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 7-[[3-[(4-ethylpiperazin-1-yl)methyl]phenoxy]methyl]-2,3,4,6,7,8,9,9a-octahydro-1H-pyrido[1,2-a]pyrazine .
user
C22H36N4O
assistant