You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 3-[2-(4-chlorophenyl)sulfonylethyl]-N-[(2S)-2-phenylpropyl]-1,2,4-oxadiazole-5-carboxamide into its molecular formula.
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C20H20ClN3O4S
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