An Epiisopicropodophyllin Aza Analogue via Palladium-Catalyzed Pseudo-Domino Cyclization

A new aza analogue of epiisopicropodophyllin(the C-3 epimer of podophyllotoxin) has been synthesized exploiting two original strategic steps. Rings A/B and E are entered at an early stage via a cationic benzhydrylation process. A palladium-catalyzed pseudo-domino (Pd-PDOM) intramolecular process generates rings C/D in a single synthetic operation.