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991.
Luigi Ornano Yuri Donno Cinzia Sanna Mauro Ballero Armandodoriano Bianco 《Natural product research》2016,30(8):920-925
Artemisia caerulescens subsp. densiflora Viv. is a rare endemic species from Corsica and Sardinia. We studied a sample collected from Razzoli, an island of the La Maddalena Archipelago. The polar secondary metabolites content of this species was investigated for the first time in this study showing the presence of sesquiterpenoids, flavonoids, caffeoylquinic acids and a coumarin, with the presence of several compounds already recognised in this genus. The metabolites composition was analysed in two different phenological stages, post blooming and flowering. During the blooming stage, the plant showed a molecular pattern mainly represented by sesquiterpenes and sterols with a minor amount of phenolics, while in flowering stage the molecular pattern was more rich in flavonoids and phenylpropanoids. 相似文献
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Fabian Allmendinger Peter Blümler Michael Doll Olivier Grasdijk Werner Heil Klaus Jungmann Sergej Karpuk Hans-Joachim Krause Andreas Offenhäusser Maricel Repetto Ulrich Schmidt Yuri Sobolev Kathlynne Tullney Lorenz Willmann Stefan Zimmer 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2017,71(4):98
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A two-day workshop on “X-ray Echo Spectroscopy: Opportunities and Feasibility” was held at the Advanced Photon Source (APS), Argonne National Laboratory, USA, September 9–10, 2016, attracting 42 attendees. The focus of the workshop was to explore the scientific potential and technical feasibility of the recently proposed X-ray echo spectroscopy and to discuss a path for its R&D and realization. 相似文献
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Bernd Wrackmeyer Elena V. Klimkina Yuri N. Bubnov 《Journal of organometallic chemistry》2001,620(1-2):51-59
The reaction of 1-boraadamantane 1 with 1-alkynyltin (3), -germanium (4), and -silicon compounds (5) leads to enlargement of the tricyclic system by formation of 4-methylene-3-borahomoadamantanes (6–9). These are 1,1-organoboration reactions which proceed by cleavage of the M---C bond (M=Sn, Ge, Si). There is evidence for 1,1-deorganoboration which apparently take place much more readily than for non-cyclic analogues, most likely as the result of the strained tricyclic system. When 2-ethyl-1-boraadamantane (2) is used, again 3-borahomoadamantanes are formed, the isomers 15–18. The product distribution is sensitive to steric effects. However, it appears that the B---C(H)Et bond in 2 is slightly more reactive than the B---CH2 bonds. All products were characterised by 1H-, 11B-, 13C-, 29Si- and 119Sn-NMR. 相似文献
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