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51. Organocatalytic enantio- and diastereoselective 1,3-dipolar cycloaddition between alanine-derived ketonitrones and E-crotonaldehyde: efficiency and full stereochemical studies

Author

Jérôme Lhoste, Arnaud Martel, Mathieu Y. Laurent, Gilles Dujardin, Khalid B. Selim, Anne Beauchard, Institut des Molécules et Matériaux du Mans (IMMM), Le Mans Université (UM)-Centre National de la Recherche Scientifique (CNRS), Department of Pharmaceutical Organic Chemistry, Mansoura University [Egypt], and Le Mans Université (UM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Alanine, [CHIM.ORGA]Chemical Sciences/Organic chemistry, 010405 organic chemistry, Chemistry, Stereochemistry, Imidazolidinone, Organic Chemistry, Absolute configuration, 010402 general chemistry, 01 natural sciences, Catalysis, 0104 chemical sciences, Inorganic Chemistry, chemistry.chemical_compound, Yield (chemistry), 1,3-Dipolar cycloaddition, Stereoselectivity, Physical and Theoretical Chemistry, Crotonaldehyde, ComputingMilieux_MISCELLANEOUS
Abstract

Highly enantio- and exo-selective 1,3-dipolar cycloadditions of alanine-derived ketonitrones to E-crotonaldehyde could be realized in a good yield by the use of a chiral imidazolidinone salt without the addition of water. The origin of the stereoselectivity in the reaction was discussed and the absolute configuration of the cycloadduct determined unambiguously.

Published
2012

52. ChemInform Abstract: Synthesis of SF5-Substituted Isoxazolidines Using 1,3-Dipolar Cycloaddition Reactions of Nitrones with Pentafluorosulfanyl Acrylic Esters and Amides

Author

Mathieu Y. Laurent, Xavier Pannecoucke, Ewelina Falkowska, Vincent Tognetti, Philippe Jubault, Laurent Joubert, and Jean-Philippe Bouillon

Subjects
Chemistry, 1,3-Dipolar cycloaddition, Regioselectivity, General Medicine, Medicinal chemistry
Abstract

1,3-Dipolar cycloadditions of nitrones with pentafluorosulfanyl-substituted acrylic ester and amides afforded new trisubstituted pentafluorosulfanylated isoxazolidines in moderate yields as 4-SF5-regioisomers. Theoretical calculations were carried out and the regioselectivity could be explained by the fact that the 5-SF5-regioisomer probably undertook a spontaneous degradation in the reaction medium via the loss of pentafluorosulfanyl anion. Diastereoselectivity of the 1,3-dipolar cycloadditions was also assessed according to NMR and X-ray diffraction analysis.

Published
2016

53. New two-step sequence involving a hetero-Diels–Alder and a nonphenolic oxidative coupling reaction: a convergent access to analogs of steganacin

Author

Vivien Stocker, Mathieu Y. Laurent, Robert Dhal, Valéry Momo Temgoua, Gilles Dujardin, Unité de chimie organique moléculaire et macromoléculaire (UCO2M), and Le Mans Université (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)

Subjects
Lignan, Biaryl coupling, Cyclic compound, [CHIM.ORGA]Chemical Sciences/Organic chemistry, 010405 organic chemistry, Stereochemistry, Organic Chemistry, Two step, Steganacin, Sequence (biology), Atroposelectivity, 010402 general chemistry, 01 natural sciences, Biochemistry, 0104 chemical sciences, chemistry.chemical_compound, chemistry, Drug Discovery, Diels alder, Stereoselectivity, Oxidative coupling of methane, ComputingMilieux_MISCELLANEOUS, Hetero-Diels-Alder
Abstract

A new family of analogs of steganacin, an important antimitotic compound, was accessed. It takes advantage of a completely stereoselective sequence of two key steps. The central dihydropyrane core is built by a highly diastereoselective and facially controlled hetero-Diels–Alder reaction. It is followed by a nonphenolic biaryl oxidative coupling with a complete atropo-stereoselectivity. It leads to a quick way to form cyclic biaryl lignans.

Published
2011

56. Variations in national surveillance reporting for Mpox virus: A comparative analysis in 32 countries

Author

Deepkanwar Singh Panag, Nityanand Jain, Dimitra Katagi, Gabriela De Jesus Cipriano Flores, Gabriela Dias Silva Dutra Macedo, Gonzalo Rodrigo Díaz Villa, Mathieu Yèche, Saydi Yusveni Velázquez Mérida, Sreerag Kapparath, Zilfi Sert, and Aigars Reinis

Subjects
case definitions, differences, epidemiology, Monkeypox, mpox, reporting, Public aspects of medicine, RA1-1270
Abstract

