Progress in the Synthesis of Aspidospermidine

In the field of drug discovery, natural products have consistently served as a crucial treasure trove for new drug leads due to their structural diversity and specific biological activities. Aspidospermidine, belonging to the aspidosperma alkaloid family, features a unique indole-fused pentacyclic scaffold. In recent years, its total synthesis has attracted significant attention and witnessed continuous breakthroughs. This review systematically collates the latest research progress in the synthesis of aspidospermidine, and focuses on an in-depth discussion of the three mainstream synthetic strategies for the construction of its pentacyclic core, namely assembling the C/D/E ring framework from indole precursors, constructing the D/E rings with tetrahydrocarbazole as the key intermediate, and late-stage construction of the indoline ring on a pre-synthesized C/D/E ring framework. It also elaborates in detail on the corresponding core synthetic methods and key technological breakthroughs of each strategy. The aim is to provide insights and references for developing more concise and efficient synthetic routes for aspidospermidine and its analogues.