Cytotoxic diterpenoids from Jatropha curcas cv. nigroviensrugosus CY Yang Roots

An investigation of phytochemicals from the roots of Jatropha curcas cv. nigroviensrugosus resulted in the isolation of twenty diterpenoids, including lathyranlactone, an unusual diterpenoid lactone possessing a 5/13/3 tricyclic skeleton, jatrocurcasenones A–E and jatrophodiones B–E, as well as 10 known analogues. All isolates were evaluated for cytotoxicity against the HL-60, SMMC-772, A-549, MCF-7 and SW480 human tumor cell lines using the MTS viability assay. Four of the known analogues showed cytotoxic activity in these cell lines, with IC50 values ranging from 2.0 to 23.0 μM. Moreover, the assessment of their cytotoxic structure–activity relationships showed the epoxy ring between C-5 and C-6 and the hydroxyl group at C-2 were the key functionalities for cytotoxicity.