Seven New Noroleanane Triterpenoids from Mastic and Their NO Inhibitory and Cytotoxic Activities.

Mastic is a natural resin produced by Pistacia lentiscus L. (Anacardiaceae) with high medicinal value and have been traditionally used as Uighur imported medicine for centuries. In this study, 16 triterpenoids including seven new noroleanane triterpenoids (1-7), along with nine known oleanane triterpenoids (8-16), were isolated from the mastic. Their chemical structures were determined on the basis of extensive spectroscopic analyses (including IR, UV, ESI-HR-MS and NMR spectroscopy) and singlecrystal X-ray diffraction. Compounds 4-7, 11, 14 and 16 showed strong inhibitory NO production in LPS-induced RAW264.7 cells with IC50 values 7.44-9.76 μM, respectively (positive control dexamethasone, 9.93±1.17 μM). Furthermore, compounds 3 and 12 significantly inhibited the growth of SW480 cells, compound 3 showed the most pronounced inhibitory effect with an IC50 of 2.30±0.38 μM.