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We report here aconcise,collective,and asymmetric total synthesis of sarpagine alkaloids and biogenetically related koumine alkaloids,w hichs tructurally feature ar igid cage scaffold, with l-tryptophan as the starting material. Tw ok ey bridged skeleton-forming reactions,namely tandem sequential oxidative cyclopropanol ring-opening cyclization and ketone a-allenylation, ensure concurrent assembly of the caged sarpagine scaffold and installation of requisite derivative handles.W ith ac ommon caged intermediate as the branch point, by taking advantage of ketone and allene groups therein, total synthesis of five sarpagine alkaloids (affinisine,n ormacusine B, trinervine,N a -methyl-16-epipericyclivine,a nd vellosimine) with various substituents and three koumine alkaloids (koumine,k oumimine,a nd N-demethylkoumine)w ith more complex cage scaffolds has been accomplished.

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