1H-Indole-2,3-dione, 5,6-dimethyl- (9CI) 5,6-Dimethylindole-2,3-dione 5-21-11-00201 (Beilstein Handbook Reference) 73816-46-3 BRN 0133055 INDOLE-2,3-DIONE, 5,6-DIMETHYL- NSC 104995