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What is the molecular formula of the compound with this IUPAC name 2-[[4-[2-(2-amino-4-oxo-3,7-dihydropyrrolo[2,3-d]pyrimidin-5-yl)ethyl]benzoyl]amino]-4-(2H-tetrazol-5-yl)butanoic acid ?
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C20H21N9O4
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