Prolylleucine is a dipeptide containing branched-chain amino acids.

D-Saccharic acid potassium salt is a compound formed from oxidizing sugars which can be used to test for the presence of hepatic enzyme induction. Studies indicate that D-glucuronolactone dehydrogenase oxidizes D-Saccharic acid potassium salt into D-glucaro-l4;63-dilactone.

IRBP (1-20), human is the 1-20 fragment of interphotoreceptor retinoid binding protein (IRBP).This peptide is a 1 to 20 amino acid fragment of the interphotoreceptor retinoid binding protein (IRBP). IRBP is a 140-kDa glycolipoprotein residing in the interphotoreceptor matrix between the neural retina and the retinal pigment epithelium.