You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named N-[(3R)-1,1-dioxothiolan-3-yl]-3-[7-(3-fluorophenyl)-5,6-dimethyl-4-oxopyrrolo[2,3-d]pyrimidin-3-yl]propanamide by IUPAC nomenclature, provide its molecular formula.
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C21H23FN4O4S
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