title: Total synthesis of diterpenoid steenkrotin A.
abstract: A concise and diastereoselective total synthesis of the diterpenoid (±)-steenkrotin A is described for the first time. The strategy mainly features three key ring formations: 1) a rhodium-catalyzed O-H bond insertion followed by an intramolecular carbonyl-ene reaction to build up the tetrahydrofuran subunit; 2) sequential SmI2 -mediated Ueno-Stork and ketyl-olefin cyclizations to construct the [5,7] spirobicyclic skeleton; and 3) an intramolecular aldol condensation/vinylogous retro-aldol/aldol sequence to form the final six-membered ring with inversion of the relative configuration at the C7 position.
authors.affiliation: Department of Chemistry, Zhejiang University, 148 Tianmushan Road, Hangzhou 310028 (China).
authors.forename: Saiyong
authors.initials: S
authors.lastname: Pan
authors.affiliation: Department of Chemistry, Zhejiang University, 148 Tianmushan Road, Hangzhou 310028 (China).
authors.forename: Jun
authors.initials: J
authors.lastname: Xuan
authors.affiliation: Department of Chemistry, Zhejiang University, 148 Tianmushan Road, Hangzhou 310028 (China).
authors.forename: Beiling
authors.initials: B
authors.lastname: Gao
authors.affiliation: Department of Chemistry, Zhejiang University, 148 Tianmushan Road, Hangzhou 310028 (China).
authors.forename: An
authors.initials: A
authors.lastname: Zhu
authors.affiliation: Department of Chemistry, Zhejiang University, 148 Tianmushan Road, Hangzhou 310028 (China). hfding@zju.edu.cn.
authors.forename: Hanfeng
authors.initials: H
authors.lastname: Ding
mesh_terms: D004224:Diterpenes / Q000138:chemical synthesis* / Q000737:chemistry; D008958:Models, Molecular; D008968:Molecular Conformation; D013237:Stereoisomerism
chemical_list: D004224:Diterpenes; C567997:steenkrotin A
keywords: aldol reaction; carbenoids; natural products; radical reactions; total synthesis