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1.
Tobramycin and Nebramine as Pseudo‐oligosaccharide Scaffolds for the Development of Antimicrobial Cationic Amphiphiles 下载免费PDF全文
Yifat Berkov‐Zrihen Ido M. Herzog Raphael I. Benhamou Dr. Mark Feldman Kfir B. Steinbuch Pazit Shaul Dr. Shachar Lerer Dr. Avigdor Eldar Dr. Micha Fridman 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(11):4340-4349
Antimicrobial cationic amphiphiles derived from aminoglycoside pseudo‐oligosaccharide antibiotics interfere with the structure and function of bacterial membranes and offer a promising direction for the development of novel antibiotics. Herein, we report the design and synthesis of cationic amphiphiles derived from the pseudo‐trisaccharide aminoglycoside tobramycin and its pseudo‐disaccharide segment nebramine. Antimicrobial activity, membrane selectivity, mode of action, and structure–activity relationships were studied. Several cationic amphiphiles showed marked antimicrobial activity, and one amphiphilic nebramine derivative proved effective against all of the tested strains of bacteria; furthermore, against several of the tested strains, this compound was well over an order of magnitude more potent than the parent antibiotic tobramycin, the membrane‐targeting antimicrobial peptide mixture gramicidin D, and the cationic lipopeptide polymyxin B, which are in clinical use. 相似文献
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Dendritic Glycopolymer as Drug Delivery System for Proteasome Inhibitor Bortezomib in a Calcium Phosphate Bone Cement: First Steps Toward a Local Therapy of Osteolytic Bone Lesions 下载免费PDF全文
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Henri de Maissin Philipp R. Groß Obaid Mohiuddin Dr. Moritz Weigt Luca Nagel Marvin Herzog Zirun Wang Robert Willing Dr. Wilfried Reichardt Dr. Martin Pichotka Dr. Lisa Heß Prof. Dr. Thomas Reinheckel Prof. Dr. Henning J. Jessen Prof. Dr. Robert Zeiser Prof. Dr. Michael Bock Prof. Dominik von Elverfeldt Prof. Dr. Maxim Zaitsev Dr. Sergey Korchak Dr. Stefan Glöggler Prof. Dr. Jan-Bernd Hövener Prof. Dr. Eduard Y. Chekmenev Prof. Dr. Franz Schilling Dr. Stephan Knecht Dr. Andreas B. Schmidt 《Angewandte Chemie (International ed. in English)》2023,62(36):e202306654
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Rebecca Wiesner Christin Scheller Finja Krebs Hermann Wätzig Imke Oltmann-Norden 《Electrophoresis》2021,42(3):206-218
The development of capillary electrophoresis, especially CE-SDS devices, has led CE-SDS to become an established tool in a wide range of applications in the analysis of biopharmaceuticals and is increasingly replacing its method of origin, SDS-PAGE. The goal of this study was to evaluate the comparability of molecular weight (MW) determination especially by CE-SDS and SDS-PAGE. For ensuring comparability, model proteins that have little or no posttranslational modifications and an IgG antibody were used. Only a minor influence of sample preparation conditions, including sample buffer, temperature conditions, and different reducing agents on the MW determination were found. In contrast, the selection of the MW marker plays a decisive role in determining the accurate apparent MW of a protein. When using different MW markers, the deviation in MW determination can exceed 10%. Interestingly, CE-SDS and 10% SDS-PAGE hardly differ in their trueness of MW determination. The trueness in relation to the reference MW for each protein was calculated. Although the trueness values for the model proteins considered range between 1.00 and 1.11 using CE-SDS, they range between 0.93 and 1.03 on SDS-PAGE, depending on the experimental conditions chosen. 相似文献
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Dr. Selina Beatrice van der Meer Theresa Seiler Christin Buchmann Georgia Partalidou Dr. Sophia Boden Dr. Kateryna Loza Dr. Marc Heggen Dr. Jürgen Linders Dr. Oleg Prymak Prof. Dr. Cristiano L. P. Oliveira Prof. Dr. Laura Hartmann Prof. Dr. Matthias Epple 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(4):1451-1464
Ultrasmall gold nanoparticles (diameter about 2 nm) were surface-functionalized with cysteine-carrying precision macromolecules. These consisted of sequence-defined oligo(amidoamine)s (OAAs) with either two or six cysteine molecules for binding to the gold surface and either with or without a PEG chain (3400 Da). They were characterized by 1H NMR spectroscopy, 1H NMR diffusion-ordered spectroscopy (DOSY), small-angle X-ray scattering (SAXS), and high-resolution transmission electron microscopy. The number of precision macromolecules per nanoparticle was determined after fluorescent labeling by UV spectroscopy and also by quantitative 1H NMR spectroscopy. Each nanoparticle carried between 40 and 100 OAA ligands, depending on the number of cysteine units per OAA. The footprint of each ligand was about 0.074 nm2 per cysteine molecule. OAAs are well suited to stabilize ultrasmall gold nanoparticles by selective surface conjugation and can be used to selectively cover their surface. The presence of the PEG chain considerably increased the hydrodynamic diameter of both dissolved macromolecules and macromolecule-conjugated gold nanoparticles. 相似文献
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Methane as a Selectivity Booster in the Arc‐Discharge Synthesis of Endohedral Fullerenes: Selective Synthesis of the Single‐Molecule Magnet Dy2TiC@C80 and Its Congener Dy2TiC2@C80 下载免费PDF全文
Katrin Junghans Christin Schlesier Aram Kostanyan Nataliya A. Samoylova Qingming Deng Marco Rosenkranz Sandra Schiemenz Dr. Rasmus Westerström Prof. Dr. Thomas Greber Prof. Dr. Bernd Büchner Dr. Alexey A. Popov 《Angewandte Chemie (International ed. in English)》2015,54(45):13411-13415
The use of methane as a reactive gas dramatically increases the selectivity of the arc‐discharge synthesis of M‐Ti‐carbide clusterfullerenes (M=Y, Nd, Gd, Dy, Er, Lu). Optimization of the process parameters allows the synthesis of Dy2TiC@C80‐I and its facile isolation in a single chromatographic step. A new type of cluster with an endohedral acetylide unit, M2TiC2@C80, is discovered along with the second isomer of M2TiC@C80. Dy2TiC@C80‐(I,II) and Dy2TiC2@C80‐I are shown to be single‐molecule magnets (SMM), but the presence of the second carbon atom in the cluster Dy2TiC2@C80 leads to substantially poorer SMM properties. 相似文献
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This Note presents an experimental vibro-acoustic set-up that aims to reproduce the energy pumping phenomenon between an acoustic medium and an essentially nonlinear oscillator. It shows a one-way irreversible transfer of energy between the first acoustic mode in a tube and a thin visco-elastic membrane. To cite this article: B. Cochelin et al., C. R. Mecanique 334 (2006). 相似文献
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