[{"from": "human", "value": "Could you provide a description of this molecule? [C][=C][C][=Branch1][S][=C][C][=C][Ring1][=Branch1][C][C@@H1][Branch1][=Branch1][C][=Branch1][C][=O][O-1][NH3+1][N]"}, {"from": "gpt", "value": "The molecule is an amino acid zwitterion arising from transfer of a proton from the carboxy to the amino group of 4-amino-L-phenylalanine; major species at pH 7.3. It is a tautomer of a 4-amino-L-phenylalanine."}]