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-[(1R)-1-[5-[2-(4-bromo-2-methylanilino)-2-oxoethyl]sulfanyl-4-methyl-1,2,4-triazol-3-yl]ethyl]-4-chlorobenzamide by IUPAC nomenclature, provide its molecular formula.
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C21H21BrClN5O2S
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