You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule 7-(3-ethoxypropyl)-6-imino-N-methyl-2-oxo-1,7,9-triazatricyclo[8.4.0.03,8]tetradeca-3(8),4,9,11,13-pentaene-5-carboxamide into molecular formula.
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C18H21N5O3
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