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-[9-[(6R)-4-(hydroxymethyl)-2,2-dimethyl-6,6a-dihydrofuro[3,4-d][1,3]dioxol-6-yl]-6-oxo-1H-purin-2-yl]-2-methylpropanamide by IUPAC nomenclature, provide its molecular formula.
user
C17H21N5O6
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