You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Provide the molecular formula for the IUPAC named substance 2-[2-[[4-[6-(1H-imidazol-2-yl)pyrazin-2-yl]piperidin-1-yl]methyl]phenoxy]acetic acid .
user
C21H23N5O3
assistant