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Advances in Biological Chemistry 2024年第1期14卷 27-39页

作者： Donald Léonel Feugap Tsamo Cyrille Ngoufack Tagousop Arnaud Joseph Nguetse Dongmo Laurence Voutquenne-Nazabadioko David Ngnokam Research Unit of Applied and Environmental Chemistry Department of Chemistry Faculty of Science University of Dschang Dschang Cameroon department of Organic Chemistry Faculty of Science University of Yaoundé I Yaoundé Cameroon department of Basic Scientific Studies University Institute of Technology University of Ngaoundéré Ngaoundéré Cameroon Groupe Isolement et Structure Institut de Chimie Moléculaire de Reims (ICMR) Reims France

Starting from sissotrin (1), a natural isoflavonoid isolated from Trifolium baccarinii (Fabaceae), one new semisynthetic derivative, 6-nitrobiochanin A (1b) and two known derivatives, 8-nitrobiochanin A (1a) and 2",3",4",6"-tetraacetylsissotrin (1c) have been obtained after performing nitration and acetylation reactions. Their structures were assigned after interpretation of their spectrometric (HR-ESI-MS) and spectroscopic (NMR 1D and 2D) data and by comparison with those reported in the literature. The substrate as well as the semisynthetic derivatives were evaluated for their antibacterial activities against six strains. The results reveal that they are inactive or weakly active on the strains tested with the exception of 8-nitrobiochanin A (1a) which showed moderate activity (MIC = 62.5 μg∙mL−1) on Staphylococcus aureus ATCC 43300.

关键词： Trifolium baccarinii Isoflavonoid Nitration Acetylation Antibacterial Activity

Multifunctional properties of a polar spin chain compound[N(C_(3)H_(7))_(4)][Cu(C_(8)H_(4)NO_(4))]·H_(2)O exhibiting both one-dimensional magnetism and nonlinear optical activity

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Chinese Chemical Letters 2024年第2期35卷 622-625页

作者： Ang Li Yanhong Wang Haotian Tian Alimujiang Yalikun Yves Journaux Min Luo Hongcheng Lu Key Laboratory of Material Chemistry for Energy Conversion and Storage School of Chemistry and Chemical EngineeringHubei Key Laboratory of Bioinorganic Chemistry & Materia MedicaHuazhong University of Science and TechnologyWuhan 430074China Key Laboratory of optoelectronic Materials Chemistry and Physics Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 35002China institut Parisien de chimie Moléculaire IPCMSorbonne UniversitéCNRSParis F-75252France

Functional materials with multiple properties are urgent to be explored to reach high requirements for applications *** this work,a new multifunctional one-dimensional(1D)chain compound[N(C_(3)H_(7))_(4)][Cu(ohpma)]·H_(2)O 1(ohpma=deprotonated N-(2-hydoxyphenyl)oxamic acid)exhibiting both 1D antiferromagnetic and nonlinear optical properties,which are both originated from the same polar[Cu(C_(8)H_(4)NO_(4))]magnetic units,has been successfully synthesized by evaporation at room ***-polydentate nature of the(ohpma)3−ligand with constrained tridentate and bidentate coordination sites conducts Cu^(2+)ions coordinating in different geometries and forms 1D chains along the c axis,which are further separated by the[N(C_(3)H_(7))_(4)]+*** the 1D magnetic chains further exhibit noncentrosymmetric polar *** optical study shows polar compound 1 exhibits a discernible second-harmonic generation(SHG)efficiency and the calculation of the partial density of states indicates that the SHG efficiency of 1 is mainly originated from the polar[Cu(C_(8)H_(4)NO_(4))]magnetic ***,magnetic susceptibility shows a broad maximum around 70 K with strong intrachain interaction of J/k B=−113.0 K but no long-range order is observed down to 2 K,suggesting that 1 shows a good 1D *** good 1D magnetism and SHG activity suggest that 1 could be as a potential multifunctional material,particularly.

