4-Isopropylcatechol is a potent depigmenting agent and is of use in the topical therapy of selected patients with hypermelanosis.

25-Furandicarboxylic acid is a normal urinary metabolite in humans. 25-Furandicarboxylic acid is also a microbial metabolite a product of the oxidation of hydroxymethylfurfural (HMF) by the enzyme furfural/HMF oxidoreductase which is found in the bacterium Cupriavidus basilensis.

Diaziquone (NSC-182986) is a water-soluble synthetic azacyclic benzoquinone that enhances penetration of the blood-brain barrier, has antitumor activity, and is used in the treatment of extreme renal failure.