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301.
Cataldo Simari Vincenzo Baglio Carmelo Lo Vecchio Antonino S. Aricò Raffaele G. Agostino Luigi Coppola Cesare Oliviero Rossi Isabella Nicotera 《Ionics》2017,23(8):2113-2123
Hybrid nanomaterial based on the combination between a 2D silicate structure of a smectic clay (SWy) and 1D structures of carbon nanotubes has been synthesized and used as additive in the polymer matrix of Nafion for the preparation of electrolyte nanocomposite membranes. The CNTs anchored on the clay’s lamellae were subsequently oxidized and organo-functionalized by sulphonic groups. The hybrid membranes have been tested in direct methanol fuel cells (DMFCs) and studied by NMR spectroscopy (pulse field gradient technique and relaxation times), electrochemical impedance spectroscopy and SEM microscopy. The study of the molecular dynamics of methanol and protons, as well as the tests in the DMFC, shows the effectiveness of these “branched particles” for the reduction of the methanol crossover, whilst ensuring appropriate proton conductivity, especially in conditions of low humidity and high temperature (>100 °C). 相似文献
302.
Sandrine Ongeri Umberto Piarulli Maryline Roux Chiara Monti Cesare Gennari 《Helvetica chimica acta》2002,85(10):3388-3399
The synthesis of the new chiral ligands 6ae, 8ae, 9ae , and 11ae starting from the chiral β‐[(Boc)amino]sulfonamide 3ae is reported. The β‐amino group of 3ae was deprotected and condensed with 3,5‐dichlorosalicylaldehyde ( 4 ) to yield the known Schiff base 5ae , which was then reduced to the amino compound 6ae (Scheme 3). Alternatively, condensation of the free amino compound with 2‐(diphenylphosphanyl)benzaldehyde ( 7 ) afforded the imino ligand 8ae which upon reduction yielded the amino ligand 9ae (Scheme 4). The free amino compound derived from 3ae was also coupled with 2‐(diphenylphosphanyl)benzoic acid ( 10 ) to give ligand 11ae (Scheme 5). These ligands were tested in the copper‐catalysed allylic substitution reaction of cinnamyl (=3‐phenylprop‐2‐enyl) phosphate 12 with diethylzinc as a nucleophile. Ligands 5ae, 6ae, 8ae , and 11ae gave excellent ratios (100 : 0) of the SN2′/SN2 products (Scheme 6 and Table 1). Ligand 11ce , identified from the screening of a small library of ligands of general formula 11 , promoted the allylic substitution reaction with moderate enantioselectivity (40% for the SN2′ product 13 (Scheme 8 and Table 3)). 相似文献
303.
Maria Francesca Colella Rosachiara Antonia Salvino Martina Gaglian Federica Litrenta Cesare Oliviero Rossi Adolfo Le Pera Giuseppina De Luca 《Molecules (Basel, Switzerland)》2022,27(11)
Cannabis sativa is a herbaceous multiple-use species commonly employed to produce fiber, oil, and medicine. It is now becoming popular for the high nutritional properties of its seed oil and for the pharmacological activity of its cannabinoid fraction in inflorescences. The present study aims to apply nuclear magnetic resonance (NMR) spectroscopy to provide useful qualitative and quantitative information on the chemical composition of seed and flower Cannabis extracts obtained by ultra-sound-assisted extraction, and to evaluate NMR as an alternative to the official procedure for the quantification of cannabinoids. The estimation of the optimal ω-6/ω-3 ratio from the 1H NMR spectrum for the seed extracts of the Futura 75 variety and the quantitative results from the 1H and 13C NMR spectra for the inflorescence extracts of the Tiborszallasi and Kompolti varieties demonstrate that NMR technology represents a good alternative to classical chromatography, supplying sufficiently precise, sensitive, rapid, and informative data without any sample pre-treatment. In addition, different extraction procedures were tested and evaluated to compare the elaboration of spectral data with the principal component analysis (PCA) statistical method and the quantitative NMR results: the extracts obtained with higher polarity solvents (acetone or ethanol) were poor in psychotropic agents (THC < LOD) but had an appreciable percentage of both cannabinoids and triacylgliceroles (TAGs). These bioactive-rich extracts could be used in the food and pharmaceutical industries, opening new pathways for the production of functional foods and supplements. 相似文献
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307.
André Raposo Moreira Dias Arianna Pina Amelia Dean Dr. Hans-Georg Lerchen Dr. Michele Caruso Dr. Fabio Gasparri Dr. Ivan Fraietta Dr. Sonia Troiani Dr. Daniela Arosio Prof. Dr. Laura Belvisi Dr. Luca Pignataro Dr. Alberto Dal Corso Prof. Dr. Cesare Gennari 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(7):1696-1700
This work takes advantage of one of the hallmarks of cancer, that is, the presence of tumor infiltrating cells of the immune system and leukocyte-secreted enzymes, to promote the activation of an anticancer drug at the tumor site. The peptidomimetic integrin ligand cyclo(DKP-RGD) was found to accumulate on the surface of αvβ3 integrin-expressing human renal cell carcinoma 786-O cells. The ligand was conjugated to the anticancer drug paclitaxel through a Asn-Pro-Val (NPV) tripeptide linker, which is a substrate of neutrophil-secreted elastase. In vitro linker cleavage assays and cell antiproliferative experiments demonstrate the efficacy of this tumor-targeting conjugate, opening the way to potential therapeutic applications. 相似文献
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309.
Valeria M. Nurchi Guido Crisponi Tiziana Pivetta Enzo Tramontano Flaminia Cesare Marincola Joanna I. Lachowicz 《Polyhedron》2009
The complex formation equilibria of aspergillic acid with iron(III) were studied by potentiometric and spectrophotometric methods. The ligand was prepared by a biosynthetic route and its purity checked by MS and 1H NMR spectroscopies. Some structural features of the ligand are discussed on the basis of NMR results. The iron(III) coordination model is compared with those of two other cyclic hydroxamates, 1-hydroxy-2-pyridinone and 1,4-dihydroxy-2-pyridinone, and its features are discussed on the basis of quantum chemical calculations. 相似文献
310.
GUAN Yong-Jing M.de Cesare F.Terrasi F.Quinto C.Sabbarese N.de Cesare A.D'Onofrio WANG Hui-Juan 《中国物理C(英文版)》2010,34(11)
In order to measure the isotopic ratio of actinides,the upgrade of the accelerator mass spectrometry system at the Center for Isotopic Research on Cultural and Environmental heritage at the Second University of Naples,Italy,was performed.The beam emittance of 238U and the isotopic abundance sensitivity of 236U were measured on the present beam line.Utilizing a 16-strip silicon detector,the sensitivity of 236U/238U≈ 1×10-11 was obtained. 相似文献