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151.
Bo Zhang Dr. Benjamin H. Fraser Mitchell A. Klenner Zhen Chen Prof. Steven H. Liang Prof. Massimiliano Massi Prof. Andrea J. Robinson Dr. Giancarlo Pascali 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(32):7613-7617
Fluorine-18 is the most utilized radioisotope in positron emission tomography (PET), but the wide application of fluorine-18 radiopharmaceuticals is hindered by its challenging labelling conditions. As such, many potentially important radiotracers remain underutilized. Herein, we describe the use of [18F]ethenesulfonyl fluoride (ESF) as a novel radiofluoride relay reagent that allows radiofluorination reactions to be performed in minimally equipped satellite nuclear medicine centres. [18F]ESF has a simple and reliable production route and can be stored on inert cartridges. The cartridges can then be shipped remotely and the trapped [18F]ESF can be liberated by simple solvent elution. We have tested 18 radiolabelling precursors, inclusive of model and clinically used structures, and most precursors have demonstrated comparable radiofluorination efficiencies to those obtained using a conventionally dried [18F]fluoride source. 相似文献
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Methyl 2-Br-2-Cl-carboxylates afford 2-alkyl-2-Cl-4-Br-carboxylates in fair yields by reaction with terminal alkenes, under mild conditions, through a radical process promoted by CuBr/Fe0 in DMF/CH2C12. 相似文献
156.
The solvatochromic behaviour of different functional group-bearing and self-interacting polyalkylthiophenes with strong chromic responses in solution and self-assembling capacity in the solid state is investigated here. The menagerie of species deriving from the conformational freedom of the conjugated chains in solution has been examined in different solvent mixtures as their physico-chemical nature sensibly affects final material morphology in the solid (film) state. Memory of solution curling shape and of the degree of aggregation is in fact retained through casting or spin-coating procedures and permanently endures in the polymeric film. The efficiency of the final device based on the ICP (inherent conducting polymer) film may therefore be improved by simply acting on its morphology, which is directly determined by polymer dissolution conditions. 相似文献
157.
Cinzia Forni Massimiliano Rossi Ilaria Borromeo Giordana Feriotto Giovambattista Platamone Claudio Tabolacci Carlo Mischiati Simone Beninati 《Molecules (Basel, Switzerland)》2021,26(12)
Nutraceuticals are biologically active molecules present in foods; they can have beneficial effects on health, but they are not available in large enough quantities to perform this function. Plant metabolites, such as polyphenols, are widely diffused in the plant kingdom, where they play fundamental roles in plant development and interactions with the environment. Among these, flavonoids are of particular interest as they have significant effects on human health. In vitro and/or in vivo studies described flavonoids as essential nutrients for preventing several diseases. They display broad and promising bioactivities to fight cancer, inflammation, bacterial infections, as well as to reduce the severity of neurodegenerative and cardiovascular diseases or diabetes. Therefore, it is not surprising that interest in flavonoids has sharply increased in recent years. More than 23,000 scientific publications on flavonoids have described the potential anticancer activity of these natural molecules in the last decade. Studies, in vitro and in vivo, show that flavonoids exhibit anticancer properties, and many epidemiological studies confirm that dietary intake of flavonoids leads to a reduced risk of cancer. This review provides a glimpse of the mechanisms of action of flavonoids on cancer cells. 相似文献
158.
In this paper we introduce two new quantifiers for the stock market inefficiency: the number of forbidden patterns and the normalized permutation entropy. They are model-independent measures, thus they have more general applicability. We find robust evidence that degree of market inefficiency is positively correlated with the number of forbidden patterns and negatively correlated with the permutation entropy. Our empirical results suggest that these two physical tools are useful to discriminate the stage of stock market development and can be easily implemented. 相似文献
159.
Meccanica - We present a simple representation of the hydrodynamic Green functions grounded on the free propagation of a vector field without any constraints (such as incompressibility) coupled... 相似文献
160.
Starting from the N-particle Nelson Hamiltonian defined by imposing an ultraviolet cutoff, we perform ultraviolet renormalization by showing that in the ultraviolet cutoff limit a self-adjoint operator exists after a logarithmically divergent term is subtracted from the original Hamiltonian. We obtain this term as the diagonal part of a pair interaction appearing in the density of a Gibbs measure derived from the Feynman–Kac representation of the Hamiltonian. Also, we show existence of a weak coupling limit of the renormalized Hamiltonian and derive an effective Yukawa interaction potential between the particles. 相似文献