Cytotoxic triterpene glycosides from the sea cucumber Pseudocolochirus violaceus

A new triterpene glycoside (1) along with the known intercedenside B (2) was isolated from the sea cucumber Pseudocolochirus violaceus. Glycoside 1 was elucidated as 3-O-{6-O-sodiumsulfate-3-O-methyl-β-d-glucopyranosyl-(1 → 3)-β-d-xylopyranosyl-(1 → 4)-[β-d-xylopyranosyl(1 → 2)]-β-d-quinovopyranosyl-(1 → 2)-4-O-sodiumsulfate-β-d-xylopyranosyl}-16β-acetoxy-holosta-7, 24-diene-3β-ol on the basis of extensive spectral studies and chemical evidence. Both the glycosides exhibited significant cytotoxicity against cancer cell lines MKN-45 and HCT-116.