A phytochemical study on the stems and leaves of Tabernaemontana bovina led to the isolation and identification of a new monoterpenoid indole alkaloid, taberboviline (1), together with seven known monoterpenoid indole alkaloids (2-8). The chemical structure of 1 was elucidated on the basis of extensive spectral data analyses and the known compounds were identified by comparing their experimental spectral data with the reported data in the literature. All isolated indole alkaloids were evaluated for their antiproliferative activities against five human cancer cell lines in vitro. Monoterpenoid indole alkaloids 1-8 exhibited notable antiproliferative activities against five human cancer cell lines with IC50 values ranging from 0.58 ± 0.05 to 26.19 ± 0.16 μM.
Keywords: Apocynaceae; T. bovina; antiproliferative activities; monoterpenoid indole alkaloid; taberboviline.