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What is the molecular formula of the molecule 4-[4-[(4-fluoro-2-methyl-1H-indol-5-yl)oxy]-6-methoxyquinazolin-7-yl]oxy-1-(2-oxa-6-azaspiro[3.3]heptan-6-yl)butan-1-one ?
user
C27H27FN4O5
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