You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Please write the molecular formula of the molecule [3-(cyclobutadienyl)-1,2,4,5-tetrahydro-[1,4]diazepino[1,7-a]benzimidazol-8-yl]-morpholin-4-ylmethanone .
user
C20H22N4O2
assistant