Nos tutelles

CNRS

Rechercher





Accueil > Les équipes > Glycochimie Organique Biologique et Supramoléculaire (GOBS) > Publications

Publications

publié le , mis à jour le

2016



  • M. W. Cooke, M. - P. Santoni, B. Hasenknopf, et G. S. Hanan, « Heteroleptic ruthenium(II) chromophores based on tunable polytopic 4′-(benzamidinato)-2,2′:6′,2′′-terpyridines », vol. 45, nᵒ 44, p. 17850-17858.
    Résumé : A modulable and simple approach towards heteroleptic ruthenium(II) complexes of amidine-based polypyridine ligands is presented. New complexes 1 and 2 ([(terpyridine)Ru(terpyridine-C6H4-C(NR)(NHR))]2+ with R = propyl and R = phenyl derivatives, respectively) were characterized by NMR spectroscopy in solution and by X-ray diffraction, which confirmed the obtention of the (E) stereoisomer alone. Depending on the bulkiness of the R-substituents introduced on the amidine moiety, rotational isomerism around the C–N bond could be observed at r.t. Spectroscopic and electrochemical studies showed that the nature of the R-substituents introduced on the amidine moiety can significantly influence the redox and ground-state acido-basic properties of the complexes, while maintaining their electronic features. This particular tunability of polytopic 4′-(amidinato)-terpyridines offers an interesting perspective for photoactive units in larger multi-functional arrays.
    Mots-clés : GOBS, POLE 3.


  • L. Duarte, S. Nag, M. Castro, E. Zaborova, M. Ménand, M. Sollogoub, V. Bennevault, J. - F. Feller, et P. Guégan, « Chemical Sensors Based on New Polyamides Biobased on (Z) Octadec-9-Enedioic Acid and β-Cyclodextrin », Macromolecular Chemistry and Physics, vol. 217, nᵒ 14, p. 1620-1628.


  • S. L. Gac, B. Boitrel, M. Sollogoub, et M. Ménand, « Protonated hexaphyrin–cyclodextrin hybrids: molecular recognition tuned by a kinetic-to-thermodynamic topological adaptation », vol. 52, nᵒ 60, p. 9347-9350.
    Résumé : Protonation study of [26/28]hexaphyrin-capped cyclodextrins revealed a temperature controlled conformational transition of the cap. The hexaphyrin undergoes a rectangular-to-triangular shape-shifting which strongly modifies the shape of the confined environment featured by the hybrids, and ultimately affects the encapsulation of the counterions. It provides an attractive access to innovative allosteric host–guest systems.
    Mots-clés : GOBS, POLE 3.


  • Y. Gao, Z. Cao, C. Su, Z. Chen, X. He, F. Ding, H. Li, et Y. Zhang, « Chiron Approaches to the Antitumor Natural Product Fuzanin D », Synthesis, vol. 48, nᵒ 24, p. 4471-4476.
    Résumé : Thieme E-Books & E-Journals
    Mots-clés : GOBS, POLE 3.


  • Y. Gao, X. He, F. Ding, et Y. Zhang, « Recent Progress in Chemical Syntheses of Sphingosines and Phytosphingosines », Synthesis, vol. 48, nᵒ 23, p. 4017-4037.
    Résumé : Thieme E-Books & E-Journals
    Mots-clés : GOBS, POLE 3.


  • X. Han, Y. Shi, L. Si, Z. Fan, H. Wang, R. Xu, P. Jiao, K. Meng, Z. Tian, X. Zhou, H. Jin, X. Wu, H. Chen, Y. Zhang, L. Zhang, S. Xiao, et D. Zhou, « Design, synthesis and biological activity evaluation of novel conjugated sialic acid and pentacyclic triterpene derivatives as anti-influenza entry inhibitors », vol. 7, nᵒ 10, p. 1932-1945.
    Résumé : Influenza virus is a major human pathogen that causes annual epidemics and occasional pandemics. Recently, plant-derived pentacyclic triterpenes have been shown to act as highly potent anti-viral agents by efficiently preventing the attachment of the virion to the host cells. In this report, we conjugated sialic acid with oleanolic acid (OA), a natural product with broad antiviral entry activity, as well as three other analogs echinocystic acid (EA), ursolic acid (UA) and betulinic acid (BA). A total of 24 conjugated sialic acid and pentacyclic triterpene derivatives with different linkers were synthesized and evaluated for antiviral activity against influenza A/WSN/33 (H1N1) virus in MDCK cell culture. The most potent compound had an IC50 of 41.2 μM. Time-of-addition, hemagglutination inhibition (HI), surface plasmon resonance (SPR) and molecular docking assays demonstrated that compound 20a acted as an influenza virus entry inhibitor by preventing the binding of influenza virus hemagglutinin (HA) protein to host cells.
    Mots-clés : GOBS, POLE 3.

  • X. - C. Liu, Z. - Y. Zhu, Y. - L. Tang, M. -fei Wang, Z. Wang, A. - J. Liu, et Y. - M. Zhang, « Structural properties of polysaccharides from cultivated fruit bodies and mycelium of Cordyceps militaris », Carbohydrate Polymers, vol. 142, p. 63-72.
    Résumé : The structural properties of polysaccharides, respectively, obtained from the fermented mycelium and cultivated fruiting bodies of the Cordyceps militaris were investigated and compared in this paper. First, the crude polysaccharides were extracted from the mycelium and the fruiting bodies, respectively. The polysaccharides were successively purified by Sevag and chromatography on Sephadex G-100 column to produce two polysaccharides fractions termed CMPS-II and CBPS-II, respectively. The average molecular weights of CMPS-II and CBPS-II were 1.402×10(3) kDa and 1.273×10(3) kDa, respectively, and they were mainly composed of mannose, glucose and galactose in the mole ratios of 1:28.63:1.41 and 1:12.41:0.74, respectively, for CMPS-II and CBPS-II. Afterward, the structural features of CMPS-II and CBPS-II were investigated by a combination of chemical and instrumental analysis, such as FT-IR, periodate oxidation-Smith degradation, GC-MS, NMR and methylation analysis. The results indicated that structurally, both CMPS-II and CBPS-II were 1,3-branched-galactomannoglucan that had a linear backbone of (1→4)-linked α-D-glucopyranose (Glcp). Congo-red test revealed that CMPS-II and CBPS-II existed as triple-helical chains in 0.05-0.15 M NaOH solution.
    Mots-clés : Cordyceps militaris, GOBS, POLE 3, Polysaccharide, structure.


  • Z. Liu, Q. Zheng, W. Chen, S. Man, Y. Teng, X. Meng, Y. Zhang, P. Yu, et W. Gao, « Paris saponin I inhibits proliferation and promotes apoptosis through down-regulating AKT activity in human non-small-cell lung cancer cells and inhibiting ERK expression in human small-cell lung cancer cells », RCS Advances, vol. 6, nᵒ 75, p. 70816-70824.
    Résumé : Paris Saponin I (PSI), a steroidal saponin derivative extracted from a traditional Chinese herbal Paris polyphylla, has shown cytotoxic effects on several tumor cell lines. However, the mechanisms of its antitumor activity especially for lung cancers remain to be elucidated. In this present investigation, we continue to explore the efficacy and mechanisms underlying the cytotoxic effects of PSI in lung cancer cell lines. Three non-small cell lung cancer (NSCLC) cells (H1299, H520, H460) and one small cell lung cancer (SCLC) cell (H446) were treated with PSI for the first time. PSI significantly induced cell cycle arrest at the G2/M phase and mitochondrial-related apoptosis NSCLC cells but not SCLC cells. Additionally, PSI reduced phosphorylation of AKT in NSCLC and ERK in SCLC in general. Interestingly, we observed that PSI influenced different signaling pathways among the four kinds of lung cancer cells. After PSI treatment, p38 MAPK and ERK activation were observed in H1299, while p38 MAPK increased and JNK decreased in H520. On the contrary, we found JNK activation in H460 cells with PSI. However, PSI upregulated the AKT activity and inhibited the JNK expression in H446 cells. The results indicate that PSI exhibits the cytotoxicity in different pathways depending on the cancer types.
    Mots-clés : GOBS, POLE 3.


