You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule N-tert-butyl-2-[[4-(3-chloro-4-methoxyphenyl)-5-phenyl-1,2,4-triazol-3-yl]sulfanyl]acetamide into molecular formula.
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C21H23ClN4O2S
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