Lathyrane and Jatrophane Diterpenoids from Evaluated for Cytotoxicity against a Paclitaxel-Resistant A549 Human Lung Cancer Cell Line.

A phytochemical investigation on the aerial parts of resulted in the isolation of 27 macrocyclic diterpenoids, including three previously unreported lathyrane derivatives, euphohelioscopoids A-C (-). Their structures were elucidated by spectroscopic data interpretation. Three jatrophanes, euphoscopin C (), euphorbiapene D (), and euphoheliosnoid A (), showed cytotoxicity against a paclitaxel-resistant A549 human lung cancer cell line with IC values of 6.9, 7.2, and 9.5 μM, respectively, but were inactive against the parent A549 human lung cancer cell line (IC > 10 μM). It was found that jatrophanes with a benzoyloxy or a nicotinoyloxy substituent at C-7 showed more potent cytotoxic activity than their analogues containing acetyloxy and hydroxy groups at this position.