A synthetic study toward the structurally complex rearranged-type C-19-diterpenoid alkaloids leading to construction of the strained 6/3/5/6 tetracyclic core is presented. The synthesis features an intramolecular Diels-Alder cycloaddition reaction to assemble the highly substituted central cyclopropane motif, which may serve as a key strategy for the total synthesis of relevant natural product molecules. (C) 2020 Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences. Published by Elsevier B.V. All rights reserved.