Voici les éléments 1 - 8 sur 8
  • Publication
    Accès libre
    Increasing the size of metalla-assemblies to target the EPR-effect of tumors and solid cancers
    Le cancer, une maladie maligne, est l’une des principales causes de mortalité et de morbidité chez l’homme. Cependant, le ciblage sélectif des tissus cancéreux reste un défi. L'effet de perméabilité et de rétention accrue (effet EPR) est un phénomène naturel dans les tissus cancéreux solides qui est observé pour les structures moléculaires grandes et lourdes. Il constitue donc une voie de traitement appropriée pour cibler de manière sélective les tissus cancéreux, laissant intacts les tissus sains et réduisant les effets secondaires. Le ruthénium possède une activité anticancéreuse et est capable de former des assemblages macromoléculaires susceptibles d'exploiter l'effet EPR et de s'accumuler de manière sélective sur le site de la tumeur pour lutter localement contre la maladie. Le but de cette thèse est de préparer des métalla-assemblages, Cancer, a malignant disease, is one of the leading causes of mortality and morbidity among humans. However, selective targeting of cancerous tissue remains challenging. The enhanced permeability and retention effect (EPR-effect), a naturally occurring phenomenon in solid cancerous tissue, is a suitable treatment pathway to selectively target cancerous tissues, whereas healthy tissue remains untouched, and therefore side effects are reduced. This effect is observed for large and heavy molecular structures. Ruthenium has shown to possess anti-cancer activity, and is able to form macromolecular assemblies that could potentially exploit the EPR-effect and selectively accumulate on the tumor site to fight the disease locally. The goal of this thesis is to prepare macromolecular and multi-nuclear arene ruthenium metalla-assemblies to target the EPR-effect.
  • Publication
    Accès libre
    Synthesis, characterization and exploration of the catalytic, supramolecular and biological applications of dinuclear complexes
    (2013)
    Johnpeter, Justin Paul Raj
    ;
    The work presented in this thesis involves the synthesis and characterization of dinuclear ruthenium, rhodium and iridium complexes. The catalytic, supramolecular and biological applications of these dinuclear complexes will be discussed. In the first part, the synthesis of sawhorse-type diruthenium tetracarbonyl complexes and their catalytic applications in the supercritical carbon dioxide (scCO2) are presented. Synthesis of sawhorse-type molecular tweezers derived from pyrenyl and porphyrin carboxylic derivatives are presented in the second part. The host-guest interactions between the sawhorse-type molecular tweezers with different guest molecules will be discussed. In the final part, the anticancer potential of dinuclear ruthenium, rhodium and iridium complexes are evaluated with different cancer cell lines.
  • Publication
    Accès libre
    Permanent Encapsulation or Host–Guest Behavior of Aromatic Molecules in Hexanuclear Arene Ruthenium Prisms
    Cationic arene ruthenium metallaprisms of the general formula [Ru6(p-cymene)6(tpt)2(OO∩OO)3]6+ {tpt = 2,4,6-tris(4-pyridyl)-1,3,5-triazine; OO∩OO = 9,10-dioxo-9,10-dihydroanthracene-1,4-diolato [1]6+, 6,11-dioxo-6,11-dihydronaphthacene-5,12-diolato [2]6+} have been obtained from the corresponding dinuclear arene ruthenium complexes [Ru2(p-cymene)2(OO∩OO)Cl2] by reaction with tpt and silver trifluoromethanesulfonate. Aromatic molecules (phenanthrene, pyrene, triphenylene, coronene) present during the synthesis of these metallaprisms are permanently encapsulated to give carceplex systems. All empty cages ([1]6+ and [2]6+) and carceplex systems ([guest⊂1]6+ and [guest⊂2]6+) were isolated in good yield as trifluoromethanesulfonate salts and characterized by NMR, UV, and IR spectroscopy. The host–guest properties of [1]6+ and [2]6+ were studied in solution in the presence of small aromatic molecules (phenanthrene andpyrene). The stability constant of association (Ka) wasestimated by NMR spectroscopy for the following host–guest systems: [phenanthrene⊂1]6+, [pyrene⊂1]6+ and [phenanthrene⊂2]6+, [pyrene⊂2]6+. All Ka values were found to be larger than 2.0 × 104M–1 for these host–guest systems ([D3]acetonitrile, 21 °C).
