Polyquinane
A polyquinane or polyquinene is a saturated or unsaturated, respectively, polycyclic hydrocarbon consisting of fused five-membered rings. The simplest member is the bicyclic compound bicyclo[3.3.0]octane. Other members are triquinacene and dodecahedrane.
The compound triquinacene (tricyclo[5.2.1.-04,10]deca-2,5,8-triene) is the second member of a family of polyquinenes. It was synthesized in 1964 in the group of R. B. Woodward in connection with its suspected homoaromatic properties (although it was found to have no such properties), and also as part of a failed attempt to synthesize the then-elusive and much-coveted compound dodecahedrane. Unlike the related pentacene, triquinacene is stable, and has a melting point of 18°C. The final step of its synthesis is a Cope elimination.
...
Wikipedia