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 N-[(3aS,10aS)-2,6-diamino-4-[(diacetylamino)methyl]-10,10-dihydroxy-3a,4,8,9-tetrahydro-1H-pyrrolo[1,2-c]purin-9-yl]-3-methylbenzamide into molecular formula.
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C21H28N8O5
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