The major diterpenoids of the genus Arctopus (Apiaceae) with notes on their chemotaxonomic and medicinal significance

► The main diterpenoids of Arctopus were identified for the first time. ► Manool and ent-trachyloban-19-oic acid are two major diterpenes. ► Methyl-16β-hydroxy-ent-kaur-11-en-19-oate is a minor kaurene ester. ► The chemical similarity between Arctopus and Alepidea supports molecular systematic findings. ► These biologically active diterpenes contribute to the medicinal value of Arctopus.