You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 1-[4-[4-[[4-(4-bromophenyl)pyrimidin-2-yl]amino]benzoyl]piperazin-1-yl]ethanone by IUPAC nomenclature, provide its molecular formula.
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C23H22BrN5O2
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