Author: "Didier Dubreuil" - Searchworks@Jio Institute Digital Library Search Results

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133 results on '"Didier Dubreuil"'

1. An efficient and simple strategy toward the synthesis of highly functionalized compounds

Author: Momtez Jmai, Didier Dubreuil, Mohamed Lotfi Efrit, Jacques Lebreton, Virginie Blot, and Hedi M'rabet
Subjects: Inorganic Chemistry, Chemistry, Simple (abstract algebra), Organic Chemistry, Biochemistry, Combinatorial chemistry
Published: 2021

2. Quantix and Intrapix: test benches dedicated to quantum efficiency measurement and intra-pixel response of detectors from VIS to LWIR

Author: Thibault Pichon, Ayoub Bounab, Cyril Cervera, Cyrille Delisle, Sophie Derelle, Didier Dubreuil, Benoit Horeau, Eduard Huard, Christian Ketchazo, Vincent Moreau, Patrick Mulet, Michel Lortholary, Thierry Orduna, Léna Provost, Samuel Ronayette, Olivier Tellier, and Olivier Boulade
Published: 2022

3. Thorough investigation of non-volatile substances extractible from inner coatings of metallic cans and their occurrence in the canned vegetables

Author: Ronan Cariou, Matthieu Rivière, Sébastien Hutinet, Asmaa Tebbaa, Didier Dubreuil, Monique Mathé-Allainmat, Jacques Lebreton, Bruno Le Bizec, Arnaud Tessier, and Gaud Dervilly
Subjects: Environmental Engineering, Health, Toxicology and Mutagenesis, Polyesters, Vegetables, Food Packaging, Environmental Chemistry, Food Contamination, Pollution, Waste Management and Disposal
Abstract: Since the decline of the use of bisphenol A, the chemistry of the varnishes and coatings which are applied to the inner surfaces of metallic food contact materials is poorly documented. We hypothesised that can coatings are now diverse and bring forth various non-intentionally added substances (NIAS) to be described. Investigating complex components such as NIAS requires demanding non-targeted approaches. We investigated the coatings of 12 vegetable cans from the French market. More than 125 substances were pinpointed, among them 84 oligoester combinations from 8 diols and 4 diacids. Thus, oligoesters were the dominant family. Additives such as epoxidised soybean oil, bisphenol A diglycidyl ether and benzoguanamine derivatives and phenol-formaldehyde oligomers were also identified. A software for exploring databases of theoretical combinations of polyester and phenol-formaldehyde resin components (NIAS-db 1.0) was made available. The stepwise organic synthesis of native and deuterated combinations of neopentyl glycol and isophthalic acid (4 and 8 units, linear and cyclic) enabled a higher confidence level and monitoring in vegetable extracts. Migration of oligoesters averaged 330 µg/kg in the drained vegetables (43-1600 µg/kg). This study sheds light on the need to fulfil a proper risk assessment on this NIAS family (exposure and hazard characterisation).
Published: 2022

4. Synthesis and biological evaluation of 3-amino-, 3-alkoxy- and 3-aryloxy-6-(hetero)arylpyridazines as potent antitumor agents

Author: Eric Léonel, Morgane Rousselle, Didier Dubreuil, Gervaise Loirand, Florian Dilasser, Rémy Le Guével, Erwan Le Gall, Muriel Pipelier, Vincent Sauzeau, Stéphane Sengmany, Jacques Lebreton, Mathilde Sitter, Thierry Martens, Institut de Chimie et des Matériaux Paris-Est (ICMPE), Institut de Chimie du CNRS (INC)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), unité de recherche de l'institut du thorax UMR1087 UMR6291 (ITX), Université de Nantes - UFR de Médecine et des Techniques Médicales (UFR MEDECINE), Université de Nantes (UN)-Université de Nantes (UN)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Synthèse Organique (Hétérochimie organique, organoéléments et matériaux) (LSOHOOM), Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS), Plate-forme ImPACcell (ImPACcell), Structure Fédérative de Recherche en Biologie et Santé de Rennes ( Biosit : Biologie - Santé - Innovation Technologique ), CNRS, Universite Paris-Est Creteil, Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université de Nantes - UFR de Médecine et des Techniques Médicales (UFR MEDECINE), Université de Nantes (UN)-Université de Nantes (UN), Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), Unité de recherche de l'institut du thorax (ITX-lab), and Jonchère, Laurent
Subjects: Nickel catalysis, [CHIM.THER] Chemical Sciences/Medicinal Chemistry, Clinical Biochemistry, Pharmaceutical Science, Antineoplastic Agents, [CHIM.THER]Chemical Sciences/Medicinal Chemistry, Oncogenicity, Electrosynthesis, 01 natural sciences, Biochemistry, chemistry.chemical_compound, Cell Line, Tumor, Drug Discovery, Humans, Molecular Biology, ComputingMilieux_MISCELLANEOUS, Cell Proliferation, Biological evaluation, Arylpyridazines, Cytotoxic activity, [CHIM.ORGA]Chemical Sciences/Organic chemistry, 010405 organic chemistry, Chemistry, Aryl, Organic Chemistry, Combinatorial chemistry, In vitro, 0104 chemical sciences, 3. Good health, Pyridazines, 010404 medicinal & biomolecular chemistry, HaCaT, Alkoxy group, Molecular Medicine, Drug Screening Assays, Antitumor, Signal transduction
Abstract: International audience; Various 3-amino-, 3-aryloxy- and alkoxy-6-arylpyridazines have been synthesized by an electrochemical reductive cross-coupling between 3-amino-, 3-aryloxy- or 3-alkoxy-6-chloropyridazines and aryl or heteroaryl halides. In vitro antiproliferative activity of these products was evaluated against a representative panel of cancer cell lines (HuH7, CaCo-2, MDA-MB-231, HCT116, PC3, NCI-H727, HaCaT) and oncogenicity prevention of the more efficient derivatives was highlighted on human breast cancer cell line MDA-MB 468-Luc prior establishing their interaction with p44/42 and Akt-dependent signaling pathways.
Published: 2019

5. B-BOP, the SPICA Imaging Polarimeter

Author: Sylvain Martin, Marc Sauvage, Michel Berthé, Laurent Dussopt, S. Bounissou, Pierre-Antoine Frugier, J. Martignac, Didier Dubreuil, Marcos Chimeno, O. Gevin, Lionel Duband, A. Aliane, Jean-Yves Plesseria, Louis Rodriguez, Amala Demonti, V. Goudon, Benoit Marquet, François Visticot, Xavier de la Broïse, Jacques Delabrouille, Vincent Reveret, Javier Pérez, Eric Doumayrou, Camille Gennet, Josefina Torres Redondo, Obaïd Adami, X. F. Navick, H. Kaya, Albrecht Poglitsch, Cyrille Delisle, and Paco Najarro
Subjects: Physics, business.industry, Linear polarization, Bolometer, Detector, Polarimetry, FOS: Physical sciences, Polarimeter, Spica, Spectral bands, Polarization (waves), 7. Clean energy, law.invention, Optics, law, business, Astrophysics - Instrumentation and Methods for Astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM)
Abstract: We present the B-BOP instrument, a polarimetric camera on board the future ESA-JAXA SPICA far-infrared space observatory. B-BOP will allow the study of the magnetic field in various astrophysical environments thanks to its unprecedented ability to measure the linear polarization of the submillimeter light. The maps produced by B-BOP will contain not only information on total power, but also on the degree and the angle of polarization, simultaneously in three spectral bands (70, 200 and 350 microns). The B-BOP detectors are ultra-sensitive silicon bolometers that are intrinsically sensitive to polarization. Their NEP is close to 10E-18 W/sqrt(Hz). We will present the optical and thermal architectures of the instrument, we will detail the bolometer design and we will show the expected performances of the instrument based on preliminary lab work., 10 pages, 6 figures, SPIE proceeding: Astronomical Telescopes + Instrumentation 2020
Published: 2021

6. An optical test facility for the B-BOP bolometers of the SPICA mission

Author: Daniel Desforge, Camille Gennet, X.-F. Navick, J. Martignac, Albrecht Pöglitsh, V. Reveret, L. Rodriguez, and Didier Dubreuil
Subjects: Cryostat, Physics, Galactic astronomy, Optical testing, business.industry, Bolometer, Spica, law.invention, Telescope, Optics, Light source, law, Optical test, business
Abstract: The B-BOP instrument for the SPICA mission will use a brand new generation of submillimeter bolometers. An ultra-low background testbed for these bolometers has been developed for phase A of ESA. Inside the test cryostat lies a submillimeter light source designed to emit different flux, each of them with the same spectrum, at high temperature. To make sure the light arriving on the bolometers is faint, we use an inversed telescope to dilute the light. This allowed us to perform the first measurements on bolometer arrays produced by CEA-Leti.
Published: 2020

7. A regioselective C7 bromination and C7 palladium-catalyzed Suzuki-Miyaura cross-coupling arylation of 4-substituted NH-free indazoles

Author: Jérôme Graton, Saïd El Kazzouli, Jacques Lebreton, Monique Mathé-Allainmat, Didier Dubreuil, Sylvain Collet, Khalid Boujdi, Nabil El Brahmi, Mohamed Akssira, Modélisation Et Spectroscopie (ModES), Chimie Et Interdisciplinarité : Synthèse, Analyse, Modélisation (CEISAM), Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), and Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)
Subjects: Reaction conditions, 010405 organic chemistry, General Chemical Engineering, Halogenation, Regioselectivity, chemistry.chemical_element, bromination, General Chemistry, 010402 general chemistry, 01 natural sciences, Combinatorial chemistry, 0104 chemical sciences, Catalysis, Coupling (electronics), chemistry, regioselective, [CHIM]Chemical Sciences, Palladium
Abstract: International audience; A direct and efficient regioselective C7-bromination of 4-substituted 1H-indazole has been achieved. Subsequently, a successful palladium-mediated Suzuki–Miyaura reaction of C7-bromo-4-substituted-1H-indazoles with boronic acids has been performed under optimized reaction conditions. A series of new C7 arylated 4-substituted 1H-indazoles was obtained in moderate to good yields.
Published: 2020

8. Lipidic synthetic alkaloids as SK3 channel modulators. Synthesis and biological evaluation of 2-substituted tetrahydropyridine derivatives with potential anti-metastatic activity

