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61.
Malika Berredjem Houria Djebbar Zine Regainia Nour-Eddine Aouf Georges Dewynter Jean-Yves Winum 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4):693-705
The regiospecific synthesis of chiral N-acyl cyclosulfamides (sulfa-analogues of cyclic ureas) was carried out starting from chlorosulfonyl isocyanate (CSI), 1-substituted N-benzyl-2-chloroethylamine hydrochloride and acyl chloride. Chiral N-acyl-thiadiazolidines 1,1-dioxides have been prepared in high yield starting from the corresponding cyclosulfamides acyl chloride, triethylamine and a catalytic amount of 4-(N,N-dimethylamino)pyridine. L'accès régiospécifique aux cyclosulfamides chiraux N-acylés (analogues sulfonés d'urèes cycliques) a été développé à partir de l'isocyanate de chlorosulfonyle, de N-benzyl-2-chloroéthylamine chirale substituée en position 1 et de chlorure d'acide. Les N-acyl thiadiazolidines 1,1-dioxydes chirales ont été préparées avec des rendements élevés à partir du cyclosulfamide correspondant par traitement avec un chlorure d'acide en présence de triéthylamine et une quantité catalytique de 4-(N,N-dimethylamino)pyridine. 相似文献
62.
Malika Ibrahim-Ouali 《Tetrahedron letters》2010,51(28):3610-3676
The first total synthesis of 11-tellura steroids was achieved via an intramolecular Diels-Alder cycloaddition of o-quinodimethanes as the key step. 相似文献
63.
64.
Abdussalam Sughir Mohamed Skiba Pedro Lameiras Gaël Coadou Malika Lahiani-Skiba Hassan Oulyadi 《Journal of inclusion phenomena and macrocyclic chemistry》2010,68(1-2):55-63
Tiagabine (TGB) is an antiepileptic agent enhancing the activity of GABA at neuronal and glial region. It has recently been shown that enhancement of TGB chemical stability was improved by complexation with 2-hydroxypropyl-beta-cyclodextrin (2-HPβCD). The aim of this project is to explain the improvement of the chemical stability of complexed TGB by studying the inclusion properties and factors affecting the complexation selectivity between 2-HPβCD and TGB. Analysis of the interaction between 2-HPβCD and TGB and the effect of 2-HPβCD on TGB solubility was performed by phase solubility method described by Higuchi and Connors; the complexation was followed by characterization using DSC, FTIR and NMR spectroscopy. In aqueous media, the analysis of NMR proton shift change continuous variation method (Job’s plot) and the NMR diffusion-ordered spectroscopy (DOSY) measurements clearly show that TGB form 1:1 inclusion complex with 2-HPβCD with an association constant (K a) of 3396 M?1. More detailed information about the inclusion mode and the geometry of the complex was obtained by the analysis of 2D NMR NOESY experiment and molecular modelling calculations. The inclusion process indicates that A-ring, C10–C11 double bond and the half of the B-ring of TGB molecule were located inside the cavity while the nipecotic acid part of TGB (Ring C) was exposed towards the outside of the 2-HPβCD cavity. These results suggest that the inclusion of the C10–C11 double bond in the 2-HPβCD cavity may possibly the reason of improvement of TGB chemical stability. 相似文献
65.
Hospital A Gibard C Gaulier C Nauton L Théry V El-Ghozzi M Avignant D Cisnetti F Gautier A 《Dalton transactions (Cambridge, England : 2003)》2012,41(22):6803-6812
A new strategy was developed for the modification of silver(I) and gold(I) N-heterocyclic carbenes. Azido groups were grafted and used either by copper-catalysed azide-alkyne cycloaddition before metallation or by thermal and "strain-promoted" 1,3-dipolar cycloaddition after metallation to functionalise the metal-NHCs. 相似文献
66.
Lakhdar S Goumont R Boubaker T Mokhtari M Terrier F 《Organic & biomolecular chemistry》2006,4(10):1910-1919
A study of the dual electrophilic and pericyclic reactivity of 4,6-dinitrobenzofurazan (DNBZ, 2), 4,6-dinitro-2,1,3-benzothiadiazole (DNBS, 3), 4,6-dinitro-2,1,3-benzoselenadiazole (DNBSe, 4) is reported. Kinetic and thermodynamic measurements of the ease of covalent hydration of 2-4 to give the corresponding hydroxy sigma-adducts C-2-C-4 have been carried out over a large pH range in aqueous solution. Analysis of the data has allowed a determination of the rate constants k1(H2O) pertaining to the susceptibility of 2-4 to water attack as well as the pKa values for the sigma-complexation processes. With pKa values ranging from 3.92 for DNBZ to 6.34 for DNBSe to 7.86 for DNBS, the electrophilic character of the three heteroaromatics is much closer to that of the superelectrophilic reference, i.e. 4,6-dinitrobenzofuroxan (DNBF, 1; pKa = 3.75), than that of the standard Meisenheimer electrophile 1,3,5-trinitrobenzene (TNB, pKa = 13.43). Most importantly, water is found to be an efficient nucleophile which contributes strongly to the formation of the adducts C-2 and C-4. This confirms a previous observation that a pKa value of ca. 8 is a primary requirement for having H2O competing effectively as a nucleophile with OH- in the formation of hydroxy sigma-adducts. On the other hand, 2-4 are found to exhibit dienophilic and/or heterodienic behaviour on treatment with isoprene, 2,3-dimethylbutadiene, cyclopentadiene or cyclohexadiene, affording Diels-Alder mono- or di-adducts which have all been structurally characterized. A major finding is that the order of Diels-Alder reactivity follows clearly the order of electrophilicity, pointing to a direct relationship between superelectrophilic and pericyclic reactivity. This relationship is discussed. 相似文献
67.
