A convergent synthesis of the naturally occurring alkaloid Calothrixin B is presented, which used a regioselective hetero-Diels−Alder reaction between a “push−pull” 2-aza-diene and a N-protected 3-bromo-9H-carbazole-1,4-dione to construct the five-ring skeleton of the molecule. Protection of the indole motif with a benzyl group was unattractive for delivery of sufficient target material because the
High-yielding regioselective synthesis of p-quinone fused 5-substituted-1,4-benzodiazepine scaffolds via Pictet–Spengler type cycloannulation
作者:Ashokkumar Krishnan、Sriraghavan Kamaraj
DOI:10.1039/d4nj00993b
日期:——
We designed a robust and efficient greener synthetic protocol to access p-quinone fused 5-substituted-1,4-benzodiazepine scaffolds, a new molecular hybrid, through InCl3 mediated Pictet–Spengler type cycloannulation of 2-amino-3-arylamino-p-quinone and commercially prevalent aldehydes. This protocol would ease access to privileged redox-active p-quinone fused seven-membered frameworks that are difficult