Tirucallane triterpenoids from the mastic (Pistacia lentiscus) and their anti-inflammatory and cytotoxic activities

Abstract Phytochemical investigation of mastic, a resin produced by Pistacia lentiscus, led to the isolation and identification of 16 tirucallane triterpenoids, 13 (1–13) of which are undescribed. Their structures and absolute configurations were elucidated based on the analysis of spectroscopic data and single-crystal X-ray diffraction. Compounds 12 and 13 are unusual 7(8 → 9)abeo-tirucallane triterpenoids. Anti-inflammatory assays indicated that compounds 7, 8, 14, and 16 exhibited stronger inhibitory NO production activities (IC50 = 7.7–13.4 μM) than that of the positive control dexamethasone (IC50 = 19.5 μM). In addition, compound 1 showed comparable cytotoxic activity against HepG2 cells to that of doxorubicin (IC50 = 4.92 VS 1.34 μM).