The molecule is an L-alpha-amino acid zwitterion obtained by transfer of a proton from the carboxy to the amino group of L-tryptophan; major species at pH 7.3. It is a tryptophan zwitterion and a L-alpha-amino acid zwitterion. It is a tautomer of a L-tryptophan.
(2S)-2-azaniumyl-3-(1H-indol-3-yl)propanoate