Diterpenoids from cascarilla (Croton eluteria Bennet)

Cascarilla is a commercially available and cheap source of polyfunctionalized diterpenoids belonging to the clerodane structural type. In addition to the bitter triol cascarillin, ten further novel diterpenoids (eluterins A-J) have been isolated and characterized by spectroscopic means. Structural diversity within cascarilla clerodanes regards mainly the tether between the carbocyclic and the heterocyclic moieties and the functionalization of C-3, C-4, and C-6 of the decalin core. Cascarillin was shown to be a mixture of interconverting gamma-lactols and not a gamma-hydroxyaldehyde as previously reported