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111.
Alla Zablotskaya Izolda Segal Mikhail Maiorov Dmitry Zablotsky Anatoly Mishnev Edmunds Lukevics Irina Shestakova Ilona Domracheva 《Journal of magnetism and magnetic materials》2007
Water-soluble double-coated magnetic nanoparticles (NPs) containing cytotoxic decyldimethyl(β-dimethylaminoethoxy)silane methiodide (AA) molecule sorbed at biocompatible magnetic particles, which consist of magnetite pre-coated with oleic acid (OA), have been prepared. X-ray line profile broadening analysis was used for crystallite size determination. The method of magnetogranulometry has been used for determination of diameter of iron oxide magnetic core and magnetic properties of NPs prepared. In vitro cytotoxicity on monolayer tumor cell lines HT-1080 (human fibrosarcoma), MG-22A (mouse hepatoma) and normal mouse fibroblasts (NIH 3T3) has been studied. It was revealed that all the water-based colloidal solutions obtained are non-toxic and possess high NO-induction ability. 相似文献
112.
Krasnov Victor P. Zarubaev Vladimir V. Gruzdev Dmitry А. Vozdvizhenskaya Olga А. Vakarov Sergey А. Musiyak Vera V. Chulakov Evgeny N. Volobueva Alexandrina S. Sinegubova Ekaterina O. Ezhikova Marina А. Kodess Mikhail I. Levit Galina L. Charushin Valery N. 《Chemistry of Heterocyclic Compounds》2021,57(4):498-504
Chemistry of Heterocyclic Compounds - A number of novel amides were synthesized by coupling of 6-[(9H-purin-6-yl)amino]hexanoic acid to heterocyclic amines. The antiviral activity of the obtained... 相似文献
113.
Kwan Ho Au-Yeung Tim Kühne Daniel Becker Dr. Marcus Richter Dr. Dmitry A. Ryndyk Prof. Dr. Gianaurelio Cuniberti Prof. Dr. Thomas Heine Prof. Dr. Xinliang Feng Dr. Francesca Moresco 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(69):17336-17340
The rapid development of on-surface synthesis provides a unique approach toward the formation of carbon-based nanostructures with designed properties. Herein, we present the on-surface formation of CN-substituted phenylene vinylene chains on the Au(111) surface, thermally induced by annealing the substrate stepwise at temperatures between 220 °C and 240 °C. The reaction is investigated by scanning tunneling microscopy and density functional theory. Supported by the calculated reaction pathway, we assign the observed chain formation to a Knoevenagel condensation between an aldehyde and a methylene nitrile substituent. 相似文献
114.
115.
Dr. Dmitry Katayev Kai F. Pfister Timo Wendling Prof. Dr. Lukas J. Gooßen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(32):9902-9905
Various (hetero)arenecarboxylic acids were converted to the corresponding Daugulis amides and nitrated selectively in the ortho‐position in the presence of [CuNO3(PPh3)2] and AgNO2 at 50 °C. A microwave‐assisted saponification allows regenerating the carboxylate group within minutes, which may then be removed tracelessly by protodecarboxylation, or substituted by aryl‐ or alkoxy‐groups via decarboxylative cross‐coupling. 相似文献
116.
Pyranoside‐into‐Furanoside Rearrangement: New Reaction in Carbohydrate Chemistry and Its Application in Oligosaccharide Synthesis
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Dr. Vadim B. Krylov Dmitry A. Argunov Dmitry Z. Vinnitskiy Stella A. Verkhnyatskaya Dr. Alexey G. Gerbst Dr. Nadezhda E. Ustyuzhanina Dr. Andrey S. Dmitrenok Prof. Dr. Johannes Huebner Prof. Dr. Otto Holst Prof. Dr. Hans‐Christian Siebert Prof. Dr. Nikolay E. Nifantiev 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(50):16516-16522
Great interest in natural furanoside‐containing compounds has challenged the development of preparative methods for their synthesis. Herein a novel reaction in carbohydrate chemistry, namely a pyranoside‐into‐furanoside (PIF) rearrangement permitting the transformation of selectively O‐substituted pyranosides into the corresponding furanosides is reported. The discovered process includes acid‐promoted sulfation accompanied by rearrangement of the pyranoside ring into a furanoside ring followed by solvolytic O‐desulfation. This process, which has no analogy in organic chemistry, was shown to be a very useful tool for the synthesis of furanoside‐containing complex oligosaccharides, which was demonstrated by synthesizing disaccharide derivatives α‐D ‐Galp‐(1→3)‐β‐D ‐ Galf ‐OPr, 3‐O‐s ‐lactyl‐β‐D ‐ Galf ‐(1→3)‐β‐D ‐Glcp‐OPr, and α‐L ‐ Fucf ‐(1→4)‐β‐D ‐GlcpA‐OPr related to polysaccharides from the bacteria Klebsiella pneumoniae and Enterococcus faecalis and the brown seaweed Chordaria flagelliformis. 相似文献
117.
