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  • A. Harbi, Y. L. Godec, Y. Li, H. Moutaabbid, S. Benmokhtar, et M. Moutaabbid, « Experimental and theoretical investigation of the electronic, magnetic, and optical properties of a new oxyphosphate, Ni0.25Mn0.25TiO(PO4) », Journal of Physics and Chemistry of Solids, vol. 148, p. 109633, 2021.
    Résumé : The structural, magnetic, and optical properties of a new oxyphosphate, Ni0.25Mn0.25TiOPO4, have been investigated by X-ray diffraction (XRD) analysis, magnetic FC-ZFC measurements, and vibrational spectroscopy (Raman, IR, WDS, and UV/visible). XRD analysis showed that the compound crystallizes in a monoclinic structure, space group P21/c, with unit cell parameters of a = 7.3758(2) Å, b = 7.3255(2) Å, c = 7.3448(2) Å, and β = 120.25(2)°. Elemental analysis of the powder confirmed the presence of Ni, Mn, Ti, and P therein. Raman and IR spectra show strong bands at 749 and 787 cm−1, respectively, attributable to the vibration of –Ti–O–Ti–O– bonds in infinite chains. Magnetic studies have been performed in the temperature range from 2 to 300 K. The results revealed a weak antiferromagnetic coupling between spins in Ni0.25Mn0.25TiOPO4. The band-gap energy was estimated as Eg = 1.99 eV based on UV/Vis spectrophotometry. To better understand the experimental data, density functional theory (DFT) computations were performed within the generalized gradient approximation (GGA) and GGA + U. The partial density of states (PDOS) shows strong hybridization between O 2p, Mn 3d, and Ni 3d in the valence band and between Mn 3d, Ni 3d, and Ti 3d in the conduction band.
    Mots-clés : ERMMES, POLE 2.


  • Abdmouleh, Fatma, El Arbi, Mehdi, Hajer, Ben Saad, Jellali, Karim, Etata, Emna, Amara, Ibtissem Ben, Pigeon, Pascal, Hanen, Ben Hassen, Top, Siden, Jaouen, Gérard, Hammami, Riadh, Mamdouh, Ben Ali, et Gupta, Girish Kumar, « Antimicrobial, Antitumor and Side Effects Assessment of a Newly Synthesized Tamoxifen Analog », Current Topics in Medicinal Chemistry, vol. 20, nᵒ 25, p. 2281-2288, mars 2020.
    Résumé : Background: Tamoxifen citrate is a very prevalent drug marketed under several trade names like Apo-Tamox, Nolvadex, Tamec, Tamizam, and Tamoplex. This molecule is approved by the FDA for breast cancer treatment. Some studies have shown that tamoxifen has anti-tuberculosis and antiparasitic activities. Like any drug, tamoxifen possesses side effects, more or less dangerous. Aims: Basically, this work is a comparative study that aims to: primarily compare the antimicrobial and antitumor activities of tamoxifen and a newly synthesized tamoxifen analog; and to determine the molecule with lesser side effects. Methods: Three groups of mice were injected with tamoxifen citrate and compound 2(1,1-bis[4-(3- dimethylaminopropoxy)phenyl]-2-phenyl-but-1-ene dihydrochloride) at doses corresponding to C1 (1/10), C2 (1/50), and C3 (1/100) to compound 2 lethal dose (LD50 = 75 mg/kg) administered to adult mice. A group of noninjected mice served as a study control. Results: Experimental results suggest that compound 2 has better antitumor and antimicrobial activity than tamoxifen citrate besides its lower toxicity effects. Conclusion: The results obtained from the present study confirmed the antitumor and antimicrobial effect of tamoxifen citrate and its hematological side effects. Compound 2 seems to be more effective than tamoxifen citrate for antitumor and antimicrobial treatment while having less hematological side effects and less disruption of the blood biochemical parameters. These findings encourage us to perform further studies on compound 2 and test it for other therapeutic uses for which tamoxifen was found effective.
    Mots-clés : CHEMBIO, POLE 3.

  • S. Alves, A. Paris, et E. Rathahao-Paris, « Mass spectrometry-based metabolomics for an in-depth questioning of human health », in Advances in Clinical Chemistry, Elsevier, 2020, p. S0065242320300214.

  • N. Audureau, F. Coumes, J. - M. Guigner, T. P. T. Nguyen, C. Ménager, F. Stoffelbach, et J. Rieger, « Thermoresponsive properties of poly(acrylamide-co-acrylonitrile)-based diblock copolymers synthesized (by PISA) in water », Polymer Chemistry, vol. 11, nᵒ 37, p. 5998-6008, sept. 2020.
    Résumé : In this present work, we report the synthesis of UCST-thermoresponsive diblock copolymers using reversible addition fragmentation chain transfer (RAFT) polymerization in aqueous media. A water-soluble poly(N,N-dimethylacrylamide) macromolecular chain transfer agent (PDMAc macroRAFT) is used to promote and control the copolymerization of acrylamide and acrylonitrile in water and obtain PDMAc-b-P(AAm-co-AN) diblock copolymers. The fAN,0 and the length of the thermosensitive block (DPn) are systematically varied, in order to study their influence on the thermoresponsiveness of the block copolymers. A good blocking efficiency is generally evidenced by size exclusion chromatography. Remarkably, amphiphilic copolymer nanoparticles are formed in situ for the highest fAN,0. This is indeed the first time that such particles are produced by a polymerization-induced self-assembly (PISA) process. The morphology of the in situ formed nanoparticles and their behavior with temperature are studied by means of dynamic light scattering (DLS), (cryogenic) transmission electron microscopy ((cryo-)TEM) and turbidimetry. Spherical and worm-like nanoparticles are formed which exhibit unexpected properties, such as an unprecedented heating-induced worm-to-sphere morphological transition in water.
    Mots-clés : POLE 4, POLYMERES.
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  • P. Bayat, D. Lesage, et R. B. Cole, « Tutorial: Ion activation in tandem Mass spectrometry using ultra-high resolition spectroscopy », Mass Spectrometry Reviews, p. mas.21623, févr. 2020.

  • L. Bedoin, S. Alves, et J. - F. Lambert, « Origins of Life and Molecular Information: Selectivity in Mineral Surface-Induced Prebiotic Amino Acid Polymerization », ACS Earth and Space Chemistry, p. acsearthspacechem.0c00183, sept. 2020.

  • A. Benchohra, C. Méthivier, J. Landoulsi, D. Kreher, et R. Lescouëzec, « Electrospray ionization: an efficient approach to deposit polymetallic molecular switches onto gold surfaces », Chemical Communications, vol. 56, nᵒ 48, p. 6587-6589, 2020.
    Résumé : Electrospray ionization (EI) deposition is proven efficient in obtaining monolayers of a polymetallic charge transfer complex on gold surfaces. , Electrospray ionization (EI) deposition is proven efficient in obtaining monolayers of a polymetallic charge transfer complex on gold surfaces. The molecule's integrity is monitored by using PM-IRRAS and XPS. This approach broadens the perspective of molecular magnetic switch deposition, which is currently dominated by the thermal evaporation of monometallic spin crossover (SCO) complexes.
    Mots-clés : ERMMES, POLE 2.

