Recent Developments in Asymmetric Synthesis of Cyclohepta[b]indole Derivatives

Abstract

Cyclohepta[b]indole derivatives constitute a prominent class of indole‑annulated medium‑sized ring systems that occur in diverse bioactive natural products and pharmaceutically relevant scaffolds. Their enantioselective construction, however, remains intrinsically challenging owing to conformational flexibility, transannular interactions, and unfavorable thermodynamic/entropic features associated with seven‑membered ring formation. This review summarizes progress in emerging asymmetric methodologies that deliver chiral cyclohepta[b]indole frameworks, by highlighting advances in catalyst design, reaction efficiency, and stereocontrol, alongside mechanistic insights that rationalize selectivity trends and guide future development.