Bufadienolides from Urginea maritima from Egypt

Forty-one bufadienolides were isolated from the bulbs of Urginea maritima agg. from Egypt; 26 of them are new natural compounds. Structure elucidation was performed by comparison with authentic substances or by means of 1H, 13C NMR and FAB mass spectroscopy. Sixteen of the glycosides derive from nine structurally new aglycones: 16 beta-hydroxy-scillarenin, 16 beta-O-acetyl- scillarenin, 12 beta-hydroxy-5 alpha-4,5-dihydro-scillirosidin, 16 beta- hydroxy-5 alpha-4,5-dihydro-scillirosidin, 16 beta-O-acetyl-5 alpha-4,5- dihydro-scillirosidin, 12 beta-hydroxy-scillirubrosidin, 16 beta-O-acetyl- scillirubrosidin, 9-hydroxy-scilliphaeosidine and 12 beta-hydroxy-desacetyl- scillirosidine.