title: Cytotoxic ent-kaurane diterpenoids from Isodon sculponeata.
abstract: Four new ent-kaurane diterpenoids, sculponeatins F-I (1-4), together with six known compounds, sculponeatin E (5), epi-nodosin (6), epi-nodosinol (7), enmein (8), and macrocalyxoformins A and B (9 and 10), were isolated from the leaves of Isodon sculponeata. Also obtained were ursolic acid, 2alpha,3beta-dihydroxy-urs-12-en-28-oic acid, 2alpha,3beta,19alpha-trihydroxy-urs-12-en-28-oic acid, beta-sitosterol, daucosterol, quercetin, pedalitin, rosmarinic acid, caffeic acid and ethyl caffeic acid. Their structures were determined by spectral methods (1D-, 2D-NMR and MS). Some diterpenoids were tested for their cytotoxicity to inhibit three kinds of human tumor cells K562, A549 and T24. Compounds 3, 4, 6, 8, and 10 showed significant inhibitory effect toward K562 with IC(50) values ranging from 3.2 microg/ml to 8.2 microg/ml, while 3 and 6 exhibited potent antitumor activity against T24, but none exhibited cytotoxicity toward the cells of A549.
authors.affiliation: State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Academia Sinica, Kunming, P. R. China.
authors.forename: Bei
authors.initials: B
authors.lastname: Jiang
authors.forename: Ai-Jun
authors.initials: AJ
authors.lastname: Hou
authors.forename: Ma-Lin
authors.initials: ML
authors.lastname: Li
authors.forename: Sheng-Hong
authors.initials: SH
authors.lastname: Li
authors.forename: Quan-Bin
authors.initials: QB
authors.lastname: Han
authors.forename: Su-Jun
authors.initials: SJ
authors.lastname: Wang
authors.forename: Zhong-Wen
authors.initials: ZW
authors.lastname: Lin
authors.forename: Han-Dong
authors.initials: HD
authors.lastname: Sun
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry / Q000494:pharmacology*; D004224:Diterpenes / Q000737:chemistry / Q000494:pharmacology*; D004354:Drug Screening Assays, Antitumor; D006801:Humans; D020128:Inhibitory Concentration 50; D037602:Isodon; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D008517:Phytotherapy; D018515:Plant Leaves; D014407:Tumor Cells, Cultured / Q000187:drug effects
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D004224:Diterpenes