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 1-methyl-3-[[6-[(2-methylpropan-2-yl)oxy]pyridin-3-yl]methyl]-1-[(1S)-1-pyridin-4-ylpropyl]urea .
user
C20H28N4O2
assistant