The molecule is a tetrapeptide composed of L-alanine, L-phenylalanine, L-threonine, and L-serine joined in sequence by peptide linkages. It has a role as a metabolite. It derives from a L-alanine, a L-phenylalanine, a L-threonine and a L-serine.
(2S)-2-[[(2S,3R)-2-[[(2S)-2-[[(2S)-2-aminopropanoyl]amino]-3-phenylpropanoyl]amino]-3-hydroxybutanoyl]amino]-3-hydroxypropanoic acid