Several derivatives of 3,4-diaryl- and 3,4-diindolylpyrrole-2,5-dicarboxylic acids including lycogalic acid A and two Halomonas metabolites were synthesized by oxidative dimerization of arylpyruvic acids or arylpyruvates in the presence of ammonia. The reaction can be applied for a short synthesis of lukianol A.
biomimetic synthesis - pyrroles - lycogalic acid - 3,4-diarylpyrrole-2,5-dicarboxylic acids