Wiktionary
urocanic acid
n. (context organic compound English) An intermediate in the catabolism of L-histidine, transformed in the liver by urocanate hydratase (or urocanase) into 4-imidazolone-5-propionic acid and subsequently to glutamic acid.
Wikipedia
Urocanic acid
Urocanic acid is an intermediate in the catabolism of L- histidine.