You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named 3-(4-ethyl-3-oxo-1,4-benzoxazin-7-yl)-1-methyl-1-[(3-methylpyridin-4-yl)methyl]urea is given. What is its corresponding molecular formula?
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C19H22N4O3
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