You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 2-[[4-(4-chlorophenyl)-5-cyano-6-oxo-1H-pyrimidin-2-yl]sulfanyl]-N-(2-methylphenyl)acetamide into molecular formula.
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C20H15ClN4O2S
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