Synthesis of Novel Polycyclic Indole-Annulated Thiopyranocoumarin Derivatives via Domino Knoevenagel–Hetero-Diels–Alder Reaction in Aqueous Media

摘要

An efficient synthesis of polycyclic indole derivatives is achieved via domino Knoevenagel–hetero-Diels–Alder reaction of O-acrylated salicylaldehyde derivatives with dihydroindole-2-thiones in H₂O as solvent. The products are formed in good-to-excellent yields with high regio- and stereoselectivity.