Heteroclitin H, a new lignan from Kadsura heteroclita.

A new dibenzocyclooctadiene lignan, heteroclitin H (1), was isolated together with seven known compounds, heteroclitin D (2), interiorin B (3), interiorin (4), neokasuranin (5), interiotherin C (6), gomisin J (7) and (+)-anwulignan (8), from the stems of Kadsura heteroclita. Their structures were elucidated by spectroscopic methods. This is the first report of the isolation of compounds 3, 5, 6, 7 and 8 from K. heteroclita.