Exploiting multiple nucleophilic sites on pyrrole for the assembly of polyheterocyclic frameworks: application to a formal total synthesis of (±)-aspidospermidine

Abstract

The tricyclic ketone 19, an advanced intermediate in Aubé's recently reported synthesis of aspidospermidine (4), is prepared in twelve steps from pyrrole (3). The key transformations involve a previously described intramolecular Michael addition reaction