[{"from": "human", "value": "Synthesize a molecule that matches the given characteristics. The molecule is an acetylenic compound that is acetylene in which the hydrogens are replaced by carboxy groups. It is a C4-dicarboxylic acid and an acetylenic compound. It is a conjugate acid of an acetylenedicarboxylate(1-)."}, {"from": "gpt", "value": "[C][#Branch1][#Branch1][#C][C][=Branch1][C][=O][O][C][=Branch1][C][=O][O]"}]