  • Publication
    Accès libre
    Designing the Host-Guest Properties of Tetranuclear Arene Ruthenium Metalla-Rectangles to Accommodate a Pyrene Molecule
    (2010)
    Barry, Nicolas P. E.
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    Furrer, Julien
    ;
    ; ;
    Cationic tetranuclear arene ruthenium complexes of the general formula [Ru4(p-cymene)4(N∩N)2(dhnq)2]4+ comprising rectangular structures are obtained in methanol from the reaction of the dinuclear arene ruthenium precursor [Ru2(p-cymene)2(dhnq)2Cl2] (dhnq = 5,8-dihydroxy-1,4-naphthoquinonato) with pyrazine or bipyridine linkers [N∩N = pyrazine, 1; 4,4-bipyridine, 2; 1,2-bis(4-pyridyl)ethylene, 3] in the presence of AgCF3SO3. All complexes 1-3, isolated in good yield as triflate salts, have been characterised by NMR and IR spectroscopy. The interaction of these rectangular complexes with pyrene as a guest molecule has been studied in solution by various NMR techniques (1D, DOSY, ROESY). In [D3]acetonitrile, the pyrazine-containing metalla-rectangle 1 shows no meaningful interactions with pyrene. On the other hand, the 4,4-bipyridine- and 1,2-bis(4-pyridyl)ethylene-containing metalla-rectangles 2 and 3 clearly interact with pyrene in [D3]acetonitrile. DOSY measurements suggest that, in the case of [Ru4p-cymene)4(4,4-bipyridine)2(dhnq)2]4+ (2), the interactions occur on the outside of the rectangular assembly, while in the case of [Ru4(p-cymene)4{1,2-bis(4-pyridyl)ethylene}2 (dhnq)2]4+ (3), the pyrene molecule is found inside the hydrophobic cavity of the metalla-rectangle, thus giving rise to a host-guest system.
  • Publication
    Accès libre
    Arene Ruthenium Cages: Boxes Full of Surprises
    Self-assembly of polypyridyl ligands with dinuclear arene ruthenium building blocks bridged by chlorido, oxalato or benzoquinonato ligands has allowed the construction of a wide range of cationic metalla complexes possessing different architectures and functionalities: (i) metalla-rectangles showing host-guest possibilities and allowing intramolecular template-controlled photochemical [2 + 2] dimerisation reactions; (ii) metalla-prisms allowing encapsulation of molecules and giving rise to potential drug delivery systems; (iii) metalla-boxes that can be used to stabilise the formation of G-quadruplex DNA. This microreview covers the synthetic and structural aspects of these metalla complexes, as well as their most promising applications, with a particular focus on their potential biological applications.
  • Publication
    Accès libre
    Host-Guest Chemistry in the Hexanuclear (Arene)ruthenium Metalla-Prismatic Cage [Ru6(p-cymene)6(tpt)2(dhnq)3]6+
    (2009)
    Barry, Nicolas P.E.
