You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named (2-ethylpiperidin-1-yl)-[2-[4-(4-fluorophenyl)piperazin-1-yl]pyrimidin-5-yl]methanone by IUPAC nomenclature, provide its molecular formula.
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C22H28FN5O
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