You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named (2R)-1-[2-(4-bromophenoxy)ethoxy]-3-[4-(2-fluorophenyl)piperazin-1-ium-1-yl]propan-2-ol is given. What is its corresponding molecular formula?
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C21H27BrFN2O3+
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