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2012



  • D. Rajwar, X. Sun, S. J. Cho, A. C. Grimsdale, et D. Fichou, « Synthesis and 2D self-assembly at the liquid-solid interface of end-substituted star-shaped oligophenylenes », CrystEngComm, vol. 14, nᵒ 16, p. 5182-5187, juill. 2012.
    Résumé : We report here on the synthesis and self-assembly of four star-shaped trigonal 1,3,5-tris-(1,1-biphenyl-4-yl)-benzene (TBB) derivatives substituted by different functional groups on the terminal positions of the three arms of the molecule: COOCH3 (1), COOH (2), NH2 (3), and CN (4). Self-assembly of the tries
    Mots-clés : FICHOU, NASCO, NSCO, POLE 2.

  • N. S. Rannulu et R. B. Cole, « Novel Fragmentation Pathways of Anionic Adducts of Steroids Formed by Electrospray Anion Attachment Involving Regioselective Attachment, Regiospecific Decompositions, Charge-Induced Pathways, and Ion-Dipole Complex Intermediates », Journal of the American Society for Mass Spectrometry, vol. 23, nᵒ 9, p. 1558-1568, sept. 2012.
    Résumé : The analysis of several bifunctional neutral steroids, 5-alpha-pregnane diol (5-alpha-pregnane-3 alpha-20 beta diol), estradiol (3,17 alpha-dihydroxy-1,3,5(10)-estratriene), progesterone (4-pregnene-3,20-dione), lupeol (3 beta-hydroxy-20(29)-lupene), pregnenolone (5-pregnen-3 beta-ol-20-one), and pregnenolone acetate (5-pregnen-3 beta-ol-20-one acetate) was accomplished by negative ion electrospray mass spectrometry (ESI-MS) employing adduct formation with various anions: fluoride, bicarbonate, acetate, and chloride. Fluoride yielded higher abundances of anionic adducts and more substantial abundances of deprotonated molecules compared with other investigated anions. Collision-induced dissociation (CID) of precursor [M+anion](-) adducts of these steroids revealed that fluoride adduct [M+F](-) precursors first lose HF to produce [M-H](-) and then undergo consecutive decompositions to yield higher abundances of structurally-informative product ions than the other tested anions. In addition to charge-remote fragmentations, the majority of CID pathways of estradiol are deduced to occur via charge-induced fragmentation. Most interestingly, certain anions exhibit preferential attachment to a specific site on these bifunctional steroid molecules, which we are calling "regioselective anion attachment." Regioselective anion attachment is evidenced by subsequent regiospecific decomposition. Regioselective attachment of fluoride (and acetate) anions to low (and moderate) acidity functional groups of pregnenolone, respectively, is demonstrated using deuterated compounds. Moreover, the formation of unique intermediate ion-dipole complexes leading to novel fragmentation pathways of fluoride adducts of pregnenolone acetate, and bicarbonate adducts of d(4)-pregnenolone, are also discussed.
    Mots-clés : anabolic-steroids, Anion attachment, assisted laser desorption/ionisation, atmospheric-pressure photoionization, Charge-induced decomposition, collision-induced dissociation, CSOB, Electrospray, endocrine disrupting compounds, gas-phase, Ion-dipole complex, Ion-neutral complex, liquid-chromatography, mass spectrometry, POLE 3, post-source decay, Regioselective, Regiospecific, solid-phase extraction, steroids, tandem mass-spectrometry.


  • J. Rieger, T. Antoun, S. - H. Lee, M. Chenal, G. Pembouong, J. Lesage de la Haye, I. Azcarate, B. Hasenknopf, et E. Lacôte, « Synthesis and Characterization of a Thermoresponsive Polyoxometalate–Polymer Hybrid », Chemistry – A European Journal, vol. 18, nᵒ 11, p. 3355–3361, 2012.
    Résumé : We report the synthesis of the first organo-POM with thermoresponsive properties. Our concept will provide chemists with a new tool to design POMs whose solubility is reversibly controllable through an external stimulus. POM–polymer TBA7[POM]-poly(N,N-diethylacrylamide) (POM–PDEAAm), was prepared by grafting PDEAAm-NH2 (obtained by RAFT polymerization) onto the activated Dawson acyl-POM, α2-[P2W17O61SnCH2CH2C(O)]6−. Extensive MS analysis was used to monitor the chain-functionalization steps and to confirm the formation of the hybrid. Aqueous solutions of the (NH4)7[POM–PDEAAm] exhibited a LCST of 38 °C. Thus, the solubility/aggregation of the hybrid was reversibly controlled by changing the temperature. Above 38 °C, the solution became cloudy, and cleared again upon cooling. Dynamic light scattering (DLS) revealed the formation of small aggregates in the range 100 nm. We assumed that the charged POM head units prevented the formation of the larger-scattering aggregates that are usually observed for PDEAAm, and promoted the formation of micelle-like structures. The conjugate exhibited a temperature transition, which was different from that of the polymer and depended on the counterions associated with the POM. This result demonstrates the potential for merging organic (in this case, polymer) and inorganic structures to afford materials that exhibit new properties.
    Mots-clés : aggregation, COS, GOBS, MACO, organic-inorganic hybrid composites, POLE 1, POLE 3, POLE 4, POLYMERES, polymerization, Polyoxometalates, SUPRA, thermoresponsive polymers.


  • M. Roger, A. Clavreul, N. T. Huynh, C. Passirani, P. Schiller, A. Vessières, C. Montero-Menei, et P. Menei, « Ferrociphenol lipid nanocapsule delivery by mesenchymal stromal cells in brain tumor therapy », International Journal of Pharmaceutics, vol. 423, nᵒ 1, p. 63-68, 2012.
    Résumé : The prognosis of patients with malignant glioma remains extremely poor despite surgery and improvements in radio- and chemo-therapies. Thus, treatment strategies that specifically target these tumors have the potential to greatly improve therapeutic outcomes. “Marrow-isolated adult multilineage inducible” cells (MIAMI cells) are a subpopulation of mesenchymal stromal cells (MSCs) which possess the ability to migrate to brain tumors. We have previously shown that MIAMI cells were able to efficiently incorporate lipid nanocapsules (LNCs) without altering either their stem cell properties or their migration capacity. In this study, we assessed whether the cytotoxic effects of MIAMI cells loaded with LNCs containing an organometallic complex (ferrociphenol or Fc-diOH) could be used to treat brain tumors. The results showed that MIAMI cells internalized Fc-diOH-LNCs and that this internalization did not induce MIAMI cell death. Furthermore, Fc-diOH-LNC-loaded MIAMI cells produced a cytotoxic effect on U87MG glioma cells in vitro. This cytotoxic effect was validated in vivo after intratumoral injection of Fc-diOH-LNC-loaded MIAMI cells in a heterotopic U87MG glioma model in nude mice. These promising results open up a new field of treatment in which cellular vehicles and nanoparticles can be combined to treat brain tumors.
    Mots-clés : CHEMBIO, Glioma, Mesenchymal stromal cells, Nanocarriers, Organometallic compound, POLE 3.

