Abstract α-Pyridyl thiosemicarbazones (TSC) such as Triapine (3AP) and Dp44mT are a promising class of anticancer agents. Contrary to Triapine, Dp44mT showed a pronounced synergism with CuII, which may be due to the generation of reactive oxygen species (ROS) by Dp44mT-bound CuII ions. However, in the intracellular environment, CuII complexes have to cope with glutathione (GSH), a relevant CuII...[En savoir plus]
Abstract The redox activity of Cu ions bound to the amyloid-β (Aβ) peptide is implicated as a source of oxidative stress in the context of Alzheimer's disease. In order to explain the efficient redox cycling between Cu(II)-Aβ (distorted square pyramidal) and Cu(I)-Aβ (digonal) resting states, the existence of a low-populated "in-between" state, prone to bind Cu in both oxidation states, has been...[En savoir plus]
Abstract We report herein a domino reaction to construct 2-amido-5-fluoropyrroles from CF3-substituted N-allenamides. The in situ generated gem-difluorinated ene-ynamides derived from CF3-substituted N-allenamides, when subjected to silver catalysis with a primary amine, undergo simultaneous hydroamination of the ynamide moiety followed by a 5-endo-trig addition/β-fluoride elimination sequence,...[En savoir plus]
Abstract 3,3',3''-(Benzene-1,3,5-triyl)tris(1-phenyl-1H-benzo[e][1], [2], [4]triazin-4-yl) (1) is a C3-symmetrical triradical comprised of three Blatter radical units connected at the 1, 3, 5 positions of a central trimethylenebenzene core. This triradical has an excellent air, moisture, and thermal stability. Single-crystal XRD indicates that triradical 1 adopts a propeller-like geometry with...[En savoir plus]
Abstract Potential inversion refers to the situation where a protein cofactor or a synthetic molecule can be oxidized or reduced twice in a cooperative manner; that is, the second electron transfer is easier than the first. This property is very important regarding the catalytic mechanism of enzymes that bifurcate electrons and the properties of bidirectional redox molecular catalysts that...[En savoir plus]
Abstract Two novel compounds isolated from an amber sample from the Santonian of Piolenc (Vaucluse, SE France) were identified using nuclear magnetic resonance and high-resolution mass spectrometry as sulfurized analogues of diterpenic acids from the isopimaric series originating from ancient conifers possibly related to the Cupressaceae family. These two compounds are members of a diterpenoid...[En savoir plus]
Abstract We report the synthesis of new vanadyl porphyrins bearing peripheral coordination sites. By using palladium(II) or platinum(II) as connecting ions, porphyrin dimers were isolated and characterized by X-ray crystallography. These paramagnetic species were studied by electronic spectroscopy and continuous wave electron paramagnetic resonance (CW EPR). Large bathochromic shifts were...[En savoir plus]