You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-[[(4R)-4-[(3S,5S,8R,9S,10S,12R,13S,14S,17S)-3,8,12-trihydroxy-10,13-dimethyl-1,2,3,4,5,6,7,9,11,12,14,15,16,17-tetradecahydrocyclopenta[a]phenanthren-17-yl]pentanoyl]amino]ethanesulfonic acid is the IUPAC name of a molecule. Please give its molecular formula.
user
C26H45NO7S
assistant