title: Hemistepsins with cytotoxic activity from Hemisteptia lyrata.
abstract: Two sesquiterpene lactones were isolated from Hemisteptia lyrata Bunge (Compositae). Their structures were elucidated by spectroscopic methods as recently known hemistepsin and the new 6-O-(2-methylpropenoyl)-3-hydroxy-4(15), 10(14), 11(13)-guaiatrien-12,8-olide. The two hemistepsin derivatives were examined for their in vitro cytotoxic activity against human cell lines such as UACC 62, HCT 15, UO-31, PC-3 and A549. Growth inhibitory property was determined by in vitro treatment of the respective cell lines using the sulforhodamine B assay (SRB). Both compounds exhibited significant cytotoxic activity (IC50 < 4.3 micrograms/ml) on all five human cell lines tested.
authors.forename: D S
authors.initials: DS
authors.lastname: Jang
authors.forename: M S
authors.initials: MS
authors.lastname: Yang
authors.forename: T J
authors.initials: TJ
authors.lastname: Ha
authors.forename: K H
authors.initials: KH
authors.lastname: Park
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D019659:Asteraceae / Q000737:chemistry*; D004354:Drug Screening Assays, Antitumor; D006801:Humans; D015394:Molecular Structure; D013057:Spectrum Analysis; D014407:Tumor Cells, Cultured
chemical_list: D000972:Antineoplastic Agents, Phytogenic