You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
14-phenyl-16-oxa-14-azatetracyclo[8.6.0.02,7.011,15]hexadeca-1(10),2,4,6,8-pentaen-13-one The above is the IUPAC name of a molecule. Write its molecular formula.
user
C20H15NO2
assistant