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 2-phenyl-1-[(3R)-3-[4-[5-(trifluoromethyl)-1,2,4-oxadiazol-3-yl]phenyl]sulfanylpyrrolidin-1-yl]ethanone into molecular formula.
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C21H18F3N3O2S
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