Kadsutherins A–C: Three New Dibenzocyclooctane Lignans from the Stems of Kadsura Species

Three new dibenzocyclooctane‐type lignans, kadsutherins A–C ( 1 – 3 ), were isolated from the stems of two Kadsura species. Their structures and configurations were elucidated by spectroscopic methods including 2D‐NMR and HR‐MS techniques. Kadsutherin C ( 3 ) is the first dibenzocyclooctane lignan without an oxygen‐containing substituent at C(2).