The synthesis of aryl tricyclic compounds having two benzo groups fused around a central seven-membered ring has been important to the development of two classes of drugs, the antidepressants [ 11 and the non-steroidal antiin- flammatory drugs (NSAIDS) 121. Many heterocycles have appeared in the central ring. Substituted 1 1H-dibenzo- [b,e][l,4]dioxepins (1 IH-DBDO) were synthesized for use as antidepressants [3]. More recently, the IlH-DBDO ring system has appeared as ...