ObjectivesCase Reporting and Surveillance (CRS) are crucial to combat the global spread of the Monkeypox virus (Mpox). To support CRS, the World Health Organization (WHO) has released standardized case definitions for suspected, probable, confirmed, and discarded cases. However, these definitions are often subject to localized adaptations by countries leading to heterogeneity in the collected data. Herein, we compared the differences in Mpox case definitions in 32 countries that collectively reported 96% of the global Mpox caseload.MethodsWe extracted information regarding Mpox case definitions issued by the competent authorities in 32 included countries for suspected, probable, confirmed, and discarded cases. All data were gathered from online public sources.ResultsFor confirmed cases, 18 countries (56%) followed WHO guidelines and tested for Mpox using species specific PCR and/or sequencing. For probable and suspected cases, seven and eight countries, respectively were found to have not released definitions in their national documentations. Furthermore, none of the countries completely matched WHO’s criteria for probable and suspected cases. Overlapping amalgamations of the criteria were frequently noticed. Regarding discarded cases, only 13 countries (41%) reported definitions, with only two countries (6%) having definition consistent with WHO guidelines. For case reporting, 12 countries (38%) were found to report both probable and confirmed cases, in line with WHO requirements.ConclusionThe heterogeneity in case definitions and reporting highlights the pressing need for homogenization in implementation of these guidelines. Homogenization would drastically improve data quality and aid data-scientists, epidemiologists, and clinicians to better understand and model the true disease burden in the society, followed by formulation and implementation of targeted interventions to curb the virus spread.

Published
2023
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57. ChemInform Abstract: [3 + 2] Route to Quaternary Oxaprolinol Derivatives as Masked Precursors of Disubstituted β3,β3-Amino Aldehyde

Author

Pavlo Shpak-Kraievskyi, Anne Beauchard, Arnaud Martel, Mathieu Y. Laurent, Gilles Dujardin, and Amelle Mankou Makaya

Subjects
chemistry.chemical_classification, Enantiopure drug, Chemistry, Stereochemistry, General Medicine, Aldehyde
Abstract

A new approach to enantiopure disubstituted oxaprolinol derivatives through diastereoselective [3+2]-cycloaddition of chiral cyclic ketonitrones to electron-rich and electron-poor dipolarophiles is presented.

Published
2015

59. Synthesis of SF5-substituted isoxazolidines using 1,3-dipolar cycloaddition reactions of nitrones with pentafluorosulfanyl acrylic esters and amides

Author

Philippe Jubault, Xavier Pannecoucke, Mathieu Y. Laurent, Laurent Joubert, Jean-Philippe Bouillon, Vincent Tognetti, Ewelina Falkowska, Chimie Organique et Bioorganique : Réactivité et Analyse (COBRA), Institut Normand de Chimie Moléculaire Médicinale et Macromoléculaire (INC3M), Institut de Chimie du CNRS (INC)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Institut de Chimie du CNRS (INC)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie Organique Fine (IRCOF), Université de Rouen Normandie (UNIROUEN), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), 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), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie Organique Fine (IRCOF), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université de Rouen Normandie (UNIROUEN), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), and Le Mans Université (UM)-Centre National de la Recherche Scientifique (CNRS)

Subjects
010405 organic chemistry, [CHIM.ORGA]Chemical Sciences/Organic chemistry, Organic Chemistry, chemistry.chemical_element, Regioselectivity, [CHIM.CATA]Chemical Sciences/Catalysis, [CHIM.THER]Chemical Sciences/Medicinal Chemistry, 010402 general chemistry, 01 natural sciences, Biochemistry, 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, chemistry, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, Drug Discovery, 1,3-Dipolar cycloaddition, Fluorine, Organic chemistry, [CHIM.CHEM]Chemical Sciences/Cheminformatics
Abstract

International audience; 1,3-Dipolar cycloadditions of nitrones with pentafluorosulfanyl-substituted acrylic ester and amides afforded new trisubstituted pentafluorosulfanylated isoxazolidines in moderate yields as 4-SF5-regioisomers. Theoretical calculations were carried out and the regioselectivity could be explained by the fact that the 5-SF5-regioisomer probably undertook a spontaneous degradation in the reaction medium via the loss of pentafluorosulfanyl anion. Diastereoselectivity of the 1,3-dipolar cycloadditions was also assessed according to NMR and X-ray diffraction analysis.

Published
2015

60. A Practical and Cost-Effective Method for the Synthesis of Bicyclo[2.2.2]octane-1,4-dicarboxylic Acid

Author

Mathieu Y. Laurent, Nicolas Le Marquer, Arnaud Martel, Institut des Molécules et Matériaux du Mans (IMMM), and Le Mans Université (UM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
chemistry.chemical_classification, Bicyclic molecule, Organic Chemistry, bicyclo[2.2.2]octane-1, Catalysis, Raney nickel, chemistry.chemical_compound, Dicarboxylic acid, chemistry, Microwave irradiation, 4-dicarboxylic acid - safe - semicarbazone - microwave irradiation - rigid backbone - solid-phase, Organic chemistry, [CHIM]Chemical Sciences, Semicarbazone, Octane
Abstract

International audience; A short and efficient synthesis of bicyclo[2.2.2]octane-1,4-dicarboxylic acid involving the formation of a semicarbazone is developed, and a reproducible protocol for the reduction of this semicarbazone is described. The use of microwaves significantly shortens the duration of the sequence to the diacid compared to the previously described synthetic method. In addition, by shifting from the use of large amounts of Raney nickel to a solid-phase process, both the safety and cost are improved notably.

