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421.
Tuong Thi Le Xavier Framboisier Arnaud Aymes Armelle Ropars Jean-Pol Frippiat Romain Kapel 《Molecules (Basel, Switzerland)》2021,26(19)
In this study, phenolic compounds from an aqueous protein by-product from rapeseed meal (RSM) were identified by HPLC-DAD and HPLC-ESI-MS, including sinapine, sinapic acid, sinapoyl glucose, and 1,2-di-sinapoyl gentibiose. The main phenolic compound in this by-product was sinapine. We also performed acid hydrolysis to convert sinapine, and sinapic acid derivatives present in the permeate, to sinapic acid. The adsorption of phenolic compounds was investigated using five macroporous resins, including XAD4, XAD7, XAD16, XAD1180, and HP20. Among them, XAD16 showed the highest total phenolic contents adsorption capacities. The adsorption behavior of phenolic compounds was described by pseudo-second-order and Langmuir models. Moreover, thermodynamics tests demonstrated that the adsorption process of phenolic compounds was exothermic and spontaneous. The highest desorption ratio was obtained with 30% (v/v) and 70% (v/v) ethanol for sinapine and sinapic acid, respectively, with a desorption ratio of 63.19 ± 0.03% and 94.68 ± 0.013%. DPPH and ABTS tests revealed that the antioxidant activity of the hydrolyzed fraction was higher than the non-hydrolyzed fraction and higher than the one of vitamin C. Antioxidant tests demonstrated that these phenolic compounds could be used as natural antioxidants, which can be applied in the food industry. 相似文献
422.
Romain Blanchard Laurence Carassus Miklós Rásonyi 《Mathematical Methods of Operations Research》2018,88(2):241-281
We consider a discrete-time financial market model with finite time horizon and investors with utility functions defined on the non-negative half-line. We allow these functions to be random, non-concave and non-smooth. We use a dynamic programming framework together with measurable selection arguments to establish both the characterisation of the no-arbitrage property for such markets and the existence of an optimal portfolio strategy for such investors. 相似文献
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Hervé Dekkiche Antoine Buisson Adam Langlois Paul‐Ludovic Karsenti Prof. Laurent Ruhlmann Dr. Romain Ruppert Prof. Pierre Harvey 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(30):10484-10493
We report the preparation of several new porphyrin homodimers bridged by a platinum(II) ion in which very intense electronic communication through the coordination link occurs. Moreover, the synthesis of a new porphyrin dyad and its photophysical properties are reported. This dyad exhibits the fastest singlet energy transfer ever reported for synthetic systems between a zinc(II) porphyrin and a porphyrin free base. This extremely fast transfer (~100 femtoseconds) is in the same range as the fastest one measured in natural systems. This feature is due to the platinum(II) linker, which allows for strong MO couplings between the two porphyrin units as experimentally supported by electrochemistry and corroborated by DFT computations. 相似文献
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Asymmetric Hydroxylative Phenol Dearomatization Promoted by Chiral Binaphthylic and Biphenylic Iodanes
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Cyril Bosset Romain Coffinier Dr. Philippe A. Peixoto Mourad El Assal Dr. Karinne Miqueu Dr. Jean‐Marc Sotiropoulos Dr. Laurent Pouységu Prof. Stéphane Quideau 《Angewandte Chemie (International ed. in English)》2014,53(37):9860-9864
The long‐standing quest for chiral hypervalent organoiodine compounds (i.e., iodanes) as metal‐free reagents for asymmetric synthesis continues. Although remarkable progress has recently been made in organoiodine‐catalyzed reactions using a terminal oxidant in stoichiometric amounts, there is still a significant need for “flaskable” chiral iodane reagents. Herein, we describe the synthesis of new iodobinaphthyls and iodobiphenyls, their successful and selective DMDO‐mediated oxidation into either λ3‐ or λ5‐iodanes, and the evaluation of their capacity to promote asymmetric hydroxylative phenol dearomatization (HPD) reactions. Most notably, a C2‐symmetrical biphenylic λ5‐iodane promoted the HPD‐induced conversion of the monoterpene thymol into the corresponding ortho‐quinol‐based [4+2] cyclodimer (i.e., bis(thymol)) with enantiomeric excesses of up to 94 %. 相似文献
430.
Romain Liénard Julien De Winter Olivier Coulembier 《Journal of polymer science. Part A, Polymer chemistry》2020,58(11):1481-1502
Since the time first synthetic macrocycles were observed as academic curiosities, great advances have been made. Thanks to the development of controlled polymerization processes, new catalytic systems and characterization techniques during the last decades, well-defined cyclic polymers are now readily accessible. This further permits the determination of their unique set of properties, mainly due to their lack of chain ends, and their use for industrial applications can now be foreshadowed. This review aims to give an overview on the recent progresses in the field of ring polymers to this day. The current state of the art of the preparation of cyclic polymers, the challenges related to it such as the purification of the samples and the scalability of the synthetic processes, the properties arising from the cyclic topology and the potential use of cyclo-based polymers for biomedical applications are as many topics covered in this review. 相似文献