You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Name the molecular formula for the molecule established as 7-methyl-4-oxo-N-[(1-phenylpyrazol-4-yl)methyl]pyrido[1,2-a]pyrimidine-3-carboxamide using the IUPAC nomenclature.
user
C20H17N5O2
assistant