  • B. Bertrand, C. Botuha, J. Forté, H. Dossmann, et M. Salmain, « A bis-chelating (O^N^O)/(N^N) ligand for the synthesis of heterobimetallic Pt(II)/Re(I) complexes: tools for the optimization of a new class of Pt(II) anticancer agents. », Chemistry – A European Journal, vol. 26, nᵒ 56, p. 12846-12861, 2020.
    Résumé : The two independent (O^N^O) and (N^N) coordination sites of a newly synthesized bis 2-(hydroxyphenyl)-1,2,4-triazole platform have been exploited to prepare four monometallic neutral (O^N^O)Pt(II) complexes carrying DMSO, pyridine, triphenylphosphine or N-heterocyclic carbene (NHC) as fourth ligand. Then the second (N^N) coordination site was used to introduce an IR-active rhenium tricarbonyl entity, affording the four corresponding heterobimetallic neutral Pt(II)/Re(I) complexes as well as a cationic Pt(II)/Re(I) derivative. X-ray crystallographic studies showed that distortion of the organic platform occurred to accommodate the coordination geometry of both metal centers. No ligand exchange and no transchelation occurred upon incubation of the Pt(II) complexes in aqueous environment or in the presence of Fe(III), respectively. The ligand and the complexes antiproliferative activity was first screened on the triple negative breast cancer cell line MDA-MB-231. Then the IC 50 of the most active candidates was determined on a wider panel of human cancer cells (MDA-MB-231, MCF-7 and A2780) as well as on a non-tumorigenic cell line (MCF-10F). Low micromolar activities were reached for the complexes carrying a DMSO ligand, making them the first examples of highly active though hydrolytically stable Pt(II) complexes. Finally, the characteristic mid-IR signature of the Re(CO) 3 fragment in the Pt/Re heterobimetallic complexes was used to quantify their uptake in breast cancer cells.
    Mots-clés : cancer, CHEMBIO, CSOB, heterobimetallic, pincer, platinum, POLE 3, rhenium.
    Note Note
    <p>doi: 10.1002/chem.202001752</p>

  • B. Bertrand, G. Gontard, C. Botuha, et M. Salmain, « Pincer-based heterobimetallic Pt(II)/Ru(II), Pt(II)/Ir(III) and Pt(II)/Cu(I) complexes: synthesis and evaluation antiproliferative properties », Eur

    opean Journal of Inorganic Chemistry
    , vol. 2020, nᵒ 35, p. 3370-3377, sept. 2020.
    Résumé : Platinum pincer-based complexes [(O^N^O)Pt(L)] (L = DMSO, pyridine, triphenylphosphine or 1,3-dimethylbenzimidazol-2-ylidene) carrying an (N^N) coordination site were used as starting materials to synthesize a series of seven cationic heterobimetallic Pt(II)/Ru(II), Pt(II)/Ir(III) and Pt(II)/Cu(I) presenting a [( p- cymene)RuCl] + , a [(Cp*)IrCl] + (Cp* = ? 5 -pentamethylcyclopentadienyl) and a [(NHC iPr )Cu] + (NHC iPr = 1,3-bis(2,6-diisopropylphenyl)imidazole-2-ylidene) moiety respectively. The X-ray structure of one of the bimetallic Pt(II)/Ir(III) complexes showed a distortion of the organic platform to accommodate the coordination geometry of both metal centers as already observed for previous Pt(II)/Re(I) complexes. The antiproliferative activity of the complexes was first screened on the triple negative breast cancer cell line MDA-MB-231. Then the IC 50 of the most active candidates was determined on a wider panel of human cancer cells (MDA-MB-231, MCF-7 and A2780) as well as on a non-tumorigenic cell line (MCF-10A). The most toxic compound, namely the Pt(II)/Cu(I) heterobimetallic complex 4c showed an antiproliferative activity down to the nanomolar level.
    Mots-clés : Bioorganometallic chemistry, cancer, CHEMBIO, heterobimetallic complexes, platinum, POLE 3, Synthesis.
    Note Note
    <p>doi: 10.1002/ejic.202000717</p>

  • P. Biais, O. Colombani, L. Bouteiller, F. Stoffelbach, et J. Rieger, « Unravelling the formation of BAB block copolymer assemblies during PISA in water », Polymer Chemistry, vol. 11, nᵒ 28, p. 4568-4578, juill. 2020.
    Résumé : The mechanism of formation of associative BAB triblock copolymers through aqueous polymerization-induced self-assembly (PISA) is investigated for the first time, on copolymers constituted of a hydrophilic poly(N,N-dimethylacrylamide) block (PDMAc = block A) and a hydrophobic poly(diacetone acrylamide) block (PDAAm = block B). Such BAB copolymers tend to form bridged micelles/networks, which was expected to make the PISA process much more complex than for conventional diblock copolymers. Kinetic monitoring, light scattering analyses and macroscopic observations allowed identifying crucial parameters that influence the polymerization and the final dispersion properties, notably the stirring of the polymerization medium, the macroRAFT agent concentration, its ionization degree (related to the pH) and its Z group alkyl chain length.
    Mots-clés : POLE 4, POLYMERES.
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  • A. Cartier, E. Levernier, A. - L. Dhimane, T. Fukuyama, C. Ollivier, I. Ryu, et L. Fensterbank, « Synthesis of Aliphatic Amides through a Photoredox Catalyzed Radical Carbonylation Involving Organosilicates as Alkyl Radical Precursors », Advanced Synthesis & Catalysis, vol. 362, nᵒ 11, p. 2254-2259, 2020.
    Résumé : Alkyl radicals, from primary to tertiary, formed by photocatalyzed oxidation of organosilicates, are involved efficiently in radical carbonylation with carbon monoxide (CO), in the presence of various amines and CCl4, leading to a variety of amides in moderate to good yields.
    Mots-clés : Carbonylation, MACO, multi-component reaction, photooxidative catalysis, POLE 1, radical/polar, silicates.
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  • F. Coumes, M. Balarezo, J. Rieger, et F. Stoffelbach, « Biobased Amphiphilic Block Copolymers by RAFT-Mediated PISA in Green Solvent », Macromolecular Rapid Communications, vol. 41, nᵒ 9, p. 2000002, 2020.
    Résumé : Biobased amphiphilic diblock copolymers are prepared thanks to the combination of reversible addition–fragmentation transfer (RAFT) polymerization and polymerization-induced self-assembly (PISA) in an eco-friendly solvent mixture. First, the formation of a poly(acrylic acid) macroRAFT agent (PAA-TTC) is performed in water at 70 °C. Then, in a series of experiments, the PAA-TTC macroRAFT agent is used directly, without purification, as both chain transfer agent and stabilizing agent in the RAFT-PISA of menthyl acrylate (MnA) in dispersion in an ethanol/water mixture. The polymerizations of MnA are fast with high final conversions and well-controlled amphiphilic diblock copolymers are synthesized. Stable, sub-micrometric spherical particles composed of the diblock copolymers are formed. The influence of the monomer concentration and the length of the solvophobic block on the diameter of the self-assemblies is studied by means of dynamic light scattering and cryogenic transmission electron-microscopy.
    Mots-clés : amphiphilic copolymers, biobased monomers, dispersion polymerization, PISA, POLE 4, POLYMERES, RAFT.
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  • L. Cunningham, Y. Wang, C. Nottingham, J. Pagsulingan, G. Jaouen, M. McGlinchey, et P. J. Guiry, « Enantioselective Synthesis of Planar Chiral Ferrocifens that Show Chiral Discrimination in Antiproliferative Activity on Breast Cancer Cells », ChemBioChem, vol. n/a, nᵒ n/a, 2020.
    Résumé : The design and first enantioselective synthesis of a series of chiral ferrocifens and ferrociphenols was realised via enantioselective palladium-catalysed intramolecular direct C?H bond activation followed by McMurry coupling. Biological evaluation revealed moderate anticancer activities on breast cancer cells and evidence of chiral discrimination between enantiomers. Treatment of these novel ferrocifens with Ag 2 O revealed that these systems are unable to form a neutral quinone methide, yet still demonstrate marked antiproliferative properties versus both the hormone-dependent MCF-7 and hormone-independent MDA-MB-231 cell lines. This bioactivity arises from two mechanisms: Fenton-type chemistry and the anti-estrogenic activity associated with the tamoxifen-like structure.
    Mots-clés : anti-cancer activity, asymmetric synthesis, CHEMBIO, Ferrocene, McMurry coupling, POLE 3.
    Note Note
    <p>doi: 10.1002/cbic.202000311</p>

