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What is the molecular formula of the compound with this IUPAC name N-[3-[7-hydroxy-2-(pyridine-3-carbonyl)spiro[1,3,6,7,8,8a-hexahydropyrrolo[1,2-a]pyrazine-4,3'-azetidine]-1'-yl]-3-oxopropyl]acetamide ?
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C20H27N5O4
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