Steroidal oligoglycosides from the seeds of Allium tuberosum

Three new spirostanol steroidal oligoglycosides, together with a known olig oglycoside, were obtained from the seeds of Allium tuberosum after enzymati c hydrolysis of furostanol saponin fraction by beta-glucosidase. On the bas is of spectroscopic analysis, the structure of new spirostanol oligoglycosi des were elucidated as (25S)-spirost-5-ene-2 alpha,3 beta-diol 3-O-alpha-L- rhamnopyranosyl-(1-->4)-[alpha-L-rhamnopyranosyl-(1-->2)]-beta-D-glucopyran oside, (25S)-spirostane-3 beta,5 beta,6 alpha-triol 3-O-alpha-L-rhamnopyran osyl-(1-->4)-beta-D-glucopyranoside, and (25S)-5 beta-spirostane-3 beta,6 a lpha-diol 3-O-alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranoside.