Novel steroidal saponins from Liriope graminifolia (Linn.) Baker with anti-tumor activities

Phytochemical investigation of the underground parts of Liriope graminifolia (Linn.) Baker resulted in the isolation of two new steroidal saponins lirigramosides A (1) and B (2) along with four known compounds. The structures were determined by extensive spectral analysis, including two-dimensional (2D) NMR spectroscopy and chemical methods, to be 3-O-{beta-D-xylopyranosyl-(1 -> 3)-alpha-L-arabinopyranosyl-( 1 -> 2)-[alpha-L-rhamnopyranosyl-(1 -> 4)]-beta-D-glucopyranosyl-(25S)-spirost-5-ene-3 beta, 17 alpha-diol (1), 1-O-[alpha-L-rhamnopyranosyl-(1 -> 2)-beta-D-xylopyranosyl]-(25R)-ruscogenin (2), 1-O-beta-D-xylopyranosyl-3-O-alpha-L-rhamnopyranosyl-(25S)-ruscogenin (3), 3-O-alpha-L-rhamnopyranosyl-1-O-sulfo-(25S)-ruscogenin (4), methylophiopogonanone B (5), and 5,7-dihydroxy-3-(4-methoxybenzyl)-6-methyl-chroman-4-one, (ophiopogonanone B, 6), respectively. Compound 1 has a new (25S)-spirost-5-ene-3 beta, 17 alpha-diol ((25S)-pennogenin) aglycone moiety. The isolated compounds were evaluated for their cytotoxic activities against Hela and SMMC-7721 cells. (C) 2010 Elsevier Ltd. All rights reserved.