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What is the molecular formula of the compound with this IUPAC name 1'-(5-bromopyridine-2-carbonyl)-5-(3,5-difluorophenyl)spiro[5,6,7,7a-tetrahydropyrrolo[2,1-b][1,3]oxazole-2,4'-piperidine]-3-one ?
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C22H20BrF2N3O3
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