Colochirosides B1, B2, B3 and C, Novel Sulfated Triterpene Glycosides from the Sea Cucumber Colochirus robustus (Cucumariidae, Dendrochirotida).

Four new triterpene glycosides, colochirosides B1 (1), B2 (2), B3 (3) and C (4) have been isolated from the sea cucumber Colochirus robustus (Cucumariidae, Dendrochirotida). Six known earlier glycosides from representatives of two families of the order Dendrochirotida have also been found in C. robustus. Structures of the glycosides have been elucidated by 2D NMR spectroscopy and mass spectrometry. All the glycosides belong to the holostane series and contain tetrasaccharide linear carbohydrate chains with one or two sulfate groups. Cytotoxic activities of glycosides 1-4 against the ascite form of mouse Ehrlich carcinoma cells and hemolytic activities against mouse erythrocytes have been studied. Hemolytic activity of the glycosides was higher than cytotoxic. Glycosides 3 and 4 demonstrated strong effects, whereas compounds 1 and 2 containing the hydroxy-group in the side chains showed moderate hemolytic activity and were not cytotoxic.