Malabaricol is a unique plant natural product, 3-keto tricarbocyclic triterpenoid, isolated from Ailanthus malabarica. Malabaricol underwent reaction with aromatic aldehydes under alkaline conditions to form 2-arylidene analogs. Indoles and pyrazine ring system fused to the 2,3-position of malabaricol were synthesized. In this ring system of tricarbocyclic triterpenoid, the conformation is such that there is no steric hindrance due to C 4 and C 10 axial methyl groups and other skeletons. Malabaricol and its synthetic analogues show cytotoxic activity toward lung cancer, which was compared to that of standard doxorubicin.

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The acetylene derivative Ciryneol C was isolated from the roots of C. japonicum. The asymmetric total synthesis of Ciryneol C was achieved in seven steps, with Horner–Wittig olefination, regioselective epoxide opening, and Cadiot–Chodkiewicz coupling reactions being the key steps.

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