Highly hydroxylated steroids of the starfish Archaster typicus from the Vietnamese waters.

Five new steroidal compounds, including an unusual glucoside, along with several known steroids were isolated from the starfish Archaster typicus collected in shallow waters of Quang Ninh province (Vietnam). Three new compounds are 27-nor-cholestane derivatives and the other two are 24,26-dihydroxycholestane derivatives. A biogenesis pathway for the unusual side chain of 27-nor-cholestane derivatives is proposed. Isolated compounds presented moderate toxic effects in the sperm- and 8-blastomere tests on embryonal development of the sea urchin Strongylocentrotusintermedius.