title: New eremophilenolides from Cacalia pilgeriana.
abstract: Five new eremophilenolides and a known sesquiterpene were isolated from the methanol extract of the roots of Cacalia pilgeriana. Their structures were identified as 1 beta-hydroxy-2 beta-methyl-senecioyloxyeremophil-7(11)-en-8 beta(12)-olide (1), 1 beta-hydroxy-2 beta-methylsenecioyloxy-8 alpha-methoxyeremophil-7(11)-en- 8 beta(12)-olide, 2 beta-hydroxy-3 beta-methylsenecioyloxyeremophil-7(11)-en-8 alpha(12)-olide ( 3), 2 beta,8 beta-dihydroxy-3 beta-methylsenecioyloxyeremophil-7(11)-en-8 alpha(12)-olide and 1 beta,8 beta-dihydroxy-2 beta,3 alpha-diangeloyloxyeremophil-7(11)-en-8 alpha(12)-olide ( 5) and caryolane-1,9 beta-diol by spectroscopic methods including 2D-NMR techniques ( (1)H- (1)H COSY, HMQC, HMBC) and HR-ESI-MS. The structure and relative stereochemistry of compound 1 were unequivocally established by X-ray diffraction analysis. Bioassays showed compounds 3 and 5 to possess strong cytotoxic activity in vitro against human leukemia cells (HL-60) (IC (50) < 15 microg mL (-1)). The structure-activity relationship is discussed.
authors.affiliation: State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, P. R. China.
authors.forename: Er-Wei
authors.initials: EW
authors.lastname: Li
authors.forename: Jing
authors.initials: J
authors.lastname: Pan
authors.forename: Kun
authors.initials: K
authors.lastname: Gao
authors.forename: Zhong-Jian
authors.initials: ZJ
authors.lastname: Jia
mesh_terms: D019659:Asteraceae / Q000737:chemistry*; D016923:Cell Death / Q000187:drug effects; D045744:Cell Line, Tumor; D018360:Crystallography, X-Ray; D006801:Humans; D020128:Inhibitory Concentration 50; D007938:Leukemia / Q000473:pathology; D015394:Molecular Structure; D018517:Plant Roots / Q000737:chemistry; D012717:Sesquiterpenes / Q000737:chemistry* / Q000494:pharmacology; D013329:Structure-Activity Relationship
chemical_list: D012717:Sesquiterpenes