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91.
Ferrocenyl‐Coupled N‐Heterocyclic Carbene Complexes of Gold(I): A Successful Approach to Multinuclear Anticancer Drugs 下载免费PDF全文
Dr. Julienne K. Muenzner Dr. Bernhard Biersack Alexander Albrecht Tobias Rehm Dr. Ulrike Lacher Dr. Wolfgang Milius Prof. Dr. Angela Casini Dr. Jing‐Jing Zhang Prof. Dr. Ingo Ott Prof. Dr. Viktor Brabec Olga Stuchlikova Dr. Ion C. Andronache Leonard Kaps Prof. Dr. Dr. Detlef Schuppan Prof. Dr. Rainer Schobert 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(52):18953-18962
Four gold(I) carbene complexes featuring 4‐ferrocenyl‐substituted imidazol‐2‐ylidene ligands were investigated for antiproliferative and antivascular properties. They were active against a panel of seven cancer cell lines, including multidrug‐resistant ones, with low micromolar or nanomolar IC50 (72 h) values, according to their lipophilicity and cellular uptake. The delocalized lipophilic cationic complexes 8 and 10 acted by increasing the reactive oxygen species in two ways: through a genuine ferrocene effect and by inhibiting the thioredoxin reductase. Both complexes gave rise to a reorganization of the F‐actin cytoskeleton in endothelial and melanoma cells, associated with a G1 phase cell cycle arrest and a retarded cell migration. They proved antiangiogenic in tube formation assays with endothelial cells and vascular‐disruptive on real blood vessels in the chorioallantoic membrane of chicken eggs. Biscarbene complex 10 was also tolerated well by mice where it led to a volume reduction of xenograft tumors by up to 80 %. 相似文献
92.
Magnus Pfaffenbach Dipl.‐Wirtschaftsing. Alexander Roller Prof. Dr. Tanja Gaich 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(25):8444-8447
Herein, we report the synthetically practical, short, and general access to novel indolophane architectures by means of a photochemical C?H activation process—the Witkop cyclization. These highly strained scaffolds were obtained by photoinduced ring closure and feature atropisomerism as well as aromatic ring current effects, which both have been investigated. The prevailing regioselectivity of theWitkop cyclization reaction was completely reversed by the presence of a quaternary carbon center, exerting a strong Thorpe–Ingold effect on the system for which experimental‐evidence is provided. 相似文献
93.
Molecular dynamics simulation of poly(3‐hexylthiophene) helical structure In Vacuo and in amorphous polymer surrounding 下载免费PDF全文
Natalia I. Borzdun Sergey V. Larin Stanislav G. Falkovich Victor M. Nazarychev Igor V. Volgin Alexander V. Yakimansky Alexey V. Lyulin Vikas Negi Peter A. Bobbert Sergey V. Lyulin 《Journal of Polymer Science.Polymer Physics》2016,54(23):2448-2456
The stability of poly(3‐hexylthiophene) (P3HT) helical structure has been investigated in vacuo and in amorphous polymer surrounding via molecular dynamics‐based simulations at temperatures below and above the P3HT melting point. The results show that the helical chain remains stable at room temperature both in vacuo and in amorphous surrounding, and promptly loses its structure at elevated temperatures. However, the amorphous surrounding inhibits the destruction of the helix at higher temperatures. In addition, it is shown that the electrostatic interactions do not significantly affect the stability of the helical structure. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 2448–2456 相似文献
94.
Alexander M. Khenkin Gregory Leitus Lev Weiner Ronny Neumann 《Journal of Cluster Science》2014,25(3):687-693
The tri-rhenium(VI) capped Wells–Dawson polyoxometalate, [Re3P2W15O62]6– with quaternary ammonium cations was synthesized by reacting the trivacant lacunary species, [P2W15O56]12– with [ReOCl3(PPh3)2] in an organic solvent. Elemental analysis by thermogravimetry and inductively coupled plasma mass spectroctrometry confirmed the substitution of three rhenium atoms, single-crystal X-ray diffraction as well as infra red spectroscopy showed the complete Wells–Dawson structure. The presence of all three rhenium atoms in one cap is indicated by 31P nuclear magnetic resonance spectroscopy and the electron spin resonance spectrum shows that the tri-rhenium(V) species with three unpaired electrons is low spin, S = ½. 相似文献
95.
96.
Antonia Wachter-Zeh Alexander Zeh Martin Bossert 《Designs, Codes and Cryptography》2014,71(2):261-281
A new probabilistic decoding algorithm for low-rate interleaved Reed–Solomon (IRS) codes is presented. This approach increases the error correcting capability of IRS codes compared to other known approaches (e.g. joint decoding) with high probability. It is a generalization of well-known decoding approaches and its complexity is quadratic with the length of the code. Asymptotic parameters of the new approach are calculated and simulation results are shown to illustrate its performance. Moreover, an upper bound on the failure probability is derived. 相似文献
97.
98.
99.
Redox and Coordination Behavior of the Hexaphosphabenzene Ligand in [(Cp*Mo)2(μ,η6:η6‐P6)] Towards the “Naked” Cations Cu+, Ag+, and Tl+ 下载免费PDF全文
Martin Fleischmann Fabian Dielmann Laurence J. Gregoriades Eugenia V. Peresypkina Alexander V. Virovets Sebastian Huber Alexey Y. Timoshkin Gbor Balzs Manfred Scheer 《Angewandte Chemie (International ed. in English)》2015,54(44):13110-13115
Although the cyclo‐P6 complex [(Cp*Mo)2(μ,η6:η6‐P6)] ( 1 ) was reported 30 years ago, little is known about its chemistry. Herein, we report a high‐yielding synthesis of 1 , the complex 2 , which contains an unprecedented cyclo‐P10 ligand, and the reactivity of 1 towards the “naked” cations Cu+, Ag+, and Tl+. Besides the formation of the single oxidation products 3 a,b which have a bisallylic distorted cyclo‐P6 middle deck, the [M( 1 )2]+ complexes are described which show distorted square‐planar (M=Cu( 4 a ), Ag( 4 b )) or distorted tetrahedral coordinated (M=Cu( 5 )) M+ cations. The choice of solvent enabled control over the reaction outcome for Cu+, as proved by powder XRD and supported by DFT calculations. The reaction with Tl+ affords a layered two‐dimensional coordination network in the solid state. 相似文献
100.
Experimental Charge Density Evidence for Pnicogen Bonding in a Crystal of Ammonium Chloride 下载免费PDF全文
Dr. Yulia V. Nelyubina Prof. Alexander A. Korlyukov Prof. Konstantin A. Lyssenko 《Chemphyschem》2015,16(3):676-681
Chemical binding in crystalline ammonium chloride, a simple inorganic salt with an unexpectedly complex bonding pattern, was studied by using a topological analysis of electron density function derived from high‐resolution X‐ray diffraction. Supported by periodic quantum chemical calculations, it provided experimental evidence for weak σ‐hole bonds (1.5 kcal mol?1) that involve ammonium cations in a crystal. Our results show this type of supramolecular interaction to be more numerous than has been found to date by using gas‐phase calculations or statistical analysis of CSD. 相似文献