Author: Sana Kouba, Monique Mathé-Allainmat, Paul-Alain Jaffrès, Christophe Vandier, Muriel Pipelier, Aurélie Chantôme, Jacques Lebreton, Didier Dubreuil, Xuexin Zhang, Marie Potier-Cartereau, Mohamed Trebak, Romain Félix, Julien Braire, Nutrition, croissance et cancer (U 1069) (N2C), Université de Tours (UT)-Institut National de la Santé et de la Recherche Médicale (INSERM), Chimie Et Interdisciplinarité : Synthèse, Analyse, Modélisation (CEISAM), Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Chimie, Electrochimie Moléculaires et Chimie Analytique (CEMCA), Université de Brest (UBO)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut Brestois Santé Agro Matière (IBSAM), Université de Brest (UBO), Department of Cellular and Molecular Physiology (DCMP), Pennylvania State University College of Medicine, This work has been developed with technical (ImPACcell platform, Rennes (F) R. Le Guével) and financial supports from the 'Réseau Canaux Ioniques' of the 'Cancéropôle Grand Ouest'. We are also deeply grateful to the 'Ligue Contre le Cancer' for financial supports (interregional grants: CSIRGO 2015). This work was supported by 'University of Tours', 'Région Centre Val de Loire', 'INSERM', and Sana Kouba held her fellowship from the 'Ministère de l'enseignement supérieur et de la recherche'., Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Tours, Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes-Centre National de la Recherche Scientifique (CNRS), Université de Nantes - Faculté des Sciences et des Techniques, Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université de Nantes (UN)-Université de Nantes (UN)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), MATHE-ALLAINMAT, Monique, and Université de Tours-Institut National de la Santé et de la Recherche Médicale (INSERM)
Subjects: Pyrrolidines, cell migration, Small-Conductance Calcium-Activated Potassium Channels, [SDV]Life Sciences [q-bio], [CHIM.THER]Chemical Sciences/Medicinal Chemistry, 01 natural sciences, Drug Discovery, Cells, Cultured, ComputingMilieux_MISCELLANEOUS, amphiphiles, 0303 health sciences, Molecular Structure, tetrahydropyridine derivatives, ORAI1, [CHIM.ORGA]Chemical Sciences/Organic chemistry, amphiphilic compounds, Cell migration, General Medicine, Lipids, 3. Good health, Gene isoform, [CHIM.THER] Chemical Sciences/Medicinal Chemistry, chemistry.chemical_element, Antineoplastic Agents, [SDV.CAN]Life Sciences [q-bio]/Cancer, Calcium, Structure-Activity Relationship, 03 medical and health sciences, Alkaloids, breast cancer, Breast cancer, SK3, Mediator, medicine, Humans, [CHIM]Chemical Sciences, Ca2+ -activated K + channels, Cell Proliferation, 030304 developmental biology, Pharmacology, Dose-Response Relationship, Drug, 010405 organic chemistry, Organic Chemistry, canaux ioniques, medicine.disease, 0104 chemical sciences, HEK293 Cells, chemistry, Cancer cell, Cancer research, Drug Screening Assays, Antitumor
Abstract: International audience; Small Conductance Calcium (Ca 2-)-activated potassium (K-) channels (SKCa) are now proved to be involved in many cancer cell behaviors such as proliferation or migration. The SIG channel isoform was particularly described in breast cancer where it can be associated with the Orai 1 Ca 2-channel to form a complex that regulates the ca 2-homeostasis during tumor development and acts as a potent mediator of bone metastases development in vivo. Until now, very few specific blockers of Orail and/or SIG have been developed as potential anti-metastatic compounds. ln this study, we illustrated the synthesis of new families of lipophilic pyridine and tetrahydropyridine derivatives designed as potential modulators of SK3 channel. The toxicity of the newly synthesized compounds and their migration effects were evaluated on the breast cancer cell line MDA-MB-435s. Two molecules (7a and toc) demonstrated a significant decrease in the SK3 channel-dependent migration as well as the SK3/Orai1-related Ca 2-entry. Current measurements showed that these compounds are more likely SK3-selective. Taken all together these results suggest that such molecules could be considered as promising anti-metastatic drugs in breast cancer.
Published: 2020

9. 73P αGalCer/antibody complex targeting EGFR-tumor-associated iNKT to restore the immune response

Author: A. Pattinec, Didier Dubreuil, J. Le Pendu, and J.-Y. Douillard
Subjects: Immune system, Oncology, biology, business.industry, Immunology, biology.protein, Medicine, Hematology, Antibody, business
Published: 2020

10. Rational modification, synthesis and biological evaluation of N-substituted phthalazinone derivatives designed to target interleukine-15 protein

Author: Monique Mathé-Allainmat, Jacques Lebreton, Jimmy Smadja, Laurence Arzel, Agnès Quéméner, Erwan Mortier, Benoit Sicard, Didier Dubreuil, Aurélien Leray, Mike Maillasson, Centre de Recherche en Cancérologie et Immunologie Nantes-Angers (CRCINA), Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Nantes - UFR de Médecine et des Techniques Médicales (UFR MEDECINE), Université de Nantes (UN)-Université de Nantes (UN)-Centre hospitalier universitaire de Nantes (CHU Nantes)-Centre National de la Recherche Scientifique (CNRS)-Université d'Angers (UA), Immunobiology of Human αβ and γδ T Cells and Immunotherapeutic Applications (CRCINA-ÉQUIPE 1), Université de Nantes (UN)-Université de Nantes (UN)-Centre hospitalier universitaire de Nantes (CHU Nantes)-Centre National de la Recherche Scientifique (CNRS)-Université d'Angers (UA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Nantes - UFR de Médecine et des Techniques Médicales (UFR MEDECINE), LabEx IGO 'Immunotherapy, Graft, Oncology' [Nantes], Chimie Et Interdisciplinarité : Synthèse, Analyse, Modélisation (CEISAM), Centre National de la Recherche Scientifique (CNRS)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN), Plateforme IMPACT Nantes (CRCINA-IMPACT), Centre de Recherche en Cancérologie Nantes-Angers (CRCNA), Centre Hospitalier Universitaire d'Angers (CHU Angers), PRES Université Nantes Angers Le Mans (UNAM)-PRES Université Nantes Angers Le Mans (UNAM)-Hôtel-Dieu de Nantes-Institut National de la Santé et de la Recherche Médicale (INSERM)-Hôpital Laennec-Centre National de la Recherche Scientifique (CNRS)-Faculté de Médecine d'Angers-Centre hospitalier universitaire de Nantes (CHU Nantes)-Centre Hospitalier Universitaire d'Angers (CHU Angers), PRES Université Nantes Angers Le Mans (UNAM)-PRES Université Nantes Angers Le Mans (UNAM)-Hôtel-Dieu de Nantes-Institut National de la Santé et de la Recherche Médicale (INSERM)-Hôpital Laennec-Centre National de la Recherche Scientifique (CNRS)-Faculté de Médecine d'Angers-Centre hospitalier universitaire de Nantes (CHU Nantes), Université d'Angers (UA)-Université de Nantes (UN)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre hospitalier universitaire de Nantes (CHU Nantes), Université d'Angers (UA)-Université de Nantes (UN)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre hospitalier universitaire de Nantes (CHU Nantes)-Université d'Angers (UA)-Université de Nantes (UN)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre hospitalier universitaire de Nantes (CHU Nantes), LabEX IGO Immunothérapie Grand Ouest, Nantes Université (Nantes Univ), Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Mortier, Erwan, and Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)
Subjects: [SDV.IMM] Life Sciences [q-bio]/Immunology, medicine.medical_treatment, T cell, Clinical Biochemistry, Pharmaceutical Science, autoimmune disease, 01 natural sciences, Biochemistry, Cell Line, Structure-Activity Relationship, Drug Discovery, medicine, Humans, Receptor, Molecular Biology, Interleukin-15, Virtual screening, 010405 organic chemistry, Chemistry, Spectrum Analysis, Organic Chemistry, Interleukin, Protein-protein interaction PPI, inflammatory disease, 0104 chemical sciences, 3. Good health, Cell biology, inhibitor, 010404 medicinal & biomolecular chemistry, Cytokine, medicine.anatomical_structure, Interleukin 15, Phthalazines, [SDV.IMM]Life Sciences [q-bio]/Immunology, Molecular Medicine, IL-15Rbeta, Pharmacophore, CD8
Abstract: International audience; Interleukin (IL)-15 is a pleiotropic cytokine structurally close to IL-2 and sharing with the IL-2Rβ and γc receptor (R) subunits. IL-15 plays important roles in innate and adaptative immunity, supporting the activation and proliferation of NK, NK-T, and CD8 + T cells. Over-expression of IL-15 has been shown to participate to the development of inflammatory and autoimmune diseases and diverse T cell malignancies. This study is in continuity of our previous work through which a family of small-molecule inhibitors impeding IL-15/IL-2Rβ interaction with sub-micromolar activity has been identified using pharmacophore-based virtual screening and hit optimization methods. With the aim to improve the efficacy and selectivity of our lead inhibitor, specific modifications have been introduced on the basis of optimized SAR and modelisation. The new series of compounds generated have been evaluated for their capacity to inhibit the proliferation as well as the downstream signaling of IL-15-dependent cells and to bind to IL-15.
Published: 2021

11. Discovery of a Small-Molecule Inhibitor of Interleukin 15: Pharmacophore-Based Virtual Screening and Hit Optimization

Author: Yannick Jacques, Monique Mathé-Allainmat, Laurence Arzel, Mike Maillasson, Erwan Mortier, Jacques Lebreton, Romy Vomiandry, Didier Dubreuil, Agnès Quéméner, Benoit Sicard, Centre de Recherche en Cancérologie et Immunologie Nantes-Angers (CRCINA), Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Nantes - UFR de Médecine et des Techniques Médicales (UFR MEDECINE), Université de Nantes (UN)-Université de Nantes (UN)-Centre hospitalier universitaire de Nantes (CHU Nantes)-Centre National de la Recherche Scientifique (CNRS)-Université d'Angers (UA), Chimie Et Interdisciplinarité : Synthèse, Analyse, Modélisation (CEISAM), Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), This work was funded by the programs CIMATH2 (Ciblage Moléculaire et Applications Thérapeutiques 2) and PIRAMID (Protein‐protein Interactions in Rational Approaches for Medicinal Innovative Drugs) supported by La Région Pays de la Loire. R.V. was supported by a fellowship from La Région Pays de la Loire. We thank CHEM)Symbiose and IMPACT facilities for technical assistance., Bernardo, Elizabeth, Université d'Angers (UA)-Université de Nantes (UN)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre hospitalier universitaire de Nantes (CHU Nantes), and Université de Nantes (UN)-Université de Nantes (UN)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: 0301 basic medicine, medicine.medical_treatment, [SDV.CAN]Life Sciences [q-bio]/Cancer, 01 natural sciences, Cell Line, Small Molecule Libraries, Mice, Structure-Activity Relationship, 03 medical and health sciences, [SDV.CAN] Life Sciences [q-bio]/Cancer, Drug Discovery, medicine, Animals, Humans, Receptor, Cell Proliferation, Interleukin-15, Virtual screening, 010405 organic chemistry, Chemistry, Interleukin, Stereoisomerism, Triazoles, Small molecule, 0104 chemical sciences, 3. Good health, Cell biology, Interleukin-2 Receptor beta Subunit, Molecular Docking Simulation, 030104 developmental biology, Cytokine, Interleukin 15, Immunology, Phthalazines, Molecular Medicine, Pharmacophore, Databases, Chemical, CD8
Abstract: International audience; Interleukin (IL)-15 is a pleiotropic cytokine, which is structurally close to IL-2 and shares with it the IL-2 β and γ receptor (R) subunits. By promoting the activation and proliferation of NK, NK-T and CD8+ T cells, IL-15 plays important roles in innate and adaptative immunity. Moreover, the association of high levels of IL-15 expression with inflammatory and autoimmune diseases has led to the development of various antagonistic approaches targeting IL- 15. This study is an original approach aimed at discovering small-molecule inhibitors impeding IL-15/IL-15R interaction. A pharmacophore and docking-based virtual screening of compound libraries led to the selection of 240 high-scoring compounds, 36 of which were found to bind IL-15, to inhibit the binding of IL-15 to the IL-2Rβ chain and/or the proliferation of IL-15-dependent cells. One of them was selected as a hit, optimized by a structure-activity relationship approach, leading to the first small-molecule IL-15 inhibitor with sub-micromolar activity.
Published: 2017

12. 3,4-Dideoxy-3,3,4,4-tetrafluoro- and 4-OH epimeric 3-deoxy-3,3-difluoro-α-GalCer analogues: Synthesis and biological evaluation on human iNKT cells stimulation

