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  • Author: Hiromitsu Takayama x
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Abstract

Two new prenylated flavones, artoindonesianins Z-1 (1) and Z-2 (2), together with two other known prenylated flavones, artobiloxantone (3) and cycloartobiloxanthone (4), had been isolated and identified from the chloroform extract of the tree bark of Artocarpus lanceifolius. The structures of these compounds were determined based on spectroscopic data, including UV, IR, 1-D and 2-D NMR, and mass spectra. The significance of the presence of the isolated compounds to the chemotaxonomy of Artocarpus is briefly discussed.

A continuing study on the phytochemical constituents of Garcinia atroviridis Griff ex T. Anders (Guttiferae) has led to the isolation of a new prenylated hydroquinone from the roots of the plant. The compound has been elucidated to be 4-methylhydroatrovirinone, primarily by the use of gradient NMR and mass spectroscopy. The roots also yielded the known morelloflavone and its 7-O-β-D-glucopyranoside, fukugiside, together with 14-cis-docosenoic

acid.

A new methylated flavonol, 5,7,2 ′,4 ′-tetrahydroxy-3-methoxyflavone (1), had been isolated from the methanol extract of the wood of Morus australis, along with nine known compounds, kuwanon C (2), morusin (3), morachalcone A (4), oxyresveratrol (5), 4 ′-(2-methyl-2-buten- 4-yl)oxyresveratrol (6), moracins M (7) and C (8), alboctalol (9), and macrourin B (10). The structures of these compounds were determined based on spectral evidence, including UV, IR, NMR, and mass spectra. Cytotoxic properties of compounds 1 →10 were evaluated against murine leukemia P-388 cells. The prenylated stilbene 6 and 2-arylbenzofuran 8, and morusin (3) were found to have strong cytotoxic effects with IC50 values of 6.9, 8.7, and 10.1 μM, respectively.

A new flavanone, 7-hydroxy-5,6-dimethoxyflavanone (1), together with three other flavonoids, didymocarpin (2), 2′,4′-dihydroxy-5′,6′-dimethoxychalcone (3), and isodidymocarpin (4), had been isolated from the methanol extract of the tree bark of Cryptocarya costata. The structures of these compounds were determined based on spectral evidence, including UV, IR, 1-D and 2-D NMR, and mass spectra. Cytotoxic properties of compounds 1-4 were evaluated against murine leukemia P-388 cells. The chalcones 3 and 4 were found to have substantial cytotoxicity with IC50 of 5.7 and 11.1 μᴍ, respectively.