A5058698203- Magnetic confinement fusion research
- Molecular spectroscopy and chirality
- Solar and Space Plasma Dynamics
- Particle accelerators and beam dynamics
- Analytical Chemistry and Chromatography
- Metabolomics and Mass Spectrometry Studies
- Astronomical Observations and Instrumentation
- Ionosphere and magnetosphere dynamics
- Stellar, planetary, and galactic studies
- NMR spectroscopy and applications
- Plasma Diagnostics and Applications
- Various Chemistry Research Topics
- Computational Drug Discovery Methods
- Gamma-ray bursts and supernovae
- Advanced NMR Techniques and Applications
- Atomic and Molecular Physics
- Superconducting Materials and Applications
- Astronomy and Astrophysical Research
- Synthesis and biological activity
- Fusion materials and technologies
- Astro and Planetary Science
- Nuclear Physics and Applications
- Click Chemistry and Applications
- Microbial Natural Products and Biosynthesis
- Protein Structure and Dynamics
Fundação Oswaldo Cruz
2008-2024
Faculdades Oswaldo Cruz
2022
Max Planck Institute for Biophysical Chemistry
2000-2008
University of Washington
2007
University of California, San Diego
2007
Max Planck Institute for Plasma Physics
1987-2003
Max Planck Society
1988-2003
Goethe University Frankfurt
1997-2002
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung
2002
Yale University
2001
The first plasma experiments on the W7AS advanced stellarator were conducted in October 1988, after magnetic surface mapping. characteristics of device are described. During phase operation, 70 GHz ECF was used to generate and heat a 'currentless' which maintained quasi-steady state for typically 0.5 s. Effects configuration confinement measures deal with observed current (bootstrap ECF-driven current) investigated. Preliminary results transport analysis presented compared predictions models.
Sagittamide A is a long-chain acyclic α,ω-dicarboxylic acid with eight stereocenters. The central hexahydroxyhexane moiety carries six of them. For this moiety, two different relative stereochemical assignments were published in 2006. In communication, one configuration clearly singled out based on NOEs, J- and residual dipolar couplings despite conformational averaging that present moiety. proposed NMR method relies the measurement recently introduced alignment media are compatible organic...
The structure of the water-soluble, periplasmic domain fumarate sensor DcuS (DcuS-pd) has been determined by NMR spectroscopy in solution. is a prototype for sensory histidine kinase with transmembrane signal transfer. belongs to CitA family sensors that are specific sensing di- and tricarboxylates. folded autonomously shows helices at N C terminus, suggesting direct linking or connection two regions. constitutes novel fold. nearest structural neighbor Per-Arnt-Sim photoactive yellow protein...
A new method based on NMR spectroscopy is introduced to determine the absolute configuration of natural compounds and has been successfully applied sucro-neolambertellin. The relies measurement residual dipolar couplings (RDCs), which allow unknown stereocenters be related with known (see picture). approach used D-threo-2,5-hexodiulofuranose moiety by relating it α-D-glucose.
Vanillin is the main component of natural vanilla extract and responsible for its flavoring properties. Besides well-known applications as an additive in food cosmetics, it has also been reported that vanillin can inhibit fungi clinical interest, such Candida spp., Cryptococcus Aspergillus well dermatophytes. Thus, present work approaches synthesis a series derivatives with 1,2,3-triazole fragments evaluation their antifungal activities against albicans, glabrata, parapsilosis, tropicalis,...
Abstract The nuclear magnetic resonance extracted data (NMReDATA) format has been proposed as a way to store, exchange, and disseminate (NMR) physical chemical metadata of compounds. In this paper, we report on analytical workflows that take advantage the uniform standardized NMReDATA format. We also give access repository sample data, which can serve for validating software packages encode or decode files in
A short synthesis of EDTA-based metal chelates that can be attached to the cysteine residue a protein via disulfide bond is described. The complexes were used after coordination lanthanides align trigger factor and apo-calmodulin in solution yield residual dipolar couplings pseudocontact shifts. Alignment tensors for new tags are linearly independent compared those previously published tags.
Both in Ohmically and beam-heated L-mode discharges of ASDEX, the electron-temperature (Te) profile shape can be varied over a wide range by choice safety factor qa. The power-deposition profile, on contrary, has no effect Te shape. In current-free W-VII-A stellarator plasmas, such invariance property is found. An independent constraint seems to fix current distribution j(r) tokamak, which defines conditions electron heat transport.Received 4 February...
