
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    Riedel, Tina
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    Dyson, Paul J.
    The non-steroidal anti-inflammatory and anti-arthritic drug piroxicam (LH) reacts with arene ruthenium dichloride dimers in refluxing dichloromethane to give the complexes [(?6-arene)Ru(?2-N,O-L)Cl] (3: arene = C6H5Me, 4: arene = p-MeC6H4Pri, 5: arene = C6Me6). The reaction seems to proceed via the intermediates [(?6-arene)Ru(N-LH)Cl2], which can be obsd. for arene = C6H5Me (1) and isolated in the case of arene = p-MeC6H4Pri (2). The analogous reaction with pentamethylcyclopentadienyl rhodium and iridium gives the complexes [(?5-C5Me5)M(?2-N,O-L)Cl] (6: M = Rh, 7: M = Ir). The single-crystal x-ray structure analyses of the p-cymene ruthenium derivs. 4 and 2 show the metal atom in the archetypical piano stool geometry; in 4 the piroxicamato ligand is coordinated in a bidentate fashion through the pyridine nitrogen atom and the enolic oxygen atom, while in 2 the intact piroxicam ligand is coordinated in a monodentate fashion through the pyridine nitrogen atom. The piroxicamato complexes 3-5 are weakly cytotoxic towards human ovarian cancer cells. [on SciFinder(R)]
  • Publication
    Métadonnées seulement
    Synthesis, molecular structure, computational study and in vitro anticancer activity of dinuclear thiolato-bridged pentamethylcyclopentadienyl Rh(III) and Ir(III) complexes
    (2013)
    Gupta, Gajendra
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    Murray, Benjamin S.
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    Dyson, Paul J.
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    Fabre, Gabin
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    Trouillas, Patrick
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    Giannini, Federico
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    Furrer, Julien
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    Neutral dinuclear dithiolato-bridged pentamethylcyclopentadienyl Rh(III) complexes (C5Me5)2Rh2(?-SR)2Cl2 (R = CH2Ph, 1; R = CH2CH2Ph, 2) and cationic dinuclear trithiolato-bridged pentamethylcyclopentadienyl Rh(III) and Ir(III) complexes [(C5Me5)2M2(?-SR)3]+ (M = Rh, R = CH2Ph, 3; M = Rh, R = CH2CH2Ph, 5; M = Rh, R = CH2C6H4-p-tBu, 7: M = Ir, R = CH2Ph, 4; M = Ir, R = CH2CH2Ph, 6; M = Ir, R = CH2C6H4-p-tBu, 8) were synthesized from the chloro-bridged pentamethylcyclopentadienyl Rh(III) and Ir(III) dimers (C5Me5)2M2(?-Cl)2Cl2 by reaction with the corresponding thiol deriv. (RSH). Complexes 3-8 were isolated as chloride salts. All complexes were obtained in good yield and were fully characterized by spectroscopic methods. The mol. structures of the neutral complexes (1 and 2) show interesting features: the two Rh atoms are bridged by two thiolato ligands with no metal-metal bonds and the pentamethylcyclopentadienyl and chlorido ligands are oriented syn to each other, an uncommon conformation for such dinuclear complexes. These structural features were rationalized using DFT calcns. Addnl., the antiproliferative activity of the complexes was evaluated against the cancerous A2780 (cisplatin sensitive) and A2780cisR (cisplatin resistant) human ovarian cell lines and on the noncancerous HEK293 human embryonic kidney cells. All complexes are active and the cationic Ir complexes 4, 6 and 8 are particularly cytotoxic, with IC50 values in the nanomolar range (IC50 < 0.1 ?M). The catalytic activity of the complexes for the oxidn. of glutathione (GSH) to GSSG was evaluated by NMR spectroscopy. [on SciFinder(R)]
  • Publication
    Métadonnées seulement
    Arene ruthenium dichloro complexes containing isonicotinic ester ligands: Synthesis, molecular structure and cytotoxicity
    (2013)
    Khan, Farooq-Ahmad
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    Zava, Olivier
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    Dyson, Paul J.
