[{"from": "human", "value": "Provide a brief overview of this molecule. [C][Branch1][=N][C][S][C][C@@H1][Branch1][=Branch1][C][=Branch1][C][=O][O-1][NH3+1][C@@H1][Branch1][=Branch1][C][=Branch1][C][=O][O-1][NH3+1]"}, {"from": "gpt", "value": "The molecule is dizwitterionic form of L-cystathionine arising from transfer of two protons from the carboxy to the amino groups; major species at pH 7.3. It is a tautomer of a L-cystathionine."}]