Open Analogues of Arcyriaflavin A. Synthesis through Diels−Alder Reaction between Maleimides and 1-Aryl-3-<i>tert</i>-butyldimethylsiloxy-1,3-butadienes

Abstract

The preparation of a range of open analogues of arcyriaflavin A is described. The synthetic approach is based on the use of perhydroisoindole-1,3,5-triones as key intermediates, which were obtained via Diels-Alder methodology using 1-aryl-3-siloxy-1, 3-butadienes as starting materials. Fischer indolization and aromatization processes afforded different methoxy-substituted arylpyrrolocarbazoles. The stereochemistry and conformation of the Diels-Alder products and the regiochemistry of the indolization reactions are supported by NMR and molecular modeling studies.