de Andrade_2012_J.Pharm.Biomed.Anal_70_13

Plants of the Amaryllidaceae family are a well-known source of tetrahydroisoquinoline alkaloids with a wide range of biological activities including antiviral antitumoral antiparasitic psychopharmacological and acetylcholinesterase inhibitory among others Recent advances in the use of GC or LC coupled to MS have allowed a chemically guided isolation of uncommon and bioactive alkaloids In the present work analytical methods were applied to study the alkaloid profile of Narcissus broussonetii a plant endemic to North Africa Using the GC-MS technique and an in-home mass fragmentation database twenty-three alkaloids were identified including the very rare dinitrogenous alkaloids obliquine plicamine and secoplicamine Applying LC-ESI-LTQ-Orbitrap-MS fragmentation profiles were found to be similar for obliquine and plicamine but different for secoplicamine Pretazettine a potent cytotoxic alkaloid was also isolated from N broussonetii although its identification by GC-MS was only possible after a BSTFA-derivatization The silylated crude methanolic extract only showed the presence of pretazettine-TMS confirming that tazettine was formed after the alkaloid extraction The same observation was made in Narcissus cultivars in which tazettine had been detected as the major alkaloid As part of an ongoing project on MS of Amaryllidaceae alkaloids the silylated tazettine and pretazettine were studied by GC-MS/MS and found to differ in their fragmentation routes Finally the EtOAc extract of N broussonetii showed notable in vitro activity against Trypanosoma cruzi with an IC(50 value of 1.77mug/ml.