Rapid stereoselective access to key pumiliotoxin precursors from a common intermediate.

Epoxidation and dihydroxylation of 8-methyl-2,3,6,8a-tetrahydro-1H-indolizin-5-one proceeded from the concave face with good selectivity and gave advanced precursors for pumiliotoxin and allopumiliotoxin synthesis, respectively. The origin of the selectivity is believed to be stereoelectronic in nature and allows rapid entry to three different pumiliotoxin classes from a common intermediate.