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Triggering the Directional Selectivity of a Ring‐Closure Reaction Leads to Pyridoazacarbazoles with Anticancer Properties 下载免费PDF全文
Tamara N. Steinhauer Daniel S. Längle Dr. Christopher Meier Dr. Ulrich Girreser Dr. Lars Stenzel Prof. Dr. Dieter Heber Prof. Dr. Bernd Clement 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(18):6668-6672
We herein describe a facile and versatile synthetic route to the tetracyclic system of 6‐substituted 5,6‐dihydro‐11H‐pyrido[3,2‐i]‐1‐azacarbazoles with promising anticancer properties. These derivatives are built up by an elegant one‐step base‐catalyzed synthetic procedure from commercially available building blocks. One additional step provides the corresponding skeleton hitherto unknown in the literature. The possibility to synthesize a large library of compounds with various substitution patterns utilizing this method underlines the importance of this synthetic procedure. 相似文献
3.
Tamara Bezrodna Georgyi Klishevich Volodymyr Melnyk Vira Nesprava Olexandr Roshchin 《Molecular Crystals and Liquid Crystals》2020,697(1):60-67
AbstractFluorescence and absorption spectra of the 2-fluoronaphthalene admixtures in naphthalene were studied at low temperature (T?=?4.2 К). Two types of pairwise impurity centers were formed at admixture concentrations of more than 1?wt%. Polarization of absorption bands was detected; these spectra were determined by resonance interactions between molecules of the impurity center. Resonant splitting of electronic levels for the translationally nonequivalent molecules in the unit cell of the naphthalene crystal was analyzed for the case, when one molecule was in the similar phase with the incident light wave and the other one was in antiphase. 相似文献
4.
Tamara Alhilfi Pierre Chambon Steve P. Rannard 《Journal of polymer science. Part A, Polymer chemistry》2020,58(10):1426-1438
Ambient temperature-initiated anionic polymerization has generated branched polystyrenes of varying molecular weights and architectures by inclusion of a distyryl branching comonomer into a conventional sec-Butylithium-initiated polymerization of styrene. Primary chain length control within the branched polymers, and restriction of the branching points to varying segments of the primary chains, led to variations of glass transition temperature with no direct correlation to the branched polymer molecular weight but a strong relationship to the length of individual chains comprising the branched macromolecules. 相似文献
5.
Tanja Vidaković-Koch Tamara Miličić Luka A. Živković Hoon Seng Chan Ulrike Krewer Menka Petkovska 《Current Opinion in Electrochemistry》2021
The nonlinear frequency response analysis (NFRA) can be seen as an extension of electrochemical impedance spectroscopy. NFRA gives a full and detailed representation of the system response and can establish a connection between model parameters and the experimentally observed phenomena. In this article, different theoretical NFRA approaches and the most recent application examples are discussed. A simple electrochemical example is used to showcase the benefits and disadvantages of analyzing the system response by using different approaches. In addition, it was shown how to extract experimental harmonic values and analyze them. 相似文献
6.
Rozhkov A. V. Basova G. V. Korshunov A. O. Bochkarev L. N. Glukhova T. A. Il´ichev V. A. 《Russian Chemical Bulletin》2015,64(8):1949-1954
Russian Chemical Bulletin - New norbornene monomer, viz., 5-[(bicyclo[2.2.1]hept-5-en-2-ylmethoxy)methyl]-8-[(dimesitylboryl)oxy]quinoline (1), was synthesized. The copolymers based on monomer 1... 相似文献
7.
