1-epi-deacetylaconitine, a new norditerpenoid alkaloid from Aconitum nemorum

A new norditerpenoid alkaloid, 1-epi-deacetylaconitine (1), along with thre e known compounds, neoline, songorine and 12-epi-napelline, was isolated fr om the roots of Aconitum nemorum. The structure of the new compound was elu cidated on the basis of 1D and 2D NMR, EIMS and FABMS experiments. The stru cture of 1-epi-deacetylaconitine is unusual because it is the only aconitin e series norditerpenoid alkaloid in which the I-methoxyl group exists in th e beta -configuration and an intramolecular hydrogen bond is present betwee n the nitrogen atom and the hydrogen of 3 alpha -hydroxyl group.