You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 1-[9-(hydroxymethyl)-1-(methoxymethoxymethyl)-5-methyl-3-azabicyclo[3.3.1]nonan-3-yl]ethanone by IUPAC nomenclature, provide its molecular formula.
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C15H27NO4
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