You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-[[17-[N-(dimethylamino)-C-methylcarbonimidoyl]-10,13-dimethyl-1,2,6,7,8,9,11,12,14,15,16,17-dodecahydrocyclopenta[a]phenanthren-3-ylidene]amino]-N-methylmethanamine is the IUPAC name of a molecule. Please give its molecular formula.
user
C25H42N4
assistant