[{"from": "human", "value": "Describe this molecule. [C][S+1][Branch1][C][C][C][C][C@@H1][Branch1][=Branch1][C][=Branch1][C][=O][O-1][NH3+1]"}, {"from": "gpt", "value": "The molecule is a sulfonium compound that is a tautomer of S-methyl-L-methionine, arising from transfer of a proton from the carboxy to the amino group; major species at pH 7.3. It is a tautomer of a S-methyl-L-methionine."}]