A novel sulfated holostane glycoside from sea cucumber Holothuria leucospilota

A new sulfated holostane glycoside, leucospilotaside B (1), together with the two related structurally known compounds holothurin B(2) (2) and holothurin B (3), was isolated from sea cucumber Holothuria leucospilota collected from the South China Sea. The structure of 1 was elucidated by spectral analysis (1H-, 13C-, and 2D-NMR, ESI-MS, and HR-ESI-MS) and chemical methods. The compounds 1-3 possess the same disaccharide moiety, but were different in the side chains of the triterpene aglycone. Compound 1 showed significant cytotoxicities against four human tumor cell lines, HL-60, MOLT-4, A-549, and BEL-7402.