Capnellene, a tricyclic sesquiterpene isolated from the soft coral "Capnella imbricata", has long been a classic target compound for total synthesis due to its cis-trans-cis-tricyclic quinone core structure (formally named tricyclic [6.3.0.0²,⁶]undecane). This densely functionalized skeleton with multiple consecutive stereocenters and strained ring systems has facilitated the development of various innovative synthetic strategies.
