Eucosterol oligoglycosides isolated from Scilla scilloides and their anti-tumor activity

Two new eucosterol oligoglycosides, 15-deoxo-30-hydroxyeucosterol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-[(beta-D-glucopyranosyl-(1-->3)]-beta-D-glucopyranosyl-(1-->2)-alpha-L-arabinopyranosyl-(1-->6)-beta-D-glucopyranoside (scillanoside L-1, 1) and 3beta,31-dihydroxy-17alpha,23-epoxy-5alpha-lanost-8-en-23,26-olactone 3-O-alpha-L-rhamnopyranosyl-(1-->2)-[beta-D-glucopyranosyl-(1-->3)]-beta-D-glucopyranosyl-(1-->2)-alpha-L-arabinopyranosyl-(1-->6)-beta-D-glucopyranoside (scillanoside L-2, 2), were isolated from the bulbs of Scilla scilloides, together with four that were known (3-6), have been isolated from the bulbs of Scilla scilloides. The structures of the new compounds were determined on the basis of spectroscopic and chromatographic methods, and some chemical transformations were discussed. Amongst the isolated compounds, 3 showed the most significant cytotoxicity against tumor cells tested several types with ED(50) value of 1.53-3.06 nM. In vivo experiments, 3 apparently increased the life span of mice bearing Sarcoma 180 tumor cell with T/C value of 239% at dose of 3 mg/kg.