Synthesis and fluorescence of anthra[2,3-b]furan-5,10-dione derivatives

4,11-Dialkoxyanthra[2,3-b]furan-5,10-diones containing various substituents in the 3-position were synthesized. Reactions of these compounds with primary and secondary amines resulted in nucleophilic replacement of one or two alkoxy groups by the corresponding amine residues. 4,11-Dialkoxy derivatives of anthra[2,3-b]furan-5,10-dione showed fluorescence with large Stokes shifts (170–200 nm).