  • F. D'Agosto, J. Rieger, et M. Lansalot, « RAFT-Mediated Polymerization-Induced Self-Assembly », Angewandte Chemie International Edition, vol. 59, nᵒ 22, p. 8368-8392, 2020.
    Résumé : After a brief history that positions polymerization-induced self-assembly (PISA) in the field of polymer chemistry, this Review will cover the fundamentals of the PISA mechanism. Furthermore, this Review will also give an overview of some of the features and limitations of RAFT-mediated PISA in terms of the choice of the components involved, the nature of the nanoobjects that can be obtained and how the syntheses can be controlled, as well as some potential applications.
    Mots-clés : block copolymers, heterogeneous polymerization, morphology, PISA, POLE 4, POLYMERES, RAFT.
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  • A. Delvaux, E. Rathahao‐Paris, et S. Alves, « An emerging powerful technique for distinguishing isomers: Trapped Ion Mobility Spectrometry ‐ Time‐of‐Flight Mass Spectrometry for a rapid characterization of estrogen isomers », Rapid Communications in Mass Spectrometry, août 2020.

  • H. Dossmann, D. Gatineau, H. Clavier, A. Memboeuf, D. Lesage, et Y. Gimbert, « Exploring Phosphine Electronic Effects on Molybdenum Complexes: A Combined Photoelectron Spectroscopy and Energy Decomposition Analysis Study », The Journal of Physical Chemistry A, p. acs.jpca.0c06746, oct. 2020.

  • H. Du, F. A. de Oliveira, L. J. C. Albuquerque, G. Tresset, E. Pavlova, C. Huin, P. Guégan, et F. C. Giacomelli, « Polyglycidol-Stabilized Nanoparticles as a Promising Alternative to Nanoparticle PEGylation: Polymer Synthesis and Protein Fouling Considerations », Langmuir, vol. 36, nᵒ 5, p. 1266-1278, févr. 2020.
    Résumé : We herein demonstrate the outstanding protein-repelling characteristic of star-like micelles and polymersomes manufactured from amphiphilic block copolymers made by poly(butylene oxide) (PBO) hydrophobic segments and polyglycidol (PGL) hydrophilic outer shells. Although positively charged proteins (herein modeled by lysozyme) may adsorb onto the surface of micelles and polymersomes where the assemblies are stabilized by short PGL chains (degree of polymerization smaller than 15), the protein adsorption vanishes when the degree of polymerization of the hydrophilic segment (PGL) is higher than ∼20, regardless the morphology. This has been probed by using three different model proteins which are remarkably different concerning molecular weight, size, and zeta potential (bovine serum albumin (BSA), lysozyme, and immunoglobulin G (IgG)). Indeed, the adsorption of the most abundant plasma protein (herein modeled as BSA) is circumvented even by using very short PGL shells due to the highly negative zeta potential of the produced assemblies which presumably promote protein–nanoparticle electrostatic repulsion. The negative zeta potential, on the other hand, enables lysozyme adsorption, and the phenomenon is governed by electrostatic forces as evidenced by isothermal titration calorimetry. Nevertheless, the protein coating can be circumvented by slightly increasing the degree of polymerization of the hydrophilic segment. Notably, the PGL length required to circumvent protein fouling is significantly smaller than the one required for PEO. This feature and the safety concerns regarding the synthetic procedures on the preparation of poly(ethylene oxide)-based amphiphilic copolymers might make polyglycidol a promising alternative toward the production of nonfouling spherical particles.
    Mots-clés : POLE 4, POLYMERES.
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  • L. El Khoury, F. Célerse, L. Lagardère, L. - H. Jolly, E. Derat, Z. Hobaika, R. G. Maroun, P. Ren, S. Bouaziz, N. Gresh, et J. - P. Piquemal, « Reconciling NMR Structures of the HIV-1 Nucleocapsid Protein NCp7 Using Extensive Polarizable Force Field Free-Energy Simulations », Journal of Chemical Theory and Computation, vol. 16, nᵒ 4, p. 2013-2020, avr. 2020.
    Résumé : Using polarizable (AMOEBA) and nonpolarizable (CHARMM) force fields, we compare the relative free energy stability of two extreme conformations of the HIV-1 nucleocapsid protein NCp7 that had been previously experimentally advocated to prevail in solution. Using accelerated sampling techniques, we show that they differ in stability by no more than 0.75–1.9 kcal/mol depending on the reference protein sequence. While the extended form appears to be the most probable structure, both forms should thus coexist in water explaining the differing NMR findings.
    Mots-clés : MACO, POLE 1.
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  • R. El-Hnayn, L. Canabady-Rochelle, C. Desmarets, L. Balan, H. Rinnert, O. Joubert, G. Medjahdi, H. Ben Ouada, et R. Schneider, « One-Step Synthesis of Diamine-Functionalized Graphene Quantum Dots from Graphene Oxide and Their Chelating and Antioxidant Activities », Nanomaterials, vol. 10, nᵒ 1, p. 104, janv. 2020.
    Résumé : 2,2&rsquo;-(Ethylenedioxy)bis(ethylamine)-functionalized graphene quantum dots (GQDs) were prepared under mild conditions from graphene oxide (GO) via oxidative fragmentation. The as-prepared GQDs have an average diameter of ca. 4 nm, possess good colloidal stability, and emit strong green-yellow light with a photoluminescence (PL) quantum yield of 22% upon excitation at 375 nm. We also demonstrated that the GQDs exhibit high photostability and the PL intensity is poorly affected while tuning the pH from 1 to 8. Finally, GQDs can be used to chelate Fe(II) and Cu(II) cations, scavenge radicals, and reduce Fe(III) into Fe(II). These chelating and reducing properties that associate to the low cytotoxicity of GQDs show that these nanoparticles are of high interest as antioxidants for health applications.
    Mots-clés : 2, 2’-(ethylenedioxy)bis(ethylamine), ARC, graphene quantum dots, optical properties, POLE 1, redox-active nanoparticles.
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  • G. Falco, L. Simonin, S. Pensec, F. Dalmas, J. - M. Chenal, L. Bouteiller, et L. Chazeau, « Linear and nonlinear viscoelastic properties of segmented silicone-urea copolymers: Influence of the hard segment structure », Polymer, vol. 186, p. 122041, janv. 2020.
    Résumé : The linear and non-linear viscoelastic behaviors of 5 segmented silicone copolymers - with low fraction of 1,6-hexamethylene diisocyanate (HDI), 4,4′-methylenebis (cyclohexyl isocyanate) (HMDI), 1,3-bis(1-isocyanato-1-methylethyl)benzene (TMXDI), 2,4-tolylene diisocyanate (TDI) or isophorone diisocyanate (IPDI) as hard segments (HS) - are compared, in relation with their microstructure. When the HS are non-symmetrical, the materials nanostructuration is weak and has a limited impact on the mechanical response: two mechanical relaxations occur after the α relaxation of the polydimethylsiloxane (PDMS), the first related to the “unfreezing” of the HS-HS bonds, and the second one to the sticky reptation of the polymer chains. Conversely, when the HS are symmetrical, their self-organization is favored and the long range ordering of the HS is possible. The materials are then semi-crystalline like, with a low crystallinity (due to the low weight percentage of HS) and their flow, possible above their melting temperature (Tm), depends also on the HS dynamics, which is the most rapid for HDI.
    Mots-clés : Mechanical relaxations, Nanostructure, POLE 4, POLYMERES, Segmented copolymers.

