The chemical structures of sarasinosides A₁, A₂, A₃, B₁, B₂, B₃, C₁, C₂, and C₃, nine 30-norlanostane-triterpenoidal oligoglycosides isolated from the Palauan marine sponge Asteropus sarasinosum have been elucidated on the basis of chemical and physicochemical evidence. Sarasinosides A₂ (2) and A₃ (3) were shown to be the 7, 9(11)-diene and 8, 14-diene analogs of sarasinoside A₁ (1), whereas sarasinosides B₂ (7) and B₃ (9) were the 7, 9(11)-diene and 8, 14-diene analogs of sarasinoside B₁ (5), respectively. Similar structural correlations of sarasinosides C₂ (6) and C₃ (8) with sarasinoside C₁ (4) were demonstrated. These sarasinosides characteristically contain one mole each of N-acetyl-glucosamine and N-acetylgalactosamine in their oligosaccharide moieties.