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Taibaijaponicains C and D: two new diterpenoids from Isodon japonica
1School of Chemistry and Material Science, Shaanxi Normal University, Xi'an, Shaanxi 710062, China. baolinli@snnu.edu.cn
Abstract:
Two new C-20-oxygenated ent-kaurene diterpenoids, taibaijaponicains C and D, together with five known compounds, were isolated from the ethanol extract of the leaves and branches of Isodon japonica (Burm. f.) Hara. The structures of new compounds were elucidated as 1 alpha-aectoxy-7 beta,12 beta,15 alpha-trihydroxy-16 alpha-hydroxymethyl-7,20-epoxy- ent-kaurane and 1 alpha-acetoxy-2 beta,3 alpha,6 beta,7 beta,12 beta-pentahydroxy-7,20;19,20-diepoxy- ent-kaur-16-en-15-one, respectively, on the basis of detailed spectroscopic analysis.
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