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-[3-chloro-5-(trifluoromethyl)pyridin-2-yl]-2-[[5-oxo-4-(2-phenylethyl)-1H-1,2,4-triazol-3-yl]sulfanyl]acetamide by IUPAC nomenclature, provide its molecular formula.
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C18H15ClF3N5O2S
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