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What is the molecular formula of the compound with this IUPAC name ethyl 6-imino-13-methyl-2-oxo-7-propan-2-yl-1,7,9-triazatricyclo[8.4.0.03,8]tetradeca-3(8),4,9,11,13-pentaene-5-carboxylate ?
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C18H20N4O3
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