  • A. Roux, Y. Xu, J. - F. Heilier, M. - F. Olivier, E. Ezan, J. - C. Tabet, et C. Junot, « Annotation of the Human Adult Urinary Metabolome and Metabolite Identification Using Ultra High Performance Liquid Chromatography Coupled to a Linear Quadrupole Ion Trap-Orbitrap Mass Spectrometer », Analytical Chemistry, vol. 84, nᵒ 15, p. 6429-6437, août 2012.
    Résumé : Metabolic profiles of biofluids obtained by atmospheric pressure ionization mass spectrometry-based technologies contain hundreds to thousands of features, most of them remaining unknown or at least not characterized in analytical systems. We report here on the annotation of the human adult urinary metabolome and metabolite identification from electrospray ionization mass spectrometry (ESI-MS)-based metabolomics data sets. Features of biological interest were first of all annotated using the ESI-MS database of the laboratory. They were also grouped, thanks to software tools, and annotated using public databases. Metabolite identification was achieved using two complementary approaches: (i) formal identification by matching chromatographic retention times, mass spectra, and also product ion spectra (if required) of metabolites to be characterized in biological data sets to those of reference compounds and (ii) putative identification from biological data thanks to MS/MS experiments for metabolites not available in our chemical library. By these means, 384 metabolites corresponding to 1484 annotated features (6S9 in negative ion mode and 825 in positive ion mode) were characterized in human urine samples. Of these metabolites, 192 and 66 were formally and putatively identified, respectively, and 54 are reported in human urine for the first time. These lists of features could be used by other laboratories to annotate their ESI-MS metabolomics data sets.
    Mots-clés : acids, CSOB, database, discriminating signals, excretion, glucuronide, pattern-recognition, phase, POLE 3, resolution, spectra, sulfate.


  • B. Rudolf, M. Salmain, E. Fornal, et A. Rybarczyk-Pirek, « Metallocarbonyl complexes of bromo- and dibromomaleimide: synthesis and biochemical application », Applied Organometallic Chemistry, vol. 26, nᵒ 2, p. 80-85, 2012.
    Résumé : Bromomaleimides react with cysteine residues to form thiomaleimides that can be further cleaved with TCEP (tris(2-carboxyethyl)phosphine) to regenerate the cysteine derivatives. Herein we report the preparation of new organometallic Fe complexes containing monobromo and dibromo maleimide ligands. Both of these complexes were characterised by X-ray diffraction. Organometallic bromomaleimide derivatives were reacted with the thiol-containing biomolecules: cysteine ethyl ester hydrochloride, glutathione and papain. These cysteine-containing molecules underwent a substitution reaction with metallocarbonyl bromo- or dibromo maleimide complexes, followed by an addition reaction to the thio-maleimide double bond if thiol was added in excess. The metallocarbonyl mono-bromomaleimide complex was shown to inhibit the peptidase activity of the enzyme papain. The resulting papain–maleimide product could be cleaved by addition of TCEP to regenerate the catalytically active enzyme. Copyright © 2012 John Wiley & Sons, Ltd.
    Mots-clés : biometalloorganic chemistry, bromomaleimides, CHEMBIO, metallocarbonyl complexes, papain inhibitors, POLE 3.


  • L. Ruhlmann, D. Schaming, I. Ahmed, A. Courville, J. Canny, et R. Thouvenot, « Spectroscopic and Electrochemical Study of the Interconversion and Decomplexation of Cobalt(II) Sandwich Polyoxometalates Based on a Dawson-Type Anion », Inorganic Chemistry, vol. 51, nᵒ 15, p. 8202-8211, 2012.
    Résumé : The reaction of the trivacant Dawson polyoxometalate α-[P2W15O56]12? and the divalent cations Co2+ is known to form a symmetrically derived sandwich complex of formula ??-[Co4(H2O)2(P2W15O56)2]16? [symbolized as ??-Co4(P2W15)2] at low pH (ca. pH 3). We have shown previously that, by a slight modification of the reaction conditions, trinuclear α?-[(NaOH2)Co3(H2O)(P2W15O56)2]17? and dinuclear [(NaOH2)2Co2(P2W15O56)2]18? complexes [symbolized as α?-NaCo3(P2W15)2 and Na2Co2(P2W15)2, respectively] can be synthesized as aqueous-soluble sodium salts. α?-NaCo3(P2W15)2 is a ?lacunary? sandwich complex that can add a Co2+ cation to form nearly quantitatively an unsymmetrical Dawson tetracobalt sandwich polyoxometalate, α?-[Co4(H2O)2(P2W15O56)2]16? [symbolized as α?-Co4(P2W15)2]. Thus, for Co4(P2W15)2, the junctions between the trivacant {P2W15} subunits and the central tetrameric unit can be either both ? type or ? and α types. The interconversion between α?-Co4(P2W15)2 and ??-Co4(P2W15)2 and the decomplexation process at low pH, leading to the formation of α?-NaCo3(P2W15)2 and/or Na2Co2(P2W15)2, have been followed in aqueous solution at various pH values by electrochemistry, UV?visible absorption spectroscopy, and 31P NMR spectroscopy.
    Mots-clés : E-POM, POLE 2, POM.


  • M. Salmain, M. Ghasemi, S. Boujday, et C. - M. Pradier, « Elaboration of a reusable immunosensor for the detection of staphylococcal enterotoxin A (SEA) in milk with a quartz crystal microbalance », Sensors and Actuators B: Chemical, vol. 173, p. 148-156, 2012.
    Résumé : An immunosensor with quartz crystal microbalance (QCM) detection operating in flow-through mode was set up for assaying staphylococcal enterotoxin A (SEA) in model buffer medium and in milk. This biosensor is label-free and operates in the direct format. Each step of construction of the sensing layer comprising the capture anti-SEA antibody was investigated at the molecular level and optimized. The molecular layer was built using either amine- or acid-terminated thiols, with and without adding protein A to immobilize anti-SEA. The most efficient strategy to immobilize the antibody was selected on the basis of the biosensor's response to a standard solution of SEA. The optimized sensing layer was successfully used for the direct and fast (15 min) assay of SEA in phosphate buffer by QCM within a working range of 0.05-1 mg L−1 and a limit of detection of 0.02 mg L−1. Using a sandwich type assay, the response was amplified by a factor of 2 and consequently the lowest measurable concentration dropped down to 0.007 mg L−1 for a total assay time of 25 min. Furthermore, sensor regeneration was achieved in good conditions with low pH buffer releasing solution. Two levels of regeneration were reached, the first one, up to the binding protein level, necessitating the rebinding of anti-SEA. In this case the response of the regenerated sensor was 73% in the first cycle then stabilized at 60% of the primary response. For the second level, the capture antibody was cross-linked to the underlayer of protein A and no further grafting was needed. In this second case, the response of the regenerated sensor was 65% of the primary response. Eventually, the piezoelectric immunosensor was successfully applied to the direct assay of SEA spiked in real milk samples.
    Mots-clés : Biosensor, CHEMBIO, POLE 3, Polyclonal antibody, Protein A, Quartz crystal microbalance (QCM), Regeneration, Staphylococcal enterotoxin A.


  • M. - P. Santoni, A. K. Pal, G. S. Hanan, M. - C. Tang, K. Venne, A. Furtos, P. Ménard-Tremblay, C. Malveau, et B. Hasenknopf, « Coordination-driven self-assembly of polyoxometalates into discrete supramolecular triangles », Chemical Communications, vol. 48, nᵒ 2, p. 200-202, 2012.
    Résumé : Pd(ii)-directed self-assembly of a 3-pyridyl grafted Lindqvist hexavanadate led to the formation of a unique trimeric species, as confirmed by a variety of techniques, including pulsed-field gradient NMR spectroscopy and high-resolution ESI mass spectrometry.
    Mots-clés : GOBS, POLE 3, SUPRA.


