Furostanol oligoglycosides fromAsparagus cochinchinensis

Three new furostanol oligoglycosides, named aspacochioside A (1), B (2) and C (3), together with the known compound 3-O-[(alpha-L-rhamnopyranosyl-(1 --> 4))(beta-D-glucopyranosyl)]-26-O[beta-D-glucopyranosyl]-(25S)-5beta-spirostane-3beta-ol were isolated from the roots of Asparagus cochinchinensis. Their structures were elucidated by spectroscopic techniques (IR, HR-ESIMS, ESIMS/MS, ID and 2D NMR) and chemical methods as 3-O-[(alpha-L-rhamnopyranosyl-(1 --> 4))(beta-D-glucopyranosyl)]-26-O-[beta-D-glucopyranosyl]-(25S)-5beta-furostane-3beta,22alpha,26-triol (1), 3-O-[(alpha-L-rhamnopyranosyl-(1 --> 4))(beta-D-glucopyranosyl)]-26-O-[beta-D-glucopyranosyl]-22alpha-methoxy-(25S)-5beta-furostane-3beta,26-diol (2), and 3-O-[(alpha-L-rhamnopyranosyl-(1 --> 4))(beta-D-glucopyranosyl)]-26-O-[beta-D-glucopyranosyl]-(25S)-5beta-furost-20(22)-en-3beta,26-diol (3).