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In 2006,a new member of gelsemium alkaloids named Gelsedilam (1) was isolated from the leaves of Gelsemium Eiegans Benth by Takayama and coworkers.1 It belongs to the gelsedine-type alkaloids and features a compact and strained core structure in combination with an all-carbon quaternary center of the spiro-N-methoxy indolinone and an intricate cyclic system.2 The first total synthesis of gelsedilam,which features a highly diastereoselective thia-Michael-intramolecular aldol reaction to install the strained and caged[3.2.2]bridged ring system and highly efficient NiCl2/NaBI--mediated four-step transformation m one-pot to construct its five-membered lactam ring is reported.The synthesis requires only 18 linear steps from the known compounds,providing useful strategies for the construction of the intricate ring system in the synthesis of related gelsedine-type alkaloids.