  • G. Sava, G. Jaouen, E. A. Hillard, et A. Bergamo, « Targeted therapy vs. DNA-adduct formation-guided design: thoughts about the future of metal-based anticancer drugs », Dalton Transactions, vol. 41, nᵒ 27, p. 8226-8234, juin 2012.
    Résumé : The development of metal-based anticancer drugs is mainly governed by the experience accumulated with cisplatin and its analogues. The synthesis is focused on adding appropriate leaving and non-leaving groups to a transition metal in order to get more favorable DNA binding properties, and the biological activity is tested in vitro, always in a second step, looking for the cell line that is killed at the lowest drug concentration. This strategy seems unproductive today for the area of new drug development where the knowledge on cancer genomics is suggesting the use of targets selectively expressed, or overexpressed by cancer cells. These targets almost always are proteins, constituting membrane receptors or components of crucial biochemical pathways. Some data indicate that the antitumor activity of cisplatin might also be due to the interaction with protein targets. This critical review examines the possibilities for metal-based drugs to challenge tumors with innovative strategies, based on genomic approaches, capitalizing on the chemical experiences with metals in medicine and focusing on the nature of the ligands which are added to a metal depending on the selected tumor cells and on their molecular targets.
    Mots-clés : CHEMBIO, POLE 3.

  • C. Schaeffer, A. M. Todea, P. Gouzerh, et A. Mueller, « Spontaneous self-assembly of a giant spherical metal-oxide Keplerate: addition of one building block induces "immediate'' formation of the complementary one from a constitutional dynamic library », Chemical Communications, vol. 48, nᵒ 3, p. 350-352, 2012.
    Résumé : The addition of dinuclear {Mo(2)} units to a dynamic library containing molybdates results in the spontaneous self-assembly of a giant spherical metal-oxide species of the type {(Mo)-Mo(5)}(12){Mo(2)}(30) while the required pentagonal {(Mo)Mo(5)} building blocks are "immediately'' formed.
    Mots-clés : bond, capsules, clusters, complexes, E-POM, Molybdenum, POLE 2, polyoxomolybdate, POM, raman intensities, spectra, supramolecular chemistry, topology.


  • A. Seyer, F. Fenaille, C. Féraudet-Tarisse, H. Volland, M. R. Popoff, J. - C. Tabet, C. Junot, et F. Becher, « Rapid Quantification of Clostridial Epsilon Toxin in Complex Food and Biological Matrixes by Immunopurification and Ultraperformance Liquid Chromatography-Tandem Mass Spectrometry », Analytical Chemistry, vol. 84, nᵒ 11, p. 5103-5109, 2012.
    Résumé : Epsilon toxin (ETX) is one of the most lethal toxins produced by Clostridium species and is considered as a potential bioterrorist weapon. Here, we present a rapid mass spectrometry-based method for ETX quantification in complex matrixes. As a prerequisite, naturally occurring prototoxin and toxin species were first structurally characterized by top-down and bottom-up experiments, to identify the most pertinent peptides for quantification. Following selective ETX immunoextraction and trypsin digestion, two proteotypic peptides shared by all the toxin forms were separated by ultraperformance liquid chromatography (UPLC) and monitored by ESI-MS (electrospray ionization-mass spectrometry) operating in the multiple reaction monitoring mode (MRM) with collision-induced dissociation. Thorough protocol optimization, i.e., a 15 min immunocapture, a 2 h enzymatic digestion, and an UPLC-MS/MS detection, allowed the whole quantification process including the calibration curve to be performed in less than 4 h, without compromising assay robustness and sensitivity. The assay sensitivity in milk and serum was estimated at 5 ng·mL?1 for ETX, making this approach complementary to enzyme linked immunosorbent assay (ELISA) techniques.
    Mots-clés : CSOB, POLE 3.


  • R. Shokri, F. Vonau, M. Cranney, D. Aubel, A. Narladkar, B. Isare, L. Bouteiller, L. Simon, et G. Reiter, « Consequences of Varying Adsorption Strength and Adding Steric Hindrance on Self-Assembly of Supramolecular Polymers on Carbon Substrates », The Journal of Physical Chemistry C, vol. 116, nᵒ 40, p. 21594-21600, oct. 2012.
    Résumé : We investigated the consequences of changes in adsorption strength and the influence of steric hindrance with respect to ordering of supramolecular polymers on surfaces. The focus is on the kinetics of domain formation and the guidance of this self-assembly process by the substrate. To demonstrate general features, we compared two molecules, both forming supramolecular polymers, bis(hexylureido)toluene (HUT) and bis(2-ethylhexylureido)toluene (EHUT), differing only in the architecture of the alkyl side groups, on two substrates. Although highly oriented pyrolytic graphite (HOPG) and epitaxial graphene (EG) grown on silicon carbide have identical chemical composition and nearly the same crystal lattice parameters at the surface, they differ significantly in adsorption strength. Due to its higher polarizability, HOPG adsorbs molecules much more strongly than EG. Nonetheless, even on EG, the formation of supramolecular polymers was guided by the symmetry of the substrate lattice, but at a much slower rate. Accelerating ordering on EG through appropriate solvent vapor annealing, we eventually observed similar triangular patterns of HUT molecules on both substrates. This indicates that the orientation of supramolecular polymers is not controlled by the strength of substrate–molecule interactions but rather by the possibility to establish registry with the substrate. However, such guiding influence of the substrate was lost, even on strongly adsorbing HOPG, when steric hindrance, generated by adding ethyl branches to the side chains of the HUT molecule, caused weak adsorption. As a consequence, EHUT molecules did not adsorb in a parallel but in more or less perpendicular orientation to the substrate, and the resulting patterns were not guided anymore by the symmetry of the substrate. This demonstrates that small modifications of a molecule like the addition of short side branches can lead to drastic changes in the self-assembly process.
    Mots-clés : POLE 4, POLYMERES.


  • R. Skanji, M. Ben Messaouda, Y. Zhang, M. Abderrabba, H. Szwarc, et F. Moussa, « Sequential photo-addition of glycine methyl-ester to [60]fullerene », Tetrahedron, vol. 68, nᵒ 12, p. 2713-2718, mars 2012.
    Résumé : While direct photo-addition of glycine-methyl-esters (GME) to [60]fullerene (C60) can yield a complex product mixture, only a fulleropyrrolidine (FP) mono-adduct has been characterized and the mechanism remains to be ascertained. We show here that visible light irradiation of a mixture of C60 and GME in the presence of oxygen is a direct route to synthesize sequentially higher FP poly-adducts through an unprecedented cyclization–deamination mechanism. Each step of this mechanism leads to a FP adduct involving the correlated addition of two GME radicals and the departure of an ammonia molecule.
    Mots-clés : C60-Polyadducts, Fulleropyrrolidine, Glycine-methyl-esters, GOBS, Photo-additions, POLE 3, [60]Fullerene.

