The molecule is a non-proteinogenic L-amino acid that is N-acetyl-alpha-D-galactosamine linked via an alpha glycosidic bond to the O at position 3 of L-serine. It is a L-serine derivative and a non-proteinogenic L-alpha-amino acid.
(2S)-3-[(2S,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6-(hydroxymethyl)oxan-2-yl]oxy-2-aminopropanoic acid