New Tripterygium alkaloids: Synthesis of frontalin analogues and isoprenoids.

摘要

his thesis consists of three parts.;Part 1 describes the structure elucidation of four new sesquiterpene alkaloids, 1-desacetylwilfordine, 1-desacetylwilfortrine, 2-debenzoyl-2-nicotinoylwilforine, and isowilfordine, isolated from root extracts of the Chinese medicinal and insecticidal plant Tripterygium wilfordii.;The complete structures of these alkaloids have been determined by NMR experiments using 1D-;Part 2 reports the concise syntheses of 1,5-dialkyl-2,7-dioxobicyclo(3.2.1) octanes, 1,5-dialkyl-2,8-dioxobicyclo(3.2.1) octane, and 1,5-dialkyl-2,7,8-dioxobicyclo(3.2.1) octane, analogues of the Dendroctonus bark beetle pheromone frontalin.;Part 3 describes the synthesis of certain isoprenoids containing dimethylvinyl groups using a new 2,2-dimethylvinyl anion equivalent, namely the anion of methyl 2,2-dimethylsuccinate.;Alkylation and acylation of dimethyl 2,2-dimethylsuccinate were employed in the synthesis, respectively, of the model prenylated aromatic compounds, 1-aryl-3-methyl-2-butenes and the isopenoids ar-atlantone and racemic ar-turmerone.;Oxidative decarboxylation of the dicarboxylic acids and