You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Under IUPAC nomenclature, a molecule named 3,4,5,7-tetrazapentacyclo[9.7.1.12,6.015,19.010,20]icosa-1(18),2,4,6,8,10(20),11,13,15(19),16-decaene is given. What is its corresponding molecular formula?
user
C16H8N4
assistant