Palladium–N‐Heterocyclic Carbene (NHC)‐Catalyzed Asymmetric Synthesis of Indolines through Regiodivergent C(sp3)H Activation: Scope and DFT Study
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Dmitry Katayev Dr. Evgeny Larionov Dr. Masafumi Nakanishi Dr. Céline Besnard Prof. Dr. E. Peter Kündig 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(46):15021-15030
Two bulky, chiral, monodentate N‐heterocyclic carbene ligands were applied to palladium‐catalyzed asymmetric C?H arylation to incorporate C(sp3)?H bond activation. Racemic mixtures of the carbamate starting materials underwent regiodivergent reactions to afford different trans‐2,3‐substituted indolines. Although this CAr?Calkyl coupling requires high temperatures (140–160 °C), chiral induction is high. This regiodivergent reaction, when carried out with enantiopure starting materials, can lead to single structurally different enantiopure products, depending on the catalyst chirality. The C?H activation at a tertiary center was realized only in the case of a cyclopropyl group. No C?H activation takes place alpha to a tertiary center. A detailed DFT study is included and analyses of methyl versus methylene versus methine C?H activation is used to rationalize experimentally observed regio‐ and enantioselectivities. 相似文献
118.
Pengpeng Liu Dr. Patrik Neuhaus Dr. Dmitry V. Kondratuk Prof. T. Silviu Balaban Prof. Harry L. Anderson 《Angewandte Chemie (International ed. in English)》2014,53(30):7770-7773
α‐ and β‐Cyclodextrins have been used as scaffolds for the synthesis of six‐ and seven‐legged templates by functionalizing every primary CH2OH with a 4‐pyridyl moiety. Although these templates are flexible, they are very effective for directing the synthesis of macrocyclic porphyrin oligomers consisting of six or seven porphyrin units. The transfer of chirality from the cyclodextrin templates to their nanoring hosts is evident from NMR and circular dichroism spectroscopy. Surprisingly, the mean effective molarity for binding the flexible α‐cyclodextrin‐based template within the six‐porphyrin nanoring (74 M ) is almost as high as for the previously studied rigid hexadentate template (180 M ). The discovery that flexible templates are effective in this system, and the availability of a template with a prime number of binding sites, open up many possibilities for the template‐directed synthesis of larger macrocycles. 相似文献
119.
Macromolecule Loading into Spherical,Elliptical, Star‐Like and Cubic Calcium Carbonate Carriers
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Dr. Bogdan V. Parakhonskiy Dr. Alexey M. Yashchenok Dr. Senem Donatan Dr. Dmitry V. Volodkin Dr. Francesco Tessarolo Prof. Renzo Antolini Prof. Helmuth Möhwald Prof. Andre G. Skirtach 《Chemphyschem》2014,15(13):2817-2822
We fabricated calcium carbonate particles with spherical, elliptical, star‐like and cubical morphologies by varying relative salt concentrations and adding ethylene glycol as a solvent to slow down the rate of particle formation. The loading capacity of particles of different isotropic (spherical and cubical) and anisotropic (elliptical and star‐like) geometries is investigated, and the surface area of such carriers is analysed. Potential applications of such drug delivery carriers are highlighted. 相似文献
120.
We compare three one-dimensional Nernst–Planck–Poisson systems that describe ion distribution near the electrode surfaces with planar, cylindrical and spherical symmetry respectively. These three models take into account ion diffusion and migration. In particular they describe the diffusive layers formed by Li+ ions in the vicinity of the graphite electrode particles. The three types of symmetry appear due to three different ways of particle ordering inside the electrode. In this paper we construct the exact steady state solutions to these systems and approximate solutions in form of power series. Then we solve the systems numerically and compare the results. We discuss the influence of symmetry in electrode particle ordering on the steady state distribution of ions in the diffusive layer. 相似文献