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221.
Sabine Ruf Gerd Neudert Susanne Gürtler Renate Grünert Patrick J. Bednarski Hans-Hartwig Otto 《Monatshefte für Chemie / Chemical Monthly》2008,139(7):847-857
A number of 1,4-diaryl-3-methylene substituted β-lactams, the addition products obtained from their reactions with N-, S-,
and C-nucleophiles, and diverse related compounds were prepared, and a selection of 43 compounds was screened in preliminary
tests as anti-tumor compounds by using 4 or 5 human cancer cell lines of diverse origins. Twelve compounds were highly active
against all cell lines, 6 showed low activity, 12 no activity, and 13 exhibited a selective activity against a human small
cell lung carcinoma cell line.
Correspondence: Hans-Hartwig Otto, Department of Pharmaceutical/Medicinal Chemistry (PMC), Institute of Pharmacy, Ernst-Moritz-Arndt-University,
17487 Greifswald, Germany. 相似文献
222.
Tessendorf R Strey R Stubenrauch C 《Langmuir : the ACS journal of surfaces and colloids》2008,24(20):11390-11398
Alkyldimethyl phosphine oxides (C n DMPO) as well as alkyldiethyl phosphine oxides (C n DEPO) with chain lengths of n = 10 (decyl), 12 (dodecyl), and 14 (tetradecyl) were synthesized and purified to study how the formation of microemulsions depends on the size of the headgroup and on the length of the alkyl chain. For that purpose, equal amounts of water and n-octane were taken and surfactant was added to solubilize the two solvents. The resulting fish-shaped phase diagrams for C 10DEPO, C 12DEPO, and C 14DEPO show that the longer the hydrophobic chain the more efficient the surfactant. Simultaneously, the extension of the lamellar phase (L alpha) shifts toward lower total mass fractions gamma of the surfactant, i.e., the tendency to form lyotropic liquid crystals (LCs) increases. These trends are well-known for nonionic alkyl ethylene oxides and can thus be interpreted accordingly. What is astonishing, however, is the significant influence the size of the short side chains has. Replacing two methyl groups by two ethyl groups leads to a drastic drop of the three-phase region toward lower temperatures, while the efficiency remains nearly unchanged. Moreover, the tendency to form LCs decreases significantly. 相似文献
223.
Stubenrauch C Tessendorf R Salvati A Topgaard D Sottmann T Strey R Lynch I 《Langmuir : the ACS journal of surfaces and colloids》2008,24(16):8473-8482
Using bicontinuous microemulsions as templates opens a new field for the design of novel structures and thus novel materials, but has significant challenges due to the very small composition and temperature windows in which microemulsions are bicontinuous. In previous work we had shown that we can take a ternary base system (water-n-dodecane--C 13/15E 5), add monomer and cross-linker ( N-isopropylacrylamide and N, N'-methylenebisacrylamide) to the water phase, and add a gelator (12-hydroxyoctadecanoic acid) to the oil phase while remaining in the one-phase region of the phase diagram. It was also possible to allow the gelator to form an organogel by changing the temperature such that we crossed the sol--gel line, which fell within the one-phase region. In this work, we show conclusively that addition of the monomers and the gelator does not affect the microemulsion microstructure and that, even in the gelled state, the polymerizable microemulsion is indeed bicontinuous. 1H NMR self-diffusion, conductivity, and small-angle neutron scattering measurements all confirm the bicontinuous nature of the gelled polymerizable microemulsion. 相似文献
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228.
Renate Hoer 《Nachrichten aus der Chemie》1999,47(8):932-937
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Sofia Drakopoulou Emmanouil Orfanakis Ioulia Karagiannaki Fragiskos Gaitis Stavroula Skoulika Andreas Papaioannou George Boukouvalas George Petropoulos Vassilios Katsoudas Renate Kontzedaki Aggelos Philippidis Aikaterini Zoumi Marilena Dasenaki Nikolaos S. Thomaidis Michalis Velegrakis 《Molecules (Basel, Switzerland)》2022,27(4)
Extra virgin olive oil (EVOO) is a key component of the Mediterranean diet, with several health benefits derived from its consumption. Moreover, due to its eminent market position, EVOO has been thoroughly studied over the last several years, aiming at its authentication, but also to reveal the chemical profile inherent to its beneficial properties. In the present work, a comparative study was conducted to assess Greek EVOOs’ quality and authentication utilizing different analytical approaches, both targeted and untargeted. 173 monovarietal EVOOs from three emblematic Greek cultivars (Koroneiki, Kolovi and Adramytiani), obtained during the harvesting years of 2018–2020, were analyzed and quantified as per their fatty acids methyl esters (FAMEs) composition via the official method (EEC) No 2568/91, as well as their bioactive content through liquid chromatography coupled to high resolution mass spectrometry (LC-HRMS) methodology. In addition to FAMEs analysis, EVOO samples were also analyzed via HRMS-untargeted metabolomics and optical spectroscopy techniques (visible absorption, fluorescence and Raman). The data retrieved from all applied techniques were analyzed with Machine Learning methods for the authentication of the EVOOs’ variety. The models’ predictive performance was calculated through test samples, while for further evaluation 30 commercially available EVOO samples were also examined in terms of variety. To the best of our knowledge, this is the first study where different techniques from the fields of standard analysis, spectrometry and optical spectroscopy are applied to the same EVOO samples, providing strong insight into EVOOs chemical profile and a comparative evaluation through the different platforms. 相似文献