Kaurenic acid derivatives from Stevia eupatoria

Two kaurene type diterpenes were isolated from the aerial part of Stevia euphoria. Their structures and stereochemistry were established by carbon and ¹H NMR, chemical transformation and correlation with known compounds.     

Damsinic acid and ambrosanolides from vegetative ambrosia hispida

Ambrosia hispida in the vegetative state furnished large quantities of damsinic acid and smaller amounts of ambrosin and damsin. Also isolated were anhydrocoronopilin, hispidulin and the new compounds 3-hydroxyambrosin damsinate and ent-12-oxokaura-9(11),16-dien-19-oic acid.