Monoterpenoid Quinoline Alkaloids from Stems and Leaves of Melodinus tenuicaudatus

Two previously undescribed monoterpenoid quinoline alkaloids, namely melotenucadines A and B, together with four known analogs, were characterized from the stems and leaves of Melodinus tenuicaudatus. The structures of the new compounds were established by extensive MS and NMR spectroscopic methods, while the absolute configuration was conducted by ECD calculations. Melotenucadine B was found to show certain cytotoxicity to MCF-7 cell (IC50=27.3 mu M).

Automated summary

Two previously unknown monoterpene quinoline alkaloids, melotenucadines A and B, along with four known analogs, were isolated from the stems and leaves of Melodinus tenuicaudatus. The structures of the new compounds were determined using extensive MS and NMR spectroscopic methods, and the absolute configuration was established through ECD calculations. Melotenucadine B exhibited cytotoxicity against MCF-7 cells (IC50=27.3 μM).