title: Synthesis of Briarane Diterpenoids: Biomimetic Transannular Oxa-6π electrocyclization Induced by a UVA/UVC Photoswitch.
abstract: A biomimetic synthesis of briareolate ester B (3) from briareolate ester L (1) via the intermediate briareolate ester G (2) has been achieved through a unique transannular oxa-6π electrocyclization induced by UVA light. UVC irradiation of 3 triggered a rapid retro-6π electrocyclization to establish an unprecedented photochromic switch. In the ground state, reaction of 1 led to the formation of a polycyclic γ-spiroketal γ-lactone 5, architecturally related to the ether-bridged cembranoids of the cladiellin class.
authors.affiliation: Department of Chemistry and Biochemistry, Florida Atlantic University , Boca Raton, Florida 33431, United States.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Hall
authors.affiliation: Department of Chemistry and Biochemistry, Florida Atlantic University , Boca Raton, Florida 33431, United States.
authors.forename: Stéphane P
authors.initials: SP
authors.lastname: Roche
authors.affiliation: Department of Chemistry and Biochemistry, Florida Atlantic University , Boca Raton, Florida 33431, United States.
authors.forename: Lyndon M
authors.identifier: 0000-0003-0909-830X
authors.initials: LM
authors.lastname: West
mesh_terms: D032701:Biomimetics; D003500:Cyclization; D004224:Diterpenes / Q000737:chemistry*; D004987:Ethers; D007783:Lactones; D015394:Molecular Structure; D014466:Ultraviolet Rays
chemical_list: D004224:Diterpenes; D004987:Ethers; D007783:Lactones