Structure and cytotoxicity of steroidal glycosides from Allium schoenoprasum

Abstract A phytochemical analysis of the whole plant of Allium schoenoprasum , has led to the isolation of four spirostane-type glycosides ( 1 – 4 ), and four known steroidal saponins. Their structures were elucidated mainly by 2D NMR spectroscopic analysis and mass spectrometry as (20 S ,25 S )-spirost-5-en-3β,12β,21-triol 3- O -α- l -rhamnopyranosyl-(1 → 2)-β- d -glucopyranoside ( 1 ), (20 S ,25 S )-spirost-5-en-3β,11α,21-triol 3- O -α- l -rhamnopyranosyl-(1 → 2)-β- d -glucopyranoside ( 2 ), laxogenin 3- O -α- l -rhamnopyranosyl-(1 → 2)-[β- d -glucopyranosyl-(1 → 4)]-β- d -glucopyranoside ( 3 ), and (25 R )-5α-spirostan-3β,11α-diol 3- O -β- d -glucopyranosyl-(1 → 3)-[β- d -glucopyranosyl-(1 → 4)]-β- d -galactopyranoside ( 4 ). Four of the isolated compounds were tested for cytotoxic activity against the HCT 116 and HT-29 human colon cancer cell lines.