You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-(2,4-difluorophenyl)-2-(1,3-dimethyl-2,4-dioxo-7-propylpyrimido[4,5-d]pyrimidin-5-yl)sulfanylacetamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C19H19F2N5O3S
assistant