title: Steroidal saponins from Myriopteron extensum and their cytotoxic activity.
abstract: Two new steroidal saponins, extensumsides A ( 1) and B ( 2), were isolated from the whole plants of Myriopteron extensum (Wight) K. Schum. Their structures were elucidated as 17 beta-uzarigenin-3- O- beta-glucopyranosyl-(1-->6)- beta-glucopyranosyl-(1-->4)- beta-thevetopyranosyl-(1-->4)- beta-cymaropyranoside ( 1) and 12-(3-methylbut-2-enoyloxy)pregn-5-en-20-one 3- O-[beta-cymaropyranosyl-(1-->4)-beta-cymaropyranosyl-(1-->4)-beta-thevetopyranosyl-(1-->4)-(6- O-sulfo-beta-glucopyranoside)] ( 2) on the basis of chemical and spectral evidence. Extensumside A exhibited significant cytotoxicity against eight cancer cell lines with a mean GI (50) value of 0.346 microg/mL.
authors.affiliation: Chengdu Institute of Biology, the Chinese Academy of Sciences, Chengdu 610-041, P. R. China.
authors.forename: Ming-Fu
authors.initials: MF
authors.lastname: Yang
authors.forename: Yu-Yuan
authors.initials: YY
authors.lastname: Li
authors.forename: Xiao-Ping
authors.initials: XP
authors.lastname: Gao
authors.forename: Bo-Gang
authors.initials: BG
authors.lastname: Li
authors.forename: Guo-Lin
authors.initials: GL
authors.lastname: Zhang
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology* / Q000627:therapeutic use; D029062:Apocynaceae; D045744:Cell Line, Tumor / Q000187:drug effects; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D008517:Phytotherapy; D010936:Plant Extracts / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology* / Q000627:therapeutic use; D012503:Saponins / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D010936:Plant Extracts; D012503:Saponins