A synthetic approach to anthraquinone xanthone heterodimers is described. The route to the pentacydic core features an efficient assembly of a benzocycloheptenone via a new intramolecular oxidative arylation of an enol ether and a Hauser-Kraus annulation aldol reaction sequence to access the characteristic bicydo[3.2.2]nonene motif. Acremoxanthone A is synthesized in 10 steps from commercially available material to demonstrate the application of this approach.