Abstract An efficient asymmetric synthesis in nine steps of natural (−)-pumiliotoxin C (1), a decahydroquinoline alkaloid found in the skin of Central American frog species, is presented. The enantiomerically pure starting material (S)-norvalinol (3), obtained from commercial (S)-norvaline, was cyclized in a one-pot procedure to the tosylated aziridine 5. Ring opening with propargylmagnesium bromide led to the acetylenic sulfonamide ...
