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 2,5-dichloro-N-methyl-N-[(3-propyl-3a,7a-dihydroimidazo[4,5-b]pyridin-2-yl)methyl]benzamide .
user
C18H20Cl2N4O
assistant