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 (3-fluorophenyl)-[4-[[3-(2-methylpropyl)-1,2,4-oxadiazol-5-yl]methyl]piperazin-1-yl]methanone into molecular formula.
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C18H23FN4O2
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