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71.
Prof. Dr. Hans-René Bjørsvik Prof. Dr. Bjørn Tore Gjertsen Dr. Vijayaragavan Elumalai 《ChemMedChem》2020,15(10):862-870
A previously designed and developed 12-step total synthesis that includes [1,1′-biphenyl]-2-amine and carbazole intermediates and that ultimately produces the carbazole alkaloid carbazomycin G was exploited as a screening compound library with the goal of identifying potential lead compound(s) with cytotoxic effect. These compounds were investigated by using in-vitro tests involving the two human cell lines HL-60 and MOLM-13, which both model acute myeloid leukaemia (AML). The in-vitro biological test results were used together with the molecular structures of the various intermediates in a concise SAR analysis. Several of the intermediates revealed cytotoxicity (IC50<10−4 M), although the final natural product carbazomycin G did not reveal cytotoxicity versus the two said human cell lines. 相似文献
72.
Peter?S.?Piispanen Bj?rn?Hedman Torbj?rn?NorinEmail author 《Journal of surfactants and detergents》2002,5(2):165-168
The syntheses of derivatives of dehydroabietic acid suitable for further manipulation into surfactants are presented. The
compounds are produced at very high yields and purity. They contain several different functional groups, e.g., carboxylic
acid, amine, ester, alcohol, and an aromatic group. The functional groups are useful as the linking unit to the hydrophilic
part in synthesizing surfactants. 相似文献
73.
Dorota Johansson Björn Bergenståhl 《Journal of the American Oil Chemists' Society》1992,69(8):728-733
The influence of water on the interactions between fat and sugar crystals dispersed in triglyceride (vegetable) oils was qualitatively
estimated from sedimentation and rheological experiments. The experiments were performed both with and without food emulsifiers
(monoglycerides and lecithins) present in the oil. The effects of minor natural oil components (nontriglycerides) on the interactions
and on emulsifier adsorption to the crystals were examined by comparing a commercial refined oil and a chromatographically
purified oil. The results show that water generally increases the adhesion between fat and sugar crystals in oils and also
increases the surface activity of the oil-soluble food emulsifiers. Minor oil components give a small increase in the adhesion
between fat and sugar crystals in oils, but do not influence the adsorption of food emulsifiers in any systematic way. 相似文献
74.
Thomas Schulz Timmy Reimann Arne Bochmann Andre Vogel Beate Capraro Björn Mieller Steffen Teichert Jörg Töpfer 《Journal of the European Ceramic Society》2018,38(4):1600-1607
The sintering behavior and the thermoelectric performance of Ca3Co4O9 multilayer laminates were studied, and a multilayer thermoelectric generator was fabricated. Compacts and multilayer samples with anisotropic microstructure and residual porosity were obtained after conventional sintering at 920 °C, whereas dense and isotropic multilayer samples were prepared by firing at 1200 °C and reoxidation at 900 °C. A hot-pressed sample has a dense and anisotropic microstructure. Samples sintered at 920 °C exhibit low electrical conductivity due to the low density, whereas the Seebeck coefficient is not sensitive to preparation conditions. However, thermal conductivity of multilayers is very low, and, hence acceptable ZT values are obtained. A transversal multilayer thermoelectric generator (TMLTEG) was fabricated by stacking layers of Ca3Co4O9 green tapes, AgPd conductor printing, and co-firing at 920 °C. The TMLTEG has a power output of 3 mW at ΔT = 200 K in the temperature interval of 25 °C to 300 °C. 相似文献
75.
76.
