1H-Indole-2,3-dione 2,3-Diketoindoline 2,3-Dioxo-2,3-dihydroindole 2,3-Dioxoindoline 2,3-Indolinedione 2,3-Ketoindoline 91-56-5 Indole-2,3-dione Isatic acid lactam Isatin Isatine Isatinic acid anhydride Isotin NSC9262 Pseudoisatin WLN: T56 BMVVJ o-Aminobenzoylformic anhydride