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81.
Shosuke Yamamura Masatoki Ito Masatake Niwa Izumi Hasegawa Shigeru Ohba Yoshihiko Saito 《Tetrahedron letters》1981,22(8):739-740
Tricyclosolidagolactone has been isolated from the leaves of L., and its structure also been elucidated on the basis of its spectral data coupled with an X-ray crystallographic analysis of the corresponding trihydroxy compound produced on LiAlH4 reduction. 相似文献
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83.
Three novel 22-beta-O-spirostanol oligoglycosides, torvosides J (1), K (2) and L (3) have been isolated from the fruits of Solanum torvum SWARTZ and their chemical structures have been characterized based on the spectroscopic means. They are worth of note as rare 22-beta-O-spirostanol glycosides. 相似文献
84.
85.
Hiroharu Suzuki Hidehiko Yashima Toshiyuki Hirose Mitsuru Takahashi Yoshihiko Moro-Oka Tsuneo Ikawa 《Tetrahedron letters》1980,21(51):4927-4930
Trans-tetrahydrofuran-3-carbaldehydes are prepared by ruthenium-catalyzed isomerization of 4,7-dihydro-1,3-dioxepines and subsequent Lewis acid-catalyzed 1,3-alkyl migration. 相似文献
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88.
Mohammad Mizanur Rahman Kazuaki Ninomiya Chiaki Ogino Nobuaki Shimizu 《Ultrasonics sonochemistry》2010,17(4):738-743
A non-woven titanium dioxide (TiO2) fabric was applied to disinfection by ultrasound (US) irradiation, and the disinfection efficiency and lipid peroxidation of Escherichia coli (E. coli) cell membrane were evaluated to investigate the killing process. The addition of non-woven TiO2 fabric enhanced hydroxyl (OH) radical generation and disinfection efficiency. Judging from the disinfection experiments using glutathione or t-butanol as a radical scavenger, the OH radical played a major role in cell killing in sonodynamic disinfection with non-woven TiO2 fabric. Moreover, to understand the detailed killing process, damage to cell membrane was also evaluated using a diphenyl-1-pyrenylphosphine (DPPP) fluorescent probe, which detects the membrane’s lipid peroxidation. The addition of non-woven TiO2 fabric aggravated this peroxidation. This aggravation was caused by the OH radical according to an assay using a radical scavenger. From these results, it was concluded that non-woven TiO2 fabric as a sonocatalyst promoted peroxidation of the polyunsaturated phospholipid component of the lipid membrane initially and induced a major disorder in the E. coli cell membrane under US irradiation. 相似文献
89.
We observed self-formations of multiple lasing channels and two-dimensional lasing patterns consisting of composite local modes having different lasing frequencies in a laser-diode-pumped wide-aperture thin-slice solid-state laser with imperfect reflective end surfaces. Global patterns resembling higher-order Hermite-Gaussian modes or possessing N-fold rotational symmetries were experimentally shown to appear due to the standard polished surface roughness of closely spaced reflective ends and nonlinear modal interactions. 相似文献
90.
The reactivity of neurotransmitters toward hydrogen abstraction by an active oxygen species (the cumylperoxyl radical) is comparable to that of a strong antioxidant such as catechin due to the strong intramolecular hydrogen bonding, which has been successfully detected by ESR. 相似文献