Synthesis of 7‐methoxy‐2‐methyl‐3,5,8‐isoquinolinetrione

Synthesis of 7-methoxy-2-methyl-3,5,8-isoquinolinetrione from either 7- or 8-isoquinolinol is described. 3,5,8-Isoquinolinetrione is a novel heteroeyelic quinune which constitutes the aromatic carbon skeleton of mimosamycin.