  • L. Svilar, V. Stankov-Jovanovic, D. Lesage, H. Dossmann, et J. - C. Tabet, « High-resolution mass spectrometry and hydrogen/deuterium exchange study of mitorubrin azaphilones and nitrogenized analogues », Journal of Mass Spectrometry, vol. 47, nᵒ 8, p. 969-977, août 2012.
    Résumé : Azaphilones represent numerous groups of wild fungal secondary metabolites that exhibit exceptional tendency to bind to nitrogen atoms in various molecules, especially those containing the amine group. Nitrogenized analogues of mitorubrin azaphilones, natural secondary metabolites of Hypoxylon fragiforme fungus, have been detected in the fungal methanol extract in very low concentrations. Positive electrospray ionization interfaced with high-resolution mass spectrometry was applied for confirmation of the elemental composition of protonated species. Collision-induced dissociation (CID) experiments have been performed, and fragmentation mechanisms have been proposed. Additional information regarding both secondary metabolite analogue families has been reached by application of gas-phase proton/deuterium (H/D) exchanges performed in the collision cell of a triple quadrupole mass spectrometer. An incomplete H/D exchange with one proton less than expected was observed for both protonated mitorubrin azaphilones and their nitrogenized analogues. By means of the density functional theory, an appropriate explanation of this behavior was provided, and it revealed some information concerning gas-phase H/D exchange mechanism and protonation sites. Copyright (c) 2012 John Wiley & Sons, Ltd.
    Mots-clés : cd3co2d, cd3od, cid, CSOB, Cycloisomerization, D exchange, d2o, density, density functional theory, gas-phase, gas-phase H, hydrogen-deuterium exchange, ion-molecule reactions, lc-esi-ft, metabolite profiles, mitorubrins, ms, nd3, POLE 3.


  • Y. L. K. Tan, P. Pigeon, S. Top, E. Labbé, O. Buriez, E. A. Hillard, A. Vessières, C. Amatore, W. K. Leong, et G. Jaouen, « Ferrocenyl catechols: synthesis, oxidation chemistry and anti-proliferative effects on MDA-MB-231 breast cancer cells », Dalton Transactions, vol. 41, nᵒ 25, p. 7537-7549, juin 2012.
    Résumé : The synthesis and anti-tumoral properties of a series of compounds possessing a ferrocenyl group tethered to a catechol via a conjugated system is presented. On MDA-MB-231 breast cancer cell lines, the catechol compounds display a similar or greater anti-proliferative potency (IC50 values ranging from 0.48–1.21 μM) than their corresponding phenolic analogues (0.57–12.7 μM), with the highest activity found for species incorporating the [3]ferrocenophane motif. On the electrochemical timescale, phenolic compounds appear to oxidize to the quinone methide, while catechol moieties form the o-quinone by a similar mechanism. Chemical oxidation of selected compounds with Ag2O confirms this interpretation and demonstrates the probable involvement of such oxidative metabolites in the in vitro activity of these species.
    Mots-clés : CHEMBIO, POLE 3.


  • M. - A. Tehfe, J. Monot, M. Malacria, L. Fensterbank, J. - P. Fouassier, D. P. Curran, E. Lacôte, et J. Lalevée, « A Water-Compatible NHC-Borane: Photopolymerizations in Water and Rate Constants for Elementary Radical Reactions », ACS Macro Letters, vol. 1, nᵒ 1, p. 92-95, janv. 2012.
    Résumé : Rate constants for important elementary reactions of 2,4-dimethyl-1,2,4-triazol-3-ylidene borane (1) and its derived boryl radical have been measured in the presence and absence of water. Reactions including H-abstraction by tBuO?, and onward reactions of the derived radical with methyl acrylate (addition), iodopropane (halogen abstraction), and an iodonium salt (oxidation) are unaffected by the presence of a high concentration (1.5 M) of water. Extending these results, borane (1) has been found to be an efficient new co-initiator for the visible light photopolymerization of monomers in the presence of both air and water.
    Mots-clés : COS, MACO, POLE 1.


  • M. Tharcis, T. Breiner, J. Belleney, F. Boué, et L. Bouteiller, « Hydrogen bonded supramolecular polymers in protic solvents: role of multitopicity », Polymer Chemistry, vol. 3, nᵒ 11, p. 3093-3099, oct. 2012.
    Résumé : We describe the synthesis of macromolecular amphiphiles of various molar masses containing well-defined hydrophobic groups incorporating urea moieties. All compounds have the same proportion of associative hydrophobic groups and solubilising POE chains. However, a strong influence of both the number of associative groups per chain and the polydispersity is demonstrated. In water, where the interactions between stickers are strong, the monomer (bearing a single sticker) self-assembles into filaments, but all other compounds with more than one sticker per chain are insoluble. In methanol, where the interactions between stickers are weaker, neither the monomer nor the monodispersed dimer is assembled, whereas polydispersed chains with an average number of 2 or 3 stickers per chain self-assemble into filaments, leading to macroscopic gelation.
    Mots-clés : POLE 4, POLYMERES.


  • K. N. Tiwari, J. - P. Monserrat, A. Hequet, C. Ganem-Elbaz, T. Cresteil, G. Jaouen, A. Vessières, E. A. Hillard, et C. Jolivalt, « In vitro inhibitory properties of ferrocene-substituted chalcones and aurones on bacterial and human cell cultures », Dalton Transactions, vol. 41, nᵒ 21, p. 6451-6457, mai 2012.
    Résumé : Two series of ten chalcones and ten aurones, where ferrocene replaces the C ring and with diverse substituents on the A ring were synthesized. The compounds were tested against two antibiotic-sensitive bacterial strains, E. coli ATCC 25922 and S. aureus ATCC 25923, and two antibiotic-resistant strains, S. aureus SA-1199B and S. epidermidis IPF896. The unsubstituted compound and those with methoxy substitution showed an inhibitory effect on all bacterial strains at minimum inhibitory concentrations ranging between 2 and 32 mg L−1. For four of these compounds, the effect was bactericidal, as opposed to bacteriostatic. The corresponding organic aurones did not show growth inhibition, underscoring the role of the ferrocene group. The methoxy-substituted aurones and the unsubstituted aurone also showed low micromolar (IC50) activity against MRC-5 non-tumoral lung cells and MDA-MB-231 breast cancer cells, suggesting non-specific toxicity.
    Mots-clés :

    ong> CHEMBIO, POLE 3.


  • A. M. Todea, A. J. M. Al-Karawi, T. Glaser, S. Walleck, L. - M. Chamoreau, R. Thouvenot, P. Gouzerh, et A. Müller, « Encapsulation of Keggin-type anions in reduced molybdenum–iron-type Keplerates as a general phenomenon », Inorganica Chimica Acta, vol. 389, p. 107-111, 2012.
    Résumé : Upon standing in air at room temperature, acidified aqueous solutions (pH 2) obtained by dissolving sodium molybdate, iron(II) chloride, acetic acid and potassium dodecatungstoborate led to the formation of greenish thin plate crystals (1) containing discrete clusters. Upon drying 1 at room temperature crosslinking of the clusters occurs in a solid-state reaction which leads to compound 2. Based on crystallographic studies of 1 and on extensive physical characterization (vibrational, NMR, Mössbauer spectra and magnetic susceptibility measurements) of 2, it was shown that compounds 1 and 2 contain reduced spherical {Mo72Fe30} Keplerate-type shells encapsulating non-reduced tungstoborate Keggin-type anions. The properties and structures of these compounds are compared to related hybrid structures containing in principle easier reducible molybdophosphate or molybdosilicate cores. According to the results the present type of encapsulation can be considered as a general phenomenon.
    Mots-clés : Core–shell clusters, E-POM, host–guest chemistry, Keggin ions, Keplerate, POLE 2, POM.

