Hitorins A and B, Hexacyclic C25 Terpenoids from Chloranthus japonicus

Two novel C25 terpenoids with a 6/5/5/5/5/3 hexacyclic skeleton including one γ-lactone ring and two tetrahydrofuran rings, hitorins A (1) and B (2), were isolated from the aerial parts of Chloranthus japonicus. The structures of 1 and 2 were elucidated on the basis of spectroscopic analyses as well as TDDFT ECD calculations. Hitorins A (1) and B (2) might be biogenetically derived from eudesmane sesquiterpene and thujane monoterpene.