You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule (2R,3S,4R,5R)-2-(hydroxymethyl)-5-[6-[(3-iodophenyl)methylamino]purin-9-yl]-3-methyloxolane-3,4-diol into molecular formula.
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C18H20IN5O4
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