The molecule is a peptide anion that is the conjugate base of gamma-Glu-Trp, obtained by removal of protons from the two carboxy groups as well as protonation of the amino group; major species at pH 7.3. It is a conjugate base of a gamma-Glu-Trp.
(2S)-2-azaniumyl-5-[[(1S)-1-carboxylato-2-(1H-indol-3-yl)ethyl]amino]-5-oxopentanoate