Abstract

N‐2‐Nitrophenylsulfenyl imino dipeptides bearing various functional groups were successfully prepared by MnO₂‐mediated oxidation and then subjected to diastereoselective indolylation. Each diastereomer of the adduct was selectively obtained from the same substrates using the appropriate chiral phosphoric acid catalysts. These transformations would be useful for synthesizing non‐canonical amino acid‐containing peptides as novel drug candidates.