  • A. Martin, A. Arda, J. Désiré, A. Martin-Mingot, N. Probst, P. Sinaÿ, J. Jiménez-Barbero, S. Thibaudeau, et Y. Blériot, « Catching elusive glycosyl cations in a condensed phase with HF/SbF5 superacid », Nature Chemistry, vol. 8, nᵒ 2, p. 186-191.
    Résumé : Glycosyl cations are universally accepted key ionic intermediates in the mechanism of glycosylation, the reaction that covalently links carbohydrates to other molecules. These ions have remained hypothetical species so far because of their extremely short life in organic media as a consequence of their very high reactivity. Here, we report the use of liquid hydrofluoric acid–antimony pentafluoride (HF/SbF5) superacid to generate and stabilize the glycosyl cations derived from peracetylated 2-deoxy and 2-bromoglucopyranose in a condensed phase. Their persistence in this superacid medium allows their three-dimensional structure to be studied by NMR, aided by complementary computations. Their deuteration further confirms the impact of the structure of the glycosyl cation on the stereochemical outcome of its trapping.
    Mots-clés : Carbohydrate chemistry, GOBS, POLE 3, Structure elucidation.


  • M. Ménand, M. Sollogoub, B. Boitrel, et S. Le Gac, « Hexaphyrin–Cyclodextrin Hybrids: A Nest for Switchable Aromaticity, Asymmetric Confinement, and Isomorphic Fluxionality », Angewandte Chemie International Edition, vol. 55, nᵒ 1, p. 297-301.
    Résumé : Conformational control over the highly flexible π-conjugated system of expanded porphyrins is a key step toward the fundamental understanding of aromaticity and for the development of molecular electronics. We have synthesized unprecedented hexaphyrin–cyclodextrin (HCD) capped hybrids in which the hexaphyrin part is constrained in a planar rectangular conformation in either a 26 or a 28 π-electron oxidation state ([26]/[28]HCD). These structures display strong aromaticity and antiaromaticity, respectively, exhibit markedly different chiroptical properties, and are interconvertible upon the addition of DDQ or NaBH(OAc)3, thus affording a rare switchable aromatic–antiaromatic system with a free-base expanded porphyrin. Conformational analysis revealed discrimination of the two coordination sites of the hexaphyrin, one of which was coupled to a confined asymmetric environment, and fluxional behavior consisting of apparent rotation of the hexaphyrin cap through a shape-shifting mechanism.
    Mots-clés : aromaticity, conformation analysis, Cyclodextrins, degenerate equilibria, GOBS, POLE 3, porphyrinoids.


  • Y. Nie, M. Zhong, Z. Jiang, J. Sun, Y. Gao, F. Ding, H. Li, Y. Zhang, et X. He, « Synthesis and potential anticonvulsant activity of new aryl sulfonyl semicarbazide derivatives », Medicinal Chemistry Research, vol. 25, nᵒ 7, p. 1425-1432.
    Résumé : In the present study on the development of new anticonvulsants, twelve new aryl sulfonyl semicarbazide derivatives were synthesized and tested for anticonvulsant activity using maximal electroshock (MES), subcutaneous pentylenetetrazole screens. Their neurotoxicity was determined by the rotorod test. The most active compound 5i showed the MES-induced seizures with ED50 value of 7.3 mg/kg and TD50 value of 402.3 mg/kg after intraperitoneally injection to mice, which provided compound 5i with a protective index (TD50/ED50) of 55.1 in the MES test.
    Mots-clés : GOBS, POLE 3.


  • S. Roland, X. Ling, et M. - P. Pileni, « N-Heterocyclic Carbene Ligands for Au Nanocrystal Stabilization and Three-Dimensional Self-Assembly », Langmuir, vol. 32, nᵒ 31, p. 7683-7696.
    Résumé : N-Heterocyclic carbenes (NHCs) have emerged as a new class of ligands for materials chemistry that appears particularly relevant for the stabilization and functionalization of metal nanoparticles (NPs). The particular properties and high synthetic flexibility of NHCs make them highly attractive tools for the development of new (nano)materials and the fundamental study of their properties. The relationships between the NHC structure and NP structure/properties, including physical, biological, and self-assembly properties, remain largely unknown. In the past decade, many efforts have been made to gain more fundamental understanding in this area. In this feature article, we present our contribution in this field focusing on the formation of NHC-coated Au nanocrystals (NCs), their stability, and their ability to self-assemble into 3D crystalline structures called supracrystals. First, the formation of NHC-stabilized Au NCs is discussed by comparing different NHC structures, NHC-based Au precursors, and synthesis methods. This study shows the major role of the NHC structure in obtaining both stable NHC-coated Au NCs and narrow size distributions. In a second part, a comparative study of the oxygen resistance of NHC- and thiol-coated NCs is presented, demonstrating the enhanced stability of NHC-coated Au NCs to oxygen-based treatments. Finally, the self-assembly of NHC-coated Au NCs into 3D Au superlattices is presented. The formation of large organized domains of several micrometers is described from the design of NHCs tailored with long alkyl chains. In these different contexts, efforts have been made to gain a more in-depth understanding of the behavior of NHC ligands at the surface of NCs. These results show that the NHC-based approach to nanomaterials has many assets for opening a new research area in the supracrystal world.
    Mots-clés : GOBS, POLE 3.


  • Y. - O. Teng, H. - Y. Zhao, J. Wang, H. Liu, M. - L. Gao, Y. Zhou, K. - L. Han, Z. - C. Fan, Y. - M. Zhang, H. Sun, et P. Yu, « Synthesis and anti-cancer activity evaluation of 5-(2-carboxyethenyl)-isatin derivatives », European Journal of Medicinal Chemistry, vol. 112, p. 145-156.
    Résumé : A series of novel di- or trisubstituted isatin derivatives were designed and synthesized in 5–6 steps in 25–45% overall yields. Their structures were confirmed by 1H NMR and 13C NMR as well as LC-MS. The anticancer activity of the fourty-three new isatin derivatives against human T lymphocyte cells Jurkat was evaluated by MTT assay in vitro. SAR study suggested that the combination of 1-benzyl and 5-[trans-2-(methoxycarbonyl)ethen-1-yl] substitution greatly enhanced their cytotoxic activity. Among them, compound 2h was shown to have a significant cytotoxic activity with an IC50 value of 0.03 μM, more than 330-fold higher than that of it's mother molecule isatin. Investigation of the cell morphology changes and annexin-V/PI staining study demonstrated that compound 2h inhibited the proliferation of Jurkat cells by inducing apoptosis. Since compound 2h induced the dissipation of mitochondrial membrane potential and the activation of caspase-3, it was obvious that compound 2h inhibited the proliferation of Jurkat cells through the mitochondrial apoptotic pathway. Other than this, compound 2h exerted inhibition effect to many other tumor cells and only showed weak cytotoxic to human normal cells suggesting that compound 2h possessed a broad range of anticancer spectrum and high safety to normal cells.
    Mots-clés : Anti-tumor agents, Apoptosis, GOBS, Isatin derivatives, Jurkat cells, POLE 3, proliferation.

  • H. Wang, R. Xu, Y. Shi, L. Si, P. Jiao, Z. Fan, X. Han, X. Wu, X. Zhou, F. Yu, Y. Zhang, L. Zhang, L. Zhang, D. Zhou, et S. Xiao, « Design, synthesis and biological evaluation of novel L-ascorbic acid-conjugated pentacyclic triterpene derivatives as potential influenza virus entry inhibitors », European Journal of Medicinal Chemistry, vol. 110, p. 376-388.
    Résumé : Since the influenza viruses can rapidly evolve, it is urgently required to develop novel anti-influenza agents possessing a novel mechanism of action. In our previous study, two pentacyclic triterpene derivatives (Q8 and Y3) have been found to have anti-influenza virus entry activities. Keeping the potential synergy of biological activity of pentacyclic triterpenes and l-ascorbic acid in mind, we synthesized a series of novel l-ascorbic acid-conjugated pentacyclic triterpene derivatives (18-26, 29-31, 35-40 and 42-43). Moreover, we evaluated these novel compounds for their anti-influenza activities against A/WSN/33 virus in MDCK cells. Among all evaluated compounds, the 2,3-O,O-dibenzyl-6-deoxy-l-ascorbic acid-betulinic acid conjugate (30) showed the most significant anti-influenza activity with an EC50 of 8.7 μM, and no cytotoxic effects on MDCK cells were observed. Time-of-addition assay indicated that compound 30 acted at an early stage of the influenza life cycle. Further analyses revealed that influenza virus-induced hemagglutination of chicken red blood cells was inhibited by treatment of compound 30, and the interaction between the influenza hemagglutinin (HA) and compound 30 was determined by surface plasmon resonance (SPR) with a dissociation constant of KD = 3.76 μM. Finally, silico docking studies indicated that compound 30 and its derivative 31 were able to occupy the binding pocket of HA for sialic acid receptor. Collectively, these results suggested that l-ascorbic acid-conjugated pentacyclic triterpenes were promising anti-influenza entry inhibitors, and HA protein associated with viral entry was a promising drug target.
    Mots-clés : Animals, antiviral agents, Ascorbic Acid, Dogs, Drug design, Entry inhibitor, GOBS, Hemagglutinin, Hemagglutinin Glycoproteins, Influenza Virus, humans, Influenza A Virus, H1N1 Subtype, Influenza virus, Influenza, Human, l-ascorbic acid, Madin Darby Canine Kidney Cells, Molecular Docking Simulation, Orthomyxoviridae Infections, Pentacyclic triterpene, pentacyclic triterpenes, POLE 3, Sialic acid receptor, Virus Internalization.

