You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Provide the molecular formula for the IUPAC named substance (1R,2R,6R,7R,8R,12S)-5-(2-chlorophenyl)-10-[2-(dimethylamino)ethyl]-3-oxa-4,10-diazatetracyclo[5.5.1.02,6.08,12]tridec-4-ene-9,11-dione .
user
C20H22ClN3O3
assistant