You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(2R,4R)-9-(2,4-difluorophenyl)-N-[2-(6-oxo-1H-pyridin-3-yl)propan-2-yl]-8,9-diazatricyclo[4.3.0.02,4]nona-1(6),7-diene-7-carboxamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C22H20F2N4O2
assistant