Dimericursones A and B: two unprecedented hexacyclic dimeric diterpenoids from the root barks of Jatropha curcas.

Dimericursones A and B (1 and 2), two unprecedented hexacyclic dimeric diterpenoids, were obtained from the root barks of Jatropha curcas. Their structures were elucidated by extensive spectroscopic analysis, electronic circular dichroism calculations, and single-crystal X-ray diffraction. Dimericursone B (2) showed significant inhibition on nitric oxide production of lipopolysaccharide-induced RAW264.7 macrophages with IC50 values of 5.65 µM.