You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
dimethyl 3-[2-(4-methyl-2,5-dioxoimidazolidin-1-yl)phenyl]-2,6-dihydro-1,3-oxazine-4,5-dicarboxylate is the IUPAC name of a molecule. Please give its molecular formula.
user
C18H19N3O7
assistant