Constituents of holothuroidea, I. Isolation and structures of three triterpenoid aglycones, cucumechinol A, B, and C, from the sea cucumber Cucumaria echinata
Three new holostane2)-type triterpenoid aglycones named cucumechinol A (1), B (2), and C (3) were isolated from the acidic hydrolysate of the crude glycoside mixture prepared from the whole sea cucumber Cucumaria echinata. The structures were identified on the basis of spectral evidence as 3β-hydroxyholost-9(11)-ene-16,23-dione (1), 3β-hydroxyholost-9(11)-en-23-one (2), and 3β-hydroxyholost-8(9)-ene-16,23-dione (3), respectively.