title: New cytotoxic steroid from Stachyurus imalaicus var. himalaicus.
abstract: A phytochemical study of the ethanolic extract of Stachyurus imalaicus var. himalaicus was undertaken and as a result a new polyoxygenated steroid, named stachsterol ((20S)-20, 25-dihydroxy-4-cholesten-3-one, 1) and three known ecdysteroids, 20-hydroxyecdysone (2), 20-hydroxyecdysone-20, 22-monoacetonide (3) and polypodine B-20,22-monoacetonide (4), were isolated. Their structures were elucidated by spectroscopic methods, including UV, NMR, MS and HR-MS. The purified product 1 was found to have in vitro cytotoxic activity against human Hela cell lines with an IC50 value of 2.5 microg/mL. This is the first time that phytoecdysteroids have been found in the genus Stachyurus.
authors.affiliation: Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming 650091, PR China. wangys99@hotmail.com
authors.forename: Yun-Song
authors.initials: YS
authors.lastname: Wang
authors.forename: Jing-Hua
authors.initials: JH
authors.lastname: Yang
authors.forename: Shi-De
authors.initials: SD
authors.lastname: Luo
authors.forename: Hong-Bin
authors.initials: HB
authors.lastname: Zhang
authors.forename: Liang
authors.initials: L
authors.lastname: Li
mesh_terms: D016923:Cell Death / Q000187:drug effects; D006367:HeLa Cells; D006801:Humans; D019684:Magnoliopsida / Q000737:chemistry*; D013058:Mass Spectrometry; D010840:Phytosterols / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology
chemical_list: D010840:Phytosterols