You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 4-(3-chloro-4-methylanilino)-6-(3,4-dimethoxyphenyl)-2-methylsulfanylpyrimidine-5-carbonitrile by IUPAC nomenclature, provide its molecular formula.
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C21H19ClN4O2S
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