First Enantiospecific Synthesis of the Antitumor Marine Sponge Metabolite (−)-15-Oxopuupehenol from (−)-Sclareol
摘要:
[GRAPHICS]A new route toward puupehenone-related bioactive metabolites from (-)-sclareol, based on the palladium(II)-mediated diastereoselective cyclization of a drimenylphenol, is described. Utilizing this, the first enantiospecific synthesis of the antitumor and antimalarial (-)-15-oxopuupehenol, together with improved syntheses of (+)-puupehenone, (+)-puupehedione, and (+)-15-cyanopuupehenone, were accomplished.
Electrophilicaromaticbromination is the most common synthetic method used to prepare aryl bromides, which are very useful intermediates in organic synthesis. To understand the experimental results in electrophilicaromaticbrominations, ab initio calculations are used here for a tentative analysis of the positional selectivity. The calculated results agree well with the corresponding experimental