Abstract 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.