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 (1R,7R)-N-[(3-methoxyphenyl)methyl]-3-(5-methyl-1,2-oxazol-3-yl)-4-oxo-10-oxa-3-azatricyclo[5.2.1.01,5]dec-8-ene-6-carboxamide into molecular formula.
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C21H21N3O5
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