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GLC-MS analysis of methylated bhilawanol from S. anacardium nuts and its oxidation product, the methyl ester of an aromatic carboxylic acid, conclusively proved that it contains more than seven closely related compounds. Two of them are major components which were isolated and shown to be 1-pentadec-Δ5′-enyl-2,3-dimethoxybenzene (I) and 1-pent biflavanoids A, B and C have been also isolated from defatted nuts of S. anacardium. The first of these has been characterized as its methyl ethers. A1 and A2, for which biflavanone structures (VI) and (VII) are suggested on the basis of chemical and spectral evidence. The biflavanones B and C have been also characterized as their methyl ethers. Suggested structures are O-methyl derivatives of a IB-3′, IIA-8-binaringenin (XIV) for the former and IB-3′, IIA-8-biliquiritigenin (XV) for the latter.  相似文献   
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Parameter estimations were made for the reversed-phase adsorption of perillyl alcohol (POH), a potent anti-cancer agent, on octadecylsilyl-silica gel (ODS). The average particle diameter of ODS was about 15 μm, and the particles were packed in the column (3.9 × 300 mm). The mobile phase used was a mixture of acetonitrile and water, in which the acetonitrile ranged between 50 and 70 (v/v %). The first absolute moment and the second central moment were determined from the chromatographic elution curves by moment analysis. Experiments were carried out using POH solutions within the linear adsorption range. The fluid-to-particle mass transfer coefficient was estimated using the Wilson-Geankoplis equation. The axial dispersion coefficient and the intraparticle diffusivity were determined from the slope and intercept of a plot ofH vs 1/u 0, respectively. The contributions of each mass-transfer step were axial dispersion, fluid-toparticle mass transfer, and intraparticle diffusion.  相似文献   
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From the whole plants of Aster himalaicus, a new eudesmane‐type sesquiterpene, 1‐oxoeudesm‐11(13)‐eno‐12,8α‐lactone, along with twelve known compounds, was isolated. The structures of all compounds have been elucidated on the basis of spectroscopic data, including IR, EI‐MS, HR‐ESI‐MS, and 1D‐ and 2D‐NMR data.  相似文献   
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From the neutral fraction of the acid hydrolysate of the saponin of Acacia concinna pods, acacic acid lactone 3β-acetate and a new nor-triterpene ‘acacidiol’ have been isolated. The latter is shown to be 28-noroleana-16,18-diene-3β,21β-diol.  相似文献   
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