Phytotoxic cis-clerodane diterpenoids from the Chinese liverwort Scapania stephanii

Twelve cis-clerodane diterpenoids, including stephanialides A-E (1-5), were isolated from the Chinese liverwort Scapania stephanii. Six of these cis-clerodane diterpenoids demonstrated phytotoxic activities by inhibiting root elongation of the seeds of Arabidopsis thaliana, Lepidium sativum, and Brassica pekinensis.