You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
What is the molecular formula of the molecule identified by (5R,9R,10R,13R,14S,17R)-17-[(2R,5R)-5,6-dimethylhept-3-en-2-yl]-3,5,14-trihydroxy-10,13-dimethyl-1,2,3,4,9,11,12,15,16,17-decahydrocyclopenta[a]phenanthren-6-one ?
user
C28H44O4
assistant