You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-(3,4-dimethoxyphenyl)-2-[[4-(ethylsulfanylmethyl)-6-oxo-1H-pyrimidin-2-yl]sulfanyl]propanamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C18H23N3O4S2
assistant