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'R,6bS,7'aR)-3-hydroxy-3',6',10,11b-tetramethylspiro[1,2,3,4,6,6a,6b,7,8,11a-decahydrobenzo[a]fluorene-9,2'-3a,4,5,6,7,7a-hexahydro-3H-furo[3,2-b]pyridine]-11-one .
user
C27H39NO3
assistant