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 2-[(4,6-dimethyl-2-oxo-1H-pyridin-3-yl)methyl]-7-methoxy-1-oxo-3,4-dihydroisoquinoline-6-carbonitrile into molecular formula.
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C19H19N3O3
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