Search results for "Complexes."
showing 10 items of 857 documents
Towards Iron(II) Complexes with Octahedral Geometry: Synthesis, Structure and Photophysical Properties
2020
The control of ligand-field splitting in iron (II) complexes is critical to slow down the metal-to-ligand charge transfer (MLCT)-excited states deactivation pathways. The gap between the metal-centered states is maximal when the coordination sphere of the complex approaches an ideal octahedral geometry. Two new iron(II) complexes (C1 and C2), prepared from pyridylNHC and pyridylquinoline type ligands, respectively, have a near-perfect octahedral coordination of the metal. The photophysics of the complexes have been further investigated by means of ultrafast spectroscopy and TD-DFT modeling. For C1, it is shown that&mdash
Polyamines and applications. A look at the first workshop in linear and cyclic polyamines chemistry
2008
Given their versatile coordination properties, cyclic and linear polyamines are the subject of numerous worksin many research groups. This great interest is mainly related to their use in diverse fields such as removalof metals from liquids, purification of gases, application in catalysis, in sensors, as well as in various probesfor medical applications. This paper summarizes recent results obtained by the French research groupswhich attended the first ìworkshop in linear and cyclic polyamines chemistryî.
Moment-angle complexes and complexe manifolds
2010
The aim of this thesis is to extend the results of the article [B-M] on the relations between moment-angle complexes and complex manifolds. We will focus here on moment-angle complexes defined by a simplicial (not only polytopal) decomposition of the sphere. We will also seek to use the relationship between these two kinds of objects to be understand the topology of several complex manifolds. [B-M] F.Bosio, L.Meersseman, Real quadrics in Cn, complex manifolds and polytopes, Acta Mathematica, 197 (2006), n° 1, 53 -- 127.
Famille à un paramètre de coniques utilisant des courbes de Bézier à poids complexes
2019
The paper deals with conics in a rational Bézier representation based on mass points where the weights are complex numbers here. A special representation of conics using weighted points and vectors offers a calculus flexibility in the handle elementary geometrical transformations as rotations, homotheties and direct similarity transformations. Some examples are proposed to the reader.
New molecular aspects of regulation of mitochondrial activity by fenofibrate and fasting
2000
Abstract Fenofibrate and fasting are known to regulate several genes involved in lipid metabolism in a similar way. In this study measuring several mitochondrial enzyme activities, we demonstrate that, in contrast to citrate synthase and complex II, cytochrome c oxidase (COX) is a specific target of these two treatments. In mouse liver organelles, Western blot experiments indicated that mitochondrial levels of p43, a mitochondrial T3 receptor, and mitochondrial peroxisome proliferator activated receptor (mt-PPAR), previously described as a dimeric partner of p43 in the organelle, are increased by both fenofibrate and fasting. In addition, in PPARα-deficient mice, this influence was abolishe…
Engineering a Saccharomyces cerevisiae Wine Yeast That Exhibits Reduced Ethanol Production during Fermentation under Controlled Microoxygenation Cond…
2006
ABSTRACTWe recently showed that expressing an H2O-NADH oxidase inSaccharomyces cerevisiaedrastically reduces the intracellular NADH concentration and substantially alters the distribution of metabolic fluxes in the cell. Although the engineered strain produces a reduced amount of ethanol, a high level of acetaldehyde accumulates early in the process (1 g/liter), impairing growth and fermentation performance. To overcome these undesirable effects, we carried out a comprehensive analysis of the impact of oxygen on the metabolic network of the same NADH oxidase-expressing strain. While reducing the oxygen transfer rate led to a gradual recovery of the growth and fermentation performance, its i…
Oxidovanadium(v) complexes with l-proline-based amino acid phenolates
2019
L-proline was used to prepare chiral, tridentate amino acid phenol proligands H2L1—4. These proligands react with vanadium precursors VO(acac)2, VOSO4 ∙ 5 H2O and VO(OPr)3 in methanol to form the corresponding oxidoalkoxidovanadium(V) complexes 1—4. The complexes crystallize from methanol, and are octahedrally coordinated with a general formula [VO(L1—4)(OMe)(MeOH)]. In solution, however, they adopt several different conformations or isomeric structures depending on the solvent. peerReviewed
Solvent-dependent hypsochromic shift in the imidazole based complex [Cu(µ2-SO4)(Im)4] and ameliorative effects on breast cancer-induced bone metastas…
2023
A sulfate-bridged complex [Cu(µ2-SO4)(Im)4] (1) was prepared and structurally characterized, where Im: imidazole. The X-ray structure analysis reveals that 1 crystallizes in the monoclinic system with space group C2/c. The octahedral coordination around the metal center is made up of four distinct imine nitrogen atoms in the equatorial plane, and two sulfate oxygen atoms occupying the axial sites. The covalent linkage between metals via the sulfate group, forming infinite 1D zigzag chains, ensures the entanglement of the structure. These chains, in turn, are further assembled into a 2D network through N-H...O hydrogen bonding. Thermal analyses underline the high thermal stability of our com…
Catalysis Concepts in Medicinal Inorganic Chemistry
2018
Catalysis has strongly emerged in the field of medicinal inorganic chemistry as a suitable tool to deliver new drug candidates and to overcome drawbacks associated to metallodrugs. In this Concept article, we discuss representative examples of how catalysis has been applied in combination with metal complexes to deliver new therapy approaches. In particular, we explain key achievements in the design of catalytic metallodrugs that damage biomolecular targets and in the development of metal catalysis schemes for the activation of exogenous organic prodrugs. Moreover, we discuss our recent discoveries on the flavin-mediated bioorthogonal catalytic activation of metal-based prodrugs; a new cata…
Theoretical characterization of the photochemical reaction CO2+O(3P)→CO+O2 related to experiments in solid krypton
2020
Formation and decomposition of the complex of carbon dioxide and atomic oxygen are characterized by quantum chemistry methods aiming to rationalize experimental studies in solid krypton. The observed FTIR spectra reflected the temporal evolution of the system after irradiation showing the bands of reactants, intermediates and products. Advanced quantum chemistry calculations show that the T-shape complex CO2…O(3P) can be formed in the matrix. Its excitation by the 193 nm light results in the charge-transfer state CO2+…O-, which evolves to the reaction intermediate CO3. The latter species decomposes to CO + O2 following pathways on the excited state energy surfaces. peerReviewed