Synthesis of furo[3,2-c]coumarin derivatives using visible-light-promoted radical alkyne insertion with bromocoumarinsElectronic supplementary information (ESI) available: Full experimental procedures and characterization data for all the compounds. See DOI: 10.1039/c6ob00768f

The synthesis of privileged structures, which are potent drug candidates, is an impetus for drug discovery. The construction of heterocyclic framework furo[3,2- c ]coumarins using a visible-light promoted photoredox neutral coupling of 3-bromo-4-hydroxycoumarins with commercially available alkynes has been reported. These reactions can be carried out at room temperature under visible light irradiation with good chemical yields. This work presents 17 furocoumarins, 12 of which are new. Three of the newly synthesized compounds show potent cytotoxicity, and one shows moderate acetylcholinesterase inhibitory activity with IC 50 values of 2.16 ± 0.13 μM. Heterocyclic framework furo[3,2- c ]coumarins were constructed using a visible-light promoted photoredox neutral coupling of 3-bromo-4-hydroxycoumarins with commercially available alkynes.