You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named (2R,5R)-2-(6-amino-2-ethynylpurin-9-yl)-5-(hydroxymethyl)oxolane-3,4-diol is given. What is its corresponding molecular formula?
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C12H13N5O4
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