Author: Arnaud Tessier, Jézabel Rocher, Katy Akoumany, Allan Patinec, Virginie Blot, Didier Dubreuil, Jacques Le Pendu, Jean-Yves Le Questel, Bruno Linclau, Samuel Golten, Jérôme Graton, Muriel Pipelier, Denis Jacquemin, J.Y. Douillard, Jacques Lebreton, Chimie Et Interdisciplinarité : Synthèse, Analyse, Modélisation (CEISAM), Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Host-Pathogen Interactions in the Regulation of Immune Responses (CRCINA-ÉQUIPE 5), Centre de Recherche en Cancérologie et Immunologie Nantes-Angers (CRCINA), Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Nantes - UFR de Médecine et des Techniques Médicales (UFR MEDECINE), Université de Nantes (UN)-Université de Nantes (UN)-Centre hospitalier universitaire de Nantes (CHU Nantes)-Centre National de la Recherche Scientifique (CNRS)-Université d'Angers (UA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Nantes - UFR de Médecine et des Techniques Médicales (UFR MEDECINE), Université de Nantes (UN)-Université de Nantes (UN)-Centre hospitalier universitaire de Nantes (CHU Nantes)-Centre National de la Recherche Scientifique (CNRS)-Université d'Angers (UA), Laboratoire Ecosystèmes Microbiens et Molécules Marines pour les Biotechnologies [IFREMER, Nantes], and Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)
Subjects: Models, Molecular, Stereochemistry, [SDV]Life Sciences [q-bio], Molecular Conformation, Receptors, Antigen, T-Cell, Galactosylceramides, 01 natural sciences, Work related, 03 medical and health sciences, chemistry.chemical_compound, Interferon-gamma, Amide, Drug Discovery, Electronic effect, [CHIM]Chemical Sciences, Humans, Receptor, Deoxygenation, ComputingMilieux_MISCELLANEOUS, 030304 developmental biology, Pharmacology, 0303 health sciences, Interleukin-13, biology, 010405 organic chemistry, Hydrogen bond, Organic Chemistry, T-cell receptor, Hydrogen Bonding, Stereoisomerism, General Medicine, 0104 chemical sciences, chemistry, CD1D, biology.protein, Natural Killer T-Cells, Antigens, CD1d, HeLa Cells, Protein Binding
Abstract: 20 iNKT cells recognize CD1d/-galactosylceramide (-GalCer) complexes via their invariant 21 TCR receptor and stimulate the immune response. Many -GalCer analogues have been 22 investigated to interrogate this interaction. Following our previous work related to the 23 modification of the hydrogen bond network between -GalCer and CD1d, we have now 24 focused our attention on the synthesis of 3-deoxy-3,3-difluoro-and 3,4-dideoxy-3,3,4,4-25 tetrafluoro-α-GalCer analogues, and studied their ability to stimulate human iNKT cells. In 26 2 each case, deoxygenation at the indicated positions was accompanied by difluoro introduction 1 in order to evaluate the resulting electronic effect on the stability of the ternary 2 CD1d/Galcer/TCR complex which has been rationalized by modeling study. With deoxy-3 difluorination at the 3-position, the two epimeric 4-OH analogues were investigated to establish 4 their capacity to compensate for the lack of the hydrogen bond donating group at the 3-position. 5 The 3,4-dideoxytetrafluoro analogue was of interest to highlight the amide NH-bond hydrogen 6 bond properties. 7 8
Published: 2019

13. SEPAGE: a proton-ion-electron spectrometer for LMJ-PETAL

Author: Ange Lotode, Katarzyna Jakubowska, Xavier Leboeuf, N. Rabhi, Julien Fuchs, François Granet, Laurent Serani, Didier Raffestin, Didier Dubreuil, Isabelle Lantuejoul, Antoine Chancé, G. Boutoux, Bruno Marchet, A. Duval, B. Rosse, B. Vauzour, Jean-Christian Toussaint, Francis Harrault, Chon Pès, L. Lecherbourg, Christophe Rousseaux, Didier Leboeuf, Jean-Eric Ducret, Pierre Prunet, T. Caillaud, Jean-Christophe Guillard, Denis Loiseau, Bernard Gastineau, S. Hulin, T. Ceccotti, Dimitri Batani, and Charles Reverdin
Subjects: Physics, Range (particle radiation), Electron spectrometer, Proton, Spectrometer, 010308 nuclear & particles physics, business.industry, Electron, Laser, 01 natural sciences, Charged particle, 030218 nuclear medicine & medical imaging, law.invention, Ion, 03 medical and health sciences, 0302 clinical medicine, Optics, law, 0103 physical sciences, business
Abstract: The SEPAGE spectrometer (Spectrometre Electrons Protons A Grandes Energies) was realized within the PETAL+ project funded by the French ANR (French National Agency for Research). This plasma diagnostic, installed on the LMJ-PETAL laser facility, is dedicated to the measurement of charged particle energy spectra generated by experiments using PETAL (PETawatt Aquitaine Laser). SEPAGE is inserted inside the 10-meter diameter LMJ experimental chamber with a SID (Diagnostic Insertion System) in order to be close enough to the target. It is composed of two Thomson Parabola measuring ion spectra and more particularly proton spectra ranging from 0.1 to 20 MeV and from 8 to 200 MeV for the low and high energy channels respectively. The electron spectrum is also measured with an energy range between 0.1 and 150 MeV. The front part of the diagnostic carries a film stack that can be placed as close as 100 mm from the target center chamber. This stack allows a spatial and spectral characterization of the entire proton beam. It can also be used to realize proton radiographies.
Published: 2018

14. Primary and secondary mirror manufacturing for COLIBRI ground follow-up telescope of the SVOM mission

Author: Kjetil Dohlen, Didier Dubreuil, F. A. Uribe, S. Cuevas Cardona, C. Meessen, S. Basa, J. Boy, B. Cordier, D. Corre, Emmanuel Hugot, P. Gallais, F. Quirós, J. Platzer, Alan M. Watson, H. Valentin, Jorge Fuentes-Fernández, Liliana Figueroa, W. H. Lee, J-L. Atteia, A. Le Van Suu, Rosalía Langarica Lebre, P. E. Blanc, E. Jimenez-Bailon, O. Boulade, E. Cadena, J. Floriot, J. F. Le Borgne, A. F. Simon, F. Dolon, R. Mathon, Samuel Ronayette, Marc Ferrari, M. Ageron, E. Pallier, J. L. Ochoa, Damien Dornic, Michel Marcos, P. Ambert, and A. Klotz
Subjects: Telescope, Computer science, law, Primary (astronomy), Astrophysics::High Energy Astrophysical Phenomena, Celestial coordinate system, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy, Secondary mirror, law.invention
Abstract: COLIBRI is one of the two robotic ground follow-up telescopes for the SVOM (Space Variable Object Monitor) mission dedicated to the study of gamma-ray bursts, allowing determination of precise celestial coordinates of the detected bursts. COLIBRI telescope is a two-mirror Ritchey-Chretien telescope whose concave primary and convex secondary mirrors have diameters of 1325mm and 485mm respectively. The mirrors are currently manufactured at LAM (Laboratoire d’Astrophysique de Marseille). In this article, the advancement of the work is presented. We also give a global overview and status of the COLIBRI project.
Published: 2018

15. Structural design techniques applied in astronomical instruments

Author: D. Corre, Kjetil Dohlen, Salvador Cuevas, Samuel Ronayette, Didier Dubreuil, J. Boy, J. F. Le Borgne, F. Dolon, Marc Ferrari, Carlos Tejada, J. Floriot, Emmanuel Hugot, R. Mathon, P. Ambert, F. Quirós, M. Ageron, B. Cordier, P. E. Blanc, Jorge Fuentes-Fernández, Alejandro Farah, C. Meessen, A. Klotz, Silvio J. Tinoco, Alan M. Watson, Jaime Ruíz-Diáz-Soto, Damien Dornic, R. Langarica, Fernando Ángeles, J-L. Atteia, J. Platzer, O. Boulade, Michel Marcos, H. Valentin, P. Gallais, E. Pallier, S. Basa, and A. Le Van Suu
Subjects: Teamwork, Work (electrical), Computer science, media_common.quotation_subject, Key (cryptography), Position (finance), Instrumentation (computer programming), media_common, Reliability engineering
Abstract: We present in this article some of the techniques applied at the Instituto de Astronomia of the Universidad Nacional Autonoma de Mexico (IA-UNAM) to the mechanical structural design for astronomical instruments. With this purpose we use two recent projects developed by the Instrumentation Department. The goal of this work is to give guidelines about support structures design for achieving a faster and accurate astronomical instruments design. The main guidelines that lead all the design stages for instrument subsystems are the high-level requirements and the overall specifications. From these, each subsystem needs to get its own requirements, specifications, modes of operation, relative position, tip/tilt angles, and general tolerances. Normally these values are stated in the error budget of the instrument. Nevertheless, the error budget is dynamic, it is changing constantly. Depending on the manufacturing accuracy achieved, the error budget is again distributed. That is why having guidelines for structural design helps to know some of the limits of tolerances in manufacture and assembly. The error budget becomes then a quantified way for the interaction between groups; it is the key for teamwork.
Published: 2018

16. End-to-end simulations for COLIBRI, ground follow-up telescope for the SVOM mission

Author: Samuel Ronayette, E. Pallier, D. Turpin, E. Cadena, S. Basa, Jorge Fuentes-Fernández, Liliana Figueroa, D. Corre, Michel Marcos, J. Floriot, J. L. Ochoa, P. E. Blanc, J-L. Atteia, Alejandro Farah, F. Quirós, J. F. Le Borgne, R. Mathon, F. Dolon, A. Klotz, W. H. Lee, E. Jimenez-Bailon, O. Boulade, Fernando Ángeles, A. Le Van Suu, J. Platzer, B. Cordier, H. Valentin, S. D. Vergani, Alan M. Watson, Didier Dubreuil, S. Cuevas Cardona, Damien Dornic, P. Gallais, J. Boy, M. Ageron, P. Ambert, R. Langarica Lebre, C. Meessen, Laboratoire d'Astrophysique de Marseille (LAM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Centre de Physique des Particules de Marseille (CPPM), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Aix Marseille Université (AMU), Institut Pythéas (OSU PYTHEAS), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Centre National de la Recherche Scientifique (CNRS), Département d'Astrophysique (ex SAP) (DAP), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Galaxies, Etoiles, Physique, Instrumentation (GEPI), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Aix Marseille Université (AMU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut de Recherche pour le Développement (IRD), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)
Subjects: 010308 nuclear & particles physics, Computer science, Astrophysics::High Energy Astrophysical Phenomena, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy, Astrophysics::Cosmology and Extragalactic Astrophysics, Python (programming language), 01 natural sciences, Redshift, law.invention, Telescope, Open source, End-to-end principle, law, 0103 physical sciences, Astrophysics::Earth and Planetary Astrophysics, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], Gamma-ray burst, 010303 astronomy & astrophysics, computer, Astrophysics::Galaxy Astrophysics, computer.programming_language, Photometric redshift
Abstract: International audience; We present an overview of the development of the end-to-end simulations programs developed for COLIBRI (Catching OpticaL and Infrared BRIght), a 1.3m robotic follow-up telescope of the forthcoming SVOM (Space Variable Object Monitor) mission dedicated to the detection and study of gamma-ray bursts (GRBs). The overview contains a description of the Exposure Time Calculator, Image Simulator and photometric redshift code developed in order to assess the performance of COLIBRI. They are open source Python packages and were developed to be easily adaptable to any optical/ Near-Infrared imaging telescopes. We present the scientific performances of COLIBRI, which allows detecting about 95% of the current GRB dataset. Based on a sample of 500 simulated GRBs, a new Bayesian photometric redshift code predicts a relative photometric redshift accuracy of about 5% from redshift 3 to 7.
Published: 2018

