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Süss-Fink, Georg
Nom
Süss-Fink, Georg
Affiliation principale
Fonction
Professeur ordinaire
Email
georg.suess-fink@unine.ch
Identifiants
Résultat de la recherche
Voici les éléments 1 - 10 sur 10
- PublicationMétadonnées seulementHeterodinuclear Arene Ruthenium Complexes Containing a Glycine-Derived Phosphinoferrocene Carboxamide: Synthesis, Molecular Structure, Electrochemistry, and Catalytic Oxidation Activity in Aqueous Media(2012)
; ; ; Stepnicka, PetrThree series of heterodinuclear Ru-Fe complexes were synthesized from (?6-arene)ruthenium dichloride dimers and phosphinoferrocene ligands contg. glycine-based carboxamido substituents. The neutral complexes [(?6-arene)RuCl2(Ph2PfcCONHCH2CO2Me-?P)] (4, arene = benzene (a), p-cymene (b), hexamethylbenzene (c); fc = ferrocene-1,1'-diyl) were obtained by the bridge cleavage reaction of [(?6-arene)RuCl2]2 with Ph2PfcCONHCH2CO2Me (1) in CHCl3 soln. [(?6-P-cymene)RuCl2(Ph2PfcCONHCH2CONH2-?P)] (6b) was synthesized in the same way from Ph2PfcCONHCH2CONH2 (3); the prepn. of [(?6-p-cymene)RuCl2(Ph2PfcCONHCH2CO2H-?P)] (5b), featuring the ferrocene ligand in the free acid form (2), failed due to side reactions and isolation problems. [(?6-Arene)RuCl(MeCN)(1-?P)][PF6] (7a-c) and [(?6-arene)Ru(MeCN)2(1-?P)][PF6]2 (8a-c) were prepd. from 1 and the MeCN precursors [(?6-arene)RuCl(MeCN)2][PF6] and from 4a-c via halide removal with Ag[PF6] in MeCN soln., resp. Alternative synthetic routes to 7b and 8b were also studied. The compds. were fully characterized by elemental anal., multinuclear NMR, IR, and electrospray ionization mass spectra, and their electrochem. properties were studied by cyclic voltammetry at a Pt-disk electrode. The single-crystal x-ray analyses of two representatives (4b and 8b) revealed a pseudotetrahedral coordination geometry at the Ru centers and eclipsed conformations of the ferrocene moieties, with the substituents at the two cyclopentadienyl rings being anti with respect to each other. All complexes showed high activity for the catalytic oxidn. of secondary alcs. with tert-Bu hydroperoxide to give ketones in aq. media. The most active catalyst was obtained from the neutral p-cymene complex 4b, showing a catalytic turnover frequency of 13,200 h-1 at room temp. for the oxidn. of 1-phenylethanol at a substrate/catalyst ratio of 100,000. [on SciFinder(R)] - PublicationMétadonnées seulementHighly cytotoxic trithiophenolatodiruthenium complexes of the type [(?6-p-MeC6H4Pri)2Ru2(SC6H4-p-X)3]+: synthesis, molecular structure, electrochemistry, cytotoxicity, and glutathione oxidation potential(2012)
; ; - PublicationMétadonnées seulementSynthesis, Molecular Structure, and Anticancer Activity of Cationic Arene Ruthenium Metallarectangles(2009)
; Cationic arene ruthenium-based tetranuclear complexes comprising rectangular structures have been obtained from the dinuclear arene ruthenium complexes [Ru2(arene)2(OO?OO)2Cl2] (arene = p-cymene, hexamethylbenzene; OO?OO = 2,5-dihydroxy-1,4-benzoquinonato, 2,5-dichloro-1,4-benzoquinonato) by reaction with pyrazine or bipyridine linkers (N?N = pyrazine, 4,4'-bipyridine, 1,2-bis(4-pyridyl)ethylene) in methanol in the presence of AgO3SCF3, forming tetranuclear cations of general formula [Ru4(arene)4(N?N)2(OO?OO)2]4+. All complexes were isolated in good yield as triflate salts and were characterized by NMR and IR spectroscopy and studied by cyclic voltammetry. The cytotoxicities of the water-sol. compds. of the 4,4'-bipyridine and 1,2-bis(4-pyridyl)ethylene series have been established using ovarian A2780 cancer cells. The large rectangles incorporating 1,2-bis(4-pyridyl)ethylene linkers are ca. 5 times more cytotoxic (IC50 ? 