You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-[(3S,8R,9S,10R,13S,14S,16R,17S)-3-hydroxy-10,13,16-trimethyl-2,3,4,7,8,9,11,12,14,15,16,17-dodecahydro-1H-cyclopenta[a]phenanthren-17-yl]acetamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C22H35NO2
assistant