(-)-Methyl 12-cytisineacetate (2) was isolated from methanol extracts of fresh flowers of Echinosophora koreensis together with seven known lupin alkaloids. Ethyl 12-cytisineacetate (3) was also isolated from ethanol extracts of the same flowers. Compounds 2 and 3 were artifacts and (-)-12-cytisineacetic acid (4) is assumed to be the principal source of 2 and 3. The variations in alkaloid content during growth of the flowers and the seedlings were also examined. © 1985.