You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 3-[(3R)-3-(4-chlorophenyl)-3-[(4-methoxyphenyl)methylsulfanyl]propanoyl]-1,3-oxazolidin-2-one into its molecular formula.
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C20H20ClNO4S
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