N idence. In particular elemental analysis and the mass spectrum showed the correct molecular formula and IR and UV spectra confirmed that the compound preserved the anthraquinone structure and the ester group. Full assignement of all protons in the'H NMR spectrum of 2b indicated the presence of aa, B-substituted furan ring fused with the A ring of the anthraquinone since the only aromatic proton in the spectrum resonated as a singlet at ...
![6-methyl-4,8,11-trimethoxyanthra[2,3-b]furan-5,10-dione Structure](https://image.chemsrc.com/caspic/399/110551-55-8.png)