As the result of a study of chemical transformations and spectral characteristics, for the new alkaloid karakolidine a lycoctonine skeleton with N-ethyl and C4-methyl groups, hydroxy groups at C1 (α), C8, C10 (α), and C13, and a methoxy group at C15 (β) has been established. Some peculiarities of the fragmentation of derivatives of karakoline and karakolidine under the action of electron impact have been found. © 1976 Plenum Publishing Corporation.