The alkaloid aconitine was oxidized by potassium permanganate in aqueous acetone. It was shown that the oxidation formed three products including the previously described N-de-ethylaconitine, N-de-ethyl-19-oxoaconitine, and a new N-de-ethyl-7,17-secoimino derivative. The structure of the new product was proposed based on spectral data (IR, mass, PMR and 13C NMR spectra). © 2009 Springer Science+Business Media, Inc.