  • V. Toum, G. Lhommet, et L. Dechoux, « Synthesis of Cyclohexa-1,3-dienamines by Formal [3+3] Cycloaddition », Synlett, nᵒ 16, p. 2349-2352, 2012.
    Résumé : Formal [3+3] cycloadditions of beta-carboxymethylenamino esters with acrolein derivatives give a range of cyclohexa-2,6-dicarboxymethyl-1,3-dienamines that are potential acceptordonor-acceptor systems.
    Mots-clés : acid chlorides, Aza-annulation, CHEMBIO, cyclization, cyclohexa-1,3-dienamines, derivatives, donor-acceptor systems, enamine chemistry, Heterocycles, imines, multicomponent reactions, POLE 3, [3+3] cycloaddition.


  • J. Vohlídal, E. S. Wilks, A. Yerin, A. Fradet, K. - H. Hellwich, P. Hodge, J. Kahovec, W. Mormann, et R. F. T. Stepto, « Terminology and nomenclature for macromolecular rotaxanes and pseudorotaxanes (IUPAC Recommendations 2012) », Pure and Applied Chemistry, vol. 84, nᵒ 10, p. 2135-2165, sept. 2012.

  • B. Wahl, H. Bonin, A. Mortreux, S. Giboulot, F. Liron, G. Poli, et M. Sauthier, « A General and Efficient Method for the Alkoxycarbonylation of alpha-Chloro Ketones », Advanced Synthesis & Catalysis, vol. 354, nᵒ 16, p. 3105-3114, nov. 2012.
    Résumé : The alkoxycarbonylation of alpha-chloro ketones with carbon monoxide in alcoholic solvents could be optimized to generate beta-keto esters in high yields using much lower catalyst loadings than previously reported in the literature. Among the different screened parameters, the nature of the ligand proved to be the most crucial one, the Xantphos ligand affording the highest yields. The scope of the reaction could then be extended to a wide variety of chloro ketones with different types of alcohols.
    Mots-clés : alkoxycarbonylation, allyl phosphates, alpha-chloro ketones, benzyl-chloride, beta,gamma-unsaturated esters, beta-ketoesters, bite angle, carbon monoxide, carbon-monoxide, carbonylation, catalysis, complexes, Palladium, palladium-catalyzed alkoxycarbonylation, POLE 1, ROCS, SSO, synthetic applications.


  • B. Wahl, S. Giboulot, A. Mortreux, Y. Castanet, M. Sauthier, F. Liron, et G. Poli, « Straightforward Synthesis of Allylated Keto Esters: The Palladium-Catalysed Haloketone Alkoxycarbonylation/ Allylation Domino Reaction », Advanced Synthesis & Catalysis, vol. 354, nᵒ 6, p. 1077–1083, 2012.
    Résumé : The palladium-catalysed α-chloro ketone methoxycarbonylation and allylic alkylation reactions can be efficiently combined to provide a new catalytic domino reaction. The first, carbonylative, step generates the β-keto ester, which acts as the nucleophile in a subsequent allylation step. The use of allyl phenates in combination with Xantphos ligand are the key features allowing one to obtain the allylated β-keto esters in good yields
    Mots-clés : Allylic alkylation, carbon monoxide, catalysis, Domino reaction, POLE 1, ROCS, selectivity, SSO.


  • S. L. Xiao, D. M. Zhou, M. Yang, F. Yu, L. H. Zhang, P. Sinaÿ, et Y. M. Zhang, « Synthesis of two mono-deoxy β-cyclodextrin derivatives as useful tools for confirming DIBAL-H promoted bis-de-O-methylation mechanism », Chinese Chemical Letters, vol. 23, nᵒ 12, p. 1315-1318, 2012.
    Résumé : Diisobutylaluminium hydride (DIBAL-H) promotes secondary rim regioselective bis-de-O-methylation of permethylated β-cyclodextrin (β-CD) to give diol 2. To gain an insight into the mechanism of this remarkable regioselective behavior, two corresponding permethylated β-CDs with an alcohol function at either 2- or 3-position were synthesized in our previous study. As a step further to this work, the two compounds were subjected to deoxygenation reaction with tributyltin hydride in the present of 2,2′-azobisisobutyronitrile affording the corresponding 2- and 3-deoxy permethylated β-CD derivatives (19 and 16). The structures of these two compounds were characterized by 1D and 2D NMR and HRMS. Compounds 16 and 19 were unable to react with DIBAL-H which suggests that O-2A and O-3B are necessary for DIBAL-H promoted bis-de-O-methylation reaction of permethylated β-CD.
    Mots-clés : Cyclodextrin (CD), Deoxy, DIBAL-H, GOBS, Mechanism, POLE 3, Synthesis.


  • S. -long Xiao, Q. Wang, F. Yu, Y. -yun Peng, M. Yang, M. Sollogoub, P. Sinaÿ, Y. -min Zhang, L. -he Zhang, et D. -min Zhou, « Conjugation of cyclodextrin with fullerene as a new class of HCV entry inhibitors », Bioorganic & Medicinal Chemistry, vol. 20, nᵒ 18, p. 5616-5622, sept. 2012.
    Résumé : An α-cyclodextrin–[60]fullerene conjugate with a flexible linker at the secondary face of α-cyclodextrin has been prepared, which displays significant water solubility and, more importantly, acts as a new class of HCV entry inhibitor with IC50 at 0.17 μM level.
    Mots-clés : Conjugate, Fullerene, GOBS, HCV entry, POLE 3, α-Cyclodextrin.


  • J. - Y. Xu, H. - B. Song, G. - F. Xu, X. Qiao, S. - P. Yan, D. - Z. Liao, Y. Journaux, et J. Cano, « A new enneanuclear nickel (II) cluster with a rectangular face-centered trigonal prism structure and cluster glass behavior », Chemical Communications, vol. 48, nᵒ 7, p. 1015-1017, 2012.


  • S. - H. Yan, Y. - Y. Zhao, H. - S. Zeng, Y. Zhang, R. - C. Lin, et W. - J. Sun, « Chemical composition and antioxidant activities of extracts from <i>Apocyni Veneti Folium</i> », Natural Product Research, vol. 26, nᵒ 7, p. 600-608, 2012.


