You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(1S,8S,15R,19S)-4-[(2R)-butan-2-yl]-17-(2-ethoxyphenyl)-17-azapentacyclo[6.6.5.02,7.09,14.015,19]nonadeca-2(7),3,5,9,11,13-hexaene-16,18-dione is the IUPAC name of a molecule. Please give its molecular formula.
user
C30H29NO3
assistant