  • F. Giusti, M. Casiraghi, E. Point, M. Damian, J. Rieger, C. L. Bon, A. Pozza, K. Moncoq, J. - L. Banères, et L. J. Catoire, « Structure of the agonist 12–HHT in its BLT2 receptor-bound state », Scientific Reports, vol. 10, nᵒ 1, p. 2630, févr. 2020.
    Résumé : G Protein-Coupled receptors represent the main communicating pathway for signals from the outside to the inside of most of eukaryotic cells. They define the largest family of integral membrane receptors at the surface of the cells and constitute the main target of the current drugs on the market. The low affinity leukotriene receptor BLT2 is a receptor involved in pro- and anti-inflammatory pathways and can be activated by various unsaturated fatty acid compounds. We present here the NMR structure of the agonist 12–HHT in its BLT2-bound state and a model of interaction of the ligand with the receptor based on a conformational homology modeling associated with docking simulations. Put into perspective with the data obtained with leukotriene B4, our results illuminate the ligand selectivity of BLT2 and may help define new molecules to modulate the activity of this receptor.
    Mots-clés : POLE 4, POLYMERES.
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  • J. Glatz, L. - M. Chamoreau, A. Flambard, J. - F. Meunier, A. Bousseksou, et R. Lescouëzec, « Thermo- and electro-switchable Cs⊂{Fe <sub>4</sub> –Fe <sub>4</sub> } cubic cage: spin-transition and electrochromism », Chemical Communications, vol. 56, nᵒ 74, p. 10950-10953, 2020.
    Résumé : The Cs⊂{Fe 4 –Fe 4 } cube is a dual redox and magnetic switch showing remarkable electrochromic properties and spin-transition in its neutral state. , A mixed valence Cs⊂{Fe 4 –Fe 4 } cyanido-cube was synthesized and structurally characterized. The molecule, which is robust in solution, shows remarkable electronic versatility. Electrochromic properties associated with nine different electronic states are observed in solution together with a thermo-induced spin-transition in the solid state.
    Mots-clés : ERMMES, POLE 2.

  • Y. T. L. Guen, T. L. Gall, P. Midoux, P. Guégan, S. Braun, et T. Montier, « Gene transfer to skeletal muscle using hydrodynamic limb vein injection: current applications, hurdles and possible optimizations », The Journal of Gene Medicine, vol. 22, nᵒ 2, p. e3150, 2020.
    Résumé : Hydrodynamic limb vein injection is an in vivo locoregional gene delivery method. It consists of administrating a large volume of solution containing nucleic acid constructs in a limb with both blood inflow and outflow temporarily blocked using a tourniquet. The fast, high pressure delivery allows the musculature of the whole limb to be reached. The skeletal muscle is a tissue of choice for a variety of gene transfer applications, including gene therapy for Duchenne muscular dystrophy or other myopathies, as well as for the production of antibodies or other proteins with broad therapeutic effects. Hydrodynamic limb vein delivery has been evaluated with success in a large range of animal models. It has also proven to be safe and well-tolerated in muscular dystrophy patients, thus supporting its translation to the clinic. However, some possible limitations may occur at different steps of the delivery process. Here, we have highlighted the interests, bottlenecks and potential improvements that could further optimize non-viral gene transfer following hydrodynamic limb vein injection.
    Mots-clés : gene transfer, hydrodynamic delivery, locoregional, non-viral gene delivery, optimizations, POLE 4, POLYMERES, skeletal muscle.
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    Note Note
    <p>e3150 JGM-19-0364.R1</p>

  • H. Guo, D. Hourdet, A. Marcellan, F. Stoffelbach, J. Lyskawa, L. de Smet, A. Vebr, R. Hoogenboom, et P. Woisel, « Dual Responsive Regulation of Host–Guest Complexation in Aqueous Media to Control Partial Release of the Host », Chemistry – A European Journal, vol. 26, nᵒ 6, p. 1292-1297, janv. 2020.
    Résumé : Abstract The regulation of the concentration of a wide range of small molecules is ubiquitous in biological systems because it enables them to adapt to the continuous changes in the environmental conditions. Herein, we report an aqueous synthetic system that provides an orchestrated, temperature and pH controlled regulation of the complexation between the cyclobis(paraquat-p-phenylene) host (BBox) and a 1,5-dialkyloxynaphthalene (DNP) guest attached to a well-defined dual responsive copolymer composed of N-isopropylacrylamide as thermoresponsive monomer and acrylic acid as pH-responsive monomer. Controlled, partial release of the BBox, enabling control over its concentration, is based on the tunable partial collapse of the copolymer. This colored supramolecular assembly is one of the first synthetic systems providing control over the concentration of a small molecule, providing great potential as both T and pH chromic materials and as a basis to develop more complex systems with molecular communication.
    Mots-clés : host–guest systems, molecular recognition, POLE 4, POLYMERES, polymers, supramolecular chemistry.

