Previous communications (1,2) from this laboratory have described the isolation and characterization of three novel and six known diterpenoid alkaloids from the roots of the Chinese larkspur, Delphinium tatsienense Franch. Among the new alkaloids, the structure of tatsinine (1) was deduced from biogenetic considerations and elaborate spectral analysis and is particularly interesting. Tatsinine (1) is very polar and possesses a series of four vicinal hydroxyl groups, as well as a fifth, isolated hydroxy group. © 1986, American Chemical Society. All rights reserved.