5,5',6,6'-tetrahydroxy-2,4'-biindolyl

5,6-二羟基吲哚

[2,7'-Bi-1H-indole]-5,5',6,6'-tetrol

4-chloro-pyrrole-2,3,5-tricarboxylic acid

3,5-bis(ethoxycarbonyl)-1H-pyrrole-2-carboxylic acid