You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
methyl (7R,17R)-10,13-dimethyl-3,5'-dioxospiro[2,6,7,8,12,14,15,16-octahydro-1H-cyclopenta[a]phenanthrene-17,2'-oxolane]-7-carboxylate;methyl (1R,9R,14R)-2,15-dimethyl-5,5'-dioxospiro[18-oxapentacyclo[8.8.0.01,17.02,7.011,15]octadec-6-ene-14,2'-oxolane]-9-carboxylate is the IUPAC name of a molecule. Please give its molecular formula.
user
C48H60O11
assistant