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21.
Hélio A. Stefani Claudio M.P. Pereira Roberta B. Almeida Karla P. Guzen 《Tetrahedron letters》2005,46(40):6833-6837
The 4-halo-3,5-dimethyl pyrazoles have been synthetisized in good yields in short reaction times in the absence of a catalyst by reaction of 3,5-dimethyl pyrazoles with N-halosuccinimides (NBS, NCS and NIS) under ultrasound irradiation. Finally, the halogenation of pyrazoles with Br2, ICl and I2 was showed in similar conditions. 相似文献
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2-and 4-Ethoxymethoxybenzyl methyl ethers were employied as useful starting materials for the synthesis of 1,2- or 1,4-dicarbo-substituted benzenes. The proposed reaction sequence involves connection between the reductive lithiation of benzyl alkyl ethers and the metal-catalyzed cross-coupling reaction of aromatic triflates. 相似文献
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Francielli S. Santana Mauro Perfetti Matteo Briganti Francesca Sacco Giordano Poneti Enrico Ravera Jaísa F. Soares Roberta Sessoli 《Chemical science》2022,13(20):5860
A common criterion for designing performant single molecule magnets and pseudocontact shift tags is a large magnetic anisotropy. In this article we present a dysprosium complex chemically designed to exhibit strong easy-axis type magnetic anisotropy that is preserved in dichloromethane solution at room temperature. Our detailed theoretical and experimental studies on the magnetic properties allowed explaining several features typical of highly performant SMMs. Moreover, the NMR characterization shows remarkably large chemical shifts, outperforming the current state-of-the art PCS tags.A robust dysprosium(iii) single molecule magnet with large uniaxial magnetic anisotropy induces pseudocontact shifts at almost doubled distance compared to standard shift agents. 相似文献
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Irene Dini Vittoria Alborino Stefania Lanzuise Nadia Lombardi Roberta Marra Anna Balestrieri Alberto Ritieni Sheridan L. Woo Francesco Vinale 《Molecules (Basel, Switzerland)》2022,27(12)
The contamination of agricultural products with mycotoxins causes risks to animal and human health and severe economic losses. Mycotoxicoses can be reduced by preventing fungal infection using chemical and biological approaches. The chemical strategies can release toxic molecules; therefore, strategies for biological control are being evaluated, such as using nontoxic fungi and their metabolites. This work evaluated the effect of exoenzymes produced by the beneficial fungus Trichoderma afroharzianum strain T22 in degrading Aflatoxin B1 (AFB1) and Ochratoxin A (OTA). The ability of Trichoderma to produce hydrolases was stimulated by using different inducing substrates. The highest AFB1 and OTA degradation activity was obtained using a medium containing lyophilized mushrooms and crude fiber. The T. afroharzianum T22’s ability to reduce mycotoxins may be attributed to peroxidase enzymes. This study showed that T. afroharzianum strain T22 or its peroxidase supplementation could represent a sustainable strategy for the degradation of AFB1 and OTA in feed and food products. 相似文献
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Valentina Noemi Madia Walter Toscanelli Daniela De Vita Marta De Angelis Antonella Messore Davide Ialongo Luigi Scipione Valeria Tudino Felicia Diodata DAuria Roberto Di Santo Stefania Garzoli Annarita Stringaro Marisa Colone Magda Marchetti Fabiana Superti Lucia Nencioni Roberta Costi 《Molecules (Basel, Switzerland)》2022,27(12)
Influenza viruses are transmitted from human to human via airborne droplets and can be transferred through contaminated environmental surfaces. Some works have demonstrated the efficacy of essential oils (EOs) as antimicrobial and antiviral agents, but most of them examined the liquid phases, which are generally toxic for oral applications. In our study, we describe the antiviral activity of Citrus bergamia, Melaleuca alternifolia, Illicium verum and Eucalyptus globulus vapor EOs against influenza virus type A. In the vapor phase, C. bergamia and M. alternifolia strongly reduced viral cytopathic effect without exerting any cytotoxicity. The E. globulus vapor EO reduced viral infection by 78% with no cytotoxicity, while I. verum was not effective. Furthermore, we characterized the EOs and their vapor phase by the head-space gas chromatography–mass spectrometry technique, observing that the major component found in each liquid EO is the same one of the corresponding vapor phases, with the exception of M. alternifolia. To deepen the mechanism of action, the morphological integrity of virus particles was checked by negative staining transmission electron microscopy, showing that they interfere with the lipid bilayer of the viral envelope, leading to the decomposition of membranes. We speculated that the most abundant components of the vapor EOs might directly interfere with influenza virus envelope structures or mask viral structures important for early steps of viral infection. 相似文献
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Roberta Seraglia Giovanni Sartore Raffaella Marin Silvia Burlina Enzo Manzato Eugenio Ragazzi Pietro Traldi Annunziata Lapolla 《Journal of mass spectrometry : JMS》2013,48(1):105-110
Increased oxidation of low density lipoprotein (LDL) is characteristic of atherosclerosis. In this frame, high density lipoproteins (HDL) play an important role, being able to remove lipid peroxides (LPOs) and cholesterol from oxidized LDL, so exhibiting a protective role against atherosclerosis. A wide range of reactive compounds lead to the oxidation of methionine (Met) residues with the formation of methionine sulphoxide (MetO) in apolipoprotein A‐I (ApoA‐I). Consequently, the determination of MetO level can give both an evaluation of oxidative stress and the reduced capability of ApoA‐I in LPOs and cholesterol transport. For these reasons, the development of analytical methods able to determine the MetO level is surely of interest, and we report here the results obtained by MALDI mass spectrometry. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献