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21.
Muñiz K 《Chemical Society reviews》2004,33(3):166-174
Imido complexes of osmium tetroxide are versatile compounds for olefin functionalisation. This tutorial review offers a brief historical overview on these compounds and discusses the electronic properties and reactivities of isolated imido osmium compounds in what had been the original stoichiometric aminohydroxylation reaction. The recently emerging catalytic Sharpless aminohydroxylation is discussed with special emphasis on mechanistic details. The final section deals with diamination of olefins, which relies on the chemistry of bisimido and trisimido osmium complexes. 相似文献
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The COSY-TOF Collaboration F. Hauenstein E. Borodina H. Clement E. Doroshkevich R. Dzhygadlo K. Ehrhardt W. Eyrich W. Gast A. Gillitzer D. Grzonka S. Jowzaee P. Klaja L. Kober K. Kilian M. Krapp M. Mertens P. Moskal J. Ritman E. Roderburg M. Röder W. Schroeder T. Sefzick J. Smyrski P. Wintz P. Wüstner 《The European Physical Journal A - Hadrons and Nuclei》2016,52(11):337
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Dr. Kilian Colas A. Catarina V. D. dos Santos Dr. Stefanie V. Kohlhepp Dr. Abraham Mendoza 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(9):e202104053
The synthesis of ketones through addition of organometallic reagents to aliphatic carboxylic acids is a straightforward strategy that is limited to organolithium reagents. More desirable Grignard reagents can be activated and controlled with a bulky aniline-derived turbo-Hauser base. This operationally simple procedure allows the straightforward preparation of a variety of aliphatic and perfluoroalkyl ketones alike from functionalized alkyl, aryl and heteroaryl Grignard reagents. 相似文献
25.
Johura Ansary Francesca Giampieri Tamara Y. Forbes-Hernandez Lucia Regolo Denise Quinzi Santos Gracia Villar Eduardo Garcia Villena Kilian Tutusaus Pifarre Jos M. Alvarez-Suarez Maurizio Battino Danila Cianciosi 《Molecules (Basel, Switzerland)》2021,26(8)
In recent times, scientific attention has been paid to different foods and their bioactive components for the ability to inhibit the onset and progress of different types of cancer. Nigella sativa extract, powder and seed oil and its main components, thymoquinone and α-hederin, have showed potent anticancer and chemosensitizing effects against various types of cancer, such as liver, colon, breast, renal, cervical, lung, ovarian, pancreatic, prostate and skin tumors, through the modulation of various molecular signaling pathways. Herein, the purpose of this review was to highlight the anticancer activity of Nigella sativa and it constitutes, focusing on different in vitro, in vivo and clinical studies and projects, in order to underline their antiproliferative, proapoptotic, cytotoxic and antimetastatic effects. Particular attention has been also given to the synergistic effect of Nigella sativa and it constitutes with chemotherapeutic drugs, and to the synthesized analogs of thymoquinone that seem to enhance the chemo-sensitizing potential. This review could be a useful step towards new research on N. sativa and cancer, to include this plant in the dietary treatments in support to conventional therapies, for the best achievement of therapeutic goals. 相似文献
26.
Valeria Mantella Michal Strach Kilian Frank James R. Pankhurst Dragos Stoian Chethana Gadiyar Bert Nickel Raffaella Buonsanti 《Angewandte Chemie (International ed. in English)》2020,59(28):11627-11633
The classical nucleation theory (CNT) is the most common theoretical framework used to explain particle formation. However, nucleation is a complex process with reaction pathways which are often not covered by the CNT. Herein, we study the formation mechanism of copper nanospheres using in situ X‐ray absorption and scattering measurements. We reveal that their nucleation involves coordination polymer lamellae as pre‐nucleation structures occupying a local minimum in the reaction energy landscape. Having learned this, we achieved a superior monodispersity for Cu nanospheres of different sizes. This report exemplifies the importance of developing a more realistic picture of the mechanism involved in the formation of inorganic nanoparticles to develop a rational approach to their synthesis. 相似文献
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Brodowski W Bilger R Calén H Clement H Ekström C Fransson K Greiff J Häggström S Höistad B Johanson J Johansson A Johansson T Kilian K Kullander S Kupść A Marciniewski P Morosov B Oelert W Pätzold J Ruber RJ Schepkin M Scobel W Seluzhenkov I Stepaniak J Sukhanov A Turowiecki A Wagner GJ Wilhelmi Z Zabierowski J Zlomanczuk J 《Physical review letters》2002,88(19):192301
The pp-->pp pi(+) pi(-) reaction has been measured exclusively near threshold at CELSIUS. The total cross sections are nearly an order of magnitude lower than expected from previous inclusive measurements. The differential cross sections reveal pp-->pp(*)(1440)-->pp sigma = pp(pi(+)pi(-))(I = l = 0) as the dominant process as well as significant contributions from p(*)-->Delta(++)pi(-)-->psigma. The observed anisotropy in the proton angular dependence is consistent with heavy-meson exchange. In the invariant mass spectra, no narrow structures of statistical relevance (3sigma) are found. 相似文献
30.
New aspects of yielding in semicrystalline polymers related to microstructure: Branched polyethylene
The application of thermodynamics of eutectoid copolymers and a generalized Tabor-relation to relationships between mechanical properties (microhardness, yield stress) and microstructure in semicrystalline polymers is considered. The approach is illustrated by results on melt-crystallized low density polyethylene, investigated near the yield point at different temperatures. The success of the approach emphasizes that semicrystalline polymers, despite being viscoelastic hetereogeneous systems, give rise to a yielding process entailing the irreversible deformation of a larger number of crystals within cooperative super-structure units. Microhardness provides, within this context, a unique measure of the crystal size average. Comparison of calculated and experimental data favors the view of deformed crystals containing basal defective surface boundaries (meso-crystals) which yield cooperatively.Dedicated to Professor Dr. Dr. h. c. Armin Weiss on the occasion of his 60th birthday. 相似文献