Isonicotinic acid is a metabolite of isoniazid.

Lithocholic acid is a toxic secondary bile acid, causes intrahepatic cholestasis, has tumor-promoting activity, its toxic effect can be protected after it activates the vitamin D receptor, PXR and FXR.

Adapalene is a dual RAR and RXR agonist, used in the treatment of acne.

Enoxolone is a pentacyclic triterpenoid aglycone metabolite of glycyrrhizin, which is a product of the plant Glycyrrhiza glabra (licorice), with potential expectorant, and gastrokinetic activities.

Baicalein is a CYP2C9 and prolyl endopeptidase inhibitor.

Emodin, a purgative anthraquinone found in several plants, especially Rhamnus frangula, was formerly used as a laxative, but is now used mainly as tool in toxicity studies.

Luteolin is a flavonoid found in Terminalia chebula, which is a non-selective phisphodiesterase PDE inhibitor.

D-Biotin is a water-soluble, enzyme co-factor present in minute amounts in every living cell.