You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Can you give the molecular formula of the molecule (15R,19R)-17-[4-(4-chlorophenyl)phenyl]-17-azapentacyclo[6.6.5.02,7.09,14.015,19]nonadeca-2,4,6,9,11,13-hexaene-16,18-dione ?
user
C30H20ClNO2
assistant