2004 年 52 巻 7 号 p. 879-882
From the leaves of the endemic Vietnamese medicinal plant Croton tonkinensis GAGNEP. (Euphorbiaceae) the four new ent-kaurane-type diterpenoids ent-1α,14α-diacetoxy-7β-hydroxykaur-16-en-15-one (1), ent-1α,7β-diacetoxy-14α-hydroxykaur-16-en-15-one (2), ent-18-acetoxy-14α-hydroxykaur-16-en-15-one (3), and ent-(16S)-18-acetoxy-7β-hydroxykauran-15-one (4) were isolated. Their structures were elucidated by spectroscopic analyses.