“…There are several reported methods of analysis for swainsonine that include TLC, HPLC, − and MS methods for the direct analysis of the free base alkaloid as well as gas chromatography methods for the analysis of the trimethylsilyl ether or the triacetyl derivatives of swainsonine. − In addition to the occurrence of the free base swainsonine, swainsonine N -oxide, 2 (Figure ), has been reported to occur in several locoweed plants based on isolation and a qualitative TLC method. ,, Qualitative TLC estimates suggested that some locoweeds had similar concentrations of swainsonine and its N -oxide, whereas the N -oxide was not detected by gas chromatography in several Swainsona species tested . Additionally, it has been shown that swainsonine N -oxide was as effective as swainsonine in inhibiting α-mannosidase .…”