  • S. Han, G. Mellot, S. Pensec, J. Rieger, F. Stoffelbach, E. Nicol, O. Colombani, J. Jestin, et L. Bouteiller, « Crucial Role of the Spacer in Tuning the Length of Self-Assembled Nanorods », Macromolecules, vol. 53, nᵒ 1, p. 427-433, janv. 2020.
    Résumé : Polymeric supramolecular nanorods were prepared in toluene by self-assembly of tris(urea) stickers connected on both sides through alkyl spacers of different lengths to short polystyrene (PS) arms. Several tris(urea) initiators or chain transfer agents were synthesized straightforwardly and used to grow well-defined PS arms via atom transfer radical polymerization (ATRP) or reversible addition fragmentation chain transfer (RAFT) polymerization. Self-assembly was investigated by means of Fourier-transform infrared (FTIR) spectroscopy and light/neutron scattering. A dramatic impact of the spacer separating the tris(urea) sticker from the PS arms on the extent of self-assembly was observed in toluene as long as the degree of polymerization of the PS arms (x) was kept short (x ∼ 10). Indeed, supramolecular nanorods several hundreds of nanometers in length for a few nanometers in radius were obtained with a spacer consisting of nine atoms, whereas five times shorter nanorods were obtained for a spacer of only five atoms, and spherical particles were found in the absence of any spacer, all other parameters remaining unchanged. These results reveal the possibility to tune the length of polymer-decorated supramolecular nanorods with minimal modification of the assembling sticker and without affecting the functionality of the rods.
    Mots-clés : POLE 4, POLYMERES.
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  • J. A. Hawkes, J. D'Andrilli, J. N. Agar, M. P. Barrow, S. M. Berg, N. Catalán, H. Chen, R. K. Chu, R. B. Cole, T. Dittmar, R. Gavard, G. Gleixner, P. G. Hatcher, C. He, N. J. Hess, R. H. S. Hutchins, A. Ijaz, H. E. Jones, W. Kew, M. Khaksari, D. C. Palacio Lozano, J. Lv, L. R. Mazzoleni, B. E. Noriega‐Ortega, H. Osterholz, N. Radoman, C. K. Remucal, N. D. Schmitt, S. K. Schum, Q. Shi, C. Simon, G. Singer, R. L. Sleighter, A. Stubbins, M. J. Thomas, N. Tolic, S. Zhang, P. Zito, et D. C. Podgorski, « An international laboratory comparison of dissolved organic matter composition by high resolution mass spectrometry: Are we getting the same answer? », Limnology and Oceanography: Methods, vol. 18, nᵒ 6, p. 235-258, 2020.

  • D. Jamroz, N. Fischer-Durand, M. Palusiak, S. Wojtulewski, S. Jarzyński, M. Stępniewska, M. Salmain, et B. Rudolf, « Inverse electron-demand Diels-Alder (iEDDA) bioorthogonal conjugation of half-sandwich transition metallocarbonyl entities to a model protein », Applied Organometallic Chemistry, vol. 34, nᵒ 4, p. e5507, 2020.
    Résumé : Novel transition metallocarbonyl complexes carrying a norbornene or an oxanorbornene group were synthesized by [4 + 2] cycloaddition between the organometallic maleimide dienophiles and cyclopentadiene or furan, respectively. The oxanorbornene adduct was obtained as a mixture of endo and exo isomers as confirmed by X-ray diffraction and NMR spectroscopy. The (oxa)norbornene groups further provided convenient chemical reporters to carry out inverse electron demand Diels-Alder (iEDDA) reactions with tetrazine derivatives. Detailed kinetic studies with a model tetrazine revealed that faster rates of reaction were determined with both isomers of the oxanorbornene complex with respect to the norbornene complexes. Eventually, incorporation of metallocarbonyl entities into bovine serum albumin equipped with tetrazine handles was achieved as shown by IR spectroscopy of the protein conjugates.
    Mots-clés : bioconjugation, CHEMBIO, iEDDA, metallocarbonyl complex, norbornene, POLE 3, tetrazine.
    Note Note
    <p>doi: 10.1002/aoc.5507</p>

  • J. ‐R. Jiménez, J. Glatz, A. Benchohra, G. Gontard, L. ‐M. Chamoreau, J. ‐F. Meunier, A. Bousseksou, et R. Lescouëzec, « Electron Transfer in the Cs⊂{Mn <sub>4</sub> Fe <sub>4</sub> } Cubic Switch: A Soluble Molecular Model of the MnFe Prussian‐Blue Analogues », Angewandte Chemie International Edition, vol. 59, nᵒ 21, p. 8089-8093, mai 2020.

  • E. Levernier, C. Lévêque, E. Derat, L. Fensterbank, et C. Ollivier, « Towards Visible-Light Photocatalytic Reduction of Hypercoordinated Silicon Species », Helvetica Chimica Acta, vol. 103, nᵒ 1, p. e1900238, 2020.
    Résumé : Nowadays, the quest of new radical precursors based on heteroatom complexes occupies an increasingly prominent position in contemporary research. Herein, we investigated the behavior and the limitations of hexa- or pentacoordinated organochlorosilanes and related pentacoordinated silyliums as new families of complexes for the generation of radicals under photocatalytic reductive conditions. Particularly, treatment of chlorophenylbis[N,S-pyridine-2-thiolato(−)]silicon(IV) or the related silylium derivative with the fac-Ir(ppy)3 (5 mol-%)/NEt3 (1.5 equiv.) system under blue LEDs irradiation generates a thiopyridyl radical which can participate in the formation of a carbon−sulfur bond by reaction with an allylsulfone. Computational studies supported this experimental finding, and particularly by showing that homolytic fragmentation of C−Ts bond is favored over the fragmentation of thiopyridyl radical.
    Mots-clés : allylation, chlorosilane, cyclic voltammetry, C−S bond, hypercoordinated silicon compounds, MACO, photoreduction, POLE 1, radicals, silylium.
    Pièce jointe Full Text PDF 8.3 Mo (source)

  • A. Li, Y. Li, L. - M. Chamoreau, C. Desmarets, L. Lisnard, et Y. Journaux, « A Bis-Polydentate Oxamate-Based Achiral Ligand That Can Stabilize a Macrocyclic Mixed Valence Compound or Induce a 1D Helical Chain », European Journal of Inorganic Chemistry, vol. 2020, nᵒ 34, p. 3311-3319, 2020.
    Résumé : The reaction of the N-(2-hydroxyphenyl)oxamate ligand (ohpma) has been investigated with cobalt(II) and copper(II) ions. It has led to two coordination compounds, (TMA)3[CoIII(ohpma)2CoII(MeOH)23]·10H2O·5MeOH (1) and (HNEt3)[Cu(ohpma)] (2). Both compounds have been characterized by single-crystal X-ray diffraction and magnetometry. The X-ray diffraction studies have revealed atypical structures that are not commonly observed in oxamate coordination chemistry with a macrocyclic arrangement for the mixed-valence cobalt-based complex 1, and a helical chiral chain for compound 2. In the latter, the bis-polydentate nature of the (ohpma)3– ligand with distinct tridentate and bidentate coordination sites creates a chirogenic center on the copper ion. The investigation of the magnetic properties shows for complex 1 a single-molecule magnet behavior detectable under static field, while antiferromagnetic interactions dominate the behavior of 2.
    Mots-clés : ARC, ERMMES, POLE 1, POLE 2.

