You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule (2R)-N-[[3-ethyl-1-(4-fluorophenyl)-5-(4-methylpiperazin-1-yl)pyrazol-4-yl]methyl]-N-[(4-fluorophenyl)methyl]butan-2-amine into molecular formula.
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C28H37F2N5
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