17. The selectivity of Marinopyrrole A to induce apoptosis in MCL1 high BCL2 low expressing myeloma cells is related to its ability to impair protein translation

Author: Christelle Dousset, Géraldine Descamps, Logan Audiger, Jacques Lebreton, Patricia Gomez-Bougie, Anne Schnitzler, Arnaud Tessier, Martine Amiot, Didier Dubreuil, Catherine Pellat-Deceunynck, Bernardo, Elizabeth, Centre de Recherche en Cancérologie Nantes-Angers (CRCNA), Centre Hospitalier Universitaire d'Angers (CHU Angers), PRES Université Nantes Angers Le Mans (UNAM)-PRES Université Nantes Angers Le Mans (UNAM)-Hôtel-Dieu de Nantes-Institut National de la Santé et de la Recherche Médicale (INSERM)-Hôpital Laennec-Centre National de la Recherche Scientifique (CNRS)-Faculté de Médecine d'Angers-Centre hospitalier universitaire de Nantes (CHU Nantes), Chimie Et Interdisciplinarité : Synthèse, Analyse, Modélisation (CEISAM), Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)
Subjects: 0301 basic medicine, BCL2, Translation, Translation (biology), Myeloma, Apoptosis, [SDV.CAN]Life Sciences [q-bio]/Cancer, Hematology, Biology, medicine.disease, Cell biology, Myeloid Cell Leukemia Sequence 1 Protein, 03 medical and health sciences, 030104 developmental biology, MCL1, Family members, [SDV.CAN] Life Sciences [q-bio]/Cancer, Gene expression, medicine, Protein biosynthesis, Selectivity, Multiple myeloma, ComputingMilieux_MISCELLANEOUS
Abstract: International audience; ..
Published: 2018

18. The Role of Seven-Coordination in Ru-Catalyzed Water Oxidation

Author: Arnaud Tessier, Antoni Llobet, Jordi Benet-Buchholz, Mehmed Z. Ertem, Jacques Lebreton, Muriel Pipelier, Roc Matheu, Xavier Sala, Didier Dubreuil, Chimie Et Interdisciplinarité : Synthèse, Analyse, Modélisation (CEISAM), Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Département d'Astrophysique (ex SAP) (DAP), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Institute of Chemical Research of Catalonia (ICIQ), Departament de Química [Barcelona] (UAB), Universitat Autònoma de Barcelona (UAB), Université Paris 1 Panthéon-Sorbonne - UFR Histoire (UP1 UFR09), Université Paris 1 Panthéon-Sorbonne (UP1), Université de Nantes (UN)-Université de Nantes (UN)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Université Paris 1 Panthéon-Sorbonne - École d'Histoire (UP1 UFR09)
Subjects: 010405 organic chemistry, Chemistry, Ligand, Aquation, General Chemistry, 010402 general chemistry, Electrochemistry, Electrocatalyst, 01 natural sciences, Redox, Catalysis, 0104 chemical sciences, chemistry.chemical_compound, Crystallography, Pyridine, [CHIM]Chemical Sciences, Density functional theory
Abstract: A family of Ru complexes based on the pentadentate ligand t5a(3-) ((2,5-bis(6-carboxylatopyridin-2-yl)pyrrol-1-ide) and pyridine (py) that includes \Ru-II(Ht5a-kappa-(NO)-O-2)(py)(3)\ (1H(II)(kappa-(NO)-O-2)), \Ru-III(t5a-kappa-(NO1.5)-O-3)(py)(2)\ (2(III)(kappa-(NO1.5)-O-3)), and \Ru-IV(t5a-kappa-(NO2)-O-3)(py)(2)\(+) (\2(IV)(kappa-(NO2)-O-3)\(+)) has been prepared and thoroughly characterized. Complexes 1H(II)(kappa-(NO)-O-2), 2(III)(kappa-(NO1.5)-O-3), and \2(IV)(kappa-(NO2)-O-3)\(+) have been investigated in solution by spectroscopic methods (NMR, UV-vis) and in the solid state by single-crystal X-ray diffraction analysis and complemented by density functional theory (DFT) calculations. The redox properties of complex 2(III)(kappa-(NO1.5)-O-3) have been studied by electrochemical methods (CV and DPV), showing its easy access to high oxidation states, thanks to the trianionic nature of the t5a(3-) ligand. Under neutral to basic conditions complex \2(IV)(kappa-(NO2)-O-3)\(+) undergoes aquation, generating \Ru-IV(OH)(t5a-kappa-(NO)-O-2)(py)(2)\ (2(IV)(OH)(kappa-(NO)-O-2)). Further oxidation of the complex forms \Ru-V(O)(t5a-kappa-(NO)-O-2)(py)(2)\ (2(V)(O)(kappa-(NO)-O-2)), which is a very efficient water oxidation catalyst, reaching a TOFMAX value of 9400 s(-1) at pH 7.0, as measured via foot of the wave analysis. The key to fast kinetics for the catalytic oxidation of water to dioxygen by 2(V)(O)(kappa-(NO)-O-2) is due not only to the easy access to high oxidation states but also to the intramolecular hydrogen bonding provided by the noncoordinated dangling carboxylate at the transition state, as corroborated by DFT calculations.
Published: 2018

19. Metal-Coordination-Assisted Folding and Guest Binding in Helical Aromatic Oligoamide Molecular Capsules

Author: Barbara Wicher, Guillaume Lautrette, Virginie Blot, Jacques Lebreton, Muriel Pipelier, Ivan Huc, Didier Dubreuil, Maxime Horeau, Yann Ferrand, Chimie Et Interdisciplinarité : Synthèse, Analyse, Modélisation (CEISAM), Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Chimie et Biologie des Membranes et des Nanoobjets (CBMN), École Nationale d'Ingénieurs des Travaux Agricoles - Bordeaux (ENITAB)-Institut de Chimie du CNRS (INC)-Université de Bordeaux (UB)-Centre National de la Recherche Scientifique (CNRS), and Université de Bordeaux (UB)-École Nationale d'Ingénieurs des Travaux Agricoles - Bordeaux (ENITAB)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Coordination sphere, Metal ions in aqueous solution, Sequence (biology), 010402 general chemistry, 01 natural sciences, Catalysis, Metal, chemistry.chemical_compound, Metallkoordination, Polymer chemistry, [CHIM]Chemical Sciences, Foldamere, Molekulare Erkennung, Helikale Konformationen, 010405 organic chemistry, Foldamer, General Medicine, General Chemistry, Wirt-Gast-Chemie, 0104 chemical sciences, Folding (chemistry), Monomer, chemistry, visual_art, Helix, visual_art.visual_art_medium
Abstract: International audience; The development of foldamer-based receptors is driven by the design of monomers with specific properties. Herein, we introduce a pyridazine-pyridine-pyridazine diacid monomer and its incorporation into helical aromatic oligoamide foldamer containers. This monomer codes for a wide helix diameter and can sequester metal ions on the inner wall of the helix cavity. Crystallographic studies and NMR titrations show that part of the metal coordination sphere remains available and may then promote the binding of a guest within the cavity. In addition to metal coordination, binding of the guest is assisted by cooperative interactions with the helix host, thereby resulting in significant enhancements depending on the foldamer sequence, and in slow guest capture and release on the NMR time scale. In the absence of metal ions, the pyridazine-pyridine-pyridazine monomer promotes an extended conformation of the foldamer that results in aggregation, including the formation of an intertwined duplex
Published: 2017

20. Intrapixel measurement techniques on large focal plane arrays for astronomical applications : a comparative study

Author: C. Ketchazo, P. Mulet, N. Guérineau, Olivier Boulade, Laurent M. Mugnier, T. Viale, Cyrille Delisle, F. de la Barrière, V. Moreau, G. Druart, Didier Dubreuil, Service d'Astrophysique, Commissariat à l'énergie atomique et aux énergies alternatives (CEA), ONERA - The French Aerospace Lab [Palaiseau], ONERA-Université Paris Saclay (COmUE), and André, Cécile
Subjects: [SPI.OPTI] Engineering Sciences [physics]/Optics / Photonic, Physics::Instrumentation and Detectors, Image quality, DETECTEUR OPTIQUE, OPTICAL SENSOR, 02 engineering and technology, 01 natural sciences, 010309 optics, 020210 optoelectronics & photonics, Optics, [SDU.ASTR.IM] Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], Computer Science::Multimedia, 0103 physical sciences, 0202 electrical engineering, electronic engineering, information engineering, Sensitivity (control systems), Projection (set theory), Physics, Pixel, Spatial filter, business.industry, Detector, Subpixel rendering, [SDU.ASTR.IM]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], MTF, FTM, Signal-to-noise ratio (imaging), Computer Science::Computer Vision and Pattern Recognition, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, business
Abstract: International audience; The intrapixel response is the signal detected by a single pixel illuminated by a Dirac distribution as a function of the position of this Dirac inside this pixel. It is also known as the pixel response function (PRF). This function measures the sensitivity variation at the subpixel scale and gives a spatial map of the sensitivity across a pixel. The variation of the pixel sensitivity finds its origin in the physical properties of the pixel. The measurement of this function gives information on effects which occur after the absorption of the incoming photons by the material. Therefore the knowledge of this function is of great interest, on the one hand for the technologist, who could check the quality of the pixels and study the phenomena related to the detection; and on the other hand, for the instrument scientist, who could evaluate the impact of the spatial filtering of the pixel on image quality.The knowledge of the intra-pixel sensitivity is also important to control and reduce the systematic errors in under-sampled instruments. Indeed, in these instruments, the variation of pixel sensitivity limits the performances of the system and contributes to the instrument error budget [1,2]. All these reasons brings ESA to require the measurement of the intra-pixel sensitivity with a resolution close to the tenth of the pixel in detector technology development activities.The techniques used to measure the intra-pixel response are based on the projection of optical probes on the detector. These techniques can be divided in two main approaches: the direct approach and the indirect approach.
Published: 2016

21. Stereoselective Synthesis of a Bicyclic Norsesquiterpene Backbone - A Possible Route to Nardosinane Derivatives

Author: Virginie Blot, Muriel Pipelier, Denis Jacquemin, Guillaume Viault, Didier Dubreuil, Anirban Kar, Ouassila Selaïmia-Ferdjani, Maxime Horeau, Xavier Guillory, Arnaud Tessier, Sambhaji P. Chavan, Jacky Pouessel, and Aurélien Planchat
Subjects: Bicyclic molecule, Diene, 010405 organic chemistry, Stereochemistry, Organic Chemistry, 010402 general chemistry, Sesquiterpene, 01 natural sciences, 0104 chemical sciences, chemistry.chemical_compound, Aldol reaction, chemistry, Organic chemistry, Stereoselectivity, Physical and Theoretical Chemistry
Abstract: We have developed an efficient diastereoselective synthetic route towards a nardosinane sesquiterpene scaffold. The strategy used a key bicyclic diene intermediate 11a, and allowed access to valuable polyoxygenated sesquiterpenes 21 and 22, which may be regarded as analogues of the natural sesquiterpenes laevinol B and fulvol acetate, respectively.
Published: 2013

