You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
3-(5-tert-butyl-1,2-oxazol-3-yl)-1-[(4-ethyl-5-propyl-1,3-dioxolan-2-yl)methyl]-1-methylurea is the IUPAC name of a molecule. Please give its molecular formula.
user
C18H31N3O4
assistant