著者

釜野 徳明 黒田 直孝 木津 治久 小宮山 寛機

出版者

天然有機化合物討論会実行委員会

雑誌

天然有機化合物討論会講演要旨集

巻号頁・発行日

vol.39, pp.505-510, 1997

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Euphorbia sieboldiana Morr. et Decne. (Euphorbiaceae) is named as "Natsutodai" in Japan and is distributed widely in the mountain field. The roots of this plant are used as a diuretic drug by Japanese people. As regards the constituents of this plant, although over ten of three cyclic diterpenes are isolated by some Chinese groups, no work for biological activities has been reported. Our investigation was undertaken to discover biologically active components of this plant, because the extract showed an inhibition of cell division for fertilized sea urchin egg. In this paper, we report the isolation and structural elucidation of three new jatrophane A type diterpenes, named sieboldianines A(1), B(2), and C(3) (Fig. 2) having the antineoplastic activities, from the CH_2Cl_2 fraction of "Natsutodai" extract by repeated chromatography. Isolation (Fig. 1) was contacted with the two kind of bioassay, which are the inhibition of cell division for fertilized sea urchin egg and the cytotoxicity for human peripheral blood cancer HL-60 cell. Structural elucidation of three new compounds 1〜3 was based on their spectral data such as the infra-red spectra, mass spectra, and especially detail 1D and 2D nuclear magnetic resonance (NMR) spectra(Table 1). From ^1H, ^<13>C NMR data, the jatrophane A skeleton of sieboldianines A(1), B(2), C(3), were reduced, in addition to the presence of two cyclic structures. The 2D HMBC experiment was utilized for established of carbon sequence and two ring condensation. The position of hydroxy esters (-OAc and -OBz) were carefully assigned. Finally, the biogenesis of sieboldianines was discussed (Fig. 3). Also. the strong activities of sieboldianines A(1), B(2), and C(3) for HL-60 cells were indicated in Table 1, together with the interesting activities for the resistant both P388/ADM and P388/VCR cells(Table 2).