Taxodin A, a Cytotoxic C 30 Terpenoid from Taxodium mucronatum with a Unique Skeleton.

Taxodin A (1), a unique C 30 terpenoid featuring an unprecedented skeleton composed of an abietane-type diterpene and a menthane-type monoterpene, was obtained from the leaves and branches of Taxodium mucronatum. The structure and absolute configuration of compound 1 was unequivocally established by the combination of extensive spectroscopic analyses and X-ray single-crystal diffraction analysis. Compound 1 exhibited potent cytotoxic activities against A549, SMMC-7721, MDA-MB-231, and SW480 cell lines with IC 50 values of 15.35±0.73, 8.49±0.35, 17.53±0.79, 18.93±0.60 μM, respectively.