A new piperidine alkaloid from the leaves of <i>Microcos paniculata</i> L.

<p>A new piperidine alkaloid, microcosamine C (<b>1</b>), and one known compound, microcosamine A (<b>2</b>) were isolated from the leaves of <i>Microcos paniculata</i>. Structure elucidation was carried out using HR-ESI-MS, 1D and 2D NMR spectroscopic methods and by comparison with data reported in the literature. The absolute configuration at the C-3 hydroxy group of <b>1</b> was established by a Mosher esterification procedure. Both the isolates (<b>1</b>–<b>2</b>) were evaluated for cytotoxicity against four selected tumour cell lines and showed only weak activity against RAW 264.7 cell line.</p>