Lin N-H,
Overman LE,
*
Rabinowitz MH,
Robinson LA,
Sharp MJ,
Zablocki J.
University of California, Irvine, USA
Efficient Total Syntheses of Pumiliotoxins A and B. Applications of Iodide-Promoted Iminium Ion−Alkyne Cyclizations in Alkaloid Construction.
J. Am. Chem. Soc. 1996;
118: 9062-9072
Keywords
(+)-pumiliotoxin A - dendrobatid alkaloid - Ireland–Claisen rearrangement - Parikh–Doering oxidation - Corey–Fuchs reaction - iodide-promoted aza-Prins reaction
Significance
Overman and co-workers report the total synthesis of ( + )-pumiliotoxin A. The alkaloid was isolated in 1967 from the skin of the Panamanian poison frog Dendrobates pumilio. The skin secretions of these frogs have been employed by the Noanamá and the Emberá Native American tribes to poison blow darts.
Comment
Alkyne E is coupled with proline-derived building block F through an aluminum-mediated epoxide opening. The octahydroindolizine motif is constructed through an iodide-promoted aza-Prins reaction. The synthesis was completed after a deiodination and Birch reduction sequence, thus giving access to ( + )-pumiliotoxin A.
