Vladimir B Arion

University of Vienna, Wien, Vienna, Austria

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Publications (169)519.52 Total impact

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    ABSTRACT: Bismuth-Gallium co-doped silica glass fiber preform was prepared from nano-porous silica xerogels using a conventional solution doping technique with a heterotrinuclear complex and subsequent sintering. Ga-connected optical Bismuth active center (BAC) was identified as the analogue of Al-connected BAC. Visible and infrared photoluminescence (PL) were investigated in a wide temperature range of 1.46 - 300 K. Based on the results of the continuous wave (CW) and time resolved (TR) spectroscopy we identify the centers emitting in the spectral region of 480 - 820 nm as Bi<sup>+</sup> ions. The near infrared (NIR) PL around 1100 nm consists of two bands. While the first one can be ascribed to the transition in Bi<sup>+</sup> ion, the second band is presumably associated to defects. We put in evidence the energy transfer (ET) between Bi<sup>+</sup> ions and the second NIR emitting center via quadrupole-quadrupole and dipole-quadrupole mechanisms of interactions. Finally, we propose the energy level diagram of Bi<sup>+</sup> ion interacting with this defect.
    Optics Express 03/2014; 22(5):5659-74. · 3.55 Impact Factor
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    ABSTRACT: The reactions of [Ru(NO)Cl5](2-) with glycine (Gly), l-alanine (l-Ala), l-valine (l-Val), l-proline (l-Pro), d-proline (d-Pro), l-serine (l-Ser), l-threonine (l-Thr), and l-tyrosine (l-Tyr) in n-butanol or n-propanol afforded eight new complexes (1-8) of the general formula [RuCl3(AA-H)(NO)](-), where AA = Gly, l-Ala, l-Val, l-Pro, d-Pro, l-Ser, l-Thr, and l-Tyr, respectively. The compounds were characterized by elemental analysis, electrospray ionization mass spectrometry (ESI-MS), (1)H NMR, UV-visible and ATR IR spectroscopy, cyclic voltammetry, and X-ray crystallography. X-ray crystallography studies have revealed that in all cases the same isomer type (from three theoretically possible) was isolated, namely mer(Cl),trans(NO,O)-[RuCl3(AA-H)(NO)], as was also recently reported for osmium analogues with Gly, l-Pro, and d-Pro (see Z. Anorg. Allg. Chem. 2013, 639, 1590-1597). Compounds 1, 4, 5, and 8 were investigated by ESI-MS with regard to their stability in aqueous solution and reactivity toward sodium ascorbate. In addition, cell culture experiments in three human cancer cell lines, namely, A549 (nonsmall cell lung carcinoma), CH1 (ovarian carcinoma), and SW480 (colon carcinoma), were performed, and the results are discussed in conjunction with the lipophilicity of compounds.
    Inorganic Chemistry 02/2014; · 4.59 Impact Factor
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    ABSTRACT: A series of seven new ruthenium(II)–arene complexes of general formula [Ru(η6-p-cymene)(L1−7)Cl], where L1−7 are fluoro, chloro, bromo or methyl derivatives of picolinic acid or isoquinoline-3-carboxylic acid has been synthesized and characterized by elemental analysis, IR, 1H and 13C NMR spectroscopy and ESI mass spectrometry. X-ray diffraction studies of two compounds showed the usual piano-stool geometry, with coordination of picolinato ligands through the pyridine nitrogen and the carboxylic group oxygen atom (N/COO− donor set). Cytotoxicity of complexes in vitro has been evaluated in three human tumor cell lines: cervix carcinoma (HeLa), melanoma (FemX), lung adenocarcinoma (A549) and one normal cell line (MRC-5). Complex with isoqinoline-3-carboxylic acid as ligand, exhibited significantly lower cytotoxic activity in normal cells (MRC-5) against high activity observed in panel of tumor cells and prominent cell type selectivity among tumor cells.
