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What is the molecular formula of the molecule 2-amino-9-[(8R,15R,17R)-17-(6-aminopurin-9-yl)-9-fluoro-3,12,18-trihydroxy-3,12-dioxo-2,4,7,11,13-pentaoxa-3lambda5,12lambda5-diphosphatricyclo[13.3.0.06,10]octadec-6(10)-en-8-yl]-1H-purin-6-one ?
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C21H23FN10O11P2
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