  • Y. Li, A. Hammoud, L. Bouteiller, et M. Raynal, « Emergence of Homochiral Benzene-1,3,5-tricarboxamide Helical Assemblies and Catalysts upon Addition of an Achiral Monomer », Journal of the American Chemical Society, vol. 142, nᵒ 12, p. 5676-5688, mars 2020.
    Résumé : Chirality amplification refers to the ability of a small chiral bias to fully control the main chain helicity of polymers and assemblies. Further implementation of functional chirally amplified helices as switchable asymmetric catalysts, chiral sensors, and circularly polarized light emitters will require a greater control of the energetics governing these chirality amplification effects. In this work, we report on the counterintuitive ability of an achiral molecule to suppress conformational defects in supramolecular helices, thus leading to the emergence of homochirality in a system containing a very small chiral bias. We focus our investigation on supramolecular helices composed of an achiral benzene-1,3,5-tricarboxamide (BTA) ligand, coordinated to copper, and an enantiopure BTA comonomer. Amplification of chirality as probed by varying the amount (sergeants and soldiers effect) or the optical purity (diluted majority-rules effect) of the enantiopure comonomer are modest in this initial system. However, both effects are hugely enhanced upon addition of a second achiral BTA monomer, leading to a perfect control of the helicity either by means of a remarkably low amount of sergeants (0.5%) or a small bias from a racemic mixture of enantiopure comonomers (10% ee). Such an enhancement in the amplification of chirality is only achieved by mixing the three components, i.e. the two achiral and the enantiopure comonomers, highlighting a synergistic effect upon coassembly of the three monomers. Investigation of the role of the achiral additive by multifarious analytical techniques supports its ability to stabilize the helical coassemblies and suppress helix reversals: i.e., conformational defects. Implementation of these helical copper precatalysts in the hydrosilylation of 1-(4-nitrophenyl)ethanone confirms that the effect of the achiral BTA additive is also operative under the conditions of the catalytic experiment. A highly enantioenriched product (90% ee) is produced by a supramolecular catalyst operating with ppm levels of chiral species.
    Mots-clés : POLE 4, POLYMERES.
    Pièce jointe Full Text PDF 5.5 Mo (source)

  • Z. Li, T. Bavaro, S. Tengattini, R. Bernardini, M. Mattei, F. Annunziata, R. B. Cole, C. Zheng, M. Sollogoub, L. Tamborini, M. Terreni, et Y. Zhang, « Chemoenzymatic synthesis of arabinomannan (AM) glycoconjugates as potential vaccines for tuberculosis », European Journal of Medicinal Chemistry, vol. 204, p. 112578, 2020.
    Mots-clés : CSOB, GOBS, POLE 3.

  • X. Liu, X. Su, C. Livache, L. - M. Chamoreau, S. Sanaur, L. Sosa-Vargas, J. - C. Ribierre, D. Kreher, E. Lhuillier, E. Lacaze, et F. Mathevet, « Investigation of charge transport properties of [1]Benzothieno[3,2-b][1]-benzothiophene single-crystals in field-effect transistor configuration », Organic Electronics, vol. 78, p. 105605, mars 2020.
    Résumé : Single-crystals of unsubstituted [1]Benzothieno[3,2-b][1]-benzothiophene (BTBT) were prepared by physical vapor transport deposition (VTP). The packing structure and morphology of the crystals were studied by X-ray diffraction (XRD), polarized optical microscopy (POM), scanning electron microscopy (SEM) and atomic force microscopy (AFM). The charge transport properties of BTBT single-crystals were also investigated via bottom contact/bottom gate (BC/BG) organic field-effect transistors (OFETs) on both SiO2 and n-octadecyltrichlorosilane (OTS) treated surfaces. A maximum hole mobility value of 0.032 cm2V−1s−1 was measured on the OTS substrate. In addition, single-crystal OFETs with ion gel top gate (TG) configuration were also investigated for low voltage operation. This work represents the first investigation of charge carrier mobility of a simple BTBT in transistor configuration and highlights the essential role of the BTBT substitution in charge transport properties.
    Mots-clés : Organic field effect transistors, POLE 4, POLYMERES, Semiconducting materials, Single crystals, Thienoacene derivative.

  • Y. Liu, J. Oble, A. Pradal, et G. Poli, « Catalytic Domino Annulations through η <sup>3</sup> -Allylpalladium Chemistry: A Never-Ending Story: Catalytic Domino Annulations through η <sup>3</sup> -Allylpalladium Chemistry: A Never-Ending Story », European Journal of Inorganic Chemistry, vol. 2020, nᵒ 11-12, p. 942-961, mars 2020.

  • Y. Liu, J. Oble, A. Pradal, et G. Poli, « Catalytic Domino Annulations through η3-Allylpalladium Chemistry: A Never-Ending Story », European Journal of Inorganic Chemistry, vol. 2020, nᵒ 11-12, p. 942-961, 2020.
    Résumé : Annulative η3-allylpalladium chemistry has been a longstanding trending research topic since the 80's. Nowadays, this research area is still providing challenges to the catalysis community leading to the development original and brand-new transformations. Several reaction partners have been used as precursors for η3-allylpalladium species, namely allyl diacetates, allyl monoacetates, 3-acetoxy-2-trimethylsilylmethyl-1-propene (ASMP), alkylidene cyclopropanes (ACPs), vinyl cyclopropanes (VCPs), vinyl aziridines, and vinyl epoxides. This minireview is intended to show the recent developments in the field of annulative η3-allylpalladium chemistry with emphasis on new reactivity, enantioselective transformations as well as potential applications in total synthesis.
    Mots-clés : POLE 1, ROCS.

  • T. Martinez, I. Alahyen, G. Lemière, V. Mouriès-Mansuy, et L. Fensterbank, « Straightforward Access to 2-Iodoindolizines via Iodine-Mediated Cyclization of 2-Pyridylallenes », Organic Process Research & Development, vol. 24, nᵒ 5, p. 817-821, mai 2020.
    Résumé : A metal-free access to 2-iodo-1,3-disubstituted indolizines has been developed. The proposed synthesis is relatively simple and efficient and involves the iodine-triggered 5-endo-trig cyclization of 2-pyridylallene precursors. While it can be conducted on a gram scale, the preparation of the precursors is straightforward and does not always require intermediate purifications. The obtained 2-iodoindolizines can be further functionalized through cross-coupling reactions.
    Mots-clés : MACO, POLE 1.
    Pièce jointe Full Text PDF 848 ko (source)

  • F. Nolay, E. Sevin, M. Létévé, A. Bil, F. Gosselet, K. El Kirat, F. Djedaini-Pilard, S. Morandat, L. Fenart, C. Przybylski, et V. Bonnet, « First step to the improvement of the blood brain barrier passage of atazanavir encapsulated in sustainable bioorganic vesicles », International Journal of Pharmaceutics, vol. 587, p. 119604, 2020.

  • Š. Nováková Lachmanová, L. Pospíšil, J. Šebera, B. Talbi, M. Salmain, et M. Hromadová, « Electrochemical characterization of the artificial metalloenzyme papain-[(η6-arene)Ru(1,10-phenanthroline)Cl]+ », Journal of Electroanalytical Chemistry, vol. 859, p. 113882, 2020.
    Résumé : Electrochemical properties were studied for [(η6-arene)Ru(1,10-phenanthroline)Cl]Cl (arene = C6H5(CH2)2NHCOCH2Cl) organometallic complex 1, protein Papain PAP and its conjugate with organometallic complex 1-PAP. The latter can serve as an artificial metalloenzyme with catalytic activity in transfer hydrogenation. This work demonstrates that AC voltammetry and electrochemical impedance spectroscopy can be used as fast tools to screen the catalytic ability of 1-PAP electrochemically by studies of the catalytic hydrogen evolution reaction (HER). Proteins are known to catalyze this process, but we have shown that additional HER signal associated with the catalytic activity of 1 is observed for its conjugate with Papain 1-PAP.
    Mots-clés : Artificial metalloenzyme, CHEMBIO, Electrochemical admittance and impedance techniques, Papain, POLE 3, Ruthenium(II) complexes.

