Chemical constituents of Ajuga forrestii and their anti-ferroptosis activity.

ABSTRACT

Six new neoclerodane diterpenoids (1-6), along with ten known compounds (7-16), were isolated from Ajuga forrestii. Their structures were elucidated by HRESIMS, 1D and 2D NMR, ECD calculation, and single-crystal X-ray diffraction analysis. The structure of a known neoclerodane diterpene ajudecunoid C (6) was revised based on the reported NMR empirical rules. All the isolates were evaluated for their inhibitory effect on RSL3-induced ferroptosis in HT22 mouse hippocampal neuronal cells. Among them, compounds 8, 9, and 12 significantly inhibited RSL3-induced ferroptosis with EC50 values of 0.45 µM, 0.076 µM, and 0.14 µM.