  • S. - J. Yoon, J. H. Kim, K. S. Kim, J. W. Chung, B. Heinrich, F. Mathevet, P. Kim, B. Donnio, A. - J. Attias, D. Kim, et S. Y. Park, « Mesomorphic Organization and Thermochromic Luminescence of Dicyanodistyrylbenzene-Based Phasmidic Molecular Disks: Uniaxially Aligned Hexagonal Columnar Liquid Crystals at Room Temperature with Enhanced Fluorescence Emission and Semiconductivity », Advanced Functional Materials, vol. 22, nᵒ 1, p. 61-69, janv. 2012.
    Résumé : A new dicyanodistyrylbenzene-based phasmidic molecule, (2Z,2′Z)-2,2′-(1,4-phenylene)bis(3-(3,4,5-tris(dodecyloxy)phenyl)acrylonitrile), GDCS, is reported, which forms a hexagonal columnar liquid crystal (LC) phase at room temperature (RT). GDCS molecules self-assemble into supramolecular disks consisting of a pair of molecules in a side-by-side disposition assisted by secondary bonding interactions of the lateral polar cyano group, which, in turn, constitute the hexagonal columnar LC structure. GDCS shows very intense green/yellow fluorescence in liquid/solid crystalline states, respectively, in contrast to the total absence of fluorescence emission in the isotropic melt state according to the characteristic aggregation-induced enhanced emission (AIEE) behavior. The AIEE and two-color luminescence thermochromism of GDCS are attributed to the peculiar intra- and intermolecular interactions of dipolar cyanostilbene units. It was found that the intramolecular planarization and restricted molecular motion associated with a specific stacking situation in the liquid/solid crystalline phases are responsible for the AIEE phenomenon. The origin of the two-color luminescence was elucidated to be due to the interdisk stacking alteration in a given column driven by the specific local dipole coupling between molecular disks. These stacking changes, in turn, resulted in the different degree of excited-state dimeric coupling to give different emission colors. To understand the complicated photophysical properties of GDCS, temperature-dependent steady-state and time-resolved PL measurements have been comprehensively carried out. Uniaxially aligned and highly fluorescent LC and crystalline microwires of GDCS are fabricated by using the micromolding in capillaries (MIMIC) method. Significantly enhanced electrical conductivity (0.8 × 10−5 S•cm−1/3.9 × 10−5 S•cm−1) of the aligned LC/crystal microwires were obtained over that of multi-domain LC sample, because of the almost perfect shear alignment of the LC material achieved in the MIMIC mold.
    Mots-clés : electro–optical materials, liquid crystals, POLE 4, POLYMERES, structure–property relationships.


  • H. Yu, F. Stoffelbach, C. Detrembleur, C. - A. Fustin, et J. - F. Gohy, « Nanoporous thin films from ionically connected diblock copolymers », European Polymer Journal, vol. 48, nᵒ 5, p. 940-944, 2012.
    Résumé : An ionically connected polystyrene-block-poly(ethylene oxide) diblock copolymer (PS−+PEO) has been prepared by blending a PEO block functionalized by a dimethylamino group at one extremity with a sulfonic acid terminated PS block. Proton transfer occurs from the sulfonic acid to the dimethylamino group, resulting in the formation of an ion pair acting as a junction between the two polymer blocks. This copolymer was further used to prepare thin films with a cylindrical morphology consisting of PEO cylinders embedded in a PS matrix and oriented perpendicularly to the film surface. Nanoporous thin films with sulfonate groups on the pore walls have been finally obtained after solvent extraction of the PEO microphases. The presence of those sulfonate groups was evidenced by grafting a positively charged fluorescent dye on the pore walls.
    Mots-clés : Blends, Block copolymers, Ionic interactions, POLE 4, POLYMERES, Self-assembly, thin films.


  • S. Zhang, L. Dias Goncalves, H. Lefebvre, M. Tessier, B. Rousseau, et A. Fradet, « Direct Poly(β-alanine) Synthesis via Polycondensation in Ionic Liquids », ACS Macro Letters, vol. 1, nᵒ 8, p. 1079-1082, 2012.
    Résumé : Poly(β-alanine) was successfully synthesized by an alternative method, which is the direct polyamidation of β-alanine in ionic liquids with triphenylphosphite as a condensing agent. It was found that 1,3-dimethylimidazolium dimethylphosphate was the most suitable reaction medium, in which a number-average degree of polymerization up to 49.5 was obtained. It was shown that the method is also applicable to the direct synthesis of polypeptides, for example, poly(l-valine) and poly(l-isoleucine).
    Mots-clés : POLE 4, POLYMERES.


  • W. Zhang, F. D’Agosto, O. Boyron, J. Rieger, et B. Charleux, « Toward a Better Understanding of the Parameters that Lead to the Formation of Nonspherical Polystyrene Particles via RAFT-Mediated One-Pot Aqueous Emulsion Polymerization », Macromolecules, vol. 45, nᵒ 10, p. 4075-4084, 2012.
    Résumé : The emulsion polymerization of styrene in the presence of hydrophilic poly(methacrylic acid-co-poly(ethylene oxide) methyl ether methacrylate), P(MAA-co-PEOMA), macromolecular RAFT (reversible addition–fragmentation chain transfer) agents possessing a trithiocarbonate reactive group and 19 ethylene oxide subunits in the grafts was performed to create in situ P(MAA-co-PEOMA)-b-polystyrene amphiphilic block copolymer self-assemblies. The system was studied using the following conditions: a pH of 5, two different compositions of the MAA/PEOMA units (50/50 and 67/33, mol/mol), different molar masses of the macroRAFT agents, and various concentrations of the latter targeting different molar masses for the polystyrene block. This work completes a previous one performed at pH 3.5, under otherwise similar experimental conditions, for which only spherical particles were obtained [Zhang et al. Macromolecules2011, 44, 7584]. For both MAA/PEOMA compositions, the system led to different nano-object morphologies such as spherical micelles, nanofibers, and vesicles, depending directly on the molar masses of the hydrophilic and hydrophobic blocks. A pH of 5 was shown to be the best compromise to achieve nonspherical particles while keeping a good control over the chain growth.
    Mots-clés : POLE 4, POLYMERES.


  • X. Zhang, S. Boissé, C. Bui, P. - A. Albouy, A. Brûlet, M. - H. Li, J. Rieger, et B. Charleux, « Amphiphilic liquid-crystal block copolymer nanofibers via RAFT-mediated dispersion polymerization », Soft Matter, vol. 8, nᵒ 4, p. 1130-1141, janv. 2012.
    Résumé : Well-defined, cholesteryl-based, amphiphilic block copolymer nanofibers have been obtained in a simple, one-pot, ethanol/water dispersion polymerization process using poly((meth)acrylic acid-co-(poly(ethylene glycol) (meth)acrylate) copolymers end-functionalized by a reactive trithiocarbonate end-group as macromolecular reversible addition–fragmentation chain transfer agents (macroRAFT agents). The resulting highly concentrated dispersions were analyzed by TEM (transmission electron microscopy), cryo-TEM, SAXS (small angle X-ray scattering) and SANS (small angle neutron scattering), which allowed the shape and size of the nanoobjects formed in situ to be fully characterized and which revealed moreover the presence of a smectic order in the hydrophobic cores. Due to this particular substructure, the nanofiber organization was observed over a broad composition range of the amphiphilic block copolymers.
    Mots-clés : POLE 4, POLYMERES.


