You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
3,5-dimethyl-N-[1-methyl-2-oxo-5-(piperidine-1-carbonyl)pyridin-3-yl]-1,2-oxazole-4-carboxamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C18H22N4O4
assistant