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 2-(2-oxoazetidin-1-yl)-2-phenyl-N-(7H-pyrrolo[3,4-d]pyrimidin-7-ylmethyl)acetamide into molecular formula.
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C18H17N5O2
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