title: Three new C-14 oxygenated taxanes from the wood of Taxus yunnanensis.
abstract: Three new C-14 oxygenated taxane-type diterpenes, hongdoushans A-C (1-3), were isolated from the wood of Taxus yunnanensis together with four known diterpenes and two lignans. The absolute stereochemistry of the 2-methylbutyryloxy group attached at C-14 of the taxane skeleton was determined to be S by GC analysis of the methyl ester of 2-methylbutyric acid obtained after alkaline hydrolysis of 1 and 4 followed by treatment with CH(2)N(2). The complete stereostructure of the known compound 2alpha,5alpha,10beta-triacetoxy-14beta-[(S)-2-methylbutyryloxy]-4(20),11-taxadiene (4) was established for the first time. The isolates obtained were evaluated for their antiproliferative activity toward murine colon 26-L5 carcinoma and human HT-1080 fibrosarcoma cell lines.
authors.affiliation: Institute of Natural Medicine, Toyama Medical and Pharmaceutical University, 2630-Sugitani, Toyama 930-0194, Japan.
authors.forename: Arjun H
authors.initials: AH
authors.lastname: Banskota
authors.forename: Tepy
authors.initials: T
authors.lastname: Usia
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Tezuka
authors.forename: Kyoji
authors.initials: K
authors.lastname: Kouda
authors.forename: Nhan Trung
authors.initials: NT
authors.lastname: Nguyen
authors.forename: Shigetoshi
authors.initials: S
authors.lastname: Kadota
mesh_terms: D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D001952:Bridged-Ring Compounds / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D002470:Cell Survival / Q000187:drug effects; D003110:Colonic Neoplasms; D004224:Diterpenes / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D004354:Drug Screening Assays, Antitumor; D004365:Drugs, Chinese Herbal / Q000737:chemistry*; D005354:Fibrosarcoma; D006801:Humans; D006868:Hydrolysis; D051379:Mice; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D017239:Paclitaxel / Q000031:analogs & derivatives; D010946:Plants, Medicinal / Q000737:chemistry*; D013237:Stereoisomerism; D043823:Taxoids; D020946:Taxus / Q000737:chemistry*; D014197:Trees / Q000737:chemistry*; D014407:Tumor Cells, Cultured / Q000187:drug effects
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D001952:Bridged-Ring Compounds; D004224:Diterpenes; D004365:Drugs, Chinese Herbal; D043823:Taxoids; C471827:hongdoushan A; C471829:hongdoushan B; C471828:hongdoushan C; C080625:taxane; D017239:Paclitaxel