Five new triterpenoid saponins from the kernels of Momordica cochinchinensis

Five saponins were isolated from the kernels of Momordica cochinchinensis, by macroporous resin, silica gel, ODS column chromatography, and semi preparative HPLC. Based on MS and NMR analysis, combining with alkaline hydrolysis and acid hydrolysis, their structures were identified as: gypsogenin-3-O-β-D-galactopyranosyl (1→2)-α-L-rhamnopyranosyl (1→3)-β-D-glucuropyranonosyl-28-O-β-D-xylopyranosyl (1→3)-β-D-xylopyranosyl (1→4)-α-L-rhamnopyranosyl (1→2)-β-D-fucopyranoside (1), quillaic acid-3-O-β-D-galactopyranosyl (1→2)-α-L-rhamnopyranosyl (1→3)-β-D-glucuropyranonosyl-28-O-β-D-xylopyranosyl (1→3)-β-D-xylopyranosyl (1→4)-α-L-rhamnopyranosyl (1→2)-β-D-fucopyranoside (2), gypsogenin-3-O-β-D-galactopyranosyl (1→2)-α-L-rhamnopyranosyl (1→3)-β-D-glucuropyranonoside sodium (3), quillaic acid-3-O-β-D-galactopyranosyl (1→2)-α-L-rhamnopyranosyl (1→3)-β-D-glucuropyranonoside sodium (4), 18α-quillaic acid-3-O-β-D-galactopyranosyl (1→2)-α-L-rhamnopyranosyl (1→3)-β-D-glucuropyranonoside (5). Compounds 1-5 were new compounds, and named as mubezhisides A, B, C, D, E, respectively. They all could obviously inhibited the growth of Candida albicans, C. parapsilosis, and C. tropicalis.