[{"from": "human", "value": "Based on the given information, design a molecule that meets the desired specifications. The molecule is an amino acid zwitterion obtained by transfer of a proton from the carboxy to the amino group of tetrahydrotyrosine; major species at pH 7.3. It is a tautomer of a tetrahydrotyrosine."}, {"from": "gpt", "value": "[C][C][C][Branch1][S][C][=C][C][Ring1][=Branch1][C][C][Branch1][=Branch1][C][=Branch1][C][=O][O-1][NH3+1][O]"}]