Two new ent-6,7-seco-kaurane-type diterpenoids, 15 alpha,20 beta-dihydroxy-6 beta-methoxy-6,7-seco-6,20-epoxy-ent-kaur-16-en-1,7-olide (1), 6 alpha,15 alpha-dihydroxy-20-aldehyde-6,7-seco-6,11 alpha-epoxy-ent-kaur-16-en-1,7-olide (2), together with seven known diterpenoids, enmein (3), nodosin (4), isodocarpin (5), nervosin (6), epinodosin (7), epinodosinol (8) and rabdosin (9) were isolated from the aerial part of Isodon serra. Their structures were elucidated by spectroscopic means.
