You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
4-[2-[(2R)-4-(3-pyridin-3-ylpropanoyl)morpholin-2-yl]ethyl]-1H-pyrimidin-6-one The above is the IUPAC name of a molecule. Write its molecular formula.
user
C18H22N4O3
assistant