Search results for "16."
showing 10 items of 7809 documents
Influence of the anions on the structure and magnetic properties of a series of bis(µ-diphexono)-bridged linear trinuclear copper(II) complexes: an e…
2011
The reaction of H(2)L (N,N'-dimethyl-N,N'-bis(2-hydroxy-3-methoxy-5-methylbenzyl)-ethylenediamine) with different copper salts, in methanol and using a H(2)L/Cu = 2 : 3 molar ratio, led to four new bis(μ-diphenoxo)-bridged Cu(3) complexes of general formula [{Cu(S)(μ-L)}(2)Cu(H(2)O)(2n)]X(2) (S = CH(3)OH, n = 1 and X = BF(4)(-) for (1) or ClO(4)(-) for (2); S = Br(3)(-) anion and n = 1 without any X species for (3); S = H(2)O, n = 0 and X = NO(3)(-) for (4)). The use in the same reaction conditions of 4,4'-bipyridine (4,4'-bipy) as connector led to the chain complex [{Cu(μ-4,4'-bipy)(0.5)(μ-L)}(2)Cu(H(2)O)(2n)](ClO(4))(2)·17H(2)O (5). The structure of the centrosymmetric trinuclear unit in …
Anion Recognition by a Bioactive Diureidodecalin Anionophore: Solid-State, Solution, and Computational Studies
2018
Recent work has identified a bis-(p-nitrophenyl)ureidodecalin anion carrier as a promising candidate for biomedical applications, showing good activity for chloride transport in cells yet almost no cytotoxicity. To underpin further development of this and related compounds, a detailed structural and binding investigation is reported. Crystal structures of the transporter as five solvates confirm the diaxial positioning of urea groups while revealing a degree of conformational flexibility. Structures of complexes with Cl−, Br−, NO3 −, SO4 2− and AcO−, supported by computational studies, show how the binding site can adapt to accommodate these anions. 1H NMR binding studies revealed exception…
Response to: 'IL-23 expression and activation of autophagy in synovium and PBMCs of HLA-B27 positive patients with ankylosing spondylitis' by Neerinc…
2014
We read with interest the study by Neerinckx et al 1 addressing the expression of interleukin (IL)-23p19 and of autophagy genes in the synovium and in the peripheral blood mononuclear cells of patients with ankylosing spondylitis (AS). Differently from our observation in the gut,2 the authors failed to demonstrate any significant increase by RT-PCR in the expression of synovium autophagy-related genes (ATG16L1, IRGM, MAP1LC3A, ATG5, HSPA8 and HSP90AA1) together with no significant overexpression of IL-23p19 compared with disease and healthy controls. We have previously demonstrated by immunohistochemistry that in the …
Macrophage Migration Inhibitory Factor Induces Inflammation and Predicts Spinal Progression in Ankylosing Spondylitis
2017
Objective: To investigate the role of macrophage migration inhibitory factor (MIF) in the pathogenesis of ankylosing spondylitis (AS). Methods: Patients who met the modified New York criteria for AS were recruited for the study. Healthy volunteers, rheumatoid arthritis patients, and osteoarthritis patients were included as controls. Based on the annual rate of increase in modified Stoke AS Spine Score (mSASSS), AS patients were classified as progressors or nonprogressors. MIF levels in serum and synovial fluid were quantitated by enzyme-linked immunosorbent assay. Predictors of AS progression were evaluated using logistic regression analysis. Immunohistochemical analysis of ileal tissue was…
N‐Heterocyclic Carbene Catalyzed [4+2] Annulation of Enals via a Double Vinylogous Michael Addition: Asymmetric Synthesis of 3,5‐Diaryl Cyclohexenones
2017
A strategy for the N-heterocyclic carbene (NHC) catalyzed asymmetric synthesis of 3,5-diaryl substituted cyclohexenones has been developed via oxidative [4+2] annulation of enals and alkenylisoxazoles. It is the first example of using NHC organocatalysis in a double vinylogous Michael type reaction, a challenging but highly desirable topic. This unprecedented protocol affords good yields as well as high to excellent diastereo- and enantioselectivities.
Switchable Access to Different Spirocyclopentane Oxindoles by N-Heterocyclic Carbene Catalyzed Reactions of Isatin-Derived Enals and N-Sulfonyl Ketim…
2017
A novel NHC-catalyzed annulation protocol for the asymmetric synthesis of biologically important β-lactam fused spirocyclopentane oxindoles with four contiguous stereocenters, including two quaternary carbon centers, was developed. Alternatively, spirocyclopentane oxindoles containing an enaminone moiety can be achieved using the same starting materials, isatin-derived enals, and N-sulfonyl ketimines, in the presence of a slightly different NHC catalytic system. This switchable annulation strategy enables the selective assembly of both heterocyclic scaffolds with good yields and excellent enantioselectivities for a broad range of substrates.
Asymmetric, Three-Component, One-Pot Synthesis of Spiropyrazolones and 2,5-Chromenediones from Aldol Condensation/NHC-Catalyzed Annulation Reactions
2016
A novel one-pot, three-component diastereo- and enantioselective synthesis of spiropyrazolones has been developed involving the aldol condensation of an enal to generate α,β-unsaturated pyrazolones, which react with a second equivalent of enal through an N-heterocyclic carbene (NHC)-catalyzed [3+2] annulation. The desired spirocyclopentane pyrazolones are obtained in moderate to good yields and good to excellent stereoselectivities. Alternatively, starting from cyclic 1,3-diketones, 2,5-chromenediones are available through [2+4] annulation.
Asymmetric Synthesis of Spiro-oxindole-ε-lactones through N-Heterocyclic Carbene Catalysis
2018
An unprecedented N-heterocyclic carbene-catalyzed annulation of isatin-derived enals and o-hydroxyphenyl-substituted p-quinone methides as bifunctional reagents has been discovered. The new protocol involves a 1,6-addition of the homoenolate equivalent intermediates to the hydroxy donor-1,6-Michael acceptors and leads to spirocyclic oxindole-ε-lactones in high yields and very good stereoselectivities.
IL CANTIERE DEL COMPLESSO CARMELITANO DELL’ANNUNZIATA A TRAPANI NELLA SECONDA METÀ DEL CINQUECENTO
2016
Il complesso carmelitano dell’Annunziata a Trapani, costituito dalla chiesa e dal convento annesso (oggi sede del Museo Regionale Agostino Pepoli), appare come un’architettura fortemente stratificata, frutto di una lunga e complessa vicenda progettuale che si snoda dal XIV secolo fino alla metà del Settecento. Il presente studio intende contribuire alla conoscenza del cantiere dell’Annunziata nella seconda metà del Cinquecento, un periodo ancora poco indagato dalle ricerche finora condotte sulla fabbrica, offrendo in particolare alcune riflessioni sui maestri impegnati nella costruzione del complesso architettonico, a partire dall’esame della documentazione relativa alla gestione amministra…
Images, carrières et modes de vie des enseignantes. Des années soixante à la décennie quatre-vingt-dix
1995
Between the two World Wars, women teachers were mosûy single ; since the 1970's, teachers who are married and bring up children have become the norm among high school teachers. In romantic fiction, one lays the stress on the distress of "lonely" women or on the conflicting roles of teachers who are also wives and mothers. Beyond these necessarily limiting images, this article aims at shedding light on the processes which come into play to determine different types of relationships with the teaching profession and career. Women's school ana university background, their husbands' career, the collective interests, play a role in the progress of professional life which in its turn influences th…