22. Pd-Catalyzed Chemoselective Cross-Coupling Reaction of Triaryl- or Triheteroarylbismuth Compounds with 3,6-Dihalopyridazines

Author: Karène Urgin, Sylvie Condon, Muriel Pipelier, Christine Thobie-Gautier, Christophe Aube, Virginie Blot, Stéphane Sengmany, Eric Léonel, Jacques Lebreton, and Didier Dubreuil
Subjects: 010405 organic chemistry, Aryl, Organic Chemistry, chemistry.chemical_element, 010402 general chemistry, 01 natural sciences, Coupling reaction, 0104 chemical sciences, Catalysis, Bismuth, chemistry.chemical_compound, chemistry, Organic chemistry, Physical and Theoretical Chemistry, Chemoselectivity, Palladium
Abstract: The cross-coupling reactions of 3,6-dihalopyridazines with triaryl- or triheteroarylbismuth compounds were performed under palladium catalysis. The reaction was highly chemoselective, affording functionalized aryl- or heteroarylpyridazinyl chlorides in moderate to good yields.
Published: 2012

23. The selectivity of Marinopyrrole A to induce apoptosis in MCL1

Author: Patricia, Gomez-Bougie, Christelle, Dousset, Geraldine, Descamps, Anne, Schnitzler, Logan, Audiger, Arnaud, Tessier, Didier, Dubreuil, Jacques, Lebreton, Catherine, Pellat-Deceunynck, and Martine, Amiot
Subjects: Proto-Oncogene Proteins c-bcl-2, Cell Survival, Cell Line, Tumor, Protein Biosynthesis, Gene Expression, Humans, Myeloid Cell Leukemia Sequence 1 Protein, Apoptosis, Pyrroles, Multiple Myeloma
Published: 2016

24. The mid-infrared instrument for the James Webb Space Telescope: performance and operation of the Low-Resolution Spectrometer

Author: Karl D. Gordon, Alistair Glasse, Sebastian Fischer, J. Bouwman, Christine Chen, Samuel Ronayette, Gillian S. Wright, Thomas P. Greene, Didier Dubreuil, Dean C. Hines, O. D. Fox, David W. Wright, Fred Lahuis, Pierre-Olivier Lagage, Jérôme Amiaux, Patrice Bouchet, Sarah Kendrew, Silvia Scheithauer, and Ruyman Azzollini
Subjects: Physics, 010504 meteorology & atmospheric sciences, Spectrometer, business.industry, Low resolution, James Webb Space Telescope, Mid infrared, 01 natural sciences, Exoplanet, Stars, Optics, 0103 physical sciences, Spectroscopy, business, 010303 astronomy & astrophysics, Transit (satellite), 0105 earth and related environmental sciences
Abstract: We describe here the performance and operational concept for the Low Resolution Spectrometer (LRS) of the mid-infrared instrument (MIRI) for the James Webb Space Telescope. The LRS will provide R∼100 slit and slitless spectroscopy from 5 to 12 micron, and its design is optimised for observations of compact sources, such as exoplanet host stars. We provide here an overview of the design of the LRS, and its performance as measured during extensive test campaigns, examining in particular the delivered image quality, dispersion, and resolving power, as well as spectrophotometric performance. The instrument also includes a slitless spectroscopy mode, which is optimally suited for transit spectroscopy of exoplanet atmospheres. We provide an overview of the operational procedures and the differences ahead of the JWST launch in 2018.
Published: 2016

25. ChemInform Abstract: Reaction of Glyconitriles with Organometallic Reagents: Access to Acyl β-C-Glycosides

Author: Muriel Pipelier, Idriss Ella Obame, Prathap Ireddy, Stéphane Guillarme, Gilles Dujardin, Arnaud Nourry, Didier Dubreuil, Christine Saluzzo, and Nicolas E. S. Guisot
Subjects: chemistry.chemical_classification, C glycosides, Glycal, chemistry, Reagent, Reactivity (chemistry), General Medicine, Combinatorial chemistry
Abstract: A new strategy for the synthesis of acyl β-C-glycosides is described. The reactivity of glyconitriles toward organometallic reagents such as organomagnesium or organolithium derivatives was studied, affording acyl β-C-glycosides in moderate to good yields. In this study, glycal formation was efficiently prevented by deprotonating the hydroxyl group in position 2 of the glyconitriles during the process.
Published: 2016

26. High accuracy measurements of the intrapixel sensitivity of VIS to LWIR astronomical detectors : experimental demonstration

Author: G. Druart, C. Ketchazo, V. Moreau, Aurélie Bonnefois, N. Guérineau, Laurent M. Mugnier, Didier Dubreuil, T. Viale, F. de la Barrière, P. Mulet, Olivier Boulade, Cyrille Delisle, ONERA - The French Aerospace Lab [Palaiseau], ONERA-Université Paris Saclay (COmUE), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)
Subjects: Point spread function, Physics, Test bench, business.industry, DETECTEUR, Detector, Astrometry, 01 natural sciences, 010309 optics, Optics, FTM, 0103 physical sciences, Dark energy, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, Sensitivity (control systems), Projection (set theory), business, 010303 astronomy & astrophysics, Image resolution, PSF, Remote sensing
Abstract: International audience; The reduction of systematic effects is necessary to improve the accuracy in imaging and astrometry. For example, in Euclid Mission which aims at carrying out accurate measurements of dark energy and quantifying precisely its role in the evolution of the Universe, systematic effects need at be controlled to a level better than 10^-7 (Euclid, Science Book). To achieve this goal, a high-level of knowledge of the system point spread function (PSF) is required. This paper follows the concept- paper presented at the last SPIE conference and gives the recent developments achieved in the design of the test bench for the intrapixel sensitivity measurements. The measurement technique we use is based on the projection of a high spatial resolution periodic pattern on the detector using the self-imaging property of a new class of diffractive objects named continuously self-imaging gratings (CSIG) and developed at ONERA. The principle combines the potential of global techniques, which make measurements at once on the whole FPA, and the accuracy of spot-scan- based techniques, which provide high local precision.; La réduction des effets de détérioration de l'image est nécessaire pour améliorer la précision des données en imagerie et astrométrie. Par exemple, pour la mission EUCLID dont le but est la mesure fine de l'énergie noire et la quantification précise de son rôle dans l'évolution de l'univers, ces effets doivent être contrôlés à un niveau inférieur à 10^-7 (Euclid, Science book). Afin d'atteindre cet objectif, une très bonne connaissance de la fonction d'étalement du point (FEP) du système est requise. Ce papier fait suite au précédent proceeding présenté au dernier SPIE et présente les récents développements effectués dans le design du banc de test pour la mesure de la réponse intra-pixel. La technique de mesure utilisée est basée sur la projection du profil périodique à haute résolution spatiale sur le détecteur en utilisant les propriétés d'auto-imagerie d'une nouvelle classe d'objets diffractants appelés réseaux continument auto-imageants développés à l'ONERA. le principe combine le potentiel des techniques globales, qui permettent une mesure en une fois pour l'ensemble du plan focal, et la précision des techniques basées sur le spot-scan, qui fournissent de hautes précisions à l'échelle locale.
Published: 2016

27. Characterizing filaments in regions of high-mass star formation: High-resolution submilimeter imaging of the massive star-forming complex NGC 6334 with ArT\'eMiS

Author: V. Revéret, L. Rodriguez, J. Martignac, Michel Lortholary, Cyrille Delisle, Frédérique Motte, Didier Dubreuil, Doris Arzoumanian, P. Palmeirim, Eric Doumayrou, J. Le Pennec, François Visticot, H. Roussel, Tracey Hill, D. Russeil, Annie Zavagno, C. De Breuck, Nicola Schneider, A. Roy, Nicolas Peretto, Y. Shimajiri, Sylvain Bontemps, J. Tigé, Pascal Gallais, M. Hennemann, Vincent Minier, M. Talvard, Vera Konyves, Ph. André, Luc Dumaye, K. L. J. Rygl, Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut d'Astrophysique de Paris (IAP), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Laboratoire Magmas et Volcans (LMV), Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet [Saint-Étienne] (UJM)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire de Synthèse Organique (Hétérochimie organique, organoéléments et matériaux) (LSOHOOM), Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS), Département d'Astrophysique, de physique des Particules, de physique Nucléaire et de l'Instrumentation Associée (DAPNIA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Procédés, Matériaux et Energie Solaire (PROMES), Université de Perpignan Via Domitia (UPVD)-Centre National de la Recherche Scientifique (CNRS), FORMATION STELLAIRE 2016, Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de Marseille (LAM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), DAM Île-de-France (DAM/DIF), Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Département d'Astrophysique (ex SAP) (DAP), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Department of Mechanical Engineering, University of Bristol [Bristol], Toyota Technological Institute at Chicago [Chicago] (TTIC), Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Paris (ENS-PSL), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Paris (ENS Paris)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, and PSL Research University (PSL)-PSL Research University (PSL)-Université de Cergy Pontoise (UCP)
Subjects: 010504 meteorology & atmospheric sciences, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, law.invention, Telescope, Gravitation, Protein filament, law, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, QB, Physics, Star formation, Molecular cloud, Bolometer, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, Interstellar medium, Stars, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Astrophysics::Earth and Planetary Astrophysics, [SDU.ASTR.GA]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Galactic Astrophysics [astro-ph.GA]
Abstract: Herschel observations of nearby molecular clouds suggest that interstellar filaments and prestellar cores represent two fundamental steps in the star formation process. The observations support a picture of low-mass star formation according to which ~ 0.1 pc-wide filaments form first in the cold interstellar medium, probably as a result of large-scale compression of interstellar matter by supersonic turbulent flows, and then prestellar cores arise from gravitational fragmentation of the densest filaments. Whether this scenario also applies to regions of high-mass star formation is an open question, in part because Herschel data cannot resolve the inner width of filaments in the nearest regions of massive star formation. We used the bolometer camera ArTeMiS on the APEX telescope to map the central part of the NGC6334 complex at a factor of > 3 higher resolution than Herschel at 350 microns. Combining ArTeMiS data with Herschel data allowed us to study the structure of the main filament of the complex with a resolution of 8" or < 0.07 pc at d ~ 1.7 kpc. Our study confirms that this filament is a very dense, massive linear structure with a line mass ranging from ~ 500 Msun/pc to ~ 2000 Msun/pc over nearly 10 pc. It also demonstrates that its inner width remains as narrow as W ~ 0.15 +- 0.05 pc all along the filament length, within a factor of < 2 of the characteristic 0.1 pc value found with Herschel for lower-mass filaments in the Gould Belt. While it is not completely clear whether the NGC 6334 filament will form massive stars or not in the future, it is two to three orders of magnitude denser than the majority of filaments observed in Gould Belt clouds, and yet has a very similar inner width. This points to a common physical mechanism for setting the filament width and suggests that some important structural properties of nearby clouds also hold in high-mass star forming regions., 10 pages, 6 figures. A&A, in press
Published: 2016

