Synthetic Study on Benzocarbolines by Using the Reactivity of Anhydride

Abstract

Benzocarbolines and benzocarbolinones, indoloquinoline alkaloids, have much attention due to their potential effectiveness in medical treatment. Beckmann rearrangement and Schmidt rearrangement are a good method for synthesis of amides from ketones. Albini reported that Beckmann rearrangement of 3-benzoylindole oxime in hot acetic acid gave 3-(benzoylamino)indole as a sole product. However, they did not show the influence of substituents on indole nitrogen and benzene ring about Beckmann rearrangement. Here, we show Beckmann rearrangement of 3-(4-methoxybenzoyl)indole oximes and 5H-indeno[3,2-b]indol-10-one oximes and its application of a synthesis of benzo-β-carbolinones and benzo-γ-carbolinones. In Schmidt rearrangement of 5H-indeno[3,2-b]indol-10-one, 6H-isoindolino[2,1-a]indol-6-one was obtained.

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