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 N-[2-methyl-1-(3-methyl-1,2,4-oxadiazol-5-yl)propyl]-2-(1-phenylpyrazol-4-yl)acetamide into its molecular formula.
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C18H21N5O2
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