Novel C-35 terpenoids from the Panamarian liverwort Plagiochila Moritziana

A new class of C-35 terpenoids is described from Hepaticae: plagiospirolide A and plagiospirolide B, two novel heptacyclic spiro-terpenes were isolated from the Panamanian liverwort Plagiochila moritziana Lindbg. & Gott. Structures were determined by MS, extensive NMR studies and X-ray crystallographic analysis. The compounds may be biosynthesized by condensation of a sesquiterpenoid and a diterpenoid unit in a Diels-Alder like reaction