  • X. Zhang, J. Rieger, et B. Charleux, « Effect of the solvent composition on the morphology of nano-objects synthesized via RAFT polymerization of benzyl methacrylate in dispersed systems », Polymer Chemistry, vol. 3, nᵒ 6, p. 1502-1509, mai 2012.
    Résumé : A hydrophilic macromolecular RAFT (reversible addition–fragmentation chain transfer) agent (macroRAFT agent) composed of 50 mol% methacrylic acid and 50 mol% poly(ethylene oxide) monomethyl ether methacrylate end-capped by a reactive trithiocarbonate group (P(MAA-co-PEOMA)) was used in the polymerization of benzyl methacrylate (BzMA) in different media, ethanol–water and 1,4-dioxane–water mixtures. Depending on the solvent composition, the polymerization showed features of either a dispersion polymerization (monomer soluble in the initial medium) or an emulsion polymerization (monomer insoluble in the initial medium). In all cases, the RAFT mechanism led to the in situ formation of well-defined amphiphilic P(MAA-co-PEOMA)-b-PBzMA block copolymers that self-assembled during the growth step into self-stabilized nano-objects, according to a polymerization-induced micellization process. For a given composition of the block copolymer, the final morphology depended strongly on the solvent composition. The presence of the organic co-solvent was favorable to the formation of fibers while an increased amount of water favored the formation of spherical particles. Compared to the ethanol–water system, in which the non-spherical objects existed only above 77–80 vol% of ethanol, in 1,4-dioxane–water mixtures the morphological transition was observed at a lower proportion of organic co-solvent (close to 20 vol%). For a given molar mass of the macroRAFT agent and an increased molar mass of the PBzMA block in a given solvent composition (ethanol–water, 95/5, v/v), the morphology changed from spheres to fibers and then to large spheres or vesicles. The molar mass window in which fibers were obtained was wider than that observed in pure water at pH 5 using the same macroRAFT agent [X. Zhang et al., Macromolecules, 2011, 44, 4149].
    Mots-clés : POLE 4, POLYMERES.


  • Q. Zhao, D. Curran, M. Malacria, L. Fensterbank, J. - P. Goddard, et E. Lacôte, « NHC-Catalyzed Chemo- and Regioselective Hydrosilylation of Carbonyl Derivatives », Synlett, vol. 23, nᵒ 03, p. 433-437, janv. 2012.

  • W. Zhao, J. He, Y. Zhang, Y. Ito, Q. Su, et W. Sun, « Preparative Isolation and Purification of Alkaloids from Picrasma Quassiodes (d. Don) Benn. by High-Speed Countercurrent Chromatography », Journal of Liquid Chromatography & Related Technologies, vol. 35, nᵒ 11, p. 1597-1606, 2012.
    Résumé : By using a two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (2: 2: 2: 2, v/v/v/v), a high-speed counter-current chromatography technique was successfully used for isolation and purification of three alkaloids from Picrasma quassiodes (D. Don) Benn. for the first time. A total of 22.1 mg of 3-methylcanthin-2,6-dione, 4.9 mg of 4-methoxy-5-hydroxycanthin-6-one and 1.2 mg of 1-methoxycarbonyl-beta-carboline were obtained from 100 mg of crude extract of Picrasma quassiodes (D. Don) Benn. in less than 5 hr, with purities of 89.30%, 98.32%, and 98.19%, respectively. The target compounds were identified by ESI-MS, H-1 NMR, and C-13 NMR.
    Mots-clés : 1-methoxycarbonyl-beta-carboline, 3-methylcanthin-2,6-dione, 4-methoxy-5-hydroxycanthin-6-one, Alkaloids, beta-carboline alkaloids, GOBS, high-speed countercurrent chromatography, Picrasma quassiodes, POLE 3, separation.

  • Y. - Y. Zhao, X. - L. Cheng, F. Wei, X. - Y. Xiao, W. - J. Sun, Y. Zhang, et R. - C. Lin, « Serum metabonomics study of adenine-induced chronic renal failure in rats by ultra performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry », Biomarkers, vol. 17, nᵒ 1, p. 48-55, févr. 2012.
    Résumé : An ultra performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC Q-TOF MS) metabonomics approach was employed to study the serum metabolic profiling of adenine-induced chronic renal failure (CRF) rats. Acquired data were subjected to principal component analysis (PCA) for differentiating the CRF and the normal control groups. Potential biomarkers were screened by using S-plot and were identified by the accurate mass, isotopic pattern and MS/MS fragments information obtained from UPLC Q-TOF MS analysis. Significant differences in the serum level of creatinine, amino acids and LysoPCs were observed, indicating the perturbations of amino acid metabolism and phospholipid metabolism in adenine-induced CRF rats. This research proved that metabonomics is a promising tool for disease research.
    Mots-clés : activation, biomarkers, Chronic renal failure, GOBS, inborn-errors, kidney, metabolism, metabonomics, nmr-spectroscopy, pathway, POLE 3, principal component analysis, Rats, serum, tof ms, uplc, uplc q-tof ms.

  • Z. - Y. Zhu, J. Chen, C. - L. Si, N. Liu, H. - Y. Lian, L. - N. Ding, Y. Liu, et Y. - M. Zhang, « Immunomodulatory effect of polysaccharides from submerged cultured Cordyceps gunnii », Pharmaceutical Biology, vol. 50, nᵒ 9, p. 1103-1110, sept. 2012.
    Résumé : Context: The genus Cordyceps (Clavicipitaceae) is a group of entomopathogenic fungi that is widely used as tonic food or invigorant with broad-spectrum medicinal properties in China. Cordyceps gunnii (Berk.) Berk (C. gunnii), is also well known as the Chinese rare caterpillar fungus and has similar pharmacological activities with Cordyceps sinensis (C. sinensis). Polysaccharides (PS) from various Cordyceps species have demonstrated many interesting biological activities, including antitumor, immunopotentiation, hypoglycemic, and hypocholesterolemic activities. Objective: To investigate the effect of C. gunnii PS on the immunostimulatory antitumor function and expression of immune related cytokines in normal, immuno-suppressive, and H22-bearing mice, respectively. Methods: C. gunnii PS were extracted with hot water at 80 C for 2 h. Normal, immuno-suppressive, and H22-bearing mice were treated with PS respectively. By detecting the value of macrophage phagocytic index, proliferation of lymphocytes, natural killer (NK) cell activity and expression of related cytokines, interleukin (IL-4), tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma), and tumor inhibition index in H22-bearing mice additionally, the effect of PS on immunostimulatory antitumor function and its mechanism were studied. Results: The total sugar content of the PS was determined to be 95% after purification. PS markedly increased the thymus and spleen indexes, the macrophage phagocytosis, the proliferation of splenic cells, and the level of IFN-gamma and TNF-alpha. In tumor growth inhibition test, PS showed remarkable inhibition effects. Conclusion: PS from the C. gunnii could enhance nonspecific immunological function, humoral immunity, cellular immunity in mice, and inhibit tumor growth.
    Mots-clés : Antitumor, Cordyceps, expression, GOBS, mice, nonspecific immunity, POLE 3, polysaccharides.


