Abstract 1, 6-Dioxapyrene, the first unsubstituted dioxa-analogue of pyrene was synthesized in good yield from 2-carbomethoxy-6-methoxynaphtho [1, 8-bc] pyran in a four-step reaction involving a peri-heterocyclisation. Its 1 H nmr spectral characteristics were compared with those of native pyrene.
![[1]benzopyrano[6,5,4-def][1]benzopyran-2,7-dicarboxylic acid结构式](https://image.chemsrc.com/caspic/373/133345-32-1.png)
