Denudatine-type diterpenoid alkaloids from an aqueous extract of the lateral root of Aconitum carmichaelii

Abstract Five new denudatine-type diterpenoid alkaloids (1–5), along with the known analogue aconicarmine (6), were isolated from an aqueous decoction of the lateral roots of Aconitum carmichaelii (fu-zi). Their structures were determined by spectroscopic data analysis and electronic circular dichroism (ECD) calculations. Compound 5 is the first denudatine-type diterpenoid alcohol iminium alkaloid, which could be partially transformed into the aza acetal form in pyridine-d 5. Compound 5 inhibited mice writhing in an acetic acid-induced writhing assay. Graphical Abstract