You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(6R,9R)-6-(furan-2-yl)-9-phenyl-5-propanoyl-8,9,10,11-tetrahydro-6H-benzo[b][1,4]benzodiazepin-7-one is the IUPAC name of a molecule. Please give its molecular formula.
user
C26H24N2O3
assistant