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 N-[3-[4-(difluoromethoxy)phenyl]oxan-3-yl]-5-(5-oxo-4H-1,2,4-oxadiazol-3-yl)pyrazine-2-carboxamide into molecular formula.
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C19H17F2N5O5
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