Steroidal saponins from the leaves of Beaucarnea recurvata

Abstract

Thirteen steroidal saponins were isolated from the leaves of Beaucarnea recurvata Lem. Their structures were established using one- and two-dimensional NMR spectroscopy and mass spectrometry. Six of them were identified as: 26- O-β- d-glucopyranosyl (25 S)-furosta-5,20(22)-diene 1β,3β,26-triol 1- O-α- l-rhamnopyranosyl-(1 → 2) β- d-fucopyranoside, 26- O-β- d-glucopyranosyl (25 S)-furosta-5,20(22)-diene 1β,3β,26-triol 1- O-α- l-rhamnopyranosyl-(1 → 2)-4- O-acetyl-β- d-fucopyranoside, 26- O-β- d-glucopyranosyl (25 R)-furosta-5,20(22)-diene-23-one-1β,3β,26-triol 1- O-α- l-rhamnopyranosyl-(1 → 2) β- d-fucopyranoside, 26- O-β- d-glucopyranosyl (25 S)-furosta-5-ene-1β,3β,22α,26-tetrol 1- O-α- l-rhamnopyranosyl-(1 → 4)-6- O-acetyl-β- d-glucopyranoside, 26- O-β- d-glucopyranosyl (25 S)-furosta-5-ene-1β,3β,22α,26-tetrol 1- O-α- l-rhamnopyranosyl-(1 → 2) β- d-fucopyranoside, and 24- O-β- d-glucopyranosyl (25 R)-spirost-5-ene-1β,3β,24-triol 1- O-α- l-rhamnopyranosyl-(1 → 2)-4- O-acetyl-β- d-fucopyranoside. The chemotaxonomic classification of B. recurvata in the family Ruscaceae was discussed.