• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.50 no.2
• /
• pp.147-150
• /
• 2005

ent-Kaurane- and ent-pimarane-type diterpenoids were isolated from the methanol extract of Siegesbeckia pubescens by column chromatography. Their structures were elucidated as ent-16$\alpha$H,17-hydroxy-kau­ran-19-oic acid (1), ent-4,17-dihydroxy-16$\alpha$-methyl-kau­ran-19-oic acid (2), ent-16$\beta$,17-dihydroxy-kauran-19-oic acid (3), kirenol (4) and ent-16$\beta$,17,18-trihydroxy-kauran­19-oic acid (5) by spectral analysis. The cytotoxicity of these compounds in Caki cells was assayed by a cell counting kit. Only one group treated with kirenol (4), an entpimarane-type diterpenoid, showed the inhibition of the cell growth in Caki cells.

• Archives of Pharmacal Research
• /
• v.26 no.9
• /
• pp.731-734
• /
• 2003

Five known kaurane type diterpenoids, 16$\alpha$H, 17-isovaleryloxy-ent-kauran-19-oic acid (1), 16$\alpha$-hydroxy-17-isovaleryloxy-ent-kauran-19-oic acid (2), paniculoside-IV (3), 16$\alpha$-hydroxy-ent-kauran-19-oic acid (4), and ent-kaur-16-en-19-oic acid (5) were isolated from the root of Acanthopanax koreanum by repeated column chromatography and reversed phase preparative HPLC. The structures of these compounds were established from physicochemical and spectral data. Among the isolated compounds 16$\alpha$H, 17-isovaleryloxy-ent-kauran-19-oic acid (1) showed potent inhibitory activity ($IC_50$ value, 16.2 $\mu$ M) on TNF-$\alpha$ secretion from HMC-1, a trypsin-stimulated human leukemic mast cell line.