You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named [(3R,6R,7R,10S,13R,17R)-6-ethyl-7-formyloxy-10,13-dimethyl-17-[(2R)-4-phosphonooxybutan-2-yl]-2,3,4,5,6,7,8,9,11,12,14,15,16,17-tetradecahydro-1H-cyclopenta[a]phenanthren-3-yl] formate by IUPAC nomenclature, provide its molecular formula.
user
C27H45O8P
assistant