You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
3-[[(13S,16R,17S)-3-(aminomethyl)-17-hydroxy-13-methyl-6,7,8,9,11,12,14,15,16,17-decahydrocyclopenta[a]phenanthren-16-yl]methyl]benzamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C27H34N2O2
assistant