title: Annotinolides A-C, Three Lycopodane-Derived 8,5-Lactones with Polycyclic Skeletons from Lycopodium annotinum.
abstract: Three novel 7,8-seco-lycopodane-derived 8,5-lactones (annotinolides A-C, 1-3) were isolated from Lycopodium annotinum. Their structures were elucidated by spectroscopic methods and single-crystal X-ray diffraction. Compound 1 possesses an unusual cyclopropane ring constructed through a hitherto unknown C-6/C-12 bond. Compound 2 represents the first 7,8-seco-lycopodane-derived alkaloid with a rare cyclobutane ring formed by a new C-12/C-15 linkage, while the C-8/C-15 bond remains. Compound 3 contains an unprecedented 12-spiro-9,12-γ-lactone moiety. Their plausible biosynthetic pathways and antiaggregation effects on amyloid-β1-42 are also presented.
authors: Department of Natural Products Chemistry, School of Pharmacy, Fudan University , Shanghai 201203, China.
authors: Yu
authors: Y
authors: Tang
authors: Department of Natural Products Chemistry, School of Pharmacy, Fudan University , Shanghai 201203, China.
authors: Juan
authors: J
authors: Xiong
authors: State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences , Shanghai 201203, China.
authors: Jing-Jing
authors: JJ
authors: Zhang
authors: State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences , Shanghai 201203, China.
authors: Wei
authors: W
authors: Wang
authors: State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences , Shanghai 201203, China.
authors: Hai-Yan
authors: HY
authors: Zhang
authors: Department of Natural Products Chemistry, School of Pharmacy, Fudan University , Shanghai 201203, China.
authors: Jin-Feng
authors: JF
authors: Hu
mesh_terms: D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000737:chemistry / Q000302:isolation & purification*; D007783:Lactones / Q000737:chemistry / Q000302:isolation & purification*; D032502:Lycopodium / Q000737:chemistry*; D008968:Molecular Conformation; D011083:Polycyclic Compounds / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D019086:Bridged Bicyclo Compounds, Heterocyclic; D007783:Lactones; D011083:Polycyclic Compounds