You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule pyridin-4-yl-[3-[6-[3-(trifluoromethyl)phenyl]pyrazin-2-yl]piperidin-1-yl]methanone into molecular formula.
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C22H19F3N4O
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