You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(4aR,5S)-8-bromo-2'-(4-chlorophenyl)-5'-methyl-3-pyrimidin-2-ylspiro[2,4,4a,6-tetrahydro-1H-pyrazino[1,2-a]quinoline-5,4'-pyrazole]-3'-one The above is the IUPAC name of a molecule. Write its molecular formula.
user
C25H22BrClN6O
assistant