Phenylacetylglycine is an acyl glycine. Acyl glycines are normally minor metabolites of fatty acids. The presence of phenylacetylglycine in urine has been confirmed for dogs rats and mice. However the presence of this compound in human urine is controversial. GC-MS studies have not found this compound while NMR studies claimed to have identified it.

Pimonidazole accumulates in hypoxic cells via covalent binding with macromolecules or by forming reductive metabolites after the reduction of its nitro group.

Succinic acid is a water-soluble, colorless crystal with an acid taste that is used as a chemical intermediate, in medicine, the manufacture of lacquers, and to make perfume esters.