A new bisnorditerpenoid alkaloid lamarckinine (1) containing a C(19) N- azomethine group was isolated from Aconitum lamarckii Reichenb., besides neoline, 1,14-diacetylneoline, 8-O-ethylbenzoylaconine, columbianine, delcosine, lycoctonine, and 18-methoxygadesine. The structure of the new alkaloid was elucidated by 2D nmr spectroscopy and its conversion into deoxymethylenelycoctonine. © 1993.