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 6-(4-methyl-3-oxo-4a,5,7,7a-tetrahydropyrrolo[3,4-b][1,4]oxazin-6-yl)pyridine-3-carbonitrile into molecular formula.
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C13H14N4O2
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