Abstract
dl-Pumiliotoxin C (1) was stereoselectively synthesized via 5β-methyl-cis-decahydroquinoline-2, 7-dione (5) which was prepared in two routes. The Diels-Alder reaction of 1, 3-bis (trimethylsiloxy)-5-methylcyclohexa-1, 3-diene (6) with acrylonitrile gave the cycloadducts (7) from which anti-8-methyl-exo-2-cyanobicyclo [2. 2. 2] oct-5-en-1-ol (2) was obtained in four steps. Treatment of the compound (2) with acid gave the keto-lactam (5). The Diels-Alder reaction of 1, 3-bis (trimethylsiloxy)-1, 3-butadiene (11) with ethyl crotonate furnished the adduct (12) from which the keto-lactam (5) was obtained via the compound (19) in seven steps. Reduction of the carbonyl group at the C7 position and introduction of the n-propyl group at the C2 position of the keto-lactam (5) gave dl-pumiliotoxin C.
