N8-Acetylspermidine dihydrochloride is a polyamine that regulates ischemic cardiac apoptosis and resultant cardiac dysfunction.

N-Alpha-acetyllysine is a N-acetylated amino acid. It is a normal constituent of human urine with concentrations in normal samples too small to allow its routine detection; however it has been found at increased levels in the urine of a patient with aminoacylase I deficiency.

3-Hydroxybutyric acid (or beta-hydroxybutyrate) is a ketone body. Like the other ketone bodies (acetoacetate and acetone) levels of 3-hydroxybutyrate in blood and urine are raised in ketosis. In humans 3-hydroxybutyrate is synthesized in the liver from acetyl-CoA and can be used as an energy source by the brain when blood glucose is low.