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.

中文翻译：

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Reflexin A，一种来自Rauvolfia reflexa的新的吲哚生物碱诱导针对结肠癌细胞的凋亡。

从Rauvolfia reflexa的树皮中分离出一种新的吲哚生物碱，反射蛋白A（1）和两种已知的吲哚，Macusine B（2）和长春花碱（3）。通过1D和2D NMR，UV，IR和MS光谱分析阐明了它们的结构。化合物1对HCT-116结肠癌细胞显示出抗癌活性，IC50值为30.24±0.75 µM。结果表明，新分离的1诱导HCT-116细胞凋亡，提示其可能作为抗癌药。对化合物1进行了体内急性毒性研究，以评估其安全性。