You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
3-(4,6-dimethyl-2-methylsulfanylpyrimidin-5-yl)-N-[4-(4-methyl-3-nitrophenyl)-1,3-thiazol-2-yl]propanamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C20H21N5O3S2
assistant