You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named (1S,4R,5S,6S,8S)-8-(hydroxymethyl)-2-azabicyclo[2.2.2]octane-4,5,6-triol by IUPAC nomenclature, provide its molecular formula.
user
C8H15NO4
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