关键词： Multifunctional properties Magnetic property Nonlinear optical property Evaporation One-dimensional chain

Optimised NSAIDs-loaded Biocompatible Nanoparticles

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Nano-Micro Letters 2010年第4期2卷 247-255页

作者： V.Gaelle ROULLIN Maaite CALLEWAERT Michael MOLINARI Franck deLAVOIE Aurelie SECONde Marie-Christine ANDRY institut de chimie mole culaire de reims CNRS UMR 6229UFR Pharmacie Reims Laboratoire de Microscopies et d’Etudes des Nanostructures UFR des SciencesUniversitéde Reims Champagne-Ardenne Laboratoire de Microscopie Electronique Analytique INSERM UMRS 92621 rue Clement Ader51685 Reims Cedex 2France

In this formulation study,biocompatible non steroidal anti-inflammatory(NSAIDs)-loaded nanoparticles were designed as models to be further integrated in a prosthesis surface functionalization.A modified spontaneous emulsion-solvent diffusion methodology was used to produce drug-loaded PLGA nanoparticles without any purification or solvent evaporation *** parameters,such as lactide/glycolide ratio,polymer concentration,solvent/non solvent ratio and non solvent phase,as well as the non ionic tensioactive P188 co-precipitation composition were systematically *** optimized formulation(mean size:145 nm,surface charge:-13 m V) was employed to encapsulate various amounts of NSAIDs in a simple and scalable *** drug release was characterized in vitro by a complete release for 48 *** results encourage upcoming preliminary steps for in vivo experiments of prosthesis surface functionalization.

关键词： Drug delivery systems(DDS) Biocompatible Emulsion-solvent diffusion method PLGA Glycofurol Non steroidal anti-inflammatory drugs(NSAIDs)

Jasmonic Acid Oxidase 2 Hydroxylates Jasmonic Acid and Represses Basal defense and Resistance Responses against Botrytis cinerea Infection

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molecular Plant 2017年第9期10卷 1159-1173页

作者： Ekaterina Smirnova institut de Biologie Moléculaire des Plantes CNRS Université de Strasbourg Strasbourg France Laboratoire de chimie Organique Synthétique Institut de Chimie Université de Strasbourg CNRS Strasbourg France

Jasmonates （JAs） orchestrate immune responses upon wound/herbivore injury or infection by necrotro- phic pathogens. Elucidation of catabolic routes has revealed new complexity in jasmonate metabolism. Two integrated pathways attenuate signaling by turning over the active hormone jasmonoyl-isoleucine （JA-Ile） through w-oxidation or deconjugation, and define an indirect route forming the derivative 12OH-JA. Here, we provide evidence for a second 12OH-JA formation pathway by direct jasmonic acid （JA） oxidation. Three jasmonic acid oxidases （JAOs） of the 2-oxoglutarate dioxygenase family catalyze spe- cific oxidation of JA to 12OH-JA, and their genes are induced by wounding or infection by the fungus Botrytis cinerea. JA02 exhibits the highest basal expression, and its deficiency in jao2 mutants strongly enhanced antifungal resistance. The resistance phenotype resulted from constitutive expression of antimi- crobial markers rather than from their higher induction in infected jao2 plants and could be reversed by ectopic expression of any of the three JAOs injao2. Elevated defense injao2 was dependent on the activity of JASMONATE RESPONSE 1 （JAR1） and CORONATINE-INSENSITIVE 1 （COI1） but was not correlated with erihanced JA-Ile accumulation. Instead, jao2 mutant lines displayed altered accumulation of several JA species in healthy and challenged plants, suggesting elevated metabolic flux through JA-Ile. Collectively, these data identify the missing enzymes hydroxylating JA and uncover an important metabolic diversion mechanism for repressing basal JA defense responses.

关键词： 2-oxoglutarate oxygenase jasmonic acid defense regulation hormone metabolism Botrytis

Trifluoromethyl radical triggered radical cyclization of N-benzoyl ynamides leading to isoindolinones

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Science China Chemistry 2019年第11期62卷 1542-1546页

作者： Maud Cassé Christian Nisole Héloise Dossmann Yves Gimbert Jean-Marie Fourquez Laure Haberkorn Cyril Ollivier Louis Fensterbank Sorbonne Université CNRSInstitut Parisien de Chimie MoléculaireIPCM75005 ParisFrance institut de Recherches Servier 78290 Croissy-sur-SeineFrance Département de chimie Moléculaire CNRSUniversitéGrenoble Alpes38610 GièresFrance

Under photocatalytic reductive conditions,trifluoromethyl radical addition onto an ynamide followed by cyclization on a benzoyl moiety produces diverse isoindolinone platforms with good *** selectivity of the radical cyclization,N-benzoyl vs.N-benzyl as radical acceptor and the E/Z ratio of isomers have been rationalized by modeling.

