255 research outputs found

    New Visible Light-triggered Photocatalytic Trifluoromethylation Reactions of Carbon‐carbon Multiple Bonds and (Hetero)aromatic Compounds

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    Visible-light-photocatalyzed methods employed insynthetic transformations present attractive properties such asenvironmentally friendly, safety, availability and excellent functionalgroup tolerance. In this venue, research on the visible-lightphotocatalytic incorporation of the trifluoromethyl CF3 moiety intoorganic substrates, in particular, has contributed to a clear evolutionof the very field of photocatalysis. Outer-sphere electron transfersbetween photocatalysts and trifluoromethyl sources supply CF3radicals efficiently in clean and controlled ways, capable of effectingnumerous synthetic transformations and functionalization on organicsubstrates and compounds with pharmacological activity instraightforward manners. Although this particular area is constantlyevolving and reviewed, the last five years have experienced anoutburst of seminal and significant photocatalytic trifluoromethylationexamples that are leading the way and opening new syntheticavenues. Recent review articles on Ru- and Ir- based photocatalytictrifluoromethylation reactions have borne witness of this evolution.Although this account will show the new Ru- and Ir-basedphotocatalytic trifluoromethylations, Sections 2 and 3 will alsoillustrate other photocatalytic systems, such as organic dyes, organicsemiconductors and newly-developed all-organic photocatalysts. All the known and reviewed strategies for photocatalytictrifluoromethylation reactions of olefins and (hetero)aromaticcompounds will not be discussed but will be summarized in twoFigures (Figures 4 and 5), and new examples (2015-present) will bepresented and discussed.Fil: Barata Vallejo, Sebastian. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Orgánica; ArgentinaFil: Postigo, Jose Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Orgánica; Argentin

    Intramolecular Pd(II)-Catalyzed Cyclization of Propargylamides: Straightforward Synthesis of 5-Oxazole-carbaldehydes

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    (Chemical Equation Presented) Direct synthesis of 2-substituted 5-oxazolecarbaldehydes was performed by intramolecular reaction of propargylamides through treatment with a catalytic amount of Pd(II) salts in the presence of a stoichiometric amount of reoxidant agent. The heterocyclization process was well-tolerated by a wide range of aryl, heteroaryl, and alkyl propargylamides. This protocol constitutes a valuable synthetic pathway to 5-oxazolecarbaldehydes, alternative to the formylation on oxazole rings, often unsatisfactory in term of regioselectivity and yields

    Multicenter evaluation of use of dried blood spot compared to conventional plasma in measurements of globotriaosylsphingosine (LysoGb3) concentration in 104 Fabry patients.

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    Abstract Objectives Fabry disease (FD) is an X-linked lysosomal storage disorder, resulting from a deficiency of the enzyme α-galactosidase A, responsible for breaking down glycolipids such as globotriaosylceramide and its deacylated derivative, globotriaosylsphingosine (LysoGb3). Here, we compare the levels of LysoGb3 in dried blood spots (DBS) and plasma in patients with classic and late-onset phenotypes. Methods LysoGb3 measurements were performed in 104 FD patients, 39 males and 65 females. Venous blood was collected. A portion was spotted onto filter paper and another portion separated to obtain plasma. The LysoGb3 concentrations in DBS and plasma were determined by highly sensitive electrospray ionization liquid chromatography tandem mass spectrometry. Agreement between different matrices was assessed using linear regression and Bland Altman analysis. Results The method on DBS was validated by evaluating its precision, accuracy, matrix effect, recovery, and stability. The analytical performances were verified by comparison of a total of 104 paired DBS and plasma samples from as many FD patients (representing 46 GLA variants). There was a strong correlation between plasma and the corresponding DBS LysoGb3 concentrations, with few exceptions. Discrepancies were observed in anemic patients with typically low hematocrit levels compared to the normal range. Conclusions The method proved to be efficient for the rapid analysis of LysoGb3. DBS provides a convenient, sensitive, and reproducible method for measuring LysoGb3 levels for diagnosis, initial phenotypic assignment, and therapeutic monitoring in patients with FD

    Synergistic effect of graphene nanoplatelets and carbon black in multifunctional EPDM nanocomposites

