[{"from": "human", "value": "Synthesize a molecule that matches the given characteristics. The molecule is a sulfur-containing amino-acid anion that is the conjugate base of methionine, arising from deprotonation of the carboxy group. It is an alpha-amino-acid anion and a sulfur-containing amino-acid anion. It is a conjugate base of a methionine."}, {"from": "gpt", "value": "[C][S][C][C][C][Branch1][=Branch1][C][=Branch1][C][=O][O-1][N]"}]