Published
2015

61. [3+2] Route to Quaternary Oxaprolinol Derivatives as Masked Precursors of Disubstituted β 3 ,β 3 -Amino Aldehyde

Author

Shpak-Kraievskyi, Pavlo, Mankou Makaya, Amelle, Beauchard, Anne, Martel, Arnaud, Laurent, Mathieu Y., Dujardin, Gilles, 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 Molécules et Matériaux du Mans (IMMM), Le Mans Université (UM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and ANR-11-BS07-0005,OXAPROL,Oxaprolines Polyfonctionnelles : Synthèse Asymétrique via Cycloaddition Dipolaire-1,3, Evaluation en tant que Nouveaux Organocatalyseurs et Précurseurs d'Aminoacides Disubstitués et Contraints.(2011)

Subjects
Chemoselectivity, [CHIM.ORGA]Chemical Sciences/Organic chemistry, [CHIM]Chemical Sciences, Asymmetric synthesis, Chiral auxiliaries, Quaternary center, Amino aldehydes, Cycloaddition
Abstract

International audience; Isoxazolidines displaying a quaternary stereocenter were formed starting from functional cyclic ketonitrones through a highly stereocontrolled 1,3‐dipolar cycloaddition. Chemoselective reductive chiral auxiliary removal gives quaternary oxaprolinol derivatives, which were further transformed into dipeptides terminated directly with an aldehyde function.

Published
2015

62. ChemInform Abstract: Asymmetric Access to α-Substituted Functional Aspartic Acid Derivatives by a [3 + 2] Strategy Employing a Chiral Dienophile

Author

Souhir Abid, Jean-François Poisson, Houcine Ammar, Kawther Ben Ayed, Mathieu Y. Laurent, Gilles Dujardin, Sandrine Py, Arnaud Martel, and Anne Beauchard

Subjects
Chemistry, Aspartic acid, General Medicine, Combinatorial chemistry, Cycloaddition
Abstract

The first example of a high facial selective [3 + 2] cycloaddition employing chiral vinyl ethers as dipolarophile and nitrones as dipoles is presented.

Published
2015

63. Crystal structure of N- (dipheny 1)methy 1-3 (S) - [1 (R)-hydroxoethyl] - 4(S)-[2',2'-dimethyI-1'-oxopropyl]-2-azetidinone, C23H27NO3

Author

Bernard Tinant, Mathieu Y. Laurent, and Jacqueline Marchand-Brynaert

Subjects
Inorganic Chemistry, Crystallography, 2-Azetidinone, chemistry.chemical_compound, Chemistry, General Materials Science, Orthorhombic crystal system, Angstrom, Crystal structure, Condensed Matter Physics
Abstract

C23H27NO3, orthorhombic, P2(1)2(1)2(1) (no. 19), a = 6.054(2) angstrom, b = 11.479(5) angstrom, c = 29.210(3) angstrom, V = 2029.9 angstrom(3), Z = 4, R-gt(F) = 0.047, wR(ref)(F-2) = 0.121, T = 125 K.

Published
2006

64. A New Method ofN-Benzhydryl Deprotection in 2-Azetidinone Series

Author

Mathieu Y. Laurent, Marc Belmans, Marcel Cérésiat, Luc Kemps, and Jacqueline Marchand-Brynaert

Subjects
2-Azetidinone, Bromine, Organic Chemistry, chemistry.chemical_element, Halogenation, Catalysis, chemistry.chemical_compound, Hydrolysis, chemistry, Benzophenone, Organic chemistry, Protecting group, Stoichiometry
Abstract

A mild and efficient procedure for the selective cleavage of N-benzhydryl protecting group of beta-lactams is described. The protected 2-azetidinones 4, precursors of carbapenems, were treated with a stoichiometric amount of N-bromosuccinimide and a catalytic amount of bromine under sun light irradiation in CH2Cl2-H2O mixture at 20 degreesC for 3 hours. The N-benzhydrol intermediates 6, which could be isolated, were then hydrolyzed with p-TsOH in aqueous acetone to furnish beta-lactams 7 and benzophenone quantitatively.

Published
2003

65. Clinical management of molecular alterations identified by high throughput sequencing in patients with advanced solid tumors in treatment failure: Real-world data from a French hospital

Author

Sandra Pinet, Stéphanie Durand, Alexandre Perani, Léa Darnaud, Fifame Amadjikpe, Mathieu Yon, Tiffany Darbas, Alain Vergnenegre, Thomas Egenod, Yannick Simonneau, Valérie Le Brun-Ly, Julia Pestre, Laurence Venat, Frédéric Thuillier, Alain Chaunavel, Mathilde Duchesne, Véronique Fermeaux, Anne Guyot, Sylvain Lacorre, Barbara Bessette, Fabrice Lalloué, Karine Durand, and Elise Deluche

Subjects
cancer, FoundationOne CDx, next-generation sequencing, liquid biopsy, targeted therapy, precision oncology, Neoplasms. Tumors. Oncology. Including cancer and carcinogens, RC254-282
Abstract