    Journal of Organometallic Chemistry 01/2014; 749:343-349. · 2.00 Impact Factor
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    ABSTRACT: Two p-cymene ruthenium chlorido complexes containing isobutyl (C1) and isoamyl (C2) esters of (S,S)-ethylenediamine-N,N′-di-2-(3-cyclohexyl)propanoic acid as ligands were prepared from p-cymene ruthenium dichloride dimer and corresponding ester. All compounds have been characterized by elemental analysis, IR, ESI-MS, 1H and 13C NMR spectroscopy. Single crystal X-ray structure diffraction analysis of C1 shows the usual piano-stool geometry of complexes, with coordination of ester ligand via nitrogen donor atoms. Ligands exhibit moderate anticancer activity (IC50 > 50 μM), while the complexes were significantly more cytotoxic towards various cancer cell lines, including B16, A375, HCT116, A549 and MCF7 cells (IC50 min.–max. 2.9–8.0 μM). We stress that cisplatin resistant HCT116 cell line was highly sensitive to the treatment with C1 and C2 (IC50 values: 4.4 and 5.5 μM versus IC50 > 120 μM for cisplatin). In parallel, primary fibroblasts-MRC-5 were remarkably less affected by these compounds.
    Journal of Organometallic Chemistry 01/2014; 749:142–149. · 2.00 Impact Factor
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    ABSTRACT: A new paullone-TEMPO conjugate and its copper(ii) complex inhibit RNR activity and show high antiproliferative activity in human cancer cell lines.
    Chemical Communications 09/2013; · 6.38 Impact Factor
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    ABSTRACT: Dicopper(II) and dizinc(II) complexes [Cu2((MeOOC)L(COO))(CH3COO)2] (1) and [Zn2((MeOOC)L(COO))(CH3COO)2] (2) were synthesized by reaction of Cu(CH3COO)2·H2O and Zn(CH3COO)2·2H2O with a new nonsymmetric dinucleating ligand (EtOOC)HL(COOEt) prepared by condensation of 6-hydrazinyl-11H-indolo[3,2-c]quinoline with diethyl-2,2'-((3-formyl-2-hydroxy-5-methylbenzyl)azanediyl)diacetate. The design and synthesis of this elaborate ligand was performed with the aim of increasing the aqueous solubility of indolo[3,2-c]quinolines, known as biologically active compounds, and investigating the antiproliferative activity in human cancer cell lines and the cellular distribution by exploring the intrinsic fluorescence of the indoloquinoline scaffold. The compounds have been comprehensively characterized by elemental analysis, spectroscopic methods (IR, UV-vis, (1)H and (13)C NMR spectroscopy), ESI mass spectrometry, magnetic susceptibility measurements, and UV-vis complex formation studies (for 1) as well as by X-ray crystallography (1 and 2). The antiproliferative activity of (EtOOC)HL(COOEt), 1, and 2 was determined by the MTT assay in three human cancer cell lines, namely, A549 (nonsmall cell lung carcinoma), CH1 (ovarian carcinoma), and SW480 (colon adenocarcinoma), yielding IC50 values in the micromolar concentration range and showing dependence on the cell line. The effect of metal coordination on cytotoxicity of (EtOOC)HL(COOEt) is also discussed. The subcellular distribution of (EtOOC)HL(COOEt) and 2 was investigated by fluorescence microscopy, revealing similar localization for both compounds in cytoplasmic structures.
