You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
4-(difluoromethoxy)-3-methoxy-N-[4-(2,4,5-trimethylphenyl)-1,3-thiazol-2-yl]benzamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C21H20F2N2O3S
assistant