BackgroundIn the context of personalized medicine, screening patients to identify targetable molecular alterations is essential for therapeutic decisions such as inclusion in clinical trials, early access to therapies, or compassionate treatment. The objective of this study was to determine the real-world impact of routine incorporation of FoundationOne analysis in cancers with a poor prognosis and limited treatment options, or in those progressing after at least one course of standard therapy.MethodsA FoundationOneCDx panel for solid tumor or liquid biopsy samples was offered to 204 eligible patients.ResultsSamples from 150 patients were processed for genomic testing, with a data acquisition success rate of 93%. The analysis identified 2419 gene alterations, with a median of 11 alterations per tumor (range, 0–86). The most common or likely pathogenic variants were on TP53, TERT, PI3KCA, CDKN2A/B, KRAS, CCDN1, FGF19, FGF3, and SMAD4. The median tumor mutation burden was three mutations/Mb (range, 0–117) in 143 patients with available data. Of 150 patients with known or likely pathogenic actionable alterations, 13 (8.6%) received matched targeted therapy. Sixty-nine patients underwent Molecular Tumor Board, which resulted in recommendations in 60 cases. Treatment with genotype-directed therapy had no impact on overall survival (13 months vs. 14 months; p = 0.95; hazard ratio = 1.04 (95% confidence interval, 0.48–2.26)].ConclusionsThis study highlights that an organized center with a Multidisciplinary Molecular Tumor Board and an NGS screening system can obtain satisfactory results comparable with those of large centers for including patients in clinical trials.

Published
2023
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66. ChemInform Abstract: Enantioselective Ruthenium-Catalyzed 1,3-Dipolar Cycloadditions Between C-Carboalkoxy Ketonitrones and Methacrolein: Solvent Effect on Reaction Selectivity and Its Rational

Author

Sandrine Py, Gilles Dujardin, Mathieu Y. Laurent, Jérôme Lhoste, Arnaud Martel, and Khalid B. Selim

Subjects
chemistry.chemical_compound, chemistry, Enantioselective synthesis, Organic chemistry, chemistry.chemical_element, Methacrolein, General Medicine, Solvent effects, Selectivity, Catalysis, Ruthenium
Abstract

In the presence of the Ru catalyst (RUC), ketonitrones of type (I) are found to react with methacrolein with high regio-, diastereo-, and enantioselectivity.

Published
2014

67. ChemInform Abstract: Asymmetric Synthesis of α,α-Disubstituted Amino Acids by Cycloaddition of (E)-Ketonitrones with Vinyl Ethers

Author

Gilles Dujardin, Pavlo Shpak-Kraievskyi, Jean-François Poisson, Arnaud Martel, Sandrine Py, Pascale Cividino, Mathieu Y. Laurent, X. M. Zhang, Département de Chimie Moléculaire - Synthèse Et Réactivité en Chimie Organique (DCM - SeRCO), Département de Chimie Moléculaire (DCM), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Joseph Fourier - Grenoble 1 (UJF), 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 Molécules et Matériaux du Mans (IMMM), Le Mans Université (UM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), ANR-11-BS07-0005,OXAPROL,Oxaprolines Polyfonctionnelles : Synthèse Asymétrique via Cycloaddition Dipolaire-1,3, Evaluation en tant que Nouveaux Organocatalyseurs et Précurseurs d'Aminoacides Disubstitués et Contraints.(2011), Département de Chimie Moléculaire - Synthèse Et Réactivité en Chimie Organique (SeRCO ), Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut de Chimie Moléculaire de Grenoble (ICMG), and Le Mans Université (UM)-Centre National de la Recherche Scientifique (CNRS)

Subjects
chemistry.chemical_classification, Chiral auxiliary, 010405 organic chemistry, Chemistry, Enantioselective synthesis, General Medicine, 010402 general chemistry, 01 natural sciences, Cycloaddition, 0104 chemical sciences, Amino acid, chemistry.chemical_compound, Nitrogen atom, Organic chemistry, [CHIM]Chemical Sciences, Stereoselectivity, ComputingMilieux_MISCELLANEOUS
Abstract

The stereoselectivity of the 1,3-dipolar cycloaddition of (E)-ketonitrones (I) bearing a chiral auxiliary on the nitrogen atom with vinyl ethers is studied.

Published
2014

68. Asymmetric Access to α-Substituted Functional Aspartic Acid Derivatives by a [3+2] Strategy Employing a Chiral Dienophile

Author

Ben Ayed, Kawther, Beauchard, Anne, Poisson, Jean-François, Py, Sandrine, Laurent, Mathieu Y., Martel, Arnaud, Ammar, Houcine, Abid, Souhir, Dujardin, Gilles, 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), Département de Chimie Moléculaire - Synthèse Et Réactivité en Chimie Organique (DCM - SeRCO), Département de Chimie Moléculaire (DCM), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Joseph Fourier - Grenoble 1 (UJF), 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), Université de Sfax - University of Sfax, ANR-11-BS07-0005,OXAPROL,Oxaprolines Polyfonctionnelles : Synthèse Asymétrique via Cycloaddition Dipolaire-1,3, Evaluation en tant que Nouveaux Organocatalyseurs et Précurseurs d'Aminoacides Disubstitués et Contraints.(2011), Le Mans Université (UM)-Centre National de la Recherche Scientifique (CNRS), Département de Chimie Moléculaire - Synthèse Et Réactivité en Chimie Organique (SeRCO ), and Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut de Chimie Moléculaire de Grenoble (ICMG)