    Inorganic Chemistry 08/2013; · 4.59 Impact Factor
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    ABSTRACT: Two multinuclear complexes [Fe6(μ3-O)2(μ4-O2)L10(OAc)2(H2O)2]·2.625Et2O·2.375H2O () and [Fe(III)11Cl(μ4-O)3(μ3-O)5L16(dmf)2.5(H2O)0.5]·Et2O·1.25dmf·3.8H2O (), where HL = 3,4,5-trimethoxybenzoic acid and dmf = dimethylformamide, have been prepared from trinuclear iron(iii) carboxylates via their structural rearrangement in dimethylformamide or diethyl ether-dimethylformamide 9 : 1, respectively, and slow vapor diffusion of diethyl ether into the reaction mixture. Both compounds have been characterized by X-ray diffraction, optical, Mössbauer spectroscopy, and magnetic measurements. Complex possesses a hexanuclear ferric peroxido-dioxido {Fe6(O2)(O)2}(12+) core unit, which adopts a recliner conformation, while complex contains an unprecedented {Fe11O8Cl}(16+) core, in which 9 ferric ions are six-coordinate and the remaining two are five-coordinate. Another structural feature of note of the undecanuclear core is the presence of a deformed cubane entity {Fe4(μ3-O)(μ4-O)3}(4+). Both complexes act as catalyst precursors for the oxidation of cyclohexane to cyclohexanol and cyclohexanone with aqueous H2O2, in the presence of pyrazinecarboxylic acid. Remarkable TONs and TOFs (the latter mainly for ) with concomitant quite good yields have been achieved under mild conditions. Moreover, exhibits remarkably high activity in an exceptionally short reaction time (45 min), being unprecedented for any metal catalyzed alkane oxidation by H2O2. The catalytic reactions proceed via Fenton type chemistry.
    Dalton Transactions 07/2013; 42:14388-14401. · 3.81 Impact Factor
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    ABSTRACT: Two proline-thiosemicarbazone bioconjugates with excellent aqueous solubility, namely, 3-methyl-(S)-pyrrolidine-2-carboxylate-2-formylpyridine thiosemicarbazone [l-Pro-FTSC or (S)-H2L] and 3-methyl-(R)-pyrrolidine-2-carboxylate-2-formylpyridine thiosemicarbazone [d-Pro-FTSC or (R)-H2L], have been synthesized and characterized by elemental analysis, one- and two-dimensional (1)H and (13)C NMR spectroscopy, and electrospray ionization mass spectrometry. The complexation behavior of l-Pro-FTSC with copper(II) in an aqueous solution and in a 30% (w/w) dimethyl sulfoxide/water mixture has been studied via pH potentiometry, UV-vis spectrophotometry, electron paramagnetic resonance, (1)H NMR spectroscopy, and spectrofluorimetry. By the reaction of copper(II) acetate with (S)-H2L and (R)-H2L in water, the complexes [Cu(S,R)-L] and [Cu(R,S)-L] have been synthesized and comprehensively characterized. An X-ray diffraction study of [Cu(S,R)-L] showed the formation of a square-pyramidal complex, with the bioconjugate acting as a pentadentate ligand. Both copper(II) complexes displayed antiproliferative activity in CH1 ovarian carcinoma cells and inhibited Topoisomerase IIα activity in a DNA plasmid relaxation assay.
    Inorganic Chemistry 07/2013; · 4.59 Impact Factor
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    ABSTRACT: The reactions of [Os(NO)Cl5]2– with glycine (GlyH), picolinic acid (PicoH), L-proline (L-ProH) and D-proline (D-ProH) afforded four novel complexes of the general formula [Os(NO)Cl3(AA)]–, where AA = Gly, Pico, L-Pro and D-Pro, respectively. X-ray diffraction studies have revealed that in all cases the same isomer type from three theoretically possible, has been isolated, namely mer(Cl), trans(NO, O)-[Os(NO)Cl3(AA)]–. Spectroscopic and electrochemical properties, behavior in aqueous solution and antiproliferative activity in three human cancer cell lines are also reported.
