A new neo-clerodane diterpene from Ajuga decumbens.

A new neo-clerodane diterpene, named ajugacumbin J (1), together with 13 known compounds (2-14) was isolated from Ajuga decumbens. The structure of ajugacumbin J (1) was elucidated by 1D and 2D NMR spectra and MS. Ajugacumbin J (1) and ajugacumbin D (5) exhibited inhibition of lipopolysaccharide-induced nitric oxide production in RAW 264.7 macrophages with an IC50 value of 46.2 and 35.9 μM, respectively.