You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named N,N-diethyl-2-[4-methyl-4-(2-methylpropyl)-2,5-dioxoimidazolidin-1-yl]acetamide by IUPAC nomenclature, provide its molecular formula.
user
C14H25N3O3
assistant