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,5S,8R,9S)-4,5,9,11,14-pentamethyl-6-methylidene-15-oxapentacyclo[9.3.2.15,8.01,10.02,8]heptadec-12-en-16-one .
user
C22H30O2
assistant