New 20(10→5)abeo‐Diterpenoids from Pygmaeopremna herbacea

Two new 20(10→5) abeo ‐abietune diterpenoids, pygmaeooins B ( 1 ) and C ( 2 ), have been isolated from the roots of Pygmaeopremna herbacea (Verbenaceae). Their structures were elucidated on the basis of spectroscopic data, and chemically, both compounds were correlated with each other. The absolute configurations were assigned tentatively on the basis of biogenetic pathway.