[{"from": "human", "value": "Synthesize a molecule that matches the given characteristics. The molecule is a dicarboxylic acid dianion resulting from the deprotonation of both of the carboxy groups of 4,4'-disulfanyldibutanoic acid. It is a conjugate base of a 4,4'-disulfanyldibutanoic acid."}, {"from": "gpt", "value": "[C][Branch1][#Branch1][C][C][=Branch1][C][=O][O-1][C][S][S][C][C][C][C][=Branch1][C][=O][O-1]"}]