Reflexin A, a new indole alkaloid from Rauvolfia reflexa induces apoptosis against colon cancer cells.

One new indole alkaloid, reflexin A (1), and two known indoles, macusine B (2) and vinorine (3), were isolated from the bark of Rauvolfia reflexa. Their structures were elucidated by 1D and 2D NMR, UV, IR, and MS spectroscopic analyses. Compound 1 displayed anticancer activity against HCT-116 colon cancer cells with an IC50 value of 30.24 ± 0.75 µM. The results implied that the newly isolated 1 induced apoptosis in HCT-116 cells, suggesting its possible role as an anticancer agent. In vivo acute toxicity study was performed on compound 1 to evaluate its safety profile.

2-(4-Chloro-phen-yl)-3,5-dimethyl-1λ,2-thia-zine-1,1-dione.

In the title compound, C(12)H(12)ClNO(2)S, the S atom is displaced by 0.708 (2) Šout of the plane through the remaining atoms of the thia-zine ring (r.m.s. deviation = 0.0823 Å). This plane makes a dihedral angle of 89.33 (7)° with the phenyl ring. In the crystal, adjacent mol-ecules are connected through C-H⋯O hydrogen bonds into layers parallel to the bc plane.