Synthesis of Indole Alkaloids and Alkaloidal Precursors: an Improved Synthesis of Flavopereirine

Abstract

Synthesis of flavopereirine 1, formal synthesis of isogeissoschizines 8 and dihydrocorynantheols 9 through the intermediacy of 3-(2-hydroxyethyl)-6,7-dihydroindolo[2,3-a]quinolizine 3 and also the unexpected formation of the β-carbolines 12 and 13 on Huang–Minlon reaction of 2 are described.

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