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 3-[(3aR,10bR)-3a,10b-dimethyl-3-[(1S)-1-(5-methyl-6-oxo-2,3-dihydropyran-2-yl)ethyl]-8-propan-2-ylidene-2,3,4,5-tetrahydro-1H-cyclohepta[e]inden-7-yl]propanoic acid .
user
C30H40O4
assistant