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The alkaloid 4-O-methylsinomenine was modified by introducing pyrimidine substituents at the C-1 position of the backbone. Two methods were used to synthesize these hybrid molecules. The first method involves the preparation of 1-ethynyl-4-O-methylsinomenine and a sequence of cross-coupling reactions with benzoic acid chlorides and cyclocondensation with amidines. The second method is based on palladium-catalyzed carbonylation–cross coupling of 1-iodo-4-O-methylsinomenine with phenylacetylene in the presence of Mo(CO)6 as a source of CO in MeCN and subsequent cyclocondensation of alkynyl ketone with amidines. The carbonylation–crosscoupling reaction proceeded selectively in the presence of the PdCl2/(1-Ad)2PBn catalytic system.

Three main paths have been selected within the ELI Beamlines research program for transforming driving laser pulses into brilliant beams of short wavelength radiation: High-order harmonic generation in gases, Plasma X-ray sources, and sources based on relativistic electron beams accelerated in laser-plasma. For each of these research areas, dedicated beamlines are built to provide a unique combination of X-ray sources to the user community. The employment of these beamlines has a well-defined balance between fundamental science and applications in different fields of science and technology. Besides those beamlines, a plasma betatron radiation source driven by the PW-class HAPLS laser system is being commissioned in the plasma physics platform to serve as a unique diagnostic tool for dense plasma and warm dense matter probing.

We report on development of laser-driven X-ray sources at ELI Beamlines. Those include an XUV beamline based on high-order harmonic generation in gas, sources based on relativistic electrons accelerated by laser and plasma X-ray sources.

We present experimental setup for user-oriented high-harmonic source with a description of different focusing and interaction geometries. Infrared rejection system and resulting extreme ultraviolet beam characterization are also described. Beamline is designed to be driven with 100 mJ

Modification of the steroidal alkaloid solasodine was performed by introduction of 1,2,3-triazolyl substituents at the С-6 atom of spirosolane ring system. The azidolysis of 5,6α-epoxysolasodine diacetate, formed as the major product during epoxidation of solasodine diacetate by the action of sodium azide in DMF in the presence of ammonium chloride, proceeded through the formation of 6β-azido-5α-hydroxysolasodine diacetate. The newly obtained azide was used in reactions with terminal alkynes in the presence of copper(I) bromide and N,N-diisopropylethylamine in DMF to synthesize the respective (22R,25R)-N,O-diacetyl-6β-[4-aryl-1,2,3-triazol-1-yl]-5α-hydroxyspirosolanes.

International audience; We present experimental results obtained at a user-oriented XUV beamline implemented at the ELI Beamlines facility. The coherent XUV radiation is produced via high harmonic generation in gases in a loose focusing geometry. The heamline is designed to be driven by 1 kHz, 100 mJ, 20 Is pulses centered at a wavelength of 830 nm. Results such as XUV spectra, beam wavefront and pulse energy obtained during the heamline commissioning with a commercial 1 kHz, 5 mJ, 40 fs laser system are presented. A unique XUV spectrometer for source characterization designed to reach a very high sensitivity is described in detail, and we demonstrate a novel technique for single shot and every shot. XUV pulse energy measurement. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement.

The low conversion efficiency of high-order harmonic generation (HHG) in gases is an insurmountable limitation for many applications, where a considerable photon flux is an instrumental prerequisite. We present a study of the HHG conversion efficiency dependence on the driving laser intensity and analyze the conditions for optimal phase-matching in a loose focusing configuration and long generation medium using a Ti:Sapphire laser. Moreover, by determination of the influence of plasma effects on the driving laser pulse, we observe a correlation between the HHG conversion efficiency and the blueshift of the fundamental pulse. The maximal HHG conversion efficiency is achieved just before the driving laser spectrum is considerably affected by the plasma. Similar behavior is observed in HHG for different noble gases. In this respect, the appearance of a plasma-induced spectral shift in the driving laser might serve as an indication of a substantial loss of HHG conversion efficiency. Consequently, our findings can be exploited to obtain essential information about the laser-plasma interaction process during HHG and can pave the way for a more convenient control of optimal HHG conditions.

Tests of electromagnetic susceptibility (EMS) are part of the type of approval procedure for sound level meters in the field of legal metrology. Starting in January 1996 every electronic device on the European market has to have a label that indicates a certification of the device, which also includes requirements on electromagnetic susceptibility. The EMS test of sound level meters at the Physikalisch‐Technische Bundesanstalt (PTB) are performed in a radio frequency anechoic chamber. The electric field strength is 6 V/m, the frequency range is 26–1000 MHz. The frequency is varied in steps of 4% and the signal is modulated with 1000 Hz (m=80%). An acoustical signal is applied to the sound level meter and the difference of the displayed levels with and without the electromagnetic field has to be within specified tolerances (0.5 to 2 dB). At the moment not all types of sound level meters comply with these tolerances; with instruments under test deviations up to 18 dB had been observed. The present test proc...

The Deutsche Forschung sqemenschaft and study of airport noise is reviewed, some further results are included. The study, which considered sociological, psychological and physiological impacts, also describes statistical and analytical methods.

One key parameter in the high-order harmonic generation (HHG) phenomenon is the exact frequency of the generated harmonic field. Its deviation from perfect harmonics of the laser frequency can be explained considering (i) the single-atom laser-matter interaction and (ii) the spectral changes of the driving laser. In this work, we perform an experimental and theoretical study of the causes that generate spectral changes in the HHG radiation. We measured the driving laser spectral shift after high harmonic generation in long medium using a correction factor to take into account the multiple possible HHG initiation distances along the laser path. We separate out the contribution of laser spectral shift from the resultant high harmonic spectral shift in order to elucidate the microscopic effect of spectral shift in HHG. Therefore, in some cases we are able to identify the dominant electron trajectory from the experimental data. Our investigations lead to valuable conclusions about atomic dipole phase contribution to a high harmonic spectral shift. We demonstrate that the significant contribution of a long electron path leads to a high harmonic shift, which differs from that expected from the driving laser. Moreover, we assess the origin of the high-order harmonics spectral broadening and provide an explanation for the narrowest high harmonic spectral width in our experiment., Comment: 24 pages, 6 figures