Neomacrodione: a new degraded diterpenoid from the roots of Neoboutonia macrocalyx Beng (Euphorbiaceae)

One new degraded diterpenoid 3,6-dihydroxy-1,7-dimethyl-9,10-phenantroquinone (neomacrodione) (1) together seven known compounds were isolated from the roots of Neoboutonia macrocalyx (Euphorbiaceae). The structures of the compounds were established based on their NMR and mass spectrometric data in conjunction with those previously reported in the literature. Compound (1) displayed moderate antibacterial activities.