You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(E)-N-[(4S)-7-methoxy-2,2-dimethyl-3,4-dihydrochromen-4-yl]-3-(3-nitrophenyl)prop-2-enamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C21H22N2O5
assistant