You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 9-[[1-bromo-2,2-difluoro-3-(phenylmethoxymethyl)cyclopropyl]methyl]-6-chloropurin-2-amine by IUPAC nomenclature, provide its molecular formula.
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C17H15BrClF2N5O
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