The first total synthesis of scarce alkaloid indigotinoline A from Isatis indigotica was achieved in six steps from a known carboxylic acid (13% overall yield). The distinctive 6/5/6/5/6 N,O-heterocycle was efficiently assembled via a one-pot triple cascade, Povarov-type cyclization, intramolecular substitution, and visible-light-mediated oxidative rearrangement, followed by bioinspired N-oxidation/1,2-migration. This synthesis also prompted re-examination of proposed biosynthetic precursor isatindigotindoline B, leading to revision of its stereochemistry based on spectroscopic analysis.
Building similarity graph...
Analyzing shared references across papers
Loading...
Jiaji Li
Zhibin Zhao
Peiyuan Yang
Organic Letters
Shenyang Pharmaceutical University
Building similarity graph...
Analyzing shared references across papers
Loading...
Li et al. (Wed,) studied this question.
www.synapsesocial.com/papers/69d896046c1944d70ce072e8 — DOI: https://doi.org/10.1021/acs.orglett.6c01066