Secondary Metabolites of Elaeagnus thunbergii

Chemistry of Natural Compounds -     

A New Ketone Derivative from Victoria amazonica

Chemistry of Natural Compounds - A new ketone, vicamazone (4-(2-butoxyethoxy)-4-methylpentan-2-one) (1), was isolated from the leaves of Victoria amazonica (Nymphaeaceae). The structure of the new...     

Secondary Metabolites of Mahonia bealei

Chemistry of Natural Compounds -     

A Novel Cyclopropanoid from Cinnamomum osmophloeum

Chemistry of Natural Compounds - A novel cyclopropanoid, 4-(2-(benzo[d][1,3]dioxol-5-yl)cyclopropoxy)-2,6-dimethoxyphenol (1) was isolated from the stems of Cinnamomum osmophloeum (Lauraceae). The...     

Thermal instabilities of organic carbonates with discharged cathode materials in lithium-ion batteries

Thermal instability of lithiated cathode materials with organic carbonate were investigated using DSC. Lithium transition metal oxides of LiFePO₄, LiMn₂O₄, and LiCoO₂ were mixed with diethyl carbonate, dimethyl carbonate, ethylene carbonate, ethyl methyl carbonate, and propylene carbonate then dynamically screened to about 500 °C. Curves were acquired and analyzed to determine exothermic onset temperatures and reaction enthalpies. These data for assessing the thermal hazards of lithium-ion batteries under discharged conditions were compared to those data published in the literature.     

Synthesis of selenium-containing biindolyls and their Diels–Alder reaction toward the synthesis of heteroannulated [a]- and [c]-carbazoles

We reported the first syntheses of 2- and 3-(2-(benzo[b]selenophen-2-yl)-indoles and their Diels–Alder reactions to furnish six unique annulated benzoselenphene carbazoles. This facile route can be used to synthesize selenium-containing biindolyl derivatives that possessed potential pharmaceutical activities.     

Scalar-tensor theory and the anisotropic perturbations of the inflationary universe

Inflationary higher derivative scalar-tensor theory is analyzed in this paper in a de Sitter background space. A useful model-independent formula of the Friedmann equation is derived and used to study the stability problem associated with the anisotropic perturbations of the inflationary solution. The stability conditions of the de Sitter solution are derived for a general class of models. For a simple demonstration, an induced gravity model is considered in this paper for the effects of the higher derivative interactions including a cubic term.     

The bakkenolides from the root of Petasites formosanus and their cytotoxicity.

Thirty-two new bakkenolides, bakkenolides-Db (1)--Dh(7), -Fa(8), -Fb(9), -I(10)--M(14), -Na(15), -Nb(16), -O(17)--T(22), -Ua (23), -Ub(24), -V(25)--X(27), -Ya(28), -Yb(29), -Za(30), -Zb(31) and -III(32), from the roots of Petasites formosanus together with thirty known compounds were isolated. The structures were characterized by spectral analysis. The locations, C-1 and/or C-9 of bakkenolide skeleton, of the substituents, such as acetoxy, isobutyroyloxy and isovaleroyloxy groups, can be determined by the chemical shifts of their signals and the H-1 and/H-9 in the 1H-NMR spectra. The cytotoxicity was also discussed.     

Two-photon optical-beam-induced current imaging of indium gallium nitride blue light-emitting diodes

Epilayers of packaged indium gallium nitride light-emitting diodes (LED's) are characterized by optical-beam-induced current (OBIC) and photoluminescence laser-scanning microscopy through two-photon excitation. Light scattering and absorption in the packaging material and the p-doped top layer of the LED's are greatly reduced as a result of employing a longer excitation wavelength, with energy that is less than the bandgap of the top p layer. Compared with single-photon OBIC, two-photon OBIC imaging not only exhibits superior image quality but also reveals more clearly the characteristics of the epilayers that are being focused on.