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41.
Truong Son Pham Katalin Gönczi György Kardos Krisztina Süle László Hegedűs Mihály Kállay Miklós Kubinyi Pál Szabó Imre Petneházy László Tőke Zsuzsa Jászay 《Tetrahedron: Asymmetry》2013,24(24):1605-1614
Several cinchona based squaramide catalysts were applied to the asymmetric Michael addition of α-nitroethylphosphonates to acrylic acid aryl esters, resulting in high yields and enantioselectivities. The absolute configuration of one of the quaternary α-nitrophosphonate adducts was deduced from its experimental and calculated CD spectra. The adducts were reduced to their cyclic aminophosphonates by catalytic hydrogenation. 相似文献
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In this article, we derive expressions for conditional expectations in terms of regular expectations without conditioning but involving some weights. For this purpose, we apply two approaches: the conditional density method and the Malliavin method. We use these expressions for the numerical estimation of the price of American options and their deltas in a Lévy and jump-diffusion setting. Several examples of applications to financial and energy markets are given including numerical examples. 相似文献
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Dr. Benoît Bertrand Dr. Candice Botuha Jérémy Forté Dr. Héloïse Dossmann Dr. Michèle Salmain 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(56):12846-12861
The two independent and coordination sites of a newly synthesized bis[2-(hydroxyphenyl)-1,2,4-triazole] platform have been exploited to prepare four monometallic neutral ()PtII complexes carrying DMSO, pyridine, triphenylphosphine, or N-heterocyclic carbene as the fourth ligand. Then, the second coordination site was used to introduce an IR-active rhenium tricarbonyl entity, affording the four corresponding heterobimetallic neutral PtII/ReI complexes, as well as a cationic PtII/ReI derivative. X-ray crystallographic studies showed that distortion of the organic platform occurred to accommodate the coordination geometry of both metal centers. No ligand exchange or transchelation occurred upon incubation of the PtII complexes in aqueous environment or in the presence of FeIII, respectively. The antiproliferative activity of the ligand and complexes was first screened on the triple-negative breast cancer cell line MDA-MB-231. Then, the IC50 values of the most active candidates were determined on a wider panel of human cancer cells (MDA-MB-231, MCF-7, and A2780), as well as on a nontumorigenic cell line (MCF-10A). Low micromolar activities were reached for the complexes carrying a DMSO ligand, making them the first examples of highly active, but hydrolytically stable, PtII complexes. Finally, the characteristic mid-IR signature of the {Re(CO)3} fragment in the Pt/Re heterobimetallic complexes was used to quantify their uptake in breast cancer cells. 相似文献
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Quantification of curium isotopes in environmental samples: drawbacks,speciation and specific tracer
Habibi Azza Le Corre Roselyne Wampach Aubert Christèle Fleury Sandrine Hennequet Patricia Augeray Céline Galliez Kévin Agarande Michelle 《Journal of Radioanalytical and Nuclear Chemistry》2021,329(2):545-554
Journal of Radioanalytical and Nuclear Chemistry - In this study, drawbacks of the use of 243Am as a tracer in order to quantify curium isotopes during a complex chemical procedure were... 相似文献
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Michèle Willson Jacques Navech Ramon Burgada 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):457-467
Abstract The PMR spectra of some spirophosphorans containing the P–C bond are analysed. The results allow us to determine the stereochemistry of these compounds (conformation, stereoisomerism). Le spectre de RMP de quelques spirophosphoranes à liaison P–C est analysé. Les résultats sont utilisés pour préciser la stéréochimie de ces composés (conformation, stéréoisomérie). 相似文献