You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Translate the chemical IUPAC name 2-[[5-(4-chlorophenyl)-1,3-oxazol-2-yl]methylsulfanyl]-N-(pyrrolidin-2-ylmethyl)propanamide into its molecular formula.
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C18H22ClN3O2S
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