You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 3,6-dimethyl-2-[(4-methylphenyl)methylsulfanyl]-5-[3-(trifluoromethyl)phenoxy]pyrimidin-4-one into molecular formula.
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C21H19F3N2O2S
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