  • L. Plet, G. Delecourt, M. Hanafi, N. Pantoustier, G. Pembouong, P. Midoux, V. Bennevault, et P. Guégan, « Controlled star poly(2-oxazoline)s: Synthesis, characterization », European Polymer Journal, vol. 122, p. 109323, janv. 2020.
    Résumé : Poly(2-methyl-2-oxazoline) and poly(2-ethyl-2-oxazoline) star polymers with 3, 4 and 6 arms are synthesized from pluritriflate initiators. Characterization of the topology was achieved by NMR, SEC and kinetic studies. The initiation step of 2-ethyl-2-oxazoline being slow, heterogeneous star polymers in arm molar masses are obtained for low molar mass polymers. However, for both monomers, high molar mass homogeneous star polymers are obtained. A fast initiation is observed for the polymerization of 2-methyl-2-oxazoline, providing a control of the topology even at low molar mass. In the studied molar mass range, linear kinetic first order plots and linear molar mass as a function of conversion are obtained for both monomers, suggesting living polymerizations.
    Mots-clés : 2oxazoline polymerization, Pluritriflate initiators, POLE 4, POLYMERES, Star polymers.

  • V. Puchelle, H. Du, N. Illy, et P. Guégan, « Polymerization of epoxide monomers promoted by tBuP4 phosphazene base: a comparative study of kinetic behavior », Polymer Chemistry, vol. 11, nᵒ 21, p. 3585-3592, juin 2020.
    Résumé : The kinetics of the anionic ring-opening polymerizations (AROP) of epoxide monomers, 1,2-epoxybutane (BO), 1,2-epoxypropane (PO), tert-butyl glycidyl ether (tBuGE), allyl glycidyl ether (AGE), benzyl glycidyl ether (BnGE), and ethoxyethyl glycidyl ether (EEGE), was investigated using benzyl alcohol/tBuP4 as the initiating system. All the polymerizations proceed in a controlled manner following a first order kinetics with respect to the monomer. The influence of the side chains borne by the oxirane ring was evidenced. Propagating centers derived from epoxide bearing heretoatom-containing side chains display higher reactivities and propagation rates. A reactivity scale has been established and is as follows, kp,BnGE > kp,AGE > kp,EEGE ≫ kp,tBuGE ≈ kp,PO > kp,BO. Using BO as the model monomer and different initiator concentrations, the nature of the propagating species has been identified as ion pairs. The influence of a Lewis acid addition on the monomer reactivities and on the control of the polymerization was also investigated. In the presence of triisobutylaluminum (iBu3Al), polymerization kinetics was faster but led to a broadening of the molar mass distributions. The monomer reactivity scale was also strongly modified with kp,PO > kp,BO > kp,EEGE ≈ kp,AGE > kp,BnGE ≈ kp,tBuGE. The polymerizations of PO, BO and tBuGE follow zero order kinetics which is not the case for the other oxirane monomers.
    Mots-clés : pole 4, POLYMERES.
    Pièce jointe Full Text PDF 923.5 ko (source)

  • C. Qin, T. Matsushima, W. J. Potscavage, A. S. D. Sandanayaka, M. R. Leyden, F. Bencheikh, K. Goushi, F. Mathevet, B. Heinrich, G. Yumoto, Y. Kanemitsu, et C. Adachi, « Triplet management for efficient perovskite light-emitting diodes », Nature Photonics, vol. 14, nᵒ 2, p. 70-75, févr. 2020.
    Résumé : Perovskite light-emitting diodes are promising for next-generation lighting and displays because of their high colour purity and performance1. Although the management of singlet and triplet excitons is fundamental to the design of efficient organic light-emitting diodes, the nature of how excitons affect performance is still not clear in perovskite2–4 and quasi-two-dimensional (2D) perovskite-based devices5–9. Here, we show that triplet excitons are key to efficient emission in green quasi-2D perovskite devices and that quenching of triplets by the organic cation is a major loss path. Employing an organic cation with a high triplet energy level (phenylethylammonium) in a quasi-2D perovskite based on formamidinium lead bromide yields efficient harvesting of triplets. Furthermore, we show that upconversion of triplets to singlets can occur, making 100% harvesting of electrically generated excitons potentially possible. The external quantum and current efficiencies of our green (527 nm) devices reached 12.4% and 52.1 cd A−1, respectively.
    Mots-clés : POLE 4, POLYMERES.

  • J. P. Rada, J. Forté, G. Gontard, V. Corcé, M. Salmain, et N. A. Rey, « Isoxazole-Derived Aroylhydrazones and Their Dinuclear Copper(II) Complexes Show Antiproliferative Activity on Breast Cancer Cells with a Potentially Alternative Mechanism Of Action », ChemBioChem, vol. 21, nᵒ 17, p. 2474-2486, 2020.
    Résumé : Abstract This paper reports the design, synthesis and cytotoxicity studies of two new isoxazole-derived aroylhydrazone ligands and their dinuclear copper(II) complexes. Compounds were fully characterized by various spectroscopic and analytical techniques. The molecular structures of four derivatives were confirmed by X-ray crystallography. The stability of the ligands and the complexes in aqueous medium was monitored spectroscopically. Both the ligands and the complexes were shown to interact with calf thymus DNA (ct-DNA). Additionally, structures containing a phenol pendant arm were significantly more cytotoxic than those carrying a pendant pyridine substituent, reaching sub-micromolar IC50 values on the triple-negative human breast cancer cell line MDA-MB-231. The metal chelation and transchelation ability of the compounds towards FeII, FeIII and ZnII ions was explored as a possible mechanism of action of these compounds.
    Mots-clés : antitumor agents, aroylhydrazonic ligands, CHEMBIO, copper(II) complexes, cytotoxicity, DNA, POLE 3.
    Note Note
    <p>doi: 10.1002/cbic.202000122</p>

  • B. Rasolonjatovo, N. Illy, V. Bennevault, J. Mathé, P. Midoux, T. L. Gall, T. Haudebourg, T. Montier, P. Lehn, B. Pitard, H. Cheradame, C. Huin, et P. Guégan, « Temperature-Sensitive Amphiphilic Non-Ionic Triblock Copolymers for Enhanced In Vivo Skeletal Muscle Transfection », Macromolecular Bioscience, vol. 20, nᵒ 3, p. 1900276, 2020.
    Résumé : It is reported that low concentration of amphiphilic triblock copolymers of pMeOx-b-pTHF-b-pMeOx structure (TBCPs) improves gene expression in skeletal muscle upon intramuscular co-injection with plasmid DNA. Physicochemical studies carried out to understand the involved mechanism show that a phase transition of TBCPs under their unimer state is induced when the temperature is elevated from 25 to 37 °C, the body temperature. Several lines of evidences suggest that TBCP insertion in a lipid bilayer causes enough lipid bilayer destabilization and even pore formation, a phenomenon heightened during the phase transition of TBCPs. Interestingly, this property allows DNA translocation across the lipid bilayer model. Overall, the results indicate that TBCPs exhibiting a phase transition at the body temperature is promising to favor in vivo pDNA translocation in skeletal muscle cells for gene therapy applications.
    Mots-clés : amphiphilic copolymers, in vivo transfection, LCST, POLE 4, poly(2-methyl-2-oxazoline), POLYMERES, skeletal muscle.
    Pièce jointe Full Text PDF 1.3 Mo (source)

