You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
6,11-dihydropyrrolo[2,1-c][1,4]benzodiazepin-5-yl-[3-methyl-4-(6-methylcyclohexen-1-yl)phenyl]methanone The above is the IUPAC name of a molecule. Write its molecular formula.
user
C27H28N2O
assistant