A novel synthesis of (+)-duocarmycin SA

Article abstract of DOI:10.1016/S0040-4039(97)01716-4

The title synthesis was achieved in eight steps from (S)-5-aminoindoline (S)-4 by a method featuring sequential dehydrogenation, double bond isomerization, and oxidative cyclization of (S)-5-[(1-methoxycarbonylethyl)amino]indoline 5 as the key steps. The sequential reaction was effected by using MnO₂-Pd(OAc)₂ as the oxidizing agent in the presence of an acid catalyst.