  • H. Wang, Y. Cui, R. Zou, Z. Cheng, W. Yao, Y. Mao, et Y. Zhang, « Synthesis of oligosaccharides using per-O-trimethylsilyl-glycosyl iodides as glycosyl donor », Carbohydrate Research, vol. 427, p. 1-5.
    Résumé : Trimethylsilyl (TMS) protecting group has been found to be very useful for the simultaneous protection of both the glycosyl donor- and the acceptor-substrates in oligosaccharide synthesis. Thus, while the per-O-trimethylsilylated glycosyl iodides served as the glycosyl donor, those bearing selectively exposed primary hydroxyl groups were found suitable as the glycosyl acceptor for the reaction. The cheap and commercially available trialkylamine, triethylamine was found to be an effective promoter for the glycosylation. Importantly, the reaction was α-stereospecific and gave the products in 58%-78% yields.
    Mots-clés : Glycosyl iodide, GOBS, POLE 3, triethylamine, Trimethylsilyl group, α-Glycosylation.

  • X. - T. Wang, Z. - Y. Zhu, L. Zhao, H. - Q. Sun, M. Meng, J. - Y. Zhang, et Y. - M. Zhang, « Structural characterization and inhibition on α-d-glucosidase activity of non-starch polysaccharides from Fagopyrum tartaricum », Carbohydrate Polymers, vol. 153, p. 679-685.
    Résumé : In the present study, the crude polysaccharide was extracted from Fagopyrum tartaricum and purified by Sephadex G-25 and G-75 column to produce a polysaccharide fraction termed TBP-II. Its average molecular weight was 26kDa. The structural characterization of TBP-II was investigated by gas chromatography, periodate oxidation-Smith degradation, Methylation and NMR. Congo red was applied to explore its advanced structures. The results revealed that chemical composition and structural characteristic of TBP-II was mainly consisted of galactose, arabinose, xylose and glucose with a molar ratio of 0.7:1:6.3:74.2. The backbone of TBP-II was composed of (1→4)-linked α-d-glucopyranosyl (Glcp), while the branches comprised of (1→3)-linked α-d-glucopyranosyl (Glcp), (1→6)-linked α-d-galactopyranosyl (Galp) and (1→2,4)-linked α-d-rhamnopyranosyl (Rhap). The structure of TBP-II was 1,3 and 1,6-branched-galactorhamnoglucan that had a linear backbone of (1→4)-linked α-d-glucopyranose (Glcp). Using Congo red assay showed that it was absent of triple helix structure. The α-d-glucosidase inhibitory activity of TBP-II was determined using acarbose as positive control. The result showed that the inhibition rate depended on the concentration of polysaccharides.
    Mots-clés : Acetic acid (PubChem CID: 176), Butanol (PubChem CID: 263), Characterization, Chloroform (PubChem CID: 6212), Dimethyl sulfoxide (PubChem CID: 679), Ethanol (PubChem CID: 702), Fagopyrum tartaricum, GOBS, POLE 3, Polysaccharide, Sodium hydroxide (PubChem CID:14798), Trifluoroacetic acid(PubChem CID: 6422), α-d-glucosidase.

  • S. Xiao, L. Si, Z. Tian, P. Jiao, Z. Fan, K. Meng, X. Zhou, H. Wang, R. Xu, X. Han, G. Fu, Y. Zhang, L. Zhang, et D. Zhou, « Pentacyclic triterpenes grafted on CD cores to interfere with influenza virus entry: A dramatic multivalent effect », Biomaterials, vol. 78, p. 74-85.
    Résumé : Multivalent effect plays an important role in biological processes, particularly in the specific recognition of virus with its host cell during the first step of infection. Here we report the synthesis of multivalent pentacyclic triterpene grafted on cyclodextrin core and potency of against influenza entry activity. Nine star-shaped compounds containing six, seven and eight pentacyclic triterpene pharmacophore on cyclodextrin scaffold were prepared by way of copper-catalyzed azide-alkyl cycloaddition reaction under microwave activation. Some of the multimers exhibited much potent antiviral activity against H1N1 virus (A/WSN/33), even equivalent or superior to oseltamivir. The most active compound 31, a heptavalent oleanolic acid-β-cyclodextrin conjugate, shows an up to 125-fold potency enhancement by its IC50 value over the corresponding monovalent conjugate and oleanolic acid, disclosing a clear multivalent effect. Further studies show that three compounds 31-33 exhibited broad spectrum inhibitory activity against other two human influenza A/JX/312 (H3N2) and A/HN/1222 (H3N2) viruses with the IC50 values at 2.47-14.90 μM. Most importantly, we found that compound 31, one of the best representative conjugate, binds tightly to the viral envelope hemagglutinin with a dissociation constant of KD = 2.08 μM, disrupting the interaction of hemagglutinin with the sialic acid receptor and thus the attachment of viruses to host cells. Our study might establish a strategy for the design of new pharmaceutical agents based on multivalency so as to block influenza virus entry into host cells.
    Mots-clés : Animals, Dogs, Entry inhibitor, GOBS, Hemagglutinin, Influenza A Virus, H1N1 Subtype, Influenza virus, Madin Darby Canine Kidney Cells, Membrane Fusion, Multivalent effect, Pentacyclic triterpene, POLE 3, Triterpenes.


  • S. Xiao, Q. Wang, L. Si, X. Zhou, Y. Zhang, L. Zhang, et D. Zhou, « Synthesis and biological evaluation of novel pentacyclic triterpene α-cyclodextrin conjugates as HCV entry inhibitors », European Journal of Medicinal Chemistry, vol. 124, p. 1-9.
    Résumé : Hepatitis C virus (HCV) entry is a key target for the treatment of chronic HCV infection. In our continuing efforts to identify novel potential anti-HCV entry inhibitors, a series of water-soluble triazole-bridged α-cyclodextrin-pentacyclic triterpene conjugates were easily synthesized with moderate to good yields. These novel compounds were fully identified and characterized by 1D and 2D NMR spectroscopy and ESI-HRMS. The anti-HCV entry activities were determined based on HCVpp/VSVGpp entry assays. The best results were found for compounds 15 and 18, which displayed the most promising anti-HCV entry activities with average IC50 values of 1.18 μM and 0.25 μM, respectively. In addition, the in vitro cytotoxicity activity of the two compounds against MDCK cells showed no toxicity at 100 μM. Five different binding assays were set up to identify the action mechanism. The results showed that the compounds exert their inhibitory activity at the post-binding step and subsequently prevent virus entry.
    Mots-clés : click chemistry, GOBS, HCV entry inhibitor, Pentacyclic triterpene, POLE 3, α-Cyclodextrin.

