15-O-methyl-18-oxoneovibsanin F (5), 2-O-methylneovibsanin H (6), 2-O-methylneovibsanin I (7), neovibsanin G (8), and 14-epi-neovibsanin G (9), were isolated from a methanol extract of the leaves of Viburnum awabuki. Their structures were elucidated to be uniquely rearranged vibsane-type diterpenes by spectroscopic analyses and comparison of NMR data with those of previously reported vibsane-type diterpenes. In addition
九种新的二萜,新vibsanin D(1),7-epi-neovibsanin D(2),15-O-methylneovibsanin F(3),14-epi-15-O-methylneovibsanin F(4),15-O-methyl-从
甲醇中分离出18-oxoneovibsanin F(5),2-O-methylneovibsanin H(6),2-O-methylneovibsanin I(7),neovibsanin G(8)和14-epi-neovibsanin G(9)。荚Vi的叶子的
提取物。通过光谱分析和NMR数据与先前报道的vi烷型二萜的比较,阐明了它们的结构是唯一重排的b烷型二萜。另外,用高压
汞块照射
甲醇中的vibsanin B(12)导致直接形成新vibsanins A(14)和B(15)。这些结果为了解11元vibsanins向新vibsanins的
生物遗传学相互转化提供了线索。