You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Under IUPAC nomenclature, a molecule named ethyl (8S,9S,10R,11S,13S,14S,17R)-3',11-dihydroxy-10,13-dimethyl-3,4'-dioxospiro[7,8,9,11,12,14,15,16-octahydro-6H-cyclopenta[a]phenanthrene-17,5'-furan]-2'-carboxylate is given. What is its corresponding molecular formula?
user
C25H30O7
assistant