You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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N-[4-chloro-2-[(2-methyl-7-oxo-[1,2]oxazolo[2,3-a]pyrimidin-5-yl)methoxy]phenyl]cyclopropanecarboxamide is the IUPAC name of a molecule. Please give its molecular formula.
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C18H16ClN3O4
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