The Total Synthesis of Diacetyloxodenudatine

Abstract

The total synthesis of racemic diacetyloxodenudatine ( 2 ) 1s described.Treatment of this material with LiAlH 4 in dioxane at reflux caused the reduction of not only the lactam but also the exocycllc double bond and yielded racemic dihydrodenudatine (23).--Ten years ago we have conjectured on the basis of a few degradation reactions and some biogenetic considerations, the structure (1) (configuration not implied) as one of two basic possibilities for the alkaloid denudatine. 1 A short time later, the structural problem was solved rigorously when two independent crystallographic investigations have shown denudatine to be represented by the formula (A) .2r3As the sole member of the ring B bridged atisine group of alkaloids, denudatine has considerable biogenetic importance.4