[{"from": "human", "value": "Please give me some details about this molecule. [C][C][Branch1][C][C][C][C@@H1][Branch1][S][C][=Branch1][C][=O][N][C][C][C][C][NH1+1][=C][Branch1][C][N][N][N][C][=Branch1][C][=O][C@@H1][C@H1][Branch1][Ring2][O][Ring1][Ring1][C][=Branch1][C][=O][O-1]"}, {"from": "gpt", "value": "The molecule is zwitterionic form of E64, a compound isolated from Aspergillus japonicus, resulting from transfer of a proton from the carboxy to the guanidino group; major species at pH 7.3. It is a tautomer of an E64."}]