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 N-(4-chloro-2,5-dimethoxyphenyl)-2-[[6-oxo-4-(propylsulfanylmethyl)-1H-pyrimidin-2-yl]sulfanyl]acetamide into molecular formula.
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C18H22ClN3O4S2
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