Synthesis of bis-pyrrole tetra esters and alcohols as novel mimetics of the anticancer mitomycin

Open‐chain bis‐Reissert compounds 1 were converted to the corresponding bis‐oxazolium intermediates via acid‐catalyzed intramolecular cyclization. These oxazolium compounds exist in a variety of tautomeric structures in which the meso‐ionic form can be intercepted by reaction with dipolarophiles in a 1,3‐dipolar‐cycloaddition reaction to produce a variety of highly functionalized bis‐pyrrole esters 2. In turn, the bis‐pyrrole esters could be converted to the corresponding bis‐pyrrole tetrols 3 in high yields. J. Heterocyclic Chem., 2011.