We describe the first total synthesis of the recently discovered pyrano[3,2- a ]carbazole alkaloid clausenalansine A. The synthetic strategy for the construction of this formylpyrano[3,2- a ]carbazole is based on a sequence of Buchwald-Hartwig coupling, palladium(II)-catalyzed oxidative cyclization, Lewis acid promoted annulation of the pyran ring, and chemoselective oxidation of a methyl to a formyl group. © 2020 BMJ Publishing Group. All rights reserved.