title: ent-Pimarane derivatives from Dysoxylum hainanense.
abstract: Four ent-pimarene diterpenoids. ent-18-acetoxy-8(14)-pimarene-15S, 16-diol, ent-18-acetoxy-16-hydroxy-8(14)-pimaren-15-one, ent-16,18-dihydroxy-8(14)-pimaren-15-one and ent-19-nor-4,16,18-trihydroxy-8(14)-pimaren-15-one, together with three known damarane triterpenoids, richenoic acid, eichleriainic acid and shoreic acid were isolated from the bark of Dysoxyhum hainanense Merr. Their structures were elucidated on the basis of spectroscopic techniques. The absolute configurations of four diterpenoids were assigned as ent-pimarene type by chemical transformation and by co-occurrence in the plant as well as by negative optical rotations for four compounds.
authors.affiliation: Laboratory of Phytochemistry, Kunming Institute of Botany, The Chinese Academy of Sciences, Yunnan, People's Republic of China. x_dluo@hotmail.com
authors.forename: X D
authors.initials: XD
authors.lastname: Luo
authors.forename: S H
authors.initials: SH
authors.lastname: Wu
authors.forename: Y B
authors.initials: YB
authors.lastname: Ma
authors.forename: D G
authors.initials: DG
authors.lastname: Wu
mesh_terms: D045784:Abietanes; D004224:Diterpenes / Q000737:chemistry / Q000302:isolation & purification*; D010944:Plants / Q000737:chemistry*; D013057:Spectrum Analysis
chemical_list: D045784:Abietanes; D004224:Diterpenes; C433018:pimarane