[{"from": "human", "value": "Based on the given information, design a molecule that meets the desired specifications. The molecule is an amino acid zwitterion arising from transfer of a proton from the carboxy to the amino group of O-acetyl-L-serine; major species at pH 7.3. It is a tautomer of an O-acetyl-L-serine."}, {"from": "gpt", "value": "[C][C][=Branch1][C][=O][O][C][C@@H1][Branch1][=Branch1][C][=Branch1][C][=O][O-1][NH3+1]"}]