You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name (2R)-2-[[5-(4-chlorophenyl)-1,3-oxazol-2-yl]methylsulfanyl]-N-[(3S)-1,1-dioxothiolan-3-yl]-N-prop-2-ynylpropanamide into its molecular formula.
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C20H21ClN2O4S2
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