  • Y. Yang, J. He, Y. Suo, L. Lv, J. Wang, C. Huo, Z. Zheng, Z. Wang, J. Li, W. Sun, et Y. Zhang, « Anti-inflammatory effect of taurocholate on TNBS-induced ulcerative colitis in mice », Biomedicine & Pharmacotherapy = Biomedecine & Pharmacotherapie, vol. 81, p. 424-430.
    Résumé : Taurocholate is a natural conjugated bile acid. The aim of this study was to evaluate the anti-inflammatory effect of taurocholate in TNBS-induced ulcerative colitis in mice. The colitis were induced by rectal administration of TNBS. After 24h, the experimental animals were treated with sulfasalazine (SASP, 500mg/kg/day) and taurocholate (20, 40 and 60mg/kg) for 7 consecutive days. The anti-inflammatory effects of taurocholate for colitis were assessed by body weight, colonic weight and length, macroscopic scores, and histopathological examinations. In addition, the colonic tissue levels of myeloperoxidase (MPO) activity, interleukin (IL)-1β, interferon (IFN-γ) and tumour necrosis factor-α (TNF-α) were also determined to assess the effect of taurocholate. Compared with the model group, treatment with taurocholate (20, 40 and 60mg/kg) significantly inhibited the body weight loss, improved colonic weight and length, and decreased macroscopic and histopathological scores. Furthermore, the activity accumulation of MPO and the colonic tissue levels of IL-1β, IFN-γ and TNF-α were also decreased by administration of taurocholate. All the findings of this study suggested that taurocholate has the anti-inflammatory effect in ulcerative colitis in mice and indicated it as a good candidate to treat inflammatory bowel disease.
    Mots-clés : Anti-inflammatory effect, Cytokines, GOBS, POLE 3, Taurocholate, TNBS, Ulcerative colitis.

  • Y. Yang, J. He, Y. Suo, Z. Zheng, J. Wang, L. Lv, C. Huo, Z. Wang, J. Li, W. Sun, et Y. Zhang, « Tauroursodeoxycholate improves 2,4,6-trinitrobenzenesulfonic acid-induced experimental acute ulcerative colitis in mice », International Immunopharmacology, vol. 36, p. 271-276.
    Résumé : Ulcerative colitis is a chronic nonspecific inflammatory disease of unknown cause. The aim of this study was to evaluate the anti-inflammatory effect of tauroursodeoxycholate in 2, 4, 6-trinitrobenzenesulfonic acid-induced experimental colitis in mice. After the induction of colitis for 24h, the mice were administrated orally with tauroursodeoxycholate (20, 40 and 60mg/kg) and sulfasalazine (500mg/kg) by gavage for 7 consecutive days. The inhibition effects were evaluated by the body of weight change, survival rate, macroscopical and histological evaluations. Besides, myeloperoxidase (MPO) activity, interleukin (IL)-1β, interferon (IFN)-γ and tumour necrosis factor-α (TNF-α) in colon tissue were also determined by enzyme-linked immunosorbent assay. Treatment with different doses of tauroursodeoxycholate (20, 40 and 60mg/kg) significantly improved the body weight change, decreased the macroscopic and histopathological scores. Compared with the model group, the accumulation of MPO activity, the colonic tissue levels of IL-1β, IFN-γ and TNF-α were significantly reduced in the tauroursodeoxycholate treated groups. Moreover, tauroursodeoxycholate assuaged the symptoms of colitis. These results suggested that tauroursodeoxycholate has an anti-inflammatory effect in TNBS-induced ulcerative colitis in mice.
    Mots-clés : Cytokines, GOBS, POLE 3, Tauroursodeoxycholate, Trinitrobenzenesulfonic acid, Ulcerative colitis.

  • Y. Zhang, D. Lu, M. Sollogoub, et Y. Zhang, « Carbohydrate–carbohydrate interaction: from hypothesis to confirmation », in Carbohydrate Chemistry, p. 238-254.
    Résumé : Carbohydrates play important roles in a wide range of biological processes. Since the first hypothesis about carbohydrate–carbohydrate interaction (CCI) was proposed by Hakomori et al., an increasing interest has been placed on CCI, using a variety of techniques. Based on all these studies, Lewisx–Lewisx interaction (a typical CCI) has been now confirmed to be specific, homotypic, and mediated by the presence of divalent cations such as Ca2+. In this review, a detailed overview of the process from hypothesis to confirmation of carbohydrate–carbohydrate interaction is summarized.
    Mots-clés : GOBS, POLE 3.

  • Y. Zhou, H. - Y. Zhao, D. Jiang, L. - Y. Wang, C. Xiang, S. - P. Wen, Z. - C. Fan, Y. - M. Zhang, N. Guo, Y. - O. Teng, et P. Yu, « Low toxic and high soluble camptothecin derivative 2-47 effectively induces apoptosis of tumor cells in vitro », Biochemical and Biophysical Research Communications, vol. 472, nᵒ 3, p. 477-481.
    Résumé : The cytotoxic activity of camptothecin derivatives is so high that these compounds need to be further modified before their successful application as anti-cancer agents clinically. In this study, we reported the synthesis and biological evaluation of a novel camptothecin derivative called compound 2-47. The changes in structure did not reduce its activity to inhibit DNA topoisomerase I. Compound 2-47 induced apoptosis of many tumor cells including leukemia cells K562, Jurkat, HL-60, breast cancer cell BT-549, colon cancer cell HT-29 and liver cancer cell HepG2 with a half maximal inhibitory concentration (IC50) of 2- to 3-fold lower than HCPT as a control. In particular, 2-47 inhibited the proliferation of Jurkat cells with an IC50 of as low as 40 nM. By making use of Jurkat cell as a model, following treatment of Jurkat cells, compound 2-47 activated caspase-3 and PARP, resulting in a decreased Bcl-2/Bax ratio. These data showed that compound 2-47 induces Jurkat cell death through the mitochondrial apoptotic pathway. In addition, compound 2-47 showed a decreased cytotoxic activity against normal cells and an improved solubility in low-polar solvent. For example, compound 2-47 solutes in CHCl3 130-fold higher than HCPT. Taken together, our data demonstrated that camptothecin derivative 2-47 notably inhibits the tumor cell proliferation through mitochondrial-mediated apoptosis in vitro.
    Mots-clés : Apoptosis, camptothecin, Camptothecin derivatives, Cell Line, Tumor, DNA topoisomerase I, Dose-Response Relationship, Drug, Drug design, GOBS, humans, Neoplasms, Experimental, POLE 3, Solubility, Treatment Outcome.

  • X. Zhu, M. Sollogoub, et Y. Zhang, « Biological applications of hydrophilic C60 derivatives (hC60s)- a structural perspective », European Journal of Medicinal Chemistry, vol. 115, p. 438-452.
    Résumé : Reactive oxygen species (ROS) generation and radical scavenging are dual properties of hydrophilic C60 derivatives (hC60s). hC60s eliminate radicals in dark, while they produce reactive oxygen species (ROS) in the presence of irradiation and oxygen. Compared to the pristine C60 suspension, the aqueous solution of hC60s is easier to handle in vivo. hC60s are diverse and could be placed into two general categories: covalently modified C60 derivatives and pristine C60 solubilized non-covalently by macromolecules. In order to present in detail, the above categories are broken down into 8 parts: C60(OH)n, C60 with carboxylic acid, C60 with quaternary ammonium salts, C60 with peptide, C60 containing sugar, C60 modified covalently or non-covalently solubilized by cyclodextrins (CDs), pristine C60 delivered by liposomes, functionalized C60-polymer and pristine C60 solubilized by polymer. Each hC60 shows the propensity to be ROS producer or radical scavenger. This preference is dependent on hC60s structures. For example, major application of C60(OH)n is radical scavenger, while pristine C60/γ-CD complex usually serves as ROS producer. In addition, the electron acceptability and innate hydrophobic surface confer hC60s with O2 uptake inhibition, HIV inhibition and membrane permeability. In this review, we summarize the preparation methods and biological applications of hC60s according to the structures.
    Mots-clés : Biological applications, GOBS, Hydrophilic C(60) derivatives, POLE 3, Radical scavenger, ROS generation.


  • Z. - Y. Zhu, L. Chen, F. Liu, L. - J. Chen, M. Meng, H. - Q. Sun, et Y. - M. Zhang, « Preparation and activity evaluation of chrysin-β-d-galactopyranoside », Archives of Pharmacal Research, vol. 39, nᵒ 10, p. 1433-1440.
    Résumé : Chrysin-β-d-galactopyranoside was efficiently synthesized, evaluated for its inhibitory activities against H22 cell lines compared with chrysin, the scavenging of hydroxyl radical, DPPH radical and superoxide anion, inhibitory effect against bacteria and fungi. The structures of all compounds were fully characterized by spectroscopic data (NMR, MS). The anti-tumor, antioxidant and antimicrobial activities of chrysin-β-d-galactopyranoside were proved to be enhanced significantly compared with chrysin.
    Mots-clés : GOBS, POLE 3.

