Synthesis and properties of 2-cyanoethoxy derivatives of dammarane triterpenoids

Cyanoethylation of dammaran-3β-ols and 3-oxime dammarene, semisynthetic derivatives of the natural dipterocarpol, afforded a series of new dammarane triterpenoids containing 2-cyanoethoxy fragment at the carbon atom in the position 3 of the tetracyclic scaffold. A notable antiviral activity was found in 20(S)-3-[(2-cyanoethoxy)imino]-dammar-24-en-20-ol and 20(S)-3-О-(2-cyanoethyl)-25,26,27-trinor-20,24-olidedammarane.