You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
1-(1,1-dioxo-3,4-dihydro-2H-thiochromen-4-yl)-3-[2-(2,2,2-trifluoroethoxy)phenyl]urea The above is the IUPAC name of a molecule. Write its molecular formula.
user
C18H17F3N2O4S
assistant