Through a unified synthetic strategy, appropriately functionalized bicyclic
starting materials can be elaborated via Ni(II)/Cr(II) macrocylization to
[9.3.1] bicycles. Elaboration of these core structures allows access to pho
mactin C/D analogues and establishes the first synthetic approach to phomac
tin A affording an intact octahydrochromene/macrocyclic ring system.