6 ?M) than the 4,4'-bipyridine-contg. cations (IC50 ? 30 ?M). Structural characterization by x-ray diffraction of two representative compds., i.e., the triflate salts of [Ru4(hexamethylbenzene)4(4,4'-bipyridine)2(2,5-dihydroxy-1,4-benzoquinonato)2]4+and [Ru4(hexamethylbenzene)4(1,2-bis(4-pyridyl)ethylene)2(2,5-dichloro-1,4-benzoquinonato)2]4+, reveals differently sized cavities, different flexibilities, and different packing arrangements, suggesting a correlation between these structural properties and the obsd. cytotoxicities. [on SciFinder(R)] - PublicationAccès libreSawhorse-type diruthenium tetracarbonyl complexes containing porphyrin-derived ligands as highly selective photosensitizers for female reproductive cancer cells(2009)
; ; Juillerat-Jeanneret, LucienneDiruthenium 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)] - PublicationMétadonnées seulementFerrocenoyl Pyridine Arene Ruthenium Complexes with Anticancer Properties: Synthesis, Structure, Electrochemistry, and Cytotoxicity(2008)
; ; - PublicationMétadonnées seulementWater-soluble arene ruthenium complexes containing pyridinethiolato ligands: Synthesis, molecular structure, redox properties and anticancer activity of the cations [(?6-arene)Ru(p-SC5H4NH)3]2+(2008)
; ; - PublicationMétadonnées seulementMono and dinuclear rhodium, iridium and ruthenium complexes containing chelating 2,2'-bipyrimidine ligands: Synthesis, molecular structure, electrochemistry and catalytic properties(2007)
; ; - PublicationMétadonnées seulementMono and dinuclear iridium, rhodium and ruthenium complexes containing chelating carboxylato pyrazine ligands: Synthesis, molecular structure and electrochemistry(2007)
; ; - PublicationMétadonnées seulementSynthesis, structure and electrochemistry of cationic diruthenium complexes of the type [(N-N)2Ru2(CO)2(?-CO)2(?-OOCFc)]+ containing a ferrocenecarboxylato bridge and two chelating aromatic diimine ligands(2007)
; ; - PublicationMétadonnées seulementWater-soluble phenanthroline complexes of rhodium, iridium and ruthenium for the regeneration of NADH in the enzymatic reduction of ketones(2007)
; Stepnicka, PetrThe nicotinamide coenzyme NADH, consumed in enantioselective reduction of ketones catalysed by alcohol dehydrogenases, needs to be regenerated in order to maintain enzymatic activity. We therefore studied the catalytic potential of the cationic complexes [(eta(5)-(CMe5)-Me-5)Rh(NnN)Cl](+) (1: N boolean AND N = 1,10-phenanthrohne; 2: NnN = 5 -nitro-1, 10-phenanthroline; 3: NnN = 5-amino-1, 1 0-phenanthroline), [(eta(5)-C5Me5) Ir(N boolean AND N)CI](+) (4: N boolean AND N = 5-nitro-1, 10-phenanthroline) and [(eta(6)-C-6,Me-6)Ru(N boolean AND N)Cl](+) (5: NnN = 5-nitro-1,10-phenanthroline), isolated as the water-soluble chloride salts, for transfer hydrogenation of NAD(+) to give NADH in aqueous solution. The best results were obtained with rhodium complex 1, which gave catalytic turnover frequencies up to 2000 h(-1) in aqueous solution at pH 7 and 60 degrees C with sodium formate as the hydrogen source. When this NADH-regenerating catalytic system is combined with NADH-dependent enzymes, it is possible to chemoenzymatically reduce prochiral ketones such as acetophenone or 4-phenylbutan-2-one with high enantioselectivity. Combination of horse liver alcohol dehydrogenase (HLADH) or alcohol dehydrogenase from Rhodococcus sp. (S-ADH) with 1/formate as the NADH-regenerating system resulted in ee values up to 98 %, depending on the nature of the substrate and the enzyme. In order to explain the different catalytic activities, the electrochemical behaviour of complexes 1-5 has been studied. ((c) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)