    A series of p-cymene ruthenium dichloro complexes contg. isonicotinic ester ligands, [(arene)RuCl2NC5H4-4-COO-C6H4-p-O-(CH2)n-CH3] (n = 1: 1, n = 3: 2, n = 5: 3, n = 7: 4, n = 9: 5, n = 11: 6, n = 13: 7, n = 15: 8), were prepd. from p-cymene ruthenium dichloro dimer and the corresponding isonicotinic ester ligand. The single-crystal x-ray anal. of 1 shows the mol. to adopt the usual pseudo-tetrahedral piano-stool geometry, the isonicotinic ester ligand being coordinated through the nitrogen atom. The cytotoxicity of all complexes and of the free ligands was studied towards human ovarian cancer cells; high activities were obsd. only for n = 9 (presenting a chain with ten carbon atoms), both as far as the free ligands and the complexes are concerned. Based on this result, a new isonicotinic ester ligand with a C10 substituent contg. a terminal alc. function, NC5H4-4-COO-C6H4-p-O-(CH2)10-OH, was synthesized by a four-step method, and arene ruthenium complexes thereof, [(arene)RuCl2NC5H4-4-COO-C6H4-p-O-(CH2)10-OH] (arene = C6H6: 9a, arene = p-MeC6H4Pri: 9b, arene = C6Me6: 9c) were prepd. The complexes 9a and 9b show indeed remarkable anticancer activities, the IC50 values for human ovarian cancer cells being in the submicromolar range. The highest cytotoxicity was obsd. for complex 9b, with IC50 values of 0.18 ?M for A2780 and 3.04 ?M for the cisplatin-resistant mutant A2780cisR. [on SciFinder(R)]
  • 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
    Métadonnées seulement
    Highly cytotoxic diruthenium trithiolato complexes of the type [(?6-p-MeC6H4Pri)2Ru2(?2-SR)3]+: synthesis, characterization, molecular structure and in vitro anticancer activity
    (2013)
    Giannini, Federico
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    Paul, Lydia E. H.
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    Furrer, Julien
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    Cationic dinuclear p-cymene Ru complexes bridged by three thiophenolato ligands contg. various substituents mainly in meta and ortho positions, [(?6-p-MeC6H4Pri)2Ru2(?2-SR)3]+ (R = 3-C6H4Me: 1; R = 3-C6H4OMe: 2; R = 3-C6H4OEt: 3; R = 3-C6H4CF3: 4; R = 3-C6H4NH2: 5; R = 3-C6H4Cl: 6; R = 2-C6H4Me: 7; R = 2-C6H4OMe: 8; R = 2-C6H4Pri: 9; R = 2-C6H4CF3: 10; R = npt: 11 (npt = 2-naphthyl); R = mco: 12 (mco = 4-methylcoumarinyl); R = 3,5-C6H3Me2: 13; R = 3,5-C6H3(CF3)2: 14; R = 3,5-C6H3Cl2: 15; R = 3,4-C6H3(OMe)2: 16), were prepd. from the reaction of the neutral p-cymene diruthenium dichloride dimer, [(?6-p-MeC6H4Pri)2Ru2Cl4], with the corresponding thiophenol RSH. All cationic complexes were isolated as their chloride salts and fully characterized by spectroscopic and anal. methods. The mol. structures of 10 and 15 were solved by a single-crystal x-ray structure anal. of [10]Cl and [15]Cl, which show that the two Ru atoms adopt a pseudo-octahedral geometry without a metal-metal bond in accordance with the noble gas rule. All complexes are highly cytotoxic towards human ovarian cancer cells, the IC50 values being mostly in the nanomolar range. Complex 9 shows the highest cytotoxicity with an IC50 value of 0.03 ?M towards the A2780 cell line and the cisplatin-resistant mutant A2780cisR. The cytotoxicity of these complexes, which belong to the most active Ru anticancer compds. reported so far, can be correlated with the lipophilicity of the corresponding thiols. In comparison with the previous series, the positions of the substituents in the thiophenolato bridges are not as important as the nature of the substituents, alkyl substituents being the best ones in line with their lipophilic character. [on SciFinder(R)]
  • Publication
    Métadonnées seulement
    Synthesis, characterisation and in vitro anticancer activity of hexanuclear thiolato-bridged arene ruthenium metalla-prisms
    (2013)
    Furrer, Mona A.
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    Denoyelle-Di-Muro, Emmanuel
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    Trouillas, Patrick
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    Giannini, Federico
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    Furrer, Julien
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    Clavel, Catherine M.
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    Dyson, Paul J.
