Structure Elucidation of “Hydroxycycloaraneosene” by Unambiguous Total Synthesis. An Eight-Membered Ring Formation via a Lewis Acid-Catalyzed Ene-Reaction
was further converted to cycloaraneosene and its congener, “hydroxycycloaraneosene”. Total synthesis of the latter established its structure to be 8β-hydroxy derivative, not as the originally-proposed 9α-.