You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-[2-[(2S,6S)-2,6-dimethylmorpholin-4-yl]-2-methylpropyl]-4-oxochromene-2-carboxamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C20H26N2O4
assistant