Comparative Assessment of Complex Stabilities of Radiocopper Chelating Agents by a Combination of Complex Challenge and in vivo Experiments 下载免费PDF全文
Shanna Litau Dr. Uwe Seibold Alicia Vall‐Sagarra Prof. Dr. Gert Fricker Prof. Dr. Björn Wängler Priv.‐Doz. Dr. Carmen Wängler 《ChemMedChem》2015,10(7):1200-1208
For 64Cu radiolabeling of biomolecules to be used as in vivo positron emission tomography (PET) imaging agents, various chelators are commonly applied. It has not yet been determined which of the most potent chelators—NODA‐GA ((1,4,7‐triazacyclononane‐4,7‐diyl)diacetic acid‐1‐glutaric acid), CB‐TE2A (2,2′‐(1,4,8,11‐tetraazabicyclo[6.6.2]hexadecane‐4,11‐diyl)diacetic acid), or CB‐TE1A‐GA (1,4,8,11‐tetraazabicyclo[6.6.2]hexadecane‐4,11‐diyl‐8‐acetic acid‐1‐glutaric acid)—forms the most stable complexes resulting in PET images of highest quality. We determined the 64Cu complex stabilities for these three chelators by a combination of complex challenge and an in vivo approach. For this purpose, bioconjugates of the chelating agents with the gastrin‐releasing peptide receptor (GRPR)‐affine peptide PESIN and an integrin αvβ3‐affine c(RGDfC) tetramer were synthesized and radiolabeled with 64Cu in excellent yields and specific activities. The 64Cu‐labeled biomolecules were evaluated for their complex stabilities in vitro by conducting a challenge experiment with the respective other chelators as challengers. The in vivo stabilities of the complexes were also determined, showing the highest stability for the 64Cu–CB‐TE1A‐GA complex in both experimental setups. Therefore, CB‐TE1A‐GA is the most appropriate chelating agent for *Cu‐labeled radiotracers and in vivo imaging applications. 相似文献
77.
78.
C?t?lin Voiniciuc Bo Yang Maximilian Heinrich-Wilhelm Schmidt Markus Günl Bj?rn Usadel 《International journal of molecular sciences》2015,16(2):3452-3473
For more than a decade, the Arabidopsis seed coat epidermis (SCE) has been used as a model system to study the synthesis, secretion and modification of cell wall polysaccharides, particularly pectin. Our detailed re-evaluation of available biochemical data highlights that Arabidopsis seed mucilage is more than just pectin. Typical secondary wall polymers such as xylans and heteromannans are also present in mucilage. Despite their low abundance, these components appear to play essential roles in controlling mucilage properties, and should be further investigated. We also provide a comprehensive community resource by re-assessing the mucilage phenotypes of almost 20 mutants using the same conditions. We conduct an in-depth functional evaluation of all the SCE genes described in the literature and propose a revised model for mucilage production. Further investigation of SCE cells will improve our understanding of plant cell walls. 相似文献
79.
Carolin Wang-Hansen Per Ericsson Björn Lundberg Magnus Skoglundh Per-Anders Carlsson Bengt Andersson 《Topics in Catalysis》2013,56(1-8):446-451
The reactivity and reaction kinetics of particulate matter (PM) from direct injected gasoline (GDI) engines has been studied by O2 and NO2 based temperature programmed and isothermal step-response experiments, and the PM nano-structure has been characterized using HRTEM. The reactivity of the PM samples collected in filters during on-road driving was found to increase in the following order: Printex U < diesel < gasoline PI ≈ gasoline DI < ethanol for O2 based combustion. The activation energies for O2 and NO2 based oxidation of PM collected from a GDI engine in an engine bench set-up was estimated to 146 and 71 kJ/mol respectively, which is comparable to corresponding values reported for diesel and model soot. Similar nano-structure features (crystallites plane dimensions, curvature and relative orientation) as observed for diesel soot were observed for gasoline PM. 相似文献
80.
Marco Maspero Prof. Clelia Dallanoce Prof. Dr. Björn Wängler Prof. Dr. Carmen Wängler Dr. Ralph Hübner 《ChemMedChem》2022,17(8):e202100739
In the present study we describe and explain an aberrant behavior in terms of receptor binding profile of a fluorescein-based multimodal imaging agent for gastrin releasing peptide receptor (GRPR) visualization by elucidating a chelating mechanism on sodium ions of its fluorescent dye moiety. This hypothesis is supported by both biological results and spectroscopic analyses of different fluorescein-carrying conjugates and an equally charged set of analogous tartrazine-based GRPR-binding imaging agents. Fluorescein interacts with sodium which reduces the overall negative charge of the dye molecule by one. This reduction in apparent total net charge explains the exceptional behavior found for the fluorescein-based multimodal bioconjugate in the context of the charge-cell binding correlation hypothesis. 相似文献