You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-[[17-(6-hydroxy-6-methylheptan-2-yl)-10,13-dimethyl-2,3,4,7,8,9,11,12,14,15,16,17-dodecahydro-1H-cyclopenta[a]phenanthren-3-yl]oxycarbonyloxy]ethyl-trimethylazanium is the IUPAC name of a molecule. Please give its molecular formula.
user
C33H58NO4+
assistant