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Isatin or 1H-indole-2,3-dione is an indole derivative.
I 1517 (OTTO) Isatin, GR 99%+ Cas no 91-56-5 - used in the syntheses of pirquinozol, talnetant, tacrine, dibucaine, ciclazindol, and methisazone, and also for Oxyphenisatin.