A new cytotoxic indole alkaloid from Tabernaemontana inconspicua stapf

Abstract

One new indole alkaloid derivative, 5,6-dioxo-11-hydroxy voacangine (1) together with four known compounds (2-5), were isolated from the fruits of Tabernaemontana inconspicua Stapf (Apocynaceae). Their structures were determined using 1D and 2D NMR, HRESI-MS, and a comparison with the literature. The new compound was found to be cytotoxic on human breast cancer MDA-MB 231 cells with IC₅₀ values of 3.35 µM and 2.19 µM after 24 and 48 hours, respectively.

GRAPHICAL ABSTRACT

Keywords:

• Tabernaemontana inconspicua
• indole alkaloids
• cytotoxic activity

Acknowledgements

EMN is very grateful to Chinese Academy of Sciences President’s International Fellowship Initiative for its financial support. We thank Prof. Dr. Dr. h.c. Michael Spiteller and Pr. Marie-Christine Lallemand for performing NMR analyses.

Disclosure statement

No potential conflict of interest was reported by the authors.