Subjects
[CHIM]Chemical Sciences, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2014

69. Enantioselective Ruthenium-Catalyzed 1,3-Dipolar Cycloadditions between C -Carboalkoxy Ketonitrones and Methacrolein: Solvent Effect on Reaction Selectivity and Its Rational

Author

Jérôme Lhoste, Gilles Dujardin, Arnaud Martel, Mathieu Y. Laurent, Sandrine Py, Khalid B. Selim, LUNAM - Institut des Molécules et Matériaux du Mans, Institut des Molécules et Matériaux du Mans (IMMM), Le Mans Université (UM)-Centre National de la Recherche Scientifique (CNRS), Département de Chimie Moléculaire - Synthèse Et Réactivité en Chimie Organique (SeRCO ), Département de Chimie Moléculaire (DCM), Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut de Chimie Moléculaire de Grenoble (ICMG), ANR-11-BS07-0005,OXAPROL,Oxaprolines Polyfonctionnelles : Synthèse Asymétrique via Cycloaddition Dipolaire-1,3, Evaluation en tant que Nouveaux Organocatalyseurs et Précurseurs d'Aminoacides Disubstitués et Contraints.(2011), Le Mans Université (UM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Département de Chimie Moléculaire - Synthèse Et Réactivité en Chimie Organique (DCM - SeRCO), and Université Joseph Fourier - Grenoble 1 (UJF)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Organic Chemistry, Enantioselective synthesis, chemistry.chemical_element, Methacrolein, Combinatorial chemistry, Cycloaddition, Ruthenium, Solvent, chemistry.chemical_compound, chemistry, Organic chemistry, [CHIM]Chemical Sciences, Lewis acids and bases, Solvent effects, Selectivity
Abstract

International audience; A catalytic 1,3-dipolar cycloaddition between carboalkoxy ketonitrones and methacrolein under the effect of chiral ruthenium Lewis acid (R,R-1) was developed with high regio-, diastereo-, and enantiocontrol. The diastereochemical outcome of the cycloaddition reaction is marked by a significant solvent effect, and a divergent endo or exo control can be tuned by an appropriate choice of both the solvent and the N- and O-substituents of the ketonitrone. A rationale of the solvent effect, based on the computational study of the interactions between the methacrolein–Ru complex and its counteranion (SbF6–), is proposed to explain the selectivities obtained.

Published
2014

70. Asymmetric Synthesis of α,α-Disubstituted Amino Acids by Cycloaddition of ( E )-Ketonitrones with Vinyl Ethers

Author

Pavlo Shpak-Kraievskyi, Arnaud Martel, Jean-François Poisson, Gilles Dujardin, Mathieu Y. Laurent, Pascale Cividino, X. M. Zhang, Sandrine Py, Département de Chimie Moléculaire - Synthèse Et Réactivité en Chimie Organique (DCM - SeRCO), Département de Chimie Moléculaire (DCM), Université Joseph Fourier - Grenoble 1 (UJF)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut de Chimie du CNRS (INC)-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 Molécules et Matériaux du Mans (IMMM), Le Mans Université (UM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), ANR-11-BS07-0005,OXAPROL,Oxaprolines Polyfonctionnelles : Synthèse Asymétrique via Cycloaddition Dipolaire-1,3, Evaluation en tant que Nouveaux Organocatalyseurs et Précurseurs d'Aminoacides Disubstitués et Contraints.(2011), Département de Chimie Moléculaire - Synthèse Et Réactivité en Chimie Organique (SeRCO ), Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut de Chimie Moléculaire de Grenoble (ICMG), and Le Mans Université (UM)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Vinyl Compounds, Stereochemistry, 010402 general chemistry, 01 natural sciences, Biochemistry, chemistry.chemical_compound, [CHIM]Chemical Sciences, Physical and Theoretical Chemistry, Amino Acids, ComputingMilieux_MISCELLANEOUS, chemistry.chemical_classification, Chiral auxiliary, Cycloaddition Reaction, Molecular Structure, 010405 organic chemistry, Organic Chemistry, Enantioselective synthesis, Regioselectivity, Stereoisomerism, Cycloaddition, 0104 chemical sciences, Amino acid, Enantiopure drug, chemistry, Nitrogen atom, Cyclization
Abstract

Original acyclic (E)-α,α-dialkylketonitrones bearing a chiral auxiliary on their nitrogen atom were synthesized and successfully employed for the asymmetric synthesis of α,α-disubstituted amino acids using regio- and stereocontrolled 1,3-dipolar cycloaddition reactions with vinyl ethers. N-Glycosyl chiral auxiliaries were found to provide excellent exo- and π-facial stereocontrol. The obtained enantiopure cycloadducts were selectively transformed into functional α,α-disubstituted amino acids and related β-peptides through the highly regioselective opening of an intermediate quaternary anhydride.

