The molecule is a peptide anion arising from deprotonation of the three carboxy groups and protonation of the primary amino group of D-gamma-glutamyl-D-glutamic acid. It is a conjugate base of a D-gamma-glutamyl-D-glutamic acid.
(2R)-2-[[(4R)-4-azaniumyl-4-carboxylatobutanoyl]amino]pentanedioate