New Labdane-Type Diterpenoids from Leonurus heterophyllus SW.

Abstract

Five new natural labdane-type diterpenoids (5—9), designated leoheteronins A—E, together with four known diterpenoids (1—4), two phytosterols as a mixture of β-sitosterol and stigmasterol, and the flavone genkwanin (10) were isolated from the aerial parts of Leonurus heterophyllus SW. (Lamiaceae) collected in northern Vietnam. Compound 1 was isolated for the first time from a Leonurus species, and 10 is considered to be a chemotaxonomic marker of the Leonurus genus. Their structures were determined using spectroscopic analyses.