You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 6-N-[1-(5-fluoropyridin-2-yl)ethyl]-2-N-(2-methoxypyridin-3-yl)pyridine-2,6-diamine into molecular formula.
user
C18H18FN5O
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