Modular Total Synthesis of Lamellarin G Trimethyl Ether

A modular synthesis of the lamellarin G trimethyl ether has been developed based on the application of several reaction sequences which include Friedel-Crafts acylation, esterification, haloarylation, and oxidative cyclization. The formation of pyrrolo [2,1-a]isoquinoline core, the key step for the successful completion of lamellarin G trimethyl ether synthesis, is comfortably accomplished through the haloarylation of 3-bromo-4-(3,4-dimethoxy-benzoyl)-6,7-dimethoxy-chroman-2-one which has resulted in exclusive endo product.