You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Translate the chemical IUPAC name 6-(3-fluorophenyl)-3-methyl-7-[1-(7H-purin-6-ylamino)ethyl]-[1,3]thiazolo[3,2-a]pyrimidin-5-one;methanesulfonic acid into its molecular formula.
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C21H20FN7O4S2
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