The molecule is an L-alpha-amino acid zwitterion that is 2'-alpha-mannosyl-L-tryptophan in which a proton has been transferred from the carboxy group to the amino group. It is the major species at pH 7.3. It is a tautomer of a 2'-alpha-mannosyl-L-tryptophan.
(2S)-2-azaniumyl-3-[2-[(2R,3S,4R,5S,6R)-3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]-1H-indol-3-yl]propanoate