[{"from": "human", "value": "Could you give me a brief overview of this molecule? [C][Branch1][#Branch1][C][C][=Branch1][C][=O][O][C][=Branch1][C][=O][C][N]"}, {"from": "gpt", "value": "The molecule is a topically administered metabolic precursor of protoporphyrin IX. After topical administration, aminolevulinic acid (ALA) is converted to protoporphyrin IX (PpIX) which is a photosensitizer. When the proper wavelength of light activates protoporphyrin IX, singlet oxygen is produced, resulting in a local cytotoxic effect. (NCI04)"}]