Visible-light-induced annulation of 4-aminocoumarins to tetrahydropyrimidine-fused coumarins and evaluation of their antitumor activities

A green and efficient synthetic route to novel tetrahydropyrimidine-fused coumarins has been established via a visible-light-induced multicomponent reaction of 4-aminocoumarins, N -arylglycines, and formaldehyde without exogenous photosensitizers.