[{"from": "human", "value": "Could you provide a description of this molecule? [C][C][C][Branch1][S][C][=C][C][Ring1][=Branch1][C][C][Branch1][=Branch1][C][=Branch1][C][=O][O-1][NH3+1][O]"}, {"from": "gpt", "value": "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."}]