Résultat de la recherche
Organometallic Cages as Vehicles for Intracellular Release of Photosensitizers
Water-soluble metalla-cages were used to deliver hydrophobic porphin molecules to cancer cells. After internalization, the photosensitizer was photoactivated, significantly increasing the cytotoxicity in cells. During the transport, the photosensitizer remains nonreactive to light, offering a new strategy to tackle overall photosensitization, a limitation often encountered in photodynamic therapy.
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).