You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named N-[5-bromo-2-hydroxy-1-(piperidin-1-ylmethyl)indol-3-yl]imino-1-ethyl-7-methyl-4-oxo-1,8-naphthyridine-3-carboxamide by IUPAC nomenclature, provide its molecular formula.
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C26H27BrN6O3
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