Hippuric acid-15N is the 15N-labeled Hippuric acid. Hippuric Acid (2-Benzamidoacetic acid), an acyl glycine produced by the conjugation of benzoic acid and glycine, is a normal component in urine as a metabolite of aromatic compounds from food.
References
[1] Russak EM, et al. Impact of Deuterium Substitution on the Pharmacokinetics of Pharmaceuticals. Ann Pharmacother. 2019;53(2):211-216. DOI:10.1177/1060028018797110
