You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named ethyl 2-[[3-[2-[(9-hydroxy-5b,8,8,11a-tetramethyl-2,3,4,5,5a,6,7,7a,9,10,11,11b,12,13,13a,13b-hexadecahydro-1H-cyclopenta[a]chrysene-3a-carbonyl)amino]ethyl]benzoyl]amino]acetate by IUPAC nomenclature, provide its molecular formula.
user
C39H58N2O5
assistant