关键词： ynamides trifluoromethylation photocatalysis cascade reactions tandem processes isoindolinones modeling

Recent advances on application of polysaccharides in cosmetics

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Journal of dermatologic science and cosmetic technology

Journal of dermatologic science and cosmetic technology 2024年第1期1卷 21-36页

作者： Qingyuan Wu Na Cheng Danjiao Fang Hao Wang Faiz-Ur Rahman Huifang Hao Yongmin Zhang Inner Mongolia University Research Center for Glycochemistry of Characteristic Medicinal Resources School of Chemistry and Chemical EngineeringInner Mongolia UniversityHohhot 010021China Sorbonne Université CNRSInstitut Parisien de Chimie MoléculaireUMR 82324 Place Jussieu75005 ParisFrance Key Laboratory of Tropical Medicinal Resource Chemistry of Ministry of Education College of Chemistry and Chemical EngineeringHainan Normal UniversityHaikou 571158China

Natural products have attracted wide attention in the cosmetics market due to their safety and high *** a highly active substance in nature,natural polysaccharides have been reported in recent years to have various cosmetic activities such as moisturizing,whitening,anti-aging and repairing skin,and are becoming a hot research topic in the cosmetics *** present,the mechanism of polysaccharide exerting cosmetic activity has been widely studied,but the relationship between polysaccharide’s chemical structure and cosmetic activity has not been effectively analyzed,which leads to the limitation of polysaccharide *** this review,the mechanism of polysaccharides exerting cosmetic activities such as moisturizing,whitening,anti-aging and skin repair was *** potential relationship between the structure and activity of polysaccharides was summarized by analyzing the influence of physical and chemical properties of polysaccharides,such as extraction method,molecular weight,monosaccharide composition,functional group and structural modification,etc.,which laid a foundation for the analysis of the structure-activity relationship of polysaccharides and improved its cosmetic value.

关键词： Polysaccharide Cosmetics Physical and chemical properties Structure-activity relationship Biological activity

Epitaxial Growth of Gd_(0.67)Ca_(0.33)MnO_3 Thin Films by Laser Ablation

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Journal of Rare Earths 2004年第6期22卷 739-742页

作者：马衍伟 Guilloux Viry M Barahona P Pea O Moure C Applied Superconductivity Laboratory Institute of Electrical Engineering Chinese Academy of Sciences Beijing 100080 China Chimie du Solide et Inorganique Moléculaire UMR 6511 CNRS - Université de Rennes 1 Institut de Chimie de Rennes 35042 Rennes France chimie du Solide et Inorganique Moléculaire UMR 6511 CNRS - Université de Rennes 1 Institut de Chimie de Rennes 35042 Rennes France instituto de Ceramica y Vidrio CSIC Campus de Cantoblanco 28049 Madrid Spain

Gd_(0.67)Ca_(0.33)MnO_3(GCMO)thin films grown by laser ablation on SrTiO_3(100)(STO)substrates was studied. Films are highly crystallized, very well epitaxial and single-phased. The ordering magnetic temperature(T_c)of the films is much higher than the value of bulk samples of similar composition. It is found that the GCMO film exhibits a reversal of its magnetization at low temperature when cooled under a magnetic field. The negative magnetization is a consequence of the rapid increase(～1/T)with decreasing temperature of the magnetization of a sublattice aligned antiparallel to the local field, relative to the magnetic contribution of a second sublattice which is aligned parallel to the applied field.

