[{"from": "human", "value": "Provide a description of this molecule. [C][C][=C][C][=Branch1][C][=O][O][C][Ring1][=Branch1][C][C][=Branch1][C][=O][O]"}, {"from": "gpt", "value": "The molecule is a 5-oxo-2-furylacetic acid having a 3-methyl substituent. It is a conjugate acid of a 4-carboxylatomethyl-3-methylbut-2-en-1,4-olide(1-)."}]