  • Z. - Y. Zhu, D. Cui, H. Gao, F. - Y. Dong, X. -cui Liu, F. Liu, L. Chen, et Y. -min Zhang, « Efficient synthesis and activity of beneficial intestinal flora of two lactulose-derived oligosaccharides », European Journal of Medicinal Chemistry, vol. 114, p. 8-13.
    Résumé : Lactulose is considered as a prebiotic because it promotes the intestinal proliferation of Lactobacillus acidophilus which is added to various milk products. Moreover, lactulose is used in pharmaceuticals as a gentle laxative and to treat hyperammonemia. This study was aimed at the total synthesis of two Lactulose-derived oligosaccharides: one is 3-O-β-d-galactopyranosyl-d-fructose, d-fructose and β-d-galactose bounded together with β-1,3-glycosidic bound, the other is 1-O-β-d-galactopyranosyl-d-fructose, d-fructose and β-d-galactose bounded together with β-1,1-glycosidic bound, which were accomplished in seven steps from d-fructose and β-d-galactose and every step of yield above 75%. This synthetic route provided a practical and effective synthetic strategy for galactooligosaccharides, starting from commercially available monosaccharides. Then we evaluated on their prebiotic properties in the search for potential agents of regulating and improving the intestinal flora of human. The result showed that the prebiotic properties of Lactulose-derived oligosaccharides was much better than Lactulose. Among them, 3-O-β-d-galactopyranosyl-d-fructose displayed the most potent activity of proliferation of L. acidophilus.
    Mots-clés : GOBS, Lactobacillus acidophilus, Lactulose, Lactulose-derived oligosaccharides, POLE 3, Prebiotics.

  • Z. - Y. Zhu, F. Dong, X. Liu, Q. Lv, null YingYang, F. Liu, L. Chen, T. Wang, Z. Wang, et Y. Zhang, « Effects of extraction methods on the yield, chemical structure and anti-tumor activity of polysaccharides from Cordyceps gunnii mycelia », Carbohydrate Polymers, vol. 140, p. 461-471.
    Résumé : This study was to investigate the effects of different extraction methods on the yield, chemical structure and antitumor activity of polysaccharides from Cordyceps gunnii (C. gunnii) mycelia. Five extraction methods were used to extract crude polysaccharides (CPS), which include room-temperature water extraction (RWE), hot-water extraction (HWE), microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE) and cellulase-assisted extraction (CAE). Then Sephadex G-100 was used for purification of CPS. As a result, the antitumor activities of CPS and PPS on S180 cells were evaluated. Five CPS and purified polysaccharides (PPS) were obtained. The yield of CPS by microwave-assisted extraction (CPSMAE) was the highest and its anti-tumor activity was the best and its macromolecular polysaccharide (3000-1000kDa) ratio was the largest. The PPS had the same monosaccharide composition, but their obvious difference was in the antitumor activity and the physicochemical characteristics, such as intrinsic viscosity, specific rotation, scanning electron microscopy and circular dichroism spectra.
    Mots-clés : Acetic acid (PubChem CID: 176), Acetic anhydride (PubChem CID: 7918), Antitumor activity, Cellulase (PubChem CID: 3084041), Chemical structure, Chloroform (PubChem CID: 6212), Cordyceps gunnii, Dimethylsulfoxide (PubChem CID: 21912085), Ethanol (PubChem CID: 702), Extraction method, GOBS, Methanol (PubChem CID: 887), N-butyl alcohol (PubChem CID: 263), POLE 3, Polysaccharide, Pyridine (PubChem CID: 1049), Trifluoroacetic acid (PubChem CID: 6422).
  • Z. - Y. Zhu, Y. Li, H. - Q. Sun, L. - J. Chen, Y. - L. Tang, X. - C. Liu, et Y. - M. Zhang, « Screening of Cordyceps Strains and Optimization of Its Solid-State Fermentation Conditions on Bioconversion of Astragalus Residue », Cellulose Chemistry and Technology, vol. 50, nᵒ 2, p. 257-263.
    Résumé : The Astragalus residue is produced after the extraction of Astragalus polysaccharides (APS). In Astragalus residue, the main ingredient is crude fiber. The crude fiber is considered to be the main source for green chemicals, bio-fuels and bio-based products. In this study, we used five kinds of Cordyceps as fermentation strains and Astragalus residue as fermentation substrate for solid-state fermentation. Crude fiber degradation rate after fermentation was considered as the main indicator. The mannitol content and soluble sugar content of the fermentation product were used as secondary indicators. The experiments were carried out by screening the solid-state fermentation strains, optimizing the solid-state fermentation conditions and studying the pilot-scale cultivation of solid-state fermentation. From the results of screening the solid-state fermentation strains, we selected the Paecilomyces bainier strain for further investigation. The fermentation conditions were optimized with four single factors, including fermentation time, solid fermentation inoculum size, pH value of solid medium and fermentation substrate thickness. The single-factor tests revealed that the optimum conditions were the following: fermentation time of 25 days, fermentation substrate pH of the initial value, inoculum of 20% and fermentation substrate thickness of 1.0 cm.
    Mots-clés : Astragalus residue, Cordyceps Paecilomyces sinensis, GOBS, POLE 3, solid-state fermentation.


  • Z. - Y. Zhu, F. Liu, H. Gao, H. Sun, M. Meng, et Y. - M. Zhang, « Synthesis, characterization and antioxidant activity of selenium polysaccharide from Cordyceps militaris », International Journal of Biological Macromolecules, vol. 93, Part A, p. 1090-1099.
    Résumé : A purified selenium-containing derivatives of Cordyceps militaris polysaccharide synthesized using H2SeO3/HNO3 and BaCl2 as a catalyst was investigated in this paper. The reaction condition was optimized by selecting different reaction temperature and period. Afterward, the one with the highest Se content was purified by ultra-filtration device with a molecular cut off size of 10KDa. Followed by its structural characterizations. Results of IFR and 13C NMR spectroscopy indicated that C-6 substitution was predominant in selenized polysaccharide. The modified polysaccharide with molecular weight of 1998 KDa was mainly consisted of mannose, glucose and galactose in the mole ratios of with the mole ratios of 1:28.63:1.41. Thermogravimetric and morphological analyses of the samples were carried out by AFS, SEM and AFM. In addition, the in vitro antioxidant results suggested that selenium-containing polysaccharide should be applied as a novel selenium source in dietary supplements, with potent antioxidant properties.
    Mots-clés : Cordyceps militaris, GOBS, POLE 3, polysaccharides, Selenize, structure.

