[{"from": "human", "value": "Provide a description of this molecule. [C][=C][O][C][=C][Ring1][Branch1]"}, {"from": "gpt", "value": "The molecule is a clear, colorless, flammable liquid cyclic ether with an ethereal odor. Furan is used as an intermediate in the production of tetrahydrofuran, pyrrole and thiophene. Inhalation exposure to this substance causes eye and skin irritation and central nervous system depression. Furan is mutagenic in animals and is reasonably anticipated to be a human carcinogen based on evidence of carcinogenicity in experimental animals. (NCI05)"}]