You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Provide the molecular formula for the IUPAC named substance (7a-phenyl-2-pyrimidin-2-yl-1,3,3a,4,6,7-hexahydropyrrolo[3,4-c]pyridin-5-yl)-(1,2-oxazol-5-yl)methanone .
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C21H21N5O2
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