You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
6-[(4-methoxyphenyl)methyl]-N,4-dimethyl-5-methylidene-3-oxo-7,8-dihydro-2H-2,6-naphthyridine-1-carboxamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C20H23N3O3
assistant