[{"from": "human", "value": "Provide a brief overview of this molecule. [C][=Branch1][C][=O][=O].[O][=O]"}, {"from": "gpt", "value": "The molecule is an inhalant consisting of hyperoxic gas (95%-98% oxygen and 2%-5% carbon dioxide) with radiosensitizing properties.  Inhaled carbogen reduces diffusion-limited tumor hypoxia, increasing tumor radiosensitivity due to the increased availability of molecular oxygen for cytotoxic radiation-induced oxygen free radical production. (NCI04)"}]