However, it can be prepared either from vindoline and catharanthine[7][10] or from leurosine,[11] in both cases by synthesis of anhydrovinblastine, which "can be considered as the key intermediate for the synthesis of vinorelbine."[7] The leurosine pathway uses the Nugent–RajanBabu reagent in a highly chemoselective de-oxygenation of leurosine.[12][11] Anhydrovinblastine is then reacted sequentially with N-bromosuccinimide and trifluoroacetic acid followed by silver tetrafluoroborate to yield vinorelbine.[10]