You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
4-[(3-chlorophenyl)methyl]-3,5-dioxo-N-(oxolan-2-ylmethyl)-2-phenyl-1,2,4-triazine-6-carboxamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C22H21ClN4O4
assistant