From the bulbs and leaves of Hymenocallis expansa (Amaryllidaceae), three alkaloid constituents were identified: (+)-tazettine, (+)-hippeastrine, and (-)-haemanthidine. These alkaloids demonstrated significant cytotoxicity when tested against a panel of human and murine tumor cell lines.
Seven alkaloids were isolated from Sprekelia formosissima, and five from Hymenocallis x festalis. Tazettine, lycorine, haemanthidine and haemanthamine were evaluated for antiproliferative and multidrug resistance (mdr) reversing activity on mouse lymphoma cells. Lycorine, haemanthidine and