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 potassium;(8R,9S,13S,14S)-3-methoxy-13-methyl-6,7,8,9,11,12,14,15-octahydrocyclopenta[a]phenanthren-17-olate .
user
C19H23KO2
assistant