Furostane-Type Steroidal Saponins from the Roots of Chlorophytum borivilianum

Four new furostanol steroid saponins, borivilianosides A–D (1–4, resp.), corresponding to (3β,5α,22R,25R)-26-(β-D-glucopyranosyloxy)-22-hydroxyfurostan-3-yl O-β-D-xylopyranosyl-(13)-O-β-D-glucopyranosyl-(14)-O-[α-L-rhamnopyranosyl-(12)]-β-D-galactopyranoside (1), (3β,5α,22R,25R)- 26-(β-D-glucopyranosyloxy)-22-methoxyfurostan-3-yl O-β-D-xylopyranosyl-(13)-O-β-D-glucopyranosyl-(14)-O-[α-L-rhamnopyranosyl-(12)]-β-D-galactopyranoside (2), (3β,5α,22R,25R)-26-(β-D-glucopyranosyloxy)-22-methoxyfurostan-3-yl O-β-D-xylopyranosyl-(13)-O-[β-D-glucopyranosyl-(12)]-O-β-D-glucopyranosyl-(14)-β-D-galactopyranoside (3), and (3β,5α,25R)-26-(β-D-glucopyranosyloxy)furost-20(22)-en-3-yl O-β-D-xylopyranosyl-(13)-O-[β-D-glucopyranosyl-(12)]-O-β-D-glucopyranosyl-(14)-β-D-galactopyranoside (4), together with the known tribuluside A and (3β,5α,22R,25R)-26-(β-D-glucopyranosyloxy)-22-methoxyfurostan-3-yl O-β-D-xylopyranosyl-(12)-O-[β-D-xylopyranosyl-(13)]-O-β-D-glucopyranosyl-(14)-O-[α-L-rhamnopyranosyl-(12)]-β-D-galactopyranoside were isolated from the dried roots of Chlorophytum borivilianumSant and Fern. Their structures were elucidated by 2D-NMR analyses (COSY, TOCSY, NOESY, HSQC, and HMBC) and mass spectrometry.