  • Z. - Y. Zhu, X. - C. Liu, F. - Y. Dong, M. - Z. Guo, X. - T. Wang, Z. Wang, et Y. - M. Zhang, « Influence of fermentation conditions on polysaccharide production and the activities of enzymes involved in the polysaccharide synthesis of Cordyceps militaris », Applied Microbiology and Biotechnology, vol. 100, nᵒ 9, p. 3909-3921.
    Résumé : The influence of different fermentation conditions on intracellular polysaccharide (IPS) production and activities of the phosphoglucomutase (PGM), UDPG-pyrophosphorylase (UGP), phosphoglucose isomerase (PGI), UDPG-dehydrogenase (UGD), and glucokinase (GK) implicated in metabolite synthesis in Cordyceps militaris was evaluated. The highest IPS production (327.57 ± 6.27 mg/100 mL) was obtained when the strain was grown in the optimal medium containing glucose (40 g · L(-1)), beef extract (10 g · L(-1)), and CaCO3 (0.5 g · L(-1)), and the initial pH and temperature were 7 and 25 °C, respectively. The activities of PGM, UGP, and PGI were proved to be influenced by the fermentation conditions. A strong correlation between the activities of these enzymes and the production of IPS was found. The transcription level of the pgm gene (encoding PGM) was 1.049 times and 1.467 times compared to the ugp gene and pgi gene (encoding UGP and PGI), respectively, in the optimal culture medium. This result indicated that PGM might be the highly key enzyme to regulate the biosynthesis of IPS of C. militaris in a liquid-submerged culture. Our study might be helpful for further research on the pathway of polysaccharide biosynthesis aimed to improve the IPS production of C. militaris.
    Mots-clés : biosynthesis, Cordyceps militaris, Enzyme activity, GOBS, Intracellular polysaccharides, POLE 3.
  • >
    Z. - Y. Zhu, X. - C. Liu, X. - N. Fang, H. - Q. Sun, X. - Y. Yang, et Y. - M. Zhang, « Structural characterization and anti-tumor activity of polysaccharide produced by Hirsutella sinensis », International Journal of Biological Macromolecules, vol. 82, p. 959-966.
    Résumé : HSP-III, a novel homogeneous polysaccharide with 513.89 kDa molecular weight, was fractionated from submerged cultures of Hirsutella sinensis by Sevag and chromatography on Sephadex G-100 column. The total sugar content of HSP-III was amounted to 89.87%. Based on the results of high performance gel permeation chromatogram (HPGPC), FT-IR, NMR spectroscopy, GC, periodate oxidation-smith degradation and methylation analysis, it showed that HSP-III was mainly composed of mannose and galactose, and a small amount of rhamnose, arabinose, xylose, and glucose. The molar ratio of Rha:Ara:Xyl:Man:Glu:Gal was 1.00:2.44:13.11:74.13:13.80:54.39. The main chain of HSP-III was majorly composed of (1→3) glucose. The tumor inhibition ratio on H22 cell was 79.04% at 100 μg/mL of HSP-III.
    Mots-clés : Anti-tumor activity, Antineoplastic Agents, Ascomycota, Cell Line, Tumor, Cell Survival, Fungal Polysaccharides, GOBS, humans, Magnetic Resonance Spectroscopy, Methylation, Molecular Weight, Periodic Acid, POLE 3, Polysaccharide, Spectroscopy, Fourier Transform Infrared, structure, Structure-Activity Relationship.


  • Z. - Y. Zhu, Y. Luo, G. - L. Dong, Y. - Y. Ren, L. - J. Chen, M. - Z. Guo, X. - T. Wang, X. - Y. Yang, et Y. Zhang, « Effects of the ultra-high pressure on structure and α-glucosidase inhibition of polysaccharide from Astragalus », International Journal of Biological Macromolecules, vol. 87, p. 570-576.
    Résumé : A novel homogeneous polysaccharide fraction (APS) was extracted from Astragalus by hot water and purified by Sephadex G-100 and G-75 column. Its molecular weight was 693 kDa. APS and APS with...
    Mots-clés : GOBS, POLE 3.


  • Z. - Y. Zhu, Y. Luo, Y. Liu, X. - T. Wang, F. Liu, M. - Z. Guo, Z. Wang, A. - J. Liu, et Y. - M. Zhang, « Inclusion of chrysin in β-cyclodextrin and its biological activities », Journal of Drug Delivery Science and Technology, vol. 31, p. 176-186.
    Résumé : Chrysin is a plant flavone that possesses some significant biological activities. β-Cyclodextrin (β-CD) due to its property of encapsulating molecules that are hydrophobic in nature is widely applied as drug delivery vehicle. The paper presents the preparation, characterization and properties of chrysin-β-cyclodextrin inclusion complex. The stoichiometry of the inclusion complex has been established to be 1:3 (chrysin to β-cyclodextrin), with the inclusion rate of 90.5 ± 2.63 at 55 °C. The process of inclusion not only increased the solubility of chrysin but also its antioxidant potential, antimicrobial activity and anti-tumor activity.
    Mots-clés : Biological activities, Chrysin, GOBS, inclusion complex, POLE 3, Water solubility, β-Cyclodextrin.

  • Z. - Y. Zhu, M. Meng, H. Sun, Y. Li, Y. - Y. Ren, et Y. Zhang, « Immunostimulatory activity of glycopeptides from Paecilomyces sinensis under normal and cyclophosphamide induced immunosuppressive conditions in mice models », Food & Function, vol. 7, nᵒ 8, p. 3566-3576.
    Résumé : The present study was designed to evaluate immune-modulating effects of the glycopeptide from Paecilomyces sinensis (CPS-II) by using mouse peritoneal macrophage and cytoxan (CTX) induced immunosuppression models. Our results from phagocytotic and mononuclear phagocytic system function assays showed that CPS-II stimulated phagocytosis of the phagocytes. A splenocyte proliferation assay showed that CPS-II acted to combine Concanavalin A (ConA) or lipopolysaccharides (LPS) in splenocyte proliferation. The results demonstrated that CPS-II increased the indices of the thymus and spleen. Hematological and histopathological analysis revealed the protective effect of CPS-II against CTX induced immunosuppression. CPS-II also significantly increased the expression of CD4(+) and CD8(+) splenic T lymphocytes, which were suppressed by CTX in peripheral blood. The expressions of serum cytokines related to immune function, including TNF-α, IL-6, and IFN-γ, were up-regulated in a dose-dependent manner. The expression of the transcription factor NF-κB in the spleen was enhanced after CPS-II-treatment. In conclusion, our results indicated that CPS-II was involved in immunostimulatory actions leading to its modulatory effects on immunosuppression, and one possible mechanism of action was to activate NF-κB.
    Mots-clés : GOBS, POLE 3.

  • Z. - Y. Zhu, M. Meng, H. Sun, Y. Li, N. Yu, et Y. - M. Zhang, « Structural analysis and immunostimulatory activity of glycopeptides from Paecilomyces sinensis », Food & Function, vol. 7, nᵒ 3, p. 1593-1600.
    Résumé : The parasitic fungus, Paecilomyces sinensis, is used to produce Cordyceps materials as a succedaneum of natural Cordyceps sinensis (C. sinensis) in China. In this work, a glycopeptide (CPS-II) was isolated and purified from Paecilomyces sinensis. The result of HPLC indicated that CPS-II was a glycopeptide. The estimated average molecular weight of CPS-II was 2 × 10(6) Da. FTIR, methylation, periodate oxidation, Smith degradation, (1)H NMR, (13)C NMR and CD were used for its structural analysis. The glycopeptide CPS-II was mainly composed of (1 → 3), (1 → 4) connected glucose and galactose as the backbone, there are (1 → 2,3,6) connected glucose, (1 → 3,6) connected mannose, and (1 → 6) connected galactose. Cell proliferation assay and morphological observations indicated that in a certain range of concentrations and time, CPS-II can significantly improve the proliferation activity of RAW264.7 cells.
    Mots-clés : GOBS, POLE 3.


  • Z. - Y. Zhu, Z. -qian Wang, F. Liu, X. - C. Liu, L. - J. Chen, X. - R. Ge, A. - J. Liu, et Y. - M. Zhang, « Synthesis and Antitumor Activity of a New Ergosterol Derivative », Chemistry of Natural Compounds, vol. 52, nᵒ 2, p. 252-255.
    Résumé : Ergosterol-3-O-(β-D-galactopyranosyl-(1→4)-β-D-glucopyranoside) was efficiently synthesized and evaluated for its inhibitory activities against S180 cell lines compared with ergosterol. The structures of all synthesized compounds were fully characterized by spectroscopic data (NMR, MS). The antitumor activity of the new derivative was significantly enhanced compared with ergosterol.
    Mots-clés : GOBS, POLE 3.


  • Z. Zy, L. Xc, T. Yl, D. Fy, S. Hq, C. L, et Z. Ym, « Effects of cultural medium on the formation and antitumor activity of polysaccharides by Cordyceps gunnii. », Journal of bioscience and bioengineering, vol. 122, nᵒ 4, p. 494-498.
    Résumé : Abstract: The effects of culture medium composition (i.e., carbon and nitrogen sources) on the growth of mycelia, molecular weight distribution and...
    Mots-clés : GOBS, POLE 3.

