Triterpenoids From the Leaves of Carissa carandas With Their Cytotoxicities on Cancer Cells.

Previous studies on Carissa carandas have demonstrated that C. carandas contains various triterpenoids exhibiting significant cytotoxic activities against cancer cells. In the current study, two novel pentacyclic triterpenoids (1 and 2), together with six known triterpenoids (3-8), were isolated from the leaves of C. carandas. The structures of these new compounds were unequivocally elucidated by high-resolution electrospray ionization mass spectrometry and one-/two-dimensional nuclear magnetic resonance data. All the isolates were evaluated for their cytotoxic effects against four cancer cell lines, including CNE1, CNE2, HONE-1, and CAL27. Among them, compound 1 was found to display significant cytotoxicity toward CNE1 and HONE-1 cancer cells with IC50 values of 5.31 ± 0.71 and 3.87 ± 0.35 µM, respectively.