Seven-membered vibsane-type diterpenes with a 5,10-cis relationship from Viburnum awabuki.
New five seven-membered vibsane-type diterpenes named 5-epi-vibsanin C, 5-epi-vibsanin H, 5-epi-vibsanin K, 18-O-methyl-5-epi-vibsanin K and 5-epi-vibsanin E have been isolated from the leaves of Viburnum awabuki (Caplifoliaceae). Their structures have been elucidated by analyses of spectroscopic data and comparison of their spectral data with those of the previously known seven-membered vibsane-type diterpenes. The occurrence of these seven-membered vibsane-type diterpenes with a cis relationship on the C-5 and C-10 positions in nature have been predicted by conformational analysis of vibsanin B, an eleven-membered vibsane-type diterpene. Vibsanin C, 5-epi-vibsanin C and 5-epi-vibsanin H exhibited moderate cytotoxic activities on KB cells.
Fukuyama
Yoshiyasu
Y
Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Japan. fukuyama@ph.bunri-u.ac.jp
Minami
Hiroyuki
H
Matsuo
Asami
A
Kitamura
Kanako
K
Akizuki
Mie
M
Kubo
Miwa
M
Kodama
Mitsuaki
M
D004224:Diterpenes / Q000737:chemistry* / Q000302:isolation & purification; D009682:Magnetic Resonance Spectroscopy; D019684:Magnoliopsida / Q000737:chemistry*; D015394:Molecular Structure; D016339:Spectrometry, Mass, Fast Atom Bombardment; D013055:Spectrophotometry, Infrared
D004224:Diterpenes; C000598979:vibsanin B