title: 6,7-seco-ent-kaurane diterpenoids from Isodon sculponeatus with cytotoxic activity.
abstract: Six new 6,7-seco-ent-kaurane diterpenoids, sculponeatins N-S (1-6, resp.), together with eleven known analogues, 7-17, were isolated from the aerial parts of Isodon sculponeatus. The structures of compounds 1-6 were elucidated by spectroscopic methods including extensive 1D- and 2D-NMR experiments, as well as HR-ESI-MS analysis. All diterpenoids obtained were assayed for their cytotoxic activity against K562 and HepG2 human tumor cell lines. Among them, compound 1 showed the most significant cytotoxicity with the IC₅₀ values of 0.21 and 0.29 μM, respectively. The structure-activity relationships are discussed.
authors.affiliation: Kunming Institute of Botany, Chinese Academy of Sciences, P R China.
authors.forename: Xian
authors.initials: X
authors.lastname: Li
authors.forename: Jian-Xin
authors.initials: JX
authors.lastname: Pu
authors.forename: Zhi-Ying
authors.initials: ZY
authors.lastname: Weng
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhao
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhao
authors.forename: Wei-Lie
authors.initials: WL
authors.lastname: Xiao
authors.forename: Han-Dong
authors.initials: HD
authors.lastname: Sun
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry* / Q000302:isolation & purification / Q000633:toxicity; D045744:Cell Line, Tumor; D045786:Diterpenes, Kaurane / Q000737:chemistry* / Q000302:isolation & purification / Q000633:toxicity; D006801:Humans; D037602:Isodon / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008968:Molecular Conformation; D010936:Plant Extracts / Q000737:chemistry / Q000633:toxicity; D021241:Spectrometry, Mass, Electrospray Ionization; D013329:Structure-Activity Relationship
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D045786:Diterpenes, Kaurane; D010936:Plant Extracts