Cytotoxic Bisnor- and Norditerpene Dilactones Having 7a,80t-Epoxy-9,11-enolide Substructure from Podocarpus macrophyllus D. DON

摘要

Fourteen new bisnor- and norditerpene dilactones, makilactones E-R, having a 7a: 8a-epoxy-9,11-enolidesubstructure, were isolated from a methanolic extract of the root and the bark of Podocarpus macrophyllus D.DON (Podocarpaceae) with thirteen known bisnor- and norditerpenoids, and the structures of those new bisnor-and norditerpenoids were determined on the basis of their spectroscopic studies. Of the thirteen known ones iso-lated, the structures of two, i.e., podolactone B and inumakilactone B, were revised on the basis of X-ray crystal-lographic analysis and spectroscopic analysis. Many of the compounds of this type isolated in this study showedpotent cytotoxic activities against P388 murine leukemia cells.