A new alkaloid, K-13, with the composition C21H23O6N, mp 287-288°C, [α]D -420°, has been isolated from the corms of Colchicum kesselringii Rgl. On the basis of UV, IR, NMR, and mass spectroscopy and its conversion into γ-lumicolchicine, the structure of 2-demethyl-γ-lumicolchicine has been proposed for alkaloid K-13. © 1974 Consultants Bureau, a division of Plenum Publishing Corporation.