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    Hexanuclear hexacationic thiolato-bridged arene ruthenium metalla-prisms of the general formula [[(?6-p-cymene)Ru]6(?-SR)6(?3-tpt)2][OTf]6 (R = CH2Ph, CH2C6H4-p-tBu, CH2CH2Ph; tpt = 2,4,6-tri-4-pyridyl-1,3,5-triazine), obtained from the self-assembly of dinuclear precursors [(p-cymene)2Ru2(?-SR)2Cl2] with tpt and AgCF3SO3, have been isolated and fully characterized as triflate salts. The metalla-prisms are highly cytotoxic against human ovarian cancer cells, esp. towards the cisplatin-resistant cell line A2780cisR (IC50
  • Publication
    Métadonnées seulement
    Different coordination modes of dipyridyl ketimine ligands in cationic arene ruthenium complexes
    (2013)
    Raja, Mathiyazhagan Ulaganatha
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    2,2'-Dipyridyl-N-arylimines L (L1 = 2,4,6-trimethyl(di-2-pyridylmethylene)aniline, L2 = 2,6-diisopropyl(di-2-pyridylmethylene)aniline) react with arene ruthenium dichloride dimer in methanol to give cationic arene ruthenium complexes of the general type [(arene)Ru(?2-N,N-L)Cl]+ (arene = C6H6, p-MeC6H4Pri). Two coordination modes of the chelating ligands N,N-L are obsd. In the major isomer, the ketimine nitrogen atom and one of the two pyridine nitrogen atoms are coordinated to ruthenium, while in the minor isomer the two pyridine nitrogen atoms coordinate to the metal center. In the case of L1, the minor isomer of the p-cymene ruthenium chloro complex could be isolated as the tetrafluoroborate salt and characterized by single crystal X-ray anal. The mol. structure of the major isomer was detd. by X-ray crystallog. in the case of the tetraphenylborate salt of the benzene ruthenium chloro deriv. In both structures, the ruthenium atom shows the expected pseudo-tetrahedral coordination geometry. [on SciFinder(R)]
  • Publication
    Métadonnées seulement
    Highly cytotoxic trithiophenolatodiruthenium complexes of the type [(?6-p-MeC6H4Pri)2Ru2(SC6H4-p-X)3]+: synthesis, molecular structure, electrochemistry, cytotoxicity, and glutathione oxidation potential
    (2012)
    Giannini, Federico
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    Furrer, Julien
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    Ibao, Anne-Flore
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    Zava, Olivier
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    Baquie, Mathurin
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    Dyson, Paul J.
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    Stepnicka, Petr
    A series of cationic binuclear areneruthenium tris(arenethiolato)-bridged complexes [(?6-p-cymene)2Ru2(?-SC6H4-p-X)3]+ (1-11; X = H, Me, Ph, Br, OH, NO2, OMe, CF3, F, iPr, tBu) were prepd. by complexation of the chloride-bridged dimer [(?6-p-cymene)2Ru2(?-Cl)2Cl2] with the corresponding thiols, isolated as the chloride salts, and further studied for their electrochem. properties, cytotoxicity towards human ovarian cancer cells, and catalytic activity for glutathione (GSH) oxidn. Complex 1 was also compared with the benzene and hexamethylbenzene analogs [(?6-C6H6)2Ru2(?-SC6H5)3]+ (12) and [(?6-C6Me6)2Ru2(?-SC6H5)3]+ (13). The most active compd. [11]Cl was structurally studied by single-crystal x-ray diffraction anal. The concns. corresponding to 50% inhibition of cancer cell growth (IC50 values) in the A2780 and A2780cisR cell lines of these complexes except for 6 were in the submicromolar range, complex 11 showing an IC50 value of 0.03 ?M in both cell lines. The high in vitro anticancer activity of these complexes may be at least partially due to their catalytic potential for the oxidn. of GSH, although there is no clear correlation between the IC50 values and the turnover frequencies at about 50% conversion. However, the cytotoxicity is tentatively correlated to the physicochem. properties of the compds. detd. by the electronic influence of the substituents X (Hammett consts. ?p) and the lipophilicity of the thiols p-XC6H4SH (calcd. log P parameters). [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
    Métadonnées seulement
    Heteronuclear complexes containing the N,N'-di(2-pyridyl)amidocarboxylferrocene ligand
    (2012)
    Auzias, Mathieu
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    The ferrocene-derived ligand (NC5H4)2NOC-C5H4FeC5H5 reacts with arene ruthenium complexes [(?6-arene)RuCl2]2 to give the cationic complexes [(?6-p-iPrC6H4Me)RuCl{(NC5H4)2NOC-C5H4FeC5H5}]+ (1) and [(?6-C6Me6)RuCl{(NC5H4)2NOC-C5H4FeC5H5}]+ (2), isolated as the hexafluorophosphate and tetrafluoroborate salts, resp., while the reaction with K2PtCl4 yields the neutral complex PtCl2{(NC5H4)2NOC-C5H4FeC5H5} (3). The mol. structures of 2 and 3 were confirmed by single-crystal x-ray diffraction. [on SciFinder(R)]