3-Hydroxykynurenine (3-hydroxy-DL-Kynurenine) is an active metabolite of tryptophan and inhibits yeast and rat liver aldehyde dehydrogenase by 97 and 69%.

KB-74935 is an enzyme inhibitor and a mineralocorticoid receptor antagonist used to treat cholesterol, hypolipidemia, neurological disorders, and Alzheimer's disease.

Hippuric acid is an acyl glycine formed by the conjugation of benzoic acid with glycine. Hippuric acid is a normal component of urine and is typically increased with increased consumption of phenolic compounds (tea wine fruit juices).