You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(1S,3S,6S,7R,9S)-N-[4-(morpholine-4-carbonyl)phenyl]-5-oxo-4-oxatricyclo[4.2.1.03,7]nonane-9-carboxamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C20H22N2O5
assistant