#chromogen  a compound that can be converted to a pigment
  supertype:  chemical_compound__compound  (chemistry) a substance formed by chemical union of two or more elements or ingredients in definite proportion by weight
  subtype:  urobilinogen__stercobilinogen  a chromogen formed in the intestine from the breakdown of bilirubin; yields urobilins on oxidation; some is excreted in the feces and some is resorbed and excreted in bile or urine

No statement uses or specializes chromogen; click here to add one.