关键词： pulsed laser deposition Gd_(0.67)Ca_(0.33)MnO_3 thin films magnetic properties

Synthesis of 3″-and 4″-deoxy-Lewis^x trisaccharides:A useful tool for study of carbohydrate-carbohydrate interaction

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Science China Chemistry 2010年第9期53卷 1963-1969页

作者： GOURMALA Chafika Université Pierre et Marie Curie-Paris 6 Institut Parisien de Chimie Moléculaire

Synthesis of 3″-deoxy and 4″-deoxy Lewisx trisaccharides is *** 2,3,6-tri-O-benzoyl-4-deoxy-1-thio-β-Dxylo-hexopyranoside was condensed with a diol of glucosamine to give regio-and stereo-selectively a ***-lective fucosylation of this disaccharide provided a protected deoxy Lewisx trisaccharide which was deprotected to give the 4″-deoxy Lewisx *** of the similar synthetic sequence provided the 3″-deoxy Lewisx trisaccharide.

关键词： carbohydrate glycosylation synthesis trisaccharide.

Synthesis of P,N-2,2'-biphenyl derivatives with central chirality

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Science China Chemistry 2010年第9期53卷 1907-1913页

作者： JEAN Ludovic POULIQUEN Michael BLANCHET Jérme LASNE Marie-Claire ROUdeN Jacques Laboratoire de chimie Moléculaire et Thioorganique UMR 6507 CNRS-ENSICAEN & Université de Caen-Basse Normandie6 Boulevard du Maréchal Juin14050 CaenInstitut Normand de Chimie MoléculaireMédicinale et Macromoléculaire(INC3M)

Enantiopure 2-(dicyclohexylphosphino)-1,1'-biphenyl derivatives substituted in the 2'-position by a chiral amino group were *** the compound bearing an acyclic chiral chain,the key step was a Suzuki coupling between bromobenzeneboronic acid and N-Boc-iodoaniline whereas an aromatic nucleophilic substitution allowed the introduction of a chiral pyrrolidine in the 2'-position of the biphenyl *** efficiency of the P,N-biphenyl pyrrolidine derivatives as ligands in Pd-catalyzed arylaminations compares well with that of DavePhos ligand.

关键词： 3-aminopyrrolidines Suzuki coupling biphenyls chiral ligand arylamination

Dialkyl imidazolium acetate ionosilica as efficient and recyclable organocatalyst for cyanosilylation reactions of ketones

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Green Energy & Environment 2020年第2期5卷 130-137页

作者： Thanh Tran Duy Alysson Duarte Rodrigues Giang Vo-Thanh Peter Hesemann institut de chimie Moléculaire et des Matériaux D'Orsay UniversitéParis-SaclayUMR 818291405 Orsay CedexFrance institut Charles Gerhardt de Montpellier Universitéde MontpellierUMR 5253 CNRS-UM-ENSCMPlace E.Bataillon34000 MontpellierFrance

We report new heterogeneous organocatalyst based on silica hybrid supported N-heterocyclic carbene(NHC-)*** organocatalyst is formed from an imidazolium iodide based ionosilica material,followed by iodide/acetate anion *** imidazolium acetate generates the organocatalytic carbene via partial deprotonation of the imidazolium ring in *** monitored via EDX,solid state NMR and ion chromatography measurements,the iodide/acetate exchange involving the imidazolium ionosilica material took place only in small *** the fact that the exchanged material contains only a very small amount of acetate,we observed good catalytic activity and recyclability in cyanosilylation reactions of ketones with trimethylsilyl *** versatility of the catalyst was highlighted via reaction with several substrates,yielding the corresponding cyanohydrins in good *** recycling experiments,the material showed decreasing catalytic activity starting from the third reaction cycle,but high catalytic activity can be regenerated via another acetate *** work is important as it highlights the possibility to combine carbene chemistry and silica,which are antagonistic at a first *** show that imidazolium acetate based ionosilicas are therefore heterogeneous'proto-carbenes',and that there is no need to form strongly basic silica supported NHCs to obtain heterogeneous *** work therefore opens the route towards heterogeneous and re-usable NHC-organocatalysts from supported ionic liquid imidazolium acetates.

关键词： N-heterocyclic carbenes Ionosilica Heterogeneous organocatalysis Cyanosilylation Ionic liquids