L-alloisoleucine (2S, 3R), a diastereomer of L-isoleucine (2S, 3S), is a normal constituent of human plasma. It was shown, that the plasma L-alloisoleucine above the cutoff value of 5 micromol/L is the most specific and most sensitive diagnostic marker for all forms of maple syrup urine disease (MSUD). The precise mechanism of L-alloisoleucine formation is unclear, but existed suggestions, that R-3-methyl-2-oxopentanoate is an immediate and inevitable byproduct of L-isoleucine transamination and that alloisoleucine is primarily formed via transamination of 3-methyl-2-oxopenanoate in vivo.

Margaric acid (Heptadecanoic acid, C17) is a fatty acid of exogenous (primarily ruminant) origin. Many "odd" length long chain amino acids are derived from the consumption of dairy fats (milk and meat). Heptadecanoic acid constitutes 0.61% of milk fat and 0.83% of ruminant meat fat. The content of heptadecanoic acid in the subcutaneous adipose tissue of humans appears to be a good biological marker of long-term milk fat intake in free-living individuals in populations with high consumption of dairy products. Margaric acid is a metabolite in glutamate and lipid metabolism in vivo. Blood-brain barrier permeable. Orally active. Possibly involved in anti-tumor activity.

Corosolic acid is a pentacyclic triterpene acid isolated from Lagerstroemia speciosa. It inhibits STAT3 and VEGFR2 signaling and has cytotoxic effect on a number of tumor cell lines. Corosolic acid has demonstrated anti-diabetic effect in vivo, probably due to facilitation of GLUT4 translocation or AMPK activation.