Total synthesis of the antitumor active pyrrolo[2,1-a]isoquinoline alkaloid (±)-crispine A

Addition of a propargyl Grignard reagent to 3,4-dihydro-6,7-dimethoxyisoquinoline, silver(I)-promoted oxidative cyclization, and chemoselective hydrogenation of the pyrrole ring provide a simple three-step route to the antitumor active pyrrolo[2,1-a]isoquinoline alkaloid (±)-crispine A.