A Total Synthesis of the Marine Alkaloid Discoipyrrole D.

A total synthesis of the diastereoisomeric pair of compounds, 4, assigned to the marine alkaloid discoipyrrole D is reported. A series of palladium-catalyzed cross-coupling and other reactions was employed to assemble the relevant 1,2,3,4-tetrasubstituted pyrrole (16) that was engaged in MoOPH-mediated oxidative cyclization, then conjugate addition, and redox processes to complete the synthesis. This work serves to confirm the structure (4) originally assigned to discoipyrrole D.