title: Total Syntheses of 7,20-Oxa-Bridged Dinorditerpenes: Antihepatitis C Virus Active (+)-Elevenol from Flueggea virosa and (+)-Przewalskin.
abstract: An efficient stereoselective synthetic approach to 7-20 oxa-bridged abietane type natural products is reported. Key steps are an asymmetric Mukaiyama aldol addition to construct the C3 stereocenter and an intramolecular organocatalyzed Stetter-type Michael addition followed by a Tishchenko reaction. An intramolecular lactone-enolate arylation delivers the tetracyclic skeleton. This synthetic strategy was applied for the first total synthesis of (+)-elevenol, an antihepatitis C active compound from Fluegga virosa, and the first total synthesis of (+)-przewalskin.
authors.affiliation: Fachbereich Chemie, Philipps-University Marburg , Hans-Meerwein-Strasse 4, D-35043 Marburg, Germany.
authors.forename: Michel
authors.initials: M
authors.lastname: Fischer
authors.affiliation: Fachbereich Chemie, Philipps-University Marburg , Hans-Meerwein-Strasse 4, D-35043 Marburg, Germany.
authors.forename: Klaus
authors.initials: K
authors.lastname: Harms
authors.affiliation: Fachbereich Chemie, Philipps-University Marburg , Hans-Meerwein-Strasse 4, D-35043 Marburg, Germany.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Koert
mesh_terms: D045784:Abietanes / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D000998:Antiviral Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D018360:Crystallography, X-Ray; D004224:Diterpenes / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D019665:Euphorbiaceae / Q000737:chemistry*; D016174:Hepacivirus / Q000187:drug effects*; D008826:Microbial Sensitivity Tests; D008958:Models, Molecular; D015394:Molecular Structure
chemical_list: C000627524:(+)-przewalskin; D045784:Abietanes; D000998:Antiviral Agents; D004224:Diterpenes; C000627525:elevenol