You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Translate the chemical IUPAC name (4R)-2-amino-6-benzyl-7-methyl-4-(2-nitrophenyl)-5-oxo-4H-pyrano[3,2-c]pyridine-3-carbonitrile into its molecular formula.
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C23H18N4O4
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