N-a-Acetyl-L-arginine also known as N-ac-L-arg-OH or N-alpha-acetylarginine belongs to the class of organic compounds known as n-acyl-l-alpha-amino acids.

5-Methyltetrahydrofolic acid is a biologically active form of folic acid and a methylated derivate of tetrahydrofolate.

It is an isomer of cresotinic acid (2-hydroxy-3-methylbenzoic acid) and oxymethylbenzoic acid (2-methoxybenzoic acid). Derivatives of mandelic acid are formed as a result of metabolism of adrenaline and noradrenaline by monoamine oxidase and catechol-o-methyl transferase.