Dr. Samuel M. Meier M. Sc. Dominique Kreutz Dr. Lilli Winter M. Sc. Matthias H. M. Klose M. Sc. Klaudia Cseh M. Sc. Tamara Weiss Dr. Andrea Bileck M. Sc. Beatrix Alte Dr. Johanna C. Mader M. Sc. Samir Jana Dr. Annesha Chatterjee Dr. Arindam Bhattacharyya Michaela Hejl Dr. Michael A. Jakupec Priv.-Doz. Dr. Petra Heffeter Prof. Dr. Walter Berger Prof. Dr. Christian G. Hartinger Prof. Dr. Bernhard K. Keppler Prof. Dr. Gerhard Wiche Prof. Dr. Christopher Gerner 《Angewandte Chemie (International ed. in English)》2017,56(28):8267-8271
Organometallic metal(arene) anticancer agents require ligand exchange for their anticancer activity and this is generally believed to confer low selectivity for potential cellular targets. However, using an integrated proteomics-based target-response profiling approach as a potent hypothesis-generating procedure, we found an unexpected target selectivity of a ruthenium(arene) pyridinecarbothioamide (plecstatin) for plectin, a scaffold protein and cytolinker, which was validated in a plectin knock-out model in vitro. Plectin targeting shows potential as a strategy to inhibit tumor invasiveness as shown in cultured tumor spheroids while oral administration of plecstatin-1 to mice reduces tumor growth more efficiently in the invasive B16 melanoma than in the CT26 colon tumor model. 相似文献
8.
A.?S.?SukhikhEmail author T.?V.?Basova S.?A.?Gromilov 《Journal of Structural Chemistry》2017,58(5):953-963
An approach for the substantiated choice of the indexing procedure of a diffraction pattern is described. The technique is based on a combined use of powder X-ray diffraction data in Bragg–Brentano schemes and 2D GIXD of mainly oriented polycrystalline samples. 相似文献
9.
Tamara?L.?Church Alma?Berenice?Jasso-Salcedo Fredrik?Bj?rnerb?ck Niklas?HedinEmail author 《中国科学:化学(英文版)》2017,60(8):1033-1055
Microporous polymers (MPs) are studied for their intriguing chemistry and physics as well as their potential application in catalytic transformations, gas-separation processes, water purification and so on. Here, we critically review MPs with respect to the sustainability aspects of their synthesis as well as their applications that have sustainable character. Some MPs have been synthesized from monomers derived from biomass resources, but there is certainly a large potential for further developments. There are also opportunities to improve the sustainability of MP synthesis in terms of the use of solvents, catalysts, and related aspects. The applications of MPs in processes related to sustainability depend upon multiple properties. A rich and flexible chemistry is important to applications as catalysts for, among other useful reactions, the photoreduction of CO2 and selective oxidation. The (ultra)micropore volume of MPs are crucial in gas-separation applications such as CO2 capture, and the chemisorption of CO2 on MP-tethered alkylamines could offer a means to remove that gas from dilute mixtures. When it comes to the storage of H2 and CH4 in MPs for onboard use in fuel cell or biogas cars, volumetric capacity is paramount, meaning that the density of the MPs must be considered. Finally, for use in separation and purifications from liquid mixtures (aqueous or hydrocarbon-based), crosslinked MPs are more limited than the solution-processable MPs that can be more easily processed into films and membranes. 相似文献
10.
Tuniyazi Abuduaini Vincent Roy Julien Marlet Catherine Gaudy-Graffin Denys Brand Ccile Baronti Franck Touret Bruno Coutard Tamara R. McBrayer Raymond F. Schinazi Luigi A. Agrofoglio 《Molecules (Basel, Switzerland)》2021,26(5)
A series of hitherto unknown (1,4-disubstituted-1,2,3-triazol)-(E)-2-methyl-but-2-enyl nucleosides phosphonate prodrugs bearing 4-substituted-1,2,3-triazoles were prepared in a straight approach through an olefin acyclic cross metathesis as the key synthetic step. All novel compounds were evaluated for their antiviral activities against HBV, HIV and SARS-CoV-2. Among these molecules, only compound 15j, a hexadecyloxypropyl (HDP)/(isopropyloxycarbonyl-oxymethyl)-ester (POC) prodrug, showed activity against HBV in Huh7 cell cultures with 62% inhibition at 10 μM, without significant cytotoxicity (IC50 = 66.4 μM in HepG2 cells, IC50 = 43.1 μM in HepG2 cells) at 10 μM. 相似文献