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Two new steroid glycosides were isolated from the Far East starfish Hippasteria kurilensis collected in the Sea of Okhotsk. They were characterized as (22E,24R)-3-O-(2-O-methyl-beta-D-xylopyranosyl)-24-O-[2-O-methyl-beta-D-xylopyranosyl-(1-->5)-alpha-L-arabinofuranosyl]-5alpha-cholest-22-ene-3beta,4beta,6alpha,7alpha,8,15beta,24-heptaol (kurilensosid I) and (24S)-3-O-(2-O-methyl-beta-D-xylopyranosyl)-24-O-(alpha-L-arabinofuranosyl)-5alpha-cholestan-3beta,4beta,6beta,15alpha,24-pentaol (kurilensosid J). In addition, the earlier known glycosides linkosides F and L1, levisculoside G, forbeside L, desulfated echinasteroside A, and granulatoside A were isolated and identified. The structures of the new compounds were established with the help of bidimentional NMR spectroscopy and mass spectrometry.

Three novel steroidal triglycosides, designated as kurilensosides A, B, and C (1- 3), were isolated along with a new steroidal diglycoside, kurilensoside D (4), and two new (6, 7) and one known (5) polyhydroxysteroid from the alcoholic extract of the Far Eastern starfish Hippasteria kurilensis. Compounds 1-3 are the first triglycosides containing two carbohydrate chains found from starfish. The structures of 1-7 were elucidated by spectroscopic methods (mainly 2D NMR) and chemical derivatization. Glycosides 1-4 and steroids 6 and 7 inhibited sea urchin egg fertilization by sperm preincubated with these compounds.

Six new natural compounds were isolated from two Far Eastern starfish species, Henricia aspera and H. tumida, collected in the Sea of Okhotsk. Two new glycosylated steroid polyols were obtained from H. aspera: asperoside A and asperoside B, which were shown to be (20R,24R,25S)-3-O-(2,3-di-O-methyl-beta-D-xylopyranosyl)-24-methyl-5alpha-cholest-4-ene-3beta,6beta,8,15a,16beta,26-hexaol and (20R,24R,25S,22E)-3-O-(2,4-di-O-methyl-beta-D-xylopyranosyl)-24-methyl-5alpha-cholest-22-ene-3beta,4beta,6beta,8,15alpha,26-hexaol, respectively. Two other glycosylated polyols, tumidoside A, with the structure elucidated as (20R,22E)-3-O-(2,4-di-O-methyl-beta-D-xylopyranosyl)-26,27-di-nor-24-methyl-5alpha-cholest-22-ene-3beta,4beta,6beta,8,15alpha,25-hexaol, and tumidoside B, whose structure was elucidated as (20R,24S)-3-O-(2,3-di-O-methyl-beta-D-xylopyranosyl)-5alpha-cholestan-3beta,4beta,6beta,8,15alpha,24-hexaol, were isolated from the two starfish species. (20R,24S)-Salpha-Cholestan-3beta,6beta,15alpha,24-tetraol and (20R,24S)-5alpha-cholestan-3beta,6beta,8,15alpha,24-pentaol were identified only in H. tumida. The known monoglycosides henricioside H1 and laeviuscolosides H and G were also identified in both species.

A reinvestigation of the polar steroid fraction from the starfish Aphelasterias japonica, collected near the Russian shore of the Sea of Japan, has afforded two new compounds, the disulfated quinovoside aphelasteroside C (1) and the monosulfated polyhydroxysteroid aphelaketotriol (2). Compounds 1 and 2 contain a unique 23-oxo-24-hydroxylated side chain that is unprecedented in marine steroids. The known compounds cheliferoside L1 (3), 3-O-sulfoasterone (4), forbeside E3 (5), and 3-O-sulfothornasterol A (6) were also isolated from this source. Compounds 1-3, 5, and 6 showed hemolytic activity to mouse erythrocytes.