title: Total synthesis of (+/-)-frondosin B and (+/-)-5-epi-liphagal by using a concise (4+3) cycloaddition approach.
abstract: A recently developed (4+3) cycloaddition between dienes and furfuryl alcohols, as precursors of oxyallyl-type cations, has been used as a key step in the racemic syntheses of two natural products: frondosin B and liphagal. This work demonstrates the synthetic potential of this cycloaddition reaction, and offers a short synthetic route to an interesting family of natural products. A full account of these synthetic studies is presented, further illustrating the mechanism, scope, and limitations of this straightforward synthetic method for seven-membered rings.
authors.affiliation: Department of Organic Chemistry, Ghent University, Krijgslaan 281 S4, 9000 Gent (Belgium).
authors.forename: Duchan R
authors.initials: DR
authors.lastname: Laplace
authors.forename: Bart
authors.initials: B
authors.lastname: Verbraeken
authors.forename: Kristof
authors.initials: K
authors.lastname: Van Hecke
authors.forename: Johan M
authors.initials: JM
authors.lastname: Winne
mesh_terms: D001688:Biological Products / Q000138:chemical synthesis / Q000737:chemistry; D018360:Crystallography, X-Ray; D061565:Cycloaddition Reaction; D003508:Cycloheptanes / Q000737:chemistry; D006576:Heterocyclic Compounds, 4 or More Rings / Q000138:chemical synthesis* / Q000737:chemistry; D008968:Molecular Conformation; D013237:Stereoisomerism; D013729:Terpenes / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D001688:Biological Products; D003508:Cycloheptanes; D006576:Heterocyclic Compounds, 4 or More Rings; D013729:Terpenes; C421322:frondosin B; C513880:liphagal
keywords: cycloaddition reactions; cycloheptanes; furans; natural products; total synthesis