You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Can you give the molecular formula of the molecule 7-(4-tert-butylpiperazin-1-yl)-1-methyl-2-phenyl-4,5,6,7-tetrahydroimidazo[4,5-c]pyridine ?
user
C21H31N5
assistant