You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
6-amino-4-[2-(2,4-dimethoxyphenyl)-2-oxoethyl]-2-propan-2-ylpyrido[3,2-b][1,4]oxazin-3-one The above is the IUPAC name of a molecule. Write its molecular formula.
user
C20H23N3O5
assistant