hamigerans D, G, L, and N–Q has been accomplished. A convergent approach was used to build the basic tricarbocyclic ring system bearing a 5‐6‐6 structure. A sequence of oxidative cleavage, homologation, and ring regeneration provided access to the 5‐7‐6 skeleton of hamigeran G. Based on the biogenetic hypothesis, elegant and highly efficient biomimetic transformations of hamigeran G into hamigerans D, N–Q