  • Y. Ren, J. Forte, K. Cheaib, N. Vanthuyne, L. Fensterbank, H. Vezin, M. Orio, S. Blanchard, et M. Desage-El Murr, « Optimizing Group Transfer Catalysis by Copper Complex with Redox-Active Ligand in an Entatic State », Iscience, vol. 23, nᵒ 3, p. UNSP 100955, mars 2020.
    Résumé : Metalloenzymes use earth-abundant non-noble metals to perform high-fidelity transformations in the biological world. To ensure chemical efficiency, metalloenzymes have acquired evolutionary reactivity-enhancing tools. Among these, the entatic state model states that a strongly distorted geometry induced by ligands around a metal center gives rise to an energized structure called entatic state, strongly improving the reactivity. However, the original definition refers both to the transfer of electrons or chemical groups, whereas the chemical application of this concept in synthetic systems has mostly focused on electron transfer, therefore eluding chemical transformations. Here we report that a highly strained redox-active ligand enables a copper complex to perform catalytic nitrogen- and carbon-group transfer in as fast as 2 min, thus exhibiting a strong increase in reactivity compared with its unstrained analogue. This report combines two reactivity-enhancing features from metalloenzymes, entasis and redox cofactors, applied to group-transfer catalysis.
    Mots-clés : aziridination, cu, E-POM, galactose-oxidas

    e, generation, MACO, metal-complexes, models, oxidation, POLE 1, POLE 2, radicals, reactivity, site.
    Pièce jointe Texte intégral 19.8 Mo (source)

  • M. Roy, V. Berezhnaia, M. Villa, N. Vanthuyne, M. Giorgi, J. - V. Naubron, S. Poyer, V. Monnier, L. Charles, Y. Carissan, D. Hagebaum‐Reignier, J. Rodriguez, M. Gingras, et Y. Coquerel, « Stereoselective Syntheses, Structures, and Properties of Extremely Distorted Chiral Nanographenes Embedding Hextuple Helicenes », Angewandte Chemie International Edition, vol. 59, nᵒ 8, p. 3264-3271, 2020.
    Résumé : We report a molecular design and concept using π-system elongation and steric effects from helicenes surrounding a triphenylene core toward stable chiral polycyclic aromatic hydrocarbons (PAHs) with a maximal π-distortion to tackle their aromaticity, supramolecular and molecular properties. The selective syntheses, and the structural, conformational and chiroptical properties of two diastereomeric large multi-helicenes of formula C90H48 having a triphenylene core and embedding three [5]helicene units on their inner edges and three [7]helicene units at their periphery are reported based on diastereoselective and, when applicable, enantiospecific Yamamoto-type cyclotrimerizations of racemic or enantiopure 9,10-dibromo[7]helicene. Both molecules have an extremely distorted triphenylene core, and one of them exhibits the largest torsion angle recorded so far for a benzene ring (twist=36.9°).
    Mots-clés : aromaticity, helicenes, POLE 1, polycyclic aromatic hydrocarbons, ROCS, stereoselectivity, strained molecules.

  • R. Salles, B. Abécassis, E. Derat, D. Brouri, A. Bernard, Q. Zhang, A. Proust, C. Desmarets, et G. Izzet, « Hierarchical Self-Assembly of Polyoxometalate-Based Organo Palladium(II) Metallomacrocycles via Electrostatic Interactions », Inorganic Chemistry, vol. 59, nᵒ 4, p. 2458-2463, févr. 2020.
    Résumé : The design and synthesis of a supramolecular square composed of polyoxometalate-based hybrid donors and ethylenediamine palladium(II) nodes are reported. The structure of the metallomacrocycle scaffold was inferred by diffusion NMR, small-angle X-ray scattering (SAXS), and molecular modeling. The metallomacrocycle scaffold that contains negatively and positively charged subunits can further self-assemble owing to a competition between the solvation energy of the discrete species and intermolecular electrostatic interactions. When the dissociating character of the solvent was lowered or when in the presence of a protic solvent, different types of multiscale organizations (vesicles and pseudo-1D structures) were selectively formed and were characterized by SAXS and transmission electron microscopy.
    Mots-clés : ARC, E-POM, MACO, POLE 1, POLE 2.
    Pièce jointe Full Text PDF 2.1 Mo (source)

  • M. Salmain, N. Fischer-Durand, et B. Rudolf, « Bioorthogonal Conjugation of Transition Organometallic Complexes to Peptides and Proteins: Strategies and Applications », European Journal of Inorganic Chemistry, vol. 2020, nᵒ 1, p. 21-25, 2020.
    Résumé : The advent of bioorthogonal chemistry has revolutionized the common practices in protein bioconjugation and contributed to a large extent to the development of chemical biology, a discipline aimed at studying biological/biochemical processes/events in their natural setting (living cells, whole organisms) using dedicated chemical tools. This minireview intends to provide an up-to-date overview on the various bioorthogonal strategies implemented for the conjugation of transition organometallic entities to peptides, peptide nucleic acids and proteins with a focus on targeted applications, i.e. fluorescence- or radio-labeling for imaging, controlled delivery of therapeutic agents and bioanalysis.
    Mots-clés : CHEMBIO, Click chemistry, Cycloaddition, Ferrocene, Manganese, Peptide nucleic acids, POLE 3.
    Note Note
    <p>doi: 10.1002/ejic.201900810</p>
    Note Note
    <p>doi: 10.1002/ejic.201900810</p>

  • Y. Shi, Y. Li, et T. Coradin, « Magnetically-oriented type I collagen-SiO2@Fe3O4 rods composite hydrogels tuning skin cell growth », Colloids and Surfaces B: Biointerfaces, vol. 185, p. 110597, 2020.

  • Y. Si, C. Grazon, G. Clavier, J. Rieger, Y. Tian, J. - F. Audibert, B. Sclavi, et R. Méallet-Renault, « Fluorescent Copolymers for Bacterial Bioimaging and Viability Detection », ACS Sensors, vol. 5, nᵒ 9, p. 2843-2851, sept. 2020.
    Résumé : Novel fluorescent labels with high photostability and high biocompatibility are required for microbiological imaging and detection. Here, we present a green fluorescent polymer chain (GFPC), designed to be nontoxic and water-soluble, for multicolor bioimaging and real-time bacterial viability determination. The copolymer is synthesized using a straightforward one-pot reversible addition–fragmentation chain-transfer (RAFT) polymerization technique. We show that GFPC does not influence bacterial growth and is stable for several hours in a complex growth medium and in the presence of bacteria. GFPC allows the labeling of the bacterial cytoplasm for multicolor bacterial bioimaging applications. It can be used in combination with propidium iodide (PI) to develop a rapid and reliable protocol to distinguish and quantify, in real time, by flow cytometry, live and dead bacteria.
    Mots-clés : POLE 4, POLYMERES.
    Pièce jointe Full Text PDF 2.9 Mo (source)

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