Echinaster sepositus

A new type of saponin was discovered as toxic substances in starfishes of the genus Echinaster. The stmcture of steroidal cyclic glycosides, sepositoside A (76) from the Mediterranean starfish Echinaster sepositus [100] was determined. Three major saponins in the same starfish were isolated, and their structures were found to have 22,23-epoxide groups in the side chain [101]. 

Constit. of Echinaster sepositus and Henrida laeviuscola. (3fi,6fi,8p,15a,16fi,22E,24i,25i)-form... 

As the glycosides from starfish are steroidal in nature and as some known polyhydroxylated steroids with moderate cytotoxicity have been isolated from these animals, the literature since 1980 dealing with such compounds will be reviewed here. Aside from some monohydroxyste-rols from Echinaster sepositus 646), Acanthaster planci 647) - this being a source of a new cyclopropane sterol Asterias vulgaris 648), and Comasterias lurida 649), the reports deal mainly with polyhydroxylated steroids. 

De Simone, F., A. Dini, E. Finamore, L. Minale, C. Pizza, R. Riccio, and F. Zollo Starfish Saponins. Part 5. Structure of Sepositoside A, a Novel Steroidal Cyclic Glycoside from the Starfish Echinaster sepositus. J. Chem. Soc., Perkin Trans. 1 1981, 1855. 

Riccio, R., E. de Simone, A. Dini, L. Minale, C. Pizza, F. Senatore, and F. Zollo Starfish Saponins VI - Unique 22,23-Epoxysteroidal Cyclic Glycosides, Minor Constituents from Echinaster sepositus. Tetrahedron Lett. 22,1557 (1981). Erratum Tetrahedron Lett. 22, 2242 (1981). 

Echinasteroside A Echinaster brasiliensis Echinaster sepositus Henricia laeviuscula 4/5 H 3-OH H OH a-0S03Na 3-OH SC-56 G2 lorizzi et al., 1993a... 

Riccio, R., De Simone, E., Dini, A., Minale, L., Pizza, C., Senatore, F., and Zollo, F. (1981) Starfish saponins. VI. Unique 22,23-epoxysteroidal cyclic glycosides, minor constituents from Echinaster sepositus. Tetrahedron Lett., 22, 1557-1560. Erratum Tetrahedron Lett., 22, 2242. 

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