2015



  • I. Azcarate, Z. Huo, R. Farha, M. Goldmann, H. Xu, B. Hasenknopf, E. Lacôte, et L. Ruhlmann, « Generation of Photocurrent by Visible-Light Irradiation of Conjugated Dawson Polyoxophosphovanadotungstate–Porphyrin Copolymers », Chemistry – A European Journal, vol. 21, nᵒ 22, p. 8271-8280.
    Résumé : Four hybrid polyoxometalate–porphyrin copolymer films were obtained by the electrooxidation of zinc octaethylporphyrin in the presence of four different Dawson-type polyoxometalates bearing two pyridyl groups (POM(py)2) with various spacers. The POM monomers were designed around 1,3,5-trisubstituted benzene rings. Two of the substituents of the benzene ring are linked to the pyridyl groups, and the third is connected to the POM subunit. The four monomers vary in the relative positions of the nitrogen atoms of the pyridine rings or in the distance from the carbonyl group. The monomers were fully characterized by 1H, 31P, and 13C NMR spectroscopy, electrospray mass spectrometry, IR and UV/Vis spectroscopy, and electrochemistry. The copolymers were characterized by UV/Vis spectroscopy, X-ray photoelectron spectroscopy, electrochemistry, and AFM. Their photovoltaic performance under visible light irradiation was investigated by photocurrent transient measurements under visible illumination.
    Mots-clés : copolymerization, GOBS, organic–inorganic hybrid composites, POLE 3, Polyoxometalates, porphyrinoids, thin films.

  • Y. Cui, Z. Li, Z. Cheng, C. Xia, et Y. Zhang, « 4,5-cis unsaturated α-GalCer analogues distinctly lead to CD1d-mediated Th1-biased NKT cell responses », Chemical Research in Toxicology, vol. 28, nᵒ 6, p. 1209-1215.
    Résumé : The total synthesis of 4,5-cis unsaturated α-GalCer analogues was achieved, and their immune-response altering activity was assessed in vitro as well as in vivo in mice. Using glycosyl iodide as a glycosyl donor, construction of the sphingosine unit was shortened by four steps and single α-stereoselectivity was achieved in good yield (67%). With regard to the therapeutic use of α-GalCer, the novel analogues (1b and 1c) distinctly induced a Th1-biased cytokine response, avoiding induction of a contradictory response and overstimulation.
    Mots-clés : Animals, Antigens, CD1d, Cytokines, Enzyme-Linked Immunosorbent Assay, Galactosylceramides, GOBS, mice, Mice, Inbred C57BL, Molecular Structure, Natural Killer T-Cells, POLE 3, Stereoisomerism, Th1 Cells, Tumor Cells, Cultured.


  • A. M. Debela, S. Thorimbert, B. Hasenknopf, C. K. O'Sullivan, et M. Ortiz, « Electrochemical primer extension for the detection of single nucleotide polymorphisms in the cardiomyopathy associated MYH7 gene », Chemical Communications, vol. 52, nᵒ 4, p. 757-759.
    Résumé : We report the labelling of dideoxy nucleotides (ddNTPs) for use in electrochemical array based primer extension for the detection of single nucleotide polymorphisms (SNPs). The results confirm the extension of the immobilised primers for each of the four ddNTPs, representing a significant advance in achieving a cost-effective platform for screening of disease-specific SNPs.
    Mots-clés : CHEMBIO, GOBS, POLE 3.


  • A. M. Debela, M. Ortiz, V. Beni, S. Thorimbert, D. Lesage, R. B. Cole, C. K. O'Sullivan, et B. Hasenknopf, « Biofunctionalization of Polyoxometalates with DNA Primers, Their Use in the Polymerase Chain Reaction (PCR) and Electrochemical Detection of PCR Products », Chemistry – A European Journal, vol. 21, nᵒ 49, p. 17721-17727.
    Résumé : The bioconjugation of polyoxometalates (POMs), which are inorganic metal oxido clusters, to DNA strands to obtain functional labeled DNA primers and their potential use in electrochemical detection have been investigated. Activated monooxoacylated polyoxotungstates [SiW11O39{Sn(CH2)2CO}]8− and [P2W17O61{Sn(CH2)2CO}]6− have been used to link to a 5′-NH2 terminated 21-mer DNA forward primer through amide coupling. The functionalized primer was characterized by using a battery of techniques, including electrophoresis, mass spectrometry, as well as IR and Raman spectroscopy. The functionality of the POM-labeled primers was demonstrated through hybridization with a surface-immobilized probe. Finally, the labeled primers were successfully used in the polymerase chain reaction (PCR) and the PCR products were characterized by using electrophoresis.
    Mots-clés : CHEMBIO, CSOB, DNA, DNA Primers, Electrochemistry, GOBS, Nucleic Acid Hybridization, POLE 3, polymerase chain reaction, Polyoxometalates, Redox chemistry, Tungsten Compounds.


  • B. Doistau, J. - L. Cantin, L. - M. Chamoreau, V. Marvaud, B. Hasenknopf, et G. Vives, « Mechanical switching of magnetic interaction by tweezers-type complex », Chemical Communications, vol. 51, nᵒ 65, p. 12916-12919.
    Résumé : A control of the interaction between two spin centers was achieved by using a mechanical motion in a terpy(Cu–salphen)2 complex. Upon coordination a conformation change and switching from a paramagnetic to an antiferromagnetically coupled system was observed by EPR and SQUID measurements.
    Mots-clés : E-POM, GOBS, POLE 2, POLE 3, SUPRA.

  • B. Doistau, C. Rossi-Gendron, A. Tron, N. D. McClenaghan, L. - M. Chamoreau, B. Hasenknopf, et G. Vives, « Switchable platinum-based tweezers with Pt-Pt bonding and selective luminescence quenching », Dalton Transactions, vol. 44, nᵒ 18, p. 8543-8551.
    Résumé : Molecular tweezers incorporating peripheral platinum salphen complexes and a central chelating terpyridine group have been synthesized. The terpyridine can be switched upon metal binding between a free 'W' shaped form and a coordinated 'U' form. The crystallographic structure of the zinc-closed molecular tweezers was obtained and presented a strong pi-stacking between the Pt-salphen units associated with a Pt-Pt bond. The luminescence properties, notably in response to selected guest ions (Zn2+, Pb2+, Hg2+) and the resulting mechanical motion, have been investigated by UV-Vis and emission spectroscopy. While ion coordination to the terpy resulted in no significant changes in the luminescence, a selective intercalation of a second Hg2+ associated with a large differential quenching was observed.
    Mots-clés : alkynylplatinum(ii) terpyridine system, architectures, dot-m interactions, dynamic chemical-devices, emission, GOBS, metal-complexes, molecular tweezers, motion, POLE 3, pt(ii), stacking interactions.


  • M. Guitet, M. Ménand, et M. Sollogoub, « Cyclodextrins–Metal Hybrids », in Chemistry of Organo-Hybrids, B. Charleux, C. Copéret, et E. Lacôte, Éd. John Wiley & Sons, Inc., p. 349-394.
    Résumé : Cyclodextrins associated to metal centers or cyclodextrin–metal hybrids have been developed for a very long time mainly because this association was seen as potentially mimicking metallo-enzymes. To generate such mimics it is necessary to functionalize cyclodextrins with multiple functions; this chapter presents the most frequently used and recent poly-modifications. The chapter gives an overview of the different cyclodextrin-based metal complexes, where the metal is precisely placed with respect to the cavity. It focuses on polyfunctionalized cyclodextrins, first describing complexes using cyclodextrins as platforms, then those using the cavity as a receptor for the ligand of the metal, and finally those using cyclodextrin as a host for the metal. The chapter describes applications of such complexes to metallo-enzyme mimicry. One of the main methods used to characterize cyclodextrins is nuclear magnetic resonance (NMR). Other usual techniques like infrared spectroscopy and mass spectrometry are also frequently used to characterize cyclodextrins.
    Mots-clés : cyclodextrin–metal hybrids, GOBS, infrared spectroscopy, mass spectrometry, metallo-enzyme mimics, organic molecules, POLE 3, polyfunctionalized cyclodextrins.

