A Decade of Strategic Advances in the Total Synthesis of Cyclopiane and Related Polycyclic Diterpenoids

Cyclopiane diterpenoids are a structurally distinctive class of fungal natural products whose 6/5/5/5 tetracyclic skeleton, enclosing six to nine contiguous stereogenic centres, including up to four allcarbon quaternary centres, poses a significant synthetic challenge.Since the first total synthesis of the family in 2016, the field has been actively studied, with significant advances over the past decade. This review surveys the structural diversity and synthetic studies of cyclopiane diterpenoids reported up to August 2026, with emphasis on the key bond-forming reactions and advances in strategic frameworks. In addition, the close biogenetic relationship with the phomopsene and spiroviolene families is examined, and syntheses of these related skeletons are discussed in a broader context.