title: Skeleton-rearranged pentacyclic diterpenoids possessing a cyclobutane ring from Euphorbia wallichii.
abstract: [structure: see text] Two novel rearranged trachylobane diterpenoids, designated as wallichanol A (2) and wallichanol B (3), consisting of an unprecedented pentacyclic skeleton named wallichane with a cyclobutane ring, and a new ent-trachylobane diterpenoid, 3-oxo-ent-trachyloban-17-oic acid (1), were isolated from the roots of Euphorbia wallichii. Their structures were elucidated by comprehensive analysis of 2D-NMR spectroscopic data, with the stereochemistry of 1 confirmed by X-ray crystallographic study. All of these compounds potently block osteoclastogenesis in vitro, suggesting a potential therapeutic application in prevention of osteoporosis.
authors.affiliation: Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, People's Republic of China.
authors.forename: Li
authors.initials: L
authors.lastname: Pan
authors.forename: Ping
authors.initials: P
authors.lastname: Zhou
authors.forename: Xiaofeng
authors.initials: X
authors.lastname: Zhang
authors.forename: Shulin
authors.initials: S
authors.lastname: Peng
authors.forename: Lisheng
authors.initials: L
authors.lastname: Ding
authors.forename: Samuel X
authors.initials: SX
authors.lastname: Qiu
mesh_terms: D001862:Bone Resorption / Q000517:prevention & control; D018360:Crystallography, X-Ray; D003503:Cyclobutanes / Q000737:chemistry*; D004224:Diterpenes / Q000737:chemistry* / Q000302:isolation & purification* / Q000494:pharmacology; D028481:Euphorbia / Q000737:chemistry*; D008968:Molecular Conformation; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D010010:Osteoclasts / Q000187:drug effects; D010024:Osteoporosis / Q000517:prevention & control*; D018517:Plant Roots / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry*
chemical_list: D003503:Cyclobutanes; D004224:Diterpenes; C518445:wallichanol A; C518446:wallichanol B