    Zeitschrift für anorganische und allgemeine Chemie 07/2013; 639(8-9):1590-1597. · 1.16 Impact Factor
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    ABSTRACT: Reactions of 5-tert-butyl-2-hydroxy-3-methylsulfanylbenzaldehyde S-methylisothiosemicarbazone and 5-tert-butyl-2-hydroxy-3-phenylsulfanylbenzaldehyde S-methylisothiosemicarbazone with pentane-2,4-dione (Hacac) and triethyl orthoformate in the presence of M(acac)2 as template source at 107 °C afforded metal complexes of the type M(II)L(1) and M(II)L(2), where M = Ni and Cu, with a new Schiff base ligand with thiomethyl (H2L(1)) and/or thiophenyl (H2L(2)) group in the ortho position of the phenolic moiety. Demetalation of NiL(1) in CHCl3 with HCl(g) afforded H2L(1). The latter reacts with Zn(OAc)2·2H2O with formation of ZnL(1). The effect of -SR groups and metal ion identity on stabilization of phenoxyl radicals generated electrochemically was studied in detail. A marked stabilization of phenoxyl radical was observed in one-electron-oxidized complexes [ML(2)](+) (M = Ni, Cu) at room temperature, as demonstrated by cyclic voltammetry, EPR spectroscopy, and UV-vis-NIR measurements. In solution, the oxidized CuL(2) and NiL(2) display intense low-energy NIR transitions consistent with their classification as metal-delocalized phenoxyl radical species. While the CuL(2) complex shows reversible reduction, reduction of NiL(2), CuL(1), and NiL(1) is irreversible. EPR measurements in conjunction with density functional theory calculations provided insights into the extent of electron delocalization as well as spin density in different redox states. The experimental room temperature spectroelectrochemical data can be reliably interpreted with the (3)[CuL(2)](+) and (2)[NiL(2)](+) oxidation ground states. The catalytic activity of synthesized complexes in the selective oxidations of alcohols has been studied as well. The remarkable efficiency is evident from the high yields of carbonyl products when employing both the CuL(2)/air/TEMPO and the CuL(2)/TBHP/MW(microwave-assisted) oxidation systems.
    Inorganic Chemistry 06/2013; · 4.59 Impact Factor
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    ABSTRACT: Organometallic Ru(arene)-peptide bioconjugates with potent in vitro anticancer activity are rare. We have prepared a conjugate of a Ru(arene) complex with the neuropeptide [Leu(5) ]-enkephalin. [Chlorido(η(6) -p-cymene)(5-oxo-κO-2-{(4-[(N-tyrosinyl-glycinyl-glycinyl-phenylalanyl-leucinyl-NH2 )propanamido]-1H-1,2,3-triazol-1-yl)methyl}-4H-pyronato-κO)ruthenium(II)] (8) shows antiproliferative activity in human ovarian carcinoma cells with an IC50 value as low as 13 μM, whereas the peptide or the Ru moiety alone are hardly cytotoxic. The conjugation strategy for linking the Ru(cym) (cym=η(6) -p-cymene) moiety to the peptide involved N-terminal modification of an alkyne-[Leu(5) ]-enkephalin with a 2-(azidomethyl)-5-hydroxy-4H-pyran-4-one linker, using Cu(I) -catalyzed alkyne-azide cycloaddition (CuAAC), and subsequent metallation with the Ru(cym) moiety. The ruthenium-bioconjugate was characterized by high resolution top-down electrospray ionization mass spectrometry (ESI-MS) with regard to peptide sequence, linker modification and metallation site. Notably, complete sequence coverage was obtained and the Ru(cym) moiety was confirmed to be coordinated to the pyronato linker. The ruthenium-bioconjugate was analyzed with respect to cytotoxicity-determining constituents, and through the bioconjugate models [{2-(azidomethyl)-5-oxo-κO-4H-pyronato-κO}chloride (η(6) -p-cymene)ruthenium(II)] (5) and [chlorido(η(6) -p-cymene){5-oxo-κO-2-([(4-(phenoxymethyl)-1H-1,2,3-triazol-1-yl]methyl)-4H-pyronato-κO}ruthenium(II)] (6) the Ru(cym) fragment with a triazole-carrying pyronato ligand was identified as the minimal unit required to achieve in vitro anticancer activity.
