Sesqui- and Diterpenoids from the Radix of Curcuma aromatica

Eight new sesquiterpenoids (18), two new diterpenoids (9 and 10), and 17 known sesqui- and diterpenoids (1127) were isolated from the radix of Curcuma aromatica. Among these compounds, 1 is an unprecedented guaiane with unique cyclopropane and furan functionalities, and 9 is the first atisane diterpenoid isolated from a Curcuma species. Their 2D and 3D structures were established using HRESIMS and spectroscopic methods, including ECD and IECD data. The antioxidant activities of compounds 127 were evaluated based on their ability to protect PC12 cells against H2O2-induced damage, with 1, 2, 58, 11, 12, 14, 16, 18, and 19 exhibiting notable antioxidant effects on oxidative injury induced by H2O2.