Studies on terpenoids and steroids - 18 balaenonol, balaenol and isobalaendiol: Three new 14(15)-ene-quinone-methide triterpenoids from cassine balae

The three new 14(15)-ene-quinone-methide triterpenoids, balaenonol, balaenol and isobalaendiol, isolated from Cassine balae have been shown to be 3,21β-dihydroxy-2,22-dioxo-3,5,7,10(1),14(15)-pentaen-(14→15)-D:A-friedo-24,29-dinoroleanane (1), 3,21β-dihydroxy-2-oxo-3,5,7,10(1),14(15)-pentaen-(14→15)-D:A-friedo-24,29-dinoroleanane (2) and 3,21β,22β-trihydroxy-2-oxo-3,5,7,10(1),14(15)-pentaen-(14→15)-D:A-friedo-24,30-dinoroleanane (3), respectively, on the basis of spectroscopic evidence. The possible biosynthetic origin of these 14(15)-ene-quinone-methides from pristimerin is discussed.