You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(2,8-dimethylquinolin-3-yl)-[4-(1H-1,2,4-triazol-5-yl)piperazin-1-yl]methanone is the IUPAC name of a molecule. Please give its molecular formula.
user
C18H20N6O
assistant