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174.
Sebastien Blanquer Julien Tailhades Vincent Darcos Muriel Amblard Jean Martinez Benjamin Nottelet Jean Coudane 《Journal of polymer science. Part A, Polymer chemistry》2010,48(24):5891-5898
Novel 5‐Z‐amino‐δ‐valerolactone (5‐NHZ‐VL) was synthesized with an aim to prepare degradable polyesters and copolyesters having amino pendant groups. Following a straightforward and efficient synthetic pathway, 5‐NHZ‐VL was obtained in only two steps and up to 50% yield. The monomer was fully characterized by 1H NMR, 13C NMR, ESI mass spectrometry, and HPLC. Various conventional conditions were tested for this lactone ring‐opening polymerization and led to the novel corresponding poly(5‐NHZ‐VL) (Mn = 7000 g/mol; PD = 1.2). Following this homopolymerization, 5‐NHZ‐VL was copolymerized with ε‐caprolactone to generate a family of copolyesters with an amino‐group content ranging from 10 to 80%. Finally, the polyelectrolyte poly(5‐NH3+‐VL) was recovered by removal of the protecting group under acidic conditions, and integrity of the polyester backbone was confirmed by 1H NMR. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 相似文献
175.
We prove that the pre-Lie operad is a free non-symmetric operad. 相似文献
176.
Yvonnick LoidreauPascal Marchand Carole Dubouilh-BenardMarie-Renée Nourrisson Muriel DuflosThierry Besson 《Tetrahedron letters》2012,53(8):944-947
This Letter describes for the first time the synthesis of pyrido[2′,3′:4,5]furo[3,2-d]pyrimidines substituted by a primary or secondary amino group on position 4 of the pyrimidine ring. Application of microwave irradiation technology allowed fast and convenient procedures. 相似文献
177.
Isabelle Chaduc Wenjing Zhang Jutta Rieger Muriel Lansalot Franck D'Agosto Bernadette Charleux 《Macromolecular rapid communications》2011,32(16):1270-1276
The syntheses of amphiphilic block copolymers are successfully performed in water by chain extension of hydrophilic macromolecules with styrene at 80 °C. The employed strategy is a one‐pot procedure in which poly(acrylic acid), poly(methacrylic acid) or poly(methacrylic acid‐co‐poly(ethylene oxide) methyl ether methacrylate) macroRAFTs are first formed in water using 4‐cyano‐4‐thiothiopropylsulfanyl pentanoic acid (CTPPA) as a chain transfer agent. The resulting macroRAFTs are then directly used without further purification for the RAFT polymerization of styrene in water in the same reactor. This simple and straightforward strategy leads to a very good control of the resulting amphiphilic block copolymers.
178.
Jennifer Bourgeois Laure-Anne Pierson Julien Nicolas Muriel Lalanne Patrick Couvreur Karine Andrieux 《Journal of Thermal Analysis and Calorimetry》2009,98(1):65-71
Anti HIV molecules as numerous drugs cannot efficiently penetrate into the brain. Prodrug synthesis and encapsulation into
pegylated nanocarriers have been proposed as an approach for brain delivery. Pegylated polymeric nanoparticles and liposomes
were chosen to incorporate glycerolipidic prodrugs of didanosine. Differential scanning calorimetry experiments were performed
on mixtures of prodrugs and lipids or polymer in order to study their interaction. The optimal incorporation ratios were determined
for each prodrug and compared for both types of nanocarriers. All these results would be used to prepare optimised formulations
of didanosine prodrugs loaded into pegylated nanocarriers for brain drug delivery. 相似文献
179.
Santos JS Voisin-Chiret AS Burzicki G Sebaoun L Sebban M Lohier JF Legay R Oulyadi H Bureau R Rault S 《Journal of chemical information and modeling》2012,52(2):429-439
Protein-protein interactions are central to many biological processes, from intracellular communication to cytoskeleton assembly, and therefore represent an important class of targets for new therapeutics. The most common secondary structure in natural proteins is an α-helix. Small molecules seem to be attractive candidates for stabilizing or disrupting protein-protein interactions based on α-helices. In our study, we assessed the ability of oligopyridyl scaffolds to mimic the α-helical twist. The theoretical as well as experimental studies (X-ray diffraction and NMR) on conformations of bipyridines in the function of substituent and pyridine nitrogen positions were carried out. Furthermore, the experimental techniques showed that the conformations observed in bipyridines are maintained within a longer oligopyridyl scaffold (quaterpyridines). The alignment of the synthesized quaterpyridine with two methyl substituents showed that it is an α-helix foldamer; their methyl groups overlap very well with side chain positions, i and i + 3, of an ideal α-helix. 相似文献
180.
Sebastian Wagner Muriel Rakotomalala Yana Bykov Olaf Walter Manfred Dring 《Heteroatom Chemistry》2012,23(2):216-222
This article discusses the behavior of seven organophosphorus compounds under Atherton–Todd conditions. Therefore, the reactivity and selectivity of different (phen)oxaphosphinines, dioxaphosphinines, dioxaphosphinanes, and diphenylphosphine oxide with three nucleophiles were systematically studied. The results prove the versatility of the Atherton–Todd reaction to a broad range of organophosphorus compounds with different phosphorus environments and reactive P H bonds. The nucleophiles studied in this article were chosen as model substrates for amines and alcohols. Because organophosphorus molecules are important and versatile compounds, for a broad field of applications, novel synthetic approaches are of interest to both academia and industry. As an example, the single‐step synthesis of the bridged 1,3‐phenylene bis(diphenylphosphinate) with potential flame‐retardant properties was added to this study. In addition, the reaction is utilized for the synthesis of a novel organophosphorus anhydride. © 2012 Wiley Periodicals, Inc. Heteroatom Chem 23:216–222, 2012; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.21006 相似文献