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 [(2S)-1-[4-[3-(2-chlorophenyl)-1,2,4-oxadiazol-5-yl]piperidin-1-yl]-1-oxopropan-2-yl] acetate into molecular formula.
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C18H20ClN3O4
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