Three new antinociceptive diterpenoids from the roots of .

Two new grayanane-type ( and ) and one new kalmane-type diterpenoids (), together with 16 known compounds, were isolated from the roots of The structures of new compounds were fully determined on the basis of spectroscopic analysis, including HRESIMS, 1 D and 2 D NMR data. An acetic acid-induced writhing test in mice was proceeded to evaluate the antinociceptive activities of compounds , , and . Compared to vehicle-injected mice, compounds , , and 1 showed significant antinociceptive effects with writhe inhibition rates of 45.8%-64.2% at a dose of 0.1 mg/kg, and compounds , and showed significant antinociceptive effects with writhe inhibition rates of 33.9%-64.8% at a dose of 5 mg/kg. Compound showed potent antinociceptive effects with writhe inhibition rates of 86.1% and 54.7% at doses of 8 mg/kg and 0.8 mg/kg, respectively. [Formula: see text].