title: Stereodivergent approach to the asymmetric synthesis of bacillariolides: a formal synthesis of ent-bacillariolide II.
abstract: [reaction: see text] Asymmetric synthesis of densely functionalized bicyclic frameworks for entry into bacillariolides I/III and ent-bacillariolide II is reported. The key features are ring-closing metathesis of a pair of diastereomerically related dienes obtained through a stereodivergent route from a R-(+)-glyceraldehyde derivative, transformation of a nonstereoselective cyclopentene ester enolate alkylation process to a completely stereoselective one through alkylation of a bulky ester enolate with a bulky electrophile, and a remote silyloxymethyl group directed epoxidation.
authors.affiliation: Department of Organic Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032, India. ocsg@iacs.res.in
authors.forename: Subrata
authors.initials: S
authors.lastname: Ghosh
authors.forename: Saikat
authors.initials: S
authors.lastname: Sinha
authors.forename: Michael G B
authors.initials: MG
authors.lastname: Drew
mesh_terms: D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000138:chemical synthesis* / Q000737:chemistry; D018360:Crystallography, X-Ray; D003500:Cyclization; D007783:Lactones / Q000138:chemical synthesis* / Q000737:chemistry; D008968:Molecular Conformation; D015394:Molecular Structure; D013237:Stereoisomerism
chemical_list: D019086:Bridged Bicyclo Compounds, Heterocyclic; D007783:Lactones; C520170:bacillariolide II; C485138:bacillariolide III