Diterpenoid lanceolatins A–G from Cephalotaxus lanceolata and their anti-inflammatory and anti-tumor activities

Seven new diterpenoids lanceolatins, A–G (1–7), together with five known diterpenoids (8–12), were isolated from the branches and leaves of Cephalotaxus lanceolata. The structures of the new diterpenoids were elucidated based on spectroscopic analysis, including 1D, 2D NMR, and HR-ESI-MS. Single crystal X-ray diffraction (CuKα radiation) was employed to confirm the structure of lanceolatin G (7), and its absolute configuration was finally established. Compound 12 showed significant inhibition against human tumor cell lines HCT116 and HepG2 with IC50 values of 0.17 and 0.63 μg mL−1, respectively, whereas compounds 3–5 can inhibit nitric oxide (NO) release in LPS-induced RAW264.7 macrophages with IC50 values of 8.72, 10.79, and 12.73 μM, respectively.