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For the molecule named 3-[4-[2-[2-[2-[2-[4-[6-[(6-acetyl-8-cyclopentyl-5-methyl-7-oxopyrido[2,3-d]pyrimidin-2-yl)amino]pyridin-3-yl]piperazin-1-yl]ethoxy]ethoxy]ethoxy]ethoxy]-2-methyl-6-oxopyridin-1-yl]piperidine-2,6-dione by IUPAC nomenclature, provide its molecular formula.
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C43H55N9O9
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