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91.
92.
The two-dimensional cyano-bridged coordination polymer Er(H(2)O)(4)[W(CN)(8)] exhibits a magnetic transition at 12 K and an unusual field-dependent transition from short-range to ferromagnetic ordering. 相似文献
93.
94.
Yannick Borde Adrien Danel Agnes Roche Marc Veillerot 《Spectrochimica Acta Part B: Atomic Spectroscopy》2008
Among the methods available on the market today to control as metallic contamination in integrated circuit manufacturing, Sweeping Total reflection X-ray Fluorescence mode appears a very good method, providing fast and entire wafer mapping. With the goal of a pertinent use of Sweeping Total reflection X-ray Fluorescence in advanced Integrated Circuit manufacturing this work discusses how acceptable levels of contamination specified by the production (low levels to be detected) can be taken into account. 相似文献
95.
Cis-2,4- and cis-cis-2,4,5-substituted tetrahydrofurans have been prepared stereoselectively using electrophile-mediated cyclization of β-hydroxyhomoallylsilanes, readily available from α-silylacetic esters. 相似文献
96.
Bachir Douara Yannick J. Esvan Elisabeth Pereira Francis Giraud Yulia L. Volodina Dmitry N. Kaluzhny Alexander A. Shtil Fabrice Anizon Pascale Moreau 《Tetrahedron》2018,74(8):892-901
Pyrazole analogs of the staurosporine aglycon K252c were recently described as potent inhibitors of the three Pim protein kinase isoforms. To evaluate the impact of the introduction of a sugar moiety on the biological activities of this heterocyclic scaffold, four new glucosylated pyrazole analogs of K252c were synthesized. Their biological evaluation demonstrated that most active compounds 11 and 19 substituted by a β-d-glucosyl moiety at N12 or N13 positions exhibited antiproliferative activities toward HCT116 cells. 相似文献
97.
Nierengarten JF Zhang S Gégout A Urbani M Armaroli N Marconi G Rio Y 《The Journal of organic chemistry》2005,70(19):7550-7557
[structure: see text] Branched conjugated systems with a terminal alkyne function have been prepared starting from 4-(triisopropylsilylethynyl) phenylacetylene by applying the following iterative reaction sequence: (i) metal-catalyzed cross-coupling reaction of the terminal alkyne with 3,4-dibromobenzaldehyde or 2,5- dibromobenzaldehyde; (ii) Corey-Fuchs dibromoolefination and treatment with an excess of LDA. The building blocks thus prepared have been subjected to a Pd-catalyzed cross-coupling reaction with 1,4-diiodobenzene to yield isomeric branched pi-conjugated systems containing 7 (first generation) or 15 (second generation) phenyl units connected by ethynyl spacers. The different pi-conjugation patterns in those isomeric derivatives have a dramatic effect on their electronic properties, as attested by the differences observed in their absorption and emission spectra. Finally, theoretical calculations have been performed to rationalize the optical properties of these compounds. 相似文献
98.
Yannick Borguet 《Tetrahedron letters》2007,48(36):6334-6338
The first monomode microwave-assisted atom transfer radical additions (ATRA) of carbon tetrachloride to various olefins were successfully performed, affording the adducts with almost quantitative yields in less than 10 min at 160 °C. 相似文献
99.
Oxidative cleavage of C-Si bonds of polyhydroxylated silacyclopentanes under various conditions have led to both the desired polyols and to Peterson elimination products. Further studies on the reactivity of these silacycles, under acidic and basic conditions have been carried out, leading to unexpected results. Treatment of these silacycles under basic conditions thus provided various diols after the cleavage of Csp3-Si bonds. A mechanistic rationale has been proposed for each case. 相似文献
100.
Malika Lahiani-Skiba Yannick Boulet Ibrahima Youm Fréderic Bounoure Philippe Vérité Philippe Arnaud Mohamed Skiba 《Journal of inclusion phenomena and macrocyclic chemistry》2007,57(1-4):211-217
The aim of the study was to evaluate if the complexation of a hydrophilic molecule by cyclodextrins is possible. Cyclodextrins
(CDs) are hydrophilic cone shaped molecules, which are used as vehicles able to include organic molecules. Because of the
presence of hydroxy groups (OH) outside of the molecule, cyclodextrins are not predisposed to include hydrophilic drugs. They
are therefore used to improve the solubility of poor water-soluble molecules. In order to evaluate if the complexation of
a hydrophilic molecule by cyclodextrins is possible, lyophilized complexes of cysteamine hydrochloride with α-cyclodextrins
(α-CD) have been realized. Six analytical techniques (High performance Liquid Chromatography coupled to UV detection, Thin-Layer
Chromatography, Fourier Transform Infrared spectroscopy (FT-IR), Differential Scanning Calorimetry (DSC), Mass Spectrometry
(SM) and Proton Nuclear Magnetic Resonance (NMR-NOESY spectra)) were used in order to characterize the interaction between
the drug and the α-CD. The realization of complex between a cyclodextrin and a water-soluble drug seems feasible. In the case
of a hydrophilic molecule, the complexation is not obtained by inclusion of the drug in the cyclodextrin, but by binding to
the outside of the cone. This “external complexation” is however sufficient to improve some features of the molecule, such
as organoleptic features, and to modifiy measurable parameters (FT-IR, DSC, SM and NMR-NOESY spectra). 相似文献