You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 2-[(2,4-dimethoxyphenyl)methyl]-1-ethyl-3-[4-(2-oxopyridin-1-yl)butyl]guanidine by IUPAC nomenclature, provide its molecular formula.
user
C21H30N4O3
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