Published
2014

71. A Practical Synthesis of para Di- and Mono-Substituted Benzhydrylamines from Benzhydrol Precursors

Author

Mathieu Y. Laurent and Jacqueline Marchand-Brynaert

Subjects
Chiral column chromatography, Carbamate, Chemistry, medicine.medical_treatment, Organic Chemistry, medicine, Organic chemistry, Basic hydrolysis, Catalysis
Abstract

A series of para-substituted benzhydrylamines 6 were obtained by substitution of the corresponding benzhydrol precursors 1 with phenyl carbamate 2 under acidic conditions, followed by basic hydrolysis of the carbamate intermediates 3. One unsymmetrical intermediate 3i has been resolved by preparative chiral chromatography. Subsequent deprotection of the carbamate function led to the recovery of enantiomerically pure (+)- and (-)-4-chlorobenzhydryl amines.

Published
2000

72. Calpainopathy in Chile, first cases reported

Author

Bevilacqua, J., primary, Mathieu, Y., additional, Krahn, M., additional, Bartoli, M., additional, Castiglioni, C., additional, Kleinsteuber, K., additional, Díaz, J., additional, Puppo, F., additional, Cerino, M., additional, Courrier, S., additional, Gorokhova, S., additional, Miranda, N., additional, Trangulao, A., additional, González-Hormazábal, P., additional, Avaria, M., additional, Urtizberea, J., additional, Caviedes, P., additional, Jara, L., additional, and Levy, N., additional

Published
2016
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74. Crystal structure of N-(diphenyl)methyl-N-(3′,3′-dimethyl-2′-oxo)butyl- 2(R),3(R)-epoxybutyramide, C23H27NO3

Author

Mathieu Y. Laurent, Jacqueline Marchand-Brynaert, and Bernard Tinant

Subjects
Inorganic Chemistry, Crystallography, Chemistry, QD901-999, General Materials Science, Beta (velocity), Crystal structure, Angstrom, Condensed Matter Physics, Monoclinic crystal system
Abstract

C23H27NO3, monoclinic, P1211 (no. 4), a = 8.669(3) Å, b = 22.880(5)Å, c = 10.220(3)Å, β = 96.04(2)°, V = 2015.9Å3, Z = 4, Rgt(F) = 0.039, wRref(F2) = 0.106, T = 125 K.

Published
2006

75. Characterization of phytoplankton assemblages in a tropical coastal environment using Kohonen self-organizing map.

Author

Osemwegie, Isimemen, Niamien‐Ebrottié, Julie E., Koné, Mathieu Y. J., Ouattara, Allassane, Biemi, Jean, and Reichert, Barbara

Subjects
ABIOTIC environment, PHYTOPLANKTON, SELF-organizing maps, DIATOMS, CYANOBACTERIA
Abstract

Copyright of African Journal of Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Published
2017
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76. Access to C-protected β-amino-aldehydes via transacetalization of 6-alcoxy tetrahydrooxazinones and use for pseudo-peptide synthesis

Author

Robert Dhal, Pavlo Shpak-Kraievskyi, Biaolin Yin, Mathieu Y. Laurent, Arnaud Martel, Gilles Dujardin, Unité de chimie organique moléculaire et macromoléculaire (UCO2M), and Le Mans Université (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)

Subjects
medicine.drug_class, Stereochemistry, peptide aldehyde, Peptide, Carboxamide, 010402 general chemistry, 01 natural sciences, Biochemistry, Aldehyde, Chemical synthesis, Maraviroc, chemistry.chemical_compound, β-amino acetal, Drug Discovery, Peptide synthesis, medicine, Enantiomeric excess, Peptide coupling, ComputingMilieux_MISCELLANEOUS, chemistry.chemical_classification, 010405 organic chemistry, [CHIM.ORGA]Chemical Sciences/Organic chemistry, Organic Chemistry, Acetal, 0104 chemical sciences, chemistry, Transacetalization, Amine gas treating
Abstract

Efficient access to masked β-amino-aldehydes was performed starting from 6-alcoxy tetrahydrooxazinone 6a–d (6-ATO). Transacetalization leads to the opening of the cycle to form either unsymmetric acetal 7 or symmetric acetals 16–18. These amino acetals are key compounds, obtained with 99% ee, which can be engaged in efficient peptide coupling. This method could easily provide peptides aldehydes or small amido aldehydes as exemplified with the formal synthesis of ent-Maraviroc.

Published
2012

80. ChemInform Abstract: A Practical Synthesis of para Di- and Mono-Substituted Benzhydrylamines from Benzhydrol Precursors

Author

Jacqueline Marchand-Brynaert and Mathieu Y. Laurent

Subjects
Chiral column chromatography, Carbamate, Chemistry, medicine.medical_treatment, medicine, Basic hydrolysis, General Medicine, Medicinal chemistry, Diphenylmethane derivatives
Abstract

A series of para-substituted benzhydrylamines 6 were obtained by substitution of the corresponding benzhydrol precursors 1 with phenyl carbamate 2 under acidic conditions, followed by basic hydrolysis of the carbamate intermediates 3. One unsymmetrical intermediate 3i has been resolved by preparative chiral chromatography. Subsequent deprotection of the carbamate function led to the recovery of enantiomerically pure (+)- and (-)-4-chlorobenzhydryl amines.

