title: Taxane diterpenoids from the stem bark of Taxus mairei.
abstract: Three new 11(15-->1)-abeo-taxanes, taxumairols U-W (1-3), have been isolated from extracts of the stem bark of Formosan Taxus mairei. The structures of 1-3 were identified as 5alpha,7beta,9alpha,13alpha,20-pentaacetoxy-2alpha,10beta,15-trihydroxy-11(15-->1)-abeo-taxene, 5alpha,7beta,9alpha,20-tetraacetoxy-2alpha,10beta,13alpha,15-tetrahydroxy-11(15-->1)-abeo-taxene, and 2alpha,4alpha,7beta,10beta-tetraacetoxy-5beta,20-epoxy-9alpha,13alpha,15-trihydroxy-11(15-->1)-abeo-taxene, respectively, on the basis of 2D NMR techniques including COSY, HSQC, HMBC, and NOESY experiments as well as chemical reactions of compounds 1-3 to give 4 (5alpha,7beta,9alpha,10beta,13alpha,20-hexaacetoxy-2alpha,15-dihydroxy-11(15-->1)-abeo-taxene) and 5 (4alpha,7beta,10beta-triacetoxy-9alpha,13alpha-dibenzoxy-5beta,20-epoxy-2alpha,15-dihydroxy-11(15-->1)-abeo-taxene), which are also novel taxane derivatives. Taxumairols U (1) and V (2) exhibited significant cytotoxicities against human hepatoma tumor cells, while taxumairol W (3) was inactive.
authors.affiliation: Institute of Marine Resources, National Sun Yat-sen University, 70 Lien-Hai Road, Kaohsiung, Taiwan, Republic of China. ycshen@mail.nsysu.edu.tw
authors.forename: Y C
authors.initials: YC
authors.lastname: Shen
authors.forename: C V
authors.initials: CV
authors.lastname: Prakash
authors.forename: Y J
authors.initials: YJ
authors.lastname: Chen
authors.forename: J F
authors.initials: JF
authors.lastname: Hwang
authors.forename: Y H
authors.initials: YH
authors.lastname: Kuo
authors.forename: C Y
authors.initials: CY
authors.lastname: Chen
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D006528:Carcinoma, Hepatocellular / Q000378:metabolism*; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D017239:Paclitaxel / Q000031:analogs & derivatives / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D018547:Plant Stems / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry*; D013329:Structure-Activity Relationship; D043823:Taxoids; D014407:Tumor Cells, Cultured / Q000187:drug effects
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D043823:Taxoids; C435868:taxumairol U; C435869:taxumairol V; C435870:taxumairol W; D017239:Paclitaxel