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31.
A series of 2,2‐dimethyl‐5‐(5′‐R‐hetarylidene)‐1,3‐dioxane‐4,6‐diones has been synthesized for examing a structure–activity relationship. Furyl and thienyl derivatives of Meldrum's acid possess neurotropic activity comprising both depriming and activating components. Comparison of acute toxicity of carbon, silicon and germanium analogues in the furan series of the compounds has demonstrated that the germanium derivative is 11.5 times less toxic than the carbon analogue and four times less toxic than the silicon derivative. 2,2‐Dimethyl‐5‐(5′‐triethylsilyl‐2′‐thenylidene)‐1,3‐dioxane‐4,6‐dione has moderate toxicity with the highest neurotropic and cytotoxic activity Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
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Albela B Carina R Policar C Poussereau S Cano J Guilhem J Tchertanov L Blondin G Delroisse M Girerd JJ 《Inorganic chemistry》2005,44(20):6959-6966
Two manganese complexes, (py2(NMe)2)MnIICl2 (1) and [(py2(NMe)2)MnIIIF2]+ (2), are here described with the macrocyclic ligand py2(NMe)2 (py2(NMe)2 = N,N'-dimethyl-2,11-diaza[3,3](2,6)pyridinophane). For both, the crystal structure is reported. The UV-visible spectrum of 2 exhibits a very broad near-infrared (NIR) band corresponding to the transition between the two e(g)-type orbitals split by the Jahn-Teller effect. A negative D value of ca. -4 cm(-1) was estimated by high-field and high-frequency electron paramagnetic resonance (HF-EPR) spectroscopy, which was consistent with symmetry considerations. Density functional theory (DFT) calculations on 2 support the 5B1 electronic ground state predicted from the X-ray structure. Moreover, to explain the large value of the D parameter, a spin triplet first excited spin state was postulated to occur at low energy. This was confirmed by the DFT calculations. 相似文献
33.
Shabnam Luba Faisal Shaikh N. Martucci Alessandro Gomes Vincent G. 《Journal of Solid State Electrochemistry》2020,24(1):45-56
Journal of Solid State Electrochemistry - A non-enzymatic sensor was developed for simultaneous detection of glucose, ethanol, and glycerol concentrations in wine using nickel nanoparticles on... 相似文献
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Kathrin Siegl Dr. Luba Kolik-Shmuel Dr. Mingming Zhang Dr. Sylvain Prévost Dr. Kalanit Vishnia Prof. Amram Mor Dr. Marie-Sousai Appavou Dr. Charl J. Jafta Prof. Dganit Danino Prof. Dr. Michael Gradzielski 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(23):6904-6910
Monodisperse unilamellar nanotubes (NTs) and nanoribbons (NRs) were transformed to multilamellar NRs and NTs in a well-defined fashion. This was done by using a step-wise approach in which self-assembled cationic amino acid amphiphile (AAA) formed the initial NTs or NRs, and added polyanion produced an intermediate coating. Successive addition of cationic AAA formed a covering AAA layer, and by repeating this layer-by-layer (LBL) procedure, multi-walled nanotubes (mwNTs) and nanoribbons were formed. This process was structurally investigated by combining small-angle neutron scattering (SANS) and cryogenic-transmission electron microscopy (cryo-TEM), confirming the multilamellar structure and the precise layer spacing. In this way the controlled formation of multi-walled suprastructures was demonstrated in a simple and reproducible fashion, which allowed to control the charge on the surface of these 1D aggregates. This pathway to 1D colloidal materials is interesting for applications in life science and creating well-defined building blocks in nanotechnology. 相似文献
35.
The germanium atom is penta‐coordinated and adopts trigonal bipyramidal geometry. The 2‐benzo[b]thienyl group and the nitrogen atom each occupy an apical position with the transannular N → Ge bond distance being 2.180(4) Å. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
36.
Edmunds Lukevics Luba Ignatovich Ilze Sleiksha Irina Shestakova Ilona Domrachova Jury Popelis 《应用有机金属化学》2005,19(10):1109-1113
A series of 5‐[1‐methylsilacyclo‐pentyl/‐hexyl]‐2‐furfural, 5‐[1‐methylsilacyclo‐pentyl/‐hexyl]‐2‐thiophene carbaldehyde and 1,1‐bis(5‐formyl‐2‐furyl)silacyclo‐pentane/‐hexane and their thiosemicarbazones has been synthesized and subjected to antitumour assay. The effects of the substituents and the heterocycle were examined to establish structure–activity relationships. Thiosemicarbazones of 5‐(1‐methylsilacyclohexyl)furfural and 5‐(1‐methylsilacyclopentyl)furfural were very active (1.0–4.0 µg ml?1) in vitro against human fibrosarcoma HT‐1080 and mouse hepatoma MG‐22A cells. At the same time, they were less toxic for normal fibroblasts 3T3. All compounds synthesized exhibited low or moderate toxicity (LD50 152–1904 mg kg?1). Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
37.
Tomasz ?ojewski Pawe? Mi?kowiec Marcin Molenda Anna Lubańska Joanna ?ojewska 《Applied Physics A: Materials Science & Processing》2010,98(3):625-633
The cellulose–water system was traced down by the in situ transmission FTIR spectroscopy upon water desorption/sorption cycles
at various conditions (dry air, humid air, water vapour) and temperatures. The results provide the information on the changes
of the hydrogen bonds network during water desorption from paper and the changes in water sorption capacity of paper in the
cycles. 相似文献
38.
The paper gives a historical perspective of forensic DNA analysis and overviews existing technologies implemented in forensic laboratories for DNA profiling. Short tandem repeat analysis, mitochondrial DNA and Y-chromosome analysis are described. The review also focuses on emerging new technologies, which represent an interest for the DNA forensic community. Short tandem repeat analysis, by microelectronic chip device, electrophoretic microdevice and matrix assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry are reviewed in this context. 相似文献
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Experimental observations of the effect of homogeneous longitudinal magnetic fleld on the propagation of spontaneously existing s variety of ionization waves and subharmonic wave in neon d.c. discharge are reported. The measurements were realized in a part of positive column where the motion of the waves is coherent and wave interactions can be neglected. Changes in wave amplitudes are explained in terms of parameters of Landau amplitude equation and their dependence of the magnetic field. 相似文献