  • Z. - Y. Zhu, H. - Y. Lian, C. - L. Si, Y. Liu, N. Liu, J. Chen, L. - N. Ding, Q. Yao, et Y. Zhang, « The chromatographic analysis of oligosaccharides and preparation of 1-kestose and nystose in yacon », International Journal of Food Sciences and Nutrition, vol. 63, nᵒ 3, p. 338-342, 2012.
    Mots-clés : analysis, glucose-oxidase, GOBS, mixed-enzyme-system, oligosaccharide, POLE 3, separation, yacon.
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  • Z. - Y. Zhu, N. Liu, Y. Liu, C. - L. Si, R. - Q. Liu, J. Chen, C. - J. Liu, A. - J. Liu, et Y. - M. Zhang, « Chemical analysis of a polysaccharide from <i>Cristaria plicata</i> (Leach) », International Journal of Food Sciences and Nutrition, vol. 63, nᵒ 4, p. 506-511, 2012.
    Mots-clés : anodonta-cygnea, chemical composition, GOBS, hyriopsis-cumingii, isolation, mussel, POLE 3, Polysaccharide, purification, structure.
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  • Z. -yuan Zhu, N. Liu, C. -ling Si, Y. Liu, L. -na Ding, C. Jing, A. -jun Liu, et Y. -min Zhang, « Structure and anti-tumor activity of a high-molecular-weight polysaccharide from cultured mycelium of Cordyceps gunnii », Carbohydrate Polymers, vol. 88, nᵒ 3, p. 1072-1076, avr. 2012.
    Résumé : Cordyceps gunnii (berk.) Berk (C. Gunnii) is well known as a Chinese rare caterpillar fungus and has similar pharmacological activity with C. sinensis. In this work, a high-molecular-weight polysaccharide (CPS) was isolated and purified from the mycelia of C. gunnii. The total sugar content of CPS was amounted to 92.84%. The result of HPLC indicated that CPS was a homogeneous polysaccharide. The estimated average molecular weight of CPS was 3.72 x 10(6) Da. The specific rotation of CPS was recorded [alpha](D)(25) = +134.2 degrees. Its characteristic was determined by chemical analysis, gas chromatography, IR spectroscopy and NMR data. The results showed that CPS was mainly composed of glucose, and a small amount of rhamnose, arabinose, xylose, mannose and galactose with a molar ratio of Rha:Ara:Xyl:Man:Glu:Gal = 3.0:2.6:1.0:1.3:106.0:2.8. The main chain of CPS was majorly composed of alpha-(1 -> 4) glucose. The tumor inhibition ratio on K562 cell by CPS was 56.65%. (C) 2012 Elsevier Ltd. All rights reserved.
    Mots-clés : antioxidant activity, Antitu

    mor, cells, Characteristic, Cordyceps gunnii, GOBS, High-molecular-weight polysaccharide, mice, militaris, POLE 3, purification, sinensis.

  • Z. - Y. Zhu, Q. Yao, Y. Liu, C. - L. Si, J. Chen, N. Liu, H. - Y. Lian, L. - N. Ding, et Y. - M. Zhang, « Highly efficient synthesis and antitumor activity of monosaccharide saponins mimicking components of Chinese folk medicine Cordyceps sinensis », Journal of Asian Natural Products Research, vol. 14, nᵒ 5, p. 429-435, 2012.
    Résumé : Ergosterol 3-O-beta-D-glucopyranoside (1a) and ergosterol 3-O-beta-D-galactopyranoside (1b) were highly efficiently synthesized and evaluated for their inhibitory activities against two tumor cell lines. The structures of these compounds were extensively confirmed by H-1, C-13 NMR, IR, and HRMS. Compounds 1a and 1b exhibited interesting cytotoxic profiles. The antitumor activity of compound 1a was higher than that of 1b.
    Mots-clés : Cordyceps sinensis, Ergosterol, Glycosylation, GOBS, POLE 3, saponins.

2011

Année non précisée


  • « Thieme E-Journals - Synlett / Abstract », sans date. [Online]. Available: https://www.thieme-connect.com/products/ejournals/abstract/10.1055/s-0040-1707467. [Accessed: 15-mars-2021].

  • « Photoredox Catalysis, an Opportunity for Sustainable Radical Chemistry | Advanced Green Chemistry », sans date. [Online]. Available: https://www.worldscientific.com/doi/pdf/10.1142/9789811210587_0003?download=true. [Accessed: 21-mai-2021].

  • Full Text PDF


  • T. Deis, J. Maury, F. Medici, M. Jean, J. Forte, N. Vanthuyne, L. Fensterbank, et G. Lemière, « Synthesis and Optical Resolution of Configurationally Stable Zwitterionic Pentacoordinate Silicon Derivatives », Angewandte Chemie International Edition, vol. n/a, nᵒ n/a, sans date.
    Résumé : Stereogenic silicon centres in functionalised tetracoordinated organosilanes generally exhibit very high configurational stability under neutral conditions. This stability drops completely when higher coordination states of the silicon centre are reached due to rapid substituent exchange. Herein we describe the synthesis of chiral and neutral pentacoordinate silicon derivatives with high configurational stability. The zwitterionic nature of these air- and water-tolerant species allows for the first time their direct and efficient optical resolution using chiral HPLC techniques. By means of this method, pentacoordinate silicon compounds exhibiting high Si-inversion have been obtained as single enantiomers. A rationalisation of the enantiomerisation pathways has been also carried out using DFT calculations.
    Mots-clés : Chiral HPLC, Chirality, MACO, Optical resolution, POLE 1, Silicon, Zwitterion.


  • L. G. Fensterbank, E. Levernier, K. Jaouadi, H. - R. Zhang, V. Corcé, A. Bernard, G. Gontard, C. Troufflard, L. Grimaud, E. Derat, et C. Ollivier, « Phenyl Silicates with Substituted Catecholate Ligands: Synthesis, Structural Studies and Reactivity », Chemistry – A European Journal, vol. n/a, nᵒ n/a, sans date.
    Résumé : While the generation of aryl radicals by photoredox catalysis is well-documented under reductive conditions, it has remained challenging under an oxidative pathway. Because of the easy photooxidation of alkyl bis-catecholato silicates, a general study on phenyl silicates bearing substituted catecholate ligands has been achieved. The newly synthesized phenyl silicates have been fully characterized and their reactivity has been explored. It was found that thanks to the substitution of the catecholate moiety and notably with the 4-cyanocatecholato ligand, the phenyl radical could be generated and trapped. Computational studies provided a rationale for these findings.
    Mots-clés : catalysisDFT, CHEMBIO, MACO, photoredox, radical, redox, silicatesphenyl.
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  • K. Tõnsuaadu, M. Gruselle, F. Kriisa, A. Trikkel, P. Gredin, et D. Villemin, « Dependence of the interaction mechanisms between l-serine and O-phospho-l-serine with calcium hydroxyapatite and copper modified hydroxyapatite in relation with the acidity of aqueous medium - Dimensions », sans date. [Online]. Available: https://app.dimensions.ai/details/publication/pub.1105431010?and_facet_journal=jour.1116242&and_facet_for=2471. [Accessed: 20-déc.-2018].
    Résumé : Motivated by the role of copper ions in biological processes the aim of this study was to elucidate the impact of copper ions bound to hydroxyapatite on L-serine (L-Ser) and O-phospho-L-serine (O-Ph-L-Ser) adsorption at different acidity of aqueous solutions. The adsorption phenomenon was studied by FTIR, UV, and AA spectroscopy, XRD and thermal analysis methods together with the evolved gases analysis taking into consideration the ionic state of the amino acids as well as the apatite surface state, which are tightly correlated with the solution pH. In acidic solution, the main process involves apatite dissolution releasing calcium and copper ions. At pH > 5 the complexation of amino acids with Ca2+ or Cu2+ ions is more important leading also to the release of cations. The ability of copper ions to form water soluble complexes with L-Ser and O-Ph-L-Ser leads to an important loss of these ions, while calcium release is very low at this pH. Therefore, the use of copper ions substituting calcium in the apatite structure to enhance the ability of amino acids adsorption on the apatite surface seems problematic even at pH > 5.
    Mots-clés : ARC, POLE 1.
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