Anti-inflammatory Diterpenoid Alkaloids from Aconitum taipeicum

Aconitaimine A, a new hetidine-type C20-diterpenoid alkaloid (1), and three known aconitine-type C19-diterpenoid alkaloids (2-4) were isolated from the roots of Aconitum taipeicum.The structures of all isolates were identified by spectroscopic methods and comparison with literature data.Compounds 1 and 2 showed inhibition of nitric oxide production in RAW 264.7 macrophages stimulated by lipopolysaccharide with IC50 values of 30.5 and 4.7 M compared to positive control (dexamethasone, IC50 = 12.9 M).