Eight new steroidal glycosides were isolated from the starfish H. regularis. Three compds. contain the 2,4-di-O-methyl-β-D-xylopyranosyl-(1→2)-α-L-arabinofuranosyl disaccharide moiety, which is attached at C-24 of polyhydroxysteroid aglycons. Another 3 glycosides have polyhydroxylated 24-(β-hydroxyethyl) steroid aglycons with the disaccharide moieties, 2-O-methyl-β-D-xylopyranosyl-(1→2)-β-D-xylopyranosyl or 2,4-di-O-methyl-β-D-xylopyranosyl-(1→2)-α-L-arabinofuranosyl, located at the primary hydroxyl group at C-29. Unlike the other compds., the other 2 glycosides have a sulfate group. These glycosides are accompanied by 2 nonglycosidated polyhydoxylated sterols, i.e., (25S)-5α-cholestane-3β,6α,8,15β,26-hexol and (25S)-5α-cholestane-3β,4β,6α,8,15β,26-heptol. The structures of the new metabolites were detd. by interpretation of spectral data, comparison with related glycosides described previously, and chem. transformations.
STARFISH SAPONINS .23. STEROIDAL GLYCOSIDES FROM THE STARFISH HALITYLE-REGULARIS
RICCIO, Raffaele;
1986-01-01
Abstract
Eight new steroidal glycosides were isolated from the starfish H. regularis. Three compds. contain the 2,4-di-O-methyl-β-D-xylopyranosyl-(1→2)-α-L-arabinofuranosyl disaccharide moiety, which is attached at C-24 of polyhydroxysteroid aglycons. Another 3 glycosides have polyhydroxylated 24-(β-hydroxyethyl) steroid aglycons with the disaccharide moieties, 2-O-methyl-β-D-xylopyranosyl-(1→2)-β-D-xylopyranosyl or 2,4-di-O-methyl-β-D-xylopyranosyl-(1→2)-α-L-arabinofuranosyl, located at the primary hydroxyl group at C-29. Unlike the other compds., the other 2 glycosides have a sulfate group. These glycosides are accompanied by 2 nonglycosidated polyhydoxylated sterols, i.e., (25S)-5α-cholestane-3β,6α,8,15β,26-hexol and (25S)-5α-cholestane-3β,4β,6α,8,15β,26-heptol. The structures of the new metabolites were detd. by interpretation of spectral data, comparison with related glycosides described previously, and chem. transformations.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
