A highly conjunctive beta-keto phosphonate: application to the synthesis of pyridine alkaloids xestamines C, E, and H.

The synthesis of a novel beta-keto gamma-xanthyl phosphonate has been achieved. This highly conjunctive reagent has been utilized in a combination of radical and ionic reactions to create new carbon-carbon bonds. Its usefulness was demonstrated by realizing the first total synthesis of naturally occurring pyridine alkaloids xestamines C, E, and H.