A series of 19 novel eugenol derivatives containing a 1,2,3-triazole moiety was synthesized via two-step process, with the key step being copper(I)-catalyzed azide–alkyne cycloaddition reaction. The compounds were assessed for their antifungal activities against Colletotrichum gloeosporioides, causative agent papaya anthracnose. Triazoles 2k, 2m, 2l, and 2n, at 100 ppm, most effective, reducing mycelial growth by 88.3, 85.5, 82.4, 81.4%, respectively. Molecular docking calculations allowed...
Plasma build-up and heating of net-current-free plasmas in W VII-A was investigated by ECRH. Experiments were performed at two ECR-frequencies (28 70 GHz) different scenarios such as first harmonic ordinary mode second extraordinary heating. The basic effects predicted theory, i.e. localized wave absorption optical thickness the plasma verified. electron heat conduction found to be governed neoclassical losses core for high enough temperatures, whereas enhanced have assumed outer regions....
Eine neue NMR-spektroskopische Methode wird eingeführt, die Bestimmung der absoluten Konfiguration von Naturstoffen ermöglicht und erfolgreich auf Sucro-Neolambertellin angewendet wurde. Die beruht Messung dipolaren Restkopplungen (RDCs), wodurch es gelingt, Konfigurationen unbekannter Stereozentren mit bekannten in Beziehung zu setzen (siehe Bild). Der Ansatz verwendet, um des D-threo-2,5-Hexodiulofuranoserings bestimmen.
The 1H,15N-HMBC experiment is a very useful tool for the structure determination of alkaloids. In conjunction with computer program Cocon, we show how 1H,15N-HMBC-derived connectivity information can assist in assignment constitution, by greatly reducing number possible structures compatible given data set. method illustrated marine natural products oroidin (1) and manzacidin A (2).
The structure of a catalytic intermediate with important implications for the interpretation stereochemical outcome palladium complex catalyzed allylic substitution phosphino–oxazoline (PHOX) ligands is determined by liquid state NMR. displays novel that highly distorted compared other η2-olefin complexes known so far. has been from nuclear overhauser data (NOE), scalar coupling constants, and long range projection angle restraints derived dipole cross-correlated relaxation multiple quantum...
WENDELSTEIN VII-A has been operated for ten years. It is a low-shear, high-aspect-ratio device. The confinement properties have thoroughly studied both ohmically heated and net-current free plasmas. For the latter case, NBI- ECF-maintained plasmas were of particular importance. was found that under optimized conditions core high-pressure, mainly governed by collisional effects.
The computer-assisted constitutional assignment of ascomycin (1) is discussed. This example demonstrates that the NMR-based structure generator Cocon able to analyze data sets organic molecules covering full known range in size and complexity. structural proposals were validated by calculating 13C NMR chemical shifts using computer program SpecEdit. enhanced calculation time achieved preorganizing input also demonstrated for aflatoxin B1 (2), 11-hydroxyrotenone (3), haemoventosin (4).
The 2D NMR-guided computer program COCON can be extremely valuable for the constitutional analysis of unknown compounds, if its results are evaluated by neural network-assisted 13C NMR chemical shift and substructure analyses. As instructive examples, data sets four differently complex marine natural products were thoroughly investigated. a significant step towards true automated structure elucidation, it is shown that primary output safely diminished to less than 1% original size without...
The Third International Symposium on Toroidal Plasma Confinement was held at the Max-Planck-Institut für Plasmaphysik Garching near Munich in Federal Republic of Germany from 26 to 30 March 1973. This Symposium, which sponsored by European Physical Society, third a series, first Princeton 1966 and second Dubna 1969.
The endophytic fungus Mycosphaerella sp. (UFMGCB2032) was isolated from the healthy leaves of Eugenia bimarginata, a plant Brazilian savanna. Two novel usnic acid derivatives, mycousfuranine (1) and mycousnicdiol (2), were ethyl acetate extract, their structure elucidated by NMR MS analyses. Compounds 1 2 exhibited moderate antifungal activities against Cryptococcus neoformans gattii, each with minimum inhibitory concentration values 50.0 μg/mL 250.0 μg/mL, respectively.
The constitutional assignment of natural products by NMR spectroscopy is usually based on 2D experiments like COSY, HSQC, and HMBC. actual difficulty the structure elucidation problem depends more type investigated molecule than its size. moment HMBC data involved in process or a large number heteroatoms present, possibility multiple solutions fitting same set exists. A software can be used to find such alternative assignments help discussion order correct solution. But this rarely done....