You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 3-[[4-(6-methoxy-3,4-dihydropyridin-4-yl)phenyl]methyl]pyrido[3,2-d]pyrimidin-4-one into molecular formula.
user
C20H18N4O2
assistant