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What is the molecular formula of the molecule 9-[(1R,6S,8R,9R,10R,15R,17R,18R)-8-(6-aminopurin-9-yl)-9,18-difluoro-3-oxido-12,12-dioxo-3-sulfanylidene-2,4,7,13,16-pentaoxa-12lambda6-thia-11-aza-3lambda5-phosphatricyclo[13.3.0.06,10]octadecan-17-yl]-1H-purin-6-one ?
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C20H20F2N10O9PS2-
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