2-Oxo-2H-1-benzopyran-3,6-dicarboxylic acid 2H-1-BENZOPYRAN-3,6-DICARBOXYLIC ACID, 2-OXO- 3,6-Dicarboxycoumarin 5-18-08-00673 (Beilstein Handbook Reference) 6468-68-4 BRN 1288522 SC-349