| Abstract: | Two new ent-kaurene diterpenoids, 15α-acetoxyl-6,11α-epoxy-6α-hydroxy-20-oxo-6,7-seco-ent-kaur-16-en-1,7-olide (1), 15α-hydroxy-20-oxo-6,7-seco-ent-kaur-16-en-1,7α(6,11α)-diolide (2), together with ten known compounds (5-14) were isolated from the leaves of Isodon rubescens. Their structures were elucidated mainly by various spectroscopic techniques and finally confirmed by single-crystal X-ray diffraction. Compounds 1, 2, 8 and 12 were evaluated for their cytotoxicities against EC-1, U87, A549, MCF-7 and Hela cell lines. |
