Reaction of (6-hydroxy-3-sulfoquinolin-7 -yloxy ) acetic, (5-chloro-6-hydroxy-3-sulfoquinolin-7 -yloxyl) acetic, (5-bromo-6-hydroxy-3-sulfoquinolin-7-yloxy) acetic acids with nitric acid afforded a new quinoline quinone, 7(Carboxymethoxy)-3-sulfoquinoline-5,6-dione, which is readily reduced by H2N-OH, H2N-NH2, H2NNH-Ph and EtOH to give 7-(carboxymethoxy)-3-sulfoquinoline-5,6-diol. The structure of the obtained compounds was determined by elemental analysis, IR, ESI MS, 1D NMR and 2D NMR spectroscopy methods.