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Joseph A. Giesen Benjamin J. Diament Scott M. Grayson 《Journal of the American Society for Mass Spectrometry》2018,29(3):490-500
Calibrants based on synthetic dendrimers have been recently proposed as a versatile alternative to peptides and proteins for both MALDI and ESI mass spectrometry calibration. Because of their modular synthetic platform, dendrimer calibrants are particularly amenable to tailoring for specific applications. Utilizing this versatility, a set of dendrimers has been designed as an internal calibrant with a tailored mass defect to differentiate them from the majority of natural peptide analytes. This was achieved by incorporating a tris-iodinated aromatic core as an initiator for the dendrimer synthesis, thereby affording multiple calibration points (m/z range 600–2300) with an optimized mass-defect offset relative to all peptides composed of the 20 most common proteinogenic amino acids. 相似文献
124.
Dr. Benjamin A. Chalmers Hui Xing Sevan Houston Dr. Charlotte Clark Dr. Sussan Ghassabian Dr. Andy Kuo Benjamin Cao Andrea Reitsma Cody‐Ellen P. Murray Dr. Jeanette E. Stok Dr. Glen M. Boyle Carly J. Pierce Stuart W. Littler Prof. David A. Winkler Prof. Paul V. Bernhardt Dr. Cielo Pasay Prof. James J. De Voss Prof. James McCarthy Prof. Peter G. Parsons Prof. Gimme H. Walter Prof. Maree T. Smith Prof. Helen M. Cooper Prof. Susan K. Nilsson Dr. John Tsanaktsidis Dr. G. Paul Savage Prof. Craig M. Williams 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2018,130(28):8491-8491
125.
Viktor Reshetnikov Steffen Daum Dr. Christina Janko Weronika Karawacka Dr. Rainer Tietze Prof. Dr. Christoph Alexiou Dr. Solomiya Paryzhak Dr. Tetiana Dumych Prof. Dr. Rostyslav Bilyy Dr. Philipp Tripal Dr. Benjamin Schmid Dr. Ralf Palmisano Prof. Dr. Andriy Mokhir 《Angewandte Chemie (International ed. in English)》2018,57(37):11943-11946
Mitochondrial membrane potential is more negative in cancer cells than in normal cells, allowing cancer targeting by delocalized lipophilic cations (DLCs). However, as the difference is rather small, these drugs affect also normal cells. Now a concept of pro‐DLCs is proposed based on an N‐alkylaminoferrocene structure. These prodrugs are activated by the reaction with reactive oxygen species (ROS) forming ferrocenium‐based DLCs. Since ROS are overproduced in cancer, the high‐efficiency cancer‐cell‐specific targeting of mitochondria could be achieved as demonstrated by fluorescence microscopy in combination with two fluorogenic pro‐DLCs in vitro and in vivo. We prepared a conjugate of another pro‐DLC with a clinically approved drug carboplatin and confirmed that its accumulation in mitochondria was higher than that of the free drug. This was reflected in the substantially higher anticancer effect of the conjugate. 相似文献
126.
Surprising Antibacterial Activity and Selectivity of Hydrophilic Polyphosphoniums Featuring Sugar and Hydroxy Substituents 下载免费PDF全文
Tyler J. Cuthbert Benjamin Hisey Tristan D. Harrison Dr. John F. Trant Prof. Elizabeth R. Gillies Prof. Paul J. Ragogna 《Angewandte Chemie (International ed. in English)》2018,57(39):12707-12710
There is currently an urgent need for the development of new antibacterial agents to combat the spread of antibiotic‐resistant bacteria. We explored the synthesis and antibacterial activities of novel, sugar‐functionalized phosphonium polymers. While these compounds exhibited antibacterial activity, we unexpectedly found that the control polymer poly(tris(hydroxypropyl)vinylbenzylphosphonium chloride) showed very high activity against both Gram‐negative Escherichia coli and Gram‐positive Staphylococcus aureus and very low haemolytic activity against red blood cells. These results challenge the conventional wisdom in the field that lipophilic alkyl substituents are required for high antibacterial activity and opens prospects for new classes of antibacterial polymers. 相似文献
127.
