An Efficient Approach to the Total Synthesis of Ammosamide B

A new approach for the total synthesis of ammosamide B was realized. The strategy is based on an intermolecular Pd‐catalyzed N ‐arylation of 4‐chloro‐1‐methylindoline‐2,3‐dione ( 2 ), which enables construction of the key pyrroloquinoline skeleton precursor 6 within three steps in an overall yield of 80 %. The ammosamide B total synthesis is achieved in 12 simple transformations by starting from a commercially available starting material and proceeds with an overall yield of 23 %. Additionally, key precursor 6 represents an important intermediate in the synthesis of other pyrroloquinoline‐containing natural products.