Elisabeth Pereira Ali Youssef Malika El-Ghozzi Daniel Avignant Jennifer Bain Michelle Prudhomme Fabrice Anizon Pascale Moreau 《Tetrahedron letters》2014
Two dipyrrolo[3,4-a:3,4-c]carbazole stereoisomers were unexpectedly obtained by Diels–Alder dimerization of 3-indolylmaleimide. Three dimensional structures of both stereoisomers were confirmed by X-ray analysis. Moreover compound 4 inhibits protein kinases in vitro, especially Pim-3, in the sub-micromolar range. 相似文献
68.
Zouaoui Setifi Fatima Setifi Lahcen El Ammari Malika El‐Ghozzi Jana Sopkov‐de Oliveira Santos Hocine Merazig Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(1):19-22
In the title compound, [Cu(C9H5N4O)Cl(C12H8N2)]n or [Cu(tcnoet)Cl(phen)]n, where phen is 1,10‐phenanthroline and tcnoet is 1,1,3,3‐tetracyano‐2‐ethoxypropenide, the axially elongated (4 + 2) coordination polyhedron around the CuII centre contains N atoms from three different tcnoet ligands. The resulting coordination polymer takes the form of sheets which are linked in pairs by a single C—H...N hydrogen bond to form bilayers. The bond lengths provide evidence for significant bond fixation in the phen ligand and extensive electronic delocalization in the tcnoet ligand, where the two –C(CN)2 units are rotated, in conrotatory fashion, out of the plane of the central C3O fragment. 相似文献
69.
Ganapathy Balaji Mehran Samiee Esfahani Pranav Joshi Joydeep Bhattacharaya Malika Jeffries-EL Vikram Dalal 《European Polymer Journal》2013
We report the synthesis of two solution-processable reduced band gap donor–acceptor conjugated polymers p(C8-DPP-F) and p(C12-DPP-F), composed from 9,9-dioctylfluorene as the donor moiety, diketopyrrolopyrrole (DPP) moiety as the acceptor moiety and furan bridges. Two different alkyl chains, n-dodecyl and n-octyl were used on the DPP moiety and the impact of this structural modification evaluated in detail. Both polymers exhibited similar optical and electrochemical properties with optical band gap of around 1.75 eV as result of LUMO levels near −3.4 eV and high-lying HOMO levels of ∼5.2 eV. Bulk heterojunction photovoltaic devices using these polymers electron donors along with PC70BM as the electron acceptor, gave power conversion efficiency of 1.60% and 0.75% for p(C12-DPP-F) and p(C8-DPP-F) respectively. 相似文献
70.
Taher Boukhris Malika Lahiani-Skiba Damien Martin Mohamed Skiba 《Journal of inclusion phenomena and macrocyclic chemistry》2013,75(3-4):323-332
The purpose of this study was to develop a new oral cyclosporine A (CsA) formulation free of surfactant cremophor using cyclodextrin terpolymers (P-αβ-CD, P-βγ-CD and P-αγ-CD) as excipients in attempt to enhance its stability, dissolution rate and eliminate surfactant side effects. Two spray-dried dispersions (SDDs) containing poorly water-soluble CsA were prepared with either P-αβ-CD, P-βγ-CD or P-αγ-CD using water ( $ F_{{{\text{H}}_{2} {\text{O}}}} $ ) and ethanol (F EOH) via spray-drying technique and characterized by scanning electron microscopy, powder X-ray diffraction, particle size distribution, circular dichroism (CD) and nuclear magnetic resonance along with the dissolution study which was compared to Neoral® and Sandimmune®. The results showed an interaction between CsA and P-αβ-CD, P-βγ-CD and P-αγ-CD without secondary structure change of CsA. The order of the CsA release from the terpolymers was ranked as follows: P-αγ-CD/CsA ( $ F_{{{\text{H}}_{2} {\text{O}}}} $ ) = Neoral® > P-βγ-CD/CsA ( $ F_{{{\text{H}}_{2} {\text{O}}}} $ ) > P-αβ-CD/CsA ( $ F_{{{\text{H}}_{2} {\text{O}}}} $ ) > P-αγ-CD/CsA (F EOH) > Sandimmune® > P-αβ-CD/CsA (F EOH) > P-βγ-CD/CsA (F EOH). The results of ( $ F_{{{\text{H}}_{2} {\text{O}}}} $ ) could be explained by hydrophilisation and absence of crystallinity of CsA while maintaining part of its crystallinity in the case of formulations (F EOH). In summary, developed SDD formulations P-αγ-CD/CsA ( $ F_{{{\text{H}}_{2} {\text{O}}}} $ ) revealed same dissolution profile as Neoral® and better than Sandimmune®. These systems seem to be stable to carry cyclosporine and release it, while preserving structure and thus, potentially, also maintaining cyclosporine activity. 相似文献