Bufadienolides from Drimia macrocentra and Urginea riparia (Hyacinthaceae: Urgineoideae)

Rubellin and riparianin have been isolated from the bulbs of Drimia macrocentra and Urginea riparia (Hyacinthaceae) respectively. Rubellin and riparianin contain a carbohydrate moiety doubly linked to the bufadienolide aglycone at the C-2 and C-3 positions. Riparianin showed moderate activity when tested against MCF7 (breast), TK10 (renal) and UACC62 (melanoma) cancer cell lines.