You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named (2S)-7-[(Z)-heptadec-8-enyl]-2-(hydroxymethyl)-6-[(Z)-15-methylhexadec-7-enyl]-2,3-dihydro-1,4-dioxepin-5-one by IUPAC nomenclature, provide its molecular formula.
user
C40H72O4
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