You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 1-[(3,4-dimethoxyphenyl)methyl]-N-(5-methyl-1,2-oxazol-3-yl)-5-oxopyrrolidine-3-carboxamide into molecular formula.
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C18H21N3O5
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