You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule 10,11-dimethoxy-N-[(5-methylfuran-2-yl)methyl]-8-oxo-5,6,13,13a-tetrahydroisoquinolino[2,1-b]isoquinoline-13-carboxamide into molecular formula.
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C26H26N2O5
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