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    NMP is supported by the European Research Council (ERC StG Ideas 2011 BIHSNAM n. 279985 on “Bio-Inspired hierarchical supernanomaterials”, ERC PoC 2013 KNOTOUGH n. 632277 on “Supertough knotted fibers”, ERC PoC 2015 SILKENE nr. 693670 on “Bionic silk with graphene or other nanomaterials spun by silkworms”), by the European Commission under the Graphene Flagship (WP10 “Nanocomposites”, n. 604391) and by the Provincia Autonoma di Trento (“Graphene Nanocomposites”, n. S116/2012-242637 and delib. reg. n. 2266). The authors thank MINECO for the partial financial support of this work (project MAT2013-48107-C3). Dr. Manoj Tripathi (Center for Materials and Microsystems, Fondazione Bruno Kessler, Trento – Italy) is gratefully acknowledged for Raman measurements

    Nervous system and Fabry disease, from symptoms to diagnosis: damage evaluation and follow-up in adult patients, enzyme replacement, and support therapy

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    The X-linked genetic Fabry disease causes multiorgan lesions due to intracellular storage of the substrate globotriaosylceramide. Neurological involvement ranges from painful, small fiber neuropathy to cerebrovascular disorders to multifocal aggressive forms. Disease identification through proper differential diagnosis and timely assessment of organ damage should guide a careful treatment planning. Mainstay treatment, include enzyme replacement and support therapy. Neurologists have a pivotal role in early instrumental and clinical detection of organ damage. A panel of experts has developed a set of consensus recommendations to guide the approach of neurologists to Fabry disease

    Artemisinin-Naphthoquine versus Artemether-Lumefantrine for Uncomplicated Malaria in Papua New Guinean Children: An Open-Label Randomized Trial

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    © 2014 Laman et al. Artemisinin combination therapies (ACTs) with broad efficacy are needed where multiple Plasmodium species are transmitted, especially in children, who bear the brunt of infection in endemic areas. In Papua New Guinea (PNG), artemether-lumefantrine is the first-line treatment for uncomplicated malaria, but it has limited efficacy against P. vivax. Artemisinin-naphthoquine should have greater activity in vivax malaria because the elimination of naphthoquine is slower than that of lumefantrine. In this study, the efficacy, tolerability, and safety of these ACTs were assessed in PNG children aged 0.5–5 y.An open-label, randomized, parallel-group trial of artemether-lumefantrine (six doses over 3 d) and artemisinin-naphthoquine (three daily doses) was conducted between 28 March 2011 and 22 April 2013. Parasitologic outcomes were assessed without knowledge of treatment allocation. Primary endpoints were the 42-d P. falciparum PCR-corrected adequate clinical and parasitologic response (ACPR) and the P. vivax PCR-uncorrected 42-d ACPR. Non-inferiority and superiority designs were used for falciparum and vivax malaria, respectively. Because the artemisinin-naphthoquine regimen involved three doses rather than the manufacturer-specified single dose, the first 188 children underwent detailed safety monitoring. Of 2,542 febrile children screened, 267 were randomized, and 186 with falciparum and 47 with vivax malaria completed the 42-d follow-up. Both ACTs were safe and well tolerated. P. falciparum ACPRs were 97.8% and 100.0% in artemether-lumefantrine and artemisinin-naphthoquine-treated patients, respectively (difference 2.2% [95% CI -3.0% to 8.4%] versus -5.0% non-inferiority margin, p?=?0.24), and P. vivax ACPRs were 30.0% and 100.0%, respectively (difference 70.0% [95% CI 40.9%–87.2%], p<0.001). Limitations included the exclusion of 11% of randomized patients with sub-threshold parasitemias on confirmatory microscopy and direct observation of only morning artemether-lumefantrine dosing.Artemisinin-naphthoquine is non-inferior to artemether-lumefantrine in PNG children with falciparum malaria but has greater efficacy against vivax malaria, findings with implications in similar geo-epidemiologic settings within and beyond Oceania.Australian New Zealand Clinical Trials Registry ACTRN12610000913077.Please see later in the article for the Editors' Summary
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