Published
2010

81. ChemInform Abstract: Access to α-Substituted Amino Acid Derivatives via 1,3-Dipolar Cycloaddition of α-Amino Ester Derived Nitrones

Author

Alice Beauseigneur, Gilles Dujardin, Arnaud Martel, Robert Dhal, Mathieu Y. Laurent, and Thanh Binh Nguyen

Subjects
chemistry.chemical_classification, chemistry, 1,3-Dipolar cycloaddition, Substituted Amino Acid, Organic chemistry, General Medicine, Cycloaddition, Alkyl, Amino acid, Stereocenter, Adduct
Abstract

Amino acid derived nitrones were conveniently synthesized in good-to-excellent yields by condensation of α-ketoesters with N-benzylhydroxylamine. The cycloaddition reactions of these nitrones with different alkenes were investigated under thermal solvent-free conditions. Considering conversions, yields, and selectivities, alkyl vinyl ethers have proven to be valuable partners to achieve this transformation, which creates a tetrafunctionalized stereogenic quaternary center. From the adducts derived from vinyl ethers, a three-step access to highly functionalized α-substituted amino acid derivatives is described.

Published
2010

84. Access to alpha-Substituted Amino Acid Derivatives via 1,3-Dipolar Cycloaddition of alpha-Amino Ester Derived Nitrones

Author

Gilles Dujardin, Alice Beauseigneur, Robert Dhal, Arnaud Martel, Thanh Binh Nguyen, Mathieu Y. Laurent, Unité de chimie organique moléculaire et macromoléculaire (UCO2M), and Le Mans Université (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)

Subjects
Magnetic Resonance Spectroscopy, Vinyl Compounds, Alkenes, 010402 general chemistry, 01 natural sciences, Stereocenter, Nitrone, Structure-Activity Relationship, medicine, Organic chemistry, Amino Acids, ComputingMilieux_MISCELLANEOUS, chemistry.chemical_classification, Molecular Structure, 010405 organic chemistry, Chemistry, Alkene, [CHIM.ORGA]Chemical Sciences/Organic chemistry, Organic Chemistry, Esters, Stereoisomerism, Vinyl ether, Condensation reaction, Cycloaddition, 0104 chemical sciences, Amino acid, Organic Chemistry Phenomena, Cyclization, 1,3-Dipolar cycloaddition, Nitrogen Oxides, medicine.drug
Abstract

Amino acid derived nitrones were conveniently synthesized in good-to-excellent yields by condensation of alpha-ketoesters with N-benzylhydroxylamine. The cycloaddition reactions of these nitrones with different alkenes were investigated under thermal solvent-free conditions. Considering conversions, yields, and selectivities, alkyl vinyl ethers have proven to be valuable partners to achieve this transformation, which creates a tetrafunctionalized stereogenic quaternary center. From the adducts derived from vinyl ethers, a three-step access to highly functionalized alpha-substituted amino acid derivatives is described.

Published
2010

87. Alimentation du Clupeidae Pellonula leonensis dans le lac de barrage de Buyo (Côte d’Ivoire)

Author

Kouamé, Martin K., Ouattara, Allassane, Dietoa, Mathieu Y., and Gourène, Germain

Subjects
Clupeidae, Diet, Ivory Coast, Lake of Buyo, Pellonula leonensis, West Africa
Abstract

Le régime alimentaire du Clupeidae Pellonula leonensis (Günther, 1868) a été étudié dans le lac de barrage hydroélectrique de Buyo, sur le fleuve Sassandra. L’échantillonnage a porté sur 430 spécimens, récoltés aux filets maillants au cours d’une campagne de pêche dans le lac, en période d’abondance de l’espèce dans les captures (août 2003). En dehors de l’aspect général de l’alimentation, l’analyse du régime a également été faite en fonction de la taille et du sexe des individus. L’indice d’importance relative (IRI) qui prend en compte les pourcentages d’occurrence, numérique et pondérale des différentes proies a été utilisé. Le régime alimentaire de P. leonensis est majoritairement constitué d’insectes, surtout de larves de Chironomidae (63,1% de l’IRI) mais aussi de crustacés, d’arachnides et de fruits. La mise en évidence statistique de l’effet de similitude de régime au moyen du coefficient de corrélation de Spearman montre que les individus des deux sexes exploitent les proies dans les mêmes proportions (rs = 0,50 ; p < 0,05). En revanche, les proportions des différents aliments varient en fonction de la taille des spécimens (rs = 0,42 ; p = 0,05).

