A new approach towards the synthesis of bielschowskysin: Synthesis and photochemistry of an advanced macrocyclic enedione intermediate

A novel approach towards bielschowskysin is reported based on an attempted stepwise cyclobutane formation. Synthesis of the key strained framework, containing the tricyclic ring system and all requisite carbons has been developed. While photochemical studies did not result in a late-stage Norrish–Yang cyclization, the observed isomerization could provide important insights into the synthesis of other furanocembranoids.