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Dr. Marcel Sickert Dr. Harald Weinstabl Brendan Peters Xiao Hou Prof. Dr. Mark Lautens 《Angewandte Chemie (International ed. in English)》2014,53(20):5147-5151
A palladium‐catalyzed intermolecular cross‐coupling of two aryl iodides is reported, giving polycyclic ring systems with a high level of convergence and efficiency. 相似文献
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Dr. Alexey S. Kiryutin Dr. Grit Sauer Dr. Daniel Tietze Martin Brodrecht Stephan Knecht Prof. Dr. Alexandra V. Yurkovskaya Prof. Dr. Konstantin L. Ivanov Dr. Olga Avrutina Prof. Dr. Harald Kolmar Prof. Dr. Gerd Buntkowsky 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(16):4025-4030
Two-dimensional NMR spectroscopy is one of the most important spectroscopic tools for the investigation of biological macromolecules. However, due to the low sensitivity of NMR spectroscopy, it takes usually from several minutes to many hours to record such spectra. Here, the possibility of detecting a bioactive derivative of the sunflower trypsin inhibitor-1 (SFTI-1), a tetradecapeptide, by combining parahydrogen-induced polarization (PHIP) and ultrafast 2D NMR spectroscopy is shown. The PHIP activity of the inhibitor was achieved by labeling with O-propargyl-l -tyrosine. In 1D PHIP experiments a signal enhancement of a factor of approximately 1200 compared to standard NMR was found. This enhancement permits measurement of 2D NMR correlation spectra of low-concentrated SFTI-1 in less than 10 seconds, employing ultrafast single-scan 2D NMR detection. As experimental examples PHIP-assisted ultrafast single-scan TOCSY spectra of SFTI-1 are shown. 相似文献
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Harald Pühringer Zeineb Nejim Michael Pfleger Stefan Katletz 《Journal of Infrared, Millimeter and Terahertz Waves》2016,37(2):123-127
A novel and continuous detection scheme for the pulse amplitude and temporal position of a terahertz time domain system is presented. Currently, we have achieved a sampling time of 25 Hz and a resolution of less than 70 fs. The method is therefore very well suited for online measurements in production processes to monitor the thickness and inhomogeneities in the composition of non-conducting materials. 相似文献
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Benjamin Radel Edme H. Hardy Zorana Djuric Markus Mahlbacher Michael Haist Harald S. Müller 《Magnetic resonance in chemistry : MRC》2019,57(10):836-844
Not only in low-field nuclear magnetic resonance, Laplace inversion is a relevant and challenging topic. Considerable conceptual and technical progress has been made, especially for the inversion of data encoding two decay dimensions. Distortion of spectra by overfitting of even moderate noise is counteracted requiring a priori smooth spectra. In this contribution, we treat the case of simple and fast one-dimensional decay experiments that are repeated many times in a series in order to study the evolution of a sample or process. Incorporating the a priori knowledge that also in the series dimension evolution should be smooth, peak position can be stabilized and resolution improved in the decay dimension. It is explained how the standard one-dimensional regularized Laplace inversion can be extended quite simply in order to include regularization in the series dimension. Obvious improvements compared with series of one-dimensional inversions are presented for simulated as well as experimental data. For the latter, comparison with multiexponential fitting is performed. 相似文献
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Harald Gröger Jens R. Goerlich Reinhard Schmutzler Jürgen Martens 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):253-259
Abstract The synthesis of a cyclic α-amino phosphine oxide and sulfide with an incorporated benzo-thiazine moiety is described. The products can be regarded as analogues of the biologically active thiazolidinylphosphonates, in which several characteristic functional groups have been modified. 相似文献
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