title: Total synthesis of leucosceptroids A and B.
abstract: Leucosceptroids A and B are sesterterpenoids with potent antifeedant and antifungal activities. A more efficient gram-scale total synthesis of leucosceptroid B and the first total synthesis of leucosceptroid A are presented. The key transformations include an aldol reaction between a substituted dihydrofuranone and an (S)-citronellal-derived aldehyde, a SmI2-mediated intramolecular ketyl-olefin radical cyclization, and final-stage alcohol oxidation.
authors.affiliation: State Key Laboratory of Bioorganic & Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Lu, Shanghai 200032 (China).
authors.forename: Sheng
authors.initials: S
authors.lastname: Guo
authors.forename: Jie
authors.initials: J
authors.lastname: Liu
authors.forename: Dawei
authors.initials: D
authors.lastname: Ma
mesh_terms: D000447:Aldehydes / Q000737:chemistry; D000475:Alkenes / Q000737:chemistry; D000935:Antifungal Agents / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D002384:Catalysis; D020231:Colletotrichum / Q000187:drug effects; D018360:Crystallography, X-Ray; D003500:Cyclization; D005609:Free Radicals / Q000737:chemistry; D007454:Iodides / Q000737:chemistry; D008968:Molecular Conformation; D012232:Rhizoctonia / Q000187:drug effects; D012493:Samarium / Q000737:chemistry; D054830:Sesterterpenes / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology
chemical_list: D000447:Aldehydes; D000475:Alkenes; D000935:Antifungal Agents; D005609:Free Radicals; D007454:Iodides; D054830:Sesterterpenes; C552074:leucosceptroid A; C569088:leucosceptroid B; D012493:Samarium; C116609:3-hydroxybutanal; C409809:samarium diiodide
keywords: aldol reaction; cyclization; natural products; sesterterpenoids; total synthesis