title: Total Synthesis and Structure Revision of (-)-Siphonodictyal B and Its Biomimetic Conversion into (+)-Liphagal.
abstract: The structure of siphonodictyal B has been reassigned on the basis of the total synthesis of both possible C-8 epimers. The revised structure of siphonodictyal B was converted into liphagal by acid catalyzed rearrangement of a proposed epoxide intermediate. This biomimetic cascade features a succession of four distinct reactions (epoxidation, o-quinone methide formation, ring expansion, and benzofuran formation) that occur in a one-pot operation under mild conditions. During these studies we also isolated a surprisingly stable o-quinone methide that supports our mechanistic proposal for liphagal biosynthesis.
authors: Department of Chemistry, University of Adelaide , Adelaide, SA 5005, Australia.
authors: Adrian W
authors: AW
authors: Markwell-Heys
authors: Department of Chemistry, University of Adelaide , Adelaide, SA 5005, Australia.
authors: Kevin K W
authors: KK
authors: Kuan
authors: Department of Chemistry, University of Adelaide , Adelaide, SA 5005, Australia.
authors: Jonathan H
authors: JH
authors: George
mesh_terms: D002384:Catalysis; D006873:Hydroquinones / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D012717:Sesquiterpenes / Q000138:chemical synthesis* / Q000737:chemistry; D013729:Terpenes / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D006873:Hydroquinones; D012717:Sesquiterpenes; D013729:Terpenes; C513880:liphagal; C552187:siphonodictyal B1