28. Reaction of Glyconitriles with Organometallic Reagents: Access to Acyl β- C -Glycosides

Author: Stéphane Guillarme, Prathap Ireddy, Gilles Dujardin, Didier Dubreuil, Christine Saluzzo, Idriss Ella Obame, Arnaud Nourry, Muriel Pipelier, Nicolas E. S. Guisot, Institut des Molécules et Matériaux du Mans (IMMM), Le Mans Université (UM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Chimie Et Interdisciplinarité : Synthèse, Analyse, Modélisation (CEISAM), Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), and Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)
Subjects: chemistry.chemical_classification, C glycosides, Glycal, 010405 organic chemistry, [CHIM.ORGA]Chemical Sciences/Organic chemistry, Organic Chemistry, Nucleophilic acyl substitution, 010402 general chemistry, 01 natural sciences, 0104 chemical sciences, Acylation, chemistry, Reagent, Organic chemistry, Reactivity (chemistry), ComputingMilieux_MISCELLANEOUS
Abstract: A new strategy for the synthesis of acyl β-C-glycosides is described. The reactivity of glyconitriles toward organometallic reagents such as organomagnesium or organolithium derivatives was studied, affording acyl β-C-glycosides in moderate to good yields. In this study, glycal formation was efficiently prevented by deprotonating the hydroxyl group in position 2 of the glyconitriles during the process.
Published: 2016

29. Synthesis of Ribonucleosidic Dimers with an Amide Linkage from D-Xylose

Author: Fabrice Dénès, Didier Dubreuil, Jacques Lebreton, Virginie Silvestre, Monique Mathé-Allainmat, Laurence Arzel, Chimie Et Interdisciplinarité : Synthèse, Analyse, Modélisation (CEISAM), Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), and Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)
Subjects: 010405 organic chemistry, Stereochemistry, Organic Chemistry, Linkage (mechanical), Xylose, 010402 general chemistry, 01 natural sciences, 0104 chemical sciences, law.invention, Nucleobase, chemistry.chemical_compound, chemistry, law, Yield (chemistry), Amide, [CHIM]Chemical Sciences, Base sequence
Abstract: An original and efficient stereocontrolled synthesis of ribonucleosidic homo- and heterodimers has been achieved from inexpensive d-xylose. This successful strategy involved the sequential introduction of nucleobases, using two stereocontrolled N-glycosidation reactions, from a common two-furanoside amide-linked scaffold offering the possibility of obtaining any given base sequence. The pertinence of this approach is illustrated through the preparation of the homodimers UU-34 and TT-35 in 18 steps with an excellent overall yield of more than 10% from d-xylose, while the heterodimer route led to UT-39 in 19 steps with around 10% overall yield.
Published: 2016

30. Glycidyl alkoxysilane reactivities towards simple nucleophiles in organic media for improved molecular structure definition in hybrid materials

Author: Pierre Weiss, G.-O. Gratien, Xavier Guillory, Sylvia Colliec-Jouault, J. Le Bideau, Didier Dubreuil, Arnaud Tessier, Jacques Lebreton, Infection, Anti-microbiens, Modélisation, Evolution (IAME (UMR_S_1137 / U1137)), Université Paris 13 (UP13)-Université Paris Diderot - Paris 7 (UPD7)-Université Sorbonne Paris Cité (USPC)-Institut National de la Santé et de la Recherche Médicale (INSERM), Regenerative Medicine and Skeleton research lab (RMeS), Ecole Nationale Vétérinaire, Agroalimentaire et de l'alimentation Nantes-Atlantique (ONIRIS)-Centre hospitalier universitaire de Nantes (CHU Nantes)-Université de Nantes - UFR de Médecine et des Techniques Médicales (UFR MEDECINE), Université de Nantes (UN)-Université de Nantes (UN)-Institut National de la Santé et de la Recherche Médicale (INSERM), Laboratoire de Biotechnologies et Molecules Marines (LBMM), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Chimie Et Interdisciplinarité : Synthèse, Analyse, Modélisation (CEISAM), Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Institut des Matériaux Jean Rouxel (IMN), Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Ecole Polytechnique de l'Université de Nantes (EPUN), and Université de Nantes (UN)-Université de Nantes (UN)
Subjects: General Chemical Engineering, Epoxide, 02 engineering and technology, General Chemistry, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, Silane, 0104 chemical sciences, Characterization (materials science), chemistry.chemical_compound, chemistry, Nucleophile, Alkoxy group, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Molecule, Organic chemistry, Reactivity (chemistry), 0210 nano-technology, Hybrid material, ComputingMilieux_MISCELLANEOUS
Abstract: For hybrid materials, the relationship between the macroscopic properties and the molecular structures and dynamics at the microscopic between the organic and inorganic components level is crucial. The characterization of these components as well as their reactivity have to be emphasized in order to design and synthesize improved hybrids. We report herein the first comprehensive study of the reactivity in organic media of (3-glycidyloxypropyl)trialkoxysilanes, widely used as precursors in sol–gel hybrid synthesis, towards common nucleophiles. Thorough investigations of the reactions allowed us to draw clear conclusions about the reactivities of both epoxide and alkoxysilane functions. Furthermore, the nucleophile properties and the method of activations have a great influence on the reaction outcomes, and unexpected results were found in some cases. The importance of the nature of the alkoxy residues (methoxy, ethoxy…) was also investigated highlighting chemoselective reactions on glycidyl silane derivatives (GPTMS, GPTES and PECS) and opening a new library of original sol–gel precursors.
Published: 2016

31. Identification of a Foldaxane Kinetic Byproduct during Guest-Induced Single to Double Helix Conversion

Author: Quan Gan, Yann Ferrand, Nagula Chandramouli, Brice Kauffmann, Didier Dubreuil, Ivan Huc, and Christophe Aube
Subjects: Circular dichroism, Molecular model, Stereochemistry, Circular Dichroism, Molecular Conformation, Supramolecular chemistry, macromolecular substances, General Chemistry, Kinetic energy, Biochemistry, Catalysis, Kinetics, chemistry.chemical_compound, Crystallography, Colloid and Surface Chemistry, chemistry, Tartaric acid, Molecule, Nuclear Magnetic Resonance, Biomolecular
Abstract: An aromatic oligoamide sequence was designed and synthesized to fold in a single helix having a large cavity and to behave as a host for a dumbbell-shaped guest derived from tartaric acid. NMR, molecular modeling, and circular dichroism (CD) evidence demonstrated the rapid formation of this 1:1 host-guest complex and induction of the helix handedness of the host by the guest. This complex was found to be a long-lived kinetic supramolecular byproduct, as it slowly transformed into a 2:2 host-guest complex with two guest molecules bound at the extremities of a double helix formed by the host, as shown by NMR and CD spectroscopy and a solid-state structure. The guest also induced the handedness of the double helical host, but with an opposite bias. The chiroptical properties of the system were thus found to revert with time as the 1:1 complex formed first, followed by the 2:2 complex.
Published: 2012

32. SPICES: spectro-polarimetric imaging and characterization of exoplanetary systems

Author: John T. Trauger, Jean-Charles Augereau, Naoshi Murakami, Pierre Baudoz, Raphael Galicher, Mark C. Wyatt, Pierre-Olivier Lagage, Olivier Guyon, Anne-Lise Maire, Raffaele Gratton, Daphne Stam, Anthony Boccaletti, Dimitri Mawet, Spices team, Motohide Tamura, Samuel Ronayette, Christophe Verinaud, Michiel Min, Kerri Cahoy, Didier Dubreuil, Frans Snik, Jennifer Patience, W. A. Traub, Eric Pantin, Michiel Rodenhuis, Dino Mesa, Marc J. Kuchner, Jean-Michel Reess, Ruslan Belikov, Ingrid Mary Beerer, and Jean Schneider
Subjects: Physics, Solar System, Zodiacal light, 010504 meteorology & atmospheric sciences, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy, Astronomy and Astrophysics, 7. Clean energy, 01 natural sciences, Exoplanet, law.invention, Jupiter, Telescope, Stars, 13. Climate action, Space and Planetary Science, Planet, law, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Spectral resolution, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences
Abstract: SPICES (Spectro-Polarimetric Imaging and Characterization of Exoplanetary Systems) is a five-year M-class mission proposed to ESA Cosmic Vision. Its purpose is to image and characterize long-period extrasolar planets and circumstellar disks in the visible (450 - 900 nm) at a spectral resolution of about 40 using both spectroscopy and polarimetry. By 2020/22, present and near-term instruments will have found several tens of planets that SPICES will be able to observe and study in detail. Equipped with a 1.5 m telescope, SPICES can preferentially access exoplanets located at several AUs (0.5-10 AU) from nearby stars ($
Published: 2012

33. 3-Fluoro- and 3,3-Difluoro-3,4-dideoxy-KRN7000 Analogues as New Potent Immunostimulator Agents: Total Synthesis and Biological Evaluation in Human Invariant Natural Killer T Cells and Mice

Author: J.Y. Douillard, Christine Saluzzo, Stéphane Guillarme, Gilles Dujardin, Séverine Marionneau-Lambot, Jézabel Rocher, Jacques Le Pendu, Jean-Yves Le Questel, Michel Evain, Jacques Lebreton, Jean-Cédric Frison, Didier Dubreuil, Mette Diswall, Muriel Pipelier, Thibauld Oullier, Denis Jacquemin, Jérôme Graton, Julie Hunault, Virginie Blot, Chimie Et Interdisciplinarité : Synthèse, Analyse, Modélisation (CEISAM), Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Centre de Recherche en Cancérologie Nantes-Angers (CRCNA), Centre Hospitalier Universitaire d'Angers (CHU Angers), PRES Université Nantes Angers Le Mans (UNAM)-PRES Université Nantes Angers Le Mans (UNAM)-Hôtel-Dieu de Nantes-Institut National de la Santé et de la Recherche Médicale (INSERM)-Hôpital Laennec-Centre National de la Recherche Scientifique (CNRS)-Faculté de Médecine d'Angers-Centre hospitalier universitaire de Nantes (CHU Nantes), Cancéropôle du Grand Ouest, Université de Nantes (UN), Institut de Cancérologie de l'Ouest [Angers/Nantes] (UNICANCER/ICO), UNICANCER, Unité de chimie organique moléculaire et macromoléculaire (UCO2M), Le Mans Université (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Institut des Matériaux Jean Rouxel (IMN), Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Ecole Polytechnique de l'Université de Nantes (EPUN), and Université de Nantes (UN)-Université de Nantes (UN)
Subjects: Models, Molecular, Stereochemistry, Antigen presentation, Receptors, Antigen, T-Cell, Antigen-Presenting Cells, Galactosylceramides, 010402 general chemistry, 01 natural sciences, Cell Line, Mice, Structure-Activity Relationship, Th2 Cells, Immune system, Adjuvants, Immunologic, Species Specificity, Antigen, In vivo, Drug Discovery, Animals, Humans, Structure–activity relationship, ComputingMilieux_MISCELLANEOUS, biology, [CHIM.ORGA]Chemical Sciences/Organic chemistry, Protein Stability, 010405 organic chemistry, Chemistry, Hydrogen Bonding, Stereoisomerism, Th1 Cells, In vitro, 0104 chemical sciences, Mice, Inbred C57BL, Biochemistry, CD1D, biology.protein, Natural Killer T-Cells, Molecular Medicine, Female, Antigens, CD1d, Cell activation
Abstract: We propose here the synthesis and biological evaluation of 3,4-dideoxy-GalCer derivatives. The absence of the 3- and 4-hydroxyls on the sphingoid base is combined with the introduction of mono or difluoro substituent at C3 (analogues 8 and 9, respectively) to evaluate their effect on the stability of the ternary CD1d/GalCer/TCR complex which strongly modulate the immune responses. Biological evaluations were performed in vitro on human cells and in vivo in mice and results discussed with support of modeling studies. The fluoro 3,4-dideoxy-GalCer analogues appears as partial agonists compared to KRN7000 for iNKT cell activation, inducing T(H)1 or T(H)2 biases that strongly depend of the mode of antigen presentation, including human vs mouse differences. We evidenced that if a sole fluorine atom is not able to balance the loss of the 3-OH, the presence of a difluorine group at C3 of the sphingosine can significantly restore human iNKT activation.
Published: 2012

