Two new and eleven known norditerpenoid alkaloids from the stems and six known norditerpenoid alkaloids from the leaves have been isolated from Delphinium ajacis. Six alkaloids from the stems and three from the leaves isolated in the present work are new to this plant species. The new alkaloids, 19-oxoanthranoyllycoctonine and 19-oxodelphatine, were assigned the structures 7 and 8, respectively, on the basis of H- and 1 C-nmr spectral data and synthesis. Oxidation of ajacine [9] with OsO4 afforded 19-oxoajacine [10], which was hydro-lyzed to 19-oxoanthranoyllycoctonine [7]. Oxidation of anthranoyllycoctonine {11} with OsO4 also yielded 7. 19-Oxoajacine is a new synthetic alkaloid. © 1991, American Chemical Society. All rights reserved.