    ;
    A large cationic triangular metalla-prism, [Ru6(p-cymene)6(tpt)2(dhnq)3]6+ ([1]6+), incorporating (p-cymene)ruthenium building blocks, bridged by 5,8-dihydroxy-1,4-naphthoquinonato (dhnq) ligands, and connected by two 2,4,6-tri(pyridin-4-yl)-1,3,5-triazine (tpt) subunits, allows encapsulation of various guest molecules. This cationic cage, isolated as its triflate salt, possesses a portal size smaller than its cavity, thus allowing both, permanent and temporary encapsulation of guest molecules. The host-guest properties of [1]6+ have been studied in solution in the presence of planar molecules [phenanthrene, pyrene, (pyren-1-ylmethyl)amine, Pt(acac)2, triphenylene]. The stability constant of association (Ka) was estimated by NMR spectroscopy for the following host-guest systems: [pyrene1]6+, [phenanthrene1]6+ and [(pyren-1-ylmethyl)amine1]6+. All Ka values were found to be larger than 2.4 × 104 M-1 for these host-guest systems ([D3]acetonitrile, 21 °C). The other two synthesised complexes, [Pt(acac)21]6+ and [triphenylene1]6+, were shown to act as carceplexes only.A large cationic triangular metalla-prism, [Ru6(p-cymene)6(tpt)2(dhnq)3]6+ ([1]6+), incorporating (p-cymene)ruthenium building blocks, bridged by 5,8-dihydroxy-1,4-naphthoquinonato (dhnq) ligands, and connected by two 2,4,6-tri(pyridin-4-yl)-1,3,5-triazine (tpt) subunits, allows encapsulation of various guest molecules. This cationic cage, isolated as its triflate salt, possesses a portal size smaller than its cavity, thus allowing both, permanent and temporary encapsulation of guest molecules. The host-guest properties of [1]6+ have been studied in solution in the presence of planar molecules [phenanthrene, pyrene, (pyren-1-ylmethyl)amine, Pt(acac)2, triphenylene]. The stability constant of association (Ka) was estimated by NMR spectroscopy for the following host-guest systems: [pyrene1]6+, [phenanthrene1]6+ and [(pyren-1-ylmethyl)amine1]6+. All Ka values were found to be larger than 2.4 × 104 M-1 for these host-guest systems ([D3]acetonitrile, 21 °C). The other two synthesised complexes, [Pt(acac)21]6+ and [triphenylene1]6+, were shown to act as carceplexes only.
  • Publication
    Accès libre
    Photochemical [2+2] cycloaddition of the olefinic double bonds in the supramolecular rectangle [Ru4(η6-p-cymene)4(μ-oxalato)2(μ-4,4′-bipyridylethylene)2]4+
    (2009)
    Barry, Nicolas P.E.
    ;
    Self-assembly of 4,4′-bipyridylethylene (bpe) bidentate connector with the dinuclear arene ruthenium clip [Ru2(η6-p-cymene)2(μ-oxalato)Cl2] in the presence of silver triflate affords the cationic organometallic rectangle [Ru4(η6-p-cymene)4(μ-oxalato)2(μ-bpe)2]4+ ([1][CF3SO3]4). Upon UV irradiation of a methanol solution of [1]4+, dimerisation of the olefinic double bonds of the two parallel bpe ligands occurs, thus giving rise to the [2+2] cycloaddition derivative [Ru4(η6-p-cymene)4(μ-oxalato)2(μ-tpcb)]4+ ([2][CF3SO3]4) (tpcb = tetrakis(4-pyridyl)cyclobutane). The [2+2] photodimerisation reaction was followed by 1H NMR spectroscopy. Moreover, the molecular structure of these two systems was deduced by one-dimensional and two-dimensional NMR experiments (1H, 13C, ROESY, COSY, HSQC). These data suggest the formation of only the rctt-tetrakis(4-pyridyl)cyclobutane isomer.
  • Publication
    Accès libre
    Encapsulation of Triphenylene Derivatives in the Hexanuclear Arene Ruthenium Metallo-Prismatic Cage [Ru6 (p-PriC6H4Me)6(tpt)2 (dhbq)3]6+ (tpt = 2,4,6-tri(pyridin-4-yl)-1,3,5-triazine, dhbq = 2,5-dihydroxy-1,4-benzoquinonato)
    (2008)
    Govindaswamy, Padavattan
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    Furrer, Julien
    ;
    ;
    A large cationic triangular metallo-prism, [Ru6(p-PriC6H4Me)6 (tpt)2 (dhbq)3]6+ (1)6+, incorporating p-cymene ruthenium building blocks, bridged by 2,5-dihydroxy-1,4-benzoquinonato (dhbq) ligands, and connected by two 2,4,6-tri(pyridin-4-yl)-1,3,5-triazine (tpt) subunits, allows the permanent encapsulation of the triphenylene derivatives hexahydroxytriphenylene, C18H6 (OH)6 and hexamethoxytriphenylene, C18H6 (OMe)6. These two cationic carceplex systems [C18H6 (OH)6⊂1]6+ and [C18H6 (OMe)6⊂1]6+ have been isolated as their triflate salts. The molecular structure of these systems has been established by one-dimensional 1H ROESY NMR experiments as well as by the single-crystal structure analysis of [C18H6 (OMe)6⊂1][O3SCF3]6.