You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule N-[4-[2-[(4-fluorophenyl)methylamino]ethyl]-2-methoxyphenyl]-2-(5-methylpyrazin-2-yl)acetamide into molecular formula.
user
C23H25FN4O2
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