Total synthesis of echinopine A and B have been accomplished, based on a strategy that involved two transition-metal-mediated ene-yne cycloisomerizations. A modified Pd- catalyzed enyne cycloisomerization/intramolecular Diels–Alder cascade rendered a more streamlined synthesis of tricyclic ketone 15, and a Ru-catalyzed ene-yne cycloisomerization/ cyclopropanation resembled the late-stage [5/7]→[3/5/5/7] ring-forming sequence in the ...