You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(5S,7'S)-18'-cyclopropyl-7'-methylspiro[furan-5,6'-pentacyclo[8.8.0.02,7.03,5.011,16]octadec-11(16)-ene]-2,14'-dione The above is the IUPAC name of a molecule. Write its molecular formula.
user
C25H30O3
assistant