STRUCTURAL CHARACTERIZATION OF PIPERIDINE ALKALOIDS FROM PANDANUS-AMARYLLIFOLIUS BY INVERSE-DETECTED 2D NMR TECHNIQUES

Three novel piperidine alkaloids were isolated and identified from the leaves of Pandanus amaryllifolius, The structures of pandamarilactone-1, pandamarilactone-32 and pandamarilactone-31 were elucidated using 2D NMR techniques including inverse-detected Heteronuclear Multiple Bond Correlation (HMBC) and Heteronuclear Multiple Quantum Coherence (HMQC) spectroscopy. All of these piperidine alkaloids have a C-9-N-C-9 skeleton and could be derived biogenetically from 4-hydroxy-4-methylglutamic acid.