Natural products from the human microbiota may mediate host health and disease. However, discovery of the biosynthetic gene clusters that generate these metabolites has far outpaced identification of the molecules themselves. Here, we used an isolation-independent approach to access the probable products of a nonribosomal peptide synthetase-encoding gene cluster from Ruminococcus bromii, an abundant gut commensal bacterium. By combining bioinformatics with in vitro biochemical characterization of biosynthetic enzymes, we predicted that this pathway likely generates an N-acylated dipeptide aldehyde (ruminopeptin). We then used chemical synthesis to access putative ruminopeptin scaffolds. Several of these compounds inhibited Staphylococcus aureus endoproteinase GluC (SspA/V8 protease). Homologs of this protease are found in gut commensals and opportunistic pathogens as well as human gut metagenomes. Overall, this work reveals the utility of isolation-independent approaches for rapidly accessing bioactive compounds and highlights a potential role for gut microbial natural products in targeting gut microbial proteases. 相似文献
128.
M. Sc. Benjamin Scheibe Clemens Pietzonka M. Sc. Otto Mustonen Prof. Dr. Maarit Karppinen Prof. Dr. Antti J. Karttunen Prof. Dr. Mihail Atanasov Prof. Dr. Frank Neese Dr. Matthias Conrad Prof. Dr. Florian Kraus 《Angewandte Chemie (International ed. in English)》2018,57(11):2914-2918
The D2h‐symmetric dinuclear complex anion [U2F12]2? of pastel green Sr[U2F12] shows a hitherto unknown structural feature: The coordination polyhedra around the U atoms are edge‐linked monocapped trigonal prisms, the UV atoms are therefore seven‐coordinated. This leads to a U–U distance of 3.8913(6) Å. A weak UV–UV interaction is observed for the dinuclear [U2F12]2? complex and described by the antiferromagnetic exchange Jexp of circa ?29.9 cm?1. The crystalline compound can be easily prepared from SrF2 and β‐UF5 in anhydrous hydrogen fluoride (aHF) at room temperature. It was studied by means of single crystal X‐ray diffraction, IR, Raman and UV/VIS spectroscopy, magnetic measurements, and by molecular as well as by solid‐state quantum chemical calculations. 相似文献
129.
Direct Access to Aryl Bis(trifluoromethyl)carbinols from Aryl Bromides or Fluorosulfates: Palladium‐Catalyzed Carbonylation 下载免费PDF全文
Katrine Domino Cedrick Veryser Benjamin A. Wahlqvist Cecilie Gaardbo Dr. Karoline T. Neumann Prof.Dr. Kim Daasbjerg Prof. Dr. Wim M. De Borggraeve Prof. Dr. Troels Skrydstrup 《Angewandte Chemie (International ed. in English)》2018,57(23):6858-6862
A palladium‐catalyzed carbonylative approach for the direct conversion of (hetero)aryl bromides into their α,α‐bis(trifluoromethyl)carbinols is described, and it employs only stoichiometric amounts of carbon monoxide and trifluoromethyltrimethylsilane. In addition, aryl fluorosulfates proved highly compatible with these reaction conditions. The method is tolerant of a diverse set of functional groups, and it is adaptable to late‐stage carbon‐isotope labeling. 相似文献
130.
Li Fang Benjamin L. Davis Haiyan Lu John R. Lombardi 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2001,57(14)
In an excitation range of 620–760 nm, resonance Raman spectra of aluminum dimers (Al2) in an argon matrix have been obtained for the first time. Temperature annealing experiments were performed to remove Raman lines attributed site effects caused by the Al2/Ar matrix. We observe a single fundamental at 293.3 (5) cm−1 along with a progression up to 1149 (1) cm−1. Taking successive differences of band centers we obtain spectroscopic constants for the ground state fundamental, ωe=297.5 (5) cm−1, the anharmonicity, ωexe=1.68 (8) cm−1. Our results are in close agreement with previous experimental results for Al2 which designate the ground state as a 3Πu state, and may be considered as confirmation of this assignment. 相似文献