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 (4-bromophenyl)-[4-[(5-methyl-1H-pyrazol-4-yl)methyl]piperazin-1-yl]methanone is given. What is its corresponding molecular formula?
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C16H19BrN4O
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