34. Synthesis and Biological Evaluation of 4′-C,3′-O-Propylene-Linked Bicyclic Nucleosides

Author: Julie Hunault, Adjou Ané, Virginie Silvestre, Nathalie Bourgougnon, Jacques Lebreton, Raymond F. Schinazi, Muriel Pipelier, Jong-Hyun Cho, Mervi Detorio, Valérie Fargeas, Virginie Blot, Didier Dubreuil, Wilfried Hatton, Maxim Egorov, Christophe Len, Tami R. McBrayer, Chimie Et Interdisciplinarité : Synthèse, Analyse, Modélisation (CEISAM), Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Unité de Biotechnologie, Biocatalyse et Biorégulation (U3B), Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Synthèse Organique (Hétérochimie organique, organoéléments et matériaux) (LSOHOOM), Laboratoire de Biotechnologie et Chimie Marines (LBCM), Université de Bretagne Sud (UBS)-Université de Brest (UBO)-Institut Universitaire Européen de la Mer (IUEM), and Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Glycosylation, Bicyclic molecule, Pyrimidine, 010405 organic chemistry, Chemistry, Stereochemistry, Organic Chemistry, Phosphoramidate, Prodrug, 010402 general chemistry, Metathesis, [SDV.MP.BAC]Life Sciences [q-bio]/Microbiology and Parasitology/Bacteriology, 01 natural sciences, Article, 0104 chemical sciences, Nucleobase, chemistry.chemical_compound, Physical and Theoretical Chemistry, Cytotoxicity, ComputingMilieux_MISCELLANEOUS
Abstract: A set of pyrimidine nucleosides fused with a 4′-C,3′-O-propylene bridge was successfully synthesised in 12 steps from 1,2:5,6-di-O-isopropylidene-α-d-glucofuranose, an inexpensive starting material, based on a ring-closing metathesis (RCM) reaction followed by Vorbrüggen-type nucleobase coupling. Antiviral and cytotoxicity activities of the targeted modified nucleosides, as well as their phosphoramidate prodrugs, are described.
Published: 2011

35. Synthesis of Carbon E,E-Diene Chain-Linked Dinucleotide Analogues

Author: Adjou Ané, Jacques Lebreton, Valérie Fargeas, Didier Dubreuil, Laboratoire de Synthèse Organique (Hétérochimie organique, organoéléments et matériaux) (LSOHOOM), Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS), Chimie Et Interdisciplinarité : Synthèse, Analyse, Modélisation (CEISAM), Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), and Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)
Subjects: 010405 organic chemistry, Stereochemistry, Dimer, Organic Chemistry, chemistry.chemical_element, 010402 general chemistry, 01 natural sciences, Coupling reaction, 0104 chemical sciences, 3. Good health, Nucleobase, chemistry.chemical_compound, chemistry, [CHIM]Chemical Sciences, Organic chemistry, Antisense Agents, Thymidine, Carbon
Abstract: The synthesis of a dinucleotide thymidine-thymidine linked by a carbon E,E-diene chain is described. This dimer is synthesized by a coupling reaction between an (E)-vinylstannane and an (E)-iodovinyl partner prepared from acetylenic parents, which are both available from thymidine in six and five steps, respectively. In addition, a new efficient access to 3'-C-formyl thymidine is presented.
Published: 2009

36. Focus on the Controversial Activation of Human iNKT Cells by 4-Deoxy Analogue of KRN7000

Author: Virginie Blot, Julie Hunault, Jacques Le Pendu, Didier Dubreuil, Anne-Laure Turcot-Dubois, Laurent Micouin, Marc Bonneville, Vivien Lacone, Thomas Lecourt, Séverine Marionneau, Jézabelle Rocher, Muriel Pipelier, Monique Clément, and J.Y. Douillard
Subjects: Galactosylceramides, Stimulation, Lymphocyte Activation, Natural killer cell, Interferon-gamma, Mice, Structure-Activity Relationship, chemistry.chemical_compound, Glycolipid, Adjuvants, Immunologic, In vivo, Drug Discovery, medicine, Animals, Humans, Sphingosine, Tumor Necrosis Factor-alpha, Chemistry, Biological activity, Sphingolipid, In vitro, Cell biology, medicine.anatomical_structure, Biochemistry, Natural Killer T-Cells, Molecular Medicine, Interleukin-4
Abstract: 4-Deoxy-alpha-GalCer analogues are considered weaker agonists than KRN7000 for the stimulation of human iNKT cells, but this remains strongly debated. In this work, we described a strategy toward 4-deoxy-alpha-GalCers with, as a key step, a metathesis reaction allowing sphingosine modifications from a single ethylenic alpha-galactoside precursor. The 4-deoxy-KRN7000 derivative 2, described here, induced potent cytokinic responses, comparable to those of KRN7000, both from human iNKT cells in vitro and from their murine counterpart in vivo.
Published: 2009

37. Bolometers at CEA: ARTEMIS and beyond

Author: B. Horeau, P. O. Lagage, C. Delisle, D. Rabanus, J. Relland, O. Boulade, C. De Breuck, Pascal André, E. Doumayrou, L. Rodriguez, Didier Dubreuil, V. Minier, E. Ercolani, P. Gallais, J. Martignac, M. Talvard, Vincent Reveret, G. Willmann, François Visticot, E. Pantin, P. Agnèse, B. Leriche, M. Lortholary, and Y. Le-Pennec
Subjects: Physics, business.industry, Bolometer, Detector, General Engineering, Astronomy and Astrophysics, Astrophysics, Cryogenics, Space exploration, law.invention, Telescope, Space and Planetary Science, law, Electronics, Aerospace engineering, business
Abstract: ArTeMiS is a bolometer camera that will be installed at the APEX submillimeter telescope in Chile in 2010. This instrument will be a powerful tool for scientists with its three focal planes that will operate simultaneously in background limited conditions at 200, 350 and 450 microns (5760 pixels in total). A prototype called p-ArTeMiS has been tested at APEX in 2007 and thanks to its good performances, the team has been able to conduct scientific projects in star formation and on debris disks. This paper summarises the details of the ArTeMiS project, with a description of the detectors, the optics, the cryogenics and the electronics. We will also present the undergoing studies at CEA on detectors for the future submillimeter space missions.
Published: 2009

38. Synthesis of Polyhydroxylated Pyrano-Pyrrole Derivatives from Carbohydrate Precursors

Author: Michel Evain, Ané Adjou, Sebastien Naud, François Huet, Anne-Marie Aubertin, Guillaume Viault, Muriel Pipelier, Didier Dubreuil, Stéphanie Legoupy, Laboratoire de Synthèse Organique (Hétérochimie organique, organoéléments et matériaux) (LSOHOOM), Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS), Unité de chimie organique moléculaire et macromoléculaire (UCO2M), Le Mans Université (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Institut des Matériaux Jean Rouxel (IMN), Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Ecole Polytechnique de l'Université de Nantes (EPUN), Université de Nantes (UN)-Université de Nantes (UN), Chimie Et Interdisciplinarité : Synthèse, Analyse, Modélisation (CEISAM), Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), and Le Mans Université (UM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [CHIM.ORGA]Chemical Sciences/Organic chemistry, 010405 organic chemistry, Stereochemistry, Organic Chemistry, General Medicine, Carbohydrate, Ring (chemistry), 010402 general chemistry, 01 natural sciences, Cycloaddition, Pyrrole derivatives, 0104 chemical sciences, Pyridazine, chemistry.chemical_compound, chemistry, Intramolecular force, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Organic chemistry, Physical and Theoretical Chemistry, ComputingMilieux_MISCELLANEOUS, Pyrrole
Abstract: The efficient synthesis of novel polyhydroxy-tetrahydropyrano-pyrroles from acetylenic carbohydrate precursors in three to four steps is described. The methodology involves, as key steps, the ring contraction of pyridazine intermediates obtained by an inverse-demand Diels–Alder reaction and subsequent intramolecular lactonization. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Published: 2007

39. Synthesis of Novel Polyhydroxylated Tetrahydropyranopyrroles

Author: Christophe Chaumette, Sebastien Naud, Guillaume Viault, Stéphanie Legoupy, Didier Dubreuil, Muriel Pipelier, François Huet, Chimie Et Interdisciplinarité : Synthèse, Analyse, Modélisation (CEISAM), Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), and Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)
Subjects: Stereochemistry, Chemistry, 020209 energy, Organic Chemistry, General Medicine, 02 engineering and technology, Ring (chemistry), 010402 general chemistry, 01 natural sciences, 0104 chemical sciences, Pyridazine, chemistry.chemical_compound, Computational chemistry, 0202 electrical engineering, electronic engineering, information engineering, Stereoselectivity
Abstract: The stereoselective access to original polyhydroxylated tetrahydropyranopyrroles is described. The key steps involve an inverse-demand Diels-Alder reaction and a ring contraction of a pyridazine heterocycle.
Published: 2007

40. The Mid-Infrared Instrument for the James Webb Space Telescope, III: MIRIM, The MIRI Imager

Author: G. Olofsson, F. Gougnaud, Karl D. Gordon, Samuel Ronayette, C. H. R. Chen, Didier Leboeuf, M. García-Marín, Etienne Renotte, Y. Longval, Martyn Wells, Tom Ray, Daniel Dicken, P. Bouchet, Pierre Guillard, Kay Justtanont, Alistair Glasse, Oliver Krause, J. Sykes, P. O. Lagage, E. Bauwens, Ph. Galdemard, M. P. Thelen, Jean-Michel Reess, Laurent Martin, Emmanuel Mazy, Ö. H. Detre, Silvia Scheithauer, David W. Wright, R. Gastaud, J. L. Auguères, Jérôme Amiaux, Michael E. Ressler, J. A. D. L. Blommaert, V. Moreau, Didier Dubreuil, G. S. Wright, S. Salasca, Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Physics, Astrophysics, and Astronomy and Astrophysics Research Group
Subjects: Pixel, Spectrometer, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Wavelength range, Low resolution, James Webb Space Telescope, Mid infrared, FOS: Physical sciences, Astronomy and Astrophysics, Operational requirements, Space and Planetary Science, Mechanical design, Environmental science, Astrophysics - Instrumentation and Methods for Astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), Remote sensing
Abstract: In this article, we describe the MIRI Imager module (MIRIM), which provides broad-band imaging in the 5 - 27 microns wavelength range for the James Webb Space Telescope. The imager has a 0"11 pixel scale and a total unobstructed view of 74"x113". The remainder of its nominal 113"x113" field is occupied by the coronagraphs and the low resolution spectrometer. We present the instrument optical and mechanical design. We show that the test data, as measured during the test campaigns undertaken at CEA-Saclay, at the Rutherford Appleton Laboratory, and at the NASA Goddard Space Flight Center, indicate that the instrument complies with its design requirements and goals. We also discuss the operational requirements (multiple dithers and exposures) needed for optimal scientific utilization of the MIRIM., Comment: 29 pages, 9 figures
Published: 2015

