Abstract
Two new monosulfated triterpene glycosides, magnumosides B3 (1) and B4 (2) and one new disulfated triterpene glycoside, magnumoside C3 (3) have been isolated from the tropical Indo-West Pacific sea cucumber Neothynidium (=Massinium) magnum (Phyllophoridae, Dendrochirotida) collected in the Vietnamese shallow waters. The structures of the glycosides were elucidated by 2D NMR spectroscopy and mass-spectrometry. All the isolated glycosides are characterized by the non-holostane type aglycones having 18(16)-lactone and 7(8)-double bond and differing from each other by the side chains structures and the quantity of sulfate groups in the carbohydrate chains. The cytotoxic activity of the compounds 1–3 against mouse spleen lymphocytes and ascite form of mouse Ehrlich carcinoma cells, human colorectal carcinoma DLD-1 as well as their hemolytic effects have been studied. Magnumoside B4 (2) greatly suppressed the colony formation and decreased the size of colonies of DLD-1 cancer cells at non-cytotoxic concentrations. The study on synergism of effects of radiation and compounds 1–3 on proliferation of DLD-1 cells showed that the tested compounds almost equally enhanced antiproliferative effect of radioactive irradiation.