You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
11-methyl-8,14-bis(2,3,4,5,6-pentamethylphenyl)-5,17-dipyridin-4-yl-1-aza-8,14-diborapentacyclo[11.7.1.02,7.09,21.015,20]henicosa-2(7),3,5,9,11,13(21),15(20),16,18-nonaene is the IUPAC name of a molecule. Please give its molecular formula.
user
C51H49B2N3
assistant