title: New weakly cytotoxic eremophilane sesquiterpenes from the roots of Ligularia virgaurea.
abstract: Six new eremophilane sesquiterpenes, including a novel nortrieremophilane carbon skeleton, were isolated from the roots of Ligularia virgaurea. Their structures were elucidated as 3 alpha,4 alpha-epoxy-6 alpha-(2'-methylacryloyl)oxy-8 alpha-methoxyeremophil-7(11)-en-8 beta,12-olide (1), 3 alpha,4 alpha-epoxy-6 alpha-(2'-methylacryloyl)oxy-8 alpha-ethoxyeremophil-7(11)-en-8 beta,12-olide (2), 1 beta,10 beta-epoxy-6 beta-(2'-methylacryloyl)oxy-8 beta-methoxyeremophil-7(11)-en-8 alpha,12-olide (3), 1 beta,10 beta-epoxy-6 beta-angeloyloxy-8 beta-methoxyeremophil-7(11)-en-8 alpha,12-olide (4), 6 beta-methoxyeremophil-7(11)-en-8 beta,12-olide (5), and 5 beta-angeloyloxy-3a,4,5,6,7,7a-hexahydro-3a beta-methyl-1 H-indene-2,4 beta-dioic acid methyl ester (6) by spectral methods, including IR, HR-ESI-MS, 1D and 2D NMR techniques. All of compounds were evaluated for their in vitro cytotoxic activities against human hepatoma (SMMC-7721), human promyelocytic leukemia (HL-60), and human hepatocyte (L-02) cells.
authors.affiliation: State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, People's Republic of China.
authors.forename: Zhan-Xin
authors.initials: ZX
authors.lastname: Zhang
authors.forename: Chang-Jun
authors.initials: CJ
authors.lastname: Lin
authors.forename: Ping-Lin
authors.initials: PL
authors.lastname: Li
authors.forename: Zhong-Jian
authors.initials: ZJ
authors.lastname: Jia
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D019659:Asteraceae; D045744:Cell Line, Tumor / Q000187:drug effects; D006801:Humans; D009281:Naphthalenes / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use; D008517:Phytotherapy; D010936:Plant Extracts / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D018517:Plant Roots; D000081223:Polycyclic Sesquiterpenes; D012717:Sesquiterpenes / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D009281:Naphthalenes; D010936:Plant Extracts; D000081223:Polycyclic Sesquiterpenes; D012717:Sesquiterpenes; C018286:eremophilane compounds