Herein, we report an efficient synthetic method for constructingthe tetracyclic scaffold of sulfur-containing discorhabdin-type alkaloids.The key to success is the BF3 center dot Et2O-promoteddienone-phenol-type rearrangement/sulfur insertion cascade reaction,which converts the common and readily available N,O-acetal-bridged tetracyclic framework to the labile and syntheticallychallenging N,S-acetal-bridged tetracyclic frameworkin a single step. Additionally, the hypervalent iodine promoted intramolecularoxidative dearomatization terminated with amide and indium-(III) acetate-facilitatedradical cyclization were also essential elements in this study.