Polyhydroxylated steroids glycosides

Vazquez, M. J., Quinoa, E., Riguera, R., San-Martin, A., and Darias, J., Antarctic marine metabolites new polyhydroxylated steroidal glycosides from the starfish Odontaster validus, Liebigs Ann. Chem., 1257, 1993. 

More than one hundred polyhydroxylated steroidal glycosides have been characterized but only few reports on their biological activity have been published. Recently, several examples of new bioactive mono- and diglycosides of polyhydroxysteroids as well as biological studies on known compounds have been reported. 

Much work has been done in the last thirty years on the isolation and structural characterization of saponins and polyhydroxylated steroid glycosides from starfishes and sea cucumbers. The wide spectrum of biological activities these compounds show must be related to their role in the organisms that produce them and this task must be addressed in future investigations. 

Andersson, L., Nasir, A., Bohlin, L., and Ketme, L. (1987b) Studies of Swedish marine organisms. IX. Polyhydroxylated steroidal glycosides from the starfish Porania pulvdlus. J. Nat. Prod., 50,944—947. 

In addition to Asteroidea and Holothuroidea, the phylum Echinodermata (Greek echinos, spiny derma, skin) comprises the classes Ophiuroidea (brittle stars), Crinoidea (sea lilies and feather stars) and Echinoidea (sea urchins). There is no report of occurrence of steroid or triterpenoid glycosides in sea lilies, feather stars or sea urchins. Brittle stars contain sulfated polyhydroxylated steroids [10-12] and only two sulfated steroidal monoglycosides have been isolated from the brittle star Ophioderma longicaudum [13]. 

The starfish Certonardoa semiregularis has shown to be a rich source of bioactive sterols and glycosides of polyhydroxylated steroids. Purification of the brine shrimp active fraction of the methanolic extract of C. semiregularis led to the isolation of nine new sulfated polyhydroxylated steroidal diglycosides [41],... 

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. 

D Auria, M.V., lorizzi, M., Minale, L., Ricdo, R., and Uriarte, E. (1990b) Starfish saponins. Part 41. Structure of two new steroidal glycoside sulfates (miniatosides A and B) and two new polyhydroxylated sterols from the starfish Patiria miniata. J. Nat. Prod., 53, 94-101. 

---