    Chemistry 05/2013; · 5.93 Impact Factor
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    Inorganic Chemistry 05/2013; · 4.59 Impact Factor
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    ABSTRACT: Ruthenium nitrosyl complexes of the general formulas (cation)(+)[cis-RuCl4(NO)(Hazole)](-), where (cation)(+) = (H2ind)(+), Hazole = 1H-indazole (Hind) (1c), (cation)(+) = (H2pz)(+), Hazole = 1H-pyrazole (Hpz) (2c), (cation)(+) = (H2bzim)(+), Hazole = 1H-benzimidazole (Hbzim) (3c), (cation)(+) = (H2im)(+), Hazole = 1H-imidazole (Him) (4c) and (cation)(+)[trans-RuCl4(NO)(Hazole)](-), where (cation)(+) = (H2ind)(+), Hazole = 1H-indazole (1t), (cation)(+) = (H2pz)(+), Hazole = 1H-pyrazole (2t), as well as osmium analogues of the general formulas (cation)(+)[cis-OsCl4(NO)(Hazole)](-), where (cation)(+) = (n-Bu4N)(+), Hazole =1H-indazole (5c), 1H-pyrazole (6c), 1H-benzimidazole (7c), 1H-imidazole (8c), (cation)(+) = Na(+); Hazole =1H-indazole (9c), 1H-benzimidazole (10c), (cation)(+) = (H2ind)(+), Hazole = 1H-indazole (11c), (cation)(+) = H2pz(+), Hazole = 1H-pyrazole (12c), (cation)(+) = (H2im)(+), Hazole = 1H-imidazole (13c), and (cation)(+)[trans-OsCl4(NO)(Hazole)](-), where (cation)(+) = n-Bu4N(+), Hazole = 1H-indazole (5t), 1H-pyrazole (6t), (cation)(+) = Na(+), Hazole = 1H-indazole (9t), (cation)(+) = (H2ind)(+), Hazole = 1H-indazole (11t), (cation)(+) = (H2pz)(+), Hazole = 1H-pyrazole (12t), have been synthesized. The compounds have been comprehensively characterized by elemental analysis, ESI mass spectrometry, spectroscopic techniques (IR, UV-vis, 1D and 2D NMR) and X-ray crystallography (1c·CHCl3, 1t·CHCl3, 2t, 3c, 6c, 6t, 8c). The antiproliferative activity of water-soluble compounds (1c, 1t, 3c, 4c and 9c, 9t, 10c, 11c, 11t, 12c, 12t, 13c) in the human cancer cell lines A549 (nonsmall cell lung carcinoma), CH1 (ovarian carcinoma), and SW480 (colon adenocarcinoma) has been assayed. The effects of metal (Ru vs Os), cis/trans isomerism, and azole heterocycle identity on cytotoxic potency and cell line selectivity have been elucidated. Ruthenium complexes (1c, 1t, 3c, and 4c) yielded IC50 values in the low micromolar concentration range. In contrast to most pairs of analogous ruthenium and osmium complexes known, they turned out to be considerably more cytotoxic than chemically related osmium complexes (9c, 9t, 10c, 11c, 11t, 12c, 12t, 13c). The IC50 values of Os/Ru homologs differ by factors (Os/Ru) of up to ∼110 and ∼410 in CH1 and SW480 cells, respectively. ESI-MS studies revealed that ascorbic acid may activate the ruthenium complexes leading to hydrolysis of one M-Cl bond, whereas the osmium analogues tend to be inert. The interaction with myoglobin suggests nonselective adduct formation; i.e., proteins may act as carriers for these compounds.
    Inorganic Chemistry 05/2013; · 4.59 Impact Factor
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    ABSTRACT: The electronic structure of the {Ru(NO)}6 fragment and the characterization of the oxidation state of ruthenium in mer,trans-[RuCl3(indazole)2(NO)] by X-ray diffraction, 1H, 13C, and 15N NMR, EPR, IR, and UV/Vis spectroscopy, cyclic voltammetry, magnetic susceptibility, and XANES/EXAFS as well as by theoretical DFT calculations are reported.
