title: Synthesis of bicyclic gamma-ylidenetetronates.
abstract: The bicyclic gamma-ylidenetetronate motif found in several Stemona alkaloids was prepared in a stereoselective manner by addition of lithium methyl tetronate to an alkoxy oxonium ion formed from a lactone. The corresponding mixed alkyl ketal obtained was subjected to a Lewis acid-base-promoted dealkoxylation reaction to deliver the desired products.
authors.affiliation: Division of Medicinal and Natural Products Chemistry, College of Pharmacy, The University of Iowa, Iowa City 52242, USA.
authors.forename: Francisco
authors.initials: F
authors.lastname: Velázquez
authors.forename: Horacio F
authors.initials: HF
authors.lastname: Olivo
mesh_terms: D000470:Alkaloids / Q000138:chemical synthesis / Q000737:chemistry; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000138:chemical synthesis* / Q000737:chemistry; D018360:Crystallography, X-Ray; D008968:Molecular Conformation; D015394:Molecular Structure; D010084:Oxidation-Reduction
chemical_list: D000470:Alkaloids; D019086:Bridged Bicyclo Compounds, Heterocyclic