You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Please write the molecular formula of the molecule (8S,9S,10R,13S,14S,17S)-17-(1-aminoethyl)-10,13-dimethyl-7,8,9,12,14,15,16,17-octahydro-6H-cyclopenta[a]phenanthrene-3,11-dione .
user
C21H29NO2
assistant