    European Journal of Inorganic Chemistry 04/2013; · 3.12 Impact Factor
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    ABSTRACT: A novel series of organometallic antitumour agents based on RuII and OsII complexes containing N-substituted 2-pyridinecarbothioamides (PCAs) has been synthesized and characterized. To the best of our knowledge, this is the first report of organometallic anticancer compounds with an S,N-bidentate ligand system. While the ligands showed activity as gastric mucosal protectants and low acute toxicity in vivo (J. Med. Chem., 1990, 33, 327–336), coordination leads to highly antiproliferative metallodrugs, depending on lipophilicity and steric demand, in colon carcinoma and non-small lung cancer cell lines with intrinsic chemoresistances. The most lipophilic and smallest congeners are the most effective with IC50 values in the low micromolar range. This new family of potential metallodrugs features exceptional stability in hydrochloric acid (60 mM), characterized by complete suppression of hydrolysis and low reactivity towards biological nucleophiles. Therefore, their unexpected aqueous chemistry renders this family of antiproliferative agents suitable for oral administration. An unprecedented feature is their ability to form transient thioketone-bridged dimers in aqueous solution upon hydrolysis, which is believed to minimize deactivation by biological nucleophiles. However, the biological effect seems to be caused by the monomer as observed with crystallographic studies of the nucleosome core particle (NCP), which revealed that [chlorido(h6-p-cymene)(N-phenyl-2-pyridinecarbothioamide)osmium(II)] chloride and [chlorido(h6-p-cymene)(N-fluorophenyl-2-pyridinecarbothioamide)osmium(II)] chloride react at two types of binding sites on the histone proteins. The adducts form at histidine side chains located on the nucleosome surface and the inner cleft of the nucleosome in the midst of an extensive histone– histone interface, suggesting interference with chromatin activity as a possible mode of action of these compounds. Additionally, ligand-based S / O exchange allows for a potential dual-mode of action by targeting DNA (J. Med. Chem., 2009, 52, 7753–7764). The quantitative estimates of drug-likeness (QED) for this family of compounds revealed a similar drug-likeness compared to erlotinib, tamoxifen, imatinib and sorafenib.
    Chemical Science 02/2013; 4:1837-. · 8.31 Impact Factor
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    ABSTRACT: Six novel ruthenium(II)- and osmium(II)-arene complexes with three modified indolo[3,2-c]quinolines have been synthesized in situ starting from 2-aminoindoloquinolines and 2-pyridinecarboxaldehyde in the presence of [M(p-cymene)Cl(2)](2) (M = Ru, Os) in ethanol. All complexes have been characterized by elemental analysis, spectroscopic techniques ((1)H, (13)C NMR, IR, UV-vis), and ESI mass spectrometry, while four complexes were investigated by X-ray diffraction. The complexes have been tested for antiproliferative activity in vitro in A549 (non-small cell lung), SW480 (colon), and CH1 (ovarian) human cancer cell lines and showed IC(50) values between 1.3 and >80 μM. The effects of Ru vs Os and modifications of the lactam unit on intermolecular interactions, antiproliferative activity, and cell cycle are reported. One ruthenium complex and its osmium analogue have been studied for anticancer activity in vivo applied both intraperitoneally and orally against the murine colon carcinoma model CT-26. Interestingly, the osmium(II) complex displayed significant growth-inhibitory activity in contrast to its ruthenium counterpart, providing stimuli for further investigation of this class of compounds as potential antitumor drugs.
