You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name N-[[4-[5-(methylamino)-6-prop-1-en-2-yl-3H-azepin-7-yl]phenyl]methyl]methanesulfonamide into its molecular formula.
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C18H23N3O2S
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