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What is the molecular formula of the compound with this IUPAC name (7-but-2-ynyl-3-cyclopentyl-1-methyl-2,6-dioxo-8-piperazin-1-yl-8H-purin-9-yl) 2,2,2-trifluoroacetate ?
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C21H27F3N6O4
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