New labdane-type diterpenoids from Leonotis leonurus support circumscription of Lamiaceae s.l.

Two novel labdane-type diterpenoids were isolated from the leaves of Leonotis leonurus (Lamiaceae): 9,13-Epoxy-6-hydroxy-labdan-16,15-olide and 9,13:15,16-Diepoxy-6,16-labdanediol. Their occurrence supports recent phylogenetic reassessments of the Lamiaceae and Verbenaceae, which reflect in a more broadly circumscribed Lamiaceae.Figure optionsDownload as PowerPoint slideHighlights
► Two new labdane-type diterpenoids isolated from the leaves of Leonotis leonurus.
► Compounds currently isolated possess the lactone between C-4 and C-6.
► Chemotaxonomic support provided for a broader recircumscribed Lamiaceae.
► Findings assist in focussing bioprospecting for forskolin-type compounds.