surprising rearrangement was observed during the reaction of securinine with tribromo-isocyanuric acid or 1,3-dibromo-5,5-dimethylhydantoin in methanol, yielding a stereoselective ringcontraction norsecurinine derivative. Meanwhile two oxidation rearrangement products were also reported. Some preliminary discussions on the reactivity of securinine were conducted from these rearrangements; it is believed