41. Iterative design of a helically folded aromatic oligoamide sequence for the selective encapsulation of fructose

Author: Cameron D. Mackereth, Yann Ferrand, Brice Kauffmann, Didier Dubreuil, Michel Laguerre, Ivan Huc, Guillaume Lautrette, Nagula Chandramouli, Chimie et Biologie des Membranes et des Nanoobjets (CBMN), Université de Bordeaux (UB)-École Nationale d'Ingénieurs des Travaux Agricoles - Bordeaux (ENITAB)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Chimie Et Interdisciplinarité : Synthèse, Analyse, Modélisation (CEISAM), Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), and Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)
Subjects: Models, Molecular, Modular structure, Iterative design, Chemistry, General Chemical Engineering, Spectrum Analysis, Molecular Conformation, Fructose, Hydrogen Bonding, General Chemistry, Oligomer, Combinatorial chemistry, Amides, Encapsulation (networking), chemistry.chemical_compound, Organic chemistry, [CHIM]Chemical Sciences
Abstract: The ab initio design of synthetic molecular receptors for a specific biomolecular guest remains an elusive objective, particularly for targets such as monosaccharides, which have very close structural analogues. Here we report a powerful approach to produce receptors with very high selectivity for specific monosaccharides and, as a demonstration, we develop a foldamer that selectively encapsulates fructose. The approach uses an iterative design process that exploits the modular structure of folded synthetic oligomer sequences in conjunction with molecular modelling and structural characterization to inform subsequent refinements. Starting from a first-principles design taking size, shape and hydrogen-bonding ability into account and using the high predictability of aromatic oligoamide foldamer conformations and their propensity to crystallize, a sequence that binds to β-D-fructopyranose in organic solvents with atomic-scale complementarity was obtained in just a few iterative modifications. This scheme, which mimics the adaptable construction of biopolymers from a limited number of monomer units, provides a general protocol for the development of selective receptors.
Published: 2015

42. Unusual anomeric rearrangement of para-nitrobenzoylxanthate d-glycosides: a new direct stereoselective access to α-thioglycosides from pyranose sugars

Author: Anirban Kar, Sandrine Vidot, Muriel Pipelier, Didier Dubreuil, Vivien Lacône, Solen Josse, Sebastien Naud, Adjou Ané, and Anaïs Fournial
Subjects: chemistry.chemical_classification, Carbon disulfide, Anomer, Chemistry, Stereochemistry, Organic Chemistry, Glycoside, Biochemistry, Sodium hydride, chemistry.chemical_compound, Pyranose, Yield (chemistry), Drug Discovery, Stereoselectivity, Lewis acids and bases
Abstract: A mild and general procedure for the synthesis of α-thioglycosides from glycopyranoses is described. The method involves the treatment of pyranose reductive sugar with sodium hydride, carbon disulfide, and p-nitrobenzoyl chloride, as a key step, to yield p-nitrobenzoyl-α- d -thioglycopyranose intermediates with high stereoselectivity, in a one-pot-two-step process. The interest of the strategy highlights a direct stereoselective access to ether-protected 1-thiol-α- d -glycopyranose derivatives (Gal, Glc, and Man) from pyranoses in the absence of anomeric ‘Lewis acid’ promoters.
Published: 2006

43. Synthesis of mono- and polyhydroxylated cyclobutane nucleoside analogs

Author: Yoann Marsac, Anne-Marie Aubertin, Stéphanie Legoupy, Muriel Pipelier, François Huet, Rachid Benhida, Arnaud Nourry, Didier Dubreuil, and Nathalie Bourgougnon
Subjects: Cyclobutene, Nucleoside analogue, Stereochemistry, Organic Chemistry, Biochemistry, Cyclobutane, chemistry.chemical_compound, Hydroboration, chemistry, Dihydroxylation, Drug Discovery, medicine, Organic chemistry, Mitsunobu reaction, medicine.drug
Abstract: Enantiomerically enriched cyclobutene compounds 13 and 24 are good precursors of several cyclobutane nucleoside analogs. The synthetic ways involve, in the key step, either hydroboration or dihydroxylation.
Published: 2005

44. Simultaneous determination of metronidazole and spiramycin I in human plasma, saliva and gingival crevicular fluid by LC–MS/MS

Author: Ivan Brumpt, Cyriaque Sagan, Pierre. P. Poulet, Didier Dubreuil, D. Duffaut, and Arnaud Salvador
Subjects: Saliva, Time Factors, Clinical Biochemistry, Gingiva, Administration, Oral, Pharmaceutical Science, High-performance liquid chromatography, Mass Spectrometry, Analytical Chemistry, Anti-Infective Agents, Liquid chromatography–mass spectrometry, Metronidazole, Drug Discovery, Blood plasma, medicine, Humans, Spectroscopy, Antibacterial agent, Chromatography, Chemistry, Ornidazole, Extraction (chemistry), Spiramycin, Reproducibility of Results, Aminoglycosides, Calibration, Chronic Disease, Periapical Periodontitis, Chromatography, Liquid, medicine.drug
Abstract: An analytical validation of a new liquid chromatographic-mass spectrometric (LC-MS/MS) method for simultaneous determination of metronidazole and spiramycin I concentrations in human plasma, saliva and gingival crevicular fluid (GCF) is presented. Ornidazole was used as an internal standard, and sample pre-treatment consisted of a liquid-liquid extraction. Chromatographic separation was achieved on a 5 microm Kromasil C18 column (150 mm x 4.6 mm i.d., particle size 5 microm), with a gradient using acetonitrile, water and formic acid at a flow rate of 0.9 ml/min. The methods were validated in terms of intra- and inter-batch precision (
Published: 2005

45. Concomitant ring contraction cyclization strategy for the synthesis of novel 4-oxo-4,5-dihydro-pyrroloquinolines

Author: Jean Paul Pradere, Stephane Sabelle, Hicham Bakkali, G. T. Manh, Muriel Pipelier, Remy Tuloup, Lucie Maingot, Didier Dubreuil, and Uday Joshi
Subjects: Contraction (grammar), Chemistry, Stereochemistry, Concomitant, Organic Chemistry, Drug Discovery, General Medicine, Biochemistry
Abstract: The synthesis of novel substituted pyrroloquinolinones is described by concomitant ring contraction cyclization form 2-(2-amino-5-nitro-phenyl)-[4 H ]-1,3-thiazines, which were derived from N -substituted 5-nitro-anthranilonitrile. An easy access to novel 4-thiono-1,4-dihydro-1,3-quinazoline heterocycles is also mentioned.
Published: 2004

46. Advanced preparation of functionalized triarylbismuths and triheteroaryl-bismuths: new scope and alternatives

Author: Didier Dubreuil, Sylvie Condon, Virginie Blot, Christophe Aube, Christophe Pichon, Muriel Pipelier, Eric Léonel, Karène Urgin, and Christine Thobie-Gautier
Subjects: Bismuth chloride, chemistry.chemical_compound, chemistry, Scope (project management), Reagent, Organic Chemistry, Drug Discovery, Biochemistry, Combinatorial chemistry
Abstract: A simple and versatile novel method for the preparation of triaryl- and trihetero-arylbismuths bearing electron withdrawing or electron donating groups was accomplished by the reaction of organozinc reagents with BiCl 3 . Scope and limits of the process are investigated.
Published: 2012

47. SYNTHESIS OF THIAAZAHETEROCYCLE NUCLEOSIDE ANALOGUES

Author: Didier Dubreuil, Muriel Pipelier, Jean-Paul Pradère, A. Ane, M. Thiam, Guillaume Prestat, and Solen Josse
Subjects: Glycosylation, Chemistry, Stereochemistry, Nucleosides, General Medicine, Biochemistry, Modified nucleosides, Thiazoles, Models, Chemical, Intramolecular force, Genetics, Molecular Medicine, Base (exponentiation), Nucleoside
Abstract: The syntheses of thiazinone, thiazinedione and thiazolinone base modified nucleoside analogues have been discussed in both the deoxy- and ribosyl series. Both inter- and intramolecular N-glycosylations were evaluated.
Published: 2002

48. Electrochemical reduction of substituted pyridazines: a new access to activated pyrroles

Author: J.-P. Pradere, G. T. Manh, R. Hazard, Didier Dubreuil, M. Thiam, Loïc Toupet, and André Tallec
Subjects: General Chemical Engineering, Disproportionation, Buffer solution, Electrochemistry, Medicinal chemistry, Acetic acid, chemistry.chemical_compound, chemistry, X-ray crystallography, Polar effect, Chemical reduction, Organic chemistry, Pyrrole
Abstract: The electrochemical two electron reduction of pyridazines, substituted by electron withdrawing groups, primarily lead to their corresponding 1,2-dihydro-derivatives. Depending on the nature of the ring substitution, these intermediates can either rearrange into 1,4-dihydro-pyridazines, or undergo electrochemical reduction to give rise to activated pyrroles by a ring contraction reaction with extrusion of nitrogen. Another way of access to the latter has been achieved by a disproportionation reaction of 1,2-dihydro-pyridazines, leading directly to the expected pyrroles and recovery of 50% of pyridazines.
Published: 2002

49. Reactivity of 1,1′-thiocarbonyldiimidazole with glycosides: a novel and efficient glycosidic activation

Author: Solen Josse, Julien Le Gal, Jean-Paul Pradère, Muriel Pipelier, Didier Dubreuil, and Rachid Benhida
Subjects: chemistry.chemical_classification, Anomer, Glycosylation, Chemistry, Stereochemistry, Organic Chemistry, Glycoside, Glycosidic bond, Biochemistry, Reducing sugar, chemistry.chemical_compound, Drug Discovery, Organic chemistry, Reactivity (chemistry)
Abstract: The synthesis of monoglycosyl imidazoles and 1,1′-di- O -glycosides is described by direct glycosylation process from reducing sugar in the presence of 1,1′-thiocarbonyldiimidazole. Novel anomeric groups as 1- O -(imidazolyl)thiocarbonyl and 1- O -(imidazolyl)carbonyl are presented as potent glycosidic activators.
Published: 2002

50. A new technique of characterization of the intrapixel response of astronomical detectors

Author: Samuel Ronayette, V. Moreau, Guillaume Druart, Didier Dubreuil, C. Ketchazo, Olivier Boulade, S. Derelle, Michel Berthé, Nicolas Guérineau, Laurent M. Mugnier, and T. Viale
Subjects: Physics, Photometry (optics), Test bench, Cardinal point, Optics, Pixel, business.industry, Detector, Talbot effect, Grating, Inverse problem, business
Abstract: This paper is devoted to the presentation of a new technique of characterization of the Intra-Pixel Sensitivity Variations (IPSVs) of astronomical detectors. The IPSV is the spatial variation of the sensitivity within a pixel and it was demonstrated that this variation can contribute to the instrument global error. Then IPSV has not to be neglected especially in the case of under-sampled instruments for high quality imaging and accurate photometry. The common approaches to measure the IPSV consist in determining the pixel response function (PRF) by scanning an optical probe through the detector. These approaches require high-aperture optics, high precision mechanical devices and are time consuming. The original approach we will present in this paper consists in projecting high-resolution periodic patterns onto the whole sensor without classic optics but using the self-imaging property (the Talbot effect) of a Continuously Self Imaging Grating (CSIG) illuminated by a plane wave. This paper describes the test bench and its design rules. The methodology of the measurement is also presented. Two measurement procedures are available: global and local. In the global procedure, the mean PRF corresponding to the whole Focal Plane Array (FPA) or a sub-area of the FPA is evaluated. The results obtained applying this procedure on e2v CCD 204 are presented and discussed in detail. In the local procedure, a CSIG is moved in front of each pixel and a pixel PRF is reconstructed by resolving the inverse problem. The local procedure is presented and validated by simulations.
Published: 2014

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