You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named N-[(4-bromo-2-ethylpyrazol-3-yl)methyl]-1-(4-nitrophenyl)sulfonylpiperidine-4-carboxamide by IUPAC nomenclature, provide its molecular formula.
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C18H22BrN5O5S
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