You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 2-amino-5-bromo-7-[(2R,4S,5R)-4-hydroxy-5-(hydroxymethyl)oxolan-2-yl]-3H-pyrrolo[2,3-d]pyrimidin-4-one by IUPAC nomenclature, provide its molecular formula.
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C11H13BrN4O4
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