    Organometallics 02/2013; 32(3):903-914. · 4.15 Impact Factor
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    ABSTRACT: Keywords: Copper(II) complexes / Schiff bases / Chelates / Disiloxane unit / Alcohols / Catalytic oxidation Mononuclear copper(II) salen-type Schiff base complexes, Cu II L 1–5 [H 2 L 1 to H 2 L 5 = tetradentate N,N,O,O ligands de-rived from 2-hydroxybenzaldehyde, 2,4-dihydroxybenz-aldehyde, 3,5-dibromo-2-hydroxybenzaldehyde, 2-hydroxy-5-nitrobenzaldehyde, 5-chloro-2-hydroxybenzaldehyde and 1,3-bis(3-aminopropyl)tetramethyldisiloxane, respectively] were prepared in situ in the presence of a copper(II) salt or by direct complexation between a copper(II) salt and a pre-synthesised Schiff base. The compounds {CuL 1 , CuL 1 ·0.5Py, CuL 2 ·0.375CH 2 Cl 2 , (CuL 3)[Cu(4-Me-Py) 4 Cl]Cl·2H 2 O, CuL 4 , CuL 4 ·CHCl 3 and CuL 5 , as well as the isolated ligand H 2 L 3 } were characterised by elemental analysis, spectroscopic methods (IR, UV/Vis, 1 H NMR, EPR) and X-ray crystallogra-phy. The formation of a 12-membered central chelate ring in these complexes is effected by the tetramethyldisiloxane unit, which separates the aliphatic chains, thus significantly reducing the mechanical strain in such a chelate ring. We
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    ABSTRACT: Six novel ruthenium(II)- and osmium(II)-arene complexes with indoloquinoline modified ligands containing methyl and halo substituents in position 8 of the molecule backbone have been synthesised and comprehensively characterised by spectroscopic methods (1H, 13C NMR, UV-Vis), ESI mass spectrometry and X-ray crystallography. Binding of indoloquinolines to a metal-arene scaffold makes the products soluble enough in biological media to allow for assaying their antiproliferative activity. The complexes were tested in three human cancer cell lines, namely A549 (non-small cell lung cancer), SW480 (colon carcinoma) and CH1 (ovarian carcinoma), yielding IC50 values in the 10-6-10-7 M concentration range after continuous exposure for 96 h. Compounds with halo substituents in position 8 are more effective cytotoxic agents in vitro than the previously reported species halogenated in position 2 of the indoloquinoline backbone. High antiproliferative activity of both series of substances may be due at least in part to their potential to act as DNA intercalators.
    Inorganica Chimica Acta 12/2012; 393(7):252-260. · 1.69 Impact Factor
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    ABSTRACT: Ru(II)(arene) complexes have been shown to be promising anticancer agents, capable of overcoming major drawbacks of currently used chemotherapeutics. We have synthesized Ru(II)(η(6)-arene) compounds carrying bioactive flavonol ligands with the aim to obtain multi-targeted anticancer agents. In order to validate this concept, studies on the mode of action of the complexes were conducted which indicated that they are form covalent bonds to DNA, have only minor impact on the cell cycle but inhibit CDK2 and topoisomerase IIα in vitro. The cytotoxic activity was determined in human cancer cell lines, resulting in very low IC50 values as compared to other Ru(II)(η(6)arene) complexes and showing a structure-activity relationship dependent on the substitution pattern of the flavonol ligand. Furthermore, the inhibition of cell growth correlates well with the topoisomerase inhibitory activity. Compared to the flavonol ligands, the Ru(II)(η(6)-p-cymene) complexes are more potent antiproliferative agents, which can be explained by potential multi-targeted properties.
    Journal of Medicinal Chemistry 11/2012; · 5.61 Impact Factor
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    Symposium in Honour of Ramôa Ribeiro, Instituto Superior Técnico, Lisboa; 10/2012

Publication Stats

943 Citations
519.52 Total Impact Points


  • 2002–2014
    • University of Vienna
      • • Institut für Anorganische Chemie
      • • Faculty of Chemistry
      • • Department of Organic Chemistry
      Wien, Vienna, Austria
    • Laboratoire de Chimie de Coordination.
      Tolosa de Llenguadoc, Midi-Pyrénées, France
  • 2011
    • University of Szeged
      • Department of Inorganic and Analytical Chemistry
      Szeged, Csongrad megye, Hungary
    • Kasetsart University
      • Faculty of Science
      Bangkok, Bangkok, Thailand
  • 2009
    • University of Belgrade
      • Faculty of Chemistry
      Belgrade, SE, Serbia
  • 2007
    • National Academy of Sciences of Ukraine
      • A. V. Bogatsky Physico-Chemical Institute
      Kiev, Misto Kyyiv, Ukraine
  • 2006
    • Russian Academy of Sciences
      • Vernadsky Institute of Geochemistry and Analytical Chemistry
      Moscow, Moscow, Russia
  • 2004
    • Instituto Técnico y Cultural
      Santa Clara de Portugal, Michoacán, Mexico