title: Spirodepressolide: an unusual bis-norsesquiterpene lactone from Achillea depressa Janka.
abstract: A new bis-norsesquiterpene lactone, spirodepressolide (1), has been isolated from the aerial parts of Achillea depressa Janka and its structure determined by spectroscopic methods to have a new 4-methyl-7-methylethyl-spirobicyclo[4,4]nonane skeleton.
authors.affiliation: Institute of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria. todorova@orgchm.bas.bg
authors.forename: Milka N
authors.initials: MN
authors.lastname: Todorova
authors.forename: Elena T
authors.initials: ET
authors.lastname: Tsankova
authors.forename: Elena I
authors.initials: EI
authors.lastname: Mustakerova
mesh_terms: D031162:Achillea; D006801:Humans; D007783:Lactones / Q000737:chemistry*; D008517:Phytotherapy; D035261:Plant Components, Aerial; D010936:Plant Extracts / Q000737:chemistry*; D012717:Sesquiterpenes / Q000737:chemistry*
chemical_list: D007783:Lactones; D010936:Plant Extracts; D012717:Sesquiterpenes