Published
2006
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88. CMOS structures suitable for secured hardware

Author

Guilley, S., Hoogvorst, P., Mathieu, Y., Pacalet, Renaud, Provost, J., GET-Télécom Paris, Laboratoire Traitement et Communication de l'Information (LTCI), and Télécom ParisTech-Institut Mines-Télécom [Paris] (IMT)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[INFO.INFO-AR]Computer Science [cs]/Hardware Architecture [cs.AR], [INFO.INFO-CR]Computer Science [cs]/Cryptography and Security [cs.CR], Hardware_INTEGRATEDCIRCUITS, [INFO.INFO-ES]Computer Science [cs]/Embedded Systems, Hardware_PERFORMANCEANDRELIABILITY, Data_CODINGANDINFORMATIONTHEORY, [INFO.INFO-MO]Computer Science [cs]/Modeling and Simulation, Hardware_LOGICDESIGN, [SPI.TRON]Engineering Sciences [physics]/Electronics
Abstract

International audience; Unsecured electronic circuits leak physical syndromes correlated to the data they handle. Side-channels attacks, like SPA or DPA, exploit this information leakage. We provide balanced and memoryless CMOS structures for a 2-input secured NAND gate.

Published
2004

94. A New Method of N-Benzhydryl Deprotection in 2-Azetidinone Series

Author

Marcel Cérésiat, Marc Belmans, Jacqueline Marchand-Brynaert, Mathieu Y. Laurent, and Luc Kemps

Subjects
Hydrolysis, 2-Azetidinone, chemistry.chemical_compound, Bromine, chemistry, Polymer chemistry, Benzophenone, chemistry.chemical_element, General Medicine, Irradiation, Protecting group, Stoichiometry, Catalysis
Abstract

A mild and efficient procedure for the selective cleavage of N-benzhydryl protecting group of beta-lactams is described. The protected 2-azetidinones 4, precursors of carbapenems, were treated with a stoichiometric amount of N-bromosuccinimide and a catalytic amount of bromine under sun light irradiation in CH2Cl2-H2O mixture at 20 degreesC for 3 hours. The N-benzhydrol intermediates 6, which could be isolated, were then hydrolyzed with p-TsOH in aqueous acetone to furnish beta-lactams 7 and benzophenone quantitatively.

Published
2003

95. Mott versus Slater-type metal-insulator transition in Mn-substituted Sr3Ru2O7

Author

M. A. Hossain, B. Bohnenbuck, Y. D. Chuang, M. W. Haverkort, I. S. Elfimov, A.Tanaka, A. G. Cruz Gonzalez, Z. Hu, H.-J. Lin, C. T. Chen, R. Mathieu, Y. Tokura, Y. Yoshida, L. H. Tjeng, Z. Hussain, B. Keimer, G. A. Sawatzky and A. Damascelli and M. A. Hossain, B. Bohnenbuck, Y. D. Chuang, M. W. Haverkort, I. S. Elfimov, A.Tanaka, A. G. Cruz Gonzalez, Z. Hu, H.-J. Lin, C. T. Chen, R. Mathieu, Y. Tokura, Y. Yoshida, L. H. Tjeng, Z. Hussain, B. Keimer, G. A. Sawatzky and A. Damascelli

Published
2012
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96. P.1 - Calpainopathy in Chile, first cases reported

Author

Bevilacqua, J., Mathieu, Y., Krahn, M., Bartoli, M., Castiglioni, C., Kleinsteuber, K., Díaz, J., Puppo, F., Cerino, M., Courrier, S., Gorokhova, S., Miranda, N., Trangulao, A., González-Hormazábal, P., Avaria, M., Urtizberea, J., Caviedes, P., Jara, L., and Levy, N.

Published
2016
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98. Change in peroxidase activity during in vitro rooting of oil palm (Elaeis guineensis Jacq.)

Author

Rival, Alain, Bernard, Florence, and Mathieu, Y.

Subjects
CULTURE IN VITRO, ACTIVITE ENZYMATIQUE, ENRACINEMENT, PEROXYDASE, AUXINE
Abstract

Le comportement lors de l'enracinement in vitro de pousses feuillées de palmier à huile (#Elaeis guineensis$ Jacq.) issues de micropropagation clonale par embryogenèse somatique peut varier considérablement. Au cours de cette étude préliminaire, nous avons évalué l'activité gaïacol-péroxydase comme marqueur de l'enracinement in vitro. Nous avons étudié 17 clones différents, issus d'un protocole de micropropagation à grande échelle. Aucun phénomène d'enracinement n'a pu être observé en l'absence d'auxine exogène. L'activité péroxydasique présente l'évolution classiquement décrite chez d'autres espèces, présentant un pic entre 10 et 14 jours dans les meilleures conditions d'induction. Nous avons pu montrer que ce pic d'activité présente des décalages dans le temps, lorsque les taux d'enracinement mesurés sont faibles. L'activité péroxydasique avant induction par l'auxine a été mesurée sur 24 lots de production issus de 13 clones différents. Cette activité montre une hétérogénéité significativement plus forte dans les lots présentant un faible taux d'enracinement (< 50%). Différentes modifications du protocole d'enracinement sont proposées, dans le but d'en améliorer les performances en conditions de production à grande échelle. (Résumé d'auteur)

Published
1997

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