Pseudo Multicomponent Reaction: Synthesis of Fused Pyrano Biscoumarin Analogs from 1,2-diols

Construction of 4-hydroxycoumarin derivatives with adjacent quaternary and tertiary stereocenters via ternary catalysis

4-Hydroxycoumarin derivatives represent one of the most important scaffolds in biologically active substances, pharmaceuticals and functional materials. Herein, we describe an efficient Pd/amine/Brønsted acid ternary-catalytic multicomponent reaction for the rapid construction of substituted 4-hydroxycoumarin derivatives with adjacent quaternary and tertiary stereocenters via convergent assembly of two in situ generated active intermediates. Furthermore, the late-stage transformations of coumarin derivatives and their in vitro trial of antitumor activity successfully demonstrated the potential utilities of the products as platform molecules.

Overview of coumarin-fused-coumarins: synthesis, photophysical properties and their applications

Coumarin-fused-coumarins have attracted significant attention in the scientific world owing to their boundless applications in interdisciplinary areas. Various synthetic pathways have been developed to construct novel coumarin-fused-coumarin analogues by the fusion of modern methodologies with a classical Pechmann reaction or Knoevenagel condensation. Owing to their extended molecular framework, they possess interesting photophysical properties depending on the fused coumarin ring systems. This review highlights previously published reports on the synthetic strategies for structurally diverse coumarin-fused-coumarins. Furthermore, the scope of the synthesized biscoumarin-fused entities is described by highlighting their photophysical properties and applications.