  • K. Han, Y. Li, Y. Zhang, Y. Teng, Y. Ma, M. Wang, R. Wang, W. Xu, Q. Yao, Y. Zhang, H. Qin, H. Sun, et P. Yu, « Design, synthesis and docking study of novel tetracyclic oxindole derivatives as alpha-glucosidase inhibitors », Bioorganic & Medicinal Chemistry Letters, vol. 25, nᵒ 7, p. 1471-1475.
    Résumé : A series of novel tetracyclic oxindole derivatives were synthesized via tandem Suzuki coupling-Michael addition reaction catalyzed by palladium. Twenty derivatives were designed and synthesized in 6-8 steps in 8-20% overall yields. Their structures were confirmed by H-1, C-13 NMR and LC/MS. These compounds were evaluated for alpha-glucosidase inhibitory act

    ivity in vitro. Compounds 7c, 7d, 7e, 7g, 7h, and 7i exhibited IC50 values of 32.3, 12.1, 15.7, 29.0, 16.0, and 4.8 mu M, respectively, with potency all higher than that of the control standard acarbose (IC50 = 115.8 mu M). Molecular docking studies revealed the existence of potential hydrogen bonding and hydrophobic interaction between the enzyme and the active compound 7i. (C) 2015 Elsevier Ltd. All rights reserved.
    Mots-clés : Alkaloids, alpha-glucosidase inhibitors, anticancer agents, cells, Docking study, GOBS, identification, Phenanthridine derivatives, POLE 3, SAR study, Tetracyclic isatins, vitro cytotoxicity evaluation.


  • Z. Huo, I. Azcarate, R. Farha, M. Goldmann, H. Xu, B. Hasenknopf, E. Lacôte, et L. Ruhlmann, « Copolymeric films obtained by electropolymerization of porphyrins and dipyridyl-spacers including Dawson-type polyoxometalates », Journal of Solid State Electrochemistry, vol. 19, nᵒ 9, p. 2611-2621.
    Résumé : This paper reports the formation of hybrid polyoxometalate-porphyrin copolymeric films obtained by the electro-oxidation of zinc-β-octaethylporphyrin (ZnOEP) in the presence of a functionalized Dawson-type polyoxometalate bearing two pyridyl groups (POMdbme3,3, Py-POM-Py) which will be compared to the copolymer obtained from ZnOEP and a dipyridyl compound without POM (ibme3,3). The resulting film has been characterized by UV-visible absorption spectroscopy, X-ray photoelectron spectroscopy, and atomic force microscopy. Electrochemical quartz crystal microbalance was employed to investigate the poly-porphyrin-POMs deposition mass.Graphical Abstract
    Mots-clés : GOBS, POLE 3.


  • Z. Huo, D. Zang, S. Yang, R. Farha, M. Goldmann, B. Hasenknopf, H. Xu, et L. Ruhlmann, « Synthesis and characterization of Lindqvist-type polyoxometalate–porphyrin copolymers », Electrochimica Acta, vol. 179, p. 326-335.
    Résumé : Hybrid polyoxometalate-porphyrin copolymeric films were obtained by the electrooxidation of 5, 15-ditolyl porphyrin (H2T2P) and zinc-β-octaethylporphyrin (ZnOEP) in the presence of the Lindqvist-type polyoxovanadates TBA2[V6O13{(OCH2)3CNHCO(4-C5H4N)}2] (Py-POM-Py). The resulting films have been characterized by UV–visible absorption spectroscopy, X-ray photoelectron spectroscopy, atomic force microscopy and electrochemistry. Electrochemical quartz crystal microbalance was employed to investigate the copolymer mass.
    Mots-clés : copolymer, electropolymerization, EQCM, GOBS, POLE 3, Polyoxometalate, Porphyrin.


  • Y. Jagadeesh, A. T. Tran, B. Luo, N. Auberger, J. Désiré, S. Nakagawa, A. Kato, Y. Zhang, M. Sollogoub, et Y. Blériot, « γ-Aminoalcohol rearrangement applied to pentahydroxylated azepanes provides pyrrolidines epimeric to homoDMDP », Organic & Biomolecular Chemistry, vol. 13, nᵒ 11, p. 3446-3456.
    Résumé : A series of pentahydroxylated pyrrolidines, displaying five contiguous stereogenic centres and epimeric to α-glucosidase inhibitor homoDMDP, have been synthesized. The key step involves a γ-aminoalcohol rearrangement applied to polyhydroxylated azepanes. These five-membered iminosugars demonstrate micromolar inhibition of glycosidases.
    Mots-clés : 2,5-dideoxy-2,5-imino-d-mannitol dmdp, 4-methoxybenzylidene acetals, 7-membered iminocyclitols, alpha-mannosidase, concise synthesis, glycosidase inhibitors, GOBS, group strategy, mimicking monosaccharides, POLE 3, polyhydroxylated pyrrolidine, ring-closing metathesis.


  • J. Lesage de la Haye, A. Pontes da Costa, G. Pembouong, L. Ruhlmann, B. Hasenknopf, E. Lacôte, et J. Rieger, « Study of the temperature-induced aggregation of polyoxometalate-poly(N,N-diethylacrylamide) hybrids in water », Polymer, vol. 57, p. 173-182.
    Résumé : In this article, we study the temperature-induced phase transition of aqueous solutions of tailor-made Dawson polyoxometalate-poly(N,N-diethylacrylamide) hybrids (POM-PDEAAm) by means of differential scanning calorimetry, dynamic light scattering and cryo-TEM microscopy. Generally, the typical thermoresponsive aggregation of the PDEAAm in water was transferred to the hybrids. The organization of the compounds in solution below and above the transition temperature was studied, and precious insights in the aggregation mechanisms were obtained. The impact of the polymer chain-ends, the nature of the counterions of the negatively charged POM subunits and the weight fraction of the POM was elucidated, revealing a strong influence of the POM's counter-ions. Temperature and nature of the cations are thus two external factors that can be used to control the properties of the conjugates.
    Mots-clés : Cryo-TEM, DSC, GOBS, LCST, POLE 3.


  • J. Lesage de La Haye, J. - M. Guigner, E. Marceau, L. Ruhlmann, B. Hasenknopf, E. Lacôte, et J. Rieger, « Amphiphilic Polyoxometalates for the Controlled Synthesis of Hybrid Polystyrene Particles with Surface Reactivity », Chemistry – A European Journal, vol. 21, nᵒ 7, p. 2948-2953.
    Résumé : Amphiphilic organo-polyoxometalates (POMs) used in the radical emulsion polymerization of styrene allowed the preparation in aqueous medium of stable 50–100 nm polystyrene–POM composite latexes. Thanks to the presence of a trithiocarbonate group in the POM amphiphile, POMs could be covalently linked to the polymer particle surface. The chemical and catalytic integrity of the POMs was confirmed, and the POM-mediated surface photoactivity of the latexes was demonstrated by the spatially controlled nucleation of silver nanoparticles at the periphery of the composites.
    Mots-clés : amphiphiles, emulsion polymerization, GOBS, hybrid materials, photocatalysis, POLE 3, POLE 4, POLYMERES, Polyoxometalates.

  • X. Ling, S. Roland, et M. - P. Pileni, « Supracrystals of N-Heterocyclic Carbene-Coated Au Nanocrystals », Chemistry of Materials, vol. 27, nᵒ 2, p. 414-423.
    Résumé : Controlling the generation of organized 3D assemblies of individual nanocrystals, called supracrystals, as well as their properties, is an important challenge for the design of new materials in which the coating agent plays a major role. We present herein a new generation of structured fcc Au supracrystals made of N-heterocyclic carbene (NHC)-coated Au nanocrystals. The 3D assemblies were achieved by using benzimidazole-derived NHCs tailored with long alkyl chains at different positions. The average size of the nanocrystal precursors (4, 5, or 6 nm) and their ability to self-assemble were found to be dependent on the length, orientation, and number of alkyl chains on the NHC. Thick and large supracrystal domains were obtained from 5 nm Au nanocrystals coated with NHCs substituted by C14 alkyl chains on the nitrogen atoms. Here, the geometry of both the C-carbene-Au and N-C-alkyl bonds induces a specific orientation of the alkyl chains, different from that of alkylthiols, resulting in Au surface covering by the chains. However, the edge-to-edge distances in the supracrystals suggest that the supracrystals are stabilized by interdigitation of neighboring nanocrystals alkyl chains, whose terminal part must point outward with the appropriate geometry.
    Mots-clés : chemistry, co oxidation, colloids, GOBS, inorganic nanoparticles, Ligands, metal-complexes, POLE 3, ruthenium nanoparticles, self-assembled monolayers, superlattices, supported gold catalysts.

0 | 50 | 100 | 150 | 200

--- Exporter la sélection au format